污水土地处理系统中管网铺设率对流态的影响与CFD模拟

污水土地净化系统的水力特性直接影响污染物的处理效果,研究不同管网铺设率对水流流态的影响,可为设计参数的选择及反应器结构优化提供依据.因此,运用示踪-应答技术,以停留时间分布(RTD)理论为基础,对反应器中水流的状态进行分析.同时,借助计算流体力学(CFD)软件Fluent进行数值模拟.RTD分析和CFD模拟结果互补分析发现,底部的碎石层具有布水功能,而表面的水层具有集水的作用:水流在承托层中水平流动,竖直流经填料层,最后在水层中水平流入集水管网.在有承托层和水层的情况下,系统采用不同管网铺设程度的布水和集水方式对填料中水流的流态影响不大,然而管网孔口布水效果不均.各管网铺设率反应器的体积效率均在90％以上,但都有一定的无效体积或滞留区.半网布水、集水的反应器体积效率最高,流态接近推流形式.无因次平均停留时间为1.09,轴向扩散系数为0.037.     

三槽氧化沟内底推位置与积泥厚度的分析研究

氧化沟工艺由于进水中含有大量的无机颗粒,无机颗粒的沉淀导致沟内积泥较厚。为了不影响正常生产,依据经验数据,依次对1号、2号氧化沟安装底推。对沟内积泥情况及影响因素进行分析比较,得出氧化沟的积泥主要由进水中密度较大的无机颗粒造成,且积泥规律与底推安装位置和运行情况相关。     

昆明市主城区三种温室气体的月份和干、湿季的小时变化规律及原因分析

研究了昆明市主城区3种温室气体浓度的最新变化情况,采用2009年、2010年和2011年的月份和小时平均浓度数据,结合昆明市气候特点,对3种温室气体浓度的月份和干、湿季的小时变化规律及原因进行了分析。     

Integrating ecosystem services evaluation and landscape pattern analysis into urban planning based on scenario prediction and regression model

ABSTRACT

Urban planning has become a widely concern for minimizing the negative effects of urban expansion on terrestrial ecosystems. We developed an interdisciplinary modeling framework to evaluate the effectiveness and shortcomings of urban expansion management strategies. A three-step method was applied to Yinchuan Plain in the northwestern of China, including (1) analyzing the relationship between landscape pattern and ecosystem service values through mathematical statistics; (2) predicting landscape pattern and ecosystem services change under different scenarios based on cellular automaton model (SLEUTH-3r model); and (3) designing and validating optimized scenario through integrating historical analysis experiments and future multi-comparison suggestions. Results have suggested that landscape composition and configuration can significantly affect regional ecosystem service values, especially the connectivity and shape of landscape. Compact urban growth policy and medium environment protection policy are the appropriate setting for urban expansion plan. Optimization validation of the combined designed scenario implied the reliability of this method. Our results highlighted the significance of integrating application of landscape pattern analysis, ecosystem service value evaluation, model simulation and multi-scenario prediction in urban planning.     

Spatial-temporal analysis of wetland landscape pattern under the influence of artificial dykes in the Yellow River delta

The influence of anthropogenic activities,especially artificial dykes,on the coastal wetland landscape is now considered as a serious problem to the coastal ecosystem.It is important and necessary to analyze changes of coastal landscape pattern under the influence of artificial dykes for the protection and management of coastal wetland.Our study aimed to reveal the quantitative characteristics of the coastal wetland landscape and its spatial-temporal dynamics under the influence of artificial dykes in the Yellow River delta(YRD).It was analyzed by the methods of the statistical analysis of landscape structure,five selected landscape indices and the changes of spatial centroids of three typical wetland types,including reed marshes,tidal fiats and aquaculture-salt fields.The results showed that:(1)Reduction of wetland area,especially the degradation of natural wetlands,had been the principal problem since the dykes were constructed in the YRD.The dykes created conditions for the development of artificial wetlands.However,the new born artificial wetlands were still less than the vanished natural wetlands.(2)Compared with the open area,the building of artificial dykes significantly speeded up the changes of landscape patterns and the aggravation of the landscape fragmentation in the closed area.(3)The changes of area-weighted centroids of three typical wetland landscapes were greatly affected by dykes,and the movement of the centroid of the aquaculture-salt field was very sensitive to the dykes constructed in the corresponding period.     

Study on Development of the West of Shandong Province Based on Overall Regional Development Planning Pattern

The overall regional development planning pattern has been considered to be a new and effective pattern as for development of provincial economy. The article analyzed the current conditions of the west of Shandong Province and tried to find the generation mechanisms of current non-balanced economic development of Shandong Province. And then approaches to regional development were put forward according to the theory of regional development pattern as a whole.     

