Based on a large number of relevant literatures, the effects of environmental factors and human factors on forest soil nutrients in nature reserve were summarized, as well as the soil quality assessment and correlatio...Based on a large number of relevant literatures, the effects of environmental factors and human factors on forest soil nutrients in nature reserve were summarized, as well as the soil quality assessment and correlation of soil. nutrients, to provide references for a deep research on forest nature reserve soil and its protection. The distribution of forest soil nutrients has significant spatial heterogeneity, and its final distribution pattern is the result of joint action of environmental factors, including topography, vegetation, soil type, seasonal change as well as soil microorganism, and human factors. In natural ecosystem, environmental factors are the main factors that determine the differences of soil nutrients. Effective human management can promote the accumulation of forest soil nutrients, but improper interference will cause a significant loss of soil nutrients. Accurate soil quality evaluation can objectively clarify the impact of different soil management practices on soil, contributing to the timely adjustment of management measures. The establishment of long-term soil monitoring stations in forest nature reserves is a good way to master the influencing factors and the mechanism of forest soil nutrients, and can ultimately provide theoretical guidance for a sustainable and healthy operation of forest nature reserve.展开更多
The ability to manage and restore plant communities in the face of human-induced landscape change may rely on our ability to predict how species respond to environmental variables.Understanding this response requires ...The ability to manage and restore plant communities in the face of human-induced landscape change may rely on our ability to predict how species respond to environmental variables.Understanding this response requires examining factors or their interactions that have influence on plant and resource availability.Our objective was to analyze the relationships between changes in plant abundance and the interaction among environmental habitat factors including soil, geological(rock type), and other environmental variables in the Longhushan karst mountains ecosystem.Species density and dominance were examined using ANOVA, ANCOVA,and Generalized Linear Models to establish the single or combined effects of these groups of factors.The results showed that trends in abundance were mainly affected by rock type(related to the percentage content of dolomite and calcite), soil characteristics in association with topography.Both plant indices were higher in dolomite dominated areas and varied positively with moisture, and elevation, but negatively with organic matter, while density also increased with slope degree.The results demonstrate that significant variations in species abundance was produced with the combination of variables from soil, geological, andenvironmental factors, suggesting their interaction influence on plants.We postulate that spatial variations in plant abundance in karst ecosystem depends on the carbonate rock type in addition to water and nutrient availability which are mainly controlled by topography and other factors such as soil texture and temperature.The study suggests that in karst areas carbonate rock type, in addition to local environmental variables, should be taken into account when analyzing the factors that have impact on plant communities.展开更多
Soil salinity has been considered a brutal environmental factor for decreasing crop yield due to the accumulation of excessive sodium salts in soil under arid and semi-arid region of the world. This study tries to add...Soil salinity has been considered a brutal environmental factor for decreasing crop yield due to the accumulation of excessive sodium salts in soil under arid and semi-arid region of the world. This study tries to address the potential use of biochar. An organic matter rich material, used to reclaim salt-stressed soil in order to enhance crop production in dry croplands as well as to increase soil organic carbon （SOC） and to improve soil fertility. In this regard, a field experiment for two years was conducted in a moderately salt-stressed soil of Central