Letteratura scientifica selezionata sul tema "Canopy decline"
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Articoli di riviste sul tema "Canopy decline"
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Moore, T. L., L. E. Valentine, M. D. Craig, G. E. StJ Hardy e P. A. Fleming. "Do woodland birds prefer to forage in healthy Eucalyptus wandoo trees?" Australian Journal of Zoology 61, n. 3 (2013): 187. http://dx.doi.org/10.1071/zo13045.
Testo completoAbstract (sommario):
Globally, many forests and woodlands are in decline. The marked loss of canopy foliage typical of these declines results in reduced foraging resources (e.g. nectar, pollen, and insects) and, subsequently, can reduce habitat quality for woodland birds. In south-west Western Australia, patches of Eucalyptus wandoo woodlands have shown a decline in condition since at least 2002. We investigated how changes in E. wandoo condition affect the woodland bird community. Foraging activities of three bird species were recorded for 20 sites in Dryandra State Forest and Wandoo Conservation Park either by conducting watches on focal trees (‘sitting’ method), or following individuals through the woodland (‘following’ method). Condition assessments of trees used by the birds were compared with those for trees available at the study site. Weebills (Smicrornis brevirostris; canopy insectivore) displayed preference for healthy trees (low amounts of canopy dieback), whereas rufous treecreepers (Climacteris rufa; bark-foraging insectivore) preferred trees with a higher proportion of dead branches. Yellow-plumed honeyeaters (Lichenostomus ornatus; insectivore/nectarivore) foraged in older, larger E. wandoo trees having full canopies with few signs of tree decline. Tree declines, such as that happening in E. wandoo, alter the foraging resources and habitat available to woodland birds.
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Jaikumar, Nikhil S., Samantha S. Stutz, Samuel B. Fernandes, Andrew D. B. Leakey, Carl J. Bernacchi, Patrick J. Brown e Stephen P. Long. "Can improved canopy light transmission ameliorate loss of photosynthetic efficiency in the shade? An investigation of natural variation in Sorghum bicolor". Journal of Experimental Botany 72, n. 13 (29 aprile 2021): 4965–80. http://dx.doi.org/10.1093/jxb/erab176.
Testo completoAbstract (sommario):
Abstract Previous studies have found that maximum quantum yield of CO2 assimilation (Φ CO2,max,app) declines in lower canopies of maize and miscanthus, a maladaptive response to self-shading. These observations were limited to single genotypes, leaving it unclear whether the maladaptive shade response is a general property of this C4 grass tribe, the Andropogoneae. We explored the generality of this maladaptation by testing the hypothesis that erect leaf forms (erectophiles), which allow more light into the lower canopy, suffer less of a decline in photosynthetic efficiency than drooping leaf (planophile) forms. On average, Φ CO2,max,app declined 27% in lower canopy leaves across 35 accessions, but the decline was over twice as great in planophiles than in erectophiles. The loss of photosynthetic efficiency involved a decoupling between electron transport and assimilation. This was not associated with increased bundle sheath leakage, based on 13C measurements. In both planophiles and erectophiles, shaded leaves had greater leaf absorptivity and lower activities of key C4 enzymes than sun leaves. The erectophile form is considered more productive because it allows a more effective distribution of light through the canopy to support photosynthesis. We show that in sorghum, it provides a second benefit, maintenance of higher Φ CO2,max,app to support efficient use of that light resource.
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LeBlanc, David C., e Dudley J. Raynal. "Red spruce decline on Whiteface Mountain, New York. II. Relationships between apical and radial growth decline". Canadian Journal of Forest Research 20, n. 9 (1 settembre 1990): 1415–21. http://dx.doi.org/10.1139/x90-187.
Testo completoAbstract (sommario):
Understanding the relationship between apical and radial growth decline can contribute toward the evaluation of hypotheses regarding causal mechanisms of red spruce decline. The etiology of red spruce decline in montane spruce-fir forests of the northeastern United States includes loss of foliage at branch apices, crown dieback, and unreversed radial growth decline since the 1960s. Demographic analyses of crown damage and radial growth decline for red spruce on Whiteface Mountain, New York, indicate that large, canopy-emergent trees with exposed crowns exhibit greater decline than codominant trees within an intact canopy. In this paper, radial growth decline is shown to have been coincident with decreased apical growth and increased incidence of injury to terminal leaders. Incidence of leader mortality is greatest for canopy-emergent red spruce or trees with exposed crowns, similar to patterns described for radial growth. This relationship suggests that the post-1960 decline of red spruce on Whiteface Mountain is caused, at least in part, by stresses that act directly on the crown.
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Misik, Tamás, Imre Kárász e Béla Tóthmérész. "Understory Development in an Oak Forest in Northern -Hungary: the Subcanopy Layer". Acta Silvatica et Lignaria Hungarica 10, n. 1 (1 settembre 2014): 9–21. http://dx.doi.org/10.2478/aslh-2014-0001.
Testo completoAbstract (sommario):
Abstract Structural changes in the shrub layer were analysed in a Hungarian oak forest after the oak decline pandemics. This paper focuses on the following questions: (1) which of the woody species tolerated better the forest conditions after oak decline? (2) What are the ecological factors that explain the successful response of woody species to changes in light and thermal conditions? In the monitoring plot, the structural condition of specimens only above 8.0 m was observed. After the appearance of oak decline some Acer campestre, Cornus mas and Acer tataricum specimens appeared that reached between 8.0-13.0 m in height. Significant differences were revealed between top canopy density and foliage cover of the subcanopy and between top canopy density and mean cover of field maple. The findings of the study indicate that the forest responded to oak decline with significant structural rearrangement in the shrub layer and that three woody species compensated for the remarkable foliage loss in the top canopy. These species formed a second crown layer directly below the canopy formed by oaks.
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Sands, PJ. "Modelling Canopy Production. I. Optimal Distribution of Photosynthetic Resources". Functional Plant Biology 22, n. 4 (1995): 593. http://dx.doi.org/10.1071/pp9950593.
Testo completoAbstract (sommario):
On the basis of detailed numerical simulations, Field (1983. Oecologia 56, 341-347) stated that total canopy photosynthesis will be a maximum for a fixed total canopy leaf nitrogen provided the derivative δA/δN, where A is photosynthetic rate and N is leaf nitrogen concentration, has the same value throughout the canopy. This paper uses the calculus of variations to formally prove Field's assertion. It shows that if the single-leaf light response is a first-degree homogeneous function of both light-saturated photosynthetic rate Amax and intensity I of photosynthetically active radiation and if Amax is linearly related to N, then the optimal distribution of leaf nitrogen is linearly related to the decline in I with canopy depth, and Amax is proportional to this decline. The nature of photosynthetic gains due to optimisation of canopy nitrogen distribution is illustrated numerically for a simple model canopy. It is found that, for canopies with fixed mean leaf nitrogen, canopy photosynthesis is approximately proportional to canopy leaf area index (LAI), and the gain due to canopy optimisation compared with a uniform canopy is small for shallow canopies but pronounced for deep canopies. It is also found that, for canopies with fixed total leaf nitrogen, there is a canopy LAI which maximises canopy photosynthesis, and that this LAI and the corresponding canopy photosynthesis are approximately proportional to total canopy nitrogen.
