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1
Plotkin, Howard. "Henry A. Ward and the Recovery of the Santa Rosa, Colombia, Meteorite." Earth Sciences History 24, no. 1 (January 1, 2005): 63–80. http://dx.doi.org/10.17704/eshi.24.1.e6j21052q8245023.
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Henry A. Ward (1834-1906), the celebrated founder and owner of Ward's Natural Science Establishment, one of the most interesting and significant North American scientific institutions in the late 19th century, was also perhaps the shrewdest and most enthusiastic meteorite collector of his day. Toward the end of his career, at age 68, he became very interested in a large (612.5 kg) iron meteorite in Santa Rosa, Colombia that was highly venerated by the local townspeople. In an effort to obtain the meteorite in whole or in part—and hopefully clear up the scientific confusion surrounding it—he journeyed to Santa Rosa in the winter of 1906. His attempt to retrieve the meteorite led to a clever plan with local officials, a daring nighttime removal, and a heated legal battle with the national police, but eventually he was allowed to leave Colombia with a large piece of the meteorite. His subsequent investigation of the meteorite is examined, as is our present understanding of it and its relationship to two meteorites found nearby, Rasgatá and Tocavita. Ward's actions shed light on attitudes and practices in natural history collecting at his time, and how scientists grappled with the problem of interpreting meteoritic structure.
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Blackwood, Christopher B., Terry Marsh, Sang-Hoon Kim, and Eldor A. Paul. "Terminal Restriction Fragment Length Polymorphism Data Analysis for Quantitative Comparison of Microbial Communities." Applied and Environmental Microbiology 69, no. 2 (February 2003): 926–32. http://dx.doi.org/10.1128/aem.69.2.926-932.2003.
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ABSTRACT Terminal restriction fragment length polymorphism (T-RFLP) is a culture-independent method of obtaining a genetic fingerprint of the composition of a microbial community. Comparisons of the utility of different methods of (i) including peaks, (ii) computing the difference (or distance) between profiles, and (iii) performing statistical analysis were made by using replicated profiles of eubacterial communities. These samples included soil collected from three regions of the United States, soil fractions derived from three agronomic field treatments, soil samples taken from within one meter of each other in an alfalfa field, and replicate laboratory bioreactors. Cluster analysis by Ward's method and by the unweighted-pair group method using arithmetic averages (UPGMA) were compared. Ward's method was more effective at differentiating major groups within sets of profiles; UPGMA had a slightly reduced error rate in clustering of replicate profiles and was more sensitive to outliers. Most replicate profiles were clustered together when relative peak height or Hellinger-transformed peak height was used, in contrast to raw peak height. Redundancy analysis was more effective than cluster analysis at detecting differences between similar samples. Redundancy analysis using Hellinger distance was more sensitive than that using Euclidean distance between relative peak height profiles. Analysis of Jaccard distance between profiles, which considers only the presence or absence of a terminal restriction fragment, was the most sensitive in redundancy analysis, and was equally sensitive in cluster analysis, if all profiles had cumulative peak heights greater than 10,000 fluorescence units. It is concluded that T-RFLP is a sensitive method of differentiating between microbial communities when the optimal statistical method is used for the situation at hand. It is recommended that hypothesis testing be performed by redundancy analysis of Hellinger-transformed data and that exploratory data analysis be performed by cluster analysis using Ward's method to find natural groups or by UPGMA to identify potential outliers. Analyses can also be based on Jaccard distance if all profiles have cumulative peak heights greater than 10,000 fluorescence units.
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Reader, R. J., and J. Buck. "Control of seedling density on disturbed ground: role of seedling establishment for some midsuccessional, old-field species." Canadian Journal of Botany 69, no. 4 (April 1, 1991): 773–77. http://dx.doi.org/10.1139/b91-100.
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In midsuccessional old fields, seedlings are often concentrated in patches of disturbed ground, such as earth mounds created by burrowing mammals. An experiment was conducted to determine whether interspecific variation in seedling density on mounds reflected interspecific variation in potential seedling establishment (i.e., the number of seedlings established per 1000 seeds sown). Seeds of 13 old-field forbs were sown on experimentally created mounds in an abandoned pasture. Their potential seedling establishment ranged from 0 to 156 seedlings per 1000 seeds sown, and seedling establishment was directly related to seed mass. The number of seedlings becoming established naturally on mounds ranged from 0.1 to 41 seedlings per mound for the 13 species. Natural seedling establishment and potential seedling establishment were not directly related. Instead, natural seedling establishment on mounds was correlated with species' frequency of occurrence off mounds. This suggests that seed availability may be more important than seedling establishment in controlling seedling density on mounds. However, if seed availability is unlimited or equal among species, then seedling establishment could control seedling density on disturbed ground. Key words: disturbance, seedling density, old field.
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Petru, Martina, and Eric S. Menges. "Seedling Establishment in Natural and Experimental Florida Scrub Gaps." Journal of the Torrey Botanical Society 130, no. 2 (April 2003): 89. http://dx.doi.org/10.2307/3557533.
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Seminario Peña, Joselyn Vanessa, Alejandra Nieto-Garibay, Enrique Troyo-Diéguez, Bernardo Murillo-Amador, Alfonso Medel-Narváez, and Teresa Terrazas. "Physiological and morphometric characteristics of Pachycereus pringlei (S.Watson) Britton & Rose seedlings applying organic manures." Journal of the Professional Association for Cactus Development 25 (May 22, 2023): 36–59. http://dx.doi.org/10.56890/jpacd.v25i.516.
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The establishment of Pachycereus pringlei seedlings is a scarce event; soil conditions are one of the factors attributed to its high mortality rate in the early stages of development. The use of organic manures as a substrate helps to improve the structure, porosity, and density of the soil where they live, in addition to providing nutrients that would benefit the roots, increasing the possibility of their establishment during the emergence stage. The objective of this study was to evaluate the effect of different proportions of organic manures as a sown substrate in the emergence and establishment of Pachycereus pringlei seedlings, using nine treatments of organic manures in a completely randomized experimental design with four replications. The variables measured were emergence rate (ER) and percentage (EP) and their indices, seedlings’ morphometric, and physiological characteristics in the establishment stage. The results showed that the evaluated variables in the emergence and seedling establishment phase indicate the preference for natural substrate and organic manure combinations in proportions of 50 and 30%, respectively. The analysis of variance showed significant differences regarding the morphometric and physiological variables of the stem and root of the evaluated treatments. The emergence and establishment analyses show that cardon seedlings under different organic manure treatments and controlled conditions had excellent survival results compared to the low rates of recruitment and survival reported under natural conditions. Similarly, the implementation of organic manures improved the physiological and morphometric characteristics of the cardon seedlings compared to the control treatment with the natural substrate.
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Shepperd, Wayne D., Carleton B. Edminster, and Stephen A. Mata. "Long-Term Seedfall, Establishment, Survival, and Growth of Natural and Planted Ponderosa Pine in the Colorado Front Range." Western Journal of Applied Forestry 21, no. 1 (January 1, 2006): 19–26. http://dx.doi.org/10.1093/wjaf/21.1.19.
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Abstract Seedfall, natural regeneration establishment, and growth of planted seedlings was observed from 1981 to 2001 under shelterwood and seedtree overstories in a replicated study in ponderosa pine in the Manitou Experimental Forest in the Colorado Front Range. Good seed crops were produced only every 4 to 6 years, with almost no viable seed produced in intervening years. With seed predation, only 14% of total seedfall was available for germination. Shelterwood overstories containing between 6 and 14 m2 ha−1 stem basal area over scarified seedbeds provided optimal conditions for natural seedling establishment. Survival and growth of planted seedlings was much better than that of natural seedlings. However, poor survival and slow initial growth may require many years to establish a fully stocked forest of natural seedlings.
