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1.
以江苏省高风险农产品产地安全信息管理为例,针对农产品产地安全信息的数据特征以及管理决策需要,提出了一种基于WebGIS技术的农产品产地安全信息管理系统设计方案,对系统的设计目标、主要任务、系统结构、数据库结构和主要功能进行探讨.根据系统的主要任务设计了地图浏览、数据查询、数据统计、产地监测信息管理和产地适宜性信息管理5类功能;系统采用客户层、中间业务处理层和服务器数据层3层体系结构;系统数据库设计为索引表、属性表和数据表3层结构;采用C#程序语言和MapXtreme开发平台对系统进行了初步开发与实施.  相似文献   

2.
最近几年,位于马西南部的里奥格兰德联合大学的研究生土木工程项目开展了一些与建筑环境的可持续性有关的活动.其中一些活动与教育有关,一些活动与设计和建造有关.本文介绍了应用可持续性原则的项目的总体概念框架及其主要总体目标.新近的一个项目(对一所技术学校的提议)说明了如休在一个具体的项目处理框架及其目标问题1.文章也简要介绍了其他研究和设计活动.并简单讨论了把可持续性问题纳入发发中国家的土地利用规划以及项目设计的障碍.  相似文献   

3.
最近几年,位于马西南部的里奥格兰德联合大学的研究生土木工程项目开展了一些与建筑环境的可持续性有关的活动.其中一些活动与教育有关,一些活动与设计和建造有关.本文介绍了应用可持续性原则的项目的总体概念框架及其主要总体目标.新近的一个项目(对一所技术学校的提议)说明了如休在一个具体的项目处理框架及其目标问题1.文章也简要介绍了其他研究和设计活动.并简单讨论了把可持续性问题纳入发发中国家的土地利用规划以及项目设计的障碍.  相似文献   

4.
信息     
《环境化学》编辑部网站于2006年1月1日开通为了适应科技期刊网络化、数字化的要求,本刊初步建立在线投稿、查询系统,并开通《环境化学》编辑部网站(http://hjhx.rcees.ac.cn).该采编系统的使用和网站的开通,既方便作者在线投稿、及时查询稿件审理情况,又可以缩短稿件处理周期,  相似文献   

5.
辽宁东部山区几种主要森林植被类型土壤渗透性能研究   总被引:6,自引:0,他引:6  
沿辽河水系设置临时标准地 ,对辽宁东部山区具有代表性的油松林、落叶松林、红松林、柞木林、杂木林及灌丛 6种植被类型的土壤水分的入渗性能进行了研究。结果表明 ,辽东山区 6种植被类型下土壤都表现出较强的渗透性能。A层的初始入渗率 (f0 /mm·min- 1) 1 2 .8~ 6 1 .1 ,平均值为 38.7,B层 1 6 .8~4 1 .7,平均值为 2 7.0 ,C层 2 9.2~ 38.2 ,平均值为 2 4 .4 ;A层的稳定入渗率 (fc/mm·min- 1) 2 .6~ 4 .2 ,平均值为 3.5 ,B层 2 .2~ 4 .1 ,平均值为 2 .9,C层 1 .1~ 3.3,平均值为 2 .2 ;A层的饱和导水率 (k10 /mm·min- 1)1 .5 3~ 2 .2 3,平均值为 1 .86 ,B层 0 .77~ 2 .0 5 ,平均值为 1 .2 7,C层 0 .5 0~ 1 .2 8,平均值为 0 .79。不同植被类型下不同土壤发生层次的入渗能力差异显著 :一般地 ,阔叶林下土壤的入渗性能明显好于针叶林 ,榛丛下土壤也表现出很好的渗透性能 ;不同土层入渗性能大小为A层 >B层 >C层。林龄差异在 2个龄级以上时 ,林龄越大 ,土壤初渗性能越好。用Horton方程拟合土壤饱和渗透过程 ,模拟结果与实测结果相近。  相似文献   

6.
体系框架设计是生态环境标准体系建设的基础。按照标准体系设计的基本原则,结合我国生态环境管理工作实践,提出了由生态环境管理领域和技术内容类别二维构成的生态环境标准体系框架。体系框架中,领域维包括保护地管理、生物多样性保护、水土保持、沙化与石漠化控制、开发建设工程生态环境保护、外来物种环境风险管理、转基因生物环境安全、农村生态环境保护、城市生态环境保护、森林生态保护、草原生态保护、荒漠生态保护、湿地生态保护、内陆水域生态保护、海洋生态保护、流域(区域)生态保护和综合17个大类,技术维包括术语、分类与信息、区划、质量、保护与恢复、监测检测、评价和综合8个大类,并就每个大类的相关内容和标准作了详细说明。  相似文献   

