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161.
协调性分析是规划环境影响评价的重要组成部分,它的分析对象是被评价的规划草案及其相关的政策、法规、规划等。在以规划草案为评估对象的环境影响评价中,协调性分析能够起到两种作用:解释制定规划草案的“政策背景环境”,和检查规划草案是否存在资源保护、环境保护方面的缺陷和不足。这两种作用不能被截然分开。协调性分析的目的是帮助环评单位和公众更好地理解规划制定的背景,以及使规划环评针对草案的缺陷与不足提出相应的环境目标和环境保护对策。分析结果一般可以使用矩阵来表示。如果规划环评可以早期介入到规划的制定中,描述“政策背景环境”和制定可选择性方案这两个程序就可以达到协调性分析的目的.因此不再需要进行专门的协调性分析。 相似文献
162.
Xin Dong Siyu Zeng Jining Chen Dongquan Zhao 《Frontiers of Environmental Science & Engineering in China》2008,2(2):150-156
In recent years, the urban drainage system in China is facing the dual pressure of renovation and construction. This requires
that the integrated assessment for the planning and operation of the urban drainage system is obligatory. To evaluate the
urban drainage system, an integrated assessment methodology based on the analytic hierarchy process (AHP), integrated simulation,
and fuzzy assessment is established. This method is a multi-criteria decision adding app roach to the assessment of the urban
drainage system comprehensively. Through the integration of the Storm Water Management Model (SWMM), a simple wastewater treatment
plant model, and a surface water quality model, an integrated modelling system for the urban drainage system is developed
and applied as a key tool for assessment. Using the established method, a case study in Shenzhen City has been implemented
to evaluate and compare two urban drainage system reno vation plans, the distributed plan and the centralized plan. Because
of the particularity of this case study, the established method is not applied entirely. Considering the water environ mental
impact, ecological impact, technological feasibility, and economic cost, the integrated performance of the distri buted plan
is better. As shown in this case study, the proposed method is found to be both effective and practical. 相似文献
163.
随着市场机制的不断完善,城市土地利用的不确定性需要在战略定位上具备更大的弹性以适应市场的发展。基于弹性理念,在对城市用地开发条件进行辨识的基础上,对土地开发的需求进行了弹性预测,依据人口极限计算出土地弹性需求值域的上下限,确定弹性范围,提出适应社会经济发展需要的用地开发战略目标,并找到将其变为现实的正确途径。在结构上从城市用地开发战略目标的确定、城市用地发展方向的定位以及城市用地模式的选择3个方面,对城市用地开发的战略研究做了深入分析。同时,引入新的思想和方法以及多学科多视角,定性与定量相结合来制定城市用地开发的战略目标。最后,利用上海市宝山区作为实例,对基于弹性理念的城市用地开发战略的研究做了实证分析。 相似文献
164.
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. 相似文献
165.
Using historical General Land Office record as a reference, this study employed a landscape-scale disturbance and succession model to estimate the future cumulative effects of six alternative management plans on the tree species composition for various physiographic settings for the Mark Twain National Forest in Missouri. The results indicate that over a 200-year horizon, the relative abundance of black oak and pine species groups will decrease and the relative abundance of the white oak species group will increase, regardless of management strategy. General Land Office witness tree records provide a measure of tree species composition in the period from 1800 to 1850, prior to the large-scale influx of European settlers. Compared to the tree species composition described in the General Land Office records, the six contemporary management alternatives considered all would lead to a lower abundance of pine species, a higher abundance of red/black oak species, and a slightly higher abundance of white oak species after 200 years. Impacts of management on tree species composition varied with physiographic settings. The projected relative abundance of pine differed significantly across the five physiographic classes over the first 40 years of the simulation. In the medium term (simulation years 41-100) the projected relative pine abundance differed significantly among only four physiographic classes. In the long term (simulation years 100-200) the projected relative pine abundance differed for only one physiographic class. In contrast, differences among physiographic classes in the relative abundance of black oaks and white oaks increased over time. In general, the expected long-term differences in relative tree species abundance among six proposed alternative management plans are small compared to shifts in tree species composition that have occurred from 1850 to the present. 相似文献
166.
