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Journal articles on the topic 'Root density; soil moisture'
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1
Konôpka, B., L. Pagès, and C. Doussan. "Soil compaction modifies morphological characteristics of seminal maize roots." Plant, Soil and Environment 55, No. 1 (2009): 1–10. http://dx.doi.org/10.17221/380-pse.
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An evaluation of the effects of soil structural heterogeneity on maize (<I>Zea mays</I> L.) root system architecture was carried out on plants grown in boxes containing fine soil and clods. The clods were prepared at two levels of moisture (0.17 and 0.20 g/g) and bulk density (ranges 1.45–1.61 g/ml and 1.63–1.79 g/ml). Soil moisture directly affected the probability of clod penetration by maize roots. Primary roots inside the clods manifested morphological deformations in the form of bends. We observed a significant increase of bends per root length at lower soil moisture (<I>P</I> = 0.02). Root diameter and branching density increased, and lateral root length decreased considerably inside the clods. However, once emerging out of the clods and into free soil, values of all three characteristics remained low. While changes in root diameter were caused mainly by clod moisture (<I>P</I> < 0.05), length of lateral roots was related to bulk density (<I>P</I> < 0.01). Branching density was modified exclusively by an interactive effect of both factors (<I>P</I> < 0.05).
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Reardon, James, Roger Hungerford, and Kevin Ryan. "Factors affecting sustained smouldering in organic soils from pocosin and pond pine woodland wetlands." International Journal of Wildland Fire 16, no. 1 (2007): 107. http://dx.doi.org/10.1071/wf06005.
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The smouldering combustion of peat and muck soil plays an important role in the creation and maintenance of wetland communities. This experimental study was conducted to improve our understanding of how moisture and mineral content constrain smouldering in organic soil. Laboratory burning was conducted with root mat and muck soil samples from pocosin and pond pine woodland wetlands common on the North Carolina coastal plain. The results of laboratory and prescribed burning were compared. Laboratory results showed that moisture and mineral content influenced sustained smouldering in root mat soils. Predictions based on logistic regression analysis show that root mat soils with an average mineral content of 4.5% had an estimated 50% probability of sustained smouldering at a moisture content of 93%, whereas at moisture contents above 145% the estimated probability was less than 10%. The odds that root mat soil will sustain smouldering decrease by 19.3% for each 5% increase in moisture content. Root mat soils with an average mineral content of 5.5% and a moisture content of 93% had an estimated 61% probability of sustained smouldering. The odds that root mat soil will sustain smouldering combustion increased by 155.9% with each 1% increase in mineral content. Root mat and muck soils differ in physical and chemical characteristics expected to influence smouldering behaviour. The formation of muck soil has led to increases in density, smaller soil particle size, changes in water holding characteristics and increases in waxes, resins and bituminous compounds. Muck soil smouldered at higher moisture contents than root mat soil. Muck soil at a moisture content of 201% had an estimated 50% probability of sustained smouldering, whereas at moisture contents above 260% the estimated probability was less than 10%. The odds that muck soil will sustain smouldering combustion decrease by 17.2% with each 5% increase in moisture content. Ground fire in the prescribed burns stopped its vertical spread in organic soils at moisture contents consistent with logistic regression predictions developed from our laboratory results.
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Zarehaghi, D., M. R. Neyshabouri, M. Gorji, R. Hassanpour, and A. Bandehagh. "Growth and development of pistachio seedling root at different levels of soil moisture and compaction in greenhouse conditions." Soil and Water Research 12, No. 1 (2017): 60–66. http://dx.doi.org/10.17221/146/2015-swr.
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Soil moisture and compaction are important factors for growth and development of plant root. This study was conducted as a nested design with two factors and three replications to investigate the behaviour of pistachio seedling roots at different levels of soil compaction and moisture in a sandy loam soil under greenhouse conditions. The first factor was soil compaction at four levels of bulk density (1.35, 1.5, 1.65, and 1.8 g/cm<sup>3</sup>). The second factor was soil moisture with six levels ranging 0.07–0.49 cm<sup>3</sup>/cm<sup>3</sup>. Moisture monitoring at each treatment was carried out by a time domain reflectometer device every two days. At the end of experiment, root and shoot dry weight, shoot to root weight ratio, root length, and rooting depth were measured. Results showed that soil compaction and moisture content effects on all measured characteristics were significant (P &lt; 0.01). At the bulk density of 1.35 and 1.5 g/cm<sup>3</sup> and moisture ranges of 0.14–0.49 cm<sup>3</sup>/cm<sup>3</sup> (levels 1–4) the values obtained for all the measured characteristics were the highest. At the bulk density of 1.65 g/cm<sup>3</sup> the optimum moisture range was 0.22–0.33 cm<sup>3</sup>/cm<sup>3</sup>; at the bulk density of 1.8 g/cm<sup>3</sup> the moisture range optimum for root growth and development was 0.23–0.27 cm<sup>3</sup>/cm<sup>3</sup>. A drop in soil moisture from 0.49 to 0.07 cm<sup>3</sup>/cm<sup>3</sup> and concomitant increase in soil bulk density from 1.35 to 1.80 g/cm<sup>3</sup> led to a severe decline in root dry weight, shoot dry weight, shoot to root dry weight ratio, root length, and rooting depth by as much as 65, 92, 69, 73 and 66%, respectively.
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Maan, Cynthia, Marie-Claire ten Veldhuis, and Bas J. H. van de Wiel. "Dynamic root growth in response to depth-varying soil moisture availability: a rhizobox study." Hydrology and Earth System Sciences 27, no. 12 (2023): 2341–55. http://dx.doi.org/10.5194/hess-27-2341-2023.
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Abstract. Plant roots are highly adaptable, but their adaptability is not included in crop and land surface models. They rely on a simplified representation of root growth, which is independent of soil moisture availability. Data of subsurface processes and interactions, needed for model setup and validation, are scarce. Here we investigated soil-moisture-driven root growth. To this end, we installed subsurface drip lines and small soil moisture sensors (0.2 L measurement volume) inside rhizoboxes (length × width × height of 45 × 7.5 × 45 cm). The development of the vertical soil moisture and root growth profiles is tracked with a high spatial and temporal resolution. The results confirm that root growth is predominantly driven by vertical soil moisture distribution, while influencing soil moisture at the same time. Besides support for the functional relationship between the soil moisture and the root density growth rate, the experiments also suggest that the extension of the maximum rooting depth will stop if the soil moisture at the root tip drops below a threshold value. We show that even a parsimonious one-dimensional water balance model, driven by the water input flux (irrigation), can be convincingly improved by implementing root growth driven by soil moisture availability.
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Rokich, Deanna P., Kathy A. Meney, Kingsley W. Dixon, and K. Sivasithamparam. "The impact of soil disturbance on root development in woodland communities in Western Australia." Australian Journal of Botany 49, no. 2 (2001): 169. http://dx.doi.org/10.1071/bt00015.
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The impact of soil disturbance of the Banksia woodland soil profile and particularly the effect of different reconstructed soil profiles (overburden profile, white profile and yellow profile) and soil ripping within rehabilitation sites, was investigated in terms of root development and architecture for eight species that are key structural elements in Banksia woodland. The aim was to determine the soil environment best suited for root development and architecture likely to contribute to high seedling survival in post-mined sites. Root development and architecture differed significantly between native woodland, and rehabilitation sites. In general, roots were longer in native woodland with low lateral root production (for all species studied) compared to rehabilitation sites where the roots were shorter, tended to divide or lose geotrophy and consisted of numerous laterals. When comparing the different soil profiles in the rehabilitation sites, the commonly reconstructed profile of ‘topsoil over overburden’ (overburden profile) was the least favourable for root development and architecture. Ripping of the soil to 80 cm depth had a positive effect on root growth. There were differences between native woodland and rehabilitation sites, in soil impedance, soil bulk density, soil moisture percentage and organic carbon content. In general, reconstructed soils in rehabilitation sites have (1) soil impedance and soil bulk density values likely to seriously impede root development and architecture, (2) soil moisture percentages higher than those in undisturbed woodland during all months of monitoring and at most depths down to 40 cm and (3) lower organic carbon content than native woodland. When comparing the different soil profiles in rehabilitation sites, the overburden profile (a) had the highest impedance values, (b) was one of the profiles with the highest bulk density values and (c) had the highest soil moisture percentages during most months and at most depths examined. Ripping the soil decreased soil impedance and soil moisture contents. The major conclusion from this study is that soil impedance, which influences water movement, is a key characteristic of soil conditions that are not conducive to the development of deep penetrating root systems. These deep root systems may be directly linked to survival.
6
Sanders, D. C., T. A. Howell, M. M. S. Hile, L. Hodges, and C. J. Phene. "Tomato Root Development Affected by Traveling Trickle Irrigation Rate." HortScience 24, no. 6 (1989): 930–33. http://dx.doi.org/10.21273/hortsci.24.6.930.
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Abstract Root length densities (cm·cm−3) of ‘VF145-B7879’ and ‘UC-82B’ tomatoes (Lycopersicon esculentum Mill.) were determined at three depths and four locations across the planting bed for traveling trickle irrigation treatments applied at 35%, 70%, and 105% of evapotranspiration (ET). Cultivars did not differ in root length densities or in their effect on soil moisture levels. Root length density and soil moisture decreased with soil depth. Although soil moisture was greater in the furrows, the zones of highest root concentration were between the rows of plants and along the edge of the beds. Greater root length density was found in the 35% ET than in the 70% or 105% ET irrigation rate. Chemical names used: 2-(α-naphthoxy)-N,N-diethylpropionamide (napropamide); S-propyl butylethylthiocarbamate (pebulate).
