Effects of Increasing Urbanization on the Ecological Integrity of Open Space Preserves

This article analyzes the effects of increasing urbanization on open space preserves within the metropolitan area of Phoenix, Arizona, USA. Time series analysis is used in 10-year increments over 40 years to study urban landscape change. Three landscape metrics—(1) matrix utility (measures intensity of adjacent land uses), (2) isolation (measures distances to other open space patches), and (3) connectivity (measures physical links to other open space patches and corridors)—are used to assess changes in landscape patterns and serve as indicators of urban ecological integrity of the open space preserves. Results show that in the case of both open space preserves, general decline in indicators of urban ecological integrity was evident. The matrix utility analysis demonstrated that increasing intensity of land uses adjacent to preserve is likely to increase edge effects, reducing the habitat value of interior or core habitat areas. Isolation analysis showed that both preserves have experienced increasing isolation from other open space elements over time. Also, connectivity analysis indicated that terrestrial connections to other open space elements have also deteriorated. Conclusions of this research demonstrate that while preservation of natural areas as open space is important in an urban context, intense development of surrounding areas reduces the urban ecological integrity significantly.     

Variability in Population Abundance and the Classification of Extinction Risk

Abstract: Classifying species according to their risk of extinction is a common practice and underpins much conservation activity. The reliability of such classifications rests on the accuracy of threat categorizations, but very little is known about the magnitude and types of errors that might be expected. The process of risk classification involves combining information from many sources, and understanding the quality of each source is critical to evaluating the overall status of the species. One common criterion used to classify extinction risk is a decline in abundance. Because abundance is a direct measure of conservation status, counts of individuals are generally the preferred method of evaluating whether populations are declining. Using the thresholds from criterion A of the International Union for Conservation of Nature (IUCN) Red List (critically endangered, decline in abundance of >80% over 10 years or 3 generations; endangered, decline in abundance of 50–80%; vulnerable, decline in abundance of 30–50%; least concern or near threatened, decline in abundance of 0–30%), we assessed 3 methods used to detect declines solely from estimates of abundance: use of just 2 estimates of abundance; use of linear regression on a time series of abundance; and use of state‐space models on a time series of abundance. We generated simulation data from empirical estimates of the typical variability in abundance and assessed the 3 methods for classification errors. The estimates of the proportion of falsely detected declines for linear regression and the state‐space models were low (maximum 3–14%), but 33–75% of small declines (30–50% over 15 years) were not detected. Ignoring uncertainty in estimates of abundance (with just 2 estimates of abundance) allowed more power to detect small declines (95%), but there was a high percentage (50%) of false detections. For all 3 methods, the proportion of declines estimated to be >80% was higher than the true proportion. Use of abundance data to detect species at risk of extinction may either fail to detect initial declines in abundance or have a high error rate.     

Viewpoint Berlin: Strategic urban development in Berlin – Challenges for future urban green space development

Global changes such as climate change and demographic change next to a more diverse urban society and restricted municipal budgets represent significant challenges urban planning has to deal with today and in the near future. This viewpoint presents insights from urban planning on urban green and open space development and respective planning processes for the city of Berlin, Germany. An environmental development strategy – the Urban Landscape Strategy – is introduced and presented as a success story due to a number of reasons. These reasons include specific aspects related to strategy development, illustration and communication as well as the use of reference projects and implementation programs. Finally, the administrative structure which combines urban planning and green and open space planning in one joint department is shown to significantly contribute to positive planning processes for the entire city.     

海岸带国土空间开发适宜性评价及功能空间配置——以海南岛为例

海岸带国土空间开发适宜性评价及功能空间布局优化是推进陆海统筹战略目标的科学基础。以海南岛为例,基于环境损益分析思想构建海岸带“潜力—限制”评价指标体系,综合运用多要素乘积及空间叠置等方法,对海南岛海岸带地区的国土空间开发建设适宜性进行集成评价,并依据功能空间判别条件识别“港—工—城”区、滨海旅游区、农林牧渔区以及自然保护区四类海岸带功能空间。研究表明：海南岛海岸带国土空间开发适宜区总体呈现“西岸多,东岸少”的空间分布格局,适宜、基本适宜、基本不适宜、不适宜建设区面积依次为1785.32 km²、1724.57 km²、812.86 km²、4051.67 km²,适宜区与不适宜区重叠交错,给海岸带国土空间开发带来巨大压力。海岸带地区四类功能空间面积依次为1813.39 km²、2138.26 km²、1831.62 km²和2591.15 km²,分别占海岸带面积的21.65%、25.53%、21.87%和30.94%,海岸带的功能空间呈现“一环”“两极”和“多点”的空间格局。依据归纳出的三类典型功能空间冲突,对功能空间进行了调整优化,增强了各类功能空间的集聚性和连通性,但仍存在海域与陆域的相同功能空间不连片,海陆经济联系不够通畅,相互支撑不足等问题,国土空间开发还存在较多的陆海矛盾和冲突。研究结果指明了各类适宜性等级区域的开发或保护模式,丰富了适宜性的应用条件,也是对国土空间开发适宜性评价的适当拔高。     

