玛纳斯河流域绿洲-荒漠互馈作用的系统动力学模拟

Systematic Dynamics Analysis on Relationship between Oasis and Desert in Manasi River Basin

以玛纳斯河流域为例,在分析流域内人类活动、经济发展与生态环境耦合关系,以及绿洲与荒漠系统之间相互影响的基础上,建立系统动力学模型模拟了绿洲-荒漠系统互馈关系,重点考察了水资源变化、经济发展和生态环境环境之间的变化关系.以现状数据作为模型输入,模拟了2000—2020年社会经济发展和水资源的需求状况.结果表明,在水资源量50%保证率下,水资源可供量越来越小于经济发展的需水量,到2020年保证率将降到50%以下;总体上荒漠和山地生态环境将恶化.在调整投资比例、实行退耕还草和提高工农业的用水效率的情况下,模型模拟表明,在经济增长速度不放慢的同时,荒漠生态环境会有所改善.

The evolvement of oasis-desert system was studied though building a system dynamics model with a case study in Manasi river basin which located in the north western China, Xinjiang Uigur Autonomous Region. The model consists of mountain subsystem, oasis subsystem and desert subsystem, and the relationship between oasis and desert is investigated in this study. The impacts of human activities upon ecology, ecology to economy, and oasis to desert were analyzed with statistical data. With the current and historical data as model inputs, social product,annual water demand were predicted for the period from 2000 to 2020. The result showed that water resource would fail to meet the demand of economy, especially it would be under 50% in 2020 at water 50% probability, and the ecosystem of desert and mountain will exasperate. To achieve economy increase and environmental protection simultaneously, the current developing mode should be adjusted. With the investment ratio between the agriculture, industry, and the third industry being adjusted, water use efficiency being improved, and measures for retreat arable land to forestry or grass land being implemented, the model results showed that ecosystem of desert and mountains will obviously be ameliorated without slower the economy growth.