Ecological suitability evaluation for urban growth boundary in red soil hilly areas based on fuzzy theory

The fuzziness exists in spatial distribution of geographic data of land suitability evaluation processes,which makes it difficult to quantify land boundaries by using traditional binary logic-based overlay model.Aiming at this limitation,an ecological suitability evaluation analysis model was presented based on fuzzy theory and a research on urban growth boundary(UGB) of the Great-Hexi Leading District(GHLD) of Changsha was conducted.With the support of GIS,RS and MATLAB,slope,elevation,vegetation,soil productivity,soil permeability,water body and land use are selected as the input of model according to the characteristic properties of soil and terrain in red soil hilly areas.The running result of this model indicates that the ratios of highly suitable land,suitable land,moderately suitable land and unsuitable land in GHLD are 18.75%,10.31%,64.16%,6.78%,respectively.This result accords with spatial structure worked out by Space Development Strategy Planning of GHLD,Based on this result,several suggestions are made to guide UGB developments in future.

Urban Green Space Planning Based on Computational Fluid Dynamics Model and Landscape Ecology Principle:A Case Study of Liaoyang City,Northeast China

As a result of environmental degradation,urban green space has become a key issue for urban sustainable development.This paper takes Liaoyang City in Northeast China as an example to develop green space planning using the computational fluid dynamics (CFD) model,landscape ecological principles and Geographical Information System (GIS).Based on the influencing factors of topography,building density and orientation,Shou Mountain,Longding Mountain and the Taizi River were selected as the urban ventilation paths to promote wind and oxygen circulation.Oxygen concentration around the green spaces gradually decreased with wind speed increase and wind direction change.There were obvious negative correlation relationships between the oxygen dispersion concentration and urban layout factors such as the building plot ratio and building density.Comparison with the field measurements found that there was significant correlation relationship between simulated oxygen concentration and field measurements (R 2=0.6415,p<0.001),moreover,simulation precision was higher than 92%,which indicated CFD model was effective for urban oxygen concentration simulation.Only less than 10% areas in Liaoyang City proper needed more green space urgently to improve oxygen concentration,mainly concentrated in Baitai and west Wensheng districts.Based on land-scape ecology principle,green space planning at different spatial scales were proposed to create a green space network system for Liaoyang City,including features such as green wedges,green belts and parks.Totally,about 2012 ha of green space need to be constructed as oxygen sources and ventilation paths.Compared with the current green space pattern,proposed green space planning could improve oxygen concentration obviously.The CFD model and research results in this paper could provide an effective way and theory support for sustainable development of urban green space.

Impacts of Suburbanization on Urban Eco-environment of Xi'an in China

Suburbanization in large cities is an important phenomenon in the process of urbanization development in China in recent decades,which plays a very important role in promoting city development,whereas some side effects on the eco-environment appeared at the same time.This paper,taking Xi'an City in China as a case study site,analyzed the features of population suburbanization and industry suburbanization and pointed out the impacts of suburbanization on urban eco-environment.Based on the research,suggestions of countermeasures for urban planning and municipal management of Xi'an City in protecting urban eco-environment and conserving natural ecology were put forward in the end.

Eco-budget-A Model of Urban Environmental Management

In this paper, a new model of urban environmental resource management is introduced. The article analyzes the gap between urban environmental management and the management of economy and human resources. The significance, the key points, the implementation procedures, and steps of eco-budget cycle are discussed.

Integrated Geo-information System for the Development of Low Carbon Eco-city in China Urban Context

Nowadays, cities are the main living environment of human beings. Rapid urbanization is associated with a variety of issues： population explosion, urban heat island effect, greenhouse gases emissions, energy crisis, climate change and so on. To deal with the challenges from the huge energy consumption and GHGs （greenhouse gases） emission, more and more attention has been paid to low carbon eco-city in China. In this research, the whole process is linked by low carbon eco-city development. High-resolution thermal IR （infrared） satellite remote-sensing is introduced to land use and urban heat island monitoring to meet the requirement of higher accuracy. GIS （geo-information science） technology provides a framework for collecting, processing, managing, analyzing and sharing spatial and temporal data. It has been used in spatial and temporal database management and analysis in low carbon eco-city study. The integrated geo-information system proposed in this research, which will be introduced to various government agencies in China, could enrich the concepts and means for the construction of low carbon eco^city.