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Lamanauskas, Vincentas. "HUMANISATION OF NATURAL SCIENCE EDUCATION AS A PROBLEM." Problems of Education in the 21st Century 38, no. 1 (December 20, 2011): 5–7. http://dx.doi.org/10.33225/pec/11.38.5.
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The present humankind has to solve a number of serious problems. Under the threat of the ecology catastrophe, concern for physical and spiritual health care is felt. All our relations with nature turn out to be problematic. The establishment of a harmonious correlation between nature and society becomes an important task. We cannot exclusively rely on knowledge and mind in any activity as these are not overall dimensions. Enforcement of humanism, democracy and being a good citizen - these are common everyday issues in our schools today. The goal of the education reform is to make a school the place for creating a personality and not only the place to pump with knowledge.
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Loydi, Alejandro, R. Lutz Eckstein, Annette Otte, and Tobias W. Donath. "Effects of litter on seedling establishment in natural and semi-natural grasslands: a meta-analysis." Journal of Ecology 101, no. 2 (December 6, 2012): 454–64. http://dx.doi.org/10.1111/1365-2745.12033.
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Chervonenko, Oksana, and Dmytro Kepin. "Natural history museology: establishment and formation of its theoretical bases." History of science and technology 12, no. 1 (June 19, 2022): 11–30. http://dx.doi.org/10.32703/2415-7422-2022-12-1-11-30.
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The article presents a brief historical outline of the formation and development of natural history museology in Europe in the 15th–19th centuries. The development of scientific knowledge at that time affects the idea of the world order and the place of man in it, and the combination of knowledge with practical experience leads to the birth of true science. It is shown that one of the most important components of the development of natural sciences, in particular biological sciences, was the collection of naturalia (i.e. objects of natural origin), the rapid surge of interest in which contributed to the Great Geographical Discoveries. In chronological order, the further historical development of museum work from private collections in Italy to the formation of a prototype of a genuine museum, which performs the main museum functions such as amassment, storage and demonstration of collections, is considered. The role of prominent naturalists and philosophers such as F. Bacon, C. Linnaeus, and J.-W. Goethe in the development of museum work is considered and little known facts about their work in this area are presented. The first works of art that show the interiors of “Kunstkameras”, which became widespread in Europe in the 17th–18th centuries, are briefly considered. According to the authors, it is on the portrait of the Belarusian educator F. Skorina, which was published in Prague in 1517–1519, that the interior of the first Renaissance “kunstkammer” collections is depicted. Separately, the development of museology in Ukraine since the time of Yuriy Kotermak (Drohobych) (1450–1494) is considered and the differentiation of the concept of “museum” in the monuments of Ukrainian literature of the period of the 16th–18th centuries is studied. The authors considered the methodological foundations of natural history museology and analysed the existing classifications of various branches of science. The specificity of natural history museology in the system of museological science is shown, the issue of singling out natural history museology as an independent discipline is discussed. It is proved that the periodization of museology and museum work in certain territories in historical time can be considered correct; the author's development of the periodization of natural history museology in Europe is also given.
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Hasiuk, Ivan, Sergii Pudchenko, and Liubov Yablon. "Establishment of Physical Science in Precarpathia: Events and Characters." Journal of Vasyl Stefanyk Precarpathian National University 10, no. 3 (September 30, 2023): 139–44. http://dx.doi.org/10.15330/jpnu.10.3.139-144.
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The question of the development of physical science in the Carpathian region (end of the 18th - beginning of the 21st century) was studied, starting from the Tsar's Royal Gymnasium, organized in 1784, to the creation of a teacher's institute in 1940 in the city of Stanislaviv (Ivano-Frankivsk) and its gradual transformation into Vasyl Stefanyk Precarpathian National University. The role of science education and especially physics in the formation of a cohort of modern specialists, necessary for the restoration of the country and its rapid technological development, is indicated. The progress of physical education in Stanislaviv (Ivano-Frankivsk) and the development of methodological and organizational foundations for the training of future physics teachers is considered against the background of the dramatic historical and political transformations of the region in the period under study. It is shown that the beginning of the development of learning and teaching of physics was already laid in the activities of numerous gymnasium-type educational institutions, which were organized in the city since the 18th century and became training bases for future teachers or scientists, in particular natural sciences. Special attention is focused on the defining role of outstanding characters of scientists and pedagogues-physicists who made a significant contribution to the formation of modern scientific and pedagogical schools and concepts: professors Viktor Dushchenko, Petr Kyrychka, Ivan Kucheruk, Dmytro Freik, Ivan Klymyshyn, Bohdan Ostafiychuk. Despite the initiation and development of scientific directions, Vasyl Stefanyk Precarpathian National University remains an important center for the development of pedagogical ideas and innovations in the field of natural sciences and comprehensively contributes to the improvement of the methodology and didactics of physics at various levels.
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Ranva, Santosh, YV Singh, Neelam Jain, and Deva Ram Bajiya. "Influence of natural saferock mineral on soil micro-bilogical parameters under rice-wheat cropping system." Bangladesh Journal of Botany 48, no. 1 (March 31, 2019): 145–51. http://dx.doi.org/10.3329/bjb.v48i1.47433.
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A field experiment was conducted to study the effect of SafeRock Minerals (SRM) application on soil microbiological parameters in rice-wheat cropping system. The experiments consisted of two methods of rice and wheat establishment and six different levels of crop nutrition including SRM with mineral fertilizers and organic manure (FYM). The rice was grown in kharif (June to October) season through aerobic direct seeded condition and flooded transplanted system. During rabi (October to April) season wheat was cultivated by two establishment methods viz. system of wheat intensification (SWI) and conventional wheat. The high yielding varieties of Basmati rice (Pusa Basmati 1509) and wheat (HD 2967) were used in the experiment. The results revealed that the soils of rice and wheat crops showed significant improvement in available N, P and K and soil microbial parameters (enzymatic activities and microbial biomass carbon) due to the integrated application of 250 kg/ha SRM + 100% recommended dose of fertilizer (RDF) and 250 kg/ha SRM + 50% RDF (chemical) + 25% RDF (organic) and 250 kg/ha SRM + 50% organic-FYM (10.0 t/ha) over the sole SRM application under both the methods of stand establishment of rice as well as wheat.
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Mills, Nicholas. "An Alternative Perspective for the Theory of Biological Control." Insects 9, no. 4 (October 2, 2018): 131. http://dx.doi.org/10.3390/insects9040131.
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Importation biological control represents the planned introduction of a specialist natural enemy from the region of origin of an invasive pest or weed. For this study, the author considered why attempts to develop a predictive theory for biological control have been misguided and what future directions might be more promising and effective. Despite considerable interest in the theory of consumer–resource population dynamics, such theory has contributed little to improvements in the success of biological control due to a focus on persistence and equilibrium dynamics rather than establishment and impact. A broader consideration of invasion biology in addition to population ecology offers new opportunities for a more inclusive theory of biological control that incorporates the demographic and genetic processes that more specifically address the establishment and impact of introduced natural enemies. The importance of propagule size and genetic variance for successful establishment, and of contributions to host population growth, relative population growth rates, interaction strength, and coevolution for suppression of host abundance are discussed as promising future directions for a theory of biological control.
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Sobolev, Alexander E., Vladimir I. Lutsik, Tatyana N. Mukhina, and Tatyana A. Gorbunova. "INTEGRATION OF NATURAL SCIENCE EDUCATION AT THE SYSTEM “SECOND-ARY SCHOOL – HIGH EDUCATIONAL ESTABLISHMENT”." GAMTAMOKSLINIS UGDYMAS / NATURAL SCIENCE EDUCATION 6, no. 1 (March 1, 2009): 47–54. http://dx.doi.org/10.48127/gu-nse/09.6.47.
