The strongest documented seismic disaster ever occurred in the Po Plain area (January 3, 1117, M = 6.5) involved significant damage over a large zone. The genetic mechanism of such </span><span style="fo...The strongest documented seismic disaster ever occurred in the Po Plain area (January 3, 1117, M = 6.5) involved significant damage over a large zone. The genetic mechanism of such </span><span style="font-family:Verdana;">an </span><span style="font-family:Verdana;">event, most probably caused by more than one earthquake, is still </span><span style="font-family:Verdana;">an </span><span style="font-family:Verdana;">object of debate. Above all, the sources so far proposed cannot account for significant features of the observed macroseismic field. In this work, we suggest that the damage in the Verona zone was caused by the activation of a fault in the Lessini tectonic district, while damage in the central Po Plain may be related to a thrust fault located beneath the Giudicarie belt. The effects felt in northern Tuscany might derive from the seismic activ</span><span style="font-family:Verdana;">ation</span><span style="font-family:""><span style="font-family:Verdana;"> of the pre</span><span style="font-family:Verdana;">sumed SW-ward buried prolongation of the Giudicarie fault. The presence of such transpressional lithospheric discontinuity in the Adriatic domain since the upper Miocene and its reactivation (Pliocene-Pleistocene</span><span style="font-family:Verdana;">) as a thrust zone is mainly suggested by an accurate analysis of the observed deformation pattern in the central Mediterranean region. The proposed Giudicarie source may also help to explain the damage observed in the central Po Plain on December 25, 1222, which is not compatible with the seismic sources so far proposed.展开更多
The connection of farmland consolidation construction works was studied,to provide theoretical and practical basis for bringing into play optimal functions.It employed theoretical analysis method,case analysis method,...The connection of farmland consolidation construction works was studied,to provide theoretical and practical basis for bringing into play optimal functions.It employed theoretical analysis method,case analysis method,and experience summary method.Through empirical study of Si County in Anhui Province,it further analyzed connection of four works:land consolidation,irrigation and drainage,field roads,farmland protection,and ecological and environmental protection,to provide methods and possibilities for coordination and connection of four works.It is required to take the land consolidation as a system,take full consideration of all aspects,attach great importance to connection of four works,so as to bring into full play optimal functions and realize sustainable use of land resources and sustainable development of social economy.展开更多
In recent years,Cadmium(Cd)pollution has been found in many soil geochemical surveys in Northern Zhejiang Plain,a crucial rice production area in East China,located in the lower Yangtze River.To more scientifically pr...In recent years,Cadmium(Cd)pollution has been found in many soil geochemical surveys in Northern Zhejiang Plain,a crucial rice production area in East China,located in the lower Yangtze River.To more scientifically predict the effect of soil Cd on rice safety,data including 348 local rhizosphere soil-rice samples obtained in 2014 were used in this study.Meanwhile,we extracted 90% of random samples as variables based on soil Cd content(Cd_(soil)),soil organic matter(SOM),pH,and other indicators.In addition,a multivariate linear model for rice Cd content(Cd_(rice))prediction based on the indicators including the soil Cd content(Cd_(soil)),the soil organic matter(SOM),and the pH value.The remaining 10%of random samples were used for the significance test.Based on the 2014 soil Cd content(Cd_(soil14))and the 2019 soil Cd content(Cd_(soil19)),this study predicted Cd content in 2019 rice grains(Cd_(p-rice19)).The spatio-temporal variation of Cdrice was contrasted in the five years from 2014 to 2019,and the risk areas of rice safety production were analyzed using the Geographical Information System(GIS).The results indicated that compared with the actual Cd content in 2014 rice grains(Cdrice14),the proportion of Cd_(p-rice19),which exceeded the standard food level in China(GB2762-2017),increased dramatically.Moreover,the high-value areas of Cdrice distributed greatly coincidentally in these two years.By contrast,both Cdrice and Cdsoil show very different spatial scales.The dominant reason is the distribution of the local canal systems,indicating that economic activities and agricultural irrigation may aggravate the risk of soil Cd pollution,thus threatening safe rice production.展开更多
