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161.
The dynamics of habitat distribution in two bird species differing in the level of site tenacity—willow warbler (relatively tenacious) and little bunting (more flexible)—were studied at the boundary of the northern taiga and forest–tundra zones over ten years. The distribution pattern proved to be more uniform in the willow warbler than in the little bunting. Both species occupied their habitats according to a well-known scheme: initially, the birds settled in their favorable floodplain habitats and later; when their abundance increased, in less preferable habitats (terraces above the floodplain, moss bogs, and the tundra). In the case of willow warbler, the process of occupying the floodplain was stepwise: bird density increased sharply, remained at the same level in the next year, then increased again, etc. In the case of little bunting, the degree of floodplain occupation by birds remained high, except for the years when high spring floods interfered with bird settling. 相似文献
162.
填埋场底土污染物浓度实测值和理论解的比较 总被引:3,自引:0,他引:3
为了研究现场条件下污染物在粘性土中的运移机理,对运行13年的苏州七子山填埋场进行了钻孔取样.通过对土样进行分层切片、加去离子水混合并结合室内小型离心机分离,得到了填埋场底土中Cl-,Na+及COD的孔隙水浓度.将室内试验测试值和一维扩散理论进行了比较,结果表明,实测浓度剖面与扩散曲线差别较大,可见水力梯度引起的对流和机械弥散作用比分子扩散作用来得重要.将实测值与一维对流弥散解析解的计算值亦进行了比较,结果表明试验数据较为发散,但可以采用一维对流弥散理论进行大致的拟合,从而可得到运移参数的取值范围.进一步的理论预测表明,当填埋场运行30年之后,Cl-的影响深度可达到10 m以上.为了防止和延缓渗滤液污染物的进一步运移,填埋场应采取有效措施阻止渗滤液的扩散. 相似文献
163.
SANTTU KAREKSELA ATTE MOILANEN SEPPO TUOMINEN JANNE S. KOTIAHO 《Conservation biology》2013,27(6):1294-1303
Globally expanding human land use sets constantly increasing pressure for maintenance of biological diversity and functioning ecosystems. To fight the decline of biological diversity, conservation science has broken ground with methods such as the operational model of systematic conservation planning (SCP), which focuses on design and on‐the‐ground implementation of conservation areas. The most commonly used method in SCP is reserve selection that focuses on the spatial design of reserve networks and their expansion. We expanded these methods by introducing another form of spatial allocation of conservation effort relevant for land‐use zoning at the landscape scale that avoids negative ecological effects of human land use outside protected areas. We call our method inverse spatial conservation prioritization. It can be used to identify areas suitable for economic development while simultaneously limiting total ecological and environmental effects of that development at the landscape level by identifying areas with highest economic but lowest ecological value. Our method is not based on a priori targets, and as such it is applicable to cases where the effects of land use on, for example, individual species or ecosystem types are relatively small and would not lead to violation of regional or national conservation targets. We applied our method to land‐use allocation to peat mining. Our method identified a combination of profitable production areas that provides the needed area for peat production while retaining most of the landscape‐level ecological value of the ecosystem. The results of this inverse spatial conservation prioritization are being used in land‐use zoning in the province of Central Finland. 相似文献
164.
《International Journal of Sustainable Engineering》2013,6(1):23-30
Today, the issue of site selection for industrial units in developing countries which are poor in wood resources is considered as a vital matter and it is one of the key measures in the process of building industrial and giving service units. In every country there are some provinces and states which are more useful than other parts owing to primary infrastructures and facilities for industrialisation. As one of the suitable provinces of Iran, thanks to its lignocelluloses resources with 1,822,696 tons of exploitable waste, Golestan Province has a very good potential for building lignocelluloses products mills, such as fluting paper. For this end, in 2010, effective indices in fluting paper mill establishment were recognised in Golestan Province. Results showed that materials and products were the most important main indices and the preparation cost of raw materials was the most important sub-index. Finally, questionnaires were prepared for the best site selection and choices were evaluated according to the structure of interests and costs. The results of calculations performed through analytical hierarchy processes and in Expert Choice Software indicated that Gonbad City had the highest interest/cost ratio, and therefore, it is the best place for the establishment of floating paper mills from agricultural wastes in Golestan Province. 相似文献
165.
166.
