| Bordeaux nutritional protective powder (BNPP) is a kind of dry suspending agent, which is based on the effective element rate of Bordeaux mixture, added with additives and assistant materials, then concentrated and refined. Because of the trace element added in the preparation, it could provide nutrition to the crops. Moreover, the preparation could stick to plant surface for a long time, so that it could enhance the effects on preventing and curing germina, reduce the quantity and time of spray, and have other advantages in the manufacturing, applying and storing procedures. Bordeaux nutritional protective powder could be equal even exceed to congeneric product in the word. Furthermore, the maturely productive technique made it be volume-produced, so Bordeaux nutritional protective powder in farming widely use will come true. However, as the effective component of Bordeaux nutritional protective powder—copper applied frequently, the cumulation of copper in soil must be keep track to study the influence of copper on soil property and crop growth.In order to offer academic thereunder for producing, spreading and ecosecurity estimation of Bordeaux nutritional protective powder, several experiments were conducted and sequential extractive method and biostatistical method were used in this study. The vertical transferance, fraction transformation and desorption characterisitcs of copper in soil treated with Bordeaux nutritional protective powder were examined by column simulation, desorption experiment, laboratory incubation. Also, the effects of BNPP on seed germination, growth and development of plants and so on were studied by acute toxicity and pot experiment. The biologic activity index of the soil contamination by Bordeaux nutritional protective powder and other copper agents was definituded. The main results were summarized as follows:(1) Copper, the effective component of BNPP mainly accumulated in top soil after leaching by pH 7.0 and 4.0 leaching water, the upright down transference of copper was small and could not contaminate the groundwater. The moving of copper was accelerated with the increasing of organic materiel and acidity of leaching water, especially leaching by pH 2.0 simulated acid rain. The copper migrating in the soil column was mainly in exchangeable form. The greatest migratory speed and extent was found in CS treatment, which could move to 10-15cm in soil column; copper was mainly accumulated in 7-10cm soil layers in BNPP and KCD treatments. However,soil in the bottom of soil column was not polluted by copper.(2) The desorption rate of Cu2+ from soils treated by three copper-based pesticides increased with increase of concentration of oxalic acid and citric acid, especially of citric acid. The higher temperature was in organic acid desorption solution (except in citric acid), the higher desorption rate of Cu2+ was found in soil. As pH value of desorption solutions increased, Cu2+ desorption rate decreased as oxalic acid was added into soil; in contrast, when citric acid was added into the tested soil, Cu2+ desorption rate decreased at first, then enhanced, and then decreased again, showing as of lying"S". Furthermore, Cu2+ desorption in the calcareous Fluvo-aquic soil (Och-Aquic Cambosols) was higher than in the Brown soil (Hap-Udic Luvisols), so the effectivity and transference of Cu2+ in the former was less than the latter. Taking all the experiment conditions into account, the Cu2+ desorption rate for three copper-based pesticides soil was CS>KCD>BNPP, and thus soil environment was least effected by BNPP.(3) The best model to describe Cu2+ desorption kinetics in BNPP treated soil was two-constant equations, followed by the Elovich equation. Cu2+ desorption rate from copper-based pesticides treated soil was desorpted so fast that the desorption equilibrium could be reached only after 60 min desorption. Comparing with oxalic acid, desorption rate was greater when citric acid was used. And the least Cu2+ initial desorption rate was found in BNPP treated soil.(4) The application of BNPP significantly increased the ratio of MnOX-Cu and NFe-Cu in the Brown soil (Hap-Udic Luvisols), and the ratio of FeMnOX-Cu in the calcareous Fluvo-aquic soil (Och-Aquic Cambosols). The ratio of EX-Cu in both two kinds of soil treated with BNPP was significantly less than that of CS and KCD. In the incubation, EX-Cu, OR-Cu, MnOX-Cu and NFe-Cu were increased; FeOX-Cu and Res-Cu were increased first then decreased in the Brown soil (Hap-Udic Luvisols). However, the invert extent of copper conformation in the calcareous Fluvo-aquic soil (Och-Aquic Cambosols)was small, EX-Cu, Car-Cu and Res-Cu were decreased, FeMnOX-Cu and OR-Cu were increased, and the transformation of copper reached equilibrium in fourteen days after incubation.