7.
最近几年,位于巴西南部的里奥格兰德联合大学的研究生土木工程项目开展了一些与建筑环境的可持续性有关的活动.其中一些活动与教育有关,一些活动与设计和建造有关,本文介绍了应用可持续性原则的项目的总体概念框架及其主要总体目标,新近的一个项目(对一所技术学校的提议)说明了如何在一个具体的项目中处理框架及其目标问题.文章也简要介绍了其他研究和设计活动,并简单讨论了把可持续性问题纳入发展中国家的土地利用规划以及项目设计的障碍.  相似文献   

8.
基于γ-环糊精的金属有机框架(γ-CD-MOF)在气体储存与分离、药物传递、环境净化及传感等方面都有广阔的应用前景.然而,γ-CD-MOF的水稳定性差阻碍了这种多孔材料的实际应用.因此,增加γ-CD-MOF在潮湿环境的稳定性是其在实际应用中的巨大挑战.利用司盘85极性的羟基端与γ-CD-MOF金属离子的物理吸附作用,通过简单的溶液浸泡工艺在γ-CD-MOF的外表面修饰一层司盘85得到水稳定的γ-CD-MOF.结果显示:在92%相对湿度下暴露25 d后,司盘85修饰的γ-CD-MOF仍然保持完整的晶体结构和形态,而γ-CD-MOF在相同湿度下暴露1 d后,其晶体结构已经完全被破坏并失去其固有的多孔性.此外,γ-CD-MOF-SP85能够有效吸附污染气体CO2及甲醛.本研究表明疏水的司盘85保护层能够有效阻止水分子进入γ-CD-MOF框架内,从而提高γ-CD-MOF的耐湿性.这种简单易行的一步法将为制备水稳定的金属有机框架(MOF)开辟一条新的途径.(图8参22)  相似文献   

9.
多介质土壤层系统(MSL)是一种适合于农村地区处理生活污水的新型分散式污水处理系统。试验设计了4个长、宽、高分别为50、10、60 cm的MSL系统,该系统由土壤混合层和通水层交叠成层组成。土壤混合层选用普通砂土,添加木屑混合木炭/秸秆、铁粒/膨润土按照7∶2∶1的干质量比例均匀混合,通水层选用沸石或者普通砾石。MSL系统在水力负荷500 L.m-2.d-1下连续运行2个月。结果表明,4个MSL系统对CODCr的平均去除率差别不大,为79.58%~80.22%;对TP去除率为47.83%~82.60%,添加沸石和膨润土可以较大程度地增加TP去除率;对TN的去除率为29.74%~57.89%,通水层为沸石的MSL系统去除率明显优于砾石;木炭混合木屑较秸秆更适合作为MSL系统的有机碳源。  相似文献   

10.
利用TAIL-PCR和RT-PCR技术克隆云芝植酸酶基因   总被引:3,自引:0,他引:3  
从采绒革盖菌(Coriolus versicolor,常被称为杂色云芝)中筛选到产植酸酶基因.根据植酸酶基因的保守序列设计引物P1、P2,从云芝中分离克隆植酸酶基因的片段.再在分离到的已知序列的5′端和3′端设计嵌套的特异引物SP1、SP2、SP3和SP1′、SP2′、SP3′,利用TAIL-PCR技术进行分离已知序列的侧翼序列.结合Blastn、ORF和Primer5.0软件,在侧翼序列上设计特异引物P3、P4,最终从云芝中分离克隆到全长的植酸酶基因B4.再在B4序列的基础上设计引物phyP rt1、phyP rt2,利用这两个引物通过RT-PCR技术从云芝中克隆到全长的植酸酶基因B5.通过分析,分离克隆到的植酸酶基因可能是新的基因.图4参12  相似文献   

11.
Abstract:  Designing policies that harness the motivations of landowners is essential for conserving threatened habitats on private lands. Our goal was to understand how to apply ethnographic information about family-forest owners to the design of conservation policy for Oregon white oak (Quercus garryana) in the Willamette Valley, Oregon (U.S.A.). We examined owners' knowledge, beliefs, values, and socioeconomic contexts through in-depth individual and focus-group interviews to understand their motivations to conserve oak. We then used Schneider and Ingram's (1990) policy analysis framework to compare owners' motivations to the logic of policy. Owners had complex motivations for conserving oak. Despite this complexity, all 5 categories of policy that Schneider and Ingram describe hold promise. Policies that use symbolism to inspire behavior and policies that build capacity can harness owners' stewardship ethics and moral obligations. Policies that offer tangible rewards can build on owners' utilitarian motives. Policies that permit and prohibit behavior can tap owners' concerns about rule violations. Policies that promote voluntary, collaborative efforts can accommodate owners' need for autonomy and flexibility.  相似文献   

12.
In line with sustainable development principles, the reactions to modern architecture and planning have led to a new appreciation of traditional cities and urban environments.

