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1.
Continuity and change: Spatiotemporal land use dynamics on Bellona Island, Solomon Islands 总被引：2，自引：2，他引：0
Torben Birch-Thomsen Anette Reenberg Ole Mertz Bjarne Fog 《Singapore journal of tropical geography》2010,31(1):27-40
Traditional agricultural land use systems in the humid tropics of the Southwest Pacific are, as elsewhere, affected by globalization processes. This paper analyzes the directions of change in the land use system of Bellona, a small outer island in the Solomon Islands. We focus on the human–environmental interaction that shapes land use patterns and practices in the context of theoretical lines of thought concerning intensification of agricultural systems in the tropics. Aerial photography from 1966 and satellite imagery from 2006 in conjunction with studies from the 1960s and a contemporary household survey reveal only minor changes in the agricultural system. Land use and land cover dynamics are related to agricultural strategies, demographic factors, institutional actors as well as biophysical drivers or constraints. Local agricultural production still contributes significantly to local subsistence but imported food has also become a major food source. Hence, land use has become partially disconnected from the local population pressure and therefore remains relatively stable while the larger livelihood portfolio has undergone significant diversification. At present, the agricultural system is a supplement to a range of strategies supporting the increasing number of people on the island. This explains why land use patterns continue relatively unchanged while livelihood and food supply strategies have changed. 相似文献
2.
利用可比净出口指数、贸易集中度指数、Hilbert曲线、时空多元模式可视化、岭回归等方法,对1992—2020年中国农产品贸易结构演化进行分析,并解释其与粮食安全的关系。结论认为：① 1992—2020年中国农产品贸易总体格局发生了转变,表现为对国际进口的依赖显著增强,猪肉、牛肉、玉米、高粱、油菜籽等众多农产品由出口转变为进口状态。快速增长的进口直接增加了国内食物的供应,提升了粮食安全水平。② 农产品进口呈现产品结构和空间结构双集中的叠加效应,这种效应使得重点农产品进口极易受美国、澳大利亚等少数国家贸易政策变化的不利影响;在出口方面,农产品集中度较小,随着与“一带一路”等地区国家贸易的发展,地理集中度也显著降低。较低的集中度有利于稳定出口的经济效益,保障出口部门农业生产的稳定性。③ 中国农业生产出现部分进口产品生产规模压缩的趋势,加上高度集中的进口结构,将使得国内农业生产与粮食安全保障在面对外部冲击时更加脆弱。建议在坚持贸易开放的同时,优化农产品的生产和贸易结构,引导形成合理的农业种植格局。 相似文献
3.
Maize diversity is important to the livelihoods of millions of farmers in Mexico, the crop's centre of origin; to maize breeders seeking new genetic material; and to producers and consumers worldwide. Key social processes that determine maize diversity include historic and cultural emphases on maize as a primary crop; land-use practices encompassing heterogeneous agro-ecological conditions; farmers' seed-saving practices; farmer selection of useful traits; and farmer seed exchange and purchasing networks. We consider the impacts of recent agricultural and rural development policies on these processes. We focus on La Frailesca, a commercial and semi-subsistence maize-growing region in southern Mexico. Qualitative data were collected via focus group discussions, semi-structured interviews, and participant observation in four villages at intervals over a 2-year period. These techniques were complemented with semi-structured interviews with local and state policymakers. Observations suggest that policies promoting market liberalisation, agricultural modernisation, and rural education have contributed to significant changes in the social processes which have historically generated maize diversity. Increasing numbers of smallholder maize producers are diversifying into alternative livelihood options, including temporary or permanent migration, and cultural and economic emphases on maize production are changing. Changes in La Frailesca raise important questions about the fate of maize genetic diversity as the Mexican agricultural sector is further realigned with the global agricultural economy. 相似文献
4.
Brazil is the largest economy in Latin America and the world's leading producer and exporter of coffee. Smallholders are the predominant producers of Brazilian coffee and have been significantly impacted by post-ISI (import substitution industrialisation) neoliberal reforms that swept the nation's agricultural sector beginning in the 1980s. These reforms stimulated increased coffee production while simultaneously diminishing state interventions, including agricultural subsidies, farmer credits, research and development programmes, extension services, and rural development initiatives. These changes were closely followed by major restructuring of the global coffee market and the elimination of international coffee export quotas. Our research joins a growing body of recent literature exploring how changes related to market liberalisation and globalisation affect localities and regions where producers supply coffee for conventional markets. Through a case study, we describe the impacts of neoliberal globalisation on the lives, livelihoods, and environment of small-scale coffee producers in Minas Gerais, Brazil. We explore how neoliberal reform, reflected in the specific historical, geographical, and environmental context of Brazilian coffee production, has resulted in the increased marginalisation of small-scale farmers, the degradation of soils, and overall rural decline. 相似文献
5.
