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1.
张旭 《农业考古》2020,(1):7-15
本文对内蒙古中南部先秦两汉时期11组古代人群的龋病状况做了统计与分析,在与我国北方地区16组古代人骨材料对比的基础上,进一步讨论了其生业模式与龋患的关系。龋病的罹患情况是反映人群摄入碳水化合物含量的有效指标,龋病与人类社会生产力发展以及农业出现相关,内蒙古中南部地区先秦两汉时期不同生业模式人群的碳水化合物食物摄取量的多寡决定了其龋齿发病率的高低,以农业经济为主的人群龋齿发病率最高,并随着时代发展而进一步增加;以畜牧或渔猎采集经济为生的古代人群龋病发病率较低;农牧兼营的混合经济人群龋齿发病率居中,并且因农业经济所占比重的不同,其变异范围较大。  相似文献   
2.
We investigated the effects of various anthropogenic factors on urban soil properties in subtropical, coastal Tampa, FL, USA. Specifically, we explored the influence of (i) urbanization as measured by land use, land cover, population density and years since urban development and (ii) socioeconomic conditions as reflected in household income and property values on bulk density (BD) and several key soil chemical properties. Results indicate that Tampa’s urban soils were affected to varying degrees by these factors with chemical properties being more variable than BD. Across land uses significant differences were found for Mehlich‐1 (M1) extractable P, Ca and Na. A similar trend was observed for land‐cover classes, although significant differences were also found for pH and M1‐Cu. Soil properties had no statistically significant relationship with population density. However, time since urbanization did with M1‐P and Na varying significantly across age categories. For our socioeconomic analyses, M1‐K and Mg levels differed significantly by household income while pH, P, Ca and Na values differed significantly by property value. Overall, our findings indicate that despite their inherent heterogeneity, there are identifiable patterns among subtropical coastal urban soil properties. We suggest that a more thorough understanding of these patterns and their drivers is an essential first step towards developing soil management strategies aimed at maintaining environmental quality and ecosystem services in subtropical cities.  相似文献   
3.
Agroforestry systems (AFS) have received much attention from policymakers and others for their perceived ability to contribute significantly to economic growth, poverty alleviation, and environmental sustainability. Yet in many areas of the developing world where AFS have proven their agronomic potential, they have yet to be widely adopted. This paper approaches the issue with a focus on one such area – the western Brazilian Amazon, an area where economic integration within the region itself, across national boundaries, and between the region and the rest of Brazil (’regional integration‘) may soon vastly shift incentives to natural resource users. The paper addresses AFS adoption via a conceptual framework that argues for scrutinizing agronomic and socioeconomic characteristics of AFS and their potential adopters. This framework facilitates a priori assessment of whether specific AFS will be adopted, and if so, by whom and with what likely impact on the development objectives at hand. It highlights characteristics that lend socioeconomic and agronomic ’agility‘ – connoting flexibility to easily shift production systems and accompanying marketing strategies in response to unforeseen or rapid change (due to qualities of the AFS itself, or the producer). Financial performance indicators (net present value of AFS during establishment and for the life of a project, and years to positive cash flow) are presented for selected AFS, and juxtaposed to a livestock production system that is already gaining wide adoption in the area. This juxtaposition illustrates the practical effects of socio-economic and agronomic characteristics posited as influential. Against this backdrop, trends in ’regional integration' are discussed, along with implications this integration process has for AFS adoption. The paper ends with a discussion of the roles and limitations of policy in promoting AFS adoption. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
4.
Smallholder perceptions of agroforestry projects in Panama   总被引:7,自引:1,他引:7  
The potential effects of agroforestry systems on conservation and development have been well documented. Panama has seen a substantial rise in the number of projects with an agroforestry component in the 1990s. There has been insufficient research on the actual impacts of these projects on smallholders and of farmers' attitudes towards these systems. This study explores the perceived socioeconomic and environmental impacts of five agroforestry projects in Panama. A total of 68 smallholders were administered semi-structured interviews. In addition, 13 agroforestry experts from NGOs, government departments and research institutes were interviewed, and their responses were compared with those of the smallholders. While the projects led to an increase in the standard of living by providing wood products and fruit for domestic consumption, farm income levels generally remained unchanged. This was due primarily to limited market development, the lack of marketing organizations and poor access roads. In terms of environmental impacts, the farmers' responses suggested a slight decline in slash-and-burn agriculture, and an increase in tree planting activities. Some environmental benefits were observed by farmers, including reduced soil erosion, increased soil fertility, and improved quality and quantity of water sources. Nevertheless, slash-and-burn agriculture was still the norm for the majority of farmers. Most farmers continued to harvest wood from primary and secondary growth to meet their domestic wood requirements, rather than relying on trees planted in agroforestry projects. The main obstacles preventing increased agroforestry adoption included insufficient agroforestry extension, inappropriate project design or management (such as top-down management approaches, and the use of food incentives), smallholders' economic constraints, and larger policy issues. Recommendations are proposed to improve project design and management, and to address the economic and policy constraints. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
5.
