【作者】 郗静；

【导师】 曹明明；

【作者基本信息】 西北大学 ， 人文地理学， 2009， 博士

【摘要】 土地利用/覆被变化(Land Use and Land Cover Change,LUCC)是当前全球环境变化研究的前沿领域,开展典型区域的案例研究是认识全球变化的重要途径。利用土地利用情景模拟模型揭示自然环境与人类活动之间的动态反馈关系,探索LUCC驱动机制是学术界长期关注的热点问题之一。区域土地利用/覆被时空格局变化是错综复杂的多种驱动力共同作用的结果,然而所有驱动力最终通过土地经营者的行为产生作用。对典型区域土地经营者的土地利用行为选择的影响因素、决策过程以及决策导致的土地利用变化进行深入解析,明确土地经营者的土地利用行为选择机制,是揭示LUCC微观行为机制的一个有效途径。退耕还林政策是我国迄今为止涉及农户参与面最广的一项公共政策,该政策实践迫切需要农户土地利用行为选择机制作为其理论支撑。本研究选择陕西省米脂县为典型区域,从人地系统互动的角度出发,通过多学科、多视角、多层次的分析,综合集成GIS技术和模型方法,对退耕还林政策影响下区域LUCC宏观过程、格局以及微观行为机制进行了深入剖析,得出如下几点结论:(1)中尺度宏观过程、格局研究中,选取米脂县为研究区域,利用RS和GIS技术获取了1990年、1999年、2006年米脂县土地利用变化特征,采用土地利用类型动态度、土地利用类型相对变化率、土地利用转移矩阵以及景观格局指数分析等方法,分析了退耕还林政策实施前(1990—1999年)与实施后(1999—2006年)米脂县土地利用时间过程和空间格局变化。将定性分析与定量计算相结合,对研究时段内该县土地利用变化的政策驱动效应进行了分析。结论认为,退耕还林政策加快了米脂县耕地的流转速度,对区域土地利用变化产生了显著影响。(2)选取米脂县高渠乡和杨家沟镇为样本区,通过农户问卷调查,掌握样本区退耕还林政策实施的现状,明晰农户对退耕还林政策的认知和判断情况,了解农户参与退耕还林政策的意愿与行为选择结果,理解农户现在及将来可能面对的影响与压力。结论认为:农户对退耕还林政策的态度(包括对政策的认知、判断和意愿)与其具体的行为选择存在群体的一致性和个体的差异性;通过Logit模型计算,识别出耕地收入、副业收入、打工收入、户主年龄、是否种植经济作物、行政村是否有后续产业是退耕还林政策影响农户土地利用决策的主导因素,各因素的影响程度和影响方向具有差异性。以上研究为下一步划分农户智能体的类型、确定农户智能体的行为规则、农户对退耕还林政策的土地利用行为响应分析等方面的研究奠定了充分的实证基础。(3)小尺度微观行为研究中,选取米脂县高渠乡刘渠村、冯渠村、高西沟村和陈家沟村为典型区域,将宏观过程与格局分析和微观行为机制研究相结合,建立了区域土地利用/覆被变化的智能体模型(Agent-based models of Land use and land cover change,ABMs/LUCC),并对模型中的行为人,即农户智能体的行为选择及其对研究区LUCC的影响进行了重点分析。以农户家庭户主的土地利用选择偏好作为分类依据,采用分类树方法对农户智能体类型进行划分;基于有限理性决策理论,引用经历—权重吸引模型(EWA),对农户智能体的目前生产策略决策过程和退耕还林政策期满后农户对不同生产策略的选择概率进行了分析;最后,在ERDAS环境下对退耕还林政策期满后农户的复垦行为进行了情景分析,认为政府制定并实施的相关政策措施对于纠正农户的有限理性行为偏差,维持和巩固退耕还林政策成果具有重要作用。(4)综合分析了退耕还林政策影响下农户土地利用行为选择的自然、经济、社会驱动机制以及农户对自然因素、经济因素和社会因素的土地利用行为响应。结论认为:农户的土地利用行为选择必须遵循自然规律、生态适应性规律,遵守国家宏观政策的约束,同时还必须根据自身的需求和市场状况及时调整土地利用行为。农户始终是在目前土地利用类型与未来土地利用类型的效益比较中确定新的土地利用行为选择。社会因素是农户土地利用选择中最难以估量的影响因素。总体上看,农户土地利用行为选择以自然条件为制约,受经济利益驱使,而社会变迁为其行为改变提供了可能。因此,农户层面区域土地利用/覆被变化是自然、经济、社会因素共同作用的结果。综上所述,本研究一方面从中尺度区域分析的角度揭示了土地利用/覆被变化的一般规律、趋势和宏观机制,另一方面从小尺度典型区域分析的角度进一步揭示了区域LUCC时空格局演变的细节过程与微观行为机制,避免了单一尺度分析的表面性,因此能够更好地阐明土地利用/覆被变化的轨迹与过程,为科学合理地制定区域可持续发展政策,提高政策的可操作性和实施效果提供借鉴。更多还原

