漓江上游土地利用与覆盖变化及其驱动力研究

漓江上游是漓江流域主要的水源林区域,也是漓江风景名胜区重要的生态安全屏障。借助Arc GIS和ENVI软件,对2002年和2013年两期遥感影像数据进行解译,结合土地利用和覆盖研究方法,分析了漓江流域上游土地利用类型结构的变化以及土地变化的人文驱动因子。研究表明:2002~2013年漓江上游土地利用结构稳定,生态环境保持良好。在整体结构中,土地利用类型主要以林地和耕地为主。土地利用和覆盖变化呈现林地、耕地减少,草地、湿地和人工表面增加的趋势。在短时间尺度上,人类的社会经济活动是漓江流域土地利用/覆盖变化最主要的驱动因素。     

疏勒河中下游绿洲土地利用变化及其驱动力分析

通过1990、2000、2005和2010年4期遥感影像解译结果,获取了近20年来疏勒河流域中下游绿洲的土地利用变化数据,进一步利用土地利用动态变化模型,对疏勒河流域中下游绿洲土地利用变化过程、趋势及其驱动机制进行了深入分析。结果表明:近20年来疏勒河流域中下游绿洲土地利用类型仍以草地、水域和耕地为主,土地利用整体特征未发生显著改变,但不同土地利用类型的变化差异较大;其中,研究期内耕地呈持续高速增长态势,草地出现较大的波状起伏,水域面积于2000年后持续减少;1990—2005年草地和水域面积减少引起绿洲缓慢萎缩,2005—2010年草地和耕地面积增大导致绿洲缓慢扩张;人口、政策方向、城市化程度和技术水平等人文因子是绿洲变化的主要驱动力。     

土地利用／土地覆盖变化与土地利用规划——以安徽马鞍山市为例

利用马鞍山市1983、1996、2010年的土地详查、土地现状和土地规划数据,分析了马鞍山市1983—1996年以及1997-2010规划年土地利用类型结构的变化及其土地变化的驱动因子。通过相关分析揭示出：马鞍山市1983年以来土地利用／土地覆盖变化主要表现为耕地减少和建设用地的增加,耕地减少的主要驱动因子是人口增加、工业和农业的发展;规划期土地利用／土地覆盖变化的驱动因子是土地管理、人口和社会经济的发展;新的土地管理法的严格施行,将使今后我国区域土地利用／土地覆盖变化不同程度的向着有利于经济、社会和生态环境的方向发展。     

土地利用时空变化及其驱动因子分析——以宁波市鄞州区为例

进入21世纪,土地利用/土地覆盖变化(LUCC)成为重点研究领域。文章通过Arcgis软件支持对鄞州共7年的土地利用的土地利用动态度,地类之间的转换方向以及土地利用时空变化等三方面进行分析,并对主要地类变化的驱动力因子进行了量化分析。研究结果表明:(1)鄞州区土地利用呈现高速、复杂的变化;(2)耕地呈现出高度的单向不平衡转移,转移方向呈多方向性;(3)建设用地空间变化最大,呈现出了不可逆的高度扩张性;(4)总人口的增长,工业的发展,国内生产总值和财政收入的增加是鄞州建设用地扩张的主要驱动因子;人口的增长,特别是非农业人口的增长日益成为鄞州耕地变化的主要驱动因素。     

基于土地转移流的干旱区河谷城市土地系统稳定性评价——以兰州市近郊四区为例

以位于西北的河谷型城市兰州市市区为例,引入流分析和土地利用活跃度分析,基于Landsat遥感影像数据,采用土地利用变化测度模型和主成分分析方法对研究区土地利用时空动态特征及其驱动机制进行了分析。研究表明:①研究区未利用土地资源较少,后备土地资源严重不足,林地、草地、水域比例较低,存在较大生态风险;②建设用地与耕地、草地、林地之间的转移关系是土地利用转移的关键关系,决定着研究区土地利用变化特征;③土地利用变化具有阶段性,随着社会经济高速发展,城镇化的快速推进导致土地系统熵值增加,稳定性降低。     

建三江垦区土地利用/覆盖变化与生态环境效应作用机理研究

以黑龙江省建三江垦区为研究区,以1989年和2006年两期TM遥感影像为主要信息源,利用遥感与地理信息系统相结合的方法,提取研究区土地利用/覆盖信息,运用数学模型计算土地利用/覆盖变化度并分析其总体特征,探讨选取用地类型变化的生态贡献率参数和生态环境指数,反映和揭示研究区土地利用/覆盖变化与生态环境响应。结果表明:土地利用/覆盖变化与生态环境相互作用和相互影响。1989-2006年,研究区土地利用/覆盖发生了很大的变化,水田和草地覆盖类型变化最为频繁、速度也最快,建设用地变化最慢。期间生态环境有恶化也有改善。在各种用地类型的变化中,沼泽湿地减少的生态贡献率最大,造成了生态环境的负面效应。研究表明,人们不合理的开发利用土地,会造成生态环境的恶化,从而使原有土地利用/覆盖方式被迫发生相应改变。     