China with wheat-maize cropping system. The soil was amended with biochar composted with poultry manure （BPC） at 12 t/ha with diluted pyroligneous solution （PS） at 0.15 t/ha a week before sowing of crop. Results showed significant improvement in soil physical properties, soil nutrient content with reduction of sodium salts and soil pH by amendment of BPC-PS1 and BPC-PS2 over the experimental control salt-stressed cropland. Furthermore, wheat and maize grain yield, nitrogen, phosphorous potassium and K/Na ratio increased while sodium decreased with the application of BPC-PS amendment in wheat and maize grain. This study concluded that the biochar amendment in conjunction with PS greatly improved SOC storage, crop nutrient uptake and soil fertility. Thus, waste treatment of crop straw and poultry manure compost as biochar could be combined to alleviate salt stress and improve crop production in the vast area of arid and semi-arid regions of the world.展开更多
Disposal of chromium （Cr） hexavalent form, Cr（Ⅵ）, in soils as additions in organic fertilizers, liming materials or plant nutrient sources can be dangerous since Cr（Ⅵ） can be highly toxic to plants, animals, a...Disposal of chromium （Cr） hexavalent form, Cr（Ⅵ）, in soils as additions in organic fertilizers, liming materials or plant nutrient sources can be dangerous since Cr（Ⅵ） can be highly toxic to plants, animals, and humans. In order to explore soil conditions that lead to Cr（Ⅵ） generation, this study were performed using a Paleudult （Dystic Nitosol） from a region that has a high concentration of tannery operations in the Rio Crande do Sul State, southern Brazil. Three laboratory incubation experiments were carried out to examine the influences of soil moisture content and concentration of cobalt and organic matter additions on soil Cr（Ⅵ） formation and release and manganese （Mn） oxide reduction with a salt of chromium chloride （CrCl3） and tannery sludge as inorganic and organic sources of Cr（Ⅲ）, respectively. The amount of Cr（Ⅲ） oxidation depended on the concentration of easily reducible Mn oxides and the oxidation was more intense at the soil water contents in which Mn（Ⅲ/Ⅳ） oxides were more stable. Soluble organic compounds in soil decreased Cr（Ⅵ） formation due to Cr（Ⅲ） complexation. This mechanism also resulted in the decrease in the oxidation of Cr（Ⅲ） due to the tannery sludge additions. Chromium（Ⅲ） oxidation to Cr（Ⅵ） at the solid/solution interface involved the following mechanisms： the formation of a precursor complex on manganese （Mn） oxide surfaces, followed by electron transfer from Cr（Ⅲ） to Mn（Ⅲ or Ⅳ）, the formation of a successor complex with Mn（Ⅱ） and Cr（Ⅵ）, and the breakdown of the successor complex and release of Mn（Ⅱ） and Cr（Ⅵ） into the soil solution.展开更多
基金Supported by the Special Fund for Biodiversity Protection of the Ministry of Environmental Protection of the People’s Republic of China(214704)the Special Fund for the Fundamentak Works of the Ministry of Science and Technology(2008FY110304)~~
文摘Based on a large number of relevant literatures, the effects of environmental factors and human factors on forest soil nutrients in nature reserve were summarized, as well as the soil quality assessment and correlation of soil. nutrients, to provide references for a deep research on forest nature reserve soil and its protection. The distribution of forest soil nutrients has significant spatial heterogeneity, and its final distribution pattern is the result of joint action of environmental factors, including topography, vegetation, soil type, seasonal change as well as soil microorganism, and human factors. In natural ecosystem, environmental factors are the main factors that determine the differences of soil nutrients. Effective human management can promote the accumulation of forest soil nutrients, but improper interference will cause a significant loss of soil nutrients. Accurate soil quality evaluation can objectively clarify the impact of different soil management practices on soil, contributing to the timely adjustment of management measures. The establishment of long-term soil monitoring stations in forest nature reserves is a good way to master the influencing factors and the mechanism of forest soil nutrients, and can ultimately provide theoretical guidance for a sustainable and healthy operation of forest nature reserve.
