Planning for green cities: some emerging principles

There are a number of reasons why planners should take a more positive approach towards the natural economy of the city, and this paper rehearses the arguments in favour. The author takes the view that much publicly owned land is manicured and excessively stocked with exotic species so that they are relatively poor in wildlife. An alternative to the generally held view that dormant land in urban areas is unsightly and encourages vandalism, is that such sites offer opportunities for visual interest, education and recreation. The paper concludes by outlining a number of courses of action which, it is suggested, may come to dominate environmental planning.     

1986～2015年棋盘山水库湿地保护地生态系统演变分析

为探讨沈阳市棋盘山水库湿地保护地近30年生态系统演变规律,文章运用3S技术和景观格局指数,分析了保护地1986~2015年生态系统时空变化及景观格局演变特征。结果表明:1986~2015年间,由于人类活动的干扰,保护地景观破碎度和空间异质性不断增加,水库周边建设用地围绕水库向南部、北部不断扩张,不利于生态系统服务功能的保护和提升,但总体上看,2000~2015年人类活动强度低于1986~2000年,说明该时期生态保护工作取得一定成效。为提升保护地景观质量和生态系统服务功能,提出了保护地生态系统服务可持续管理对策。     

融雪剂对园林植物种子萌发的影响

使用融雪剂是高纬度城市冬季除雪的主要措施之一,但融雪剂中含有的盐类物质可以对园林植物造成伤害。在此研究了融雪剂对刺（Robinia pseudoacacia）、万寿菊（Tagetes erecta）、矮紫薇（Lagerstroemia indiea’Petite pinkie＇）、草地早熟禾（Poa pratensis）、侧柏（Platycladus orientalis）种子发芽率和相对受害率的影响。试验结果表明：5种植物种子的发芽率随融雪剂浓度的升高而降低．相对受害率则随融雪剂浓度升高而增大。其中草地早熟禾种子时融雪剂最敏感,可以用草地早熟禾种子萌发为指示,间接检验融雪剂对植物的伤害程度。     

城市景观水体中腐殖酸的臭氧氧化去除

以南京师范大学德风园池底泥中提取的腐殖酸(HA)为研究对象,采用臭氧氧化技术对其进行去除,对初始pH值、混合气体流量、腐殖酸(HA)初始浓度以及水中常见离子等因素对去除效果的影响进行了研究。实验结果表明:腐殖酸(HA)的去除率随初始pH值的升高而提高,随混合气体流量减少而提高;当腐殖酸(HA)初始浓度为5 mg/L时,反应过程中溶液的UV254升高,紫外扫描结果发现,溶液在200~220 nm内出现杂乱的吸收峰,表明有新物质生成;水中常见的无机阴离子(CO32-、HCO3-)和二价金属离子(Ca2+、Cu2+)的存在会降低臭氧对腐殖酸(HA)的去除率。     

Cadaver decomposition in terrestrial ecosystems

A dead mammal (i.e. cadaver) is a high quality resource (narrow carbon:nitrogen ratio, high water content) that releases an intense, localised pulse of carbon and nutrients into the soil upon decomposition. Despite the fact that as much as 5,000 kg of cadaver can be introduced to a square kilometre of terrestrial ecosystem each year, cadaver decomposition remains a neglected microsere. Here we review the processes associated with the introduction of cadaver-derived carbon and nutrients into soil from forensic and ecological settings to show that cadaver decomposition can have a greater, albeit localised, effect on belowground ecology than plant and faecal resources. Cadaveric materials are rapidly introduced to belowground floral and faunal communities, which results in the formation of a highly concentrated island of fertility, or cadaver decomposition island (CDI). CDIs are associated with increased soil microbial biomass, microbial activity (C mineralisation) and nematode abundance. Each CDI is an ephemeral natural disturbance that, in addition to releasing energy and nutrients to the wider ecosystem, acts as a hub by receiving these materials in the form of dead insects, exuvia and puparia, faecal matter (from scavengers, grazers and predators) and feathers (from avian scavengers and predators). As such, CDIs contribute to landscape heterogeneity. Furthermore, CDIs are a specialised habitat for a number of flies, beetles and pioneer vegetation, which enhances biodiversity in terrestrial ecosystems.     