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In this article, the experience of the creation and examination of the continuous natural science educational system “secondary school – high educational establishment” at the Tver State Technical University and the municipal educational establishment “Secondary school No. 45 of Tver” was discussed. The basic forms of such collaboration were considered, and its concrete examples were given. It is shown that the correct organization of the integration process promotes improvement of the quality of education and the perfection of the educational and scientific processes both at the school and in the university. An approbation of the idea of development of the senior profile school as one of the segments of the regional scientifically-educational complex and its transformation into the professional senior school was put in the basis of the system of continuous natural science education. Sharing of the material resources of school and university has brought the essential contribution to the development of the educational process, has enriched it with the variety of new possibilities. In particular, the integrated approach to the application of modern software and hardware has allowed creating the uniform multimedia lecture&laboratory complex using the majority of modern educational technologies. The successful example of the integration of natural science education in the system “secondary school – university” was realization of the joint project of Tver State Technical University and secondary school no. 45. This project was devoted to the working out and application of new educational technologies and models of continuous natural science education on the basis of use of the modern educational equipment for studying of nanotechnology and nanomaterials (in addition to the existing sections of the school pro-gram on physics, chemistry and biology). Being unique in Tver region, this laboratory is working now both for schoolboys and for students. It is found that performance of this project not only promoted the equip-ment development of the educational process but also has led to the essential updating and perfection of its methodical part and content. Key words: Integration, secondary school, high educational establishment, natural science education.
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Bokonon-Ganta, Aimé H., Grant T. McQuate, and Russell H. Messing. "Natural establishment of a parasitoid complex on Bactrocera latifrons (Diptera: Tephritidae) in Hawaii." Biological Control 42, no. 3 (September 2007): 365–73. http://dx.doi.org/10.1016/j.biocontrol.2007.05.019.
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Yakovlev, A. S. "Issues of Environmental Regulation and Establishment of Background Values of Soil Properties of Natural and Natural Anthropogenic Objects." Eurasian Soil Science 55, no. 2 (February 2022): 262–68. http://dx.doi.org/10.1134/s1064229322020144.
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Stein, Steven J., and Diana N. Kimberling. "Germination, Establishment, and Mortality of Naturally Seeded Southwestern Ponderosa Pine." Western Journal of Applied Forestry 18, no. 2 (April 1, 2003): 109–14. http://dx.doi.org/10.1093/wjaf/18.2.109.
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Abstract Information on the mortality factors affecting naturally seeded conifer seedlings is becoming increasingly important to forest managers for both economic and ecological reasons. Mortality factors affecting ponderosa pine (Pinus ponderosa) seedlings immediately following natural germination and through the following year were monitored in Northern Arizona. The four major mortality factors in temporal order included the failure of roots to establish in the soil (27%), herbivory by lepidopteran larvae (28%), desiccation (30%), and winterkill (10%). These mortality factors were compared among seedlings germinating in three different overstory densities and an experimental water treatment. Seedlings that were experimentally watered experienced greater mortality than natural seedlings due to herbivory (40%), nearly as much mortality due to the failure of roots to establish in the soil (20%), less mortality due to winterkill (5%), and no mortality due to desiccation. The seedling mortality data through time were summarized using survivorship curves and life tables. Our results suggest that managers should consider using prescribed burns to decrease the percentage of seedlings that die from failure of their roots to reach mineral soil and from attack by lepidopteran larvae. West. J. Appl. For. 18(2):109–114.
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Green, Ken. "Causes of stability in the alpine treeline in the Snowy Mountains of Australia - a natural experiment." Australian Journal of Botany 57, no. 3 (2009): 171. http://dx.doi.org/10.1071/bt09052.
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Large areas of treeline in the Snowy Mountains of south-eastern Australia burnt in wildfires in 2003, providing the opportunity to quantify seedling establishment at the treeline after disturbance, by comparing burnt and unburnt sites. Eucalyptus pauciflora niphophila (Maiden and Blakely) L. Johnson and Blakely, (snowgum) generally responds to fire by resprouting from lignotubers rather than by the death of the tree, hence the location of the pre-fire treeline was unaffected. Burnt and unburnt sites along the treeline therefore differed in the removal of immediate competition from understorey plants and loss of a protective canopy shelter. Five years after these fires, 27 sites were examined to determine whether the resulting conditions led to increased establishment of snowgums above the treeline. Paired plots 15 m wide were established, extending a distance of 15 m above and below the treeline in 15 unburnt and 12 burnt sites. There were significantly more seedlings in burnt than unburnt plots below the treeline. However, even in burnt areas, there were significantly fewer seedlings found above the treeline than below the treeline. Although conditions for seedling establishment at the treeline were good at burnt sites (as indicated by seedling recruitment within 15 m of the treeline), this major disturbance by fires resulted in no pulse of seedling establishment above the treeline. It is concluded that stability in the treeline of the Snowy Mountains is likely to be due to the failure of seeds to disperse uphill.
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Hovstad, Knut Anders, and Mikael Ohlson. "Physical and chemical effects of litter on plant establishment in semi-natural grasslands." Plant Ecology 196, no. 2 (September 6, 2007): 251–60. http://dx.doi.org/10.1007/s11258-007-9349-y.
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Bindewald, A., S. Miocic, A. Wedler, and J. Bauhus. "Forest inventory-based assessments of the invasion risk of Pseudotsuga menziesii (Mirb.) Franco and Quercus rubra L. in Germany." European Journal of Forest Research 140, no. 4 (March 26, 2021): 883–99. http://dx.doi.org/10.1007/s10342-021-01373-0.
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AbstractIn Europe, some non-native tree species (NNT) are classified as invasive because they have spread into semi-natural habitats. Yet, available risk assessment protocols are often based on a few limited case studies with unknown representativeness and uncertain data quality. This is particularly problematic when negative impacts of NNT are confined to particular ecosystems or processes, whilst providing valuable ecosystem services elsewhere. Here, we filled this knowledge gap and assessed invasion risks of two controversially discussed NNT in Germany (Quercus rubra L., Pseudotsuga menziesii (Mirb.) Franco) for broad forest types using large scale inventory data. For this purpose, establishment success of natural regeneration was quantified in terms of cover and height classes. The current extent of spread into protected forest habitats was investigated in south-west Germany using regional data. Establishment was most successful at sites where the NNT are abundant in the canopy and where sufficient light is available in the understory. Natural regeneration of both NNT was observed in 0.3% of the total area of protected habitats. In forest habitats with sufficient light in the understory and competitively inferior tree species, there is a risk that Douglas fir and red oak cause changes in species composition in the absence of management interventions. The installation of buffer zones and regular removal of unwanted regeneration could minimize such risks for protected areas. Our study showed that forest inventories can provide valuable data for comparing the establishment risk of NNT amongst ecosystem types, regions or jurisdictions. This information can be improved by recording the abundance and developmental stage of widespread NNT, particularly in semi-natural ecosystems.
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Shaw, P. W., P. Lo, and D. R. Wallis. "Recent introduction and establishment of the leafroller parasitoid Trigonospila brevifacies (Hardy) (Diptera Tachinidae) in Nelson." New Zealand Plant Protection 54 (August 1, 2001): 33–36. http://dx.doi.org/10.30843/nzpp.2001.54.3735.
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To assist the natural distribution of the leafroller parasitoid Trigonospila brevifacies to horticultural areas in the Nelson region 181 T brevifacies pupae and 329 adults were released in 1999 at four sites adjacent to apple orchards near Motueka Release material was supplied from fieldcollected parasitoids in Hawkes Bay and a laboratory colony held at the Mt Albert Research Centre in Auckland Successful establishment of the parasitoid was recorded at all four sites and at a nearby nonrelease site in 2000 In 2000 319 of fourth instar and older larvae were parasitised by T brevifacies while in 2001 parasitism was 1166 Important pest tortricid species including Epiphyas postvittana (Walker) (lightbrown apple moth) were among the hosts The successful establishment of T brevifacies in Nelson and its further natural dispersal will increase the potential for the reduction of economically important leafroller species by biocontrol agents
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Cain, Michael D., and James P. Barnett. "Effects of Early Release on Natural Versus Container Loblolly Pines 12 Years After Field Establishment." Southern Journal of Applied Forestry 26, no. 4 (November 1, 2002): 173–80. http://dx.doi.org/10.1093/sjaf/26.4.173.