(5) The activities of urease, sucrase, acdic phosphatas and the SMBC were irreversibly inhibited by BNPP and the inhibitions were increased with the increasing BNPP dosage. And statistical analysis indicated that there was great remarkable negative relationship between the biological activity and copper content. It was feasible to use them mentioned above as biological index to evaluate BNPP polluted soil. Taking phosphatase as warning index, the threshold value of warning of first-class soil was 19.26%, that of second-class soil was 22.04% in Brown soil; there were 7.02% and 30.11% in Fluvo-aquic soil, respectively.(6) The relationship between copper chemical conformation and biological index in soil treated with BNPP was primarily proved up. In the Brown soil (Hap-Udic Luvisols), the more contributions to inhibiting effect of soil enzymatic activities and SMBC were OR-Cu and EX-Cu; MnOX-Cu, NFe-Cu and FeOX-Cu also had some effects. OR-Cu, EX-Cu and FeMnOX-Cu played an important role in biological index of the calcareous Fluvo-aquic soil (Och-Aquic Cambosols), especially the former. In order to weight the contamination degree of BNPP in both soils, OR-Cu and EX-Cu should be taken into account.(7) In the soil incubation experiment, BNPP made similar effects with CS on soil biological property. Even, some enzyme activity in BNPP were less than CS, these results might attribute to the additives in BNPP. However, the inhibition of additives was reduced in soil with plant growth, and the effects of BNPP on soil biological properties were less than that of CS. But the effects of BNPP on soil biological were still higher than that of KCD not only in soil with plant but also in soil without plant. Therefore, in order to improve the effect of BNPP on soil biological properties, the kinds and dosage proportion of additives should be taken into account.(8) Copper inevitably accumulated in soil for the long term application of BNPP and other copper agents, but the availability of copper in the soil was less than KCD and CS. Furthermore, the availability of zinc in soil was increased; this might contribute to zinc which added in the product. But, soil available iron was significantly decreased for the higher content of copper in the soil even if iron added in the produc. The application of organic matter could reduce the availability of the calcareous Fluvo-aquic soil (Och-Aquic Cambosols) copper, and increase the content of available zinc and iron. (9) The inhibitory effects of BNNP and KCD on the plant seed germination were lower than that of CS, this might be related to their low copper solubility. And the copper concentrations of BNNP and KCD which caused the same inhibitory rate of plant seed germination were 2-4 times than that of CS. So the characteristics of copper-based pesticides should be taken into account as evaluating those effects on the environment. The toxic responses of plants for the copper-based pesticides were significantly different, and the plant sensitive sequence order was cole>tomato>wheat. It was feasible to use cole as indicatory plant to be toxicological diagnosis of soil contaminated with copper-based pesticides.(10) The germination index and root elongation were the most sensitive to copper-based pesticides pollution, and they were significantly related with the copper concentration for logarithmic expression or quadratic polynomial expression. So germination index and root elongation could be applied in the research on the dose-response relationship between pollution toxicity of copper-based pesticides and plant response. In this research, the threshold copper concentration which inhibited the germination of seed in the calcareous Fluvo-aquic soil (Och-Aquic Cambosols) was significant higher 4-6 times than that in the Brown soil (Hap-Udic Luvisols).(11) Copper was accumulated in the edible part of the vegetable, and the growth, development and quality of vegetable were also affected for long term application of copper-based pesticides and these effects could not be eliminated in a short time. The zinc content in the spanich was increased due to the increased content of available zinc in the BNPP treated soil. Plants were affected mostly by BDM, next was CS and the effect of BNPP was a little higher than that of KCD. Organic materials added with the 3% rate in BNPP applied soil could reduce the negative effects of BNPP on plant growth and development. Biomass of crops increased 26%-192% in the Brown soil (Hap-Udic Luvisols), and 30%-118% in the calcareous Fluvo-aquic soil (Och-Aquic Cambosols).
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