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Berdugo, Monica B., e Martin Dovciak. "Bryophytes in fir waves: Forest canopy indicator species and functional diversity decline in canopy gaps". Journal of Vegetation Science 30, n. 2 (marzo 2019): 235–46. http://dx.doi.org/10.1111/jvs.12718.
Testo completo
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O'Grady, A. P., D. Worledge, A. Wilkinson e M. Battaglia. "Photosynthesis and respiration decline with light intensity in dominant and suppressed Eucalyptus globulus canopies". Functional Plant Biology 35, n. 6 (2008): 439. http://dx.doi.org/10.1071/fp08127.
Testo completoAbstract (sommario):
Within canopy gradients in light-saturated photosynthesis (Amax), foliar nitrogen ([N]area) and leaf dark respiration (R15) were studied in the canopies of dominant and suppressed trees within an even-aged (4-year-old) Eucalyptus globulus (Labill) stand in southern Tasmania. Despite being an even-aged stand growing in a relatively uniform environment with respect to nutrient and water availability, the stand exhibited considerable structural complexity. Diameter at 1.3 m ranged between 3 cm and 21 cm, trees average 12 m height and stand leaf area index was ~6 m2 m–2 leading to strong gradients in light availability. We were interested in understanding the processes governing canopy production in trees of contrasting dominance classes. Vertical gradients in photosynthesis and foliar respiration were studied within the canopies of dominant and suppressed trees during 2006 and 2007. Amax varied from ~18 μmol m–2 s–1 in the upper canopy to 3 μmol m–2 s–1 at lower canopy positions. On average, Amax were higher in the dominant trees than in the suppressed trees. However, at any given height, Amax were similar in suppressed and dominant trees and were strongly related to leaf nitrogen content. Dark respiration varied from ~1.4 μmol m–2 s–1 in the upper canopy to 0.2 μmol m–2 s–1 in the lower canopy positions. In contrast to the patterns for Amax, dark respiration rates in the suppressed trees were higher than dominant trees at similar canopy positions. Respiration rates were also strongly related to [N]area and to Amax.
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Miranda, Eduardo Jacusiel, George L. Vourlitis, Nicolau Priante Filho, Pedro Correto Priante, José Holanda Campelo, George Sanches Suli, Clóvis Lasta Fritzen, Francisco de Almeida Lobo e Shozo Shiraiwa. "Seasonal variation in the leaf gas exchange of tropical forest trees in the rain forest–savanna transition of the southern Amazon Basin". Journal of Tropical Ecology 21, n. 4 (27 giugno 2005): 451–60. http://dx.doi.org/10.1017/s0266467405002427.
Testo completoAbstract (sommario):
The photosynthetic light response of Amazonian semi-deciduous forest trees of the rain forest–savanna transition near Sinop Mato Grosso, Brazil was measured between July 2000 and September 2003 to test the hypothesis that the photosynthetic capacity of trees acclimated to different growth light environments will decline during the dry season. Maximum photosynthesis (Amax) and stomatal conductance (gmax) were significantly higher during the wet season; however, the physiological response to drought was not a clear function of growth light environment. For some species, such as Psychotria sp. growing in the mid-canopy, internal leaf CO2 concentration (Ci) was >30% lower during the dry season suggesting that declines in Amax were caused in part by stomatal limitations to CO2 diffusion. For other species, such as Brosimum lactescens growing at the top of the canopy, Tovomita schomburgkii growing in the mid-canopy, and Dinizia excelsa growing in the understorey, dry season Ci declined by <20% suggesting that factors independent of CO2 diffusion were more important in limiting Amax. Dry-season declines in gmax appeared to be important for maintaining a more consistent leaf water potential for some species (T. schomburgkii and D. excelsa) but not others (Psychotria sp.). These results indicate that while seasonal drought exerts an important limitation on the physiological capacity of semi-deciduous Amazonian forest trees, the mechanism of this limitation may differ between species.
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Strauss, Megan K. L., e Craig Packer. "Did the elephant and giraffe mediate change in the prevalence of palatable species in an East African Acacia woodland?" Journal of Tropical Ecology 31, n. 1 (8 dicembre 2014): 1–12. http://dx.doi.org/10.1017/s0266467414000625.
Testo completoAbstract (sommario):
Abstract:We report on a 2009 survey of Acacia woodlands in the Seronera area of central Serengeti, Tanzania, and compare the results to previous surveys from the 1970s–1980s. We document a substantial change in woodland structure and composition. From 1978 to 2009, woody plant density (mean ± SD) declined from 255 ± 35 trees ha−1 to 147 ± 14 trees ha−1. Canopy cover declined from 15.1 ± 1.9% to 5.7 ± 0.6%. Canopy volume declined from 1810 ± 207 m3 ha−1 to 1410 ± 121 m3 ha−1. A 19% increase in the relative canopy volume of Acacia robusta, a species avoided by the giraffe, represents a sharp decline in the quality of the giraffe's food supply, which was last comprehensively assessed in 1978. We examine these changes in the context of Pellew's 1983 woodland dynamics model describing the impacts of elephant, giraffe and fire on an Acacia tortilis tree population and determine that our data are qualitatively consistent with this model. We hypothesize that selective elephant and giraffe browsing has contributed to an increase in the relative dominance of unpalatable species, consistent with Pellew's predictions.
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Schaberg, Paul G., Paul E. Hennon, David V. D'Amore, Gary J. Hawley e Catherine H. Borer. "Seasonal differences in freezing tolerance of yellow-cedar and western hemlock trees at a site affected by yellow-cedar decline". Canadian Journal of Forest Research 35, n. 8 (1 agosto 2005): 2065–70. http://dx.doi.org/10.1139/x05-131.
Testo completoAbstract (sommario):
To assess whether inadequate cold hardiness could be a contributor to yellow-cedar (Chamaecyparis nootkatensis (D. Don) Spach) decline, we measured the freezing tolerance of foliage from yellow-cedar trees in closed-canopy (nondeclining) and open-canopy (declining at elevations below 130 m) stands at three sites along an elevational gradient in the heart of the decline in southeastern Alaska. Foliar freezing tolerance was also assessed for sympatric nondeclining western hemlock (Tsuga heterophylla (Raf.) Sarg.). Measurements were made in the fall, winter, and spring to evaluate if seasonal differences in cold hardiness help explain species-specific injury. Significant differences in freezing tolerance attributable to site, canopy closure, species, and the interaction of canopy closure and species were each detected for at least one sample period. However, only two results were consistent with field reports of yellow-cedar decline: (1) between winter and spring measurements, yellow-cedar trees dehardened almost 13 °C more than western hemlock trees, so that yellow-cedar trees were more vulnerable to foliar freezing injury in spring than western hemlock; and (2) stands below 130 m appeared more vulnerable to freezing injury than stands above 130 m.
