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941.
四川金堂县生态旅游气候资源评价   总被引:3,自引:0,他引:3  
对四川省金堂县生态旅游资源的统计分析和评价表明,该地区属第一类生态旅游圈,生态旅游资源极富异趣.利用近10年气象资料逐日计算人体舒适度,平均每年舒适天数182d,为一类地区;适宜旅游的时段是3月下旬~6月下旬和9月上旬~11月中旬.  相似文献   
942.
根据成都市1991~2000年基地蔬菜历年上市量与同期气象资料进行统计分析表明,如人均日占有量250g,全年供应均衡;如人均日供应量400g,则全年缺菜13.3万t,其中3~4月、9~10月为淡季,且上市期主要集中在5~9月.本研究为成都市蔬菜品种、产业结构调整决策提供依据.  相似文献   
943.
ABSTRACT: The term flashiness reflects the frequency and rapidity of short term changes in streamflow, especially during runoff events. Flashiness is an important component of a stream's hydrologic regime. A variety of land use and land management changes may lead to increased or decreased flashiness, often to the detriment of aquatic life. This paper presents a newly developed flashiness index, which is based on mean daily flows. The index is calculated by dividing the pathlength of flow oscillations for a time interval (i.e., the sum of the absolute values of day‐to‐day changes in mean daily flow) by total discharge during that time interval. This index has low interannual variability, relative to most flow regime indicators, and thus greater power to detect trends. Index values were calculated for 515 Midwestern streams for the 27‐year period from 1975 through 2001. Statistically significant increases were present in 22 percent of the streams, primarily in the eastern portion of the study area, while decreases were present in 9 percent, primarily in the western portion. Index values tend to decrease with increasing watershed area and with increasing unit area ground water inputs. Area compensated index values often shift at ecoregion boundaries. Potential index applications include evaluation of programs to restore more natural flow regimes.  相似文献   
944.
ABSTRACT: Successful stream rehabilitation requires a shift from narrow analysis and management to integrated understanding of the links between human actions and changing river health. At study sites in the Puget Sound lowlands of western Washington State, landscape, hydrological, and biological conditions were evaluated for streams flowing through watersheds with varying levels of urban development. At all spatial scales, stream biological condition measured by the benthic index of biological integrity (B‐IBI) declined as impervious area increased. Impervious area alone, however, is a flawed surrogate of river health. Hydrologic metrics that reflect chronic altered streamflows, for example, provide a direct mechanistic link between the changes associated with urban development and declines in stream biological condition. These measures provide a more sensitive understanding of stream basin response to urban development than do treatment of each increment of impervious area equally. Land use in residential backyards adjacent to streams also heavily influences stream condition. Successful stream rehabilitation thus requires coordinated diagnosis of the causes of degradation and integrative management to treat the range of ecological stressors within each urban area, and it depends on remedies appropriate at scales from backyards to regional storm water systems.  相似文献   
945.
旅游专项规划环境影响评价探讨   总被引:13,自引:0,他引:13  
旅游专项规划环境影响评价是我国新颁布的环境影响评价法所规定的一种新的环境影响评价形式。应以生态旅游理论为指导,突出反映规划环境影响评价的特点,引入区域环境影响评价的方法学开展旅游专项规划环境影响评价工作。文中对旅游专项规划环境影响评价的要点及指标体系进行了系统探讨。  相似文献   
946.
2 (1 and 24 h), SO2 (1 and 24 h), O3 (1 h) and PM10 (24 h). The AQI is linked to the new air quality guidelines in Finland. The AQI is based on acute health effects, but long-term effects on nature and materials are also taken into consideration. Subindices are calculated hourly for all pollutants and for a given hour the highest subindex becomes the AQI. AQI values are currently calculated for the center of Helsinki and for typical suburban areas.  相似文献   
947.
本文提出了农业生产潜力指数评价的基本理论和方法,并利用这一评价方法对内江市主要家业作物的生产潜力的进行了评价分析。  相似文献   
948.
从试验考核指标出发,运用“水质指数(WQI)”,分析影响废水处理效果的诸因素,选取pH值和处理剂加入量为可控因素,利用优选法找出钻井废水处理的最佳条件;选取两个因素水平进行正交试验,选用L4(23)正交表,合理安排试验,确定最优因素水平组合。总之,应用优选法及正文试验于钻井废水处理工作中,获得了处理的最佳条件,对钻井生产中废水处理统一操作,降低消耗,保证废水处理达标率起着很重要的作用。  相似文献   
949.
用蚕豆初生根尖细胞微核技术监测污染的水系统,1986年已被国家环保局编入《环境监测技术规范》(水环境部分),并已在全国推广使用。现在利用这一测试方法对大庆南线排水干渠进行监测,从对生物的毒性角度出发,评价油田30年开发以来水体的污染程度,为环境管理和防治提供了新的科学依据。  相似文献   
950.
A Profile and Management of the US Army's underground storage tanks   总被引:1,自引:0,他引:1  
The US Army owns more than 10,000 underground storage tanks (USTs), many of which are old and may be leaking. The Resource Conservation and Recovery Act of 1976 required tank owners to collect and report data on them by May 1986. In order to manage the large amounts of information on its USTs, the Army developed a microcomputer-based data base system. The data base system is user friendly and allows the user to store, organize, and manipulate the UST data. A leak potential index (LPI) was also developed and calculated for each of the Army's USTs. The LPI is used to prioritize USTs so that those with higher LPIs can be monitored closely. A characteristic profile of Army USTs according to construction material, capacity, age, content, and LPI is presented in this paper.The opinions expressed in this paper are those of the authors and do not necessarily reflect the views of the US Department of the Army, nor does the mention of trade names or commercial products constitute endorsement or recommendation for use.  相似文献   
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