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Dwyer, L. M., B. L. Ma, D. W. Stewart, et al. "Root mass distribution under conventional and conservation tillage." Canadian Journal of Soil Science 76, no. 1 (1996): 23–28. http://dx.doi.org/10.4141/cjss96-004.
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Tillage effects on the soil environment suggest that it may influence rooting depth and root distribution. In this study, corn (Zea mays L.) rooting depth and root mass distribution were compared under conventional and conservation (chisel, ridge, no-) tillage on sandy loam and clay loam soils at Ottawa, Ontario. Root depth and distribution in 0.10-m vertical increments during vegetative growth were estimated using a combination of excavation of the surface horizon (0–0.10 m) and 0.05-m diameter cores obtained in the row and midway between two rows over a 3-yr period. An exponential model was used to fit root mass distribution data normalized with respect to total root density summed over all increments and maximum rooting depth in the profile. Soil moisture, temperature, mechanical resistance and bulk density varied with tillage treatment, but differences were not associated with root mass distribution. Rooting depth varied with soil texture, year and tillage, with increased rooting depth associated with increased tillage and decreased moisture in surface soil layers. In contrast, a common exponential model was found to fit normalized root mass distribution data under all tillage treatments. Our data suggest that simulation of root mass distribution under all tillage practices is possible if rooting depth and root mass density of the surface soil layer are known. Key words: Corn, model fitting, root distribution, tillage, Zea mays
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Khanthavong, Phanthasin, Shin Yabuta, Hidetoshi Asai, Md Amzad Hossain, Isao Akagi, and Jun-Ichi Sakagami. "Root Response to Soil Water Status via Interaction of Crop Genotype and Environment." Agronomy 11, no. 4 (2021): 708. http://dx.doi.org/10.3390/agronomy11040708.
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Flooding and drought are major causes of reductions in crop productivity. Root distribution indicates crop adaptation to water stress. Therefore, we aimed to identify crop roots response based on root distribution under various soil conditions. The root distribution of four crops—maize, millet, sorghum, and rice—was evaluated under continuous soil waterlogging (CSW), moderate soil moisture (MSM), and gradual soil drying (GSD) conditions. Roots extended largely to the shallow soil layer in CSW and grew longer to the deeper soil layer in GSD in maize and sorghum. GSD tended to promote the root and shoot biomass across soil moisture status regardless of the crop species. The change of specific root density in rice and millet was small compared with maize and sorghum between different soil moisture statuses. Crop response in shoot and root biomass to various soil moisture status was highest in maize and lowest in rice among the tested crops as per the regression coefficient. Thus, we describe different root distributions associated with crop plasticity, which signify root spread changes, depending on soil water conditions in different crop genotypes as well as root distributions that vary depending on crop adaptation from anaerobic to aerobic conditions.
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Tan, C. S., and J. M. Fulton. "Water Uptake and Root Distribution by Corn and Tomato at Different Depths." HortScience 20, no. 4 (1985): 686–88. http://dx.doi.org/10.21273/hortsci.20.4.686.
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Abstract Root systems were studied to determine if differences in utilization of soil moisture were associated with the extent and number of roots produced by corn and tomato. Growth room studies for both crops indicated that the reduction in transpiration when the upper portion of the root zone was dry was greater than when the lower portion was dry. Total root length of corn was about twice that of tomato roots. However, no direct relationship between the total amount of root length and transpiration was found. Roots of corn and tomato in the field extended beyond the maximum depth measured (100 cm) between 42 – 46 days after establishment. The spatial density of corn roots was much greater than that of tomato roots, especially as depths increased. This difference possibly explains the use of stored soil moisture by corn. On the other hand, the capacity of tomatoes to extract large amounts of water from the soil cannot be explained by the density and rooting depth. Perhaps this capacity is due to total root surface area differences or high absorption capacity of tomato root system.
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Volkmar, K. M. "Effects of biopores on the growth and N-uptake of wheat at three levels of soil moisture." Canadian Journal of Soil Science 76, no. 4 (1996): 453–58. http://dx.doi.org/10.4141/cjss96-056.
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Roots grow more rapidly through soil spaces such as vacated root channels than through undisturbed soil. This experiment was conducted to determine the extent to which transfer of nutrients is compromised by gaps between the pore wall and the root. Undisturbed cores were obtained from a no-till Dark Brown Chernozemic soil. The cores were divided into three 2.5-cm-thick segments (3.8–6.3 cm, 7.8–10.3 cm, and 11.75–14.25 cm soil layers). The density of 200–500 μm (P200) and 500–1000 μm (P500) diameter pores was visually assessed in each segment. The cores were adjusted to water potentials of − 0.01, − 0.1 and − 1.5 MPa by adding K15NO3-labelled water. Pots containing wheat (Triticum aestivum) plants were placed on top of the cores and the number of roots that appeared at the bottom of the cores, the root length within the cores, and shoot 15N content were measured after 72 h. Small pore (P200) density had no effect on root number at any moisture level. Large pore (P500) density correlated positively with root number at − 0.10 MPa (r2 = 0.57) and − 1.5 Mpa (r2 = 0.68). The equation relating shoot 15N content and root number had a common slope across all moisture treatments, suggesting that the rates of N-uptake per unit root were not compromised by macropore-assisted root growth at the investigated moisture levels. It is unclear if uptake is directly across the pore or via laterals growing outside the pore wall. N-uptake per unit root length of roots growing through soil pores may be compromised at moderate levels of soil moisture. Key words: Biopores, macroporosity, N-uptake, nitrogen, penetrometer resistance, root growth
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Wang, Liqin, David M. Eissenstat, and Dora E. Flores-Alva. "Effects of Soil Temperature and Drought on Root–Soil Respiration in Apple under Field Conditions." HortScience 33, no. 3 (1998): 453a—453. http://dx.doi.org/10.21273/hortsci.33.3.453a.
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Root respiration is very important to root efficiency, root lifespan, and carbon cycling in plant ecosystems. Yet, the effects of soil temperature and moisture on root respiration are poorly understood, especially under field conditions. In this study, we manipulated soil temperature and moisture by six bearing `Red Chief' Delicious/M26 trees near State College, Pa. Soil temperature was elevated 5 °C at 5-cm depth using circulating hot water and stainless steel grids. Soil temperature was monitored using thermocouples and a data logger, and soil moisture was monitored using TDR. Root–soil respiration was determined by static trapping at the soil surface. Heating was conducted from 8 May to 28 Oct. Drought was initiated on 21 Aug. and lasted 2 months. Root–soil respiration was lowest in spring and increased from June to late August. After September, respiration decreased until the experiment ended in November. Root-soil respiration was not correlated with root length density. Heating enhanced root–soil respiration about 15% to 20% in spring (May) and 10% in summer (June–August). After the drought treatment began, heating increased root-soil respiration about 42% in wet soil, but did not influence respiration in dry soil. Heating accentuated the effect of the drought treatment on soil moisture. After 2 months of no irrigation and no rain, soil moisture was reduced 5% in unheated soil and 10% in heated soil. Drought slowed root–soil respiration 17% in unheated soil and 36% in heated soil, mainly because heating increased respiration in wet soil, but compared to the unheated treatment, had no effect in dry soil.
12
Watson, Gary. "Organic Mulch and Grass Competition Influence Tree Root Development." Arboriculture & Urban Forestry 14, no. 8 (1988): 200–203. http://dx.doi.org/10.48044/jauf.1988.048.
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Root density, soil moisture content and soil oxygen diffusion rate (ODR) were measured under three soil surface treatments—grass, organic mulch and bare soil. Seven tree species were tested, green ash, little-leaf linden, pin oak, red oak, sugar maple, red maple and Norway maple. All trees were approximately 20 years old. Elimination of the grass resulted in consistent increases in tree root density at the 0 - 7.5 cm depth, except for the oaks. Application of mulch increased root densities in the soil beneath it. The layer of decomposing organic mulch also provided additional medium for root growth. When compared to the grass treatment, total root surface area was increased up to 195 percent by the mulch treatment and up to 113 percent by the bare soil treatment. Soil moisture was significantly higher in the mulch and the soil beneath it and lowest in the grass treatment. ODR was unaffected by the treatments.
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Nordbotten, Jan Martin, Ignacio Rodriguez-Iturbe, and Michael A. Celia. "Non-uniqueness of evapotranspiration due to spatial heterogeneity of plant species." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 462, no. 2072 (2006): 2359–71. http://dx.doi.org/10.1098/rspa.2005.1641.
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Spatially averaged soil moisture dynamics are studied under seasonally fixed conditions. We consider rainfall as a marked Poisson process, uniformly covering a spatial domain consisting of multiple plant types. Each plant type is considered to have different characteristics in terms of evapotranspiration functions, root-zone depth and rainfall interception. Equations for the evolution of joint probability density functions for individual soil moistures associated with different plant types are developed, and the non-uniqueness of the spatially averaged evapotranspiration function as a function of the average soil moisture is demonstrated and quantified in an example.
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Tu, J. C. "Effects of soil compaction, temperature, and moisture on the development of the Fusarium root rot complex of pea in southwestern Ontario." Phytoprotection 75, no. 3 (2005): 125–31. http://dx.doi.org/10.7202/706059ar.
