基于GIS-LCA的陕西黄连木生物柴油能量生产及环境潜力研究

To provide the basis for the uncertainties of developing biodiesel from Pistacia chinensis in Shannxi province, land resources suitable for Pistacia chinensis planting and their spatial distribution, suitability degrees were investigated, then total net energy production potential and GHG emission reduction potential derived from large-scale planting of Pistacia chinensis were estimated, based on GIS and Life Cycle Analysis. Multi-factor comprehensive analysis method was used to identify land resources suitable for Pistacia chinensis cultivation, make suitability assessment, and obtain their spatial distribution, suitability degree and total amount. Then, using LCA method, the life cycle net energy and greenhouse gas emission reduction capacity of marginal land resources with different suitability degrees for biodiesel production was calculated. The life cycle model was expanded to obtain the potentiality of total net energy production and greenhouse gas emission reduction of Pistacia chinensis plantation. Finally, based on ecology model simulation and field investigation, the changes of study vegetation NPP and carbon in soil after the change of land use patterns were analyzed and compared with the above model output, in order to evaluate greenhouse gas emission reduction potential of biodiesel from Pistacia chinensis. The results can provide scientific data and the theoretical basis for China's regional bio-energy industry decision

针对生物燃料在能量生产和温室气体减排作用中的不确定性，本研究以陕西黄连木生物柴油生产为例，利用耦合地理信息系统（GIS）空间分析与生命周期分析（LCA）进行能源植物开发利用潜力评估的技术方法，通过识别黄连木生长的生态限制因子，基于最新土地利用、气象、土壤、DEM等数据，运用多因子综合评价方法，建立1km空间栅格数据的黄连木种植适宜性综合评价模型，获取适宜于黄连木规模化种植的土地资源与空间分布；利用修改后LCA模型，定量估算不同适宜性土地发展黄连木生物柴油的净能量/净排放值并分析总产能/减排潜力。同时基于生态学模型模拟及地面调查，确定土地利用方式改变前后地上植被NPP和土壤碳储量的变化，并将结果对比分析，客观评价黄连木生物柴油的温室气体减排潜力。为我国区域生物能源产业决策提供科学数据和理论依据。

本研究为准确评估陕西省发展黄连木生物柴油的潜力，利用100米像元的土地利用数据、DEM数据、土壤数据、气象数据，获得了陕西省适宜发展黄连木种植的土地资源的空间分布和类型数据。结果表明，陕西省共有可用于黄连木种植的土地资源5706385公顷，其中等级为适宜的土地资源1230265公顷，等级为较适宜的土地资源4476120公顷。中等覆盖度草地为最主要类型，占总面积的43.78%；高覆盖度草地、灌丛和疏林地所占比重分别为21.6%、17.36%和13.28%。而等级为适宜的土地，主要分布在汉中、安康和商洛，分别为450816、297001和308690公顷。研究结果与实地调查数据吻合较好。对比分析表明，数据像元大小、土壤有机质含量对于最终结果具有较大影响。考虑副产品能量分配后，利用适宜土地在副产品分配后净能量达到18.486MJ/L，能量比达到2.223；而较适宜土地的净能量和能量比分别达到14.871MJ/L和1.794。有效利用生产过程中的副产品，能够大幅提高生物柴油生命周期能源效率。本结果可用于陕西省和各地区黄连木发展的具体实施。