【作者】 吴冠岑；

【导师】 刘友兆；

【作者基本信息】 南京农业大学 ， 土地资源管理， 2008， 博士

【摘要】 土地是财富之母,又是人类的立身之本;人类赖土地以生存繁衍,人类社会又因依存土地而发展。曾几何时,人类利用土地创造了光辉灿烂的古代文明,但同时人类活动的加剧和人类对土地资源的不合理开发利用也使得这些辉煌的文明遭到毁灭性地破坏。时至今日,土地生态系统仍然持续面临着来自人类日益严重的破坏,这甚至也威胁到人类自身的安全。世界各国实践表明,不符合生态规律的人类经济活动如对土地资源的过度开发、陡坡垦荒、大面积森林砍伐、草场过牧、工业污染、城市过度集中拥挤等等,都会引起严重的土地生态危机并造成土地生态系统的退化。人类从违背土地生态系统发展规律而屡受自然界惩罚,饱受灾难折磨的深刻教训中,逐渐醒悟到:根治这一危及人类自身安全问题的唯一途径是维持土地生态系统安全发展。土地生态安全预警可以起到防范于未然的作用,是维护土地生态安全并控制土地生态系统恶化的有效办法。它在把握土地生态安全演变规律基础上,辨识土地生态安全警情及其严重程度,以便在土地生态系统发生退化质变之前,及早提出预告、报警,并及时采取措施,加以有效抑制、减缓、控制、整治,以使土地生态系统步入良性循环。开展区域土地生态安全预警研究无疑对完善土地生态安全理论、维护土地生态安全并实现区域可持续发展都具有重要的理论意义和应用前景。基于此,论文借鉴已有土地生态安全研究和预警研究,将预警理论引入土地生态安全研究领域,形成较为系统的区域土地生态安全预警研究体系。首先,论文对土地生态安全、预警和区域土地生态安全预警的概念进行界定,并对土地生态安全演化的原理进行分析,以便为接下来的研究提供铺垫;其次,论文对区域土地生态安全预警研究的分析原则、特征和功能进行了阐述,并提出,总体分析框架;接着,依据区域土地生态安全预警分析框架对区域土地生态安全预警指标体系的构建、警情分析模型和排警调控体系开展深入的探讨;最后以江苏淮安市为例对土地生态安全预警研究进行详细的实证分析。论文认为土地生态安全本质上是围绕区域人类社会经济可持续发展目标,促使土地资源与人类的协调发展以及土地自然、社会、经济复合生态系统的可持续发展。它包括两层基本涵义,一层涵义是土地生态系统自身的安全;第二层涵义是土地生态系统对人类的安全。区域土地生态安全预警指分析土地生态安全演变规律,明晰影响区域土地生态安全关键的因素和功能,制定反映研究区域土地生态安全特点的区域土地生态安全预警指标体系及预警指标警限,利用数学模型对土地生态安全现状和未来进行测度、分析与评价,预报不正常的时空范围和危害程度,对于已有问题提出解决措施,对于即将出现的问题给出防范和调控措施的建议,并以此指导土地生态安全保障体系建立。土地生态安全演变可以认为是土地生态系统的安全水平在动态演化中不断形成耗散结构,而且这种安全状态的耗散结构本身处在不断发展变化的过程;土地生态安全发展演变过程中还存在能够在某一短时间内发生的、可以造成土地生态系统巨大破坏甚至崩溃的突变现象;土地生态安全子系统之间,子系统各要素之间,以及系统与环境之间普遍存在着相互联系、相互制约、相互促进、协同发展的规律。在分析土地生态安全的演化原理后,论文指出区域土地生态安全的分析原则包括一般性与特殊性相结合、实用性、前馈性、定性与定量分析相结合和规范与实证分析相结合等5项原则;同时,区域土地生态安全预警应该具有复杂性、多功能性、动态性和有限性等特征,并包括预见、监测评估、防范、调控和指导等功能,其总体分析框架主要包括预警指标体系构建、警情分析和排警调控3大模块。在总体分析框架内,论文指出:区域土地生态安全预警指标体系主要由土地生态安全的自然因素、经济因素和社会因素等3个子系统组成,预警指标警限确定方法可以大致归纳为相对确定法和绝对确定法2类。警情分析模型包括警情预测模型和警情评价模型2方面构成,一方面是以BP神经网络为基础的警情预测模型;另一方面是以“变权”综合评价为基础的警情评价模型。区域土地生态安全预警级别可以划分为无警区间、轻警区间、中警区间、重警区间、巨警区间等5个区间。土地生态安全排警调控的基本结构由调控主体和受控对象、输入与输出、目标与行为、信息及其传输和反馈、决策与措施等5部分构成,兼具有导向、协调、自控、稳定等4项功能。土地生态安全排警调控过程包括了解受控对象、确定调控目标、反馈调控信息、制定调控方案、实施调控方案、调整控制状态等6个阶段。土地生态安全排警调控机制包括规划、法律、行政、政策、决策、协调、经济等7个方面。在以上理论分析之后,论文以淮安市为例进行了土地生态安全预警实证研究。结果发现:淮安市土地生态安全状态总体处于中警区间,存在不稳定趋势。2001-2005年为淮安市土地生态安全发展较好阶段,研究年内淮安市土地生态安全状况总体有所提升,但波动较大,特别是经济因素子系统发展变动较大且朝不利方向变化。如果保持目前发展趋势不作出积极有效的调控,2006-2010年间淮安市土地生态安全状况会比2005年有一定程度退化并保持处于中警区间。同时,淮安市土地生态安全状态变化对自然因素子系统和社会因素子系统比较敏感。淮安市土地生态安全预警指标体系中包括土地潜在生产力实现水平等15项关键因子,其中:土地生态安全的经济因素子系统和社会因素子系统关键因素对相应子系统的贡献比自然因素子系统关键因素对相应子系统贡献大。如果相关部门提高重视,按照研究针对15项关键因素提出的10项排警调控措施方面齐抓共管,并达到研究设定的2010年淮安市土地生态安全关键影响因素的排警调控目标,淮安市土地生态安全状况将逐渐转入轻警区间。更多还原

【Abstract】 Land is mother of wealth, land is foundation of human. Human depends on the land to survival and multiply, human society develops because of the land dependence. Not long ago, human has created the magnificent ancient civilization using the land, but simultaneously the human activity aggravating and the unreasonable land development and utilization increasing makes these brilliant civilization suffering ruinous destruction. Until today, the land ecosystem still continues to face from the growing serious destruction of human, even that also threatens human own security. Various countries practice indicated that all kinds of human economic activities incompatible with ecological law, such as over-exploitation of land resources, reclamation on steep slopes, large deforestation, over-herding on pasture, industrial pollution, excessive concentration of urban congestion and so on, will lead to arousing serious ecological crisis and even to causing land ecosystem degradation. From the frequent natural punishment and the profound lessons of tortured disaster caused by violating land ecosystem law, the humanity gradually awaken to: the only way for radical curing this problem endangering human own security is to maintain safe development of land ecosystem. Early warning of land ecological security can play a "nip in the bud" role in the maintenance of land ecological security and control of land ecosystem deterioration, which is an effective way. Based on grasping evolution law of land ecological