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31.
Muhammad Yaseen Muhammad Zahir Aziz Abdul Aleem Jafar Muhammad Naveed 《International journal of phytoremediation》2016,18(5):502-508
A field experiment in collaboration with a private textile industry (Noor Fatima Fabrics Private (Ltd.), Faisalabad) was conducted to evaluate the effect of disposed water from bleaching unit, printing unit and end drain for improving growth and yield of wheat under saline sodic soil. Textile waste water along with canal water (control) was applied with and without liquid NPK fertilizer. The application of liquid NPK fertilizer with end drain waste water increased plant height, spike length, flag leaf length, root length, number of tillers (m?2), number of fertile tillers (m?2), 1000 grain weight, grain yield, straw yield and biological yield up to 21, 20, 20, 44, 17, 20, 14, 44, 40 and 41%, respectively compared to canal water (control). Similarly, the NPK uptake in grain was increased up to 15, 30 and 28%, respectively by liquid fertilizer treated end drain water as compare to canal water with liquid fertilizer. Moreover, concentration of different heavy metals particularly Cu, Cr, Pb and Cd was decreased in grains by application of waste water along with liquid NPK. The result may imply that waste water application along with liquid-NPK could be a novel approach for improving growth and yield of wheat in saline sodic soils. 相似文献
32.
33.
E. Cortés A.A. Kirk J.A. Goolsby P.J. Moran A.E. Racelis M.A. Marcos-García 《Biocontrol Science and Technology》2011,21(11):1369-1373
Arundo donax L. (Poaceae) is native to Mediterranean Europe and invasive in the Rio Grande Basin of North America. Rhizomes from nine sites in France and Spain infested with a candidate control agent, the armoured scale Rhizaspidiotus donacis (Hemiptera: Diaspididae) weighed 50% less than those from nine sites without scale. 相似文献
34.
Jan Dirk van Elsas Alexander V Semenov Rodrigo Costa Jack T Trevors 《The ISME journal》2011,5(2):367-183
In this review, our current understanding of the species Escherichia coli and its persistence in the open environment is examined. E. coli consists of six different subgroups, which are separable by genomic analyses. Strains within each subgroup occupy various ecological niches, and can be broadly characterized by either commensalistic or different pathogenic behaviour. In relevant cases, genomic islands can be pinpointed that underpin the behaviour. Thus, genomic islands of, on the one hand, broad environmental significance, and, on the other hand, virulence, are highlighted in the context of E. coli survival in its niches. A focus is further placed on experimental studies on the survival of the different types of E. coli in soil, manure and water. Overall, the data suggest that E. coli can persist, for varying periods of time, in such terrestrial and aquatic habitats. In particular, the considerable persistence of the pathogenic E. coli O157:H7 is of importance, as its acid tolerance may be expected to confer a fitness asset in the more acidic environments. In this context, the extent to which E. coli interacts with its human/animal host and the organism''s survivability in natural environments are compared. In addition, the effect of the diversity and community structure of the indigenous microbiota on the fate of invading E. coli populations in the open environment is discussed. Such a relationship is of importance to our knowledge of both public and environmental health. 相似文献
35.
J. D. Smolik 《Journal of nematology》1982,14(4):585-588
Tylenchorhynchus robustoides reduced (P = 0.05) growth of Agropyron smithii (western wheatgrass) at soil temperatures of 20, 25, 30, and 35 C. Growth reduction increased with increasing soil temperatures. Highest populations of T. robustoides were recovered at 25 and 30 C. Clipping weights of Buchloe dactyloides (buffalo grass) were reduced at 25 and 30 C; however, root/crown weights were reduced at 15, 20, 30, and 35 C in nematode infested vs. noninfested soil. Reproduction of T. robustoides was greater at 25, 30, and 35 C than at 20 C on B. dactyloides. In a greenhouse study, T. robustoides reduced clipping and root/crown weights of both grasses 24-64%. 相似文献
36.
To predict the growth and spread of an insect population introduced for the biological control of weeds, one must first understand the factors affecting the movement of individuals in the population. The purpose of this study was to determine how the dispersal rate of Aphthona lacertosa (Rosenhauer) (Chrysomelidae) was affected by conspecific density and by the characteristics of leafy spurge (Euphorbia esula L.: Euphorbiaceae) in patches where these beetles feed. In 2002 in Manitoba and in 2003 in Alberta, Canada, between 200 and 2500 insects were released in small patches (<10 m2) of spurge. The number and location of beetles within patches was monitored over subsequent days. In 1 m2 plots within patches, spurge ramet density, the proportions of vegetative and reproductive ramets, and ramet height were measured. In both years, beetle movement within patches and emigration from patches, was not affected by conspecific density. In Manitoba in 2002, beetles aggregated non-randomly on either vegetative or reproductive ramets within plots, but plot characteristics were not related to the formation of aggregations. In Alberta in 2003, plots in which beetles aggregated had significantly higher spurge density but did not differ in either the proportion of vegetative ramets or in the amount of non-spurge vegetation. These results suggest that density-dependent dispersal does not limit the population's ability to reach densities up to 2500 beetles/m2. 相似文献
37.