Abstract: Systematic conservation planning typically requires specification of quantitative representation targets for biodiversity surrogates such as species, vegetation types, and environmental parameters. Targets are usually specified either as the minimum total area in a conservation-area network in which a surrogate must be present or as the proportion of a surrogate's existing spatial distribution required to be in the network. Because the biological basis for setting targets is often unclear, a better understanding of how targets affect selection of conservation areas is needed. We studied how the total area of conservation-area networks depends on percentage targets ranging from 5% to 95%. We analyzed 12 data sets of different surrogate distributions from 5 regions: Korea, Mexico, Québec, Queensland, and West Virginia. To assess the effect of spatial resolution on the target-area relationship, we also analyzed each data set at 7 spatial resolutions ranging from 0.01°× 0.01° to 0.10°× 0.10°. Most of the data sets showed a linear relationship between representation targets and total area of conservation-area networks that was invariant across changes in spatial resolution. The slope of this relationship indicated how total area increased with target level, and our results suggest that greater surrogate representation requires significantly more area. One data set exhibited a highly nonlinear relationship. The results for this data set suggest a new method for setting targets on the basis of the functional form of target-area relationships. In particular, the method shows how the target-area relationship can provide a rationale for setting targets solely on the basis of distributional information about surrogates. 相似文献
167.
Zhijian Liu Haiyang Liu Hang Yin Rui Rong Guoqing Cao Qihong Deng 《Frontiers of Environmental Science & Engineering》2021,15(3):36
168.
B.J. Harris B. Reliford G. Annette K. Jennings 《Journal of environmental science and health. Part. B》2013,48(5):969-985
Abstract Pendimethalin herbicide (PROWL®480 EC) spray drift was determined from ground applications representing the highest rate applied to corn in eastern Canada. A novel drift collector pattern was laid out on the ground immediately before herbicide application. Most of the drift collectors were located downwind of the application target area. The maximum labelled rate of 1.68 kg ai/Ha was applied on 2 occasions on separate sites. In both applications, drift collector cards indicated that concentrations of pendimethalin were not detectable outside the target zone (<0.01 μg/cm2) at or beyond the 10 metre drift collector stations. Risk assessment calculations indicated that non‐target organisms would not be at significant risk from off‐site movement of pendimethalin. 相似文献
169.
Abstract: Biodiversity is too complex to measure directly, so conservation planning must rely on surrogates to estimate the biodiversity of sites. The species richness of selected taxa is often used as a surrogate for the richness of other taxa. Surrogacy values of taxa have been evaluated in diverse contexts, yet broad trends in their effectiveness remain unclear. We reviewed published studies testing the ability of species richness of surrogate taxa to capture the richness of other (target) taxa. We stratified studies into two groups based on whether a complementarity approach (surrogates used to select a combination of sites that together maximize total species richness for the taxon) or a richness‐hotspot approach (surrogates used to select sites containing the highest species richness for the taxon) was used. For each comparison of one surrogate taxon with one target, we used the following predictor variables: biome, spatial extent of study area, surrogate taxon, and target taxon. We developed a binary response variable based on whether the surrogate taxon provided better than random representation of the target taxon. For studies that used an evaluation approach that was not based on better than random representation of target taxa, we based the response variable on the interpretation of results in the original study. We performed a categorical regression to elucidate trends in the effectiveness of surrogate taxa with regard to each of the predictor variables. A surrogate was 25% more likely to be effective with a complementarity approach than with a hotspot approach. For hotspot‐based approaches, biome, extent of study, surrogate taxon, and target taxon significantly influenced effectiveness of the surrogate. For complementarity‐based approaches, biome, extent, and surrogate taxon significantly influenced effectiveness of the surrogate. For all surrogate evaluations, biome explained the greatest amount of variation in surrogate effectiveness. From most to least, extent, surrogate taxon, and target taxon explained the most variation after biome. Surrogate taxa were most effective in grasslands and in some cases boreal zones, deserts, and tropical forests; surrogate taxa also were more effective in studies examining larger areas. Herpetofauna were the most effective taxon as both surrogate and target when a richness‐hotspot approach was used; however, herpetofauna were analyzed in fewer studies, so this result is tentative. For complementarity approaches, taxa that are easy to measure and tend to have a large number of habitat specialists distributed collectively across broad environmental gradients (e.g., plants, birds, and mammals) were the most effective surrogates. 相似文献
170.