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961.
曹妃甸围填海工程的环境影响回顾性评价 总被引:3,自引:0,他引:3
围填海回顾性评价是一项涉及面广、内容复杂的分析评价工作。要做出准确、科学的评价,就必须有一套科学的后评价方法和指标体系,评价出项目实际目标与可行性研究阶段预测情况的偏离度,从而比较客观地做出评判。文章建立了围填海工程的海洋生态环境影响回顾性评价指标体系、评价标准与评价方法,并综合运用层次分析法对曹妃甸围填海工程的海洋生态、水动力环境、水质环境和底质环境影响进行回顾性综合评价。该方法克服了传统定性评价的主观性缺点,从而得出比较客观、科学的评价结果,为衡量和分析曹妃甸围填海工程对海洋环境的累积影响及后期围填海工程的环境管理与决策提供了依据。 相似文献
962.
构建科学、准确、有效的量值溯源体系是实验室质量管理的重要内容。在国家市场监督管理总局新发布的《实施强制管理的计量器具目录》中,涉及环境监测用途的类别大幅度减少。在此背景下,研究介绍了量值溯源中检定和校准的差异及适用范围,强调不应将检测作为量值溯源的方式。分类比较了国内现有具备量传能力的计量技术机构,对目前生态环境监测领域量值溯源技术方法与实际使用需求脱节、计量服务供给侧响应不及时的短板进行了总结。建议各专业计量技术委员会加快制修订相关计量技术法规,各计量技术机构及时更新和建立相关计量标准,从而更好地满足环境检测机构对计量器具量值管理的需求。 相似文献
963.
Environmental solutions require a decision-making process that is ultimately political, in that they involve decisions with uncertain outcomes and stakeholders with conflicting viewpoints. If this process seeks broad alignment between the government and public, then reconciling conflicting viewpoints is a key to the legitimacy of these decisions. We show that ecological baselines can be particularly powerful tools for creating a common understanding for public support (legitimacy) and conformity to new rules or regulations (legality) that enable the solution. They are powerful because they move the discussion of solutions from the abstract to the concrete by providing a conceptual model for a common expectation (e.g., restoring habitat). They provide narratives of the past (ecological histories) that readjust the future expectations of individuals on how to perceive and respond to new policy. While ecological baselines offer scientists benchmarks for reinstating ecological functions, they also normalize public and government discussion of solutions. This social normalization of public issues may assist government policy and influence social views, practices, and behaviors that adopt the policy. For science to more effectively inform conservation, we encourage interdisciplinary thinking (science- and human-centered) because it can provide public support and government legitimacy for investing in environmental solutions. 相似文献
964.
Effects of temperature and precipitation on grassland bird nesting success as mediated by patch size
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Grassland birds are declining faster than any other bird guild across North America. Shrinking ranges and population declines are attributed to widespread habitat loss and increasingly fragmented landscapes of agriculture and other land uses that are misaligned with grassland bird conservation. Concurrent with habitat loss and degradation, temperate grasslands have been disproportionally affected by climate change relative to most other terrestrial biomes. Distributions of grassland birds often correlate with gradients in climate, but few researchers have explored the consequences of weather on the demography of grassland birds inhabiting a range of grassland fragments. To do so, we modeled the effects of temperature and precipitation on nesting success rates of 12 grassland bird species inhabiting a range of grassland patches across North America (21,000 nests from 81 individual studies). Higher amounts of precipitation in the preceding year were associated with higher nesting success, but wetter conditions during the active breeding season reduced nesting success. Extremely cold or hot conditions during the early breeding season were associated with lower rates of nesting success. The direct and indirect influence of temperature and precipitation on nesting success was moderated by grassland patch size. The positive effects of precipitation in the preceding year on nesting success were strongest in relatively small grassland patches and had little effect in large patches. Conversely, warm temperatures reduced nesting success in small grassland patches but increased nesting success in large patches. Mechanisms underlying these differences may be patch‐size‐induced variation in microclimates and predator activity. Although the exact cause is unclear, large grassland patches, the most common metric of grassland conservation, appears to moderate the effects of weather on grassland‐bird demography and could be an effective component of climate‐change adaptation. 相似文献
965.
Nicholas L. Ortodossi Ben L. Gilby Thomas A. Schlacher Rod M. Connolly Nicholas A. Yabsley Christopher J. Henderson Andrew D. Olds 《Conservation biology》2019,33(3):580-589
Seascape connectivity (landscape connectivity in the sea) can modify reserve performance in low-energy marine ecosystems (e.g., coral reefs, mangroves, and seagrass), but it is not clear whether similar spatial linkages also shape reserve effectiveness on high-energy, exposed coastlines. We used the surf zones of ocean beaches in eastern Australia as a model system to test how seascape connectivity and reserve attributes combine to shape conservation outcomes. Spatial patterns in fish assemblages were measured using baited remote underwater video stations in 12 marine reserves and 15 fished beaches across 2000 km of exposed coastline. Reserve performance was shaped by both the characteristics of reserves and the spatial properties of the coastal seascapes in which reserves were embedded. Number of fish species and abundance of harvested fishes were highest in surf-zone reserves that encompassed >1.5 km of the surf zone; were located < 100 m to rocky headlands; and included pocket beaches in a heterogeneous seascape. Conservation outcomes for exposed coastlines may, therefore, be enhanced by prioritizing sufficiently large areas of seascapes that are strongly linked to abutting complementary habitats. Our findings have broader implications for coastal conservation planning. Empirical data to describe how the ecological features of high-energy shorelines influence conservation outcomes are lacking, and we suggest that seascape connectivity may have similar ecological effects on reserve performance on both sheltered and exposed coastlines. 相似文献
966.
