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1.
在西藏,家庭曾是老年人养老的基本依赖。然而,随着经济社会条件的变化和人口流动,老年人的生存状况与过去大不相同。传统的家庭养老功能面临着新的挑战,主要表现如家庭结构逐渐趋向小型化、子女数量减少而使家庭供养负担加重、老龄化导致家庭养老功能弱化。面对这些新的挑战,西藏城乡居民的养老出现新趋向,如自我养老观念提高、女儿养老地位加强以及社会化养老等。  相似文献   
2.
Models of cities based on conventional spatial market theory are unable to replicate a realistic size distribution. The stochastic process approach to size distribution, which assumes proportionate growth, does not provide an economic foundation for spatial trades. There is an apparent irreconcilability. We propose that since there is a continuum of equilibria in models of spatial markets with endogenous location, proportionate growth can work as equilibrium selection. We present computations for an urban configuration that has not been presented in the literature before. A small city locates inside a larger city's agricultural supply zone. This generates a larger variation in city size that may include a realistic size distribution.  相似文献   
3.
The current challenge for world agriculture is to provide food for a growing population, within a context of environmental degradation and economic inequality. The challenge is how to produce accessible, healthy, diverse, nutritious, safe and abundant food in a way that is sustainable, allowing farmers to exert food sovereignty while at the same time addressing ecosystem conservation. The aim of this study is to explore the potential contribution of traditional agriculture to food sovereignty and also to understand the challenges that indigenous communities are facing today. Our case studies are from six Latin-American countries: Chile, Peru, Ecuador, Colombia, Guatemala and Mexico, where we carried out semi-structured, guided visits and field observations. Our results shed light on how traditional agricultural knowledge, techniques and practices can contribute to these issues, but also to the need of protecting and recovering the cultural and ecological heritage. There is a need to resolve public management issues, related to development investment, technological packages, cultural loss and gender. If these are not addressed, the potential contribution of ancient agricultural knowledge will fail to contribute to strengthen food sovereignty and maintain the local markets, which are also places for seed exchange, knowledge sharing and social networking.  相似文献   
4.
The evidence on yields, food-production, food-calories per capita, and declining levels of malnutrition in countries experiencing a Green Revolution are commonly cited in support of the claim that the GR sought to maximise food production. If one looks closely at the actual design of GR programmes (in India and elsewhere), however, it is clear that they were instead intended to boost yields and profitability in a small number of targeted areas. The underlying rationale for targeting was that achieving very high yields in such regions would persuade farmers to abandon subsistence farming in favour of commercial production, relying upon the market for the purchase of inputs as well as the sale of produce. In response to widespread criticism of the Green Revolution ca. 1970 for neglecting the needs of peasant farmers (as well as accentuating rural unrest), the World Bank and other donors began to direct more attention and resources to smallholders, but the aim of commercialising farming remained unchanged.  相似文献   
5.
Abstract

The purpose of this study is to analyse the new processes of tourism growth and its conflicts from the perspective of social movements. First, the urban growth machine analysis model is applied by the systematisation of six projects. Second, the resistance movements against those projects and whether this resistance could be the start of local tourism degrowth policies are examined. The methodology is qualitative, based on documentary analysis, participatory observation, discussion groups and interviews. The case study is the destination of Costa del Sol-Málaga. The results enable the development of the urban growth machine model in tourist destinations. Meanwhile, social movements demystify the argument based on neoclassical economic progress. The social movements condemn the effects of large-scale top-down projects, and implement alternative bottom-up proposals. Although the social movements do not reject tourism, they call for greater control over its impact, denounce unlimited growth, overtourism and the loss of urban quality of life. These movements advocate a lifestyle linked to the everyday space, which they believe is threatened by excessive urban-tourism growth. They are a symptom of the need to devise a proposal using the principles of degrowth.  相似文献   
6.
