A located field experiment was carried out to study the effects of different amount of chemical fertilizer usage on rice yield,economic benefits of rice,soil carbon（C） and total nitrogen（TN） under ploughing back o...A located field experiment was carried out to study the effects of different amount of chemical fertilizer usage on rice yield,economic benefits of rice,soil carbon（C） and total nitrogen（TN） under ploughing back of Chinese milk vetch for 5consecutive years.Six treatments were included in the experiment,they are CK（unfertilized）,CF（100% chemical fertilizer with the amount of N,P2O5,K2 O being150,75,120 kg/hm^2respectively）,A1（22 500 kg/hm^2 Chinese milk vetch and 100%chemical fertilizer）,A2（Chinese milk vetch and 80% nitrogen and potassium fertilizer and 100% phosphate fertilizer）,A3（Chinese milk vetch and 60% nitrogen and potassium fertilizer and 100% phosphate fertilizer）,A4（Chinese milk vetch and 40% nitrogen and potassium fertilizer and 100% phosphate fertilizer）.The results were as follows：application of fertilizer could increase the yield of rice,while Chinese milk vetch combined with fertilizer application had a much more increase effect in rice yield.Under the condition of milk vetch application with 22 500 kg/hm^2,the early rice yield of the treatment A1 was significantly increased by 7.7% compared with that of CF.And the yield of treatment A3 was basically identical to or slight increase in comparison with that of CF.Decreasing amount of fertilizers cloud improve output value of rice in the case of the utilization of Chinese milk vetch.The treatment A1 increased output value of rice by 5.92% in comparison of CF,and treatment A2 was by 4.08% in the next.Treatment A4 showed much better effect in increasing soil organic carbon and total nitrogen in the paddy soil than those of treatments applying mineral fertilizer only.There was a significant reduction on soil organic carbon and TN in treatment A2 in comparison with that of CF.In general,amount of application of milk vetch with 22 500 kg/hm^2 could replace chemical fertilizer partially,it also could improve rice yield,decrease the production cost,and raise the utilization efficiency of nutrients.展开更多
There exists a logarithmic linear correlation, i. e., In C'(Z, t) = a(Z) + b(Z) ln(Z, t) where Z is the atomicnumber of element and t the year when tree ring grows between the chemical element contents in tree rin...There exists a logarithmic linear correlation, i. e., In C'(Z, t) = a(Z) + b(Z) ln(Z, t) where Z is the atomicnumber of element and t the year when tree ring grows between the chemical element contents in tree ringsC(Z, t) and those in the soils near the tree roots C'(Z, t).By determining the elemental contents of the annual growth rings of trees, we could establish the chrono-sequences of elemental contents in the tree rings, thus calculating that of the soil, that is, reproducing thedynamic changes of contents of elements in the soil C'(Z, t). The background values of elements in the soilunder site conditions of the tree could be estimated from the minimum C(Z, t_0) in the chrono-sequences ofelemental contents in the tree rings.展开更多
Soil background contents of a number of elements of different soil groups, sub-groups and genus on Liaohe River Plain were investigated. It appeared that: the background levels for most elements studied were around th...Soil background contents of a number of elements of different soil groups, sub-groups and genus on Liaohe River Plain were investigated. It appeared that: the background levels for most elements studied were around the lower limits of the world's averages, variation coefficients of the background content values were from 0.3-0.5 and the element migration coefficients were between 0.9 and 1.0. It was found that the element background contents in soils of eastern and southern parts of the area were generally higher than that of western and northern parts.展开更多
This paper deals with the soil-environmental standard. According to the current situation of researching on the soil-environmental quality guideline at home and abroad, and on the basis of the foundations and principl...This paper deals with the soil-environmental standard. According to the current situation of researching on the soil-environmental quality guideline at home and abroad, and on the basis of the foundations and principles of enacting the soil-environmental standard, the soil environment quality guideline values of Hg, Cd, Pb and As were suggested.展开更多