Duncan F.M. McGregor Andrew Adam‐Bradford Donald A. Thompson David Simon 《Singapore journal of tropical geography》2011,32(3):382-398
This paper outlines pressures on agricultural land in periurban Kumasi, Ghana. A survey of agricultural practices underlines the recent and rapid transition from agricultural to urban land use in the periurban interface, and shows how farmers are reacting by reducing fallow periods. Farmers are also intensifying agriculture near streams and rivers through increased use of irrigation, in response to growing urban markets for a wider range of vegetables. We identify specific problems of water resource pollution and waste management, with particular reference to farmland irrigation. We report results of composting interventions as a community‐based waste management strategy. We consider integrated organic waste recycling as a generic strategy to help protect periurban natural resources, to enhance food production through nutrient recycling, and to improve community sanitation. 相似文献
6.
Even though cities cover approximately only 3 per cent of the earth's land area, they are often located on what previously was prime agricultural land. In line with what was common historically, many cities around the world are now deliberately seeking to promote and expand agricultural production within their borders. Pressure for change is coming from a number of sources, including both governments and private citizens. Potentially, community gardens and domestic backyard food production have an important role to play in this process, but while there now exists a sizeable body of research on the former, there is a serious lack of data on current productive practices in private domestic gardens. While other researchers have asked householders to estimate garden production, we believe this to be the first project to carefully document measured output by multiple households. The paper presents the results of a fine-grained study of 15 selected householders in metropolitan Melbourne. Participants collected detailed daily information about their food production over a three-month period. In addition, two of the respondents had been keeping daily production records continuously for one or more years. The results demonstrate enormous diversity in the food harvested, as well as some extremely high levels of productivity from relatively small domestic spaces. Participants were also questioned about their motivations for engaging in backyard food production and dealing with surpluses. 相似文献
7.
干旱绿洲农业区村庄多功能特征与类型划分研究——以临泽县为例 总被引：1，自引：0，他引：1
村庄是最能直接体现乡村经济社会活动规律的单元,落实到村级层面的功能类型划分是分类推进乡村振兴的关键。以行政村为基本单元,采用熵权法、泰尔指数及优势功能模型,构建适用于村庄发展功能识别与类型划分的研究思路,并以西北干旱绿洲农业区临泽县为例进行实证研究。结果表明：干旱绿洲农业区总体形成以农产品生产和生态保育为主的国土空间格局,村庄形成农业种植、畜牧养殖、工业加工、商贸旅游、劳务输出、生活保障等多功能地域综合体,其中农产品生产和生活保障功能总体空间差异较小,而非农生产功能空间差异较大。村庄因资源禀赋、规划引导、政策驱动和社会需求差异形成不同的优势功能类型,空间上呈现“外围生态、沿河种植、中部农牧、临城劳务,文旅、商旅、生活保障以政府驻地及附近村庄为主”的分布规律,并形成非农生产功能镶嵌于农业生产功能之中、生产生活功能被生态保育功能包围的分布格局。通过自上而下主体功能统筹与自下而上经济社会需求相结合的方法进行村庄发展功能识别和类型划分具有较强的适用性和实践指导价值,在巩固国家主体功能定位、保障国家粮食和生态安全的同时,可以调整优化县域资源要素配置,实现村庄发展功能互补与功能协调。 相似文献
8.
河南省小麦生产的区域差异及其对农用地分等的影响 总被引：3，自引：0，他引：3
河南是农业大省，粮食产量居全国首位，但全省粮食产量区域差异比较明显，豫东平原、豫北山前平原、南阳盆地为主要产粮区，而西部山区粮食生产力低下。农用地质量的优劣直接决定着粮食产量的高低，而作物的生产潜力和现实生产力影响着农用地质量的好坏。一般来说，作物生产潜力空间分布具有明显的南北纬度地带渐变规律，现实生产力则是在土地的自然属性融入社会经济因素而导致的土地投入和利用上的差异。文章以小麦为例，主要从潜在生产力和现实生产力2个方面阐述了造成小麦产量区域差异的原因并分析了它们对农用地分等产生的影响。 相似文献
9.
