The validity of the concept of coastal equilibritun depends upon a pnd of the ekistence of equilibrium. In addition, the methods of calculating the actual equilibrium profile and the response time are rempred. This st...The validity of the concept of coastal equilibritun depends upon a pnd of the ekistence of equilibrium. In addition, the methods of calculating the actual equilibrium profile and the response time are rempred. This study evaluates equilibriuzn conditions using evidence from EOF (empirical orthogonal function) analysis of the coased profile data (bed slopes and associated elevations) obtained from Poole and Christchurch Bays, southem England. The preliminary results show tha the larges eigenvalue is much greater than the other eigenvalues and the temporally-related eigenfunction is staionary;thes observation implies the existence of wilibrium. Further, the spatially-related eigenfunction associated with the largest eigenvalue is used to calculate the actual beach profile at equilibrium. Although the temporal eigenfopction may nuctuate, it recovers rapidly, indicating tha the response time is short. However, further studies are required to determine the response hme accurately.展开更多
Ivory Coast is a country rich in base metals and precious minerals: gold, manganese, diamond, iron, bauxite, cobalt and nickel. These natural resources are exposed to destruction and fragmentation by mining activities...Ivory Coast is a country rich in base metals and precious minerals: gold, manganese, diamond, iron, bauxite, cobalt and nickel. These natural resources are exposed to destruction and fragmentation by mining activities. The artisanal and small-scale exploitation of gold are increasingly practiced in our rural areas. These activities escape often in the control and monitoring of the mining administration. In order to better constrain these activities on the environment, the present work used remote sensing imageries to see its spatio-temporal impacts in the rural world in central Ivory Coast. The results show that gold artisanal activities have been practiced since 2013 and are experiencing an increasingly important growth. We note a devastation of forests and savannahs, a pollution of surface water, as well as an increase in poverty in rural areas. These activities are practiced near habited areas (villages). This creates a reduction of cultivatable soil. Remote sensing imageries make it possible to quickly map areas at large-scale gold mining in time and space.展开更多
文摘The validity of the concept of coastal equilibritun depends upon a pnd of the ekistence of equilibrium. In addition, the methods of calculating the actual equilibrium profile and the response time are rempred. This study evaluates equilibriuzn conditions using evidence from EOF (empirical orthogonal function) analysis of the coased profile data (bed slopes and associated elevations) obtained from Poole and Christchurch Bays, southem England. The preliminary results show tha the larges eigenvalue is much greater than the other eigenvalues and the temporally-related eigenfunction is staionary;thes observation implies the existence of wilibrium. Further, the spatially-related eigenfunction associated with the largest eigenvalue is used to calculate the actual beach profile at equilibrium. Although the temporal eigenfopction may nuctuate, it recovers rapidly, indicating tha the response time is short. However, further studies are required to determine the response hme accurately.
文摘Ivory Coast is a country rich in base metals and precious minerals: gold, manganese, diamond, iron, bauxite, cobalt and nickel. These natural resources are exposed to destruction and fragmentation by mining activities. The artisanal and small-scale exploitation of gold are increasingly practiced in our rural areas. These activities escape often in the control and monitoring of the mining administration. In order to better constrain these activities on the environment, the present work used remote sensing imageries to see its spatio-temporal impacts in the rural world in central Ivory Coast. The results show that gold artisanal activities have been practiced since 2013 and are experiencing an increasingly important growth. We note a devastation of forests and savannahs, a pollution of surface water, as well as an increase in poverty in rural areas. These activities are practiced near habited areas (villages). This creates a reduction of cultivatable soil. Remote sensing imageries make it possible to quickly map areas at large-scale gold mining in time and space.