Tesi sul tema "Canopy decline"
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Croft, Sonia Julie. "Canopy dieback and decline in pink gums, Eucalyptus fasciculosa, F.Muell in the Mt Lofty Ranges and adjoining plains". Thesis, 2017. http://hdl.handle.net/2440/111991.
Testo completoAbstract (sommario):
In Australia, widespread decline of Eucalyptus species has been occurring largely since the 1970s. In southern Australia, pink gums (Eucalyptus fasciculosa F. Muell) occur within a restricted area, and have been assigned a conservation rating due to perceived canopy decline. This study aimed to describe the population structure and canopy condition of pink gums in the Mt Lofty Ranges and surrounding plains, and to distinguish between causes of short-term dieback and long-term decline. I hypothesised that decline in pink gum woodlands was most likely to be because of one or more of the following: (1) long-term and continuous mistletoe infection; (2) declining annual rainfall commencing several decades ago, particularly for trees growing in deep sandy soils and (3) reduced groundwater availability that commenced well before 2003. Dieback was most likely to be associated with insect attack. Within the study region, pink gums occupy a wide gradient of rainfall, soil type and topography. A regional survey between 2009 and 2012 recorded that the mean canopy intactness for 2814 pink gums was 70%, but canopy condition varied widely between, and often within, pink gum woodlands. The habitat variables that contributed most to variation in canopy intactness were mistletoe prevalence, followed by insect damage. In almost 30% of populations there were no seedling pink gums. Between 2009 and 2011, mean canopy intactness of 1751 pink gums declined from 71% to 66%, 21 pink gums died, and no recruitment was recorded. Leaf production in pink gums was greatest during the above-average rainfall in the summer of 2010/11. This was followed by localised high levels of gum leaf skeletoniser (Uraba lugens) and lerp (Cardiaspina densitexta). Canopy loss from these insects was concluded to be cyclic and short term. The canopy intactness of 161 pink gums and their mistletoe load, was recorded between 2003 and 2015. The net number of live mistletoes declined by two thirds, with the greatest net decline occurring during three consecutive below-average rainfall years. While the mean canopy intactness of pink gums was the same in 2003 and 2015, pink gums whose canopy comprised at least 20% mistletoe, recorded significant canopy loss during consecutive years of below-average rainfall. Comparison of aerial photographs between 1949 and 2005 for two pink gum woodlands indicated that canopy decline began in the mid-1970s, coinciding with lowering of groundwater levels and increased mistletoe infection, and the beginning of an ongoing decline in autumn rainfall. These pink gums occurred on deep sands with approximately 500 mm annual rainfall, a habitat that would be more prone to autumn soil drying. Because of the lack of recent recruitment at many pink gum woodlands, it may be necessary to restore and/or maintain populations with revegetation. A glasshouse experiment involving manipulating water supply to three pink gum provenances showed that there was genetic variation between provenances. This will provide the option in revegetation projects, of matching selection of seed sources to projected climate change. However, in a separate six year study, 12 of 34 pink gum juveniles remained the same height, with insect defoliators and competition from nearby trees considered largely responsible for suppressing growth. The potential slow growth rate of pink gums should be incorporated into revegetation planning. This study provided evidence that pink gums may be at least partially groundwater dependent. Within the same woodland, where all habitat factors other than depth to groundwater appeared to be equal, pink gums sited over shallower groundwater tables were significantly taller and had greater canopy volumes. A key finding was that pink gums occurring on deep sands with moderate mean annual rainfall for the study region and with high mistletoe loads, had low canopy intactness. Areas of future research should focus on: which populations of pink gums are at least partially groundwater dependent; the interaction between pink gum water stress and mistletoe abundance over long time frames; and differences between pink gum provenances in drought response and growth rates. Future monitoring of survey sites established in this study would provide information on pink gum canopy and population trends, and mistletoe population trends.Thesis (Ph.D.) -- University of Adelaide, School of Biological Sciences, 2017.
Libri sul tema "Canopy decline"
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Plotz, Judith A. Ideas of the decline of poetry: A study in English criticism from 1700 to 1830. New York: Garland Pub., 1987.
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Annulment, the wedding that was: How the church can declare a marriage null. New York: Paulist Press, 1999.
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Szewczyk, Janusz. Rola zaburzeń w kształtowaniu struktury i dynamiki naturalnych lasów bukowo-jodłowo-świerkowych w Karpatach Zachodnich. Publishing House of the University of Agriculture in Krakow, 2018. http://dx.doi.org/10.15576/978-83-66602-35-9.