China’s low agricultural labor productivity has become the key weakness of its agricultural competitiveness and sustainable development, and strategies for improving China’s agricultural labor productivity lack clear and consistent theory and empirical support. To address this issue, the current study uses the methods of convergence index, correlation coefficient, and nonparametric test, to analyze the characteristics and influencing factors of agricultural labor productivity among 32 major agrarian countries during 1961-2013. This analysis shows that the development gap among countries has been narrowing. The USA takes the leading position among all the countries, while some countries with scarce land like Japan have succeeded in achieving transcendence, and other countries like India have experienced relatively slow speed. The agricultural labor productivity is significantly driven by agricultural labor surplus, agricultural product processing, and agricultural industrial structure. The effects of land resource endowment, agricultural mechanization, and biochemical inputs have been declining and in some cases are no longer even significant. It is therefore necessary to shift attention to marketization, diversification, and high quality, instead of the former focus on agricultural intensification, concentration and large-scale operations, and this shift is probably more closely aligned with current practices. There are more people and less land in China, and the agricultural labor force in China still accounts for nearly 30% of the total population. Considering these national conditions, it is very important to simultaneously improve the efficiency of agricultural production of small farmers and promote the successful urbanization of the agricultural labor force. In the medium and long term, it is imperative to improve the competitiveness of Chinese agriculture by adopting related policy arrangements such as induced agricultural technological innovation, production factor substitution, and multifunctional agriculture development. 相似文献
10.
WILLIAM G MOSELEY 《The Geographical journal》2005,171(1):36-55
This study examines the hypothesis that poor households engage in less sustainable soil management practices than rich households in a similar socioeconomic environment. This broad objective is explored in Mali's southern cotton belt through three specific research questions. First, is there empirical evidence to support the claim that poor households engage in less sustainable soil management practices than rich households? Second, what local and extra-local factors influence household agricultural management approaches in southern Mali? Third, what broader scale political and economic processes are linked to the factors that influence local-level agricultural management approaches? The author reports that soil quality measures on the farms of rich and poor households are not significantly different, refuting the conventional wisdom that the wealthy are better managers of the environment. A variety of environmentally deleterious practices are associated with export-oriented cotton production, an activity more vigorously pursued by wealthy than poor farmers. Finally, the focus on poverty in international environment and development discourse has allowed the government of Mali to avoid a serious debate on the sustainability of cotton production. The study's findings are based on household interviews describing agricultural management practices, an analysis of farm field soil measures, and discussions with donors and national policymakers. 相似文献
11.
Sustainable land use in Tikopia: Food production and consumption in an isolated agricultural system 总被引：3，自引：3，他引：0
Ole Mertz Thilde Bech Bruun Bjarne Fog Kjeld Rasmussen Jytte Agergaard 《Singapore journal of tropical geography》2010,31(1):10-26
The land use system on Tikopia – a Polynesian outlier in Solomon Islands – is analyzed to determine how it has developed since it was first described in the 1930s and again in the 1970s. Fieldwork included a household questionnaire survey, in-depth interviews on farming practices and decision making, and the collection of soil samples from the major soil and garden types. The Tikopian land use system has not undergone significant changes since the 1970s; indeed the focus on self-sufficiency in food crops may have been strengthened over the past 30 years as ship arrivals have become increasingly unreliable. Local agricultural production and exploitation of marine resources are essential to sustain the population, and with few exceptions farming and fishing techniques remain unchanged. Most of the island is still farmed permanently and the intensive agricultural system has not suffered long-term setbacks, not even from extreme events such as Cyclone Zoe in 2002. The high fertility of Tikopian soils reported in the 1960s was found to be unchanged. It is concluded that the land use system is highly resilient to shocks and that there are no indications that Tikopian villagers would not be able to support their subsistence in the future, provided there is no substantial increase in the resident ( de facto ) population. 相似文献
12.