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The pea root rot complex (Fusarium spp.) is known to be affected by compaction, temperature, and moisture of the soils. This paper reports the effects of these factors on root rot severity and pea (Pisum sativum) growth tested in a controlled environment, using a Fusarium-infested soil collected from a field with a severe root rot history. For each factor, several increments were used. The results showed that in a controlled environment, an increase in soil bulk density due to compaction significantly increased root rot incidence and disease severity, and drastically reduced the fresh weight of pea plants. Stepwise increases in soil temperature from 10 to 30°C resulted in increases in estimated root rot severity and foliar symptom expression. Pea plants grown in soil moisture at 75% of field capacity had significantly lower Fusarium root rot incidence and severity than those grown in soil at 100%, 50% or 25% of field capacity. Pea plants subjected to temporary flooding exhibited an increased root rot incidence and severity as the duration of flooding increased from 1 to 5 d.
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J., M. Mulinge, M. Saha H., G. Mounde L., and A. Wasilwa L. "Effect of Legume Cover Crops on Soil Moisture and Orange Root Distribution." International Journal of Plant & Soil Science 16, no. 4 (2017): 1–11. https://doi.org/10.9734/IJPSS/2017/32934.
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Inadequate rain is a major hindrance to soil moisture and crop root growth in arid and semi-arid areas of Kenya. A field study was conducted in Ganda, Vitengeni and Matuga locations within the coastal lowland region of Kenya from May, 2012 to April, 2015 to evaluate the effects of three leguminous cover crops on soil moisture retention and orange tree feeder root distribution. Treatments included mucuna (<em>Mucuna pruriens</em>), cowpea (<em>Vigna unguiculata</em>), dolichos (<em>Lablab purpureus</em>) cover crops and unplowed fallow of natural vegetation as a control. The experiment was laid out in randomized complete block design (RCBD) and each treatment was replicated four times. Data collected were: soil particle size distribution, soil moisture content and orange dry root density. The data collected was subjected to analysis of variance (ANOVA) using procedures of R statistical analysis version 3.3.2. Mean separation was done using the least significant difference (LSD) value at 5% level of significance. Results indicated that mucuna, dolichos and cowpea cover crops significantly (<em>P</em>=.05) increased soil moisture content. The mucuna treated plots recorded an increase in SMC by 39.0% and 33%, dolichos increased by 34.4% and 28.9% and cowpea by 33.6% and 27.3% at soil depth 0-20 and 20-40 cm, respectively, over their own controls. Mucuna and dolichos significantly (<em>P</em>=.05) increased orange feeder root distribution. Mucuna treated plots supported the highest increase in orange root distribution by 36.5% and 31.8%, dolichos increased by 30.2% and 34.1% while cowpea increased by 18.3% and 18.8% in soil depth 0-20 and 20-40 cm respectively compared to their own control. It can be concluded that the three legumes; mucuna, cowpea and dolichos cover crop improved soil moisture and root distribution in orange production. The overall ranking was as follows: mucuna > dolichos > cowpea. From the finding, the use of mucuna and dolichos cover cropping system is recommended as a soil management practice aimed at improving the orange productivity. Further evaluation on the long term (>3 years) effects of cover crops on soil moisture and orange root distribution under different agro ecological zones is suggested.
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Miller, Gilbert, Ahmad Khalilian, Jeffrey W. Adelberg, Hamid J. Farahani, Richard L. Hassell, and Christina E. Wells. "Grafted Watermelon Root Length Density and Distribution under Different Soil Moisture Treatments." HortScience 48, no. 8 (2013): 1021–26. http://dx.doi.org/10.21273/hortsci.48.8.1021.
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Delineating the depth and extent of the watermelon [Citrullus lanatus (Thumb.) Matsum. & Nak.] root zone assists with proper irrigation management and minimizes nutrient leaching. The objective of this 3-year field study was to measure root distribution and root length density of watermelon (cv. Wrigley) grafted on two different rootstocks (Lagenaria siceraria cv. ‘FR Strong’ and Cucurbita moschata × Cucurbita maxima cv. Chilsung Shintoza) and grown under three soil moisture treatments. Irrigation treatments tested were: no irrigation (NI), briefly irrigated for fertigation and early-season plant establishment; minimally irrigated (MI), irrigated when soil moisture in top 0.30 m of soil fell below 50% available water capacity (AWC); well irrigated (WI), irrigated when soil moisture in top 0.30 m of soil fell below 15% (AWC). Root length density (RLD) was measured from 75-cm-deep soil cores at two locations three times per growing season and a third location at the end of the season. Cores 1 and 2 sample locations were 15 cm to the side of each plant: Core 1 on the same side as the drip tape and Core 2 on the opposite side. At the end of the season, Core 3 was taken 15 cm outside of the bed in bare ground. RLD was significantly greater in the 0- to 30-cm soil depth and dropped dramatically below 30 cm; it was not significantly affected by irrigation treatment or rootstock. Core 1, next to the drip tape, had greater RLD than Core 2, 30 cm from drip tape, but only at the later sampling dates. Roots were found in Core 3 at all depths, but the RLD was significantly less than that measured in Cores 1 and 2. These findings suggest that the effective root zone depth for watermelon is 0 to 30 cm and that the particular scion/rootstock combinations tested in this study do not differ in root system size or location.
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Yu, Bingqin, Changkun Xie, Shize Cai, et al. "Effects of Tree Root Density on Soil Total Porosity and Non-Capillary Porosity Using a Ground-Penetrating Tree Radar Unit in Shanghai, China." Sustainability 10, no. 12 (2018): 4640. http://dx.doi.org/10.3390/su10124640.
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To explore the relationship between arbor root density and corresponding physical soil properties (total porosity, non-capillary porosity, specific weight, bulk density, moisture content, and permeability), noninvasive methods such as Tree Radar Unit (TRU) were utilized to detect the root systems of 10 species of tree that are commonly used in Shanghai green spaces with more than 70% frequency of occurrence. Using TRU and soil investigation, root density and soil porous features were determined for different tree species, depth slices, and distances. The relationships among root density, soil porosity, and non-capillary porosity were identified using variance analysis and regression analysis. The results indicated that root density decreased with increasing distance from the trunk and soil depth. Soil porosity and non-capillary porosity had significantly positive and linear correlations with root density. Compared with lawns, trees such as Zelkova serrata, Koelreuteria paniculata, Cinnamomum camphora, and Metasequoia glyptostroboides had the greatest effects on soil improvement through soil porosity and non-capillary porosity. Due to the spatial distribution of root systems, trees could be divided into three types based on their influence at various soil depths.
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Lindau, Ralf, and Clemens Simmer. "Derivation of a root zone soil moisture algorithm and its application to validate model data." Hydrology Research 36, no. 4-5 (2005): 335–48. http://dx.doi.org/10.2166/nh.2005.0026.
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A retrieval algorithm for soil moisture within the uppermost metre of soil is presented. As calibration data, longtime soil moisture measurements from the former Soviet Union are used. The retrieval works in two steps. First, the distribution of longtime mean soil moisture is derived by using precipitation, soil texture, vegetation density and terrain slope. In a second step, the temporal variability at each location is deduced by using microwave radiation measurements available from satellite together with precipitation and air temperature data. This soil moisture algorithm is applied in Northern and Central Europe to validate a climate simulation from the regional model REMO.
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Thangaraj, M., J. C. O'Toole, and S. K. De Datta. "Root Response to Water Stress in Rainfed Lowland Rice." Experimental Agriculture 26, no. 3 (1990): 287–96. http://dx.doi.org/10.1017/s0014479700018445.
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SUMMARYThe relation between soil mechanical impedance as a result of soil drying, and root system growth (mass and length density) of rice was investigated in greenhouse and field studies. In a greenhouse experiment, soil drying for 16 days increased mechanical impedance in the 0–20 cm soil layer from near 0 to 2.5 MPa, and decreased root growth by 47% compared to the continuously flooded control. Root length density decreased with decreasing soil moisture and increasing soil mechanical impedance. In a lowland field experiment using a sprinkler irrigation gradient treatment for 19 days during the vegetative growth stage, soil mechanical impedance as low as 0.01 MPa inhibited root growth while values greater than 0.3–0.5 MPa decreased root growth and extension by 75%. The relative loss of potential root growth was continued after reflooding. Root length density, measured at flowering, was linearly related to yield.
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Campora, Marina, Anna Palla, Ilaria Gnecco, Rossella Bovolenta, and Roberto Passalacqua. "The laboratory calibration of a soil moisture capacitance probe in sandy soils." Soil and Water Research 15, No. 2 (2020): 75–84. http://dx.doi.org/10.17221/227/2018-swr.
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Determining and mitigating landslide risk is a technical-scientific objective, particularly for the protection and proper territorial management and planning. The slope stability depends on the pore pressure distribution, which is influenced by the saturation front propagation through the unsaturated zone, whose monitoring is useful to understand any possible instabilities. Such monitoring may be undertaken by sensors based on the measurement of the relative dielectric permittivity. Reliable relationships between the measurement and the soil moisture are necessary. The main objective of this study is to assess a laboratory calibration protocol for a specific capacitance sensor (Drill &amp; Drop, Sentek Sensor Technologies). Two monogranular sands have been selected for the calibration purpose. The laboratory tests were performed under three relative density values (D<sub>R</sub> equal to 40%, 60% and 80%) for seven volumetric water content values (θ<sub>v</sub> ranging from 0.00% to 36.26%). Based on the experimental measurements, the soil-specific calibration curves were determined at an assigned relative density value; in particular, a simple power law is adopted to describe the probe’s reading as a function of the volumetric water content. The results point out that the relative density values slightly affect the tests, thus, the soil-specific calibration curves are derived based on a simple regression analysis fitting the whole set of the laboratory tests validated for each sand. The calculated coefficient of determination (R<sup>2</sup> = 0.96÷0.99) and root mean square error (RMSE = 1.4%÷2.8%) values confirm the goodness of fit. In order to propose more general fitting curves, suitable for both the investigated sands, multiple linear regressions are performed by considering θ<sub>v</sub> and the mean grain size, D<sub>50</sub> as independent variables; again, the R<sup>2</sup> and RMSE values equal to 0.97 and 2.41%, respectively, confirm the suitability of the calibration curve. Finally, the laboratory calibration curves are compared with the manufacturer-supplied curves, thus, enhancing the need for the soil-specific calibration.