[目的] 从地形和社会经济两个因素出发探讨广东省土地覆被变化的时空差异及成因,为土地资源的可持续利用提供依据。[方法] 基于1992-2015年间广东省土地覆被数据,使用土地利用动态度、土地利用转移矩阵、灰色关联分析等方法量化土地覆被变化的时空特征与差异。[结果] 广东省土地覆被变化以2000年为节点可分为前期(1992-2000年)和后期(2000-2015年)两个阶段。前期耕地面积显著增加,建筑用地面积增速缓慢;后期耕地面积减小,建筑用地面积扩张迅速。地形因素造成土地覆被变化存在空间差异性。在高程低,坡度缓的区域土地覆被变化主要是耕地转化为建筑用地,而在坡度中等区域主要是林地转为耕地。社会经济因素造成土地覆被变化呈现较明显时间差异性,多种因子驱动广东省土地覆被发生变化。但对于不同的土地覆被类型,驱动因子前后期的关联度大小不同,土地覆被发生变化是多种因子驱动叠加的结果。[结论] 地形因素会造成土地覆被变化的空间差异,而社会经济因素导致土地覆被变化的时间差异。  相似文献   
6.
粉领阶层的出现是中国经济与社会变迁的产物。木文考察了现代中国城市中粉领女性的生活状态、阶层地位与自我认同,认为粉领阶层处于社会结构的中间阶层,其阶层认同正处于建构发展之中,其性别角色观念则介于现代与传统之间。  相似文献   
7.
从“六五”开始,中国政府在全国300多个县开展“农村能源综合建设县项目”,根据能源、经济、环境协调发展和资源合理配置的总目标,通过综合规划,选择建设项目,制定总体方案和技术路线,因地制宜地开发当地资源,高效利用和节约商品能源,发展可再生能源产业。由此不仅全面系统地解决农村地区的能源问题,而且取得了可观的经济、生态和社会效益。根据该项目的实施特点,着重讨论如何对这一综合项目进行社会经济效益及可推广性评价方法研究,提出了评价方法框架,供有关决策部门和研究单位参考。  相似文献   
8.
基于山西省太原市45个居住区绿地植物多样性调查,运用植物多样性指数及PCA主成分分析,分析居住区绿地植物多样性特征及其与社会经济因子之间的关系。结果表明,太原市居住区绿地中维管束植物146种,隶属于39科、73属,其中乔木101种,灌木45种。53%的居住区绿地中的乔木物种数为11~20种,而51%的居住区绿地中的灌木物种数为5种及以下,乔木物种的丰富度和均匀度均明显高于灌木物种。PCA排序结果显示,城镇居民人均可支配收入、城镇居民人均消费性支出及房龄是影响植物多样性水平的主要因子。  相似文献   
9.
水土保持功能评价及其在水土保持区划中的应用   总被引:3,自引:0,他引:3  
随着国家对生态文明建设的日益重视,以及国家及地方主体功能区规划的实施,对于水土保持的功能研究也越来越多.结合全国水土保持规划工作的需要,提出水土保持功能的概念、类型确定原则和功能类型,阐述了水土保持基础功能和社会经济功能的评价方法,以及各基础功能的评价指标体系.以太行山东部山地丘陵区为例,举例说明水土保持功能评价的过程和结果.对全国水土保持区划三级区基础功能进行统计分析,明确各功能的区域比例,提出8个一级区水土保持工作主要方向,维护和提高区域水土保持功能将成为水土保持工作的重点和方向.  相似文献   
10.
首先探析了保护区与周边社区的相互作用及其组成的特殊复合生态社会经济系统。其次, 阐述了现行保护政策下, 保护区周边社区的传统及现实权益未被考虑, 社区与保护区被人为割裂, 保护政策与地方发展政策不一致, 导致保护区与社区之间冲突不断, 使得保护目标难以达成。最后, 提出保护区管理者应关注社区合理权益的实现, 吸引社区群众参与自然保护工作, 同时寻求地方发展政策与保护政策的融合, 以促使保护区得到更好的建设和发展。  相似文献   
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