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961.
新型城镇化与非正规就业:规模、格局及社会融合 总被引:2,自引:0,他引:2
中国城镇化由偏重数量转向更加注重质量的新型城镇化,促进农村转移人口市民化、提高就业质量成为城镇化发展的重要目标,疫情影响下非正规就业问题更为突出。论文从新型城镇化与非正规就业的关系出发阐释非正规就业人口的历史产生和发展要求,基于人口普查和《中国劳动力动态调查》测度了中国城镇非正规就业的规模和格局特征,总结了非正规就业者当前面临的社会融合难题,并提出发展思路和路径。结果发现:① 城镇化与非正规就业之间关系密切,非正规就业为城镇化过程中农村转移人口提供大量就业机会,缓解了城镇就业压力。以人为本的新型城镇化需要关注非正规就业模式,以促进农业转移人口市民化和社会融合。② 经多源数据估算,中国城镇非正规就业占城镇总就业的33.2%~44.7%,就业人数达1.38亿~1.55亿,以隐性就业部分为主。在空间分布上总体呈现东、中、西逐渐减少的特征;在雇佣类型上以从事各类非正规工作的被雇型就业为主;行业结构主要集中在批发和零售贸易及餐饮业,居民服务、修理和其他服务业与制造业等。③ 非正规就业者主要面临职业困境、户籍限制、公共服务差距、风险应对能力弱等问题,需要通过完善就业服务体系等改革,提升就业质量,推动市民化和社会融合。 相似文献
962.
中国西北水资源的脆弱性 总被引:8,自引:3,他引:8
The vulnerability of water resources in Northwest China were described in terms of the sensitivity and adaptability of water resource systems effected by climate change and human activities. Most measures that reduce the vulnerability are closely linked with decreasing the sensitivity of climate change or human activity. In other words, the interaction of climate factors and human activity may either exacerbate or mitigate the vulnerability of water resources. Studying both positive and negative events in terms of sustainable utilization of water resources in the past, may establish the sound strategic base in regulating further human activity. The knowledge and correct awareness of recent and future tendencies of hydro-climatic condition may serve as an imperative scientific base for taking such actions as: 1) undertaking structural and non-structural (e.g., policy, law, and forecasting) measures in a reasonable way; 2) coordinating and allocating both differences of time and space between inflow water and water use and between water yield area and water assumption area as well. 相似文献
963.
Sarah J. Halvorson 《The Professional geographer》2003,55(2):120-133
Water‐related diseases continue to pose major threats to children's survival and well‐being in many places in the developing world. This article develops a theoretical perspective on the ways in which children's vulnerability to water‐related disease hazard is produced within the everyday circumstances of livelihood and child care. Central to this analysis is the role that household resources play in mediating or shaping particular microenvironments of health risk. Further, the effects of local geographies of gender on how household resources are accessed and on how child care is structured are examined. Children's vulnerability is evaluated in a community in the District of Gilgit in northern Pakistan, a region presently undergoing tremendous social and economic transformation. The case study highlights household‐level response and adaptation to child health risks associated with diarrheal disease transmission and infection in this mountain environment. The case study draws from ethnographic fieldwork involving qualitative household microstudies and interviewing to elicit mothers' resource and risk‐response strategies in the context of changes in livelihood systems and household dynamics. 相似文献
964.
John R. Lindsay 《Natural Hazards》2003,28(2-3):291-304
The growing appreciation of mitigation is highlighting theneed to develop a better understanding of what makes some people more vulnerable tothe impacts of a disaster. Health researchers have asked a similar question regarding thevarying vulnerability to illness within a population. This has lead to the identification of a setof social, physical and economic factors that are now referred to as the determinants of health.These factors are the same as those commonly associated with disaster vulnerability. Recognizingthat these same concepts are being applied in both the health and disaster management contextspresents an opportunity to also achieve a shared objective of reducing vulnerability withina population. 相似文献
965.
966.
967.
Earthquake Damage Scenarios of the Building Stock of Potenza (Southern Italy) Including Site Effects 总被引:3,自引:0,他引:3
Mauro Dolce Angelo Masi Maria Marino Marco Vona 《Bulletin of Earthquake Engineering》2003,1(1):115-140
Damage scenarios relevant to the building stock of the town of Potenza, Southern Italy, are presented. A procedure for the
preparation of scenarios has been purposely set up. In the first step, the inventory of the building stock has been made.
