基于参与式调查与主成分分析的金塔绿洲变化驱动力分析

内陆河流域绿洲变化驱动机制是旱区绿洲学研究的核心内容之一。利用1963~2010年的Keyhole存档相片、KATE-200卫星航片、Landsat遥感影像等多源数据,获取了金塔绿洲空间分布及面积变化信息。在此基础上,结合参与式调查和主成分分析方法定量分析绿洲变化的驱动机制。研究表明：近47 a来金塔绿洲总体呈现增长的趋势,绿洲规模不断扩大,至2010年绿洲面积高达539.47 km²。其主要原因是气候变化、人口增加、水资源的开发利用与科技进步、社会经济发展及政策等因子的相互交织作用。气候变化是背景因子,人文因子是绿洲变化的主成分因素,且在不同历史社会背景下,其主导人文因素也不同。

Driving Forces of Jinta Oasis Changes Based on Participatory Rural Appraisal and Principal Component Analysis

As a unique geographical landscape of arid area, oasis was the main space of human activity in arid area, and its change was the most direct reflection of environmental change. Recently, spatiotemporal change of oasis and its driving forces was one of the hot issues of oasis study. Jinta oasis, a typical artificial and agricultural oasis in the lower reaches of Beida River Basin in arid China, had experienced drastic change in the past 50 years, was selected as a case to study the spatiotemporal change and its driving forces. Based on Keyhole satellite photograph, KATE-200, Landsat MSS, TM and ETM images in 1963-2010, as well as field interviews and governmental socioeconomic statistics data, this study investigated and discussed the driving forces of Jinta oasis change during 1963-2010 by combining with participatory rural appraisal and principal component analysis. The results showed that oasis area and scale expanded gradually, and the area achieved its maximum with 539.47 km² in 2010. Oasis changes had been resulted from the interaction of natural environmental changes and human activities. Human driving factors include population, policy, economic development, the progress of agricultural science and technology, environmental awareness, while the natural environment change was been represented by climatic factors (such as rainfall, air temperature) and runoff. In our study, the first and second main components of driving forces were population growth, water resources development and utilization, technical renovation, economic development and policy, the thirds was annual temperature, suggesting that human driving force played a dominant role. In addition, the main human driving forces behind oasis changes were varied in different historical periods. In 1963-1980, the dominant driving force was population growth and policy, whereas the dominant driving forces in 1980-1990 were the changes in agricultural production ways (such as household contract responsibility system) and population growth. In the period of 1990-2000, all sorts of driving forces interacted and associated mutually. Since 2002, economic benefit and water utilization were the dominant factors.