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141.
I. V. Emelyanova G. E. Donald D. J. Miron D. A. Henry M. G. Garner 《Environmental Modeling and Assessment》2009,14(4):449-465
A probabilistic Bayesian method called weights of evidence (WofE) was used to develop a synthetic dataset of cattle farm locations at a national scale across Australia. The synthetic
dataset was required for the modelling of livestock movements with a view to assessing biosecurity implications. The WofE method is based on the analysis of spatial relationships between evidential patterns with respect to an event, such
as the actual location of a farm. The evidential patterns of cattle farms were derived from maps of land use, land tenure,
drainage systems, roads, settlements and long-term averaged rainfall. These evidential patterns were used for delineating
and ranking land areas suitable for cattle farming. For each evidential pattern statistics such as a positive weight, a negative weight and a contrast were calculated for estimating the degree of correlation between the evidential patterns and known farm locations. The integrated
evidential patterns of known farms were then used for estimating posterior probabilities and splitting land into five different
classes according to its suitability for farming.
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I. V. EmelyanovaEmail: |
142.
功能区噪声自动监测点位布设探讨 总被引:1,自引:0,他引:1
分析了各类功能区噪声的特点,提出自动监测点位布设的基本原则。对传声器水平距离和垂直高度的确定做了相关比对实验,结果表明,传声器水平距离选择距反射面不小于3 m,垂直高度为4~5m时,能较好地反映该功能区受环境噪声影响状况。 相似文献
143.
144.
The scientific literature regarding HEMS (Helicopter Emergency Medical Service) planning lacks a method for defining optimal sites for helipads that takes into account risk distribution and hospital location. Such a method could minimise overall rescue time in emergency situations. In this paper a method that supports the decisions taken by disaster planners and managers is developed, focusing on the quantification of necessary air resources for the management of some probable calamities. Given a region characterised by a natural and non-natural disaster risk map, along with a comprehensive transport system (also characterised by a risk map), a set of emergency destinations (hospitals), a set of heliports/helipads dislocated on the territory and a number of available HEMS rotorcraft, the aim of the paper is to assess the adequacy of the VTOL/FATO (Vertical Take-Off and Landing/Final Take-Off and Landing Area) system in order to deal with a set of possible emergencies. 相似文献
145.
We investigated the effects of ambient ultraviolet (UV) radiation on (i) the performance and chemistry of soybean plants, (ii) the performance of Spodoptera frugiperda and (iii) the foraging behavior of the herbivore's natural enemy Cotesia marginiventris which exploits herbivore-induced plant volatiles (VOC) for host location. The accumulation of protective phenolics was faster in plants receiving ambient UV than in controls exposed to sun light lacking UV. Accordingly, isorhamnetin- and quercetin-based flavonoids were increased in UV exposed plants. No UV effects were found on the performance and feeding behavior of S. frugiperda. Herbivore-damaged plants emitted the same VOC when grown under ambient or attenuated UV for 5, 10 or 30 days. Consequently, C. marginiventris was attracted but did not discriminate between exposed and unexposed soybeans. In summary, ambient UV radiation affected soybean morphology and physiology but did not destabilize interactions between trophic levels. 相似文献
146.
Host location behavior of Cotesia plutellae Kurdjumov (Hymenoptera: Braconidae) in ambient and moderately elevated ozone in field conditions 总被引:1,自引:0,他引:1
Pinto DM Himanen SJ Nissinen A Nerg AM Holopainen JK 《Environmental pollution (Barking, Essex : 1987)》2008,156(1):227-231
In field O3-enrichment experiments increased herbivore densities have been reported, which could be due to negatively affected host location behavior of natural enemies. We addressed the impact of doubling background O3 on the host location of the parasitoid Cotesia plutellae by conducting 24-h trials in an open-air O3-fumigation system during two consecutive years. Two circles (radii 1.40 and 4.00 m) of Plutella xylostella-infested potted cabbage plants were placed in the O3 and ambient plots. Female wasps were released into each plot from the center, and observed 5 times over a 24-h period to assess their host location capability. Thereafter, plants were kept in laboratory conditions until larvae pupation to determine parasitism rates. No significant differences were detected between ambient and O3-enriched environments either in the number of wasps found in the field, or in the percentages of parasitized larvae. This suggests that moderately elevated O3 will not affect the behavior of this parasitoid. 相似文献
147.
我国林业发展的区域差异分析 总被引:1,自引:0,他引:1
采用偏离—份额和区位熵分析法,以2003—2006年为考察期,以全国为参照系,对我国31个省(区、市)的林木培育和种植、竹木采运、林产品的行业专业化程度、产业结构、竞争力的区域差异进行了分析。在上述分析基础上,结合全国和地区的林业发展状况,提出调整和优化林业产业结构、促进林业发展和改善林业经济增长质量的对策及建议。 相似文献
148.
油气产业集群识别为完善区域油气产业发展规划和明确不同区域油气产业集群发育程度差异提供科学依据。本文油气产业集群识别包括产业集群地理边界确定和产业集群辨认,选择行政区划省(直辖市或自治区)作为油气产业集群识别的地理边界;基于企业数量区位熵、产业产值区位熵和就业区位熵提出复合区位熵概念CLQ,并据此将我国12个油气资源富集省区依油气产业集群发育程度辨认(识别)为三个梯队:第一梯队包括新疆、黑龙江、辽宁、天津、山东、甘肃6省区,油气产业上、下游均不同程度地发育产业集群;第二梯队包括陕西、吉林、河北、四川、青海5省区,油气产业上、下游并非均发育产业集群;第三梯队为河南,油气产业上、下游均不发育产业集群;进一步计算12省区油气产业上、下游的CLQ差值,结果表明,总体上我国这12个油气资源富集省区油气产业下游相对于上游发育不足,油气产业链出现"上游大,下游小"的畸形格局。 相似文献
149.
自然灾害防治综合立法研究:定位、理念与制度 总被引:1,自引:0,他引:1
近年来,国家高度重视防灾减灾救灾,发布了防灾减灾救灾系列重要文件,实施了应急管理体制机制重大改革举措。落实防灾减灾救灾新思想新理念新要求,契合国家发展改革的现实需要,应加紧推进自然灾害防治综合立法。自然灾害防治综合立法的定位是自然灾害防治的基本法、应急管理的特别法、公共安全的支撑法。自然灾害防治综合立法应在坚持以人民为中心理念、风险防范理念、综合防治理念、权利保护理念的基础上,确立自然灾害风险隐患排查、危险区避让及搬迁转移、自然灾害科普、自然灾害防治社会参与、自然灾害保险等制度,为推进我国自然灾害防治体系和防治能力现代化提供法制保障。 相似文献
150.