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This paper is intended to probe into the mechanism and environmental effects of modified chitosan, a kind of new materials, on heavy-metal contaminated soil under acid rain condition. Thereby, a leaching experiment of soil-column with simulated acid-rain trickling was conducted, leachate being collected from the soil-column, and ephehydrin modified chitosan-biochar composite (ECS-B) and protochitosan were used as stabilizers. The parameters of pH, conductivity and heavy metals (Cu, Pb, Zn and CD) of the leachate were analyzed in terms of contents and morphological change, and an accumulation-release model of heavy metals under leaching condition were put forward. The results of the experiment showed that compared with the control group, the pH value of leachae increased by 1.32 when ECS-B stabilizer had been added. EC changed significantly, rising up to 1.75 times of that of the control group; compared with the control group, the accumulative contents of Cu, Pb, Zn and Cd were decreased by 82.35%, 71.47%, 61.88% and 90.44%, respectively; and after leaching, the residual state of each heavy metal was 2.59 times higher than that of the control group. As to the study on the release of heavy metals from soil, it was considered involving a complex reaction process controlled by a variety of diffusion mechanisms. Besides, ECS-B stabilizer can inhibit the acid-rain leaching of heavy metals in soil by the increase of soil base ions, and the actions of surface complexation, precipitation and ion exchange, thus effectively reducing the ecological environment risk. [ABSTRACT FROM AUTHOR]

Copyright of Forest Engineering is the property of Forest Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aluminum toxicity in acidic soil has become one of the main factors limiting crop growth and yield. Rapeseed is an important oil crop in China, which is mainly planted in the provinces and regions of the Yangtze River Basin where soil acidification is more serious. Rapeseed is one of the crops sensitive to aluminum toxicity, but the mechanisms of aluminum tolerance are still poorly understood. This paper reviewed the production of aluminum toxicity, the effect of aluminum toxicity on crop growth, the mechanism of crop aluminum tolerance, and the research progress on aluminum tolerance of rapeseed, and provide reference for the cultivation of new varieties of aluminum tolerant and high yielding rapeseed. [ABSTRACT FROM AUTHOR]

[Objectives] This paper was aimed to study the remediation effects of phosphate-solubilizing fungi and bone char in different soils. [Methods] Three different types of lead-contaminated soils (neutral yellow brown soil, alkaline sand soil and acidic red soil)were mixed with the bone char sintered at different temperatures. We measured the contents of phosphorus and lead, and the remediation differences of different soils. The Pb bioavailability of lead-contaminated soil was then determined by planting non-heading Chinese cabbage. The application potential of compound remediation materials was confirmed by adding compound remediation agents to the soil with the best remediation effect. [Results] The bone char had the best effect of promoting the release of phosphorus in yellow brown soil, and the available phosphorus content was 64 times higher than that of the control, showing a high potential of lead remediation. The pH of yellow brown soil was neutral, and the available P in the soil would not be fixed by Ca, Fe, Al, etc., thus increasing the probability of its reaction with Pb. When bone char was solely used, the material treated at 200-300 ℃ had qualified remediation effect. We planted non-heading Chinese cabbage to verify the bioavailability of lead in yellow brown soil after bone char application. It was observed that addition of a certain proportion of bone char to yellow brown soil (the initial mass ratio of bone char to lead was over 0.5:1) could not only increase the absorption of phosphorus by 2.0 to 3.5 times, but also reduce the absorption of lead by non-heading Chinese cabbage(content of lead in pakchoi leaves was reduced by 70% to 80% compared with blank treatment). A composite of bone char and Aspergillus niger was further applied to yellow brown soil, and the effective lead was reduced to 14.36 mg·kg-1. In particular, the growth of the A. niger proved the remediation potential of the composite. [Conclusions] The composite of bone char and A. niger was suitable for lead remediation in neutral soils, and the suitable heating temperature for preparing bone char was 200-300 ℃. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mycosystema is the property of Mycosystema Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)