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691.
An analytic network process approach for locating undesirable facilities: an example from Istanbul, Turkey 总被引:5,自引:1,他引:4
Locating an undesirable facility is a sophisticated problem, for the evaluation procedures involve several objectives and the solution to the problem calls for some compromises to be made between probable conflicting criteria. This paper addresses the problem of undesirable facility location selection using the analytic network process (ANP), a multi-criteria decision-making technique. The ANP technique enables us to consider both qualitative and quantitative criteria as well as the interdependencies and feedbacks. A number of criteria (benefits, opportunities, costs and risks) and their sub-criteria are considered for siting a new facility with which this study has dealt. The questions of what criteria would be considered and what the interdependencies between these criteria and their weights would be were discussed and determined via interviews with some competent authorities of the Istanbul Municipality and of two environmental organizations. Four representative locations were evaluated and the most convenient one was selected. This was followed by the sensitivity analyses of the results. 相似文献
692.
This study presents a meta-analysis of a collective dataset describing the succession from abandoned fields to semi-natural
grassland and heathland vegetation over the past century. The study objectives were to develop a method for statistical discrimination
between abandoned fields and semi-natural habitats and to analyze the probability that an abandoned field had developed into
a semi-natural habitat. A statistical classification model was developed, based on lists of vascular plants from 2059 plots
from Danish semi-natural grasslands and heathlands, and abandoned fields of varying age. This model was shown to discriminate
effectively between abandoned fields and semi-natural habitats, and it was found to be potentially useful for the detection
of abandoned fields approaching semi-natural vegetation. We suggest that the model may help clarify restoration targets and
assess biological condition in formerly cultivated areas. Statistical modeling revealed that succession age, period of abandonment
and succession trajectory had significant effects on the probability that abandoned fields reached the semi-natural phase.
Our study indicates that restoration projects targeting grassland and heathland should take local species pools and soil fertility
into account.
Nomenclature: Species names follow Flora Europaea (Tutin and others 1964–1993). 相似文献
693.
城市绿地系统建设的生态对策——以长春市为例 总被引:15,自引:0,他引:15
曹勇宏 《城市环境与城市生态》2001,14(5):9-11
绿色空间是所有城市实现可持续发展的物质载体和市民接触自然的主要场所。几乎所有城市不同程度地存在着绿地被挤占、破坏、污染严重等各种问题。以长春市为例,提出了大城市进行绿地系统建设的总量控制、构建经色空间网络体系等生态对策,并针对大城市内部用地紧张的矛盾,探讨了市区内部的绿化用地潜力。 相似文献
694.
J. G. Castley J.-S Bruton G. I. H. Kerley A. McLachlan 《Journal of Coastal Conservation》2001,7(1):57-70
The endozoochorous dispersal of seeds by mammals and birds between distinct vegetation communities was assessed to determine
the importance of these processes in coastal dune field management. Isolated pockets of thicket vegetation (bush-pockets)
within a large coastal dune field provided the opportunity to study vertebrate seed dispersal and its contribution to their
origin and maintenance. Mammalian and avian faeces were collected for the quantification of seeds dispersed via endozoochory.
Birds and mammals showed considerable overlap, dispersing intact seeds of 17 and 29 plant species, respectively, but mammals
dispersed a greater diversity and size range than birds. Extrapolation of mammalian faecal data indicates an annual input
of 23 million intact seeds to the dune field. Significantly more seeds are deposited by mammals and birds in the bush-pockets
than on open sand, and birds deposited greater numbers of seeds nearer the seed source. Zoochory appears to be critical for
the maintenance of the bush-pocket habitats through the dispersal of climax woody plant species into the dune field. Directional
dispersal by birds and mammals to the bush-pockets is considered to be responsible for the maintenance and possible origin
of these bush-pockets. The high number of exotic plant propagules dispersed by both avian and mammalian zoochory highlights
the importance of management of the Alexandria Coastal Dunefield (ACD) beyond the reserve boundaries. In a dynamic system
such as the ACD which is within a declared nature reserve, the continued existence of the bush-pockets may depend on the maintenance,
beyond the reserve boundaries, of a reservoir of not only plant material but vertebrate dispersers as well. 相似文献
695.
本文对建设校园网的前期准备工作作了详细的阐述,对各阶段的工作详细作了规划,对于准备建设校园网的学校具有指导意义. 相似文献
696.
This paper introduces a new portable intelligent electronic nose system developed especially for measuring and analysing livestock
and poultry farm odours. It can be used in both laboratory and field. The sensor array of the proposed electronic nose consists
of 14 gas sensors, a humidity sensor, and a temperature sensor. The gas sensors were especially selected for the main compounds
from the livestock farm odours. An expert system called “Odour Expert” was developed to support researchers’ and farmers’
decision making on odour control strategies for livestock and poultry operations. “Odour Expert” utilises several advanced
artificial intelligence technologies tailored to livestock and poultry farm odours. It can provide more advanced odour analysis
than existing commercially available products. In addition, a rank of odour generation factors is provided, which refines
the focus of odour control research. Field experiments were conducted downwind from the barns on 14 livestock and poultry
farms. Experimental results show that the predicted odour strengths by the electronic nose yield higher consistency in comparison
to the perceived odour intensity by human panel. The “Odour Expert” is a useful tool for assisting farmers’ odour management
practises.
Supported by Ontario Pork, Natural Sciences and Engineering Research Council (NSERC), and Ontario Ministry of Agriculture
and Food (OMAF) of Canada. 相似文献
697.
698.
699.
Dilini Abeygunawardane Angela Kronenburg García Zhanli Sun Daniel Müller Almeida Sitoe Patrick Meyfroidt 《Ambio》2022,51(6):1535
Actor-level data on large-scale commercial agriculture in Sub-Saharan Africa are scarce. The peculiar choice of transnational investing in African land has, therefore, been subject to conjecture. Addressing this gap, we reconstructed the underlying logics of investment location choices in a Bayesian network, using firm- and actor-level interview and spatial data from 37 transnational agriculture and forestry investments across 121 sites in Mozambique, Zambia, Tanzania, and Ethiopia. We distinguish four investment locations across gradients of resource frontiers and agglomeration economies to derive the preferred locations of different investors with varied skillsets and market reach (i.e., track record). In contrast to newcomers, investors with extensive track records are more likely to expand the land use frontier, but they are also likely to survive the high transaction costs of the pre-commercial frontier. We highlight key comparative advantages of Southern and Eastern African frontiers and map the most probable categories of investment locations.Supplementary informationThe online version contains supplementary material available at 10.1007/s13280-021-01682-z. 相似文献
700.