Considering the extensive neglect and devastation of local values in our cities and towns, urban development practice in Turkey cannot be said to meet the requirements of sustainability. This paper, therefore, will explore the logic of sustainable development and focus on the components of good urban design which are needed to produce it. Since promoting sustainable lifestyles in our towns and cities depends mainly on the design of the physical environment, the paper will propose a set of key design principles that can deliver sustainable urban development through exploring the qualities of ‘traditional urbanism’ in the Turkish cities as well as examining the latest approaches to urban design.  相似文献   

13.
Changing land use in the tropics has resulted in vast areas of damaged and degraded lands where biodiversity has been reduced. The majority of research on biodiversity has been focused on population and community dynamics and has rarely considered the ecosystem processes that are intimately related. We present a framework for examining the effects of changes in biodiversity on ecosystem function in natural, managed, and damaged tropical forests. Using a whole-ecosystem approach, the framework identifies key nutrient and energy cycling processes and critical junctures or pathways, termed interfaces, where resources are concentrated and transferred between the biotic and abiotic components of the ecosystem. Processes occurring at these interfaces, and the organisms or attributes participating in these processes, exert a strong influence on ecosystem structure. We use examples from Puerto Rico, Southern China, Dominica, and Nicaragua to illustrate how the functional diversity framework can be applied to critically examine the effects of changes in biodiversity on ecosystem function, and the relative success or failure of rehabilitation strategies. The few available data suggest that functional diversity, and not just species richness, is important in maintaining the integrity of nutrient and energy fluxes. High species richness, however, may increase ecosystem resiliency following disturbance by increasing the number of alternative pathways for the flow of resources. We suggest ways in which the framework of functional diversity can be used to design research to examine the effects of changes in biodiversity on ecosystem processes and in the design and evaluation of ecosystem management and land rehabilitation projects in the tropics.  相似文献   

14.
ABSTRACT

Due to the special geographic locations and multiple typhoons a year, the frequent strong winds bring great discomfort and danger to the daily lives of the urban residents in southeast coast of China. The strategic design of landsenses pattern on different scales can help reduce gale days in urban areas while delivering diverse additional benefits such as pollution control and biodiversity habitat protection. Although the greatest gale days are observed in cold and damp winters, there is comparatively little information available for land managers to determine an appropriate strategy for landsenses pattern design under these climatic conditions. We present a framework for prioritization and selection of landsenses pattern for gale day reductions. The framework is supported by examining the relationships between urban landsenses pattern evolution and gale day mitigation in the past, with which we used to develop implementation guidelines that maximize reductions of urban surface gale days. We focus particularly on quantifying the benefits of four types of landsenses: land-use patterns, urban road network, architectural patterns, and vertical greening systems (green walls and facades) and demonstrate how to apply the framework with a case study from Pingtan Island, China.  相似文献   

15.
Despite an abundance of research reaffirming biodiversity's importance to the health of the planet and society, species continue to go extinct at an alarming rate. Why has continued research on the value of biodiversity not had the intended effect and what can be done about it? We considered biodiversity loss as a public value failure and the result of a misalignment between the logic of inquiry (which guides scientists) and the logic of action (which guides practitioners). We drew lessons from our own research to propose the creation of a national biodiversity strategy designed to link the logic of inquiry with the logic of action and coordinate the production of actionable conservation science and informed conservation action.  相似文献   

16.
Wildlife managers face the daunting task of managing wildlife in light of uncertainty about the nature and extent of future climate change and variability and its potential adverse impacts on wildlife. A conceptual framework is developed for managing wildlife under such uncertainty. The framework uses fuzzy logic to test hypotheses about the extent of the wildlife impacts of past climate change and variability, and fuzzy multiple attribute evaluation to determine best compensatory management actions for adaptively managing the potential adverse impacts of future climate change and variability on wildlife. A compensatory management action is one that can offset some of the potential adverse impacts of climate change and variability on wildlife. Implementation of the proposed framework requires wildlife managers to: (1) select climate impact states, hypotheses about climate impact states, possible management actions for alleviating adverse wildlife impacts of climate change and variability, and future climate change scenarios; (2) choose biological attributes or indicators of species integrity; (3) adjust those attributes for changes in non-climatic variables; (4) define linguistic variables and associated triangular fuzzy numbers for rating both the acceptability of biological conditions under alternative management actions and the relative importance of biological attributes; (5) select minimum or maximum acceptable levels of the attributes and reliability levels for chance constraints on the biological attributes; and (6) define fuzzy sets on the extent of species integrity and biological conditions and select a fuzzy relation between species integrity and biological conditions. A constructed example is used to illustrate a hypothetical application of the framework by a wildlife management team. An overall best compensatory management action across all climate change scenarios is determined using the minimax regret criterion, which is appropriate when the management team cannot assign or is unwilling to assign probabilities to the future climate change scenarios. Application of the framework can be simplified and expedited by incorporating it in a web-based, interactive, decision support tool.  相似文献   