Cathy Whitlock Daniele Colombaroli Marco Conedera Willy Tinner 《Conservation biology》2018,32(1):84-97
Conservation efforts to protect forested landscapes are challenged by climate projections that suggest substantial restructuring of vegetation and disturbance regimes in the future. In this regard, paleoecological records that describe ecosystem responses to past variations in climate, fire, and human activity offer critical information for assessing present landscape conditions and future landscape vulnerability. We illustrate this point drawing on 8 sites in the northwestern United States, New Zealand, Patagonia, and central and southern Europe that have undergone different levels of climate and land‐use change. These sites fall along a gradient of landscape conditions that range from nearly pristine (i.e., vegetation and disturbance shaped primarily by past climate and biophysical constraints) to highly altered (i.e., landscapes that have been intensely modified by past human activity). Position on this gradient has implications for understanding the role of natural and anthropogenic disturbance in shaping ecosystem dynamics and assessments of present biodiversity, including recognizing missing or overrepresented species. Dramatic vegetation reorganization occurred at all study sites as a result of postglacial climate variations. In nearly pristine landscapes, such as those in Yellowstone National Park, climate has remained the primary driver of ecosystem change up to the present day. In Europe, natural vegetation–climate–fire linkages were broken 6000–8000 years ago with the onset of Neolithic farming, and in New Zealand, natural linkages were first lost about 700 years ago with arrival of the Maori people. In the U.S. Northwest and Patagonia, the greatest landscape alteration occurred in the last 150 years with Euro‐American settlement. Paleoecology is sometimes the best and only tool for evaluating the degree of landscape alteration and the extent to which landscapes retain natural components. Information on landscape‐level history thus helps assess current ecological change, clarify management objectives, and define conservation strategies that seek to protect both natural and cultural elements. 相似文献
967.
Otero Pastor I Casermeiro Martínez MA Ezquerra Canalejoa A Esparcia Mariño P 《Journal of environmental management》2007,85(1):204-214
Landscape evaluation is now widely recognised as a powerful, interdisciplinary, environmental research method. The aim of the present work was to compare two landscape evaluation methods as part of a physical planning process: the cartographic assessment method and the in situ assessment method. This comparison was performed using an area of the Montes de Toledo, in the centre of Spain. Both methods provided similar results for the majority of the landscape units studied. This shows that the cartographic method can be successfully used in landscape evaluation, allowing important savings in terms of fieldwork. However, this is only the case when the information provided by the available maps is sufficiently accurate to allow the correct assignment of coefficients by a panel of experts. 相似文献
968.
The extent of wetland in New Zealand has decreased by approximately 90% since European settlement began in 1840. Remaining
wetlands continue to be threatened by drainage, weeds, and pest invasion. This article presents a rapid method for broad-scale
mapping and prioritising palustrine and estuarine wetlands for conservation. Classes of wetland (lacustrine, estuarine, riverine,
marine, and palustrine) were mapped using Landsat ETM+ imagery and centre-points of palustrine and estuarine sites as ancillary
data. The results shown are for the Manawatu–Wanganui region, which was found to have 3060 ha of palustrine and 250 ha of
estuarine wetlands. To set conservation priorities, landscape indicators were computed from a land-cover map and a digital
terrain model. Four global indicators were used (representativeness, area, surrounding naturalness, and connectivity), and
each was assigned a value to score wetland sites in the region. The final score is an additive function that weights the relative
importance of each indicator (i.e., multicriteria decision analysis). The whole process of mapping and ranking wetlands in
the Manawatu–Wanganui region took only 6 weeks. The rapid methodology means that consistent wetland inventories and ranking
can now actually be produced at reasonable cost, and conservation resources may therefore be better targeted. With complete
inventories and priority lists of wetlands, managers will be able to plan for conservation without having to wait for the
collection of detailed biologic information, which may now also be prioritised. 相似文献
969.
Smith PG 《Environmental management》2007,39(3):338-352
Characteristics of urban natural areas and surrounding landscapes were identified that best explain winter bird use for 28
urban natural areas in southern Ontario, Canada. The research confirms for winter birds the importance of area (size) and
natural vegetation, rather than managed, horticultural parkland, within urban natural areas as well as percent urban land
use and natural habitat in surrounding landscapes. Alien bird density and percent ground feeding species increased with percent
surrounding urban land use. Higher percent forest cover was associated with higher percentages of forest, bark feeding, small
(<20 g) and insectivorous species. Natural area size (ha) was related to higher species richness, lower evenness and higher
percentages of insectivorous, forest interior, area-sensitive, upper canopy, bark feeding, and non-resident species. Higher
number of habitat types within natural areas and percent natural habitat in surrounding landscapes were also associated with
higher species richness. Common, resident bird species dominated small areas (<6.5 ha), while less common non-residents increased
with area, indicative of a nested distribution. Areas at least 6.5 ha and more generally >20 ha start to support some area-sensitive
species. Areas similar to rural forests had >25% insectivores, >25% forest interior species, >25% small species, and <5% alien
species. Indicator species separated urban natural areas from rural habitats and ordination placed urban natural areas along
a gradient between urban development and undisturbed, rural forests. More attention is needed on issues of winter bird conservation
in urban landscapes. 相似文献
970.