Testo completoAbstract (sommario):
The aim of the study was to determine the influence of different disturbances (both natural and anthropogenic) on species composition and stand structure of old-growth mixed mountain forests in the Western Carpathians. These stands are usually dominated by beech, fir and spruce, mixed in different proportions. The tree main species represent different growth strategies, and they compete against each other. The longevity of trees makes the factors influencing the stand structure difficult to identify, even during longitudinal studies conducted on permanent research plots. That is why dendroecological techniques, based upon the annual variability of tree rings, are commonly used to analyze the disturbance histories of old-growth stands. Dendroecological methods make it possible to reconstruct the stand history over several centuries in the past by analyzing the frequency, intensity, duration and spatial scale of disturbances causing the death of trees. Combining the dendroecological techniques with the detailed measurements of stand structure, snag volume, CWD volume, and the analyses of regeneration species composition and structure allows us to identify the factors responsible for the changes in dynamics of mixed mountain forests. Various disturbance agents affect some species selectively, while some disturbances promote the establishment of tree seedlings of specific species by modifying environmental conditions. Describing the disturbance regime requires a broad scope of data on stand structure, on dead wood and tree regeneration, while various factors affecting all the stages of tree growth should be taken into consideration. On the basis of the already published data from permanent sample plots, combined with the available disturbance history analyses from the Western Carpathians, three research hypotheses were formulated. 1. The species composition of mixed mountain forests has been changing for at least several decades. These directional changes are the consequence of simultaneous conifer species decline and expansion of beech. 2. The observed changes in species composition of mixed mountain forests are the effect of indirect anthropogenic influences, significantly changing tree growth conditions also in the forests that are usually considered natural or near-natural. Cumulative impact of these indirect influences leads to the decrease of fir share in the tree layer (spruce decline has also been observed recently),and it limits the representation of this species among seedlings and saplings. The final effect is the decrease of fir and spruce share in the forest stands. 3. Small disturbances, killing single trees or small groups of trees, and infrequent disturbances of medium size and intensity dominate the disturbance regime in mixed mountain forests. The present structure of beech-fir-spruce forests is shaped both by complex disturbance regime and indirect anthropogenic influences. The data were gathered in permanent sample plots in strictly protected areas of Babia Góra, Gorce, and Tatra National Parks, situated in the Western Carpathians. All plots were located in the old-growth forest stands representing Carpathian beech forest community. The results of the measurements of trees, snags, coarse woody debris (CWD) and tree regeneration were used for detailed description of changes in the species composition and structure of tree stands. Tree ring widths derived from increment cores were used to reconstruct the historical changes in tree growth trends of all main tree species, as well as the stand disturbance history within the past two to three hundred years. The analyses revealed complex disturbance history in all of the three forest stands. Intermediate disturbances of variable intensity occurred, frequently separated by the periods of low tree mortality lasting from several decades up to over one hundred years. The intervals between the disturbances were significantly shorter than the expected length of forest developmental cycle, in commonly used theories describing the dynamics of old-growth stands. During intermediate disturbances up to several dozen percent of canopy trees were killed. There were no signs of stand-replacing disturbances, killing all or nearly all of canopy trees. The periods of intense tree mortality were followed by subsequent periods of increased sapling recruitment. Variability in disturbance intensity is one of the mechanisms promoting the coexistence of beech and conifer species in mixed forests. The recruitment of conifer saplings depended on the presence of larger gaps, resulting from intermediate disturbances, while beech was more successful in the periods of low mortality. However, in the last few decades, beech seems to benefit from the period of intense fir mortality. This change results from the influence of long-term anthropogenic disturbances, affecting natural mechanisms that maintain the coexistence of different tree species and change natural disturbance regimes. Indirect anthropogenic influence on tree growth was clearly visible in the gradual decrease of fir increments in the twentieth century, resulting from the high level of air pollution in Europe. Synchronous decreases of fir tree rings’ widths were observed in all three of the sample plots, but the final outcomes depended on the fir age. In most cases, the damage to the foliage limited the competitive abilities of fir, but it did not cause a widespread increase in tree mortality, except for the oldest firs in the BGNP (Babia Góra National Park) plot. BGNP is located in the proximity of industrial agglomeration of Upper Silesia, and it could be exposed to higher level of air pollution than the other two plots. High level of fir regeneration browsing due to the deer overabundance and insufficient number of predators is the second clear indication of the indirect anthropogenic influence on mixed mountain forests. Game impact on fir regeneration is the most pronounced in Babia Góra forests, where fir was almost completely eliminated from the saplings. Deer browsing seems to be the main factor responsible for limiting the number of fir saplings and young fir trees, while the representation of fir among seedlings is high. The experiments conducted in fenced plots located in the mixed forests in BGNP proved that fir and sycamore were the most preferred by deer species among seedlings and saplings. In GNP (Gorce National Park) and TNP (Tatra National Park), the changes in species composition of tree regeneration are similar, but single firs or even small groups of firs are present among saplings. It seems that all of the analysed mixed beech-fir-spruce forests undergo directional changes, causing a systematic decrease in fir representation, and the expansion of beech. This tendency results from the indirect anthropogenic impact, past and present. Fir regeneration decline, alongside with the high level of spruce trees’ mortality in recent years, may lead to a significant decrease in conifers representation in the near future, and to the expansion of beech forests at the cost of mixed ones.
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Rosario, Vanessa Pérez. Multiple Legacies. University of Illinois Press, 2017. http://dx.doi.org/10.5406/illinois/9780252038969.003.0005.
Testo completoAbstract (sommario):
This chapter studies the work of Puerto Rican, Dominican, and Cuban writers in the diaspora who inherited and extended Burgos's legacy in the contemporary public imaginary. Her legacy among queer, feminist, and diaspora writers highlights the challenge to the Puerto Rican literary canon, the cult of patriarchy, and the foundational myth of la gran familia in Puerto Rican literature, which began to decline in the 1970s. For groups traditionally omitted from the national imaginary, claiming Burgos offered a way to tap into the island's nationalistic impulses, shared history, and social memory. Moreover, in a cosmopolitan city such as New York, Burgos became a transnational Latina/o cultural icon. Reinventing, reimagining, and riffing off Burgos becomes a way for artists to voice their struggles for recognition and self-determination in New York, echoing the themes developed in her writing.
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Öyken, Ekin, e Çiğdem Dürüsken. Reviving Virgil in Turkish. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198810810.003.0013.
Testo completoAbstract (sommario):
The Turkish reception of Virgil has a colourful history that started mainly during the decline of the multi-ethnic Ottoman Empire in the late nineteenth century. This may seem typical of Virgil’s initial reception by a culture, usually European, that relates primarily to his perceived idealism. However, closer study of this first period alone, which relies largely on French scholarship, reveals that factors other than cultural politics are at play. Right after the 1897 politico-literary ‘classics debate’ over the need for a literary canon for the new Turkish culture and its most suitable source, Öyken and Dürüşken observe a focus on Virgil’s poetics rather than on the political value of his work. Similarly, the first complete translation of Virgil (through an intermediary translation in French), published in 1929 as one of the first books in the newly adopted Latin alphabet, represents the beginning of a new era in more than one sense.
Capitoli di libri sul tema "Canopy decline"
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Marsh, David. "Poggio and Alberti Revisited". In Atti, 89–102. Florence: Firenze University Press, 2020. http://dx.doi.org/10.36253/978-88-6453-968-3.08.
Testo completoAbstract (sommario):
The careers of the Curial secretaries Poggio Bracciolini (1380-1459) and Leon Battista Alberti (1404-1472) reveal many parallels. In 1437-1438 the Este court of Ferrara, where Eugenius IV convoked a church council, provided a focal point for their friendship. It was to the Ferrarese canon Francesco Marescalchi that Poggio dedicated Book 1 of his Latin epistles (1436), and Alberti his Hundred Apologues (1437). Both men were inspired to critiques of contemporary society by the Greek satirist Lucian, and both indulged in composing brief witticisms that expose human vice: Poggio in his Facetiae (Jests) and Alberti in his Apologi (Fables) and Vita (Autobiography). From Lucian, they also learned to dramatize human foibles on the imagined stage of the theatrum mundi, or theater of the world: Poggio in his dialogues, and Alberti in both the Intercenales and Momus. Despite such literary affinities, their approach to ethical questions differed, especially concerning the validity of allegory, which Poggio rejected but Alberti embraced. As a tribute to his colleague, Alberti dedicated Book 4 of his Intercenales to Poggio; he prefaced the work with an ironic Aesopic fable that asserts the superiority of recondite scientific research over commonplace humanistic studies. Eventually, Alberti’s status as an outsider in Florence was reflected in the deterioration in his relations with Poggio. The rift was widened in 1441, when Alberti organized the Italian poetic competition called the Certame Coronario that was held in the Florence cathedral on October 22. Poggio was a member of the jury that, to Alberti’s chagrin, refused to declare a winner.