山东半岛北部海岸带土地利用变化与驱动力——以龙口市为例

海岸带土地利用/覆盖变化是“海岸带陆-海相互作用计划“的重要研究领域,利用1992.6、2002.6两期Landsat TM影像,采用监督分类和人机交互解译相结合的方法完成土地利用/覆盖类型的计算机解译,采用叠加分析方法,研究了山东半岛北部海岸带地区龙口市10年间土地利用的变化特征.结果表明:研究时段内园地、水浇地、水体、林地面积都有不同程度的减少;城乡用地、旱地、草地面积增加,其中城乡用地增幅最大,年变化率为5.34%;土地利用转换类型复杂多样,转换比例相对较大.相关性分析和主成分分析表明,该区土地利用变化主要受经济因素影响.     

巢湖流域土地利用/覆盖变化态势及生态系统服务价值时空变化研究

以巢湖流域为研究案例区,利用1991～2001年的土地利用详查和变更调查数据为主要数据源,分析了巢湖流域土地利用/覆盖变化的数量和流向特征以及引起的生态系统服务价值动态特征。结果显示:巢湖流域近10年来土地利用整体特征并未发生重大改变,以耕地和水域为主,耕地面积减少最多,建设用地占用是巢湖流域耕地减少的主要原因。流域利用与土地覆盖类型在流向转移过程中,主要集中在耕地与其他地类的相互转化上。巢湖流域生态系统服务价值以2002年为界,大体分为两个阶段,水域和林地生态系统服务价值在变化过程中起决定性作用。除了巢湖市以外,其他地市生态系统总服务价值与该地市面积之间成统一关系。肥东县和无为县的生态系统服务价值变化最大,巢湖市2001年之前变化不明显。     

宁夏中卫市沙坡头区近13年土地利用空间布局变化及环境健康效应

以宁夏中卫市沙坡头区为研究区,综合分析了近13年来土地利用空间布局变化情况,获取了2000年8月、2007年8月和2013年8月三期的TM影像,运用Envi5.0遥感影像处理软件对其分析处理,并对三期的遥感影像进行监督分类,得到三个不同时期的土地利用分类数据。通过计算单一土地利用动态度,分析了不同研究时期各种土地利用类型的变化速度和转变方向,以及由此产生的环境健康效应。结果表明:研究区土地利用类型变化速度较快,土地利用空间布局变化较大,主要表现为水体、建筑用地、林地和草地面积大量增加,耕地、裸地和沙地面积不断减少,并且增减速度较快;环境健康效应是防沙固沙林带增加,退耕还林还草工程成果显著。     

北京市土地利用变化特征及驱动机制

以北京市为例,利用1985、2000和2010年三期土地利用数据,从土地利用变化幅度、土地利用变化速度、土地利用转移方向等方面,揭示了北京市1985—2010年的土地利用变化特征及相关驱动因子。结果表明:11985—2010年,北京市土地利用空间格局发生了较大变化,林地面积有一定程度的增加,耕地面积、水域面积减少较为迅速,建设用地扩张最为明显。21985—2000年,北京市土地利用综合动态度为0.99,土地利用变化速度较为平缓;2000—2010年,北京市土地利用综合动态度为1.64,土地利用类型变化速度呈加速趋势;从单一土地利用动态度来看,林地与建设用地的增加速度不断提升,由1985—2000年间的0.1383%、3.7808%增长到2000—2010年间的0.2078%、4.0088%;耕地、草地、水域面积不断减少,其中水域面积的减少速度最快。3从转移矩阵来看,1985—2000年,74.54%的耕地转化为建设用地,13.30%、11.24%的耕地转化为林地与水域;2000—2010年,耕地依然是各类用地增量的重要来源,建设用地向其他类型用地的转化面积是前一阶段的13.8倍。4从人口增长、经济发展、政府政策等方面研究了土地利用变化的驱动机制。     

Pleasure and belief in Hume's Decision Process

Abstract

The purpose of this paper is to introduce explicitly pleasure and belief in what aims at being a Humean theory of decision, like the one developed in Diaye and Lapidus (2005a). Although we support the idea that Hume was in some way a hedonist – evidently different from Bentham's or Jevons' way – we lay emphasis less on continuity than on the specific kind of hedonism encountered in Hume's writings (chiefly the Treatise, the second Enquiry, the Dissertation, or some of his Essays). Such hedonism clearly contrasts to its standard modern inheritance, expressed by the relation between preferences and utility.

The reason for such a difference with the usual approach lies in the mental process that Hume puts to the fore in order to explain the way pleasure determines desires and volition. Whereas pleasure is primarily, in Hume's words, an impression of sensation, it takes place in the birth of passions as reflecting an idea of pleasure, whose “force and vivacity” is precisely a “belief”, transferred to the direct passions of desire or volition that come immediately before action. As a result, from a Humean point of view, “belief” deals with decision under risk or uncertainty, as well as with intertemporal decision and indiscrimination problems.