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Shi, Lei, Liangyan Yang, Biao Peng, et al. "Stability of Loess Slopes Under Different Plant Root Densities and Soil Moisture Contents." Water 16, no. 24 (2024): 3558. https://doi.org/10.3390/w16243558.
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This study conducted an in-depth analysis of the landslide problem in the loess hill and gully area in northern Shaanxi Province, selecting the loess landslide site in Quchaigou, Ganquan County, Yan’an City, as the object to assess the stability of loess slopes under the conditions of different plant root densities and soil moisture contents through field investigation, physical mechanics experiments and numerical simulation of the GeoStudio model. Periploca sepium, a dominant species in the plant community, was selected to simulate the stability of loess slope soils under different root densities and soil water contents. The analysis showed that the stability coefficient of Periploca sepium natural soil root density was 1.263, which was a stable condition, but the stability of the stabilized slopes decreased with the increase in soil root density. Under the condition of 10% soil moisture content, the stability coefficient of the slope body is 1.136, which is a basic stable state, but with the increase in soil moisture content, the stability of the stable slope body decreases clearly. The results show that rainfall and human activities are the main triggering factors for loess landslides, and the vegetation root system has a dual role in landslide stability: on the one hand, it increases the soil shear strength, and on the other hand, it may promote water infiltration and reduce the shear strength. In addition, the high water-holding capacity and permeability anisotropy of loess may lead to a rapid increase in soil deadweight under rainfall conditions, increasing the risk of landslides. The results of this study are of great significance for disaster prevention and mitigation and regional planning and construction, and they also provide a reference for landslide studies in similar geological environments.
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Kuzychenko, Yu A., R. G. Gadzhiumarov, and A. N. Dzhandarov. "Combined tillage with elements of Strip-till technology for maize in the Ciscaucasian zone." Agrarian science 344, no. 1 (2021): 57–59. http://dx.doi.org/10.32634/0869-8155-2021-344-1-57-59.
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Relevance. The combined method of the main tillage, using certain methods of influence on the cultivated layer, forms a certain soil density. During the growing season of corn for grain, this indicator changes depending on the seasonal soil moisture and the intensity of the development of the root system of the plant, which is ultimately related to the yield of the crop. Material and method. The objects of research are two systems of basic tillage for corn for grain according to the predecessor winter wheat in the zone of unstable moisture of the Stavropol Territory using a dump and a combined method of basic tillage with elements of Strip-till technology. Soil: southern calcareous chernozem, slightly humus. The functional dependence of soil density on the supply of productive moisture and the intensity of development of the root system of grain corn was established by the method of the theory of dimensions. The method of fractal geometry was used to determine the degree of filling the soil space with root systems of grain corn under various systems of basic tillage.Results and Conclusions. It was found that the density of the soil is in direct functional dependence on the supply of productive moisture in the cultivated soil layer and the intensity of development of plant roots. The soil density during the seeding and flowering periods is higher by the Strip-till technology in comparison with the traditional one on average over the years by 0.02 g / cm3 and 0.03 g / cm3, respectively, and the moisture reserve in the spring period with Strip-till is 12 mm. The intensity of development of the root system according to the indicator D with the Strip-till system (1.58) by 0.31 units, more than with recommended processing (D = 1.27). The yield of corn for grain using the Strip-till technology is on average 0.22 t / g higher than with the recommended one, at a lower cost by 2395 rubles / ha.
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Gaia-Gomes, João Henrique, Carlos Roberto Pinheiro Junior, Marcos Gervasio Pereira, Wilk Sampaio de Almeida, and Geuzimar Terração Silva. "Variability of soil physical and hydraulic properties along a toposequence in the coastal lowlands of Rio de Janeiro." Ambiente e Agua - An Interdisciplinary Journal of Applied Science 16, no. 1 (2021): 1. http://dx.doi.org/10.4136/ambi-agua.2579.
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Soil physical and hydraulic properties are interdependent, and soil-use planning and management are complicated by the high variability of these attributes. The current study assessed the variability of physical and hydraulic properties of soils along a toposequence located in a forest fragment under spontaneous regeneration in the coastal lowlands of Rio de Janeiro. Four soil profiles were selected, and samples were collected from surface and subsurface horizons for determination of moisture content, bulk density, macroporosity, microporosity, hydraulic conductivity, texture, and soil resistance to penetration (measured using benchtop and field penetrometers). Exploratory and principal component analyses were performed, and descriptive parameters and Pearson’s correlation coefficients were calculated. In A horizons of profiles 3 (Planossolo) and 4 (Gleissolo), clay contents ranged from 59.0 to 577.0 g kg-1, moisture contents from 1.5 to 16.4%, and microporosity from 10.4 to 46.2%, respectively. Field- and laboratory-measured penetration resistances showed a stronger association with profile 1 (Argissolo); however, values were not sufficiently high to limit root development. The variability in soil physical and hydraulic properties in short slopes is high, mainly in terms of hydraulic conductivity, moisture, microporosity, and clay content. The greater variability of soil physical and hydraulic properties in lowland is attributed to clay and silt fractions, microporosity, and moisture content. The increment in clay content with depth increases bulk density and resistance to root penetration.
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Yunqi, Wang, Zhang Yinghua, Wang Zhimin, Tao Hongbin, Zhou Shunli, and Wang Pu. "Effects of winter wheat season tillage on soil properties and yield of summer maize." Plant, Soil and Environment 63, No. 1 (2017): 22–28. http://dx.doi.org/10.17221/692/2016-pse.
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The North China Plain (NCP) serves as China’s second most important maize production region. Rotary tillage, a popular method used in winter wheat/summer maize systems in the region, has adverse effects on maize production. The current study was conducted to determine whether rotary tillage after subsoiling in the winter wheat season (RS) improves the grain-filling rate and yield of summer maize by decreasing soil bulk density, when compared with rotary tillage (R), in the NCP. The RS treatment decreased soil bulk density and increased soil moisture in the summer maize season when compared with the R treatment. Root number under the RS treatment at 8 collar and silking stages was 22.4−35.3% and 8.0−11.7% greater than under the R treatment, respectively. The RS treatment significantly enhanced the grain-filling rate and grain weight as compared to the R treatment. Yield, thousand grain weight, biomass, and harvest index under the RS treatment were 7.7, 7.2, 2.3 and 5.3% higher than under the R treatment. Thousands grain weight was correlated with soil bulk density and soil moisture after silking. Consequently, the increase in grain weight and yield of summer maize resulted from the decrease in soil bulk density and a consequent increase in soil moisture, root number and grain-filling rate.
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Michot, Didier, Zahra Thomas, and Issifou Adam. "Nonstationarity of the electrical resistivity and soil moisture relationship in a heterogeneous soil system: a case study." SOIL 2, no. 2 (2016): 241–55. http://dx.doi.org/10.5194/soil-2-241-2016.
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Abstract. Understanding the role of vegetation in the interface between the atmosphere and groundwater is the most decisive key in analyzing the processes involved in water transfer. The main effect of vegetation is its root water uptake, which significantly modifies the processes involved in water transfer in the vadose zone. This paper focuses on mapping temporal and spatial changes in soil moisture using electrical resistivity tomography (ERT). The main objective is to assess how electrical resistivity (ER) is useful for mapping water distribution along a heterogeneous toposequence crossed by a hedgerow. Ten ERT were performed over the studied period for a 28 m long toposequence and compared to matric potential and groundwater level measurements. Soil volumetric water content (VWC) was predicted with two methods: (i) from ER using the Waxman and Smits model (ii) and from matric potential using an experimental retention curve fitted by a Van Genuchten model. Probability density functions (PDFs) of our set of data show that the largest change in mean ER and matric potential was observed in the topsoil layer. We then analyzed the consistency between ER and point measurements in this layer by extracting the arrays at the junction of ER grids and point measurements. PDFs of ER maps at each monitoring time (from T01 to T10) were also calculated to select the most contrasting distributions, corresponding to the wettest (T06) and driest states (T10). Results of ER were consistent with matric-potential measurements, with two different behaviors for locations inside and outside the root zone. A consistent correlation between VWC values from the Waxman and Smits model and those obtained from the retention curve was observed outside the root zone. The heterogeneous soil system inside the root zone shows a different pattern in this relationship. A shift in the relationship between ER and soil moisture for the locations outside and inside the root zone highlights the nonstationarity between wet and dry periods inside the root zone. The equivocal behavior of this relationship shows the limitation of using ER to predict soil moisture in a heterogeneous soil system. Such systems were actually related to the high hedgerow root density and also to a particular topographical context (ditch and bank) that is encountered in Brittany and throughout northwestern Europe.
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Choi, Hyun-Sug, Curt Rom, and Jason McAfee. "(317) Effects of Different Organic Mulch on Soil Physical Characteristics and Leaf Nutrition in Apple Orchards." HortScience 40, no. 4 (2005): 1027D—1027. http://dx.doi.org/10.21273/hortsci.40.4.1027d.
