Comprehensive analysis of changes to catchment slope properties in the high-sediment region of the Loess Plateau, 1978-2010

To control soil erosion and restore the degraded environment in the Loess Plateau, a large number of measures related to soil and water conservation have been employed that have profoundly affected catchment properties. This study constructed three indicators to characterize changes to the catchment slope, proposed both a method for a regression analysis of adjacent images and a sequence model, and applied multisource remotely sensed images and GIS spatial clustering analysis technologies to extract thematic information and comprehensively analyze the catchment change characteristics. The results indicate that the catchment slope properties changed significantly. At catchment scale, the average values of ARC, DVC and ART were 6.43%, 25.57% and 4.30%, respectively. There were six clustering types of catchment slope property changes. The maximum and minimum of the average similarities of the clustering types were 0.992 and 0.935. Each slope control measures had a distinct effect on catchment slope; the dominating factor of each clustering type was identified as: Type 1: D-VC, Type 2: D-VCLU, Type 3: D-LUVC, Type 4: D-TAVC, Type 5: D-TAC and Type 6: D-MFC. Type 5 and Type 1 covered the largest areas, respectively occupying 37.28% and 31.01%. Catchment slope property changes also had distinct types that depended on their geomorphological conditions. These findings provide a useful basis from which to further study catchment slope hydrological and soil erosion processes.     

中国旅游科技创新的时空结构、重心轨迹及其影响因素研究

旅游产业是充满众多科技创新与成果转化的社会经济部门。以我国旅游产业相关发明专利、旅游收入、风景名胜区、高校学生数等为分析依据,基于地理集中指数、动态变动指数、空间重心模型和灰色关联分析等方法,对各省区2006—2017年旅游科技创新的时空结构、重心轨迹及其影响因素等进行实证研究。结果表明：时间上,我国旅游科技创新整体上呈波动上升的发展态势,2013年后地理集中度指数开始持续下降;空间上,旅游科技创新在我国呈东高西低、南高北低的分布格局。此外,旅游科技创新的空间重心位于我国华东地区,并呈先由北向南、再由东向西的移动轨迹。最后,科技创新产出、旅游经济水平、科技经费投入、经济宏观环境、科技创新服务、旅游资源禀赋等要素指标均对我国旅游科技创新产生一定影响,但影响程度具有差异。     

The transition from people''s property to private property: Consequences of the restitution principle for urban development and urban renewal in East Berlin''s inner-city residential areas

The constitutional decision to return to their original owners all real-estate property in East Germany that had either been expropriated or placed under state administration (the restitution principle) has had significant consequences for urban development and urban renewal. Experiences from East Berlin's innercity residential areas illustrate the effects on the state of repair of housing, the character of residential neighbourhoods, the tenants living in the areas affected, and the future structure of real-estate ownership. The case studies reveal a picture of a contradictory development of residential neighbourhoods, including shifting power relations and new polarizations, especially between tenants and landlords.     

改造华家岭防护林带的土壤改良效果

为探讨华家岭低效防护林带改造对土壤的改良效果,在华家岭地区选取生长不良的低效杨树纯林和改造后的云杉纯林、云杉×杨树、云杉×油松、云杉×落叶松混交林5种典型林带类型,对其土壤理化性状进行对比研究。结果表明:（1）云杉纯林及其混交林土壤的平均容重、平均毛管孔隙度、总孔隙度、通气度与杨树纯林的差异显著（p<0.05）,经过低效林改造后的云杉纯林及其混交林较杨树纯林的土壤容重有所下降,孔隙度和通气性有所提高\.（2）除速效P外,各林型的土壤速效N、速效K、全N、全P、全K和有机质含量随土层深度的增加而降低;云杉纯林及其混交林的土壤有机质含量、速效N、P、K和全量N、P、K养分均高于杨树纯林,pH值低于杨树纯林\.（3）云杉纯林及其混交林的有机质含量和全N含量与容重和总孔隙度的相关性较杨树纯林的好,云杉纯林及其混交林对土壤理化性能的改良作用优于杨树纯林。     

The Effects of Informal Settlement on Suburban Property Values in Cape Town,South Africa

During the late 1980s some informal settlements were established within or near affluent Cape Town suburbs. Despite objections by suburban residents that these settlements would lead to a rapid escalation in crime and a dramatic fall in the value of properties, the authorities allowed the settlements to remain. Using data on property transfers, which are then mapped using GIS, the paper examines the effects that the informal settlement of Marconi Beam had on house prices and housing turnover within the adjacent suburb of Milnerton. The results show that most of the objections regarding Marconi Beam's effect on property values were groundless as the settlement had only a negligible effect on property values in the adjacent suburb.     

Titles Of Theses

This essay questions the effectiveness of nuclear winter modeling as a means of impacting nuclear policy and changing public attitudes about nuclear issues. In nuclear winter modeling, humanistic concern over the possibility of global environmental destruction is cloaked in the ostensibly neutral language of science. Nuclear winter modeling attempts to apply rational argument to an issue that is rooted instead in human affect and morality. The implications of this misappropriation are discussed in terms of the dehumanizing nature of the images conjured up by nuclear winter, its attention to the effects of nuclear weapons rather than deeper structural problems, and its political ambiguity as a function of unresolvable uncertainty in model results.     

土壤保水剂的吸水保水性能研究动态

土壤保水剂是一种新型化学农业抗旱材料, 在干旱地区农林业生产中具有广泛的应用前景。从保水剂的吸水和保水性能方面介绍了国内外学者的研究成果。     

西北地区降水对陆面特征敏感性的数值试验

本文是一个用大气环境模式研究中国西北地区陆面特征改变之后影响其降水的数值试验，模式中假定西北地区的植被完全被裸陆代替，对６、７、８月进行数值积分，以便检查夏季大气环流对陆面特征的响应，数值试验的结论是：陆面反照率升高后，与之相伴随的是降水率下降，并且大气的下沉运动控制了该地区。     

快速城市化下 "转型社区"空间改造的障碍——广州、深圳案例

城中村在土地利用、建设景观、规划管理、社区文化等方面均表现出强烈的城乡差异及矛盾。近年来,我国部分地区采取了"转制"的措施来消除"城中村"的城乡二元结构,形成了兼具城市与乡村社区特征的"转型社区",——人口由农民转为市民、土地由集体所有转为国有、经济由集体经济转为股份公司、管理由村委会转居委会——其空间改造也提上日程。从"转型社区"的土地利用问题出发,介绍目前常用的"转型社区"改造模式,并分别从"转型社区"内土地产权和使用主体分析转制后依然存在甚至加剧的改造障碍。研究认为,土地的伪国有化定义下的不完全产权、土地非法与合法混杂导致的用地破碎化和现有利益格局下各土地利用主体的成本与收益失衡导致"转型社区"内公共设施缺乏、土地价值过低且被过度利用的状态难以改变。以此为基础,提出了对"转型社区"改造的建议。     

我国生态城市建设的时代意义、科学理念和准则

生态城市建设是顺应世界生态潮流,促进我国城市可持续发展的必然道路,具有重大的时代意义。应树立生态城市建设是实现城市可持续发展的唯一战略选择的科学理念,明确生态城市建设的宗旨和要务,抓住城市地域空间这个关键,实施城市开放空间系统的优化。我国生态城市建设应遵循城市-区域生态系统整体优化、生态城市建设与经济社会发展相协调、社会生产力的发展推动生态城市建设、以人为本和利益公平,以及坚持区域创新等科学准则。