Impacts of climate change on winter wheat growth in Panzhuang Irrigation District, Shandong Province
Global climate change has significant impacts on agricultural production. Future climate change will bring important influences to the food security. The CERES-Wheat model was used to simulate the winter wheat growing process and production in Panzhuang Irrigation District (PID) during 2011–2040 under B2 climate scenario based on the Special Report on Emissions Scenarios (SRES) assumptions with the result of RCMs (Regional Climate Models) projections by PRECIS (Providing Regional Climates for Impacts Studies) system introduced to China from the Hadley Centre for Climate Prediction and Research. The CERES-Wheat model was calibrated and validated with independent field-measured growth data in 2002–2003 and 2007–2008 growing season under current climatic conditions at Yucheng Comprehensive Experimental Station (YCES), Chinese Academy of Sciences (CAS). The results show that a significant impact of climate change on crop growth and yield was noted in the PID study area. Average temperature at Yucheng Station rose by 0.86℃ for 1961–2008 in general. Under the B2 climate scenario, average temperature rose by 0.55℃ for 2011–2040 compared with the baseline period (1998–2008), which drastically shortened the growth period of winter-wheat. However, as the temperature keep increasing after 2030, the top-weight and yield of the winter wheat will turn to decrease. The simulated evapotranspiration shows an increasing trend, although it is not very significant, during 2011–2040. Water use efficiency will increase during 2011–2031, but decrease during 2031–2040. The results indicate that climate change enhances agricultural production in the short-term, whereas continuous increase in temperature limits crop production in the long-term. 相似文献
13.
基于EPIC模型的黄淮海夏玉米旱灾风险评价 总被引：10，自引：1，他引：9
玉米是中国最主要的粮食作物之一,因其较高的需水量,受气候影响,极易遭受旱灾。因此,以黄淮海夏播玉米区为例,从风险的角度进行玉米旱灾评价,对于农业旱灾预警和保障国家粮食安全具有重要的现实和指导意义。在全面收集研究区气象、土壤、土地利用、农气观测等资料的基础上,基于农业旱灾风险评价的概念框架“致灾因子危险性H评价(Hazard)-承灾体脆弱性曲线Vc 评价(Vulnerability Curve)-作物减产风险性R评价(Risk)”,引入基于物理过程的作物模型EPIC (Erosion Productivity Impact Calulator),采用作物模型模拟和数字制图等技术,分别从全生育期和分生育期角度,对黄淮海夏播玉米区玉米旱灾风险的时空分布进行了定量评价。结果表明：在2、5、10 和20 年一遇致灾水平下,黄淮海夏播玉米区玉米旱灾减产风险总体呈现出从西北向东南方向递减的趋势,这主要由气候环境和下垫面的地形地貌条件所决定。20 年一遇水平时,产量损失风险的高值区(R ≥ 0.5) 集中分布在冀北高原山地和山东省中南部地区,占黄淮海夏播玉米区玉米总面积的7.63%。黄淮海夏播玉米区成灾风险较高的生育期：拔节期-抽雄期、抽雄期-乳熟期、乳熟期-成熟期应加强防范。研究可为高风险区和高风险时段的玉米旱灾风险防范提供理论依据和科技支撑。 相似文献
14.
Paul Swagemakers Johannes S.C. Wiskerke 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(2):149-167
Geografisk Tidsskrift-Danish Journal of Geography 111(2):149–167, 2011 The modernization of agricultural food production has diminished and is diminishing the sustainable use of the local natural resource base, resulting in the fragmentation of landscapes and the decline of biodiversity. In this paper we analyze the revitalization of ecological capital, which provides insights into how effective adjustments in land-use and farming practices can stimulate a reconnection between farming, nature and society. The paper focuses on a case study about endogenous knowledge on the relation between farm activities and the reproduction of the landscape and its flora and fauna in the (Dutch) Friesian Woodlands. We suggest that building adequate, local institutional frameworks that strengthen landscape structures, regional identity and the ‘branding’ of food products will sustain rural development in the area. The results should be of value for increasing the understanding among researchers and policymakers of the potential of endogenous knowledge in governing the increase of the ecological stock in an area. 相似文献
15.
ABSTRACT. Farmers in Marin and Sonoma Counties, located north of San Francisco, are experimenting with numerous alternatives to California's widely known industrial dairy style. Many analysts suggest that consumer politics, food scares, and globalization explain such shifts to organic and other types of “quality” food production. While acknowledging the importance of these factors, we argue that the alternatives in this region are best understood as an outcome of broad‐based land‐conservation efforts developed through historical and ongoing struggles over urban growth, rising concerns about environmental values, and deep regional interests in dairy preservation. Over time, preservation of this agricultural landscape has contributed to the emergence of a quality food industry historically rooted in the region's politics of place. 相似文献
16.