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Luo, Qinghong, Qimin Chen, Miao He e Na Li. "Characteristic on the Stability of Haloxylon Ammodendron Plantation in the Southern Fringe of Gurbantunggut Desert, Northwest China". In Deserts and Desertification [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.99050.
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Using chronosequence theory and method, the characteristics of vegetation-soil coupling and structure stability of Haloxylon ammodendron plantations in the southern fringe of Gurbantunggut Desert were analyzed. The results showed, the canopy storey of H. ammodendron plantation experienced three stages, rapid growth (the age of 7 to 20), then slow growth (the age of 20 to 28) and last decline (over the age of 28). The best natural regeneration started from 17-yr-old plantation. Vegetation-soil system coupling degree (C) and coupling coordinative degree (D) of plantations with different age were not one-to-one correspondence. The system of H. ammodendron plantations always stayed in disorder recession, vegetation and soil were prone to loss type during the process of sand-fixation. Five principal components evaluated that the first rank was 42-yr-old plantation. It was inferred that the trend of the vegetation and soil system was from senescence to harmonious development. So the trend of coordinated development between vegetation and soil would be promoted, if the artificial tending and management measures strengthened.
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"Libraries and Canon: Ascent and Decline of the Greek Torah". In Libraries, Translations, and 'Canonic' Texts, 26–99. BRILL, 2006. http://dx.doi.org/10.1163/9789047409014_004.
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Murphet, Julian, e Julian Murphet. "The Law of Diminishing Returns". In Todd Solondz, 1–137. University of Illinois Press, 2019. http://dx.doi.org/10.5622/illinois/9780252042768.003.0001.
Testo completoAbstract (sommario):
This chapter tracks Todd Solondz's canny cinematic homeopathy with the nation's overarching economic decline under several rubrics. The first is the built environment of his films, interested as they are in the aesthetically valueless architecture of “junkspace.” Next, the chapter examines his stylistic posture of “left classicism,” which borrows key aesthetic principles from the dominant industry, only to drain them of their usual affirmative functions. His several ontological gestures of “eternal recurrence,” offered with the twist of a general decline in standards, are then explored. Afterward, the chapter discusses his determined interest in the dynamic opposition between playful sequences of fantasy and escape and unendurable long takes of truly intolerable material. Finally, his thematic preoccupation with the excremental function of the “gift of shit,” which he analyzes in an exhaustive fashion, is studied.
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Cairns, John W. "Ius Civile in Scotland, c 1600". In Law, Lawyers, and Humanism. Edinburgh University Press, 2015. http://dx.doi.org/10.3366/edinburgh/9780748682096.003.0003.
Testo completoAbstract (sommario):
This chapter analyzes the changing nature of the references to sources in Scotland in the 100 years or so after the founding of the College of Justice. It traces a decline in the overt reliance on Canon law through examination of the sources cited in the Jus feudale of Thomas Craig, written around 1600, and the Practicks of Sir Robert Spottiswoode, collected from the 1620s to the 1640s. It shows the continued significance of Canon law, but a failure to cite it by Spottiswoode, other than in his reliance on it for procedural issues. While Sinclair’s Practicks demonstrate that Scotland had a typical mix of ius commune (Canon and Civil laws) and ius proprium (Scots customs and statutes), Craig and Spottiswoode’s works suggest that in the intervening period there had been a subtle change out of which emerged a competing understanding of the nature of Scots law, located within the structure of the law of nature and nations in a Europe of developing nation states with imperial ambitions.
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Avni, Gideon. "Between Hazor and Masada". In Testing the Canon of Ancient Near Eastern Art and Archaeology, 302–4. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190673161.003.0015.
Testo completoAbstract (sommario):
This chapter explains the link between remains from “biblical” and classical times and modern Israel as a significant theme in constructing local identities. Excavations of sites of the Bronze and Iron Ages yielded new monuments and artifacts that were occasionally used for the creation of a new collective memory for modern Israelis, and the epic excavations at Masada conducted by Yigael Yadin in the 1960s became a significant landmark in the creation of a collective memory linking modern Israel to its past. However, the late twentieth and early twenty-first centuries evinced profound changes in the attitude of Israelis toward archaeology. A constant decline in the status of archaeology as a national emblem has occurred as part of major changes in Israeli society.
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Mayer, Peta. "The Degenerate in Falling Slowly (1998)". In Misreading Anita Brookner, 192–223. Liverpool University Press, 2020. http://dx.doi.org/10.3828/liverpool/9781789620597.003.0006.
Testo completoAbstract (sommario):
Silence and rereading are key discursive practices of Miriam and Beatrice Sharpe, the sister protagonists of Falling Slowly. Their forms of absence and excess cause critics to herald the decline of Brookner’s powers in her early reception.The sisters also share a number of behaviours with the aesthetes and Decadents labelled degenerate in Max Nordau’s Degeneration including Joris-Karl Huysmans, Baudelaire and Stéphane Mallarmé. Such behaviours include dullness, decline, ennui, inactivity, boredom, invisibility, anxiety, restlessness and absence. This chapter spins the hierarchical figure of the degenerate across the sister relationship of the domestic fiction to produce a queering of the domestic fiction. Rejecting the normative impulse of the figure, it instead engages its deconstructive capacity to render transparent the mechanisms of epistemological production and expose the way in which subjects and objects attain status as real or unreal, healthy or sick, visible or invisible, literal or figurative, heterosexual or lesbian. Inspired by Lee Edelman’s No Future: Queer Theory and the Death Drive, it mobilises a ‘no future’ narrative as the narrative form of the degenerate. The rhetorical form of syllepsis, which governs shifts between the literal and figurative, is reappropriated from the male canon to underscore the open-ended nature of signification.
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Gould, Rebecca Ruth. "The Sovereign and the Poet’s Body". In The Persian Prison Poem, 207–50. Edinburgh University Press, 2021. http://dx.doi.org/10.3366/edinburgh/9781474484015.003.0007.
Testo completoAbstract (sommario):
This chapter focuses on medieval Persian political theology. In celebrating poetry’s sovereignty, the prison poem shifted the authority that used to be attached to the ruler’s body to the poet, a process facilitated by the decline of caliphal power. Stimulated by a new perception of the fragility and contingency of worldly power, this genre introduced a new political aesthetic into the twelfth-century eastern Islamic world. The prison poem genre’s discursive dimension is further manifested in its use of discourses of governance to assert the poet’s spiritual authority. Alongside its readings of political theory, this chapter also engages with the literary-theoretical texts that shaped the canon of classical Persian poetics and which framed the emergence of the prison poem.
