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951.
952.
R. M. LOEWY L. G. CARVAJAL M. NOVELLI A. M. PECHEN DE D'ANGELO 《Journal of environmental science and health. Part. B》2013,48(6):869-881
Groundwater samples were collected from monitoring wells along an area of intensive fruit production. Different types of correlations were investigated between soil physicochemical characteristics, depths and agricultural practices with pesticide detection frequency. In the three analyzed periods azinphos methyl, S-(3,4-diydro-4-oxobenzo[d]-[1,2,3]-triazin-3-ylmethyl)-O,O-dimethyl phosphorodithioate, showed a definite seasonal behavior related to the application pattern, increasing its concentration in the aquifer from October to November-December and then decreasing towards March. Samples obtained during the non-spraying season showed that azinphos methyl residues were lower than detection limit (LOD). An inverse correlation was observed between azinphos methyl concentration and the time elapsed since the last pesticide application. Seasonal events such as rain and irrigation influence the chemical concentration in the well, while no correlation was obtained between soil characteristics and azinphos methyl concentration. The soil attenuation capacity was not enough to prevent the presence of azinphos methyl in the aquifer during the application season. 相似文献
953.
954.
955.
企业环境污染与政府控制监控 总被引:1,自引:0,他引:1
从政府监控的角度,采用博弈论的方法对企业环境污染的行为进行了分析。根据模型的不同假设前提,构造了单阶段和多阶段的博弈模型,得出博弈双方的均衡战略,以及某些关键因素(如政府对企业的惩罚系数及监督成本,企业环境污染行为的收益等)对博弈双方的影响,提出了减少企业污染行为发生的建议。 相似文献
956.
Halictine bees exhibit a wide range of social behaviour that varies both inter- and intraspecifically. Although previous studies
suggested that the intraspecific variation might be attributed to temperature differences, there was no direct evidence to
detect the relationships between temperature and socialities. Lasioglossum (Evylaeus) baleicum exhibited solitary behaviour in a cooler locality (Kawakita) because of the shorter breeding season; in a warmer locality
(Nishioka Park), however, this bee species exhibited eusociality at sunny site and solitary behaviour at shady site, whereas
a molecular phylogeny confirms that all of these colonies are evidently conspecific. Therefore, we examined the effect of
degree-day accumulation on the sympatric social variation of L. baleicum by rearing the bees to calculate the threshold temperature. Whereas they showed high mortality, the threshold temperature
was estimated to be 10.33°C and the expected degree-day accumulation was 340 degree days. When we use this value of a degree-day
accumulation to estimate the expected eclosion date, the estimated dates were always consistent with observed eclosion dates.
In any sites where the bees were solitary, the degree-day accumulation was not enough for the second eclosion by the end of
the bee-active season. In Nishioka Park, sex ratio of the first brood was female biased, and daughters were smaller than mothers;
in Kawakita, however, there was no sex bias, and daughters were as large as their mothers indicating that the foundresses
seem to produce gyne-sized females in Kawakita but worker-sized females in Nishioka though these females do not become workers
at shady site. 相似文献
957.
The HOMINIDS ABM is a new Agent Based Model that simulates the actions of two species of proto-human agents defined by a few, simple parameters. These proto-human agents attempt to subsist by foraging and nesting on dynamic, spatially explicit landscapes. The landscapes are described with a number of parameters based on empirical field data collected in habitats in East Africa. The results of three separate scenarios with 1 year model runs repeated 30 times each, for a total of 90 simulations, are presented and discussed to illustrate both the capacity and flexibility of our ABM modeling environment. The simulations show that the model food preferences and anatomy ascribed to Australopithecus boisei resulted in different expressions of foraging behaviors and subsistence strategies in two distinct ecological settings, and that adding tubers to the diet significantly increases the chances of the hominid agents meeting their daily caloric requirements year-round. In addition, this paper provides links to the open-source implementation code, along with the user documentation, design document, java API, and all datasets required to replicate the simulations. 相似文献
958.
Han Mei Zhou Baohua Yang Peilin Gao Guiqin & Zhang Weiying . Department of Geography Shandong Normal University Jinan China . Department of Geography Jinan University Jinan China 《中国人口.资源与环境(英文版)》2005,(4)
1INTRODUCTIONAncient lakes are lakes that once existed in history,butnow have died out.As a kind of land water and geomorphicconfiguration,the formation and evolution of ancientlakes were closely linked with the variance of geographicenvironment.The south coast plain of Laizhou Bay is aplain extending from the estuary of the Xiaoqing Riverin the west to the estuary of the Jiaolai River in the east.There were once some lakes on the plain in history,suchas Judian Lake,Qingshuibo Lake,an… 相似文献
959.
S. Ostojić M. Pavlović M. Živić Z. Filipović S. Gorjanović S. Hranisavljević M. Dojčinović 《Environmental Chemistry Letters》2005,3(1):29-32
An investigation carried out in 11 dairies in Serbia has shows that 78.75 % of whey, a by-product of cheese industry, is emitted into river systems, thus contributing to the organic pollution of the environment. This pollution can be avoided by processing of whey into food and pharmaceuticals. It is shown that low-temperature regime of whey concentration and fractionation, based on vacuum concentration and diafiltration, preserves whey proteins undenaturated, as proved by differential scanning calorimetry method. Functional native whey proteins based food products, with potentially high immunomodulatory activity, are obtained. 相似文献
960.
从生态位到可持续发展位:概念的演进 总被引:3,自引:0,他引:3
庄悦群 《中国人口.资源与环境》2005,15(4):1-4
生态位概念是生态学的一大基石,它主要有基础生态位、实际生态位和多维生态位三个基本概念。而由生态位概念发展来的生态位理论则是生态学的支柱。由于生态位概念揭示的是生态个体、种群和物种生存与竞争的普遍规律。因此。20世纪80年代以来。它开始被引入社会科学研究的领域。成为研究人类社会巨系统中的一个分析工具。由此也有了从生态位到发展位。再到可持续发展位的演进。由生态位概念发展而来的基于可持续发展理论的可持续发展位概念,是我们研究全球可持续发展体系的一个重要视角。由于构成可持续发展位的可持续发展因子的集合不同,形成了不同的“可持续发展位。概念,主要有可持续发展基本位,可持续发展理想位,可持续发展优势位和可持续发展关键位,它们共同成为“可持续发展位”的不同一性。 相似文献