排序方式: 共有3条查询结果,搜索用时 0 毫秒
1
1.
Assessing potential production of maize using simulation models for land evaluation in Brazil 总被引:2,自引:0,他引:2
Abstract. The paper highlights the advantages of modelling to simulate dynamic processes and to couple environmental data more closely with effects on crops. The CERES-Maize crop model and the DSSAT software package were selected for the work and the region of the Triângulo Mineiro in the state of Minas Gerais was selected as the study area. The results showed that there are differences in the potential production of the Latosols of the Triângulo Mineiro and this should be taken into account when extrapolating or transferring technology for other regions within the same cerrado ecosystem of central-west Brazil. It is essential to improve the number of points with weather data collection since, as demonstrated for Frutal, the climate of the Triângulo can determine differences in potential agricultural production as well as risk for production. The study showed that the use of crop models can improve land suitability evaluations, for land use planning, or establishing strategies for rural funding. 相似文献
2.
Eleonora Deschamps Virginia S. T. Ciminelli Frank Thomas Lange J?rg Matschullat Brigitte Raue Hanka Schmidt 《Journal of Soils and Sediments》2004,4(3):169
Soils and sediments around gold ore deposit and mining sites in the Iron Quadrangle present positive As anomalies (median
concentrations > 100 mg kg-1) and wide ranges (< 20 to > 2000 mg kg-1) even in densely populated areas. These anomalies can be related to geological structures, to hydrothermal ore deposits and
to their continuous exploitation over the past three centuries. The paper presents new data on both As geochemistry and soil
and sediment geochemistry in general, and discusses consequences of the encountered anomalies, their reasons and potential
effects and how they compare with current screening and threshold values. While surface soil As-val-ues are reproducible at
a given site, sediment anomalies show a strong seasonal variation that can be explained by tropical hydrologicai variances.
Suggestions are presented on how to minimize the As-load in densely populated areas that might otherwise pose a potential
health risk. 相似文献
3.
Eleonora?DeschampsEmail author Virginia?S.?T.?Ciminelli Frank?Thomas?Lange J?rg?Matschullat Brigitte?Raue Hanka?Schmidt 《Journal of Soils and Sediments》2002,2(4):216-222
Soils and sediments around gold ore deposit and mining sites in the Iron Quadrangle present positive As anomalies (median
concentrations > 100 mg kg-1) and wide ranges (< 20 to > 2000 mg kg-1) even in densely populated areas. These anomalies can be related to geological structures, to hydrothermal ore deposits and
to their continuous exploitation over the past three centuries. The paper presents new data on both As geochemistry and soil
and sediment geochemistry in general, and discusses consequences of the encountered anomalies, their reasons and potential
effects and how they compare with current screening and threshold values. While surface soil As-values are reproducible at
a given site, sediment anomalies show a strong seasonal variation that can be explained by tropical hydrological variances.
Suggestions are presented on how to minimize the As-load in densely populated areas that might otherwise pose a potential
health risk. 相似文献
1