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Mulch may affect soil chemistry, soil microclimate, biological communities, and tree performance. The trial was conducted to evaluate the effects of different orchard mulches on leaf nutrition, soil moisture, bulk density, root density, and water infiltration for understanding potential use in organic orchards for weed control and as a nutrient resource. Black plastic, hardwood chips, and shredded white paper were applied to three apple cultivars, `Gala', `Jonagold', and `Braeburn' on M.9 rootstocks. A control was sprayed with contact herbicide. Trees grown in hardwood mulch had the highest foliar P and K in year 3. Trees in other mulches showed no difference of leaf nutrition in year 5. All treatments had consistently higher soil moisture than control in year 1, 2, and 4. Mulch did not affect soil bulk density in year 2. The root density was lowest under black plastic mulch in year 2, but was similar in all treatments in year 3. In year 2, water infiltration was fastest in hardwood mulch and control treatments.
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STYPA, M., A. NUNEZ-BARRIOS, D. A. BARRY, M. H. MILLER, and W. A. MITCHELL. "EFFECTS OF SUBSOIL BULK DENSITY, NUTRIENT AVAILABILITY AND SOIL MOISTURE ON CORN ROOT GROWTH IN THE FIELD." Canadian Journal of Soil Science 67, no. 2 (1987): 293–308. http://dx.doi.org/10.4141/cjss87-026.
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In a 4-yr study, root growth in the upper 50 cm of a silt loam soil (Gleyed Melanic Brunisol) was equal to or greater than that in a low-density artificial medium (soil:peat:perlite) in spite of a high bulk density in the soil (1.5 Mg m−3 in the 15-to 45-cm depth). We suggest that, due to the natural structure of the Bm horizon, the resistance to root growth is much less than would be expected from bulk density or penetrometer resistance measurements. Marked increases in P and K fertility in the surface soil had only minor effects on either the total length or distribution of roots although the shoot growth was markedly increased. Neither total root length nor root distribution were altered by irrigation during 1981, the only year a moisture variable was included. During a 2-wk dry period in July, prior to anthesis, soil water potential on the nonirrigated plots decreased to −1.5 MPa in the upper 15 cm and to −0.5 MPa in the 15- to 30-cm layer. Leaf water potential, stomatal conductance and rate of growth during the period were lower on the nonirrigated treatment although final dry matter production was not. The results indicate that corn root growth and distribution in the field are not as sensitive to environmental factors as one would expect from short-term laboratory studies. Key words: Corn, root growth, soil bulk density, fertility, soil water
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Keisuke Sato, Michel, Herdjania Veras de Lima, Pedro Daniel de Oliveira, and Sueli Rodrigues. "Critical soil bulk density for soybean growth in Oxisols." International Agrophysics 29, no. 4 (2015): 441–47. http://dx.doi.org/10.1515/intag-2015-0050.
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Abstract The aim of this study was to evaluate the critical soil bulk density from the soil penetration resistance measurements for soybean root growth in Brazilian Amazon Oxisols. The experiment was carried out in a greenhouse using disturbed soil samples collected from the northwest of Para characterized by different texture. The treatments consisted of a range of soil bulk densities for each soil textural class. Three pots were used for soybean growth of and two for the soil penetration resistance curve. From the fitted model, the critical soil bulk density was determined considering the penetration resistance values of 2 and 3 MPa. After sixty days, plants were cut and root length, dry mass of root, and dry mass of shoots were determined. At higher bulk densities, the increase in soil water content decreased the penetration resistance, allowing unrestricted growth of soybean roots. Regardless of soil texture, the penetration resistance of 2 and 3 MPa had a slight effect on root growth in soil moisture at field capacity and a reduction of 50% in the soybean root growth was achieved at critical soil bulk density of 1.82, 1.75, 1.51, and 1.45 Mg m-3 for the sandy loam, sandy clay loam, clayey, and very clayey soil.
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Magha, Alice Mufur, Primus Azinwi Tamfuh, Lionelle Estelle Mamdem, Marie Christy Shey Yefon, Bertrand Kenzong, and Dieudonné Bitom. "Soil Water Characteristics of Gleysols in the Bamenda (Cameroon) Wetlands and Implications for Agricultural Management Strategies." Applied and Environmental Soil Science 2021 (March 13, 2021): 1–15. http://dx.doi.org/10.1155/2021/6643208.
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Water budgeting in agriculture requires local soil moisture information as crops depend mainly on moisture available at root level. The present paper aims to evaluate the soil moisture characteristics of Gleysols in the Bamenda (Cameroon) wetlands and to evaluate the link between soil moisture content and selected soil characteristics affecting crop production. The work was conducted in the field and laboratory, and data were analyzed by simple descriptive statistics. The main results showed that the soils had a silty clayey to clayey texture, high bulk density, high soil organic carbon content, and high soil organic carbon stocks. The big difference between moisture contents at wilting point and at field capacity testified to very high plant-available water content. Also, the soils displayed very high contents of readily available water and water storage contents. The soil moisture characteristics give sigmoid curves and enabled noting that the Gleysols attain their full water saturation at a range of 57.68 to 91.70% of dry soil. Clay and SOC contents show a significant positive correlation with most of the soil moisture characteristics, indicating that these soil properties are important for soil water retention. Particle density, coarse fragments, and sand contents correlated negatively with the soil moisture characteristics, suggesting that they decrease soil water-holding capacity. The principal component analysis (PCA) enabled reducing 17 variables described to only three principal components (PCs) explaining 73.73% of the total variance; the first PC alone expressed 45.12% of the total variance, associating clay, SOC, and six soil moisture characteristics, thus portraying a deep correlation between these eight variables. Construction of contoured ditches, deep tillage, and raised ridges management techniques during the rainy season while channeling water from nearby water bodies into the farmland, opportunity cropping, and usage of water cans and other irrigation strategies are used during the dry season to combat water constraints.
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Beltrán-Conlag, Andrea Carolina, Marvi Licuy-Chimbo, Zully Margarita López-Grefa, and Ricardo Abril-Saltos. "Capacidad de infiltración de especies forestales en la cuenca alta del río Pindo, Amazonía ecuatoriana." Revista Científica Zambos 4, no. 1 (2025): 376–86. https://doi.org/10.69484/rcz/v4/n1/96.
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This study was carried out in the upper basin of the Pindo River, Luz Adriana sector, Shell parish, Mera canton, Pastaza province, with the objective of identifying forest species that promote water infiltration. The species Piptocoma discolor (Pigue) and Cecropia peltata (Guarumo) were selected through a forest inventory. Data were collected on diameter at breast height (DBH), infiltration tests and edaphic characteristics, including soil texture, bulk density, moisture content and root density. The analyses revealed that there are no significant differences between species in terms of infiltration, bulk density or root density, except for moisture content. In addition, significant correlations were identified: a strong positive relationship between bulk density and moisture content, and between root density with height and DBH. A significant relationship was also observed between infiltration rate and cumulative infiltration. These findings provide new perspectives on the role of forest species in the hydrological regulation of tropical ecosystems.
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Wan, Fa, Wenyong Wu, Renkuan Liao, and Yong Wang. "Spatiotemporal Distribution of Water and Nitrogen in Border Irrigation and Its Relationship with Root Absorption Properties." Water 14, no. 8 (2022): 1253. http://dx.doi.org/10.3390/w14081253.
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The spatiotemporal distribution characteristics of water and nitrogen in the soil profile are essential influencing factors that determine the development of crop root systems. The purpose of this study was to clarify the inter-row and inter-tree variability in soil moisture in the apple root zone, and to determine the effective root diameter ranges of apple trees that influence water and nitrogen absorption. The method used was a 2-year border irrigation experiment carried out in a traditional apple orchard in Zuncun, Shanxi Province, China. Dynamic variations in the soil moisture between trees within the row (perpendicular to the direction of border irrigation) and between rows (along the direction of border irrigation) were continuously measured from 2015 to 2016, and a specific soil profile was excavated to analyze the distribution characteristics of soil water, nitrogen, and roots with different diameters. The results showed obvious variations in soil moisture in the surface soil of 0–30 cm, and the soil moisture content between rows was 5% higher than that between trees within the row. The root length density in the soil between trees within the row was 33.5% higher than that in the soil between rows. Bivariate correlation analysis showed that the correlation between the root system and nitrogen and water was ranked from highest to lowest: total nitrogen (0.741) > nitrate nitrogen (−0.36) > soil moisture (−0.273). The correlation coefficient between trees within the row was higher than that between rows. Lower soil moisture between trees within the row resulted in increased root biomass and more active uptake activity between trees within the row. There were different significant correlations between the specific root diameter and the contents of soil water and nitrogen, showing that the 1.5 mm diameter roots correlated with the water content, whereas the 2.0 mm diameter roots correlated with the nitrogen content. The findings of this study provide a deeper understanding of the absorption mechanism of crop roots for soil water and nitrogen.
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Machado, Lorena, Francisco Sandro Rodrigues Holanda, Alceu Pedrotti, Olavo José Marques Ferreira, Renisson Neponuceno de Araújo Filho, and Marks Melo Moura. "EFFECT OF VETIVER ROOTS ON SOIL RESISTANCE TO PENETRATION IN A TYPIC FLUVIC NEOSSOL IN THE SÃO FRANCISCO RIVERBANK." Revista Caatinga 31, no. 4 (2018): 935–43. http://dx.doi.org/10.1590/1983-21252018v31n416rc.