【Abstract】 Land use and land cover change (LUCC) is the key frontier issues of global environment change research, and typically regional case sdudy is an important way to understand global change effect. It is one of the hot issues that researchers explore LUCC driving mechanism through land use scenario simulation models to show dynamic feedback relationship between physical environment and human activities. There are numerous and complicated driving forces acting on regional land use and land cover spatio-temporal pattern, but all driving forces take effect by land use decision-makers. So, a useful way to explor LUCC micro behaviour mechanism is to study on factors influencing landholder’s choices, process forming decision, and land use change outcomes. So far, Grain for Green policy is the only one public policy involved wide range of households. Therefore, in order to put the policy into practice successfully, it urgently needs theoretical principle of households land use behaviour choice mechanism. Based on multidisciplinary, multiple points of view, and multilevel analysis combined with GIS and models, the paper study on regional LUCC macro process and pattern, micro behaviour mechanism which affected by Grain for Green plicy. Some conclusions were put forward as follows:(1) Study on macro process and pattern in mesoscale, taking Mizhi County as research area, land use characteristic of Mizhi County, respectively in 1990, 1999, and 2006, were acquired by RS and GIS approach. Contrastive analysis of outcomes of LUCC in Mizhi County in temporal process and spatial pattern before and after GFGP which is the two periods during 1990 to 1999 and 1999 to 2006, were given by using the mathematical method to calculate the dynamic degrees of certain and synthesis land types, the land type conversion matrix changes and landscape analysis, et al. Then, using qualitative method, LUCC policy driving mechanism was put forward. GFGP accelerated farmland conversion speed in Mizhi County, and influenced the land use change significantly.(2) Based on questionnaire survey of Gaoqu Township and Yangjiagou Township in Mizhi County, current status of GFGP, households’ attitude and behaviour choice were studied. Results show that, in samples, there were not only similarities in the entirety but also differences in the individual between households’ attitude, including cognition, judgment, inclination, and intention. Through Logit model analysis, main factors of households’ land use decision-making after GFGP were studied. Results show that, five main factors of households’ land use decision-making were proposed and the incidence of each factor was diversified. All results done above make a solid empirical research foundation for the next study of dividing household types, spatial distribution, behaviour rules and households’ land use choices responding to GFGP, et al.(3) Study on micro behaviour mechanism in small scale, taking Luiqu Village, Fengqu Village, Gaoxigou Village, and Chenjiagou Village in Gaoqu Township as typical case research area, combining process and pattern analysis with behaviour mechanism, conceptual model of agent-based models of land use and land cover change (ABMs/LUCC) was set up, and household anget behaviours and their effects on LUCC were analyzed specifically. Taking household’s land use preference as classification rule, household agent types were divided though classification tree. Different choosing process of current production strategies and theirs probabilities after expiration of GFGP chosen by various types of household agents’ were put forward by experience-weighted attraction model (EWA) based on bounded -rational approach. Finally, forecasting the results of households’ recultivation behaviour after the expiration of GFGP by scenario analysis method. The results show that relative policies are useful to rectify deviation of households’ bounded-rational behaviours and reinforce outcomes of GFGP.(4) Using comprehensive analysis method, physical, economic, and social driving mechanism of household land use choice and their behaviour response were given. Conclusions show that, household land use choice must abide by the order of nature, ecological adaptability, and restriction of national macro policies. At the same time, household also need to adjust their land use behaviour according to demands and market situation, because household decide to change land use choice based on the comparative profits between present land use types and future land use types. Social factors were the most difficult estimated aspect of household land use choices. In all, household land use behaviour confined by physical condition, driven by economic benefits, and behaviour modification permited by social change. So, regional land use change in household level is involved in factors of nature, economy and society. In the context, the paper reveals LUCC general discipline, tendency and macro mechanism by regional analysis in mesoscale, and further explains details and micro mechanism of LUCC spatio-temporal pattern by typical area research in order to avoid superficiality caused by single scale analysis. In a word, conclusions aim to give some useful suggestions to draw up sustainable development policy and improve maneuver ability of relative policies.更多还原