Shota Nishijima Hiroshi Kubota Toshiki Kaga Suguru Okamoto Hisae Miyahara Hiroshi Okamura 《Population Ecology》2021,63(1):27-40
Regime shifts of climatic and environmental conditions potentially affect the productivity of fishery resources, posing challenges in stock management. The stocks of the Japanese flying squid (Todarodes pacificus) are suspected to suffer from regime shifts, but detecting the occurrence of regime shifts in this species is generally difficult and unreliable because the short-lived nature of this species inherently confounds the effect of regime shifts with observation and process errors. Here we developed a new state-space assessment model to evaluate the influence of regime shifts on the spawner-recruit relationship of the Japanese flying squid. The model simultaneously estimates the population dynamics of multiple stocks that could share some life history parameters, thereby stabilizing parameter inference. We demonstrate that two regime shifts in productivity around 1991 and 2015 caused two- to threefold changes of maximum sustainable yields. The model with regime shifts clarifies the relationship between fishing pressure and spawner abundance that is difficult to detect in a model with no regime shift. The state-space approach is a promising tool for accurately assessing stock status by separating the recruitment process from observation errors and is expected to contribute to the effective management of marine biological resources sensitive to regime shifts. 相似文献
38.
为了揭示退化高寒草甸逆向转变的驱动因子,通过野外调查和室内分析相结合的方法探究了黄河源不同修复措施(施有机肥F、免耕补播N、施有机肥+免耕补播FN)处理高寒草甸植物群落特征、土壤理化性质和两者相关性的变化规律,阐明不同修复措施对黄河源退化高寒草甸植物群落与土壤养分的影响。结果表明:免耕补播显著增加草甸物种丰富度指数(P<0.05);施有机肥+免耕补播显著增加草甸植物盖度、总生物量、Shannon Wiener多样性指数和Pielous均匀度指数(P<0.05)。不同人工修复后草甸植物功能群地上、地下生物量变化趋势基本一致(除豆科)。和对照相比,莎草科,杂类草地上和地下生物量含量在N、FN处理分别降低83.04%、73.86%、30.43%、92.37%和96.51%、84.09%、85.68%、95.36%;禾本科地上和地下生物量含量在F、N和FN处理分别增加7.29%、23.45%、17.93%和6.04%、4.03%、10.52%;豆科地上生物量含量基本保持不变,地下生物量含量在F、N和FN处理分别降低24.43%、82.19%和42.61%。F显著增加土壤有机碳含量(P=0.033);N显著降低土壤NO3--N含量(P=0.009);FN显著降低土壤pH和增加土壤速效磷含量(P=0.024);F和FN显著增加土壤含水量(P=0.000),N则显著降低土壤含水量(P=0.000);F显著降低土壤容重(P=0.018)。相关性分析表明植物Shannon Wiener多样性和Pielous均匀度与土壤速效磷含量呈显著正相关(P=0.037;P=0.033),土壤有机碳和含水量与总生物量呈显著正相关(P=0.027;P=0.032),pH与盖度呈显著负相关(P=0.049)。冗余度分析结果表明土壤有机碳含量和含水量显著影响了植物群落结构特征,解释率分别为30.3%和19.7%。研究结果表明,因地制宜进行退化高寒草甸施有机肥+免耕补播修复措施,能够明显提高草地生产力,改善草甸植物群落及其土壤养分和水分环境。 相似文献
39.
N-糖蛋白去糖基化酶(PNGase)是一种广泛存在于真菌、植物、哺乳动物中的去糖基化酶,可以水解N-糖蛋白或 N-糖肽上天冬酰胺与寡糖链连接的化学键,并释放出完整的N-寡糖。PNGase在生物体内参与蛋白质降解、器官发育、个体生长等过程。人PNGase基因功能缺陷会导致先天性去糖基化障碍,小鼠PNGase缺陷会导致胚胎致死性,线虫PNGase缺陷使其寿命下降。本文对PNGase在不同物种的分布、蛋白质结构、酶学功能及生物学功能进行阐述,为PNGase的生理病理功能及致病机制的基础研究提供思路,为PNGase作为糖生物学工具酶或药物开发的创新应用研究奠定基础。 相似文献
40.
M.F. Amaral J.M.R. Aranha M.S. Menezes 《Studies on Neotropical Fauna and Environment》2013,48(2):106-110
In the subtropical Atlantic rain forest of southern Brazil, reproduction of the catfish Pimelodella pappenheimi was studied over a two years period in a small coastal stream representing a widely undisturbed aquatic habitat. According to analyses of the gonad status, reproduction is mainly seasonal with a peak in the rainy summer months, consisting of multiple spawning. The average body length of the fishes attaining sexual maturity was the same in both sexes. At the study site summer storms cause flash floods, and heavy rainfalls can suddenly increase the river flow. Reproductive females were found to burrow in the clay palisades of the river sediments which is regarded a behavioural adaptation protecting the offspring from being washed away. 相似文献