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531.
建立网络生态水库系统实现城市河流的可持续发展   总被引:2,自引:0,他引:2  
姜跃良  罗麟 《四川环境》2003,22(3):33-34,41
城市河流在城市及周边地区经济发展和生态保护中地位十分重要。网络生态水库系统可以克服我国水资源时空分配不均的弊端,优化水资源配置,满足各城市生产生活需要,实现可持续发展。  相似文献   
532.
Visual Basic在数字林业系统中二次开发地理信息系统   总被引:3,自引:0,他引:3  
在当今信息时代,林业安全管理要实现数字林业系统必须由3S技术作为支持。本文主要介绍用VisualBasic二次开发地理信息系统(GIS)管理软件ArcInfo,实现林业各地理要素的显示漫游和查询等功能。  相似文献   
533.
本文从体制、机构、人员、资源等方面阐述了林业安全生产的现状,并提出了相应的管理对策。  相似文献   
534.
从城镇发展度、城镇宜居度、城乡协调度和城镇发展效率4个维度综合评估了2005—2019年关中平原城市群城镇化质量。结果表明:①关中平原城市群城镇化质量呈快速上升趋势,但整体质量依然处于较低水平。②城镇发展系统和城镇宜居系统是关中平原城市群城镇化质量提升的重要维度,城镇发展效率和城乡协调度是城镇化质量提升的短板,经济城镇化和社会城镇化质量快速发展是城镇化质量提升的重要动力,城乡协调度是城镇化质量提升的关键维度。③研究后期关中平原城市群各城市城镇化质量差异明显缩小,城市之间的关联性增强,核心城市辐射带动作用日益凸显。  相似文献   
535.
基于国家粮食安全的长江三角洲地区耕地保护探讨   总被引:4,自引:0,他引:4  
从经济增长规律与发展阶段来看,作为中国经济发展的核心区域之一,长江三角洲地区耕地的减少趋势还将持续一定时期。分析了长江三角洲地区粮食及耕地现状,通过相关性分析得到耕地预测模型,并预测了未来耕地变化态势,揭示出耕地损失率高峰值将在“十一五”期间出现。通过国家粮食安全的态势判断以及长江三角洲地区耕地减少与国家粮食安全之间的关系分析,得出长江三角洲地区耕地面积的减少所导致的粮食减产对国家粮食安全的影响较小,而国家粮食安全水平的变化会影响长江三角洲地区的粮食有效供给的结论。从而提出耕地保护的思路:“十一五”期间,长江三角洲地区应采取积极的保护政策;进入“十二五”之后,耕地保护政策应转为严格控制。为此,还提出了重在保护质量、保护其生态景观功能、加大后备资源开发、减少非农占用、加强政策管理等对策建议。  相似文献   
536.
济南市环境、社会、经济协调发展评价   总被引:4,自引:0,他引:4  
建立了济南市城市环境、社会、经济协调评价指标体系,采用多目标二级决策方法对各指标的权重进行分配;在已有协调度计算方法的基础上,构建了协调度的计算公式;并运用该指标体系和协调度公式对济南市环境、社会经济协调状况进行评判。结果表明济南市的环境、社会经济之间发展是不平衡的,协调状况为中级协调水平;环境综合指数较低,表明环境的建设滞后于社会经济的发展。  相似文献   
537.
Non-structural streambank stabilization, or bioengineering, is a common stream restoration practice used to slow streambank erosion, but its ecological effects have rarely been assessed. We surveyed bank habitat and sampled bank macroinvertebrates at four bioengineered sites, an unrestored site, and a comparatively less-impacted reference site in the urban Peachtree-Nancy Creek catchment in Atlanta, GA, USA. The amount of organic bank habitat (wood and roots) was much higher at the reference site and three of the bioengineered sites than at the unrestored site or the other bioengineered site, where a very different bioengineering technique was used (“joint planting”). At all sites, we saw a high abundance of pollution-tolerant taxa, especially chironomids and oligochaetes, and a low richness and diversity of the bank macroinvertebrate community. Total biomass, insect biomass, and non-chironomid insect biomass were highest at the reference site and two of the bioengineered sites (p < 0.05). Higher biomass and abundance were found on organic habitats (wood and roots) versus inorganic habitats (mud, sand, and rock) across all sites. Percent organic bank habitat at each site proved to be strongly positively correlated with many factors, including taxon richness, total biomass, and shredder biomass. These results suggest that bioengineered bank stabilization can have positive effects on bank habitat and macroinvertebrate communities in urban streams, but it cannot completely mitigate the impacts of urbanization.  相似文献   
538.