security, early warning study of regional land ecological security can identification warning condition and its severity of land ecological security, so that people can as early as possible make warning and alarming and take measures to effectively inhibit, mitigate, control, regulation before the land ecosystem degradation and qualitative change, which can make land ecosystem step into benign cycle. Development of early warning study of regional land ecological security is undoubtedly of great theoretic meaning and application prospect to perfect land ecological security theory, maintain land ecological security and realize regional sustainable development.Based on above, using for reference of existing land ecological security research and warning research, this paper introduces warning theory to land ecological security research field, and forms more systematic research system about early warning of regional land ecological security. Firstly, this paper defines the concepts of land ecological security, early warning, early warning of regional land ecological security, and analyses evolution principle of land ecological security so as to further carrying out research on early warning of regional land ecological security. Secondly, this paper expounds analysis principle, characteristics, and function about study on early warning of regional land ecological security, and puts forward general analysis framework. According to the general analysis framework, this paper further discusses the construction of early warning index system of regional land ecological security, analysis model of warning condition and regulation system for eliminating warning of regional land ecological security. Finally, this paper takes Huaian City as an example and makes a detailed demonstration analysis.This paper holds that the essence of land ecological security is harmonious development between land resource and human and sustainable development of Natural-Social -Economic complex land ecosystem aiming at regional sustainable development. It consists of double meaning: one is the land ecosystem self-security, another is land ecosystem security to human. Research on early warning of regional land ecological security is meant analysis of evolution principle of land ecological security, clarity of critical factors and functions affecting land ecological security, establishment of early warning index system of regional land ecological security reflecting characteristic of regional land ecological security and warning threshold of these indexes, measure, analysis and evaluation of present and future situation of land ecological security using mathematical model, forecast of abnormal space-time range and damage degree, present of solving measures about existing problem and preventing suggestions about upcoming problem that is used in guiding the construction of guarantee system for land ecological security.It is consider that evolution of land ecological security is that dissipative structure is formed by land ecological security level in the process of dynamic development which is constant change and development, that catastrophic phenomenon exists in evolution process of land ecological security which can occur at a short time and cause destruction and collapse of land ecosystem, that there exists commonly mutual correlation, mutual restriction, mutual promotion, and coordinated development rule among land ecological security subsystems, among every element in subsystem, and between land ecological security system and environment.After above analysis of evolution principle of land ecological security, this paper points out: For early warning of regional land ecological security, the analysis principles should consist of combination with generality and specialty, practicality, feedforward, combination with qualitative analysis and quantitative