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Abstract Genetically improved, container loblolly pine (Pinus taeda L.) seedlings were compared to naturally established loblolly seedlings on a cutover pine site. Crop pines on 6 of 12 plots were released from woody and herbaceous competition within a 2 ft radius of each stem. On release plots, woody competition was controlled by hand-cutting for 5 consecutive yr and herbaceous competition was controlled with herbicides for 4 consecutive yr after pine establishment. Competition control increased 12 yr survival by 68 percentage points for natural pines and by 47 percentage points for planted pines. Twelve years after field establishment, mean-tree volume of planted pines was no different than that of naturally established pines. Nevertheless, volume gains of 150% to 200% were achieved within regeneration techniques as a result of release. South. J. Appl. For. 26(4):173–180.
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Vignoni, Ana Paz, Iris Edith Peralta, and Elena María Abraham. "Fragmented areas due to agricultural activity: native vegetation dynamics at crop interface (Montecaseros, Mendoza, Argentina)." Revista de la Facultad de Ciencias Agrarias UNCuyo 55, no. 2 (November 21, 2023): 46–60. http://dx.doi.org/10.48162/rev.39.108.
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Plant communities fragmented by agricultural activities were analyzed in a 250-ha area in eastern plains of Montecaseros, Gral. San Martín Department, Mendoza, Argentina. A phytosociological method assessed different sites along a gradient of human intervention, from natural environments with no evidence of altered native vegetation to maximum farming modification, also including cleared and abandoned fields. Soil analyses supplemented the characterization of six plant communities. A scrubland physiognomy dominates the area, with species of the genera Larrea, Atriplex and Lycium. Tillage and crop abandonment can alter natural factors involved in soil formation, causing deterioration and exerting selective pressure on species colonizing these degraded environments. Evaluating natural vegetation before land clearing for agriculture is essential to assess, through species that indicate environmental conditions, edaphic limitations hindering crop establishment and affecting productivity. The conservation of natural communities on private lands destined for agriculture is valued. Plant communities fragmented by agricultural activities were analyzed in a 250-ha area in eastern plains of Montecaseros, Gral. San Martín Department, Mendoza, Argentina. A phytosociological method assessed different sites along a gradient of human intervention, from natural environments with no evidence of altered native vegetation to maximum farming modification, also including cleared and abandoned fields. Soil analyses supplemented the characterization of six plant communities. A scrubland physiognomy dominates the area, with species of the genera Larrea, Atriplex and Lycium. Tillage and crop abandonment can alter natural factors involved in soil formation, causing deterioration and exerting selective pressure on species colonizing these degraded environments. Evaluating natural vegetation before land clearing for agriculture is essential to assess, through species that indicate environmental conditions, edaphic limitations hindering crop establishment and affecting productivity. The conservation of natural communities on private lands destined for agriculture is valued. Highlights: This study aimed to characterize plant communities in natural and intervened environments, in a representative area of the fragmentation processes caused by agriculture in the Monte Province (Mendoza, Argentina). Plant biodiversity plays a strategic role in ecosystemic provision of goods and services necessary to human health and well-being. Cultivable land is a vulnerable and scarce resource, particularly in drylands, where ecosystems have low capacity for natural regeneration. Tillage and crop abandonment can alter natural factors involved in soil formation, causing deterioration and exerting selective pressure on species colonizing these degraded environments. In agricultural land, clearing can give rise to a mosaic of landscapes: productive crops merge with abandoned crops and fragments of natural fields. Evaluating natural vegetation before land clearing for agriculture is essential to assess, through species that indicate environmental conditions, edaphic limitations hindering crop establishment and affecting productivity. Studies of vegetation dynamism in private lands contribute to plan and implement sustainable land management, tending to recover and conserve biodiversity in degraded soils, considering all associated ecosystem services.
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Kharitonova, Ludmila S. "Polytechnic Library (To the 145th Anniversary of Establishment)." Bibliotekovedenie [Russian Journal of Library Science], no. 6 (December 2, 2009): 102–6. http://dx.doi.org/10.25281/0869-608x-2009-0-6-102-106.
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Describes the history of creation and forming of one of the oldest Russian libraries stock, developed from the restricted library of the natural science amateur association towards to the huge public library.
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Lozon, J. D., and H. J. MacIsaac. "Biological invasions: are they dependent on disturbance?" Environmental Reviews 5, no. 2 (June 2, 1997): 131–44. http://dx.doi.org/10.1139/a97-007.
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We utilize literature surveys to examine the relationship between establishment of exotic species and human or natural disturbances of ecosystems. Of the 133 papers published in 10 ecological journals between 1993 and 1995, 63 reported on field studies involving 299 and 103 successful, nonredundant plant and animal introductions, respectively. Invasions of terrestrial ecosystems dominated (>>97%) the surveyed literature. Disturbance was associated with establishment of exotic species in 56% of these studies, though its importance differed among papers describing plants (68%) and animals (28%). Plants species (86%) were significantly more dependent on disturbance for establishment than were animals (12%). However, animals and plants that were dependent on disturbance for establishment were almost equally dependent (58 versus 68%) on it for range expansion. In a second survey, 402 plant and 103 animal taxa were identified that explicitly linked establishment of exotic species to disturbance. Human activities were attributed with establishment of species in 97 and 57% of these cases, respectively. Common mechanisms associated with establishment of exotic animals included ballast water discharge, intentional releases, and residential development. Establishment of exotic plants was associated with animal activities (e.g., grazing, seed introduction), soil disturbance, forestry, fire, agriculture, and human activities. In contrast to invasions theory, our survey indicates that the association between establishment and spread of exotic species and disturbance ought not be assumed a priori. Some animals repeatedly invade new habitats once geographic barriers are circumvented, indicating that communities may be more receptive to exotic species than previously acknowledged. By contrast, introduced plants established most often in disturbed habitats.
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Cole, Ian, Ian D. Lunt, and Terry Koen. "Effects of soil disturbance, weed control and mulch treatments on establishment of Themeda triandra (Poaceae) in a degraded white box (Eucalyptus albens) woodland in central western New South Wales." Australian Journal of Botany 52, no. 5 (2004): 629. http://dx.doi.org/10.1071/bt04010.
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Temperate grassy woodlands are endangered ecosystems in Australia, and many degraded remnants are in desperate need of understorey restoration. This experiment compared the effects of soil disturbance, weed control and mulch treatments on establishment of the original dominant grass, Themeda triandra Forssk., in a degraded white box (Eucalyptus albens Benth.) woodland at Cowra in central New South Wales (NSW). Awned Themeda seeds were surface-sown into replicated plots treated as follows: soil scalping, soil disturbance (by ripping), herbicide (simazine) application and retention of natural mulch. Scalping combined with soil disturbance best promoted Themeda establishment (47.8% after 40 days and 28% after 518 days), and also reduced broadleaf-herb densities. By contrast, scalping without soil disturbance had the worst effect on Themeda establishment (5.2% after 40 days and 4.5% after 518 days). Disturbance significantly enhanced Themeda establishment and decreased the density of annual grasses and the basal cover of non-Themeda species. By contrast, the retention of 500–800 kg of natural surface mulch had no apparent effect on Themeda establishment. Contrary to expectations, simazine reduced the density and basal cover of all species, including Themeda, which is normally resistant to this herbicide. All combinations of the mulched, disturbed and herbicide treatments (i.e. all treatments except scalping) gave similar results, ranging from 10.7 to 22.0 Themeda plants m–2 after 518 days. These results suggest that Themeda stands can be established in degraded box woodlands by using awned seed materials, with minimal seedbed preparation and simple sowing techniques. Further studies are required to determine whether established swards can resist weed invasion in the absence of ongoing weed management, and whether establishment success varies with soil conditions and landscape position.