Pimentel D 《社会与自然资源》1991,4(4):347-363
Destruction of forests and the considerable burning of fossil fuels is directly causing the level of carbon dioxide and other greenhouse gases including methane, carbon monoxide, and nitrous oxide in the atmosphere to rise. Population growth in the US and the world indirectly contributes to this global warming. This has led the majority of scientists interested in weather and climate to predict that the planet's temperature will increase from 1.5 to 4.5 degrees Celsius by 2050. These forecasted climactic changes will most likely strongly affect crop production. Specifically these scientists expect the potential changes in temperature, moisture, carbon dioxide, and pests to decrease food production in North America. The degree of changes hinges on each crop and its environmental needs. If farmers begin using improved agricultural technology, the fall in crop yields can be somewhat counterbalanced. Even without global warming, however, agriculture in North America must embrace sensible ecological resource management practices such as conserving soil, water, energy, and biological resources. These sustainable agricultural practices would serve agriculture, farmers, the environment, and society. Agriculturalists, farmers, and society are already interested in sustainable agriculture. Still scientists must conduct more research on the multiple effects of potential global climate change on many different crops under various environmental conditions and on new technologies that farmers might use in agricultural production. We must cut down our consumption of fossil fuel, reduce deforestation, erase poverty, and protect our soil, water, and biological resources. The most important action we need to take, however, is to check population growth. 相似文献
17.
我国食物安全研究进展及展望 总被引：5，自引：1，他引：4
保障我国食物安全是我国一切建设发展的前提和基础。在我国农业基础资源日益紧缺以及加入WTO 的 国情下, 食物安全面临着新的机遇与挑战。本文回顾了食物安全概念的演变过程, 综述了我国在自然基础资源与食 物安全、食物安全现状及其评价、国际贸易和经济全球化对食物安全的影响以及食物安全预警和管理等方面的研 究进展, 并对未来我国食物安全研究进行了展望。研究表明: 今后我国食物安全研究应在以下方面需要加强: 在研 究内容上, 不仅重视食物数量保障, 更应注重食物质量安全、食物资源可持续利用和综合食物安全风险评价与预警 等方面; 在研究视角上, 不仅重视宏观食物安全研究, 更应重视微观食物安全; 在研究方法和手段上, 应当充分运用 现代科学技术, 如网络技术、空间模拟技术以及3S 技术等, 进一步加强综合食物安全的定量和动态研究。 相似文献
18.
“土地分离和共享框架”是协调物质生产和生态保护、促进土地可持续利用的重要理论。本文梳理了“土地分离与共享框架”和生态系统服务间关联,剖析生态系统服务应用于该框架的理论基础,结合美国典型土地共享案例,分析了土地利用策略选择对粮食生产、生物多样性、直接和间接生态系统服务的影响,并探讨了该框架对中国生态系统工程的启示。结果表明：随着人类对土地功能认知的不断深入,“土地分离与共享框架”的拓展表现为从单一的粮食供给服务需求演进到粮食供给服务和其他生态系统服务的综合需求。当粮食供给服务与其他服务处于权衡状态时,在生态脆弱、恢复力差的地区,不同生态系统服务间多处于凸权衡关系,一般适宜采用分离策略;在生态系统稳定、恢复力强的地区,不同生态系统服务多处于凹权衡关系,一般适宜采用共享策略。结合美国典型土地共享案例发现,其土地利用实践中选择土地功能共享策略是比较适宜的;生态系统服务作为政策评估工具,可在策略选择和评估实施效果中发挥一定作用。研究结果可为可持续土地利用提供理论与方法支撑,并为中国制定土地利用策略提供参考。 相似文献
19.
Clinton Beckford David Barker Steve Bailey 《Singapore journal of tropical geography》2007,28(3):273-286
Small-scale farmers' experimental innovations have not generally been considered for on-farm research trials as those in the traditional sector have been perceived as recipients, rather than originators, of technical knowledge and sustainable and viable practices. Yet there is abundant evidence throughout the tropics that small-scale farmers are adaptive and experimental problem solvers, and experts at devising innovative survival strategies. While literature on the topic is rich with accounts from Africa, Asia and Latin America, there is a general dearth of examples from the Caribbean. This paper highlights some examples of farm- and village-level problem solving and survival practices among small-scale domestic food producers in the challenging agroecological environment of Jamaica. 相似文献
20.
吉林省西部沙化土地持续农业体系建立的实践 总被引：2，自引：1，他引：2
吉林省沙化土地的８７．９％分布在吉林省西部白城、松原半干旱地区，统属科尔沁和松嫩沙地，面积９２１６．５ｋｍ２，占吉林省西部总面积的１９．６％。８年（１９８６年～１９９３年）实践证明：针对沙地环境特点建立的“乔、灌、草”、“果、药、杂”、“田、林、草”为主体的三种持续农业体系效果明显。 相似文献