On The Rational Dimension of Eco-city Construction

Reasonable ＂eco-city＂in the external between urban and rural areas should make a complete ecological cycle of the system, so that the internal energy efficiency and low pollution, resource use environmentally clean, quiet comfortable life of the people, as well as other elements of the organic： unity of urban greening. So, ＂Eco-City＂, ＂urban ecology＂ are two heterogeneous areas should be treated differently. However, in rural and urban dualistic situation, China advocated ＂ecological city＂ ignored the rural ecological balance, resulting in ＂eco-city＂development directly into＂ urban ecology＂ construction within the city along with the waste of resources, water pollution, serious problems of air pollution, noise pollution, the deep ＂eco-city＂ into representation＂ urban ecology＂, in the standard does not cover up the sound, making the generation between rural and urban＂ material Rift ,＂after all ,can not be filled.

Simulation and analysis for anthropogenic heat release

Heat balance of urban ecosystem is a key point for the study of urban climate and micro-climate pattern and its change mechanism. Urban heat island effect is becoming increasingly serious,which is mainly caused by the change of the earth's surface cover and the anthropogenic heat release. In this study,the simulation experiment for the anthropogenic heat release was designed according to the heat balance principle. A set of buildings of miniature city were used to constitute the residential area,U grooves were applied to simulate the single building,and the fluorescent lamps in the U groove were regarded as the heat sources of the anthropogenic heat release. The simulation experiment was launched with long-short wave sun photometer,sonic anemothermometer and heat flow gauge in the experiment site. Then the net solar radiation,sensible heat flux and heat flux into the ground were determined. The quantities of the anthropogenic heat release were calculated based on the heat balance principle,and were compared with the theoretical power consumption of the fluorescent lamps. The root mean square error( RMSE) of the simulation for the anthropogenic heat release reaches0. 078 W·m- 2,a comparatively high precision,which showes that the anthropogenic heat release can be accurately determined through the simulation experiments. This study provided a scientific method for the purpose of monitoring the anthropogenic heat release.

Questioning Ecosystem Assessment and Restoration Practices in a Major Urban Estuary： Perpetuating Myths of Degradation in Spite of the Facts

The Jamaica Bay ecosystem is a dichotomy. It encompasses more than 12,000 acres of coastal estuarine marshes and an ecological diversity rivaling any coastal environment in the world. It is considerably altered, and is affected by a variety of ecological insults directly related to the fact that more than 14 million people live in its vicinity. Environmental protection institutions responded to the challenge of protecting the bay, surrounding wetlands and recreational benefits by addressing the increasing load of contaminants into the ecosystem. Billions of dollars have been spent during the past five decades on restoration attempts, including upgrading wastewater treatment plantsand the closure of three major sanitary landfills. Even with the curtailment of untreated wastewater release and ending periodic dredging and filling programs, all activities that are necessary processes in maintaining an urban harbor, the Jamaica Bay ecosystem has reached a point where many believe it to be unrecoverable, requiring massive infusions of restoration dollars. This categorization has been perpetuated based on questionable data （the ＂myths＂） that, when investigated in rigorous scientific detail, prove to be unsubstantiated. In this paper, the origin of these myths and the scientific investigation that dispel them are discussed.

规划研究动态

生态城市与生态城市规划导言建设生态城市是城市发展的方向,生态城市规划则是生态城市建设的先导,本文从生态城市概念与标准入手,系统介绍了当前国内外生态城市规划与建设现状。

Rural Ecotourism: An Effective Way of Maintaining Indigenous Character in Rapidly Urbanizing Rural Areas: A Case Study of Five Golden Flowers in Chengdu, China

China is the largest developing country in the world and a well-known agricultural country. China＇s urbanization is a subject of great interest, one that has attracted the attention of people throughout the world. Whereas a handful of studies have assessed various aspects of urbanization（urban expansion, urban transition, urban-rural relationships, the spatial changes in urban and rural areas, motivations for sustaining rural places）, little is known of how to retain the indigenous character of rural areas in terms of landscape design. In this paper, the authors set out to contribute to this significant gap. They used Chengdu City and Five Golden Flowers（FGF） village in Chengdu＇s suburbs as case studies. A detailed description of the application of Ebenezer Howard＇s Garden City vision in Chengdu City was made; the Garden City vision was the key premise for FGF＇s ecotourism industry and successful conservation of landscapes with indigenous character. An analysis of the post-ecotourism landscape in FGF was accomplished using a typology method. Finally a set of landscape design methods for retaining indigenous character was proposed. The main conclusion of this paper was as follows： rural ecotourism can contribute to maintaining the indigenous character of rapidly urbanizing rural landscapes with the use of appropriate inheritance and renovation ways. The findings here may provide useful information for decision making by urban planners and policy-makers.