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Löf, Magnus, Julien Barrere, Mattias Engman, Linda K. Petersson, and Adrian Villalobos. "The influence of fencing on seedling establishment during reforestation of oak stands: a comparison of artificial and natural regeneration techniques including costs." European Journal of Forest Research 140, no. 4 (March 1, 2021): 807–17. http://dx.doi.org/10.1007/s10342-021-01369-w.
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AbstractIn temperate Europe, oak-dominated forests are widespread, supporting high biodiversity and providing important ecosystem services. Insufficient natural regeneration has, however, been a concern for over a century. The objective of this study was to gain insights into differences in regeneration success using artificial and natural regeneration techniques for reforestation of oak (Quercus robur L.) stands. We monitored seedlings following planting, direct seeding and natural regeneration over five years in a randomized block experiment in southern Sweden with fenced and non-fenced plots. Fencing had a strong positive effect on height growth, especially for planted seedlings that were taller than the other seedlings and more frequently browsed in non-fenced plots. In contrast, there was little effect of fencing on survival, establishment rate and recruitment rate of seedlings. Due to aboveground damage on seedlings from voles, protection of acorns did not improve establishment rate following direct seeding. Under current circumstances at the site with a sparse shelterwood of old oaks, we conclude that natural regeneration was the most cost-efficient regeneration method. It resulted in the most seedlings at the lowest cost. However, regeneration success was heavily influenced by interference from herbaceous vegetation. With a small additional investment in vegetation control, the results might have been improved for planting and direct seeding.
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Van De Walle, Ruben, François Massol, Martijn L. Vandegehuchte, and Dries Bonte. "The distribution and impact of an invasive plant species (Senecio inaequidens) on a dune building engineer (Calamagrostis arenaria)." NeoBiota 72 (March 4, 2022): 1–23. http://dx.doi.org/10.3897/neobiota.72.78511.
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Disturbance is thought to enhance the probability of invasive species establishment, a prerequisite for naturalisation. Coastal dunes are characterised by disturbance in the form of sand dynamics. We studied the effect of this disturbance on the establishment and spread of an invasive plant species (Senecio inaequidens) in European coastal dunes. Local sand dynamics dictate the spatial configuration of marram grass (Calamagrostis arenaria). Therefore, marram grass configuration was used as a reliable proxy for disturbance. Since marram grass plays a crucial role in natural dune formation, we evaluated the possible effects S. inaequidens could have on this process, if it is able to naturalise in European coastal dunes. We expected the highest probability of S. inaequidens establishment at intermediate marram grass cover because too low cover would increase sand burial, whereas high cover would increase competition. However, our results indicate that S. inaequidens is quite capable of handling higher levels of sand burial. Thus, the probability of S. inaequidens establishment was high under low marram cover but slightly lowered when marram cover was high, hinting at the importance of competition. We expected a negative impact of Senecio-altered soils on marram grass growth mediated by soil biota. However, marram grass grew better in sand gathered underneath Senecio plants due to abiotic soil modifications. This enhanced growth may be caused by Senecio leaf litter elevating nutrient concentrations in an otherwise nutrient-poor substrate. If such increased plant growth is a general phenomenon, further expansion of S. inaequidens could accelerate natural succession in European coastal dunes.
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Cain, M. D. "Site-Preparation Techniques for Establishing Natural Pine Regeneration on Small Forest Properties." Southern Journal of Applied Forestry 11, no. 1 (February 1, 1987): 41–45. http://dx.doi.org/10.1093/sjaf/11.1.41.
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Abstract Lightweight mechanical equipment, prescribed fire, herbicides, and handtools were used in various combinations to site-prepare small brush-filled openings within uneven-aged loblolly-shortleaf (Pinus taeda L.-P. echinata Mill.) pine stands in southern Arkansas. All treatments were effective in facilitating establishment of pine seedlings from natural seedfall when compared to untreated controls. Treatments tested in this study should have practical application on small forest properties. South. J. Appl. For. 11(1):41-45.
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Nieves-Aldrey, Jose Luis, Diego Gil-Tapetado, Oscar Gavira, Juan R. Boyero, Carlo Polidori, Maria J. Lombardero, Diana Blanco, et al. "Torymus sinensis Kamijo, a biocontrol agent against the invasive chestnut gall wasp Dryocosmus kuriphilus Yasumatsu in Spain: its natural dispersal from France and the first data on establishment after experimental releases." Forest Systems 28, no. 1 (June 7, 2019): e001. http://dx.doi.org/10.5424/fs/2019281-14361.
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Aim of study: The globally invasive gall wasp, Dryocosmus kuriphilus Yasumatsu, 1951 (Cynipidae: Cynipini), reached Spain seven years ago and is already regarded as an important pest of chestnuts (Castanea spp.) in this country as well as worldwide. In this paper, we present comprehensive data on the establishment in Spain of Torymus sinensis Kamijo, 1982 (Chalcidoidea: Torymidae), an effective non-native natural enemy of this pest, as a result of both natural dispersal and settlement after controlled releases since 2015.Area of study: Sites of the Spanish autonomous communities of Galicia, Asturias, Basque Country, Catalonia, Andalusia and Madrid where D. kuriphilus is present.Material and methods: To study the natural dispersal of T. sinensis from France, we selected two sampling sites in Catalonia, six in the Basque Country and two in Navarra known for their heavy Asian chestnut gall wasp (ACGW) infestation; to study T. sinensis establishment after authorized controlled releases by the concerned authorities, the field samplings were done mainly in Galicia (35 sites) and Andalusia (8 sites). Additionally an experimental release study was made in Madrid.Main Results: Our results showed that T. sinensis has spread throughout Spain by natural dispersal across the French border and now occurs in Catalonia (two sites), the Basque Country (three sites) and Navarra (one site) but not in the neighbouring region of Cantabria. The percentage of parasitism by T. sinensis on D. kuriphilus is higher in the Basque Country sites, which are close to the French border, thus indicating that its establishment in these localities is not recent. After controlled releases, T. sinensis has been successfully established in five release sites in Andalusia (Valle del Genal and Sierra Blanca, Málaga Province) and one release site in Madrid. However, in the region of Galicia (NW Spain), where the number of authorized releases has been higher, the establishment of T. sinensis still appears to be very low.Research highlights: Established populations of T. sinensis may exert a positive buffer against D. kuriphilus-driven chestnut infestation in Spain, similar to what is observed in other invaded European countries.Additional Keywords: Controlled releases, Torymidae, invasive species, Cynipidae, natural spread, biological control.Abbreviations used: Asian chestnut gall wasp (ACGW); Torymus sinensis parasitism rate (TsPR); mean of ACGW larval chambers per gall (MACGW).
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Hilaire, Ngoma Tassoulou. "Metaphysical Principles of the Science of Nature and Phenomenology in Emmanuel Kant." Journal of Advances in Education and Philosophy 6, no. 10 (October 21, 2022): 511–20. http://dx.doi.org/10.36348/jaep.2022.v06i10.002.
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This article, which shows the relationship between the metaphysical principles of natural science and phenomenology, shows precisely how Immanuel Kant, through these principles, contributed to the establishment of the phenomenology of perception. Thus, this article which first shows how Immanuel Kant was able to interpret and understand nature from its metaphysical principles, shows precisely and finally how the phenomenology of perception only became possible through the understanding of its principles. This is why the article then shows how these metaphysical principles of natural science are set up as the condition of possibility of the phenomenology of perception in Husserl and Merleau-Ponty.
