Zhang Yang-zhu

Effect of different fertilization treatments on yield and nutrients uptake of Chinese cabbage and cabbage

A field plot experiment was conducted to study effect of different fertilization treatments on yield,nutrients uptake and nutrients use efficiency of Chinese cabbage and cabbage.The results showed that:yield of cabbage and Chinese cabbage of the application of manure,oil cake and special fertilizer for vegetables combined with fertilizer is higher than that of the pure chemical fertilizer treatment.The yield of application of special fertilizer for vegetables combined with fertilizer of Chinese cabbage is the highest,yield of it enhanced 25.30% compared with the pure chemical fertilizer treatment;application of oil cake and special fertilizer for vegetables combined with fertilizer are of the highest N and P nutrient use efficiency,N and P nutrient use efficiency of them enhanced 21.65%,10.77% compared with the pure chemical fertilizer treatment,respectively.The yield of application of oil cake combined with fertilizer of cabbage is higher,yield of it enhanced 9.90% compared with the pure chemical fertilizer treatment;application of oil cake combined with fertilizer is of the highest N and P nutrient use efficiency,N and P nutrient use efficiency of it enhanced 29.23% and 14.9% compared with the pure chemical fertilizer treatment,respectively.

Effect of biochar from peanut shell on speciation and availability of lead and zinc in an acidic paddy soil

Biochar has been used to reduce the mobility and availability of heavy metals in contaminated paddy soils. A pot experiment was carried out to analyze the effects of peanut shell biochar (PBC) on the speciation and phytoavailability of Pb and Zn in contaminated acidic paddy soil using rice (Oryza sativa L.) as an indicator plant. Peanut shell biochar was applied to an acidic paddy soil contaminated with Pb and Zn at four rates (0%, 1%, 2%, and 5% w/w), and rice plants were grown in this soil. The soil pH, cation exchange capacity (CEC), water-soluble SO42-, dissolved organic carbon (DOC), CaCl2-extractable heavy metals, and speciation of heavy metals were determined. Additionally, biomass and concentrations of heavy metals in rice tissues were determined. The application of PBC significantly increased the pH, CEC, water-soluble SO42-, and DOC in the paddy soil, but decreased the content of CaCl2-extractable Pb and Zn. The CaCl2-extractable Pb and Zn showed significant negative correlations with the pH, CEC, water-soluble SO42-, and DOC (p < 0.05). Following the application of biochar to the contaminated paddy soil, the Pb and Zn concentrations in the CaCl2 extracts were reduced by 41.04-98.66% and 17.78-96.87% (p < 0.05), respectively. Sequential chemical extractions showed a reduction in the acid-soluble Pb and Zn fraction and an increase in the reducible fraction following the addition of biochars. PBC obviously inhibited the uptake and accumulation of Pb and Zn in the rice plants. The Pb concentrations in the rice grain were significantly reduced by 60.32%, with the addition of 5% PBC. Neither of the biochars significantly changed the Zn concentrations in the rice grain. The influence of biochar on Pb and Zn phytoavailability varied not only with the application rate of biochar, but also with the kind of metals. Overall, the use of peanut shell biochar at a high application rate is more effective in immobilizing Pb and Zn in the acidic paddy soil contaminated with heavy metals, especially in reducing the phytoavailability of Pb to the rice plants.

Inorganic nitrogen fractions and profile distribution characteristic in vegetable soil derived from river alluvial in Dongting Lake plain

By means of both field investigation samples and indoor analysis,The inorganic nitrogen fractions and profile distribution characteristic in vegetable soil derived from river alluvial in dongting lake plain were researched.The result indicated that the content of total nitrogen varies from 0.65~1.67 g/kg,the average value and coefficient of variation is respectively 1.25 g/kg and 15.54%.The average value of fixed ammonium is 290 mg/kg,accounting for 23.2% of total nitrogen.The content of NO3--N and NH4+-N is respectively 46.00 mg/kg and 1.91 mg/kg.The content of total N,NH4+-N,and fixed ammonium decreased with the increasing of soil profile depth in 0~80 cm.NO3--N display leaching phenomenon from surface soil to subsoil.

Restorational effect of various fertilizations on red soil derived from various parent material.

Effect of 3 fertilization systems in restoring the eroded red soil caused by soil erosion,which is a severely eroded red soil derived from Quaternary Red Clay,granite and slate,were studied with a pot experiment. The results showed that applying soil ameliorant Ⅱcould increase content of available P and organic material compared with applying chemical fertilizer,and also it could alleviate soil acidification and promote the use efficiency of soybean for fertilizer N and K,increase biomass and the number of microbe in soil . Applying organic fertilizer can increase the content of available N,P and K and organic material,while it also promote the use efficiency of soybean for fertilizer N,P and K,and increase microbial activities compared with application of chemical fertilizer. Of the three kinds of red soil derived from parental material, the available nutrient of Quaternary Red Clay was higher than granite and slate,and the utilization efficiency of soybean for fertilizer N grown on slate was higher than granite, but the utilization efficiency of soybean for fertilizer K grown on granite was lower than Quaternary Red Clay and slate, more fertilizer K should be applied to granite and slate.