Study on Intensive Land Use of Urban Built-up Area of Mega-cities in China
The approach of factor analysis was adopted to integrated assess of intensive land use in urban built-up area from China's 16 megacities,meanwhile,the study put these urban built-up area into order based on the level of development. The results showed that intensive land use efficiency of urban built-up area of megalopolis exist three characteristics,it is the lower overall level and the significant geographic differences and the different emphasis of the influence factors in each mega-cities. Therefore,the industrial structure in mega-cities should be adjusted reasonably to promote the sustainable development for the city's economy; the cities land consolidation should be carried out to improve the efficiency of land use; the cities ecological environmental protection should be enlarged to improve the ecological benefits of land use.
With the zhuzhi 8 as material ,researched the effects on agronomy character under different cultivated density. Experiment results showed that:Density affects sesame production construction and bear character,then affects sesame production directly. 5000 ～10000 is the best cultivated density range.