基金founded by the National Natural Scientific Foundation of China(Grant No.40972218)the Fundamental Research Founds for National University,China University of Geosciences(Wuhan)(Grant Nos.G1323521125,G1323521225,G1323521325)
文摘The ability to manage and restore plant communities in the face of human-induced landscape change may rely on our ability to predict how species respond to environmental variables.Understanding this response requires examining factors or their interactions that have influence on plant and resource availability.Our objective was to analyze the relationships between changes in plant abundance and the interaction among environmental habitat factors including soil, geological(rock type), and other environmental variables in the Longhushan karst mountains ecosystem.Species density and dominance were examined using ANOVA, ANCOVA,and Generalized Linear Models to establish the single or combined effects of these groups of factors.The results showed that trends in abundance were mainly affected by rock type(related to the percentage content of dolomite and calcite), soil characteristics in association with topography.Both plant indices were higher in dolomite dominated areas and varied positively with moisture, and elevation, but negatively with organic matter, while density also increased with slope degree.The results demonstrate that significant variations in species abundance was produced with the combination of variables from soil, geological, andenvironmental factors, suggesting their interaction influence on plants.We postulate that spatial variations in plant abundance in karst ecosystem depends on the carbonate rock type in addition to water and nutrient availability which are mainly controlled by topography and other factors such as soil texture and temperature.The study suggests that in karst areas carbonate rock type, in addition to local environmental variables, should be taken into account when analyzing the factors that have impact on plant communities.
文摘Soil salinity has been considered a brutal environmental factor for decreasing crop yield due to the accumulation of excessive sodium salts in soil under arid and semi-arid region of the world. This study tries to address the potential use of biochar. An organic matter rich material, used to reclaim salt-stressed soil in order to enhance crop production in dry croplands as well as to increase soil organic carbon （SOC） and to improve soil fertility. In this regard, a field experiment for two years was conducted in a moderately salt-stressed soil of Central China with wheat-maize cropping system. The soil was amended with biochar composted with poultry manure （BPC） at 12 t/ha with diluted pyroligneous solution （PS） at 0.15 t/ha a week before sowing of crop. Results showed significant improvement in soil physical properties, soil nutrient content with reduction of sodium salts and soil pH by amendment of BPC-PS1 and BPC-PS2 over the experimental control salt-stressed cropland. Furthermore, wheat and maize grain yield, nitrogen, phosphorous potassium and K/Na ratio increased while sodium decreased with the application of BPC-PS amendment in wheat and maize grain. This study concluded that the biochar amendment in conjunction with PS greatly improved SOC storage, crop nutrient uptake and soil fertility. Thus, waste treatment of crop straw and poultry manure compost as biochar could be combined to alleviate salt stress and improve crop production in the vast area of arid and semi-arid regions of the world.
基金Supported by the Soil Testing Laboratory Project,Federal University of Rio Grande do Sul,Brazil.
文摘Disposal of chromium （Cr） hexavalent form, Cr（Ⅵ）, in soils as additions in organic fertilizers, liming materials or plant nutrient sources can be dangerous since Cr（Ⅵ） can be highly toxic to plants, animals, and humans. In order to explore soil conditions that lead to Cr（Ⅵ） generation, this study were performed using a Paleudult （Dystic Nitosol） from a region that has a high concentration of tannery operations in the Rio Crande do Sul State, southern Brazil. Three laboratory incubation experiments were carried out to examine the influences of soil moisture content and concentration of cobalt and organic matter additions on soil Cr（Ⅵ） formation and release and manganese （Mn） oxide reduction with a salt of chromium chloride （CrCl3） and tannery sludge as inorganic and organic sources of Cr（Ⅲ）, respectively. The amount of Cr（Ⅲ） oxidation depended on the concentration of easily reducible Mn oxides and the oxidation was more intense at the soil water contents in which Mn（Ⅲ/Ⅳ） oxides were more stable. Soluble organic compounds in soil decreased Cr（Ⅵ） formation due to Cr（Ⅲ） complexation. This mechanism also resulted in the decrease in the oxidation of Cr（Ⅲ） due to the tannery sludge additions. Chromium（Ⅲ） oxidation to Cr（Ⅵ） at the solid/solution interface involved the following mechanisms： the formation of a precursor complex on manganese （Mn） oxide surfaces, followed by electron transfer from Cr（Ⅲ） to Mn（Ⅲ or Ⅳ）, the formation of a successor complex with Mn（Ⅱ） and Cr（Ⅵ）, and the breakdown of the successor complex and release of Mn（Ⅱ） and Cr（Ⅵ） into the soil solution.