云南高原湖泊流域土地利用与水质变化异质性分析 总被引:1,自引:0,他引:1
以云南省九大高原湖泊为例,通过面板数据方式分析对高原湖泊流域土地利用类型变化,通过库兹涅兹曲线相关内容对利用强度的分析以及与水质的动态变化情况,得到耕地、园地、湿地面积与湖泊含磷量存在一定负相关.林地、牧草地、建设用地面积与湖泊含磷量存在一定正相关.牧草地、耕地、园地、湿地面积与湖泊含氮量存在一定负相关,建设用地面积与湖泊含氮量存在一定正相关.园地和耕地面积与污染综合指数存在负相关,建设用地面积与污染综合指数存在负相关.分析指出,滇池、泸沽湖处于流域协调区间,阳宗海、抚仙湖、星云湖、程海处于流域冲突区间,洱海、异龙湖处于冲突区间向协调区间转型过程中. 相似文献
167.
刘东武 《中国环境管理干部学院学报》2011,21(3):26-29
通过对廊坊市环境容量现状和土地利用与生态环境关系的分析,提出了廊坊市生态适宜的土地利用目标和调控指标,从而构建环境友好型土地利用模式。 相似文献
168.
基于网络的交通安全宣传教育研究 总被引:1,自引:0,他引:1
为了建立我国交通安全宣传教育网络平台,通过网络平台进行多形式的交通安全宣传教育。采用网站检索的方法,梳理了国内、外主要城市交通安全宣传教育网站,并从专业性、系统性、针对性、形式多样性等角度进行研究。研究发现国外交通安全网站具有分类细致、系统性强、参与互动性强等特点。因此建议我国应加快明确重点教育人群,建立系统性的、专业的、多形式的交通安全宣教内容,引入社会团体等加入宣传教育的队伍,提高全面积极参与、提高关注度。 相似文献
169.
《大气污染防治行动计划》实施的环境健康效果评估 总被引:9,自引:7,他引:2
为了定量评估《大气十条》实施带来的环境健康效益,本文首先依据PM_(2.5)浓度和人口数据,分析2013~2017年全国人口加权浓度的变化,其次利用Ben MAP模型对全国338个地级及以上城市2013年PM_(2.5)基准情景和2017年PM_(2.5)控制情景进行分析,定量分析全国31个省(市)及338个地级及以上城市减少过早死亡人数.结果表明,由于PM_(2.5)浓度大幅下降,2013~2017年全国PM_(2.5)人口加权浓度呈逐年下降趋势;北京、天津、河北等京津冀及周边地区减少过早死亡人数最多. 2017年全国280个城市避免过早死亡人数有所增加,58个城市避免过早死亡人数有所下降.以WHO过渡期第1阶段目标值(PM_(2.5)年均浓度为35μg·m-3)作为控制情景,估算2013年全国过早死亡人数约为101 293人,2017年约为41 080人,《大气十条》的实施大约避免60 213人过早死亡.依据支付意愿法调查结果,估算增加的健康效益约为549. 7亿元. 相似文献
170.
基于“三生”适宜性的县域土地利用冲突识别与分析 总被引:1,自引:0,他引:1
精准识别潜在土地利用冲突有利于预警权衡和协调冲突用地,有利于科学进行国土空间规划。以“三调”修正数据为基础,基于生产、生活、生态视角,构建高植被覆盖率县域生产、生活、生态即“三生”适宜性评价模型与土地利用冲突识别矩阵,并选取横峰县进行实证分析。结果表明:(1)横峰县“三生”适宜性用地的空间分布与面积构成差异显著,且存在明显的空间叠加特征,暗示着研究区土地利用存在冲突;(2)从潜在冲突识别的结果来看,土地利用适宜区、冲突激烈区、冲突中度区、冲突一般区及冲突微弱区面积占比分别为64.02%、9.66%、17.19%、1.66%、7.48%;(3)各个冲突类型区空间分布、表现形式的差异性决定了冲突和解的对策也需因地制宜。研究结果可为相关及类似县域的国土空间规划提供理论参考。 相似文献