The immobilization of co-contaminants of organic and inorganic pollutants by biochar is an efficient remediation strategy. However, the effect of biochar amendments on the bioaccessibility of the co-contaminants in dr...The immobilization of co-contaminants of organic and inorganic pollutants by biochar is an efficient remediation strategy. However, the effect of biochar amendments on the bioaccessibility of the co-contaminants in dry versus flooded soils has rarely been compared. In batch experiments, bamboo-derived biochar（BB） had a higher sorption capacity for phenanthrene（Phe）/pyrene（Pyr）/zinc（Zn） than corn straw-derived biochar（CB）, while CB had a higher sorption capacity for lead（Pb） than BB. After 150 days of incubation, the amendments of 2% CB, 0.5% BB and 2% BB effectively suppressed the dissipation and reduced the bioaccessibility of Phe/Pyr by 15.65%/18.02%, 17.07%/18.31%and 25.43%/27.11%, respectively, in the aerobic soils. This effectiveness was more significant than that in the anaerobic soils. The accessible Zn/Pb concentrations were also significantly lower in the aerobic soils than in the anaerobic soils, regardless of treatments.The Gram-negative bacterial biomass and the Shannon–Weaver index in the aerobic soil amended with 2% CB were the highest. The soil microbial community structure was jointly affected by changes in the bioaccessibility of the co-contaminants and the soil physiochemical properties caused by biochar amendments under the two conditions. Therefore, dry land farming may be more reliable than paddy soil cultivation at reducing the bioaccessibility of Phe/Pyr/Zn/Pb and enhancing the soil microbial diversity in the short term.展开更多
The semi arid lands of Jordan are fragile and severely degraded due to low rainfall and mismanagement of natural resources.As human demands increase,sustaining the productivity of land becomes more and more important....The semi arid lands of Jordan are fragile and severely degraded due to low rainfall and mismanagement of natural resources.As human demands increase,sustaining the productivity of land becomes more and more important.Land suitability evaluation can contribute towards better land management;mitigation of land degradation;and designing land use pattern that prevents environmental problems through segregation of competing land uses.Suitability analysis allows identifying the main limiting factors for the agricultural production and enables decision makers to develop crop managements able to increase the land productivity.The purpose of this study was to develop a Geographic Information System(GIS)based approach for land use suitability assessment in order to assist land managers to identify areas with physical limitations for different land use alternatives based on research criteria developed by FAO and modified by stakeholders.This study was conducted using various data and maps incorporated within(GIS)in order to derive potential suitability for different Land Utilization Types(LUTs).Land suitability mapping was developed using an innovative approach that integrates soil and climatic data for land suitability assessment.Suitability maps for each land use were developed to show the suitability classes and display the spatial representation of soils suitable for agriculture.The output of suitability analyses provided not only the type of land use for which the land was suitable,but also information about the type of limitation(s)facing the utilization of the land.Optimum land use alternatives(scenarios)were formulated to improve and optimize the agricultural production in the study area.展开更多
基金supported by the National Key Basic Research Program of China(No.2014CB441105)the National Natural Science Foundation of China(No.41671236)+1 种基金the“135”Plan and Frontiers Program of the Institute of Soil Science,Chinese Academy of Sciences(No.ISSASIP1614)the Outstanding Youth Fund of Natural Science Foundation of Jiangsu,China(No.BK20150050)
文摘The immobilization of co-contaminants of organic and inorganic pollutants by biochar is an efficient remediation strategy. However, the effect of biochar amendments on the bioaccessibility of the co-contaminants in dry versus flooded soils has rarely been compared. In batch experiments, bamboo-derived biochar（BB） had a higher sorption capacity for phenanthrene（Phe）/pyrene（Pyr）/zinc（Zn） than corn straw-derived biochar（CB）, while CB had a higher sorption capacity for lead（Pb） than BB. After 150 days of incubation, the amendments of 2% CB, 0.5% BB and 2% BB effectively suppressed the dissipation and reduced the bioaccessibility of Phe/Pyr by 15.65%/18.02%, 17.07%/18.31%and 25.43%/27.11%, respectively, in the aerobic soils. This effectiveness was more significant than that in the anaerobic soils. The accessible Zn/Pb concentrations were also significantly lower in the aerobic soils than in the anaerobic soils, regardless of treatments.The Gram-negative bacterial biomass and the Shannon–Weaver index in the aerobic soil amended with 2% CB were the highest. The soil microbial community structure was jointly affected by changes in the bioaccessibility of the co-contaminants and the soil physiochemical properties caused by biochar amendments under the two conditions. Therefore, dry land farming may be more reliable than paddy soil cultivation at reducing the bioaccessibility of Phe/Pyr/Zn/Pb and enhancing the soil microbial diversity in the short term.
文摘The semi arid lands of Jordan are fragile and severely degraded due to low rainfall and mismanagement of natural resources.As human demands increase,sustaining the productivity of land becomes more and more important.Land suitability evaluation can contribute towards better land management;mitigation of land degradation;and designing land use pattern that prevents environmental problems through segregation of competing land uses.Suitability analysis allows identifying the main limiting factors for the agricultural production and enables decision makers to develop crop managements able to increase the land productivity.The purpose of this study was to develop a Geographic Information System(GIS)based approach for land use suitability assessment in order to assist land managers to identify areas with physical limitations for different land use alternatives based on research criteria developed by FAO and modified by stakeholders.This study was conducted using various data and maps incorporated within(GIS)in order to derive potential suitability for different Land Utilization Types(LUTs).Land suitability mapping was developed using an innovative approach that integrates soil and climatic data for land suitability assessment.Suitability maps for each land use were developed to show the suitability classes and display the spatial representation of soils suitable for agriculture.The output of suitability analyses provided not only the type of land use for which the land was suitable,but also information about the type of limitation(s)facing the utilization of the land.Optimum land use alternatives(scenarios)were formulated to improve and optimize the agricultural production in the study area.
