城市地下空间开发中的弃土管理和处置对策

城市地下空间的大规模开发利用将产生大量弃土。简要分析了弃土对环境的影响,介绍了弃土管理和处置的现状以及存在的问题,提出了加强立法和管理、优化施工方法和技术、对弃土进行资源化利用、妥善处置已污染的弃土等对策。     

农村面源污染治理的政策与管理服务体系优化——以上海郊区农村为例

农村面源污染控制不仅是技术问题,也是管理体制与机制问题,探讨并完善农村面源污染治理的政策、管理与服务体系已成为当前研究的热点与难点。以上海郊区农村为例,梳理总结农村面源污染及其控制现状;在肯定当前治理效果的同时,识别其局限性,指出农业政策与环境保护政策的不协调、农村发展模式转变下制度与服务体系的相对滞后是根本原因;针对当前农村面源污染重要的贡献者——化肥、农药、畜禽粪便以及农村生活污水,分别从改革农业补贴制度、重构实现农村多重价值的制度以及完善农业生产服务体系等方面给出了治理的对策与建议。     

加油站地下储油罐压力管理系统的相关研究

在当前普遍采用的加油站真空辅助式第二阶段油气回收系统中,为了避免回收到地下储油罐中的油气再次通过P/V阀排空,必须对其中气相空间的压力实施有效控制。从国外的发展情况来看,地下储油罐的压力管理系统主要分为基于膜分离技术、基于弹性气囊和基于活性炭吸附三大类,其中膜法油气回收装置在国内已经得到了较多关注。首次系统介绍了气囊式压力管理系统的工作原理及其主要结构设计,具体包括管线布局、钢制压力容器壳体、位于容器顶部封头上的接口组件和全部位于容器内的气囊等;同时对另外一种可行方案进行了分析。     

Comparative capitalism and sustainable development: Stakeholder capitalism and co-management in the Kenyan fisheries sub sector

This paper argues that stakeholder capitalism is more appropriate to natural resource management and rural development in Africa than other varieties of capitalism. It examines different management arrangements in Kenyan Lake Victoria fisheries resources to argue that whilst stakeholder capitalism is still far from being the mainstream model of capitalism in Kenya, theoretically and empirically, it is more appropriate to sustainable development than the Anglo‐Saxon variety of capitalism that the country inherited from its British colonizers. The paper demonstrates that the concepts of ownership and management rights are social, economic and political constructs that are continuously contested, with huge implications for sustainable development and natural resource management.     

Assessment of the Enabling Rural Innovation (ERI) approach: Case studies from Malawi and Uganda

This paper presents lessons from applying an innovative action research approach for linking smallholder farmers to markets, in eastern and southern Africa. The Enabling Rural Innovation (ERI) approach aims to strengthen social organization and entrepreneurial capacity in rural communities. It focuses on fostering community‐based capacity for the inclusion of rural women and the poor in analyzing and accessing market opportunities. Using case studies from Malawi and Uganda the paper assesses the outcomes of ERI on rural communities with a focus on human capital, gender issues and investment in natural resource management. Results show that households are benefiting significantly from linkages to markets in terms of increasing household incomes, and accumulating assets. Skills in analyzing markets and in negotiating with traders have increased among smallholder farmers. The integration of gender in the approach has led to changes in gender decision making patterns at household and community level towards a more shared decision‐making process. The results however show a difference in skills between men and women, with women showing lower levels of skills acquisition. Farmer participatory research has increased investments in improved technologies such as fertilizer applications for soil fertility management.     

The Influence of Proximity to a National Forest on Emotions and Fire-Management Decisions

Because American national forests are managed for all citizens, it is important that researchers explore the differences and similarities between citizens living both near and far from publicly managed land. We surveyed residents living at various distances from nationally managed land to collect resident perceptions of different forest fire-management techniques, to determine public preferences for these techniques, and to examine the motivations behind these preferences. Participants both close to and far away from national forests tended to favor a multipronged approach to fire management by preferring the use of a combination of two or more fire-management techniques. There were no significant differences by proximity in participants’ self-rated emotions, types of fire-management techniques preferred, or the reasons and rationales for their preferred fire-management technique(s), indicating that the proximity variable may not be as significant as previously thought.     

Streambank Soil and Phosphorus Losses Under Different Riparian Land‐Uses in Iowa1

