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261.
对我国减灾战略的几点建议 总被引:1,自引:1,他引:0
本文从我国的灾害特点徊灾害防治中的困难的角度出发,参照灾害防治的经验教训,提出建立管理国家紧急事物的职能机构;设立防灾科研和教育基金;积极开展国际交流和协作;尽快成立灾害信息情报中心和进行必要的救灾物资储备。 相似文献
262.
武汉市大旅游网络建设研究 总被引:3,自引:0,他引:3
从地理位置、对外经济联系、国内和省内经济地位、旅游资源丰度等方面分析了武汉市发展旅游事业的有利条件;论证了建设以武汉市为中心,向郊区(县)、省内和邻省延伸的旅游网络的必要性和可行性及发展国际旅游的潜力;提出了大力加强景点和基础设施建设,改善周边交通条件,壮大地方航空公司等加快旅游业发展的对策和措施。 相似文献
263.
柳相辉 《中国安全科学学报》1997,(6)
分析了在市场经济条件下,由于政府转变职能,企业转换机制,安全管理面临的四个不相适应,解决办法就是大力发展按市场经济规律运作的职业安全卫生中介组织,并初步探讨了这种中介组织的基本功能、特征及运作方式 相似文献
264.
本文根据我国环境监测系统的工作特点,评述了目前各级环境监测站机构设置的主要形式,剖析了不同的机构设置在促进工作开展、提高工作质量和效率等方面发挥的作用和存在的不足,提出了合理设置业务科室的前提和条件. 相似文献
265.
Venema Henry D. Schiller Eric J. Bass Brad 《Mitigation and Adaptation Strategies for Global Change》1996,1(2):139-165
The ongoing drought in the Sahel region of West Africa highlights the vulnerability of food-producing systems to climate change
and variability. Adaptation to climate should therefore increase the sustainability of agriculture under a long-term drought.
Progress towards sustainability and adaptation in the the Senegal River Basin is hampered by an existing set of social and
ecological relationships that define the control over the means of production and how people interact with their environment.
These relationships are sensitive to the technological inputs and the administration of food production, or the factor bias
in the different policy alternatives for rural development. One option is based on state-controlled, irrigated plantations
to provide rice (Oryza) for the capital, Dakar. This policy emphasizes a top-down management approach, mechanized agriculture and a reliance on
external inputs which strengthens the relationships introduced during the colonial period.
A time series decomposition of the annual flow in the Senegal River at Bakel in Senegal suggests that water resources availability
has been substantially curtailed since 1960, and a review of the water resources budget or availability in the basin suggests
that this policy's food production system is not sustainable under the current climate of the basin. Under these conditions,
this program is exacerbating existing problems of landscape degradation and desertification, which increases rural poverty.
A natural resource management policy offers two adaptation strategies that favour decentralized management and a reduction
of external inputs. The first alternative, “Les Perimetres Irrigués”, emphasizes village-scale irrigation, low water consumption
cereal crops and traditional socio-political structures. The second alternative emphasizes farm-level irrigation and agro-forestry
projects to redress the primary effects of desertification. 相似文献
266.
城市水资源社会再生能力评价模型研究 总被引:1,自引:0,他引:1
为了在城市水资源评价过程中充分考虑城市水资源的社会循环,更好地揭示城市水资源开发利用的潜力,提出了城市水资源社会再生能力概念,并分别建立了城市水资源社会绝对再生能力与相对再生能力的评价指标体系;在此基础上,建立了一种全新的城市水资源评价模型——基于人工神经网络的城市水资源社会再生能力评价模型.该模型在构造评价标准的过程中,通过“虚拟城市”构造模型训练样本;由此将评价问题转化成人工神经网络所擅长的分类问题,并赋予评价结果实际的内涵,使得评价结果更直观且更易于理解.最后,以黄河流域的主要城市为研究对象,对其绝对水资源再生能力与相对水资源再生能力分别进行评价;并与传统的灰色关联方法进行对比;评价结果与实际相吻合。 相似文献
267.
本文试用持续农业的目标来界定持续农业的内涵。持续农业就是具有农业生产可持续性、经济可持续性、生态可持续性和农村社会可持续性的农业。首先分别阐述了持续农业的4个目标,然后就目标之间的相关与独立关系、轻重缓急关系做了分析 相似文献
268.