analysis, combination with normative analysis and empirical analysis. Not only some typical characters such as complication, multi-function, dynamic and limitation etc. can be clearly showed, but also some functions of forecast, inspection, regulation and guide are included in early warning of regional land ecological security. Moveover, the general analysis framework is to be constructed mostly by three parts: index system of early warning, analysis model of warning condition and regulation system for eliminating warning.Within this general analysis framework, this paper points out: Early warning index system of regional land ecological security should consist of those three subsystem, such as nature subsystem, society subsystem, and economic subsystem. The methods about determination of warning threshold mainly should be concluded two kinds of absolute determination and relative determination. Analysis model of warning condition consists of two sub-model: one is prediction sub-model of warning condition based on BP neural network, another is evaluation sub-model of warning condition based on variable weight comprehensive evaluation. Warning condition level should be divided into five grades: no warning condition, light warning condition, moderate warning condition, severe warning condition, tremendous warning condition. To regulation system for eliminating warning of land ecological security: The basic structure should consist of five part: regulation subject and controlled object, input and output, goal and behavior, information transmission and its feedback, decision and measure. The function of regulation system for eliminating warning of land ecological security should consist of guide, coordination, self-control, and steady. The process should consist of six stages: investigate controlled object, determine regulation goal, feed back regulation information, make regulation project, implement regulation project, adjust controlled condition. The mechanism should consist of seven respects: planning mechanism, legal mechanism, administration mechanism, policy mechanism, decision mechanism, coordination mechanism, economic mechanism.After that theoretical analysis, this paper carries out a demonstration by taking Huaian City as an example. The results show that: the general status of land ecological security is in situation of moderate warning condition in Huaian City and there is unstable trend in development process of land ecological security in Huaian City. The general status of land ecological security is fairly well during the period from 2001 to 2005 in Huaian City, and the general status of land ecological security improves with great fluctuation. Especially, the status of economic subsystem decreases toward unfavorable direction with great fluctuation. If this trend at present is kept and no positive and effective measures are made, the general status of land ecological security has a little falling and is still in situation of moderate warning condition in Huaian City. Moreover, the general status of land ecological security is sensitive to nature subsystem and society subsystem. In addition, there are fifteen key factors in early warning index system for land ecological security in Huaian City, and the contribution of these key factors among economic subsystem and society subsystem to their responsive subsystem is bigger than the contribution of these key factors among nature subsystem. If concerned departments increasingly pay attention to this question, and take comprehensive management measures according to the ten aspects for these fifteen key factors proposed in this study, and complete the setting regulation target of these key factors for eliminating warning of land ecological security in 2010, the general status of land ecological security will gradually step into light warning condition.更多还原