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Dozier, Hallie, James F. Gaffney, Sandra K. McDonald, Eric R. R. L. Johnson, and Donn G. Shilling. "Cogongrass in the United States: History, Ecology, Impacts, and Management." Weed Technology 12, no. 4 (December 1998): 737–43. http://dx.doi.org/10.1017/s0890037x0004464x.
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Cogongrass is a weed throughout the tropics and subtropics. Introductions early this century have spread into forests, rangelands, reclaimed mined areas, roadsides, and natural ecosystems in the southeastern United States. Vegetative reproduction is the primary mechanism for survival and local spread, and sexually produced seeds of this obligate outcrossing species provide natural long-distance dispersal. Highly germinable (≥ 90%) seeds have no dormancy, though spikelet fill may be low (≤ 40%) in natural populations. Early seedling establishment, prior to rhizome development, is low (< 20%), occurring in areas with little competition; ≥ 75% bahiagrass sod cover is required to prevent cogongrass seedling establishment. Imazapyr and glyphosate are the most effective herbicides for cogongrass control. Younger cogongrass shoots are very susceptible to these herbicides; however, longer term control of adult plants requires translocation and thereby control of the rhizomes. Autumn applications of glyphosate and imazapyr provided greatest suppression of rhizome regrowth. Effective cogongrass management options exist and depend on integrating several control strategies. Mechanical control alone provides short-term control, whereas multiple discings plus herbicide application provide longer term control. Some combinations of herbicide, discing, and revegetation with desirable plant species provide excellent control. Because of the large geographic area infested with cogongrass and the often economically and environmentally unacceptable management techniques, biological control organisms also should be researched.
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Carralero, Pamela. "Scientific Modeling and the Environment: Toward the Establishment of Michel Serres's Natural Contract." Telos 2020, no. 190 (2020): 53–75. http://dx.doi.org/10.3817/0320190053.
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Kovaleva, Tatiana, Ramsia Absalyamova, and Elena Fomina. "Psychological-pedagogical aspects of teaching the foreign language to students of natural-science faculties." KANT 35, no. 2 (June 2020): 250–54. http://dx.doi.org/10.24923/2222-243x.2020-35.52.
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The article deals with the role and place of the discipline "Foreign language" in the professional training of students of natural science faculties. The most typical reasons are identified for the low language training of students of non-linguistic areas in a higher educational establishment. In this regard, the necessity of realization of individual approach to each student taking into account his psychological and pedagogical features is proved. The dominant pedagogical principles are considered of teaching a foreign language to students of non-linguistic specialties.
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Gerard, P. J., T. M. Eden, D. J. Wilson, and G. Burch. "Distribution of the clover root weevil biocontrol agent in the North Island of New Zealand." New Zealand Plant Protection 61 (August 1, 2008): 24–30. http://dx.doi.org/10.30843/nzpp.2008.61.6828.
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The Irish wasp Microctonus aethiopoides was released in 2006 as a biocontrol agent for the clover root weevil Sitona lepidus a serious pest of white clover in New Zealand Following successful establishment two strategies were implemented to accelerate the widespread establishment of the parasitoid throughout the North Island The first approach was the establishment of regional nursery sites that act as point sources for natural and assisted dispersal With the assistance of Regional Councils and major landowners these were set up at sites favourable to the wasp and local people were provided the training and support to undertake collections and distribution of parasitized weevils Secondly samples of parasitized weevils were distributed for release directly to farmers through pastoral industry networks and events Initial results indicate that while the parasitoid established rapidly at Taranaki and Waikato nursery sites as anticipated it has failed to establish in Northland in two successive seasons
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Bhagat, Suraj Kumar, Tiyasha Tiyasha, Zainab Al-khafaji, Patrick Laux, Ahmed A. Ewees, Tarik A. Rashid, Sinan Salih, Roland Yonaba, Ufuk Beyaztas, and Zaher Mundher Yaseen. "Establishment of Dynamic Evolving Neural-Fuzzy Inference System Model for Natural Air Temperature Prediction." Complexity 2022 (September 23, 2022): 1–17. http://dx.doi.org/10.1155/2022/1047309.
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Air temperature (AT) prediction can play a significant role in studies related to climate change, radiation and heat flux estimation, and weather forecasting. This study applied and compared the outcomes of three advanced fuzzy inference models, i.e., dynamic evolving neural-fuzzy inference system (DENFIS), hybrid neural-fuzzy inference system (HyFIS), and adaptive neurofuzzy inference system (ANFIS) for AT prediction. Modelling was done for three stations in North Dakota (ND), USA, i.e., Robinson, Ada, and Hillsboro. The results reveal that FIS type models are well suited when handling highly variable data, such as AT, which shows a high positive correlation with average daily dew point (DP), total solar radiation (TSR), and negative correlation with average wind speed (WS). At the Robinson station, DENFIS performed the best with a coefficient of determination (R2) of 0.96 and a modified index of agreement (md) of 0.92, followed by ANFIS with R2 of 0.94 and md of 0.89, and HyFIS with R2 of 0.90 and md of 0.84. A similar result was observed for the other two stations, i.e., Ada and Hillsboro stations where DENFIS performed the best with R2: 0.953/0.960, md: 0.903/0.912, then ANFIS with R2: 0.943/0.942, md: 0.888/0.890, and HyFIS with R2: 0.908/0.905, md: 0.845/0.821, respectively. It can be concluded that all three models are capable of predicting AT with high efficiency by only using DP, TSR, and WS as input variables. This makes the application of these models more reliable for a meteorological variable with the need for the least number of input variables. The study can be valuable for the areas where the climatological and seasonal variations are studied and will allow providing excellent prediction results with the least error margin and without a huge expenditure.
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Pinno, B. D., and R. C. Errington. "Maximizing Natural Trembling Aspen Seedling Establishment on a Reclaimed Boreal Oil Sands Site." Ecological Restoration 33, no. 1 (February 12, 2015): 43–50. http://dx.doi.org/10.3368/er.33.1.43.
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Zhao, Wanying, Charles Goebel, and John Cardina. "Temporal and Spatial Pattern of a Privet (Ligustrum vulgare) Invasion." Invasive Plant Science and Management 6, no. 2 (June 2013): 310–19. http://dx.doi.org/10.1614/ipsm-d-12-00057.1.
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AbstractPrivet has escaped from cultivation and is invading natural areas throughout eastern North America. Understanding the pattern of invasion over time could help us develop more efficient management strategies. We studied the invasion history and spatial distribution pattern of privet by mapping age and spatial data for established patches in a 132-ha (326 ac) forested natural area in northeast Ohio. We determined the age of 331 geo-referenced patches by counting annual rings, and mapped them with corresponding land habitat. Age distribution and cumulative number of privet patches over about 40 yr showed three phases of invasion. The initial 19-yr lag phase was characterized as a dispersed spatial pattern (based on nearest neighbor analysis), with patches located mostly at edges of different habitats and open places. In a second phase of about 15 yr, an average of 19 patches were initiated yearly, in a pattern that trended towards clustered. The final phase began around 2007, as the rate of new patch establishment declined, possibly because of saturation of the suitable habitat. Establishment of new patches was not associated with specific habitats. Aggregation of patches with similar ages increased after 1998 and became significantly clustered. Mapping of clusters of old and young patches identified invasion hot spots and barriers. Results affirmed that the best time for invasive control is during the lag phase. By monitoring edge habitats associated with early establishment, managers might detect and control early invaders and delay the onset of the expansion phase.
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Xiong, Ying, and Shengsheng Li. "Can the Establishment of University Science and Technology Parks Promote Urban Innovation? Evidence from China." Sustainability 14, no. 17 (August 28, 2022): 10707. http://dx.doi.org/10.3390/su141710707.