The latter are explored within a formal framework, and it is shown that the relation of pleasure is transformed by belief into a non-empty class of relations of desire, among which at least one is a preorder.     

John Stuart Mill's Theory Of Justice

John Stuart Mill has traditionally been portrayed as self-contradictory and failing to construct a unified social theory. Recent scholarship, however, has challenged this view, finding Mill's work to be creatively synthetic in bridging the antinomies inherent in liberal democratic thought. This revisionist interpretation of Mill is advanced by an understanding of his theory of justice and its role in shaping his policy positions on issues such as welfare, education, voting rights, property rights, taxation, government intervention, and the future of capitalism.     

A Rich Vein for “Reality Mining”北大核心CSSCISSCI

Arik Hesseldahl In the aftermath of the September 11 attacks, U.S. officials quickly turned their attention to other potential targets, including California's Golden Gate Bridge. What would happen if terrorists took down the bridge between San Francisco and Marin County? How much of the region would be affected and for how long?     

Solidified Branding Function: How the Urban Brand Affects a Small Town’s Development? Case Study of Wangqingtuo,Tianjin, China

Chinese small towns are usually developed with single core industry,and the urban brand is the identity of a town that formed with the development of its indust...     

Nonlinearity in Stock Exchange Markets: The Case of Bist 100 Indices

In this paper,using data for the Bist 100 index,we investigate the presence of nonlinearities by employing several nonlinearity tests.The Brock,Dechert,and Sche...     

Globalization,Neoliberalism and the attack on social security

Neoliberal political movements advocate privatization of public pension systems. Globalization imposes pressure on nations to conform to neoliberal policy views with respect to the design and structure of social insurance, including public pension systems. The paper begins with an investigation of the economic, ethical and ideological dimensions of the privatization debates in the U.S.; it argues that privatization advocates may be largely moved by ideology, since the other reasons advanced appear weak or unfounded. The second part discusses the history of Social Security, the purposes for its creation, and some of its economic effects. Differences between public and private pension systems are considered. A brief international comparison of some aspects of public pension system finance and benefit structures is presented. The final section considers the ethical, macroeconomic and distributional implications of privatization, prefunding and payroll tax funding, and argues for a pay as you go system financed with income taxes. In order to promote equity, economic security, community, and social cohesion, public pension systems should be universal in coverage. In order to reduce the inequality, income insecurity, and aged poverty generated by market economies, public pension systems ought to be progressive: benefit/contribution ratios should be inversely proportional to income, and progressive income taxes should finance the system. To promote economic growth, the systems should be financed on a pay-as-you-go basis, and should not be prefunded except for an emergency reserve. The fiscal policy recommendations partially depend upon the theory developed by Abba Lerner in the 1940s, and recently advanced by Wynne Godley and Randy Wray: Lerner's “principle of functional finance.”     

Perspective on the Economic Evolution of the European Union States Under the Impact of the Pandemic and Financial-Economic Crisis

The European Union,which is at the beginning of its term of office for all Member States in the European Parliament,the European Commission,its governing body a...     

中国养活自己能力的长期预测:技术和政策分析

中国拥有世界五分之一强的人口 ,收入又在迅速增长。因此 ,国际上很自然地会考虑或推测她在今后的几十年是否有能力养活自己。中国的人口预计将从 2 0 0 0年的 1 2 8亿增长到 2 0 2 0年的 1 4 6亿 ,和 2 0 3 0年的 1 4 9亿。与此同时 ,人均收入的增长将导致对家畜和鱼类产品更大的需求 ,因而对饲料的需求也将有很大的增长     

Neurally reconstructing expected utility

While the concept of “expected utility” informs many theories of decision making, little is known about whether and how the human brain might compute this quantity. This article reviews a series of functional magnetic resonance imaging (FMRI) experiments designed to localize brain regions that respond in anticipation of increasing amounts of monetary incentives. These studies collectively suggest that anticipation of increasing monetary gains activates a subcortical region of the ventral striatum in a magnitude-proportional manner. This ventral striatal activation is not evident during anticipation of losses. Actual gain outcomes instead activate a region of the mesial prefrontal cortex. During anticipation of gain, ventral striatal activation is accompanied by feelings characterized by increasing arousal and positive valence. These findings affirm the role of emotion in the anticipation of incentives, and may provide an initial step towards a neural reconstruction of expected utility.     

Duplication, Growth and ‘Total Return Economics’

Maintenance consumption is an expense recovered in product prices, yet also a source of taste satisfaction which must be exhausted, rather than reinvested, from the capital affording it. This riddle is solved in the duplication rules: the cost of maintenance consumption is recovered in pay and prices, but an equal flow is exhausted from the human capital of the worker earning the pay. The rules impact tradition in several ways. If output is defined in principle as value added, then it cannot also be described as consumption plus net investment without double-counting the maintenance consumption recovered in prices. Also rate of return in the stationary state is not zero, but is the rate sufficient to offset the exhaustion of individual human capital. The rules lead to new insights into economic return, and support an argument that all growth at the scale of closure is due to productivity gain rather than to thrift.