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Wuhu suburban farmland soil pollution on soil animal community structure of

Author: ZhuYongHeng
Tutor: WangZongYing
School: Anhui Normal University
Course: Physical Geography
Keywords: Heavy metal pollution Herbicide Soil fauna Wuhu City
CLC: X833
Type: Master's thesis
Year: 2002
Downloads: 237
Quote: 1
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Abstract

The use of ecological theory and method Wuhu suburb contaminated soil animal community structure were analyzed. The results show that both are heavy metal pollution or contamination of soil animals herbicides constitute a hazard. Heavy Metal Pollution on Soil Animal Community Structure: In the heavy metal pollution of farmland six plots were obtained in 26 categories of 3775 soil animals, sub-scribe to six 10 classes, dominant groups wired insects, Collembola and mites three class, common groups nine categories, 14 categories of rare taxa. The composition of soil fauna and quantity with the severity of pollution reduction, soil density of animals have the same trend, especially small and medium soil animals, there is a greater number of dominant groups ebb and flow of common and rare taxa taxon composition gradually reduced. Diversity studies show that H and heavy metal pollution of the relationship between the effects of the season because of being complicated, more stable environment in winter and early summer, serious pollution of soil animal community structure plots affected by heavy metals, reducing the number of dominant groups, community E increases C decreases, H higher; while the spring in a transition phase, some groups (such as mites) the number of outbreaks increased community C, H is small; density of soil fauna community groups and multi-index DG diversity index compared with the pollution DIC aggravation reduced. Soil contaminated by heavy metals animals Table cohesion weakened, or even inverse distribution phenomenon. Heavy metal pollution soil fauna community similarity is high, in particular the formation of similarity (Jaccard similarity coefficient greater than 0.5 All), with different levels of heavy metal contamination of soil fauna Motyka similarity coefficient is lower. Different types of contamination of soil fauna plot number from winter to spring to early summer gradually increased, the number of individuals most in spring, winter, at least, early summer centered; diversity H are in May (early summer) the highest plots in serious pollution lowest in March, while the less contaminated plots in December lowest; D · G and DIC indices are lowest in December, in seriously polluted plots in May highest in the less contaminated plots in March the highest. Heavy metal pollution of farmland in heavier soil animals and soil organic matter content is not positively correlated, because heavy metal contamination of the soil structure deterioration in serious pollution of soil bulk density larger sample, thus affecting workers soil animals survive and multiply, causing soil animals reduce the quantity and composition, community structure simplification. Herbicide contamination on soil animal community structure: the spraying of herbicides and soil fauna number of individuals of a significant change. The day after the number of individuals applying herbicides drastically reduced, but the number is slightly recovered after ten days; herbicide group number in one day and ten days later continued to decline. Dominant groups nematode resilience herbicide contamination than Collembola strong, the day after herbicide drastically reduced the number of nematodes, ten days after the number has been restored, while continuing to reduce the number of Collembola; overall advantage taxa dominance in the herbicide down after a day, ten days after a slight increase. Soil fauna diversity index H after a day in the herbicide increased after ten days decreased significantly positively correlated with E, and C were negatively correlated; D · G and DIC index trend is not applied herbicide community> herbicide Next Day> herbicide after ten days. Community similarity analysis showed that community composition similarity (Jaccard similarity) to herbicides and herbicide is not applied ten days after the two smallest communities, and reflects the herbicide pollution on soil composition and the number of animals affected Motyka similarity coefficients After two maximum community pollution, contamination with herbicides were not contaminated and just two minimum similarity between communities. Spraying of herbicides also make a table cohesive soil animals weakened, particularly evident in the performance of the dominant groups. Research Progress on Soil Zoology: In a lot of reading on the basis of previous literature, summed up the characteristics of the soil Zoological Research: ① in the regional distribution concentrated in eastern China, ② study diverse ecosystem types, ③ a variety of angles diverse, ④ applied research is developing rapidly. And pointed out some of the soil Zoological Research blank area. Then separately from the point of view of ecology and resource summarizes the results of the research of soil zoology. On this basis, that the soil to be developed in a number of zoological research areas: ① global change on soil fauna and Response, ② Chinese characteristics and ecological zone type of research, ③ land cover / land use change on soil fauna research, ④ basic research, ⑤ soil animal diversity and its conservation research, ⑥ soil fauna in the soil ecosystem and terrestrial ecosystem nutrient cycling and energy flow in the role of.

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CLC: > Environmental science, safety science > Environmental Quality Assessment and Environmental Monitoring > Environmental monitoring > Soil monitoring
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