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This review describes the toxic effects of agrochemicals on earthworms. Carbamates are described as extremely toxic to earthworms in comparison to organophosphorus insecticides. Some pesticides have drastic effect on the nervous system of the earthworm. Earthworm can accumulate heavy metals from the soil in higher levels than any other animal. Mercury is twenty times more toxic than chromium.  相似文献   
2.
Although half of the administrative units in China are said to have implemented their local Agenda 21, the promotion of sustainable communities is not pervasive. In this paper, we adopted a relatively untried mode of analysis and a socio-economic context to illustrate the potentials and failures of China's grassroots local government bodies in achieving sustainable waste management. Our study shows that, among the three main functions of sustainable waste management (ensuring environmental hygiene, provision of recycling logistics and changing the consumption pattern of the local community) for local governments, grassroots local government bodies in mainland China are only able to do the minimum, i.e. ensuring environmental hygiene and handling complaints. One of the reasons for the failure is that, despite the emphasis on capacity building in China's Agenda 21, the reality is that no action is taken to empower grassroots local government. Despite the high profile accorded by the Chinese central government to motivating local governments to formulate their own Agenda 21, local sustainability and waste management performance have little relevance to the appraisal systems of these government agents.  相似文献   
3.
Very few studies have considered the residual effect of inorganic and organic fertilisation on oxisol chemistry and plant productivity while studying the response of maize to fresh fertiliser application. The purpose of the present study was to examine the effects of five treatments of inorganic and organic fertilisers on maize productivity and soil fertility under field conditions in a Savannah region. The trials were conducted from 2009 to 2011 and the treatments included inorganic nitrogen–phosphorus (NP), Entada abyssinica, Tithonia diversifolia, inorganic NP combined with E. abyssinica, and inorganic NP combined with T. diversifolia, and no fertilised plots. The combination of NP with T. diversifolia or E. abyssinica leaves resulted in the highest increase in grain yields during the first crop season.The positive residual effects of fertilisers on maize grain yield were strong and significant in the immediate succeeding season and decreased during the second year following fertilisation. The highest residual effect was observed in plots fertilised with E. abyssinica combined with NP, followed by T. diversifolia combined with NP, and E. abyssinica and T. diversifolia without NP, respectively. The lowest residual effect was observed in plots fertilised with inorganic NP. Analytical results revealed that total nutrients in the soil matrix are not dominantly in forms available for plant uptake. There were significant residual effects for total potassium in the site with low initial nutrient levels. The soil content of bioavailable phosphorus, nickel, zinc, copper, and cobalt was in general below detectable levels.  相似文献   
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As nematodes are widespread throughout the terrestrial ecosystem, and have shown potential to be used as indicators of ecosystem development. Nematode indices were used to distinguish between two different amendment types during platinum mine tailing reclamation. The two different amendment types include the use of woodchip-vermicompost and inorganic fertiliser. Both treatments had a higher number of nematodes than the natural veldt. Of the 17 genera identified, Rhabditis dominated in all sites. A significant difference (ANOVA; p < 0.05) was observed between Plant parasitic indices of both treatments and the natural veldt. The main decomposition pathway was dominated by bacterial decomposition for all sites as evident from the Channel index values. The dominance of bacterial feeding nematodes and the high number of nematodes feeding on higher plants indicate that the platinum mine tailings sites may be in an initial stage of succession. It is expected that the woodchip-vermicompost may have a low C:N ratio, causing the system to be nutrient enriched as indicated by the enrichment index. An increase in food-web development was observed in the woodchip-vermicompost sites indicating recovery from disturbance, during the third sampling period.  相似文献   
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