17.
The trans-regional characteristics of watershed governance produce more problems beyond the capacity of each individual water-related department, leading to the fragmentation of watershed management. The River Chief System (RCS) has experienced swift developments over the past decade in China by appointing the local government heads as river chiefs. RCS works efficiently in the short-term due to its superiority in the inclusion of clear responsibility, authority, and multi-sectoral collaboration. However, the characteristics of the authority-based vertical coordination of the hierarchical system remain unchanged, and therefore the problems of organizational logic and the responsibility dilemma still exist. Tasks including perfecting of laws, integrated watershed management, and public participation still need to be completed. RCS reflects the routine and characteristics of the migration of national governance, and as such provides new insights for other developing countries in the design of river management systems.  相似文献   

18.
Wildlife health assessments help identify populations at risk of starvation, disease, and decline from anthropogenic impacts on natural habitats. We conducted an overview of available health assessment studies in noncaptive vertebrates and devised a framework to strategically integrate health assessments in population monitoring. Using a systematic approach, we performed a thorough assessment of studies examining multiple health parameters of noncaptive vertebrate species from 1982 to 2020 (n = 261 studies). We quantified trends in study design and diagnostic methods across taxa with generalized linear models, bibliometric analyses, and visual representations of study location versus biodiversity hotspots. Only 35% of studies involved international or cross-border collaboration. Countries with both high and threatened biodiversity were greatly underrepresented. Species that were not listed as threatened on the International Union for Conservation of Nature Red List represented 49% of assessed species, a trend likely associated with the regional focus of most studies. We strongly suggest following wildlife health assessment protocols when planning a study and using statistically adequate sample sizes for studies establishing reference ranges. Across all taxa blood analysis (89%), body composition assessments (81%), physical examination (72%), and fecal analyses (24% of studies) were the most common methods. A conceptual framework to improve design and standardize wildlife health assessments includes guidelines on the experimental design, data acquisition and analysis, and species conservation planning and management implications. Integrating a physiological and ecological understanding of species resilience toward threatening processes will enable informed decision making regarding the conservation of threatened species.  相似文献   

19.
Individuals who are likely to realize the largest benefits from improvements in air quality often depend on other members of their households to make time or monetary contributions to their care. The presence of these dependency relationships among household members poses challenges for benefit estimation since it is unlikely that the conditions necessary for recovering the underlying individual preferences from household choices are satisfied in this setting. We propose a conceptual framework that highlights the role of these dependencies in the choice models used to estimate the willingness to pay for environmental quality improvements. We design a complementary stated preference survey that describes hypothetical dependency relationships for household members of different ages to test the implications of our conceptual model. Respondents' stated choices take into account the proposed care-giving responsibilities for young children and teenagers but not for older adults.  相似文献   

20.
Connectivity for conservation: a framework to classify network measures   总被引:3,自引:0,他引:3  
Rayfield B  Fortin MJ  Fall A 《Ecology》2011,92(4):847-858
Graph theory, network theory, and circuit theory are increasingly being used to quantify multiple aspects of habitat connectivity and protected areas. There has been an explosive proliferation of network (connectivity) measures, resulting in over 60 measures for ecologists to now choose from. Conceptual clarification on the ecological meaning of these network measures and their interrelationships is overdue. We present a framework that categorizes network measures based on the connectivity property that they quantify (i.e., route-specific flux, route redundancy, route vulnerability, and connected habitat area) and the structural level of the habitat network to which they apply. The framework reveals a lack of network measures in the categories of "route-specific flux among neighboring habitat patches" and "route redundancy at the level of network components." We propose that network motif and path redundancy measures can be developed to fill the gaps in these categories. The value of this framework lies in its ability to inform the selection and application of network measures. Ultimately, it will allow a better comparison among graph, network, and circuit analyses, which will improve the design and management of connected landscapes.  相似文献   

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