[目的]与我国的农业资源禀赋条件相似,荷兰人多地少,农业资源贫乏,却是世界农业强国,其20世纪80年代开始的农业转型之路对促进我国当前农业绿色发展具有重要借鉴意义。[方法]结合实地调研与文献研究,文章梳理了荷兰40年来在农业环境治理方面的具体政策设计和实施效果,并分析了其主要经验做法及对我国发展的启示。[结果]从畜禽养殖数量控制到化学投入品控制、再到农业资源全管理,荷兰始终坚持以种养结合的可持续发展模式应对农业资源环境挑战,不断强化循环利用技术推广应用,逐步建立了严格的农业资源环境监管体系和政府支持体系,在农业污染得到有效治理的同时,依然很好地保持了国际市场竞争力。[结论]荷兰曾经面对的养殖业污染、化学品过度投入等问题也是我国当前农业环境的突出问题,其当时采取的转型思路与我们目前的绿色发展理念高度一致,借鉴荷兰经验,加快推进我国农业绿色发展,亟需创新循环农业发展模式,加强绿色发展技术支撑,建立并完善农业绿色发展制度体系,协同推进农业资源环境保护和农业竞争力提升。  相似文献   
7.
Conservation Agriculture (CA) is advocated as an agricultural innovation that will improve smallholder famer resilience to future climate change. Under the conditions presented by the El Niño event of 2015/16, the implementation of CA was examined in southern Malawi at household, district and national institutional levels. Agricultural system constraints experienced by farming households are identified, and in response the technologies, structures and agency associated with CA are evaluated. The most significant constraints were linked to household health, with associated labour and monetary impacts, in addition to the availability of external inputs of fertiliser and improved seed varieties. Our findings show that such constraints are not adequately addressed through current agricultural system support structures, with the institutions surrounding CA (in both Government extension services and NGO agricultural projects) focusing attention predominantly at field level practice, rather than on broader system constraints such as education and health support systems. Limited capacity within local institutions undermines long term efforts to implement new technologies such as CA. It is vitally important that the flexibility of farmers to adapt new technologies in a locally-appropriate manner is not closed down through national and institutional aims to build consensus around narrow technical definitions of a climate-smart technology such as CA. To enable farmers to fully utilise CA programmes, interventions must take a more holistic, cross-sectoral approach, understanding and adapting to address locally experienced constraints. Building capacity within households to adopt new agricultural practices is critical, and integrating healthcare support into agricultural policy is a vital step towards increasing smallholder resilience to future climate change.  相似文献   
8.
城市自生群落具有重要的生态服务功能与潜力,但因其外貌不被公众所接受而难以在城市公共空间中应用。将群落生态学和设计学相结合,探索一种介入栽培植物对城市自生群落进行改良,最终形成具有一定美学价值的植物群落的途径。实验以植物群落设计美学原理和种间竞争原理为依据,向已经演替1年的城市自生群落中引入63种栽培植物,按照分层的方式对群落进行改良。3年的观测结果表明,有61.9%的栽培植物可以在城市自生群落中定居并建立优势,能对76.7%的自生植物起到抑制作用,使55.8%的自生植物消失。相比城市自生群落,改良后的群落美观度提高29.4%,公众接受度提高24%,群落的物种丰富度提高至2.29倍。相比一般的人工植物群落,改良后的群落可以节约58.2%的建植成本,降低83.9%的浇水成本和67.8%的除草成本。实验证明改良设计是一种可行的群落设计途径,能有效提高群落的物种丰富度和美学价值,同时让自然参与群落设计过程,实现人与自然的合作。  相似文献   
9.
研究目的:本文将政府间竞争划分为财政竞争和引资竞争,比较两者对城市土地市场化水平影响的大小,分析政府间竞争与城市土地市场化水平之间的关系。研究方法:基于2003—2016年全国284个地级市的面板数据,利用双边随机前沿模型测算财政竞争和引资竞争对城市土地市场化水平的影响。研究结果:财政竞争对城市土地市场化水平具有正向效应,提高了城市土地市场化水平1.61%;引资竞争对城市土地市场化水平具有负向效应,降低了城市土地市场化水平12.51%;政府间竞争总体上降低了城市土地市场化水平10.90%。时间趋势表明,政府间竞争对城市土地市场化水平的抑制作用呈现波动下降的状态。研究结论:政府间竞争降低了城市土地市场化水平。  相似文献   
10.
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