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61.
农村宅基地管理工作中,非法占地、非法转让土地、超面积占地、一户多宅、擅自改变宅基地用途和划新不丢旧等各种违法行为层出不穷,造成了农村宅基地管理混乱的局面。因此,必须加强宣传,做好规划、编制,完善相关法律、法规及执法监察等工作。  相似文献   
62.
北京十三陵地区中—新元古界碳酸盐岩Pb—Pb年龄研究   总被引:8,自引:0,他引:8  
对北京十三陵地区中一新元古界碳酸盐岩进行了系统地采样和207pb/204pb-206Pb/204Pb年龄测定.共测定了63个样品(大部分样品采取两种溶解方式),得到中元古界雾迷山组第三段的207Pb/204pb-206Pb/204pb等时线年龄为1373±92Ma(95%置信度误差,下同,MSWD=4.7),杨庄组为1488±55Ma(MSWD=14),高于庄组第三段为1608±74Ma(MSWD=8.1).这些年龄数据与目前已有地质记录相吻合.串岭沟组的碳酸盐相的206Pb/204Pb-207Pb/204Pb未构成等时线,但全岩的206Pb/204pb-207Pb/204Pb比碳酸盐相具有更明显的线性趋势,其原因尚待进一步研究.另外,根据同一个样品用稀盐酸溶解和用氢氟酸加硝酸混合酸溶解的铅同位素比值的接近的现象,显示碳酸盐岩中的硅质没有陆源的特征,是沉积盆地中的产物.  相似文献   
63.
昆明市东川区泥石流信息系统的建立及其应用   总被引:4,自引:2,他引:4  
根据东川区泥石流的成因、泥石流灾害信息源、各类数据的表达方式及泥石流信息系统的应用等,对东川区泥石流信息系统进行了系统分析,在此基础上利用3S技术,在ARCVIEW的AVENUE开发语言支持下,集成各类数据,建立东川区泥石流信息系统,最后讨论了该系统在泥石流危险度区划及灾害趋势分析中的应用。  相似文献   
64.
巴伦西亚水法庭是欧洲最古老的机构之一,其形式和内容一直延续至今,并对国际水法产生重要影响。针对我国越来越多的农村水事矛盾、水事纠纷事件,巴伦西亚水法庭处理水事纠纷的特点具有重要借鉴价值。研究表明:可以通过借鉴巴伦西亚水法庭重视农村水事纠纷特点的基础上处理好相邻关系;充分发挥民间调解在水事纠纷调处机制中的重要作用;增强用水自律意识;及时解决农村水事纠纷等措施,为充分发挥我国民间社团组织在处理农村水事纠纷的积极作用提供有益参考。  相似文献   
65.
Natural resource-dependent societies in developing countries are facing increased pressures linked to global climate change. While social-ecological systems evolve to accommodate variability, there is growing evidence that changes in drought, storm and flood extremes are increasing exposure of currently vulnerable populations. In many countries in Africa, these pressures are compounded by disruption to institutions and variability in livelihoods and income. The interactions of both rapid and slow onset livelihood disturbance contribute to enduring poverty and slow processes of rural livelihood renewal across a complex landscape. We explore cross-scale dynamics in coping and adaptation response, drawing on qualitative data from a case study in Mozambique. The research characterises the engagements across multiple institutional scales and the types of agents involved, providing insight into emergent conditions for adaptation to climate change in rural economies. The analysis explores local responses to climate shocks, food security and poverty reduction, through informal institutions, forms of livelihood diversification and collective land-use systems that allow reciprocity, flexibility and the ability to buffer shocks. However, the analysis shows that agricultural initiatives have helped to facilitate effective livelihood renewal, through the reorganisation of social institutions and opportunities for communication, innovation and micro-credit. Although there are challenges to mainstreaming adaptation at different scales, this research shows why it is critical to assess how policies can protect conditions for emergence of livelihood transformation.  相似文献   
66.
Distribution, abundance and life history characteristics of Mysis relicta were studied in the Feldberg Lake District (Lake Breiter Luzin, Lake Schmaler Luzin, Lake Zansen) located in northeastern Germany. Between July 2001 and November 2002 mysids were collected by vertical net hauls. In order to determine the impact of the current trophic conditions on the distribution of mysids in these lakes, oxygen concentration, total phosphorus, chlorophyll a and water transparency were also measured. All investigated lakes are mesotrophic at present. Lake Breiter Luzin exhibited great seasonal and spatial variations in mysid abundance. Density of adults and juveniles had a mean of 44.9 ± 57.1 and 68.7 ± 99.6 m−2, respectively. Highest abundance of adults was 110.4 ± 76.5 m−2 in summer, lowest abundances of 2.0 ± 4.0 m−2 occurred in spring. For juveniles, highest density of 218.4 ± 174.6 m−2 was detected in summer and lowest of 0.8 ± 1.8 m−2 in winter. No mysids were caught in any of the daytime hauls, but they were widely distributed throughout the water column at night. Size frequency distribution of mysids suggested that reproduction occurred year-round, the most consistent influx of juveniles occurred in early summer and a smaller second cohort in autumn. Highest mysid abundance was 189.2 ± 318.6 adults and 127.0 ± 66.3 juveniles m−2 in Lake Schmaler Luzin, and 59.6 ± 5.6 adults and 79.4 ± 11.2 juveniles m−2 in Lake Zansen. There were great spatial differences in abundance in both lakes.  相似文献   
67.