T.?FredstedEmail author C.?Pertoldi J.?M.?Olesen M.?Eberle P.?M.?Kappeler 《Behavioral ecology and sociobiology》2004,56(4):393-403
The objective of our study was to investigate the spatial distribution and genetic structure of a solitary primate at the microgeographical scale of adjacent local populations. We obtained spatial data and tissue samples for mtDNA analysis from 205 gray mouse lemurs (Microcebus murinus) captured along transects and within 3 grid systems within a 12.3 km2 area in Kirindy Forest, western Madagascar. Our capture data revealed that, even though the forest was continuous, gray mouse lemurs were not evenly distributed, and that daily and maximum dispersal distances were significantly greater in males. The frequency distribution of 22 mtDNA D-loop haplotypes was highly skewed. Nine haplotypes were unique to males, indicating male-mediated gene flow from surrounding areas. The geographic distribution of haplotypes revealed that males were also more dispersed than females. Females with the same haplotype showed a tendency towards spatial aggregation, and the correlation between genetic and geographic distances was higher in females. In several areas of the forest, however, spatially clustered females were not of the same haplotype, and females were not always found in clusters. Hence, in contrast to suggestions from previous studies, matrilineal clustering is not the only way females are socially organized. In addition, our study revealed heterogeneity and patterns in population structure that were not evident at smaller spatial scales, some of which may be relevant for designing conservation strategies.Communicated by C. Nunn 相似文献
269.
Designing Systematic Conservation Assessments that Promote Effective Implementation: Best Practice from South Africa 总被引:4,自引:0,他引:4
ANDREW T. KNIGHT‡‡‡ AMANDA DRIVER†§§§ RICHARD M. COWLING KRISTAL MAZE‡ PHILIP G. DESMET§ AMANDA T. LOMBARD MATHIEU ROUGET††§§§ MARK A. BOTHA† RE F. BOSHOFF‡‡ J. GUY CASTLEY§§ PETER S. GOODMAN KATHY MACKINNON††† SHIRLEY M. PIERCE REBECCA SIMS-CASTLEY‡‡ WARRICK I. STEWART AMREI VON HASE† 《Conservation biology》2006,20(3):739-750
Abstract: Systematic conservation assessment and conservation planning are two distinct fields of conservation science often confused as one and the same. Systematic conservation assessment is the technical, often computer-based, identification of priority areas for conservation. Conservation planning is composed of a systematic conservation assessment coupled with processes for development of an implementation strategy and stakeholder collaboration. The peer-reviewed conservation biology literature abounds with studies analyzing the performance of assessments (e.g., area-selection techniques). This information alone, however, can never deliver effective conservation action; it informs conservation planning. Examples of how to translate systematic assessment outputs into knowledge and then use them for "doing" conservation are rare. South Africa has received generous international and domestic funding for regional conservation planning since the mid-1990s. We reviewed eight South African conservation planning processes and identified key ingredients of best practice for undertaking systematic conservation assessments in a way that facilitates implementing conservation action. These key ingredients include the design of conservation planning processes, skills for conservation assessment teams, collaboration with stakeholders, and interpretation and mainstreaming of products (e.g., maps) for stakeholders. Social learning institutions are critical to the successful operationalization of assessments within broader conservation planning processes and should include not only conservation planners but also diverse interest groups, including rural landowners, politicians, and government employees. 相似文献
270.
The evolution of female social relationships in nonhuman primates 总被引:38,自引:14,他引:38
Elisabeth H. M. Sterck David P. Watts Carel P. van Schaik 《Behavioral ecology and sociobiology》1997,41(5):291-309
Considerable interspecific variation in female social relationships occurs in gregarious primates, particularly with regard
to agonism and cooperation between females and to the quality of female relationships with males. This variation exists alongside
variation in female philopatry and dispersal. Socioecological theories have tried to explain variation in female-female social
relationships from an evolutionary perspective focused on ecological factors, notably predation and food distribution. According
to the current “ecological model”, predation risk forces females of most diurnal primate species to live in groups; the strength
of the contest component of competition for resources within and between groups then largely determines social relationships
between females. Social relationships among gregarious females are here characterized as Dispersal-Egalitarian, Resident-Nepotistic,
Resident-Nepotistic-Tolerant, or Resident-Egalitarian. This ecological model has successfully explained differences in the
occurrence of formal submission signals, decided dominance relationships, coalitions and female philopatry. Group size and
female rank generally affect female reproduction success as the model predicts, and studies of closely related species in
different ecological circumstances underscore the importance of the model. Some cases, however, can only be explained when
we extend the model to incorporate the effects of infanticide risk and habitat saturation. We review evidence in support of
the ecological model and test the power of alternative models that invoke between-group competition, forced female philopatry,
demographic female recruitment, male interventions into female aggression, and male harassment. Not one of these models can
replace the ecological model, which already encompasses the between-group competition. Currently the best model, which explains
several phenomena that the ecological model does not, is a “socioecological model” based on the combined importance of ecological
factors, habitat saturation and infanticide avoidance. We note some points of similarity and divergence with other mammalian
taxa; these remain to be explored in detail.
Received: 30 September 1996 / Accepted after revision: 20 July 1997 相似文献