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11.
本研究利用生物气候、地形、底质类型、海温等环境因子和红树林分布数据建立了福建省红树林分布模型,基于最大熵方法分析了福建省沿岸红树林潜在适生区的空间分布.根据模型输出结果对福建省红树林的生境适宜性进行了评估,识别了影响红树林分布的关键环境因子及其适生值区间,并通过空间叠加分析获取了福建省红树林保护与修复的优先区与空缺区域.结果表明,影响福建省红树林适生区分布格局的主要环境因子包括海表温度、气温和降水等,福建省红树林潜在适生区主要位于沙埕港-三沙湾-兴化湾沿岸、泉州湾-厦门湾-九龙江口沿岸、漳江口-东山湾沿岸等地,其中最优适生区面积约为91km2.全省共识别出8处红树林保护与修复的优先区域,现存红树林保护率约为64.4%,保护修复空缺主要出现在沙埕港、三沙湾、罗源湾、福清湾等处,研究结论可为未来福建省红树林保护和修复行动提供科学参考. 相似文献
12.
Several theoretical, analytical, and institutional difficulties have impeded the development and application of the assessment of cumulative environmental impacts. Watershed development on coastal wetlands offers an ideal context for evaluating the land disturbance target approach to cumulative impact assessment. A model land use planning system involving a time series approach was developed for Elkhorn Slough in California. The approach included four major components: evaluation of erosion susceptibility, measurement of land disturbance, establishment of a land disturbance target, and a comparison of existing and target land disturbance values. Further research is needed to test the transferability of the approach in a wide range of coastal watersheds and to verify the applicability of the methods to other cumulative impact problems. 相似文献
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Although the process of documenting compliance with NEPA (the National Environmental Policy Act) requires no drastic revisions, it can be managed more rigorously. Suggestions for revision can be grouped under five major steps: 1) getting a complete proposal from the applicant; 2) getting the decision-making process onto the right decision-making path; 3) modifying the applicant's proposal 4) going down a shorter path through the EA/FONSI (environmental assessment and finding of no significant impact) or through categorical exclusion review; and 5) going down the longer path through the EIS. Step 2 is perhaps the most critical, because there a decision must be made whether to write an EA/FONSI or an EIS, on the basis of whether the proposal would “significantly affect … the … environment.” In the past, this decision has not always been made promptly or rigorously. Accordingly, we suggest that the agency responsible for NEPA compliance should develop a system (a “black box”), consisting of a core group of specialists working with an interdisciplinary team, using sophisticated techniques for modeling impacts and directing both their research and their writing according to the concept of significance. By determining more efficiently and reliably whether the impacts of a proposal would be significant, such an approach would improve management of the total process. 相似文献
15.
Rice WE 《Environmental monitoring and assessment》2004,99(1-3):251-257
A sub-surface desert water harvester was constructed in the sagebrush steppe habitat of south-central Idaho, U.S.A. The desert
water harvester utilizes a buried micro-catchment and three buried storage tanks to augment water for wildlife during the
dry season. In this region, mean annual precipitation (MAP) ranges between about 150–250 mm (6″–10″), 70% of which falls during
the cold season, November to May. Mid-summer through early autumn, June through October, is the dry portion of the year. During
this period, the sub-surface water harvester provides supplemental water for wildlife for 30–90 days, depending upon the precipitation
that year. The desert water harvester is constructed with commonly available, “over the counter” materials. The micro-catchment
is made of a square-shaped, 20 mL. “PERMALON” polyethylene pond liner (approximately 22.9 m × 22.9 m = 523 m2) buried at a depth of about 60 cm. A PVC pipe connects the harvester with two storage tanks and a drinking trough. The total
capacity of the water harvester is about 4777 L (1262 U.S. gallons) which includes three underground storage tanks, a trough
and pipes. The drinking trough is refined with an access ramp for birds and small animals. The technology is simple, cheap,
and durable and can be adapted to other uses, e.g. drip irrigation, short-term water for small livestock, poultry farming
etc. The desert water harvester can be used to concentrate and collect water from precipitation and run-off in semi-arid and
arid regions. Water harvested in such a relatively small area will not impact the ground water table but it should help to
grow small areas of crops or vegetables to aid villagers in self-sufficiency. 相似文献
16.
Conservation and management applications of the REEF volunteer fish monitoring program 总被引:2,自引:0,他引:2
Pattengill-Semmens CV Semmens BX;Reef Environmental Education Foundation 《Environmental monitoring and assessment》2003,81(1-3):43-50
The REEF Fish Survey Project is a volunteer fish monitoring program developed by the Reef Environmental Education Foundation (REEF). REEF volunteers collect fish distribution and abundance data using a standardized visual method during regular diving and snorkeling activities. Survey data are recorded on preprinted data sheets that are returned to REEF and optically digitized. Data are housed in a publicly accessible database on REEF's Web site (http: //www.reef.org). Since the project's inception in 1993, over 40,000 surveys have been conducted in the coastal waters of North America, tropical western Atlantic, Gulf of California and Hawaii. The Fish Survey Project has been incorporated into existing monitoring programs through partnerships with government agencies, scientists, conservation organizations, and private institutions. REEF's partners benefit from the educational value and increased stewardship resulting from volunteer data collection. Applications of the data include an evaluation of fish/habitat interactions in the Florida Keys National Marine Sanctuary, the development of a multi-species trend analysis method to identify sites of management concern, assessment of the current distribution of species, status reports on fish assemblages of marine parks, and the evaluation of no-take zones in the Florida Keys. REEF's collaboration with a variety of partners, combined with the Fish Survey Project's standardized census method and database management system, has resulted in a successful citizen science monitoring program. 相似文献
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详细介绍了“城市空气质量日报自动发布系统”的开发背景和开发过程 ,并对系统整体的架构和所用到的技术作了针对性的说明 ,阐明了作者对此类系统的前景和发展方向的看法。 相似文献
19.
Darek J. Nalle Jeffrey L. Arthur Claire A. Montgomery John Sessions 《Environmental Modeling and Assessment》2002,7(2):99-105
An optimization model for land reservation was developed that explicitly selects parcels in the most compact or contiguous manner possible while meeting habitat requirements and a budget limitation. The model was used to compare the effects of an existing reserve network on future parcel spatial locations and total cost. Using habitat and land value data from Josephine County, Oregon, it was found that a system of existing reserves created by various policies and overseen by different agencies can decrease future reserve compactness and contiguity, and increase total cost. This work suggests that coordinated planning can result in more efficient conservation efforts for less cost. 相似文献
20.
Wojciech Mniszek 《Environmental monitoring and assessment》2001,68(2):197-207
The aim of the study was to develop a sampling method aimed at individual sampling of mercury vapor and subsequent individualexposure assessment of the worker. Hopcalite available fromInowrocawskie Zakady Chemiczne (in Poland) was founduseful for mercury vapor sampling in active and passive individual samplers. However the sampling rate determined forpassive sampler in steady-state laboratory chamber cannot be usedunder fluctuating conditions of mercury vapor concentration andair movement typical for field measurement. In order to check comparativeness of passive and active sampling methods, sampleswere taken in the same time and individual samplers fixed toworker's clothes were used. Mercury vapor concentration wasmeasured at two chloralkali industries in Poland and the resultswere presented. Excessive exposure in both industries wasconfirmed by finding elevated mercury concentration in urinesamples from the workers. 相似文献