视觉影响评价技术研究与应用

文章首先对于国内外出现的视觉影响评价与景观影响评价的概念进行了对比分析，提出“视觉影响评价”在功能表述上更为确切，并给出了视觉影响评价的基本概念，然后针对视觉影响评价的特点，介绍了视觉模拟用以预测影响的手段以及评价方法和减缓措施，并通过一具体实例进行了说明，最后针对我国视觉影响评价的现状提出了一些加强和改善的建议。     

Grouping Lakes for Water Quality Assessment and Monitoring: The Roles of Regionalization and Spatial Scale

Regionalization frameworks cluster geographic data to create contiguous regions of similar climate, geology and hydrology by delineating land into discrete regions, such as ecoregions or watersheds, often at several spatial scales. Although most regionalization schemes were not originally designed for aquatic ecosystem classification or management, they are often used for such purposes, with surprisingly few explicit tests of the relative ability of different regionalization frameworks to group lakes for water quality monitoring and assessment. We examined which of 11 different lake grouping schemes at two spatial scales best captures the maximum amount of variation in water quality among regions for total nutrients, water clarity, chlorophyll, overall trophic state, and alkalinity in 479 lakes in Michigan (USA). We conducted analyses on two data sets: one that included all lakes and one that included only minimally disturbed lakes. Using hierarchical linear models that partitioned total variance into within-region and among-region components, we found that ecological drainage units and 8-digit hydrologic units most consistently captured among-region heterogeneity at their respective spatial scales using all lakes (variation among lake groups = 3% to 50% and 12% to 52%, respectively). However, regionalization schemes capture less among-region variance for minimally disturbed lakes. Diagnostics of spatial autocorrelation provided insight into the relative performance of regionalization frameworks but also demonstrated that region size is only partly responsible for capturing variation among lakes. These results suggest that regionalization schemes can provide useful frameworks for lake water quality assessment and monitoring but that we must identify the appropriate spatial scale for the questions being asked, the type of management applied, and the metrics being assessed.     

An ecological planning model

In this article a model is proposed that could be used as a basis for ecological planning of natural resources. The role of people as part of the ecosystem is emphasized, and the various factors that should be considered in such planning are discussed. An understanding of ecological planning is dependent on the study of human activities in, and the nature of, natural ecosystems. It also depends on the fact that people are a part of nature, and as a result nature is of value to humans. Realizing the importance of this principle is a prerequisite to studying nature and also for an understanding of the various steps in the ecological planning approach. Realization of these values is often through a series of activities that may result in a negative environmental impact. Nature is described as an interacting group of natural features and processes. In this study both the features and processes are described as natural resources. The use of these natural resources obviously affects them, and if this use is to continue over a long period, both the activity and the resource must be understood if they are to be maintained in a productive state. In order to limit impact and maintain value, a planning aid called zoning is used to assist in the understanding of the processes involved.     

An early warning method of landscape ecological security in rapid urbanizing coastal areas and its application in Xiamen, China

Based on the Pressure-State-Response (P-S-R) approach, an index system for landscape ecological security (LES) was suggested using three dimensions, six factors, and three weights. The indicators in the system were divided into two groups: spatial interpolation (acquired by the remote sensing data) and non-spatial interpolation (acquired by consultation with experts). According to data of 2003 and 2006, coupled with current tendencies, the early warning method was classified into four categories: security and degradation, sub-security and slow degradation, sub-security and rapid degradation, and insecurity. Our research with early warning method finds three interesting phenomena: (1) mean value of LES in 2003 was 0.586, indicating medium security; while in 2006 it was 0.650, an upper medium security. The LES level within each districts of Xiamen in 2006 was better than the level in 2003. In terms of LES, the comprehensive condition within each district of Xiamen in 2006 was enhanced compared with 2003. Overall, there was improvement in 80.5% of areas from 2003 to 2006, showing promising signs of positive development. (2) The LES of Xiang’an District and Jimei District were in stages of high early warning given that the percentage of land in these districts that showed symptoms of insecurity and degradation was 41.03 and 34.89%, respectively. (3) On the whole, the areas that showed notable signs of insecurity and rapid landscape, and which can already be identified as early warning areas requiring immediate attention, correspond closely with the distribution of coastal industrial parks in these regions. In conclusion, the consequences of rapid industrialization and urbanization are far reaching and affect local and regional ecological security.