北京市水-能源-粮食可持续发展系统动力学模型构建与仿真

Establishment and Simulation Study of System Dynamic Model on Sustainable Development of Water-Energy-Food Nexus in Beijing

资源与环境是人类生存和发展的重要基础。北京是中国的政治文化中心,资源高度依赖外省市供应,随着需求的不断增加,其可持续发展将面临更加严峻的挑战。本研究通过构建以水-能源-粮食(W-E-F)三者为主体并涵盖社会、经济和环境子系统的复杂系统因果关联网络;运用系统动力学仿真技术,实现了对北京市水-能源-粮食关联(W-E-F Nexus)系统的动力学仿真模拟,预测了北京市W-E-F变化趋势,并开展了W-E-F Nexus系统敏感性分析。研究发现2020年水资源消耗总量预计超过38亿吨;能源供应数量预计不足2600万吨标准煤,地热能等清洁一次能源供应逐渐占据主导地位,能源消费总量预计下降至6865万吨标准煤,其中超过62%的能源消耗将依赖省外调入;粮食消费总量预计将超过730万吨,粮食单产数量在2014-2016年经过短暂调整后开始持续提升,到2020年每公顷产量预计将超过7800公斤,粮食自给率经过调整将再度恢复到2012年20%的水平;能源系统是现阶段提升北京W-E-F综合可持续发展能力的突破口;相比于单一资源政策,基于非资源系统的决策行为影响效果将更为深广。

Resources and environment are important basis for human survival and development. Beijing,as the political and cultural center,is seriously short of natural resources,and depends exceptionally heavily on imports from other provinces. Therefore,the city is facing tougher challenges with resource needs rising steadily. This paper sets up a complex system of interconnections among water,energy and food. A W-E-F Nexus causal network is established after collecting influence factors. This paper realizes the simulation of regional W-E-F development trends,and carries out a sensitivity analysis based on system dynamics model. According to the simulation results,total consumption of water is expected to rise to 3. 84 billion tons in Beijing by 2020. Energy supplies will tail off to below 26 million tons standard coal equivalent（ SCE）,primary energy is seeking continuous,incremental improvements,where the proportion of cleaner fuels is boosting,such as geothermal energy. Total consumption of energy will reduce gradually to 68. 65 million tons SCE by 2020,of which more than 62 percent will be imported from other provinces. Total consumption of food is expected to rise to 7. 3 million tons and after the short adjustment periods from 2014 to 2016,yield per unit area will increase continuously to more than 7. 8 thousand kilograms by 2020 and degree of self-sufficiency will return to 20 percent. Meanwhile,policies and measures based on energy system will improve sustainable development ability fundamentally,and prove to be critical factors promoting regional development in Beijing. There will be larger and deeper influences when control measures are taken through social and economic means,saying non-resource factors,compared with direct resource regulations.