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ABSTRACT The aim of this study was to evaluate the effect of the root of vetiver grass (Chrysopogon zizanioides (L.) Robert) on the soil Resistance to penetration (RP) in the margins of the lower São Francisco River. Vetiver grass seedlings were planted on the riverbank margins in order to increase soil resistance to erosion processes, and RP assessments were made at soil depths of 0-0.20, 0.20-0.40, and 0.40-0.60 m in different situations (near the plants and within rows). RP data was obtained using an automated penetrometer. Gravimetric moisture data was also collected, as well as particle size data by densimetry, and root density data by the monolith method. The results of the RP, moisture, and root density studies were subjected to analysis of variance (p <0.05) and then the averages were compared by the Tukey test using SISVAR software. The samples next to the vetiver grass showed an average RP of 1793.94 kPa and an average moisture content of 11.78%, statistically differing from that of the sampled points within rows. RP and soil moisture did not differ statistically at the depth assessed. The vetiver grass produced an adequate ground cover, leading to higher water retention and hence a reduced resistance to penetration.
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Bardhan, Abidhan, Raushan Kumar Singh, Sufyan Ghani, Gerasimos Konstantakatos, and Panagiotis G. Asteris. "Modelling Soil Compaction Parameters Using an Enhanced Hybrid Intelligence Paradigm of ANFIS and Improved Grey Wolf Optimiser." Mathematics 11, no. 14 (2023): 3064. http://dx.doi.org/10.3390/math11143064.
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The criteria for measuring soil compaction parameters, such as optimum moisture content and maximum dry density, play an important role in construction projects. On construction sites, base/sub-base soils are compacted at the optimal moisture content to achieve the desirable level of compaction, generally between 95% and 98% of the maximum dry density. The present technique of determining compaction parameters in the laboratory is a time-consuming task. This study proposes an improved hybrid intelligence paradigm as an alternative tool to the laboratory method for estimating the optimum moisture content and maximum dry density of soils. For this purpose, an advanced version of the grey wolf optimiser (GWO) called improved GWO (IGWO) was integrated with an adaptive neuro-fuzzy inference system (ANFIS), which resulted in a high-performance hybrid model named ANFIS-IGWO. Overall, the results indicate that the proposed ANFIS-IGWO model achieved the most precise prediction of the optimum moisture content (degree of correlation = 0.9203 and root mean square error = 0.0635) and maximum dry density (degree of correlation = 0.9050 and root mean square error = 0.0709) of soils. The outcomes of the suggested model are noticeably superior to those attained by other hybrid ANFIS models, which are built with standard GWO, Moth-flame optimisation, slime mould algorithm, and marine predators algorithm. The results indicate that geotechnical engineers can benefit from the newly developed ANFIS-IGWO model during the design stage of civil engineering projects. The developed MATLAB models are also included for determining soil compaction parameters.
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Astutik, Dwi, Prapto Yudono, and Sriyanto Waluyo. "The Growth of Two Cultivars Mung Bean under different Sweet Corn Shelter Density in Sandy Soil Coastal Area." Ilmu Pertanian (Agricultural Science) 2, no. 3 (2018): 106. http://dx.doi.org/10.22146/ipas.26703.
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The experiment had been conducted from August to November 2016 at Samas sandy soil coastal area. The research aimed to determine growth response of mung bean sheltered by various density of sweet corn on coastal sandy soil. The experiment used the nested design with two factors with three replications.The first factor was density of sweet corn as shelter consisting of without shelter (S0), planting space of 15 × 40 cm (S1), and planting space of 30 × 40 cm (S2). The second factor was mung bean cultivars compiled of Vima 1 (V1) and Purworejo local cultivar (V2). The data of soil temperature, soil moisture content at the depth of 10 and 20 cm, soil salt content at 10 and 20 cm depth, leaf fresh and dry weight, root fresh and dry wieght, plant fresh and dry weight were collected. The effect of shelter density was on the leaves dry weight at 6 week after planting (WAP), meanwhile the mung bean cultivars influenced the soil moisture at 10 and 20 cm depth; leaves fresh weight, leaves dry weight, root fresh weight, and plant dry weight at 4 WAP. Vima 1 resulted in significantly higher compared to Purworejo local cultivar on soil moisture content in 10 and 20 cm, leaves fresh and dry weight, root fresh weight, plant fresh and dry weight at 4 WAP. There was interaction between sweet corn shelter density and mung bean cultivar on soil salt content at 10 cm (2 WAP), 20 cm (6 WAP), plant fresh weight at 4 and 6 WAP, and plant dry weight at 6 WAP. The best growth of mung bean was observed under higher level density shelter with 15 × 40 cm square planting space due to the deeper soil layer and lower salt content.
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Konôpka, B., L. Pagès, and C. Doussan. "Impact of soil compaction heterogeneity and moisture on maize (Zea mays L.) root and shoot development." Plant, Soil and Environment 54, No. 12 (2008): 509–19. http://dx.doi.org/10.17221/429-pse.
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Soil compaction heterogeneity and water content are supposed to be decisive factors influencing plant growth. Our experiment focused on simulation of two soil moisture levels (0.16 and 0.19 g/g) plus two levels of clod proportion (30 and 60% volume) and their effects on root and leaf variables of maize (<I>Zea mays</I> L.). We studied number of primary and lateral roots as well as primary root length at the particular soil depths. Statistical tests showed that the decrease rate of the number of roots versus depth was significantly affected by the two studied factors (<I>P</I> < 0.01). Soil moisture and clod occurrence, interactively, affected leaf biomass (<I>P</I> = 0.02). Presence of clods modified root morphological features. Particularly, the diameter of primary roots in the clods was significantly higher than of those grown in fine soil (<I>P</I> < 0.01). For primary roots, which penetrated clods, branching density decreased considerably for the root segments located just after the clods (<I>P</I> = 0.01). Regarding their avoidance to clods and tortuosity, large differences were found between primary roots grown in the contrasting soil environments.
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Srinivas, Jinukala, P. R. Jayan, and N. L. Kalyan Chakravarthi. "Study of Soil and Crop Parameters of Coconut Orchard for Design of Tractor Operated Coconut Basin Lister Cum Fertilizer Applicator." International Journal of Plant & Soil Science 35, no. 11 (2023): 9–15. http://dx.doi.org/10.9734/ijpss/2023/v35i112940.
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Aims: To study the soil and crop parameters of coconut orchard for the design of tractor operated coconut basin lister cum fertilizer applicator.
 Place and Duration of Study: The study was conducted in Instructional Farm, KCAET in the Year 2021.
 Methodology: Soil parameters such as moisture content, bulk density, cone index and shear strength; crop parameters such as trunk diameter and root zone depth of coconut palm were studied using standard procedures to design tractor operated coconut basin lister cum fertilizer applicator.
 Results: The soil moisture content varied from 13.2 to 15.6% with mean of 14.66%. The soil bulk density ranged from 1615 to 1865 kg m-3 with mean of 1696.6 kg m-3. The soil cone index varied from 0.428 to 1.506 N mm-2 with mean of 1.041 N mm-2. The soil shear strength varied from 1.47×10-3 to 3.13×10-3 N mm-2 with mean of 2.31×10-3 N mm-2. The trunk diameter of coconut palm varied from 32.3 to 38.1 cm with mean of 34.74 cm. The root zone depth of coconut palm varied from 13.4 to 15.2 cm with mean of 14.3 cm.
 Conclusion: Soil moisture content, bulk density, cone index and shear strength helped in the design of power requirement, rotor shaft, cutting blades, main shaft etc. of the machine. The trunk diameter of the coconut palm aided in deciding the working width of the machine while the root zone depth assisted in finalizing the operational depth of the machine.
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Liu, Wei Yi, Shao Hui Fan, Guang Lu Liu, and Feng Ying Guan. "The Relationship between Soil Moisture and Root Density under Different Types Phyllostachys edulis Forests in Northern Fujian." Advanced Materials Research 1073-1076 (December 2014): 1090–94. http://dx.doi.org/10.4028/www.scientific.net/amr.1073-1076.1090.
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The soil moisture of three typical P. edulis forests (P. edulis and Cunninghamia lanceolata mixed forest, P. edulis pure forest , P. edulis and broad-leaved tree mixed forest ) in the North of Fujian province were studied in comparison with C. lanceolata pure forest and evergreen broad-leaved forest. Based on the routine observation, characteristics of spatial and temporal change of soil water content were studied. According to the roots distribution which were analyzed on different forest stand, the Linear and relationship model were established about the soil water and roots distribution. Results showed that the forest stand roots density decreasing with increasing soil depth, roots density and spatial distribution of soil moisture are related closely.
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Day, Susan D., John R. Seiler, Richard Kreh, and David W. Smith. "Overlaying compacted or uncompacted construction fill has no negative impact on white oak and sweetgum growth and physiology." Canadian Journal of Forest Research 31, no. 1 (2001): 100–109. http://dx.doi.org/10.1139/x00-145.
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Raising the soil grade, frequently required during building construction, is thought to damage trees and is of concern to foresters responsible for tree protection on such sites. We investigated the effects of applying fill over the roots of 22-year-old white oaks (Quercus alba L.) and 13-year-old sweetgums (Liquidambar styraciflua L.). Treatments included a control (no fill), fill (sandy loam C horizon soil spread 20 cm deep), and compacted fill (same as fill but compacted). Trees with fill had soil held away from trunks or not. After 3 years, there was no consistent treatment effect on growth, chlorophyll fluorescence, or soil respiration in either species. Fill disrupted normal soil moisture patterns. White oak plots with fills had lower soil water contents than controls. In sweetgum plots, soil underlying fill was typically drier than fill layers, whereas control plot soil moisture tended to increase with depth. Fills did not affect overall root density for either species. White oak grew roots well into fill soils, but sweetgum did not, although sweetgum root distribution shifted upwards under fills. Other factors associated with raising the grade, such as soil trafficking and root severance, may be responsible for much of the tree decline attributed to fill.
