基于区域产量法测算的福建省农业生态足迹

为了使生态足迹模型能更好地反映区域实际,文章对生态足迹模型中的计算项目做了较大改进。首次计算了肉类的耕地生态足迹和人畜排泄物污染生态足迹。新建了纳污土地、CO2吸收林地、水资源地三种生态足迹类型以强调农业污染的严重性和土地、林地的多重生态功能;将化石能源地并入CO2吸收林地;剔除牧草地类型,将肉类耗粮生态足迹并入耕地类型;将污染源从化石燃料扩展到人畜排泄物、化肥、农药领域,计算了CO2、N、P和农药等污染物的生态足迹。用福建省最近5 a的平均产量测算了2007年福建农业生态足迹,包括农业投入品生态足迹、农业劳动力消费生态足迹和农业污染物排放生态足迹三部分,然后与生态承载力分类比较以测度农业生产的生态占用情况。测算结果表明,2007年福建省农业生态足迹中,林地、水域、建成地、纳污土地占有实际生态承载力的比例较低,分别为1.4%、1.2%、13.4%和24.6%;而耕地占生态承载力的比例达到了94.2%;水资源地是实际生态承载力的2.2倍,出现了严重的生态赤字。最后提出相应的建议。

Agricultural Ecological Footprint in Fujian Province Base on Regional Yield Method

In order to make Ecological Footprint (EF) model better reflecting regional realities, the article significantly improved the calculating items of EF model. The arable land EF of meat and pollution EF of excreta of poultry, livestock and human were accounted firstly. Three EF categories, namely CO₂ absorption forest, decomposition land and water collection area were established to show the seriousness of agricultural pollution and the multiple ecological functions of arable land and forest. Fossil-fuel land was contained by forest land for absorbing CO₂; grazing land was canceled while the EF of grain used to produce meat was added arable land. The concerning pollution sources were expanded from fossil fuels to chemical-fertilizer, pesticide and excreta of poultry, livestock and human. Furthermore, the EF of pollutants such as CO₂, N, P and pesticide was counted.Fujian’s agricultural EF in 2007 was calculated by using average yields per-unit in recent five years, including the EF of direct inputs, farmers’ consumption and pollutants in agricultural practice. The category comparison between agricultural EF and Fujian’s Ecological Capacity (EC) was used to reflect the agricultural ecological-occupancy in the province. The calculation results indicated that the agricultural EF of forest-land, wetland, built-up area and pollutants-absorption land occupied small proportion of Fujian’s EC in 2007, being respectively 1.4%, 1.2%, 13.4% and 24.6%. This was largely due to high ecological productivity in the province and low consumption in underdevelopment rural areas. However, 94.2% of arable land EC was occupied by agriculture because of less arable land areas per capita and overdevelopment in grain-consumption livestock, which consumed 73.8% of the arable land EC. The EF of water collection area was 2.2 times that of relevant EC, indicating that serious ecological deficit occurred. In water collection area category, chemical fertilizer, excretion and freshwater aquaculture contributed respectively 36.8%, 23.5%, 39.7% in N and 41.8%, 12.9%, 45.4% in P. Some corresponding suggestions were proposed.