Location and characteristics of buildings have been obtained from a survey carried out after the 1990 Potenza earthquake and
further updated in 1999. In the second step, the absolute vulnerability of the buildings has been evaluated. A hybrid technique
has been used, where typological analyses and expert judgement are combined together. Beyond the classes of vulnerability
A, B and C of the MSK scale, the class D of EMS98 scale, for the less vulnerable buildings, has been considered. The third
step has been the selection of the reference earthquakes by including also local amplification effects. Two events with 50
and 475 years return periods have been chosen as representative, respectively, of a damaging and of a destructive seismic
event expected in Potenza. The sites that may exhibit important amplification effects have been identified using the first
level method of the TC4 Manual. Damage scenarios of dwelling buildings have been prepared in the fourth step and reported
in a GIS. They are relevant to the selected reference earthquakes, taking into account or not site effects. The generally
low vulnerability of buildings results in a limited number of damaged buildings for the lower intensity earthquake, and of
collapsed buildings, for the higher intensity earthquake. The influence of site effects on the damage distribution is significant.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
968.
Whole-ecosystem experiments may reach statistical pertinence when reference and treatment sites are compared. Therefore at least two similar systems must be found. To this aim we tried to answer the question if the hyporheic zones of both streams have similar features. We postulated that both streams would be unsuitable for a comparison in an ecosystem experiment if the structure of their hyporheic invertebrate communities differs significantly. Although pH, electrical conductivity and nitrate concentration differed in the surface water, variability of all chemical criteria studied in the hyporheic zones was much lower between the two streams compared to the variability within each stream. Thus the structure of both hyporheic invertebrate communities did not differ significantly. Because of this uniformity both streams are regarded to be suitable for a comparison in a whole-ecosystem experiment. 相似文献
969.
河口滨海湿地生态服务功能突出,生境脆弱易损,研究其生态脆弱性对滨海湿地生态环境保护与管理具有重要意义。本文以辽河口滨海湿地为例,基于“干扰-敏感-恢复”评估框架,选取17个指标,构建滨海湿地生态脆弱性评价指标体系,以GIS技术为支撑,综合运用插值法、综合指数法,探究辽河口滨海湿地生态脆弱性空间分布特征,分析生态脆弱性变化的影响因素。结果表明:入海河口污染、河口地区人类开发活动和自然淤涨对河口滨海湿地生态脆弱性的影响较为突出;2014年辽河口滨海湿地生态脆弱性总体态势良好,区域生态脆弱性指数为1.67,整体处于不脆弱状态;空间上,辽河口滨海湿地生态脆弱性表现为中部高于四周,由入海河口向外逐步减弱的格局特征。 相似文献
970.
We assessed spatial and temporal variability in the physical environment of a subarctic estuary, and examined concurrent patterns of chlorophyll α abundance (fluorescence), and zooplankton and forage fish community structure. Surveys were conducted in lower Cook Inlet, Alaska, during late July and early August from 1997 through 1999. Principle components analysis (PCA) revealed that spatial heterogeneity in the physical oceanographic environment of lower Cook Inlet could be modeled as three marine-estuarine gradients characterized by temperature, salinity, bottom depth, and turbidity. The gradients persisted from 1997 through 1999, and PCA explained 68% to 92% of the variance in physical oceanography for each gradient-year combination. Correlations between chlorophyll α abundance and distribution and the PCA axes were weak. Chlorophyll was reduced by turbidity, and low levels occurred in areas with high levels of suspended sediments. Detrended correspondence analysis (DCA) was used to order the sample sites based on species composition and to order the zooplankton and forage fish taxa based on similarities among sample sites for each gradient-year. Correlations between the structure of the physical environment (PCA axis 1) and zooplankton community structure (DCA axis 1) were strong (r = 0.43-0.86) in all years for the three marine-estuarine gradients, suggesting that zooplankton community composition was structured by the physical environment. The physical environment (PCA) and forage fish community structure (DCA) were weakly correlated in all years along Gradient 2, defined by halocline intensity and surface temperature and salinity, even though these physical variables were more important for defining zooplankton habitats. However, the physical environment (PCA) and forage fish community structure (DCA) were strongly correlated along the primary marine-estuarine gradient (#1) in 1997 (r = 0.87) and 1998 (r = 0.82). The correlation was poor (r = 0.32) in 1999, when fish community structure changed markedly in lower Cook Inlet. Capelin (Mallotus villosus), walleye pollock (Theragra chalcogramma), and arrowtooth flounder (Atheresthes stomias) were caught farther north than in previous years. Waters were significantly colder and more saline in 1999, a La Niña year, than in other years of the study. Interannual fluctuations in environmental conditions in lower Cook Inlet did not have substantial effects on zooplankton community structure, although abundance of individual taxa varied significantly. The abundance and distribution of chlorophyll α, zooplankton and forage fish were affected much more by spatial variability in physical oceanography than by interannual variability. Our examination of physical-biological linkages in lower Cook Inlet supports the concept of “bottom-up control,” i.e., that variability in the physical environment structures higher trophic-level communities by influencing their distribution and abundance across space. 相似文献