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SHAINIDZE, OTARI, NODAR BERIDZE, SHOTA LAMPARADZE, et al. "Effect of temperature and moisture on soil pathogen Fusarium solani of lemon in Adjara, Georgia." Journal of Agrometeorology 26, no. 4 (2024): 477–84. https://doi.org/10.54386/jam.v26i4.2685.
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The research was conducted in the 2022 and 2023 seasons in the agrometerology and plant protection laboratory and citrus greenhouse of Batumi Shota Rustaveli State University, the aim of which was groupe and unit role of temperature and soil moisture (SM) content on aggressive soil pathogen F. solani on lemon, also effects of pathogen density and soil moisture on belowground and aboveground morphological traits. In our study, we could find that the both temperature and soil moisture played a decisive role in influencing the root rot disease scenario. As per the disease susceptibility index (DSI), a combination of high temperature (35°C) and low SM (60%) was found to elicit the highest disease susceptibility in lemon. High pathogen colonization was realized in lemon root tissue at all time-points irrespective of genotype, temperature, and SM. Interestingly, this was in contrast to the DSI where no visible symptoms were recorded in the roots or foliage during the initial time-points. For each time-point, the colonization was slightly higher at 35°C than 25°C, while the same did not vary significantly with respect to SM. Shoot biomass was not affected by either pathogen density or soil moisture. However, the two experimental factors have additive effects on the severity of leaf damage. Leaf damage increased with the density of F. solani in the soil, being significantly higher at 60 CFU/g and 120 CFU/g than in control seedlings. Leaf damage was higher at the two extreme soil moisture levels (15% and 100% WHC) than at the two intermediate levels (40% and 50%). In addition, differential expression studies revealed the involvement of defense-related genes, such as endochitinase and chitinase, in the resistant lemon cultivar Meyer, which contribute to retarding root rot disease progression in lemon. In the early stages of infection, especially with low SM. That can be beneficial for farmers and researchers who involve in Citrus
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Michot, D., Z. Thomas, and I. Adam. "Non-stationarity of electrical resistivity and soil moisture relationship in heterogeneous soil system: a case study." SOIL Discussions 2, no. 2 (2015): 955–94. http://dx.doi.org/10.5194/soild-2-955-2015.
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Abstract. Root uptake is the most decisive key in water transfer involving soil and vegetation. It depends on water availability which can be evaluated by punctual measurements. Additionally, surface geophysical methods such as Electrical Resistivity Tomography (ERT) provide larger spatial scales. This paper focuses on investigating temporal and spatial soil moisture changes, along a toposequence crossed by a hedgerow, using ERT and punctual measurements. 10 ERT were performed over the studied period for a 28 m long transect and compared to matric potential and groundwater level measurements. Soil Volumetric Water Content (VWC) was predicted using two methods (i) from ER using Waxman and Smits model (ii) and from matric potential using experimental retention curve fitted by Van Genuchten model. Probability Density Functions (Pdfs) of our set of data show that the largest change, in mean values of ER as well as matric potential, was observed in the topsoil layer. We then analyzed the consistency between ER and punctual measurements in this layer by extracting the arrays in the junction between ER grids and punctual measurements. Pdfs of ER maps at each monitoring time (from T01 to T10) were also calculated to select the more contrasted distributions corresponding to the wettest (T06) and driest states (T10). Results of ER were consistent with matric potential measurements with two different behaviors for locations inside and outside the root zone. A strong correlation (r = 0.9) between VWC values from Waxman and Smits model and those obtained from retention curve was observed outside the root zone. The heterogeneous soil system inside the root zone shows a different pattern in this relationship. The shift in the relationship between ER and soil moisture for the locations outside and inside the root zone highlights the non-stationarity in heterogeneous soil system. Such systems were actually related to the high hedgerow root density and also to a particular topographical context (ditch and bank) which is encountered in Brittany and over north-west of Europe.
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Albergel, C., C. Rüdiger, T. Pellarin, et al. "From near-surface to root-zone soil moisture using an exponential filter: an assessment of the method based on in-situ observations and model simulations." Hydrology and Earth System Sciences Discussions 5, no. 3 (2008): 1603–40. http://dx.doi.org/10.5194/hessd-5-1603-2008.
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Abstract. A long term data acquisition effort of profile soil moisture is under way in southwestern France at 13 automatic weather stations. This ground network was developed in order to validate remote sensing and model soil moisture estimates. In this paper, both those in situ observations and a synthetic data set covering continental France are used to test a simple method to retrieve the root zone soil moisture from a time series of surface soil moisture information. A recursive exponential filter equation using a time constant, T, is used to compute a soil water index. The Nash and Sutcliff coefficient is used as a criterion to optimise the T parameter for each ground station and for each model pixel of the synthetic data set. In general, the soil water indices derived from the surface soil moisture observations and simulations agree well with the reference root-zone soil moisture. Overall, the results show the potential of the exponential filter equation and of its recursive formulation to derive a soil water index from surface soil moisture estimates. This paper further investigates the correlation of the time scale parameter T with soil properties and climate conditions. While no significant relationship could be determined between T and the main soil properties (clay and sand fractions, bulk density and organic matter content), the modelled spatial variability and the observed inter-annual variability of T suggest that a climate effect exists.
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Albergel, C., C. Rüdiger, T. Pellarin, et al. "From near-surface to root-zone soil moisture using an exponential filter: an assessment of the method based on in-situ observations and model simulations." Hydrology and Earth System Sciences 12, no. 6 (2008): 1323–37. http://dx.doi.org/10.5194/hess-12-1323-2008.
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Abstract. A long term data acquisition effort of profile soil moisture is under way in southwestern France at 13 automated weather stations. This ground network was developed in order to validate remote sensing and model soil moisture estimates. In this paper, both those in situ observations and a synthetic data set covering continental France are used to test a simple method to retrieve root zone soil moisture from a time series of surface soil moisture information. A recursive exponential filter equation using a time constant, T, is used to compute a soil water index. The Nash and Sutcliff coefficient is used as a criterion to optimise the T parameter for each ground station and for each model pixel of the synthetic data set. In general, the soil water indices derived from the surface soil moisture observations and simulations agree well with the reference root-zone soil moisture. Overall, the results show the potential of the exponential filter equation and of its recursive formulation to derive a soil water index from surface soil moisture estimates. This paper further investigates the correlation of the time scale parameter T with soil properties and climate conditions. While no significant relationship could be determined between T and the main soil properties (clay and sand fractions, bulk density and organic matter content), the modelled spatial variability and the observed inter-annual variability of T suggest that a weak climate effect may exist.
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Watson, Gary, and Gary Kupkowski. "Effects of a Deep Layer of Mulch on the Soil Environment and Tree Root Growth." Arboriculture & Urban Forestry 17, no. 9 (1991): 242–45. http://dx.doi.org/10.48044/jauf.1991.056.
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After two years, no detrimental effects were found from application of 0.45 m (18 in) of wood chip mulch over soil in which the roots of trees were growing. Soil temperature, moisture and oxygen diffusion rate (ODR) were similar to soil without mulch. Root density in mulched soil was not different from unmulched soil; additional roots had proliferated into the mulch.
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Valicheski, Romano Roberto, Suzi Mari Brandelero, David José Miquelutti, Sidnei Leandro K.Stürmer, Antonio Luis Tramonti, and Marcos Cesar Franzão. "Absorption of primary macronutrients and soybean growth at different compactation densities and moisture levels in a silt loam soil." Revista Ceres 63, no. 2 (2016): 223–31. http://dx.doi.org/10.1590/0034-737x201663020014.
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ABSTRACT Soybean cultivation is increasing rapidly in the region of Alto Vale do Itajaí, State of Santa Catarina, where there is a predominance of silt soils. The objective of this work was to evaluate the content of primary macronutrients in shoots and shoot and root vegetative growth of soybean (Glicine max L. Merrill) grown in a silt-loam soil under different compactation densities and moisture levels. A randomized block design in a 4x4 factorial arrangement was used, with four compactation densities: 1.00; 1.20; 1.40 and 1.60 Mg m-3, and four soil moisture levels: 0.130; 0.160; 0.190 and 0.220 kg kg-1 and four replications. Each pot consisted of the overlapping of three 150-mm PVC rings, where soil was maintained in the higher and lower part of the pot with a density of 1.00 Mg m-3 and in the intermediate ring, the compactation densities were increased. Values of soil density higher than 120 Mg m-3 negatively affected N, P and K uptake by soybean plants, as well as the plant mass of the shoots and roots. The higher levels of soil moisture reduced the compaction effect and promoted better absorption of P and K.
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Mehra, Promil, Pankaj Kumar, Nanthi Bolan, Jack Desbiolles, Susan Orgill, and Matthew D. Denton. "Changes in soil-pores and wheat root geometry due to strategic tillage in a no-tillage cropping system." Soil Research 59, no. 1 (2021): 83. http://dx.doi.org/10.1071/sr20010.
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Tillage management can influence soil physical properties such as soil strength, moisture content, temperature, nutrient and oxygen availability, which in turn can affect crop growth during the early establishment phase. However, a short-term ‘strategic’ conventional tillage (CT) shift in tillage practice in a continuous no-tillage (NT) cropping system may change the soil-pore and root geometry. This study identifies the impact of a tillage regime shift on the belowground soil-pore and root geometry. Micro X-ray computed tomography (µXCT) was used to quantify, measure and compare the soil-pore and root architecture associated with the impact of tillage shift across different plant growth stages. Soil porosity was 12.2% higher under CT in the top 0–100 mm and 7.4% in the bottom 100–200 mm of the soil core compared with NT. Soil-pore distribution, i.e. macroporosity (&gt;75 μm), was 13.4% higher under CT, but mesoporosity (30–75 μm) was 9.6% higher under NT. The vertical distributions of root biomass and root architecture measurements (i.e. root length density) in undisturbed soil cores were 9.6% higher under the NT and 8.7% higher under the CT system respectively. These results suggest that low soil disturbance under the continuous NT system may have encouraged accumulation of more root biomass in the top 100 mm depth, thus developing better soil structure. Overall, µXCT image analyses of soil cores indicated that this tillage shift affected the soil total carbon, due to the significantly higher soil-pore (i.e. pore surface area, porosity and average pore size area) and root architecture (i.e. root length density, root surface density and root biomass) measurements under the CT system.
