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11.
Environmental management and planning are instrumental in resolving conflicts arising between societal needs for economic development on the one hand and for open green landscapes on the other hand. Allocating green corridors between fragmented core green areas may provide a partial solution to these conflicts. Decisions regarding green corridor development require the assessment of alternative allocations based on multiple criteria evaluations. Analytical Hierarchy Process provides a methodology for both a structured and consistent extraction of such evaluations and for the search for consensus among experts regarding weights assigned to the different criteria. Implementing this methodology using 15 Israeli experts—landscape architects, regional planners, and geographers—revealed inherent differences in expert opinions in this field beyond professional divisions. The use of Agglomerative Hierarchical Clustering allowed to identify clusters representing common decisions regarding criterion weights. Aggregating the evaluations of these clusters revealed an important dichotomy between a pragmatist approach that emphasizes the weight of statutory criteria and an ecological approach that emphasizes the role of the natural conditions in allocating green landscape corridors.  相似文献   
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Bamboo in climate change and rural livelihoods   总被引:1,自引:0,他引:1  
Climate change negotiations, assessments, and greenhouse gas inventory guidelines have all but bypassed bamboo. Disallowing stands of tree-like bamboos as forests disparages their function in the carbon (C) cycle, and disregards pillars of smallholder livelihoods. Exposing bamboo not as a panacea, but as an overlooked option for C conservation, sequestration, and adaptation, we screen details of distribution, morphology, growth, physiology, and impacts for pertinence to climate change. Additional to 40 million hectares of existing bamboo forests, many potential host countries for C projects harbor suitable sites. Definitions, methods and default values, such as the root/shoot- ratio, biomass conversion factors, allometric equations and sampling variables need adjusting. Rapid maturation, persistent rhizomes, a rich palette of species, and wind-firmness may mitigate risk. Bamboos can accommodate agro-and urban forestry, and reign in unsustainable shifting cultivation. Distribution functions of bamboo biomass stocks and growths do not deviate drastically from those of trees. If anything, bamboo stocks are slightly lower, and growths slightly higher, with medians of 87 t*ha−1 and 10.5 t*ha−1*yr−1, respectively. However, bamboo’s outstanding socio-economic effects might well determine its future in mitigation and adaptation. Early, continuous yields, selective harvesting on even small parcels of land, low capital and high labor intensity, virtually 100% conversion efficiency to about 1,500 products, and, typically, 75% of economic returns benefiting rural people are advantageous attributes. Regional studies on suitability, silviculture, yields, economics, risk, and C assessment would strengthen bamboo’s function as ‘the poor man’s timber’ and promote its niche as the smallholder’s C sink.  相似文献   
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A distinct external shell abnormality, coarse seam, was found in a high percentage of the pond snail Lymnaea stagnalis (L.) collected near Chernobyl Nuclear Power Plant (NPP), Ukraine. The negative cytogenetical and hematological effects of long-term irradiation on pond snails in the Chernobyl Exclusion Zone have been repeatedly reported; consequently, it has been assumed that radioactivity may also affect shell morphology. However, due to the absence of this shell abnormality in pond snails collected from two radioactive sites in Russia, it can be concluded that the appearance of abnormal shells in snail population near Chernobyl NPP cannot directly be explained by the radioactive contamination.  相似文献   
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During the 2010/2011 Exploration vessel Nautilus expedition to the Mediterranean Sea, samples of Lamellibrachia (Siboglinidae, Annelida) were imaged in situ and collected from hydrothermal vent and methane “cold seeps.” An analysis of these Lamellibrachia and their endosymbiotic thioautotrophic gammaproteobacteria reveals two distinct endosymbiont phylotypes. Phylotype 1 was present in Lamellibrachia specimens from 947 m at the Eratosthenes seamount seep (a seep off Cyprus in the Eastern Mediterranean), and Phylotype 2 was found in siboglinids from 618 m at a hydrothermal vent within Palinuro volcanic complex in Tyrrhenian Sea. Both phylotypes coexist in siboglinids at 1,036 m from the Palmachim disturbance, a cold seep in the Eastern Mediterranean’s Levantine basin. Our results, combined with existing knowledge of siboglinid host and endosymbiotic bacteria biogeography, reveal that two major groups of endosymbionts coexist within lamellibranchids and escarpids. The phylogenetic clustering of these bacteria is primarily influenced by geographic location, rather than selection by the siboglinid host.  相似文献   
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We have analyzed an influence of the traditional agricultural system techniques on the soil organic matter dynamics using the model of carbon and nitrogen cycling in forest ecosystems EFIMOD linked with the model of SOM dynamics ROMUL. Forest stands on the loamy soddy-podzolic soils (Alfisoils) located in the Central European Russia have been taken for the case study. The following land-use management scenarios were simulated: (a) slash-and-burn system with 3 years for crops and 120, 60 and 25 years for forest; (b) three-field crop rotation system with organic fertilization (dung) every 3 and 9 years and the same rotation without fertilization; and (c) short-term field-forest shifting system with 10 years for crops and 10 and 25 years for forest. Analysis of the results showed that the frequency of agricultural use in mixed field-forest land-use systems was crucial for soil organic matter dynamics. Under the short interval between agriculture, the stocks of all soil organic matter pools decreased. Under all scenarios except the three-field crop rotation with fertilization and the slash-and-burn system with 120 years for forest, a strong reduction of soil organic matter occurred after 30-130 years of the agricultural impacts. The highest reduction rates were modelled under the short-term field-forest shifting system and three-field rotation without fertilization. Fertilization led to stabilization of soil organic matter pools and gave a possibility for a long time stable agricultural use.  相似文献   
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