国土空间规划视角下海洋空间用途管制的关键问题思考

通过对用途管制的概念比较和内涵延伸分析,明确了海洋空间用途管制的核心内容为规划分区与管制规则。规划分区应具有“区域、边界、用途、使用条件”四个基本属性,并以科学认知海洋的客观属性及演变规律为基础,故基于“双评价”客观认知海洋空间的功能或用途是规划分区的关键。海洋空间用途管制面临的四个基本问题是“如何保护”“如何利用”“如何在保护中利用”“如何在利用中保护”。进而,以“双评价”为基础,构建开发保护二维坐标系,明确海洋空间用途管制的政策取向与内容导向。其中,海洋生态空间管制宜采用“分级+分类”的管制方式,海洋开发利用空间宜采用“分区管理+用海准入”的管制方式。     

农村建设用地整治的空间生产机制及其效应——以广东省窑塘村为例

从空间生产视角介入,结合行动者网络理论和利益相关者分析方法,构建“空间生产过程—空间生产机制—空间生产效应”的研究框架,通过深度访谈收集一手数据,对广东省窑塘村建设用地整治进行深入剖析,阐释其空间生产过程、机制及效应。结果表明：（1）关键行动者镇政府和核心行动者党群理事会积极征召和动员,各行动者为满足自身利益诉求通过“闲置危旧集体拆,社区产业联合建”的强制通行点构建行动者网络,完成农村建设用地整治空间生产过程。（2）窑塘村建设用地整治空间生产以土地增值为内动力,释放土地发展权的交易价值、经营价值和生产价值,以利益相关者追求利益最大化为外动力,内外动力共同作用形成空间生产机制。（3）村集体合理配置土地发展权,积极推进村庄建设和产业发展,利用外力驱动乡村内生动力,引导城乡要素形成“二次流动”,为乡村物质空间生产带来正面效应;但在农村建设用地整治和新村建设中,小部分农民的居住权益被忽视,导致空间隔离现象产生,对乡村社会空间生产造成了负面效应。     

淮河流域洪涝变化的混沌特征

从功率谱结构,Ｌｙａｐｕｎｏｖ指数,吸收子维数和可预报时间等方面分析了淮河流域洪涝变化的混沌性质,研究表明淮河流域洪涝变化是一类混沌变化序列,洪涝系统是一类混沌为动力系统,系统时初值极端敏感,长期和不可预测,其可报预时间约为５－６年。     

中国北方地区沙尘暴变化趋势初探

沙尘暴是一种重要的环境问题和自然灾害，是土地沙漠化程度的重要指标。本文利用１９５１～１９８０年的整编气候资料、１９８１～１９８７年中国地面气象记录月报资料和１９９３～１９９４年的两个沙尘暴个例资料，对我国北方地区沙尘暴的空间分布和时间变化及其成因作了初步探讨，并对未来的变化趋势进行了初步预测。结果表明：沙尘暴主要发生在我国西北地区，且有两个多发中心区，即塔无拉玛干沙漠的西南部和甘肃河西走廊东部。沙尘暴主要发生在春季，尤以四月份最多；沙尘暴的形成是地形、地表沙尘物质、有利的急浪位置、低层大气的不稳定和锋面过境后的大风五种基本因素相互作用的结果；就整个北方地区而言，１９５１～１９８７年沙尘暴出现日数总的趋势是波动式减少的，但不同干旱气候区略有差异；本世纪末到下世纪中叶，整个北方地区沙尘暴总的趋势将呈波动式增加（约比１９５１～１９８７年的平均值增加７％）。     

基于WRF-Chem模拟验证的天水市主城区大气污染源排放清单

通过部门调研、现场调查和遥感解译等方法获取天水市主城区大气污染源活动水平数据,采用排放因子法估算了天水市主城区 10类污染源的9种污染物排放量,构建了2019年天水市主城区高分辨率排放清单,并采用横向比较法和模式验证法评估了排放清单的合理性.结果表明:(1)2019年天水市主城区 SO2、NOx、CO、VOCs、NH3...     

生活空间重构旅游者的乡村游憩影响因素与路径——一个模糊集的定性比较分析

旅游者是乡村旅游发展中的核心要素,但当前研究缺乏从城乡空间转换中的人地关系变迁角度对旅游者进行的思考。以经历城乡生活空间重构的旅游者为研究对象,运用分析多变量交互作用的模糊集定性比较分析方法,探索旅游者乡村游憩影响因素的复杂路径。研究发现:地方情感、怀旧情感、主观规范、知觉行为控制、态度、愿望（欲望）、旅游目的地知名度形成的128种组合中,其中有8个充分性条件构型特定组合路径能够影响乡村旅游者游憩行为;单项中地方情感、怀旧情感、知觉行为控制的一致性相对较高,但都不能构成旅游者乡村游憩影响因素的必要条件;8条旅游者乡村游憩行为影响因素路径条件组合的总体覆盖率约为0.918919,总体一致性约为1,均达到了0.9的阈值标准。其中,地方情感和怀旧情感特性是最关键的影响因素;旅游者具有地方情感、怀旧情感特征时,其他影响因素都可能在“特定情境”下发挥作用。据此提出了生活空间重构旅游者的乡村游憩影响路径模型,揭示了“乡村情感—游憩意向路径”“计划行为—游憩意向路径”“游憩愿望路径”和“情感行为综合路径”四类影响路径的作用机制。旅游从业者可以据此寻找与旅游者游憩最匹配的产品开发解决方案。