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China’s university science and technology parks (USTPs) were established with the aim of closely combining the scientific and educational intellectual resources of universities with the advantageous innovation resources of the market to form a fusion of industry and education. This paper uses the establishment of national university science and technology parks (NUSTPs) as a “quasi-natural experiment.” We used the panel data of 293 cities from 1999 to 2017 as a sample to analyze the impact of NUSTP establishment on urban innovation, using the difference-in-difference method. The research found the following: (1) The establishment of NUSTPs significantly improves the level of urban innovation, and the conclusion is still valid after a series of robustness tests. The urban innovation effect of the establishment of NUSTPs is dynamic, non-lagging, and continuous. (2) The innovation effect differs significantly, depending on the city region, the city scale, and the university level. Specifically, the innovation effect of the establishment of NUSTPs is significant for cities in middle and western cities, large-scale cities, and cities with double first-class and local universities setting up USTPs, while the effect is not significant for cities in eastern cities, small- and medium-scale cities, and non-double first-class and ministry-affiliated institutions. (3) The impact mechanism test shows that NUSTPs contribute to urban innovation by increasing the city’s human capital, enhancing the degree of industrial agglomeration, and creating an innovation space effect.
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Selig, Christian, Friederike de Mol, Paula R. Westerman, and Bärbel Gerowitt. "Quantifying seed and establishment limitation to seedling recruitment of arable weeds: an example of barnyardgrass (Echinochloa crus-galli)." Weed Science 70, no. 1 (October 22, 2021): 87–94. http://dx.doi.org/10.1017/wsc.2021.68.
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AbstractThe establishment of plants in an ecosystem is limited by the availability of seeds and the availability of suitable sites for establishment. Describing plant population dynamics through the relative strength of seed and establishment limitation is an important concept in the study of natural ecosystems. To date, it is unclear whether this concept can be applied to describe populations of annual weeds in agricultural fields. Using a recruitment function, we show that limitation parameters prove valuable in describing seedling recruitment in weed populations. We conducted a seed addition experiment in three cornfields (Zea mays L.) and recorded seedling recruitment in populations of the economically important weed barnyardgrass [Echinochloa crus-galli (L.) P. Beauv.]. Seed predation, competition with other weeds, and seed burial were prevented. We estimated the strength of seed and establishment limitation in the population with two parameters: n, which is the number of microsites, and b, which is the suitability of those sites to support a seedling. We further estimated the relative proportions of density-dependent and density-independent establishment limitation in the seedling population. Recruitment rates of E. crus-galli ranged from 31% to 36% across all evaluated seed densities and fields, which is high compared with results from other seed addition studies. Two of the three monitored populations were predominantly establishment limited at the highest evaluated seed density of 2,400 added seeds m−2. Further knowledge about the relative strength of limitations in other weed populations will provide important information on how effective different weed management strategies can be.
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Argov, Yael, and Yoav Gazit. "Biological control of the Mediterranean fruit fly in Israel: Introduction and establishment of natural enemies." Biological Control 46, no. 3 (September 2008): 502–7. http://dx.doi.org/10.1016/j.biocontrol.2008.04.021.
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Pickett, CH, W. Roltsch, and A. Corbett. "The role of a rubidium marked natural enemy refuge in the establishment and movement ofBemisiaparasitoids." International Journal of Pest Management 50, no. 3 (July 2004): 183–91. http://dx.doi.org/10.1080/09670870410001731916.
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Otfinowski, R., N. C. Kenkel, P. Dixon, and J. F. Wilmshurst. "Integrating climate and trait models to predict the invasiveness of exotic plants in Canada’s Riding Mountain National Park." Canadian Journal of Plant Science 87, no. 5 (December 1, 2007): 1001–12. http://dx.doi.org/10.4141/cjps07117.
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Invasive exotic species threaten the biodiversity and function of native ecosystems. Existing models, attempting to predict successful invaders, often emphasize isolated stages of biological invasions and fail to formalize interactions between exotic species and recipient environments. By integrating the native climatic range and biological traits of exotic vascular plants reported inside and outside Riding Mountain National Park, Manitoba, Canada, we present a model where invasion risk is predicted using the likelihood of establishment and proliferation of exotic species. Exotic vascular plants constituted 11.5% (77/669) of the total vascular flora of Riding Mountain National Park and approximately 14.2% (202/1418) of the flora of Manitoba. Based on their climatic range in Europe, 155 among 174 exotic species absent from the Park, including those found in Manitoba and other natural areas in Canada, were predicted to establish within its boundaries. Among the biological traits of exotic plants, perenniality and vegetative reproduction correctly identified 61% of documented invaders of natural areas in Canada and helped to further define a subset of 40 exotic plants with the highest potential to proliferate within the Park’s natural areas. Among these, 11 are still absent from inside its boundaries and 17 are not yet reported in Manitoba. Our results demonstrate that Riding Mountain National Park and natural areas in western Canada will continue to be impacted by exotic vascular plants. By integrating establishment and proliferation, key stages in the progress of biological invasions, our model offers a synthetic approach to the prediction and management of biological invasions inside natural areas; such integration is critical to the protection of Canada’s endemic biodiversity. Key words: Biological invasions, invasive alien plants, climate-matching model, life history, natural areas, risk assessment
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Huang, K., J. Bahl, X. H. Fan, D. Vijaykrishna, C. L. Cheung, R. J. Webby, R. G. Webster, et al. "Establishment of an H6N2 Influenza Virus Lineage in Domestic Ducks in Southern China." Journal of Virology 84, no. 14 (May 12, 2010): 6978–86. http://dx.doi.org/10.1128/jvi.00256-10.
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ABSTRACT Multiple reassortment events between different subtypes of endemic avian influenza viruses have increased the genomic diversity of influenza viruses circulating in poultry in southern China. Gene exchange from the natural gene pool to poultry has contributed to this increase in genetic diversity. However, the role of domestic ducks as an interface between the natural gene pool and terrestrial poultry in the influenza virus ecosystem has not been fully characterized. Here we phylogenetically and antigenically analyzed 170 H6 viruses isolated from domestic ducks from 2000 to 2005 in southern China, which contains the largest population of domestic ducks in the world. Three distinct hemagglutinin lineages were identified. Group I contained the majority of isolates with a single internal gene complex and was endemic in domestic ducks in Guangdong from the late 1990s onward. Group II was derived from reassortment events in which the surface genes of group I viruses were replaced with novel H6 and N2 genes. Group III represented H6 viruses that undergo frequent reassortment with multiple virus subtypes from the natural gene pool. Surprisingly, H6 viruses endemic in domestic ducks and terrestrial poultry seldom reassort, but gene exchanges between viruses from domestic ducks and migratory ducks occurred throughout the surveillance period. These findings suggest that domestic ducks in southern China mediate the interaction of viruses between different gene pools and facilitate the generation of novel influenza virus variants circulating in poultry.
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Ye, Yuanjun, Haiping Fu, Yiwei Zhou, Shanxin Zhang, Zehuang Wang, Lihua Tian, Jianjun Tan, Genfa Zhu, Jinmei Liu, and Yechun Xu. "Establishment of DNA Molecular Fingerprint of Caladium Core Collections." Agriculture 13, no. 1 (January 13, 2023): 200. http://dx.doi.org/10.3390/agriculture13010200.
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Caladiums are promising colorful foliage plants due to their unique leaf shapes and dazzling colors. Until now, over 2000 varieties of Caladium have been cultivated worldwide. The long-term natural variation and artificial selection have enriched the germplasm resources of Caladium in the market, yet have blurred its genetic background. In this study, 16 informative EST-SSR markers were used to screen 144 Caladium accessions, indicating that 16 EST-SSRs could distinguish all genotypes with a minimum cumulative identity probability (PI) of 2.0 2 × 10−15. Using the simulated annealing method, the richest genetic information was acquired at the same compression ratio. A final core of 44 accessions was selected, comprising 30.6% of the individuals and retraining more than 95% of the total genetic information. No significant differences were observed in allele frequency distributions or genetic diversity parameters between the core collection and the entire population. Cluster analysis roughly divided the core collections into four populations, where 66.7% of the private alleles were detected in Pop2. Finally, DNA molecular fingerprints of 44 core accessions were established, including barcodes and quick response (QR) code molecular identities (ID). The results will lay a theoretical foundation for identifying, preserving, and utilizing Caladium germplasm resources.