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Stow, Kenneth. "The Roman Ghetto". In Anna and Tranquillo. Yale University Press, 2016. http://dx.doi.org/10.12987/yale/9780300219043.003.0004.
Testo completoAbstract (sommario):
This chapter analyzes the Roman Jewry's political condition—the scene of the drama, its setting, and its background—and draws a picture of the core of Roman Jewish life: the Roman Ghetto. By the eighteenth century, the ghetto had become a wretched place. What had set the decline in motion were policies begun in 1555 by Pope Paul IV and continued by his successors, often with greater rigor. Over hundreds of years, there was an incremental hardening of limitations on Jews that the canon law of the Church had established as early as the eighth and ninth centuries. The bull Cum nimis absurdum set policy not only for Rome, but also for all places under direct papal rule, which meant most of central Italy. It also put pressure on adjacent principalities to follow suit.
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Kirsch, Stuart. "How Analysis of Local Contexts Can Have Global Significance". In Engaged Anthropology. University of California Press, 2018. http://dx.doi.org/10.1525/california/9780520297944.003.0006.
Testo completoAbstract (sommario):
This chapter considers claims about culture loss at hearings of the Nuclear Claims Tribunal in the Marshall Islands, including the impact of nuclear weapons testing on the people of Rongelap Atoll. The concept of cultural property is used to identify the referents of discourse about culture loss, including local knowledge, subsistence production, and connections to place. For example, the absence of breadfruit and pandanus trees on the atolls where the people from Rongelap were relocated prevented them from teaching subsequent generations how to build their distinctive sailing canoes, contributing to the decline of long-distance voyaging and the loss of knowledge about navigation by the stars and wave patterns. These discussions have been taken up by international debates about noneconomic loss and damage resulting from climate change, a matter of considerable significance for the people living in the Marshall Islands, given their double exposure to both nuclear radiation and rising sea levels.
Atti di convegni sul tema "Canopy decline"
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Benge, Margaret, Yunxing Lu, Allan Katende, Jonny Rutqvist, Dustin Crandall, Adam Haecker, George King, Joseph B. Renk, Mileva Radonjic e Andrew Bunger. "Connecting Geomechanical Properties with Potential for Proppant Embedment and Production Decline for the Emerging Caney Shale, Oklahoma". In Unconventional Resources Technology Conference. Tulsa, OK, USA: American Association of Petroleum Geologists, 2021. http://dx.doi.org/10.15530/urtec-2021-5084.
Testo completo
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Kolmer, Haden P., Clark M. Cunningham e Mohammed F. Al-Dushaishi. "ROP Optimization of Lateral Wells in SW Oklahoma: Artificial Neural Network Approach". In ASME 2022 Onshore Petroleum Technology Conference. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/optc2022-91464.
Testo completoAbstract (sommario):
Abstract Rate of Penetration (ROP) optimization has played a key role in the economic return and value of both onshore and offshore wells by decreasing drilling time thereby increasing the net present value (NPV) of the localized field. In this study, an Artificial Neural Network (ANN) model is developed to accurately model the ROP of a well in SW Oklahoma to optimize the drilling process. A parametric study was conducted to showcase the effect of operational parameters on the ROP-ANN model and to minimize error and increase accuracy. The number of neurons and hidden layers within the model are optimized based on the lowest Mean Square Error (MSE) and highest R2. A comparative study was comprised of one well in Southern Oklahoma targeting the Caney Shale. The well is about 10,000″ vertical with a 2-mile lateral with a maximum inclination of 78° and Dogleg Severity (DLS) of 12°/100ft. UCS was incorporated into the model to geomechanically differentiate between shale, sandstone, and limestone. The input drilling data is weighed against ROP showcasing the impact of each parameter on ROP. From this and further proven in the results, RPM, WOB, and UCS greatly effect ROP per foot based on the sensitivity analysis but steadily decline as the critical value is achieved. The major advantage of this study is developing an accurate ANN model for onshore North American shale plays in understanding the lithological impact of UCS and high lateral deviation on ROP which can be used in pre-planning to optimize the drilling processes.
Rapporti di organizzazioni sul tema "Canopy decline"
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Leis, Sherry. Vegetation community monitoring trends in restored tallgrass prairie at Wilson’s Creek National Battlefield: 2008–2020. National Park Service, aprile 2022. http://dx.doi.org/10.36967/nrr-2293117.
Testo completoAbstract (sommario):
Plant community monitoring at Wilson’s Creek National Battlefield (NB) focused on the restored tallgrass prairie community. Six monitoring sites were visited four times and observations of plant species and ground cover were made. In addition to those observations, we included two environmental factors in this report—precipitation and recent fire history—to help understand the vegetation data status and trends. Precipitation data (standardized vegetation index) indicated drought conditions in 2012 and some dry periods in 2016. Although prairies are adapted to drought, we found that species richness at the site and community scales (alpha and gamma diversity) were reduced in dry years. Fire management also plays an important role in shaping the plant communities. Prescribed fire occurrence became less frequent through the monitoring period. Also, additional treatments, including herbicide and mowing, likely shaped the prairie community. Tree regeneration and nonnative plants in particular may have been affected by these techniques. The prairie plant community continues to be moderately diverse despite recent increases in tree seedlings and small saplings. Species richness varied over time and was correlated with precipitation; diversity indices (H′ and J′) were similar across monitored years. Species guilds (also known as functional groups) demonstrated differing patterns. Woody plants, long a concern at the park, were abundant and statistically similar across years. Many guilds were quite variable across the sites, but nonnative forbs declined, and nonnative grasses increased. Overstory trees and canopy cover, measured for the first time in 2020, have likely influenced the composition of one site. The composition of this site points to a shrubland-savanna community. Four of the sites tended towards shrubland rather than tallgrass prairie. The vegetation monitoring protocol experienced some changes between 2008 and 2020. A key difference was a shift from sampling twice during the field season to sampling only once in a monitoring year. An anticipated decline in species richness was observed in 2012 and 2016, but we were unable to isolate sample design as the cause. Additionally, we remedied inconsistencies in how tree regeneration was recorded by tallying seedlings and saplings in the field. Our quality assurance procedures indicated that our observer error from pseudoturnover was 20.2%, meeting our expectations. Cover class estimates agreed 73% of the time, with all disagreements within one cover class. Coordinating management actions to achieve plant community goals like structure and composition of tallgrass prairie will be critical to the survival of the prairie species at the park. Fire and nonnative plant treatments along with the reduction of woody cover including trees are needed to arrest the transition to savanna and woodland community types. Frequent prescribed fire is an integral process for this community and there is no equivalent substitute. Continued focus on management for the desired tallgrass prairie community will also provide needed habitat for imperiled pollinators such as the monarch butterfly. Best management practices for pollinators on federal lands specify that treatments (prescribed fire, mowing or haying) should not occur during the blooming season or when pollinator breeding, egg, larval or pupal stages are present.