文摘The strongest documented seismic disaster ever occurred in the Po Plain area (January 3, 1117, M = 6.5) involved significant damage over a large zone. The genetic mechanism of such </span><span style="font-family:Verdana;">an </span><span style="font-family:Verdana;">event, most probably caused by more than one earthquake, is still </span><span style="font-family:Verdana;">an </span><span style="font-family:Verdana;">object of debate. Above all, the sources so far proposed cannot account for significant features of the observed macroseismic field. In this work, we suggest that the damage in the Verona zone was caused by the activation of a fault in the Lessini tectonic district, while damage in the central Po Plain may be related to a thrust fault located beneath the Giudicarie belt. The effects felt in northern Tuscany might derive from the seismic activ</span><span style="font-family:Verdana;">ation</span><span style="font-family:""><span style="font-family:Verdana;"> of the pre</span><span style="font-family:Verdana;">sumed SW-ward buried prolongation of the Giudicarie fault. The presence of such transpressional lithospheric discontinuity in the Adriatic domain since the upper Miocene and its reactivation (Pliocene-Pleistocene</span><span style="font-family:Verdana;">) as a thrust zone is mainly suggested by an accurate analysis of the observed deformation pattern in the central Mediterranean region. The proposed Giudicarie source may also help to explain the damage observed in the central Po Plain on December 25, 1222, which is not compatible with the seismic sources so far proposed.
基金Supported by Soft Science Project of Anhui Provincial Department of Land and Natural Resources(2015801)
文摘The connection of farmland consolidation construction works was studied,to provide theoretical and practical basis for bringing into play optimal functions.It employed theoretical analysis method,case analysis method,and experience summary method.Through empirical study of Si County in Anhui Province,it further analyzed connection of four works:land consolidation,irrigation and drainage,field roads,farmland protection,and ecological and environmental protection,to provide methods and possibilities for coordination and connection of four works.It is required to take the land consolidation as a system,take full consideration of all aspects,attach great importance to connection of four works,so as to bring into full play optimal functions and realize sustainable use of land resources and sustainable development of social economy.
基金Geological Prospecting Funds Program of Zhejiang Province,China,No.2018003,No.2020006Science and Technology Program of Department of Natural Resources of Zhejiang Province,China,No.2020-45Key R&D Program of Zhejiang Province,China,No.2021C04020。
文摘In recent years,Cadmium(Cd)pollution has been found in many soil geochemical surveys in Northern Zhejiang Plain,a crucial rice production area in East China,located in the lower Yangtze River.To more scientifically predict the effect of soil Cd on rice safety,data including 348 local rhizosphere soil-rice samples obtained in 2014 were used in this study.Meanwhile,we extracted 90% of random samples as variables based on soil Cd content(Cd_(soil)),soil organic matter(SOM),pH,and other indicators.In addition,a multivariate linear model for rice Cd content(Cd_(rice))prediction based on the indicators including the soil Cd content(Cd_(soil)),the soil organic matter(SOM),and the pH value.The remaining 10%of random samples were used for the significance test.Based on the 2014 soil Cd content(Cd_(soil14))and the 2019 soil Cd content(Cd_(soil19)),this study predicted Cd content in 2019 rice grains(Cd_(p-rice19)).The spatio-temporal variation of Cdrice was contrasted in the five years from 2014 to 2019,and the risk areas of rice safety production were analyzed using the Geographical Information System(GIS).The results indicated that compared with the actual Cd content in 2014 rice grains(Cdrice14),the proportion of Cd_(p-rice19),which exceeded the standard food level in China(GB2762-2017),increased dramatically.Moreover,the high-value areas of Cdrice distributed greatly coincidentally in these two years.By contrast,both Cdrice and Cdsoil show very different spatial scales.The dominant reason is the distribution of the local canal systems,indicating that economic activities and agricultural irrigation may aggravate the risk of soil Cd pollution,thus threatening safe rice production.