Abstract: Phosphorus and sediment are major nonpoint source pollutants that degrade water quality. Streambank erosion can contribute a significant percentage of the phosphorus and sediment load in streams. Riparian land‐uses can heavily influence streambank erosion. The objective of this study was to compare streambank erosion along reaches of row‐cropped fields, continuous, rotational and intensive rotational grazed pastures, pastures where cattle were fenced out of the stream, grass filters and riparian forest buffers, in three physiographic regions of Iowa. Streambank erosion was measured by surveying the extent of severely eroding banks within each riparian land‐use reach and randomly establishing pin plots on subsets of those eroding banks. Based on these measurements, streambank erosion rate, erosion activity, maximum pin plot erosion rate, percentage of streambank length with severely eroding banks, and soil and phosphorus losses per unit length of stream reach were compared among the riparian land‐uses. Riparian forest buffers had the lowest streambank erosion rate (15‐46 mm/year) and contributed the least soil (5‐18 tonne/km/year) and phosphorus (2‐6 kg/km/year) to stream channels. Riparian forest buffers were followed by grass filters (erosion rates 41‐106 mm/year, soil losses 22‐47 tonne/km/year, phosphorus losses 9‐14 kg/km/year) and pastures where cattle were fenced out of the stream (erosion rates 22‐58 mm/year, soil losses 6‐61 tonne/km/year, phosphorus losses 3‐34 kg/km/year). The streambank erosion rates for the continuous, rotational, and intensive rotational pastures were 101‐171, 104‐122, and 94‐170 mm/year, respectively. The soil losses for the continuous, rotational, and intensive rotational pastures were 197‐264, 94‐266, and 124‐153 tonne/km/year, respectively, while the phosphorus losses were 71‐123, 37‐122, and 66 kg/km/year, respectively. The only significant differences for these pasture practices were found among the percentage of severely eroding bank lengths with intensive rotational grazed pastures having the least compared to the continuous and rotational grazed pastures. Row‐cropped fields had the highest streambank erosion rates (239 mm/year) and soil losses (304 tonne/km/year) and very high phosphorus losses (108 kg/km/year).     

Determination of Impact of Urbanization on Agricultural Land and Wetland Land Use in Balçovas’ Delta by Remote Sensing and GIS Technique

Because of their intense vegetation and the fact that they include areas of coastline, deltas situated in the vicinity of big cities are areas of greet attraction for people who wish to get away from in a crowded city. However, deltas, with their fertile soil and unique flora and fauna, need to be protected. In order for the use of such areas to be planned in a sustainable way by local authorities, there is a need for detailed data about these regions. In this study, the changes in land use of the Balçova Delta, which is to the immediate west of Turkey’s third largest city Izmir, from 1957 up to the present day, were investigated. In the study, using aerial photographs taken in 1957, 1976 and 1995 and an IKONOS satellite image from the year 2005, the natural and cultural characteristics of the region and changes in the coastline were determined spatially. Through this study, which aimed to reveal the characteristics of the areas of land already lost as well as the types of land use in the Balçova delta and to determine geographically the remaining areas in need of protection, local authorities were provided with the required data support. Balçova consists of flat and fertile wetland with mainly citrus-fruit orchards and flower-producing green houses. The marsh and lagoon system situated in the coastal areas of the delta provides a habitat for wild life, in particular birds. In the Balçova Delta, which provides feeding and resting for migratory birds, freshwater sources are of vital importance for fauna and flora. The settlement area, which in 1957 was 182 ha, increased 11-fold up to the year 2005 when it reached 2,141 ha. On the other hand, great losses were determined in farming land, olive groves, forest and in the marsh and lagoon system. This unsystematic and rapid urbanization occurring in the study region is not only causing the loss of important agricultural land and wetland, but also lasting water and soil pollution.     

Information technologies and the sharing of disaster knowledge: the critical role of professional culture

A comparative survey of a diverse sample of 96 US and Italian emergency management agencies shows that the diffusion of new information technologies (IT) has transformed disaster communications. Although these technologies permit access to and the dissemination of massive amounts of disaster information with unprecedented speed and efficiency, barriers rooted in the various professional cultures still hinder the sharing of disaster knowledge. To be effective the available IT must be attuned to the unique settings and professional cultures of the local emergency management communities. Findings show that available technology, context, professional culture and interaction are key factors that affect the knowledge transfer process. Cultural filters appear to influence emergency managers' perceptions of their own professional roles, their vision of the applicability of technology to social issues, and their perspective on the transferability of disaster knowledge. Four cultural approaches to the application of IT to disaster communications are defined: technocentric; geographic,; anthropocentric; and ecocentric.     

Relation of waste generation and composition to socio-economic factors: a case study

To develop an effective waste management strategy for a given region, it is important to know the amount of waste generated and the composition of the waste stream. Past research has shown that the amount of waste generated is proportional to the population and the average mean living standards or the average income of the people. In addition, other factors may affect the amount and composition of waste. These are climate, living habits, level of education, religious and cultural beliefs, and social and public attitudes. This paper presents the findings of a study carried out in a suburban municipal area in Sri Lanka to determine the solid waste generation rate and waste composition based on field surveys and to determine the related socio-economic factors. A database was developed that included information on the quantity and composition of waste generated in a sample of households in the study area over a time period. The collected data was analysed to relate waste generation and composition data to various socio-economic factors. Over 400 sample households were selected for the study using a stratified random sampling methodology based on municipal wards and property values. A technique that considers both the number of households in a particular income group (property value range) and the standard deviation of property values within a given income group was used to determine the appropriate sample size for each municipal ward. Through category and regression analyses, the quantities of waste and waste composition were related to several socio-economic factors. The paper describes the basis for the sample selection, the methodology adopted for data collection, the socio-economic parameters used for the analysis, and the relationships developed from the analysis.