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Boyle, Maxwell, e Elizabeth Rico. Terrestrial vegetation monitoring at Fort Pulaski National Monument: 2019 data summary. National Park Service, dicembre 2021. http://dx.doi.org/10.36967/nrds-2288716.
Testo completoAbstract (sommario):
The Southeast Coast Network (SECN) conducts long-term terrestrial vegetation monitoring as part of the nationwide Inventory and Monitoring Program of the National Park Service (NPS). The vegetation community vital sign is one of the primary-tier resources identified by SECN park managers, and monitoring is currently conducted at 15 network parks (DeVivo et al. 2008). Monitoring plants and their associated communities over time allows for targeted understanding of ecosystems within the SECN geography, which provides managers information about the degree of change within their parks’ natural vegetation. 2019 marks the first year of conducting this monitoring effort on four SECN parks, including Fort Pulaski National Monument (FOPU). Twelve vegetation plots were established at Fort Pulaski National Monument in August. Data collected in each plot included species richness across multiple spatial scales, species-specific cover and constancy, species-specific woody stem seedling/sapling counts and adult tree (greater than 10 centimeters [3.9 inches {in}]) diameter at breast height (DBH), overall tree health, landform, soil, observed disturbance, and woody biomass (i.e., fuel load) estimates. This report summarizes the baseline (year 1) terrestrial vegetation data collected at Fort Pulaski National Monument in 2019. Data were stratified across two dominant broadly defined habitats within the park (Maritime Tidal Wetlands and Maritime Upland Forests and Shrublands). Noteworthy findings include: Sixty-six vascular plant taxa were observed across 12 vegetation plots, including six taxa not previously known from the park. Plots were located on both Cockspur and McQueen’s Island. The most frequently encountered species in each broadly defined habitat included: Maritime Tidal Wetlands: smooth cordgrass (Spartina alterniflora), perennial saltmarsh aster(Symphyotrichum enuifolium), and groundsel tree (Baccharis halimifolia) Maritime Upland Forests and Shrublands: yaupon (Ilex vomitoria), southern/eastern red cedar (Juniperus silicicola + virginiana), and cabbage palmetto (Sabal palmetto). Four non-native species identified as invasive by the Georgia Exotic Pest Plant Council (GA-EPPC 2018) were found during this monitoring effort. These species (and their overall frequency of occurrence within all plots) included: Japanese honeysuckle (Lonicera japonica; 17%), bahiagrass (Paspalum notatum; 8%), Vasey’s grass (Paspalum urvillei; 8%), and European common reed (Phragmites australis; 8%). Two rare plants tracked by the Georgia Department of Natural Resources (GADNR 2013) were found during this monitoring effort. These include Florida wild privet (Forestiera segregata) and Bosc’s bluet (Oldenlandia boscii). Southern/eastern red cedar and cabbage palmetto were the most dominant species within the tree stratum of the maritime Upland Forest and Shrubland habitat type. Species that dominated the sapling and seedling strata of this type included yaupon, cabbage palmetto, groundsel tree, and Carolina laurel cherry (Prunus caroliniana). The health status of sugarberry (Celtis laevigata)—a typical canopy species in maritime forests of the South Atlantic Coastal Plain--observed on park plots appeared to be in decline, with most stems experiencing elevated levels of dieback and low vigor. Over the past decade, this species has been experiencing unexplained high rates of dieback and mortality throughout its range in the Southeastern United States; current research is focusing on what may be causing these alarming die-off patterns. Duff and litter made up the majority of downed woody biomass (fuel loads) across FOPU vegetation plots.
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DeSaix, Matthew. Bird community monitoring at New River Gorge National River, Gauley River National Recreation Area, and Bluestone National Scenic River, 1997 - 2018. National Park Service, gennaio 2022. http://dx.doi.org/10.36967/nrr-2289846.
Testo completoAbstract (sommario):
Birds are prominent features of National Park Service lands and are effective indicators for monitoring ecosystem health. Assessing the temporal change of avian species abundance depends on long-term monitoring of bird communities and trends, however long-term monitoring programs are generally uncommon. In this report, we summarize 22 years (1997-2018) of point count data across five sites on West Virginia National Park Service lands (three in New River Gorge National River, one in Gauley River National Recreation Area, and one in Bluestone National Scenic River) and compare these results to our analysis of Breeding Bird Survey data for the same time period across all of West Virginia. The objectives of this analysis are two-fold: 1) describe the biotic integrity of the National Park Service lands in West Virginia and 2) Quantify trends in guilds and species abundance. During the 20-year period of this survey, 85 breeding resident species were detected. The West Virginia National Park Service lands are home to stable populations of Wood Thrush and Yellow-billed Cuckoo, both species of continental concern by Partners in Flight. Seven species have declined precipitously on NPS lands during this time period. Three of these species are also experiencing declines across the rest of West Virginia (Blue-gray Gnatcatcher, Carolina Chickadee, Kentucky Warbler), but the other 4 species are stable across West Virginia (Acadian Flycatcher, Black-throated Green Warbler, Northern Parula, Swainson’s Warbler). Four species that are declining across West Virginia (Great Crested Flycatcher, Indigo Bunting, Red-eyed Vireo, and Worm-eating Warbler) are stable on southern West Virginia NPS lands. Additionally, the upper-canopy foraging guild of species has decreased significantly on NPS lands in southern West Virginia. An analysis of community biotic integrity revealed that the southern West Virginia NPS lands have been stable at a rating of high biotic integrity every year for the duration of this survey. Future research should delve into the underlying factors that may be driving the trends in abundance at different scales.
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Weissinger, Rebecca, e Dana Witwicki. Riparian monitoring of wadeable streams at Courthouse Wash, Arches National Park: Summary report, 2010–2019. A cura di Alice Wondrak Biel. National Park Service, novembre 2021. http://dx.doi.org/10.36967/nrr-2287907.