It was researched that the numbers and biomass of soil microorganisms in different development stage of Chinese Fir plantation in Shanxia Farm of Sub-tropical Forestry Center, CAF in Fenyi Country, Jiangxi Province. T...It was researched that the numbers and biomass of soil microorganisms in different development stage of Chinese Fir plantation in Shanxia Farm of Sub-tropical Forestry Center, CAF in Fenyi Country, Jiangxi Province. The trend of the numbers and biomass of soil microorganism, the numbers of bacteria and the content of available N, P was decreased from juvenile to medium plantation, and increased from medium to mature plantation. But it was not found the trend from the numbers of fungi and actinomycetes, the content of available K,total N, P, K, in different development stage of Chinese Fir plantation.展开更多
基金Supported by Special Fund for Agro-scientific Research in the Public Interest(201103005-08)National Science and Technology Support Program during the 12thFive-year Plan(2012BAD05B05-3)International Plant Nutrition Institute S&T Program(Hunan-16)~~
文摘A located field experiment was carried out to study the effects of different amount of chemical fertilizer usage on rice yield,economic benefits of rice,soil carbon（C） and total nitrogen（TN） under ploughing back of Chinese milk vetch for 5consecutive years.Six treatments were included in the experiment,they are CK（unfertilized）,CF（100% chemical fertilizer with the amount of N,P2O5,K2 O being150,75,120 kg/hm^2respectively）,A1（22 500 kg/hm^2 Chinese milk vetch and 100%chemical fertilizer）,A2（Chinese milk vetch and 80% nitrogen and potassium fertilizer and 100% phosphate fertilizer）,A3（Chinese milk vetch and 60% nitrogen and potassium fertilizer and 100% phosphate fertilizer）,A4（Chinese milk vetch and 40% nitrogen and potassium fertilizer and 100% phosphate fertilizer）.The results were as follows：application of fertilizer could increase the yield of rice,while Chinese milk vetch combined with fertilizer application had a much more increase effect in rice yield.Under the condition of milk vetch application with 22 500 kg/hm^2,the early rice yield of the treatment A1 was significantly increased by 7.7% compared with that of CF.And the yield of treatment A3 was basically identical to or slight increase in comparison with that of CF.Decreasing amount of fertilizers cloud improve output value of rice in the case of the utilization of Chinese milk vetch.The treatment A1 increased output value of rice by 5.92% in comparison of CF,and treatment A2 was by 4.08% in the next.Treatment A4 showed much better effect in increasing soil organic carbon and total nitrogen in the paddy soil than those of treatments applying mineral fertilizer only.There was a significant reduction on soil organic carbon and TN in treatment A2 in comparison with that of CF.In general,amount of application of milk vetch with 22 500 kg/hm^2 could replace chemical fertilizer partially,it also could improve rice yield,decrease the production cost,and raise the utilization efficiency of nutrients.
文摘There exists a logarithmic linear correlation, i. e., In C'(Z, t) = a(Z) + b(Z) ln(Z, t) where Z is the atomicnumber of element and t the year when tree ring grows between the chemical element contents in tree ringsC(Z, t) and those in the soils near the tree roots C'(Z, t).By determining the elemental contents of the annual growth rings of trees, we could establish the chrono-sequences of elemental contents in the tree rings, thus calculating that of the soil, that is, reproducing thedynamic changes of contents of elements in the soil C'(Z, t). The background values of elements in the soilunder site conditions of the tree could be estimated from the minimum C(Z, t_0) in the chrono-sequences ofelemental contents in the tree rings.
文摘Soil background contents of a number of elements of different soil groups, sub-groups and genus on Liaohe River Plain were investigated. It appeared that: the background levels for most elements studied were around the lower limits of the world's averages, variation coefficients of the background content values were from 0.3-0.5 and the element migration coefficients were between 0.9 and 1.0. It was found that the element background contents in soils of eastern and southern parts of the area were generally higher than that of western and northern parts.
文摘This paper deals with the soil-environmental standard. According to the current situation of researching on the soil-environmental quality guideline at home and abroad, and on the basis of the foundations and principles of enacting the soil-environmental standard, the soil environment quality guideline values of Hg, Cd, Pb and As were suggested.
文摘It was researched that the numbers and biomass of soil microorganisms in different development stage of Chinese Fir plantation in Shanxia Farm of Sub-tropical Forestry Center, CAF in Fenyi Country, Jiangxi Province. The trend of the numbers and biomass of soil microorganism, the numbers of bacteria and the content of available N, P was decreased from juvenile to medium plantation, and increased from medium to mature plantation. But it was not found the trend from the numbers of fungi and actinomycetes, the content of available K,total N, P, K, in different development stage of Chinese Fir plantation.