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M. H., Abdel-Aal. "Effect of tillage practices at different levels of soil moisture on some soil properties and maize productivity." International Journal of Agricultural Invention 5, no. 01 (2020): 1–15. http://dx.doi.org/10.46492/ijai/2020.5.1.1.
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A field experiment was carried out during the early summer seasons of 2018, at Agricultural Research Centre (ARC) Giza, Egypt. This study aims to examine the effect of three tillage treatments under three different moisture contents on some soil properties and on maize crop production. The experiments included three moisture contents of (MC1, 27.2 %), (MC2, 15.4 %) and (MC3, 7.2 %); as well as three tillage treatments, no-tillage control (NT), minimum tillage (MT) and conventional tillage (CT). The experimental was laid out in split-split plot design with four replications. The results showed that, there was significant effect of tillage at different moisture levels on soil physical and chemical properties. It was also indicated that the effect of tillage practices was significantly on soil bulk density, total porosity, hydraulic conductivity and moisture constants, where the conventional tillage at soil moisture level 15.4% (MC2) helped in improving soil bulk density, hydraulic conductivity and total porosity. Soil organic C, cations exchange capacity CEC, available N, P and K were improved in the soil surface layer of NT and decreased with depth. Clod mean weight diameter of soil was improved with 15.4-% of soil moisture content regardless of tillage depth and enhanced root proliferation by increasing density roots compared with minimum and no tillage in maize plant. The grain yields of maize were improving more under conventional tillage at moisture content 15.4% compared with other treatments. It was found that plant height and roots value increased by using conventional tillage compared with other tillage treatments.
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Abdel-Aal, M. H. "Effect of tillage practices at different levels of soil moisture on some soil properties and maize productivity." Effect of tillage practices at different levels of soil moisture on some soil properties and maize productivity 5, no. 1 (2020): 1–15. https://doi.org/10.46492/IJAI/2020.5.1.1.
Full textAbstract:
A field experiment was carried out during the early summer seasons of 2018, at Agricultural Research Centre (ARC) Giza, Egypt. This study aims to examine the effect of three tillage treatments under three different moisture contents on some soil properties and on maize crop production. The experiments included three moisture contents of (MC1, 27.2 %), (MC2, 15.4 %) and (MC3, 7.2 %); as well as three tillage treatments, no-tillage control (NT), minimum tillage (MT) and conventional tillage (CT). The experimental was laid out in split-split plot design with four replications. The results showed that, there was significant effect of tillage at different moisture levels on soil physical and chemical properties. It was also indicated that the effect of tillage practices was significantly on soil bulk density, total porosity, hydraulic conductivity and moisture constants, where the conventional tillage at soil moisture level 15.4% (MC2) helped in improving soil bulk density, hydraulic conductivity and total porosity. Soil organic C, cations exchange capacity CEC, available N, P and K were improved in the soil surface layer of NT and decreased with depth. Clod mean weight diameter of soil was improved with 15.4-% of soil moisture content regardless of tillage depth and enhanced root proliferation by increasing density roots compared with minimum and no tillage in maize plant. The grain yields of maize were improving more under conventional tillage at moisture content 15.4% compared with other treatments. It was found that plant height and roots value increased by using conventional tillage compared with other tillage treatments.
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Zhang, Shuzhen, Yuqi Wei, Nan Liu, et al. "Mowing Facilitated Shoot and Root Litter Decomposition Compared with Grazing." Plants 11, no. 7 (2022): 846. http://dx.doi.org/10.3390/plants11070846.
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Shoot and root litter are two major sources of soil organic carbon, and their decomposition is a crucial nutrient cycling process in the ecosystem. Altitude and land use could affect litter decomposition by changing the environment in mountain grassland ecosystems. However, few studies have investigated the effects of land use on litter decomposition in different altitudes. We examined how land-use type (mowing vs. grazing) affected shoot and root litter decomposition of a dominant grass (Bromus inermis) in mountain grasslands with two different altitudes in northwest China. Litterbags with 6 g of shoot or root were fixed in the plots to decompose for one year. The mass loss rate of the litter, and the environmental attributes related to decomposition, were measured. Litter decomposed faster in mowing than grazing plots, resulting from the higher plant cover and soil moisture but lower bulk density, which might promote soil microbial activities. Increased altitude promoted litter decomposition, and was positively correlated with soil moisture, soil organic carbon (SOC), and β-xylosidase activity. Our results highlight the diverse influences of land-use type on litter decomposition in different altitudes. The positive effects of mowing on shoot decomposition were stronger in lower than higher altitude compared to grazing due to the stronger responses of the plant (e.g., litter and aboveground biomass) and soil (e.g., soil moisture, soil bulk density, and SOC). Soil nutrients (e.g., SOC and soil total nitrogen) seemed to play essential roles in root decomposition, which was increased in mowing plots at lower altitude and vice versa at higher altitude. Therefore, grazing significantly decreased root mass loss at higher altitude, but slightly increased at lower altitude compared to mowing. Our results indicated that the land use might variously regulate the innate differences of the plant and edaphic conditions along an altitude gradient, exerting complex impacts in litter decomposition and further influencing carbon and nutrient cycling in mountain grasslands.
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Smith, Karen, Peter May, and Gregory Moore. "The Influence of Compaction and Soil Strength on the Establishment of Four Australian Landscape Trees." Arboriculture & Urban Forestry 27, no. 1 (2001): 1–7. http://dx.doi.org/10.48044/jauf.2001.001.
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Two experiments were conducted to test the hypothesis that trees able to establish in urban soils will have a higher-than-average tolerance to the higher mechanical impedance and soil strength of compacted soils. Experiment 1 tested the ability of the roots of Corymbia metadata (spotted gum, syn. Eucalyptus maculata), Lophostetnon confertus (brush box), Corymbia ficijolia (red flowering gum, syn. Eucalyptus ficifolia), and Agonis flexuosa (willow myrtle) seedlings to penetrate a sandy loam soil compacted to bulk densities of 1.4 and 1.8 mg • m~3 at 13% gravimetric moisture content. While roots of all species were able to penetrate the soil at the higher bulk density, total root penetration depth was reduced by 60% in all four species. Experiment 2 tested the ability of Corymbia maculata and C. ficijolia to penetrate soil compacted at bulk densities 1.4, 1.6, and 1.8 mg • m~3 at two moisture levels, 7% and 10% gravimetric moisture. At 7% moisture, both species were able to penetrate soil compacted to 1.4 and 1.6 mg • rrr3, but neither species was able to successfully penetrate soil compacted to 1.8 mg • m"3. At 10% moisture, both species were able to penetrate soil compacted to 1.4 and 1.6 mg • m~3. They also were able to successfully penetrate soil compacted to 1.8 mg • nr3, although with significantly less depth of penetration than at the two lower bulk densities.
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Fu, Jiang-Tao, Xia-Song Hu, Xi-Lai Li, Ji-Mei Zhao, Guang-Yan Xing, and Chang-Yi Liu. "Impact of Meadow Degradations on the Probabilistic Distribution Patterns of Physical and Mechanical Indices of Rooted Soil in the Upper Regions of the Yellow River, China." Water 16, no. 9 (2024): 1205. http://dx.doi.org/10.3390/w16091205.
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The shear strength (particularly soil cohesion) of rooted soil is an important parameter that reflects the true erodibility of meadows, particularly in meadows experiencing different degrees of degradation, ranging from undegraded (UD) through to lightly degraded (LD) and from moderately degraded (MD) to heavily degraded (HD). The cohesion of rooted soil is controlled not only by the soil moisture content and its natural density, but also by roots (including not only their density, spatial distribution, and diameters, but also their tensile strength). This study aimed to improve the current understanding of the erosion resistance of rooted soil and elucidate the impact of meadow degradation on the physical–mechanical indices of rooted soil. Based on this discussion, a one-way analysis of variance was performed at significance levels of 0.05 and 0.01 to test the impact of degradation on the physical–mechanical indices of rooted soil across degradation. Furthermore, the probabilistic distributions of the physical–mechanical indices were described using normal, gamma, Weibull, and generalized extreme values (GEV). The Kolmogorov–Smirnov (KS) test was used to identify the optimal distribution based on p-values and the Pearson correlation coefficient was used to quantify the correlation between the cohesion of rooted soil and other indices. The one-way ANOVA indicated that the soil’s natural density and soil moisture content decreased firstly, followed by an increase, the root amount and cohesion decreased, the root content experienced an initial increasing and then decreasing trend, and the internal friction angle exhibited a stepwise increasing trend. The four distributions sufficiently described the actual distribution of data on the physical–mechanical indices of rooted soil, except for the internal friction angle in UD and MD soils and the soil moisture content in MD soil. Additionally, the KS tests showed that the optimal distribution depended on both the physical–mechanical indices themselves and the degree of degradation. The Pearson correlation analysis showed that the correlation between cohesion and the other physical–mechanical indices varied considerably depending on the degree of degradation.