Family farms have long generated income from agricultural tourism including U‐picks, wagon rides, corn mazes and petting zoos, but contemporary agricultural tourism reflects much greater sophistication in terms of product variety, services, activities, and marketing. In Michigan, farm operators have moved beyond classic products and activities and the traditional consumer base. New sources of revenue derive from classes on beer, cider, mead and wine making, yarn spinning, perfume/soap‐making, farm markets, fishing, educational classes, school tours and hospitality including weddings and on‐farm restaurants. This case study of Michigan agricultural tourism reports results from a systematic survey of 154 agritourism operations conducted throughout the state during summer and fall of 2013 with a focus on the economic benefits of the fast‐changing sector. This study summarizes tax revenues, sales and employment trends for the farm operations participating in the survey but also quantitatively assesses the contribution of agricultural tourism to Michigan's economy through an extrapolation of the sample to estimate state‐wide totals. Results from OLS multivariate regression analysis intended to identify relationships between employment, advertising and scale to gross sales per day are also reported. These analyses show the importance of agricultural tourism to rural and peri‐urban places in Michigan and throughout the nation, while raising concerns about a growing division between large and small operators and what this growing gap may mean for the future of the sector.  相似文献   
68.
In this paper, the relationships between paleo-precipitation and the regional influence of El Nino Southern Oscillation (ENSO) in South America are assessed from a high-resolution calendar varve-thickness record. Two short laminated sediment cores (53 and 61 cm length) from Lago Puyehue (40° S) are analysed by continuous varve measurements through the last 600 years. The calendar varve years are determined by the occurrence of graded planktonic-rich layers. The annual sediment accumulation rates are reconstructed by using the standard varve-counting methods on thin sections. The 1980–2000 varve-thickness record is interpreted in terms of climate through correlation with limnological and local monthly instrumental climate databases. The comparison between the standardized varve thickness with the instrumental records reveals a strong correlation (r = 0.75, р = 0.07) between the total varve thickness and the austral autumn/winter precipitation. We argue that strong austral winter winds and precipitation are the forcing factors for the seasonal turn-over and phytoplankton increase in the lake sediments. During strong El Nino events the precipitation and the winds decrease abnormally, hence reducing the thickness of the biogenic sediments deposited after the winter turn-over. Our results show one significant regional maximum peak of winter precipitation (>900 mm) in the mid 20th century and a significant period with lower winter precipitation (<400 mm) before the 15th century, i.e., the late Medieval Warm Period. The first peak in the mid 20th century is confirmed by the regional precipitation database. The influence of ENSO cycles over the last 600 years is assessed by spectral analysis in Fagel et al. (2007). The possible influence of the regional volcanism and/or the seismic activity on the local climate record is also discussed. This is the sixth in a series of eight papers published in this special issue dedicated to the 17,900 year multi-proxy lacustrine record of Lago Puyehue, Chilean Lake District. The papers in this special issue were collected by M. De Batist, N. Fagel, M. -F. Loutre and E. Chapron.  相似文献   
69.
Transition to low carbon sea transport is a logical response to the extreme dependency of the Pacific Islands region on imported fossil fuel, its significant vulnerability to the effects of climate change and the critical shipping needs of Pacific Island countries (PICs). Building on previous work in low carbon sea transport in the Pacific, this paper further considers the barriers to achieving such transition by assessing, through a ‘post-Paris Agreement’ lens, the Intended Nationally Determined Contributions (INDCs) submitted by PICs and contrasting these to the near total lack of investment and planning for low carbon transition in the transport sector with the parallel occurrence in the electricity sector where ~USD 2 billion of donor investment is deployed or queued despite electricity using only ~20% of fossil fuel across the region. Consistent with recent international studies, inadequate and inappropriate financing and policy have been identified as dominant transition barriers for low carbon sea transport development in PICs. This paper further examines the regional level barriers to policy development, and finds them inhibited by the silo nature of the major regional actors. The implications that the Paris Agreement has for climate financing to support the essential research and capacity development needed to underpin a successful low carbon sea transport transition strategy at any useful scale and speed are also considered in this paper.  相似文献   
70.
广州南沙区地面沉降已经影响到城市发展和人民生命财产安全,为了制定科学有效的措施防止地面沉降进一步发展,文中基于InSAR监测数据和水准监测数据,总结分析了地面沉降分布特征,地表形变多为小范围的、局部地区的剧烈沉降。在此基础上,针对6个沉降严重区域,采用机理模型定量估算了各因素引起的地面沉降量及所占比重,得可压缩土层引起的沉降量为34.43~96.97 mm/a,所占比重在37.07%~75.67%,地下水水位和地面荷载的最大影响比重分别为26.28%和52.40%。并且通过研究分析地面沉降主要因素及影响程度,为科学防治该地区地面沉降提供科学依据。  相似文献   
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