Testo completoAbstract (sommario):
The goal of Northern Colorado Plateau Network (NCPN) riparian monitoring is to determine long-term trends in hydrologic, geomorphic, and vegetative properties of wadeable streams in the context of changes in other ecological drivers, stressors, and processes. This information is intended to provide early warning of resource degradation and determine natural variability of wadeable streams. This report summarizes NCPN monitoring of Courthouse Wash in Arches National Park (NP) from 2010 to 2019. The focus of this report is to (1) present geomorphology and vegetation data from five reaches monitored in Courthouse Wash from 2010 to 2015, and (2) examine patterns in water availability at one monitoring reach from November 2010 to December 2019. Vegetation sampling and geomorphology surveys were suspended in 2016 due to budget cuts; this report presents baseline data for future comparisons. The NCPN has five monitoring reaches located between the inflow of Sevenmile Canyon, a major tributary, and the terminus of Courthouse Wash, at the Colorado River. Two reaches (2, 5) are located in Upper Courthouse Wash, and three (1, 4, 7) in Lower Courthouse Wash. Hydrologic monitoring wells are installed only at Reach 1. During our monitoring period, which included drought years in 2012 and 2018 and a wetter-than-average period from fall 2013 to 2014, groundwater levels showed steep declines corresponding to the start of the growing season each year. Hot, dry summers and falls in 2012, 2018, and 2019 showed the deepest troughs in groundwater levels. Active monsoon years helped elevate summer and fall groundwater levels in 2013 and 2014. Continued monitoring will help us better understand the relationship of climate and water availability at this reach. A geomorphic survey was completed once for reaches 2, 4, and 7, and twice for reaches 5 and 1. Powerful floods during our monitoring period resulted in aggradation of the channel in reaches 5 and 1, which were first surveyed in March 2013. Flooding in September 2013 resulted in an average of 0.24 meters of deposition found in the channel thalweg at Reach 1 in March 2014. Storm events in May 2014 caused additional aggradation. In March 2015, an average of 0.41 meters of deposition was recorded in the channel thalweg at Reach 5, with 0.32 meters of deposition between the vegetation transect headpins compared to the 2013 data. The riparian vegetation recorded at our monitoring reaches is consistent with an open-canopy Fremont cottonwood woodland with a diverse understory. Canopy closure ranged from 29% to 52%. Measurements were sensitive enough to detect a 10% reduction in canopy closure at Reach 5 during a pest infestation in June 2013. Canopy closure subsequently rebounded at the reach by 2015. Total obligate and facultative wetland cover ranged from 7% to 26%. Fremont cottonwood seedlings, saplings, and overstory trees were present at all reaches, indicating good potential for future regeneration of the canopy structure. These data can serve as a baseline for comparison with future monitoring efforts. One area of management concern is that exotic-plant frequency and cover were relatively high in all monitoring reaches. Exotic cover ranged from 2% to 30%. High exotic cover was related to years with high cover of annual brome grasses. High cover of exotic grasses is associated with increased wildfire risk in southwestern riparian systems, which are not well-adapted to fire. Managers should be prepared for this increased risk following wet winters that promote annual brome grass cover. Beaver activity was noted throughout bedrock-constrained reaches in Courthouse Wash. Beaver activity can reduce adjacent woody riparian vegetation cover, but it also contributes to maintaining a higher water table and persistent surface water. Climate change is likely to be an increasingly significant stressor in Courthouse Wash, as hotter, drier conditions decrease water levels and increase drought stress...
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Barg, Rivka, Erich Grotewold e Yechiam Salts. Regulation of Tomato Fruit Development by Interacting MYB Proteins. United States Department of Agriculture, gennaio 2012. http://dx.doi.org/10.32747/2012.7592647.bard.
Testo completoAbstract (sommario):
Background to the topic: Early tomato fruit development is executed via extensive cell divisions followed by cell expansion concomitantly with endoreduplication. The signals involved in activating the different modes of growth during fruit development are still inadequately understood. Addressing this developmental process, we identified SlFSM1 as a gene expressed specifically during the cell-division dependent stages of fruit development. SlFSM1 is the founder of a class of small plant specific proteins containing a divergent SANT/MYB domain (Barg et al 2005). Before initiating this project, we found that low ectopic over-expression (OEX) of SlFSM1 leads to a significant decrease in the final size of the cells in mature leaves and fruits, and the outer pericarp is substantially narrower, suggesting a role in determining cell size and shape. We also found the interacting partners of the Arabidopsis homologs of FSM1 (two, belonging to the same family), and cloned their tomato single homolog, which we named SlFSB1 (Fruit SANT/MYB–Binding1). SlFSB1 is a novel plant specific single MYB-like protein, which function was unknown. The present project aimed at elucidating the function and mode of action of these two single MYB proteins in regulating tomato fruit development. The specific objectives were: 1. Functional analysis of SlFSM1 and its interacting protein SlFSB1 in relation to fruit development. 2. Identification of the SlFSM1 and/or SlFSB1 cellular targets. The plan of work included: 1) Detailed phenotypic, histological and cellular analyses of plants ectopically expressing FSM1, and plants either ectopically over-expressing or silenced for FSB1. 2) Extensive SELEX analysis, which did not reveal any specific DNA target of SlFSM1 binding, hence the originally offered ChIP analysis was omitted. 3) Genome-wide transcriptional impact of gain- and loss- of SlFSM1 and SlFSB1 function by Affymetrix microarray analyses. This part is still in progress and therefore results are not reported, 4) Search for additional candidate partners of SlFSB1 revealed SlMYBI to be an alternative partner of FSB1, and 5) Study of the physical basis of the interaction between SlFSM1 and SlFSB1 and between FSB1 and MYBI. Major conclusions, solutions, achievements: We established that FSM1 negatively affects cell expansion, particularly of those cells with the highest potential to expand, such as the ones residing inner to the vascular bundles in the fruit pericarp. On the other hand, FSB1 which is expressed throughout fruit development acts as a positive regulator of cell expansion. It was also established that besides interacting with FSM1, FSB1 interacts also with the transcription factor MYBI, and that the formation of the FSB1-MYBI complex is competed by FSM1, which recognizes in FSB1 the same region as MYBI does. Based on these findings a model was developed explaining the role of this novel network of the three different MYB containing proteins FSM1/FSB1/MYBI in the control of tomato cell expansion, particularly during fruit development. In short, during early stages of fruit development (Phase II), the formation of the FSM1-FSB1 complex serves to restrict the expansion of the cells with the greatest expansion potential, those non-dividing cells residing in the inner mesocarp layers of the pericarp. Alternatively, during growth phase III, after transcription of FSM1 sharply declines, FSB1, possibly through complexing with the transcription factor MYBI serves as a positive regulator of the differential cell expansion which drives fruit enlargement during this phase. Additionally, a novel mechanism was revealed by which competing MYB-MYB interactions could participate in the control of gene expression. Implications, both scientific and agricultural: The demonstrated role of the FSM1/FSB1/MYBI complex in controlling differential cell growth in the developing tomato fruit highlights potential exploitations of these genes for improving fruit quality characteristics. Modulation of expression of these genes or their paralogs in other organs could serve to modify leaf and canopy architecture in various crops.