Fast economic and social changes in recent years in China have brought massive expansion, redevelopment, and restructuring of cities. These changes offer cities the opportunity to improve environmental quality through urban green spaces (UGSs) and to address the challenges of meeting community aspirations. This study explored peoples’ minds concerning UGSs in Guangzhou city in south China in relation to the following: (1) knowledge and perception of 25 ecosystem services and 8 negative impacts; (2) attitude toward site condition and management; (3) expectation of landscape design; and (4) preference ranking of venues. A questionnaire was designed to solicit opinions from 340 respondents randomly chosen from residents living in the study area. The results indicated widespread recognition of ecosystem services and strong support of UGS programs. Negative responses were weakly expressed. Amelioration of urban microclimate and environmental quality were emphasized. Environmental functions stressed in publicity programs, together with aggravating environmental problems in the city, tended to focus respondents’ attention on UGS benefits. Wildlife habitat, species conservation and other natural ecosystem services drew limited concerns. Awareness of economic benefits was very low. Visual-landscape contributions with strong preference for naturalistic design and recreational benefits were highlighted. Compared with other countries, Guangzhou residents were characterized by visual–scenic–recreation orientation and pragmatic–utilitarian perception of UGSs, reflecting underlying differences in the understanding of inherent ecosystem services of green spaces. Relevant UGS policies and practices could adopt the approaches of market survey, citizen participation, and precision planning in order to meet increasingly mature and refined demands. Citizens’ understanding of high-order ecosystem services could be enhanced to encourage appreciation of nature and their associated benefits.  相似文献   
539.
Participatory environmental management can empower communities and enhance the sustainability of environmental interventions. However, existing power structures and inequalities along class, gender, or ethnic lines could prevent part of the community from accessing the full benefits of the intervention. An analysis of determinants of the willingness-to-participate in an environmental intervention in a Beirut neighborhood is conducted. Socioeconomic, health-risk distribution, and perception of community efficacy are used as predictors. A randomly selected sample of residents was surveyed. Respondents were asked to specify the frequency with which they were willing to be involved in an intervention to address priority environmental problems in the neighborhood. Bivariate and multivariate ordinal regression analyses were conducted. Tests of significance were based on the 95% confidence intervals (CI) of the odds ratio (OR). Males versus females (OR = 4.89, P < 0.001), respiratory patients versus nonsufferers (OR = 5.65, P < 0.001), tenants versus house owners (OR = 2.98, P < 0.01), and the less educated versus the more educated (OR = 2.42, P < 0.05) were significantly more likely to be willing to participate. The reluctance of female community members to participate might be a major hindrance to community-based environmental protection and special strategies must be devised to overcome it. On the other hand, respondents suffering from an illness perceived to be related to environmental toxins are likely to be strong participants in environmental conservation efforts. Finally, the study yielded no evidence that belief or lack of it in the efficacy of community action is a good predictor of the willingness-to-participate in such action.  相似文献   
540.
随着城市的发展,轨道交通在各大城市中得到迅速发展,但与之相伴的环境振动问题也日益突显.为研究城市轨道交通地下线列车运行速度、线路条件、减振措施等运营条件对环境振动影响,在某地铁线路隧道内进行了环境振动源强测试.结果表明,隧道壁源强位置处Z振级随着速度的增加而增大,列车通过速度在57~75 km/h变化时,列车速度每增加...  相似文献   
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