( 2 ) the time series of ecological footprint from 1980 to 1999 are calculated using ecological footprint model ; and the ecological capacity of three years are calculated according the ecological land classification from remote sensed data , and then the ecological deficit of three years are acquired by the difference between ecological capacity and ecological footprint . beijing mountainous region became ecological unsustainable development in 1999 and the ecological deficit was 0 . 27ha per capita . the counties including fangshan , changping and pinggu had the serious ecological deficits ( 2 )运用生态足迹模型计算了北京山区1980 - 1999年生态足迹时间序列，并采用遥感技术手段完成三个时间断点的生态土地分类，计算相应的生态容量，进行了三个时间段的生态盈亏分析，进入21世纪，北京山区处于生态不可持续状态， 1999年人均生态赤字0 . 27ha ，其中房山、昌平、平谷生态赤字较为严重。
Each of the optimization model is put forward to achieve the economic and social profits . the first schema is the grain security model , by which 193 million kilogram of commodity will be supplied and the per capita grain yield is 717 kilogram in 2010 . in this model 12 . 86 million kilogram net fertilizer is needed and the cost will reach 122 million yuan 粮食安全型方案；以粮食产量为目标，到2010年人均粮食产量717公斤，为国家贡献商品粮1 . 93亿公斤； 2002年至2010年，粮食总产量年增长率为0 . 8 ；农民人均种植业纯收益1277元。这种方案需要肥料纯量1286万公斤，物质费用1 . 22亿元。
