Study on Changes of Ecosystem Service Value of Overlapped Area of Coal and Crop—— A Case Study of Zoucheng City
Based on Costanza's evaluated result about the value of the world's ecosystem services,this paper analyzed the changes of land use and ecosystem services value from 1996 to 2003 in Zoucheng City.Through the study,the authors found that the cultivated land,fruit land and woodland were decreased,but the building land and water area were increased.Because the water area had a high unit ecosystem services value,the value of ecosystem services was increasing from 1996 to 2003 in Zoucheng City.Ecosystem services value was increasing from 95.9704 million US dollars in 1996 to 104.5830 million US dollars in 2003.The increasing rate of ecosystem services value was 8.97%.
Aiming at Shenyang Metro in construction,analysis of influence of advance small duct grouting on metro tunnel excavation is conducted.By different layout in ring of small duct,based on surrounding rock stress and displacement of each monitored point of tunnel,the rational layout is given.which has important reference meaning to similar tunnel engineering.