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Baudouin, Emmanuel, Juliette Puyaubert, and Christophe Bailly. "Physiological and Environmental Regulation of Seed Germination: From Signaling Events to Molecular Responses." International Journal of Molecular Sciences 23, no. 9 (April 27, 2022): 4839. http://dx.doi.org/10.3390/ijms23094839.
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Shynkarenko, Viktor, and Inna Demidovich. "CONSTRUCTIVE-SYNTHESIZING MODELING OF NATURAL LANGUAGE TEXTS." Computer systems and information technologies, no. 3 (September 29, 2023): 81–91. http://dx.doi.org/10.31891/csit-2023-3-10.
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Means for solving the problem of establishing the natural language texts authorship were developed. Theoretical tools consist of a constructors set was developed on the basis of structural and production modeling. These constructors are presented in this work. Some results of experimental studies based on this approach have been published in previous works by the author, the main results should be published in the next ones.
Constructors developed: converter of natural language text into tagged, tagged text into a formal stochastic grammar and the authors style similarity degree establishment of two natural language works based on the coincidence of the corresponding stochastic grammars (their substitution rules).
The proposed approach makes it possible to highlight the semantic features of the author's phrases construction, which is a characteristic of his speech. Working with a sentence as a unit of text to analyze its construction will allow you to more accurately determine the author's style in terms of the use of words, their sequences and characteristic language constructions. Allows not to be attached to specific parts of speech, but reveals the general logic of building phrases.
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Hammond, Darcy H., Eva K. Strand, Penelope Morgan, Andrew T. Hudak, and Beth A. Newingham. "Environmental Influences on Density and Height Growth of Natural Ponderosa Pine Regeneration following Wildfires." Fire 4, no. 4 (October 21, 2021): 80. http://dx.doi.org/10.3390/fire4040080.
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Over the past century the size and severity of wildfires, as well as post-fire recovery processes (e.g., seedling establishment), have been altered from historical levels due to management policies and changing climate. Tree seedling establishment and growth drive future overstory tree dynamics after wildfire. Post-fire tree regeneration can be highly variable depending on burn severity, pre-fire forest condition, tree regeneration strategies, and climate; however, few studies have examined how different abiotic and biotic factors impact seedling density and growth and the interactions among those factors. We measured seedling density and height growth in the period 2015–2016 on three wildfires that burned in ponderosa pine (Pinus ponderosa) forests in the period 2000–2007 across broad environmental and burn severity gradients. Using a non-parametric multiplicative regression model, we found that downed woody fuel load, duff depth, and fall precipitation best explained variation in seedling density, while the distance to nearest seed tree, a soil productivity index, duff depth, and spring precipitation as snow best explained seedling height growth. Overall, results highlight the importance of burn severity and post-fire climate in tree regeneration, although the primary factors influencing seedling density and height growth vary. Drier conditions and changes to precipitation seasonality have the potential to influence tree establishment, survival, and growth in post-fire environments, which could lead to significant impacts for long-term forest recovery.
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Quinn, Lauren D., and Jodie S. Holt. "Restoration for Resistance to Invasion by Giant Reed (Arundo donax)." Invasive Plant Science and Management 2, no. 4 (October 2009): 279–91. http://dx.doi.org/10.1614/ipsm-09-001.1.
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AbstractThe relationship between plant community composition and invasibility has been studied extensively but seldom in the context of ecosystem restoration. Experimental riparian restoration plots differing in species composition and density were established and evaluated for susceptibility to invasion by giant reed, a common riparian invader in California, and natural recruitment by riparian species over time. Plots were planted in 2002 with cuttings of common threesquare (a sedge), seepwillow (a shrub), and Goodding's willow (a tree) at two densities in monoculture and all possible mixture combinations. Giant reed rhizomes were introduced into half of the plots in the spring of 2003, while the remaining plots were allowed to undergo natural recruitment for an additional year. In late winter 2004, giant reed rhizomes were planted in the remaining plots. Both planting groups were followed for one growing season to evaluate giant reed establishment, survival, and growth. Community composition affected giant reed performance, particularly in 2003 before natural recruitment occurred. In that year, plots containing seepwillow + willow had the lowest giant reed shoot production, growth, and survival. All plots containing seepwillow were resistant to colonization by natural recruitment in 2004, but none of the planting treatments affected giant reed success in that year. Giant reed was more successful overall in 2004 despite deeper shade and drier soils. This pattern could be attributed to larger initial rhizome size in 2004, which allowed giant reed to overcome environmental stress during establishment. Planting density did not impact giant reed or natural recruitment independently, but may affect environmental parameters and warrants further study as a potential contributor to restoration success. Our results indicate that choice of species composition in restoration might impact giant reed invasion success initially, but community resistance might not be sustainable and maintenance-free over time.
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Ali, Hamada E., and Solveig Franziska Bucher. "Ecological Impacts of Megaprojects: Species Succession and Functional Composition." Plants 10, no. 11 (November 9, 2021): 2411. http://dx.doi.org/10.3390/plants10112411.
Full textAbstract:
Land-use changes have huge impacts on natural vegetation, especially megaprojects, as the vegetation layer is destroyed in the course of construction works affecting the plant community composition and functionality. This large-scale disturbance might be a gateway for the establishment of invasive plant species, which can outcompete the natural flora. In contrast, species occurring in the area before the construction are not able to re-establish. In this study, we analyzed the impact of a pipeline construction on a wetland nature reserve located in northern Egypt. Therefore, we analyzed the plant species occurrence and abundance and measured each plant species’ traits before the construction in 2017 as well as on multiple occasions up to 2 years after the construction had finished on altogether five sampling events. We found that the construction activity led to the establishment of an invasive species which previously did not occur in the area, namely, Imperata cylindrica, whereas five species (Ipomoea carnea, Pluchea dioscoridis, Polygonum equisetiforme, Tamarix nilotica, and Typha domingensis) could not re-establish after the disturbance. The functionality of ecosystems assessed via the analysis of plant functional traits (plant height, specific leaf area, and leaf dry matter content) changed within species over all sampling events and within the community showing a tendency to approximate pre-construction values. Functional dispersion and Rao’s quadratic diversity were higher after the megaproject than before. These findings are important to capture possible re-establishment and recovery of natural vegetation after construction and raise awareness to the impact of megaprojects, especially in areas which are high priority for conservation.
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Rahe, Paul A. "MONTESQUIEU'S NATURAL RIGHTS CONSTITUTIONALISM." Social Philosophy and Policy 29, no. 2 (July 2012): 51–81. http://dx.doi.org/10.1017/s0265052512000027.
Full textAbstract:
AbstractWhen Woodrow Wilson, in the course of his campaign for the Presidency in 1912, attacked Thomas Jefferson and Charles-Louis de Secondat, baron de La Brède et de Montesquieu, he knew what he was about—for the constitutionalism articulated by the latter and embraced, in turn, by the Framers of the American Constitution was a systematic attempt to put into practice something very much like the first principles spelled out in the Declaration of Independence. Montesquieu was not a doctrinaire. He feared that, in his own country and elsewhere, revolution would eventuate in the establishment of a despotism, and so he gently, quietly promoted unobtrusive reform. But the cautious, prudential political science that he outlined in his Spirit of Laws was anything but value-free. If the American framers found his legislative science of use, it was because the hatred of despotism and love for liberty animating its author was grounded in an account of natural right closely akin to the one, espoused in John Locke’s Two Treatises of Government, that had inspired their revolution.