A Methodology Framework for Regional Land-use Change Studies based on Landsat TM images: A Case Study in Northeast China

Abstract

Land-use change is an important aspect of global environment change. It is, in a sense, the direct result of human activities influencing our physical environment. This paper analyzed the land- use change in Northeast China during 1985–2000 based on Landsat TM images. It divides Northeast China into five land-use zones based on the dynamic degree model of land-use: woodland/grassland-arable land conversion zone, dry land-paddy field conversion zone; urban expansion zone, interlocked zone of farming and pasturing and reclamation and abandon zone. The findings include the obvious increase of cropland area, paddy field and dry land increased by 75 and 276 thousand hm² respectively; urban areas expanded rapidly, areas of town and rural residence increased by 76.8 thousand hm²; areas of forests and grassland decreased sharply with the amounts of 1399 and 1521 thousand hm² respectively; areas of water body and unused land increased by 148 and 514 thousand hm² respectively. This paper also discusses the driving forces in each land-use dynamic zone and finds that some key biophysical factors affect conspicuously the conversion of different land-use types. The relation between land-use conversion and DEM, accumulated temperature (≤10°C) and precipitation was analyzed and represented. The land-use changes In Northeast China resulted from the changing macro social and economic factors and local physical elements. Rapid population growth and management changes can explain the shaping of woodland/grassland-cropland conversion zone. The conversion from dry land to paddy field in the dry land-paddy field conversion zone, apart from the change of physical elements promoting the expansion of paddy field, results from two reasons: one is that the implementation of market economy in China has given farmers the right to decide what and how they plant their crops, the other factor is originated partially from the change of the dietary habit along with the social and economic development. The conversion from paddy field to dry land is caused primarily by the shortfall of irrigation water, which in turn is caused by poor water allocation managed by local governments. The shaping of the reclamation and abandon zone is partially due to the lack of environment protection consciousness among pioneer settlers. The reason for the conversion from grassland to cropland is the relatively higher profits of farming than that of pasturing in the interlocked zone of farming and pasturing. In Northeast China, the rapid expansion of built-up areas results from two factors: the existence of a small number of towns and the huge potential for expansion of the existing towns and cities. The urban land expanded mainly in areas with a gentle topographic relief and low population density.     

The value of urban ecosystem services in New York City: A spatially explicit multicriteria analysis of landscape scale valuation scenarios

Mapping, modeling, and valuing urban ecosystem services are important for integrating the ecosystem services concept in urban planning and decision-making. However, decision-support tools able to consider multiple ecosystem services in the urban setting using complex and heterogeneous data are still in early development. Here, we use New York City (NYC) as a case study to evaluate and analyze how the value of multiple ecosystem services of urban green infrastructure shifts with shifting governance priorities. We first examined the spatial distribution of five ecosystem services – storm water absorption, carbon storage, air pollution removal, local climate regulation, and recreation – to create the first multiple ecosystem services evaluation of all green infrastructure in NYC. Then, combining an urban ecosystem services landscape approach with spatial multicriteria analysis weighting scenarios, we examine the distribution of these ecosystem services in the city. We contrast the current NYC policy preference – which is focused on heavy investment in stormwater absorption – with a valuation approach that also accounts for other ecosystem services. We find substantial differences in the spatial distribution of priority areas for green infrastructure for the valuation scenarios. Among the scenarios we examined for NYC, we find that a scenario in which only stormwater absorption is prioritized leads to the most unevenly distributed ES values. By contrast, we find least variation in ES values where stormwater absorption, local climate regulation, carbon storage, air pollution removal, and recreational potential are all weighted equally.We suggest that green infrastructure planning strategies should include all landscape components that contribute to the production of ecosystem services and consider how planning priority alternatives generate different ecosystem services values.     

中国自然保护区可持续管理模式探讨——伦敦自然保护区管理模式借鉴

近年来，世界各地自然保护区迅速发展，如何有效持续地管理这些自然保护区成为一个重要的问题。文章分析了我国自然保护区现有管理模式的特点与存在的问题，简要介绍了伦敦自然保护区的管理模式现状，根据我国的实际情况，笔者认为中国的自然保护区应采用强制式和完全参与合作式相结合的管理模式，并提出了几点管理模式的改革建议。     

Incorporating Geological Effects in Modeling of Revegetation Strategies for Salt-Affected Landscapes

The work highlights the difficulties of using standard sampling and statistical techniques to investigate regional phenomena and presents an integrated approach combining small-scale sampling with broad-scale observations to provide input into a modeling exercise. It is suggested that such approaches are vital if landscape- and regional-scale processes are to be understood and managed. The way in which the problem is perceived (holistically or piecemeal) affects the way treatments are designed and their effectiveness: past approaches have failed to integrate the various scales and processes involved. Effective solutions require an integrated holistic response.