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101.
旅游业已经成为中国城乡发展的新动力,在城乡地域功能演化中起到的作用越来越显著。山地丘陵地区在旅游业驱动下,多种地域功能交互重叠,构成了多类型复杂耦合空间,面临着区域可持续发展的模式抉择。本研究以河南鲁山县为例,探讨山地丘陵地区在旅游引导下的城乡一体化发展策略。研究发现:(1)山地丘陵地区的地域功能正在从传统单一的“居住-农业非农业生产”向综合功能的“生态保障-居住-农业非农业生产-休闲文化服务”转变,多类型空间交互特征明显。(2)鲁山县由农业经济主导向旅游经济主导转变,可划分为旅游服务承接平台区、山地生态旅游发展区、特色林业旅游融合区、平原高效农旅融合区,进行中心城区-中心镇-一般镇-中心村的层级划分和产业方向优化。(3)发展策略应强调分层实施、分类引导,优化城乡利用空间,做好城乡地域分类引导,实现资源要素合理配置。研究成果为认识山地丘陵地区地域功能演化规律、制定城乡一体化发展策略提供了科学案例。  相似文献   
102.
浙江省南部山区生态系统服务价值评估   总被引:1,自引:0,他引:1  
选择浙江省南部山区泰顺县作为研究区域,对全县各类生态系统服务价值进行了定量评估,并在此基础上进行了生态系统服务重要性及其区域分异规律的综合评价。结果表明:2012年全县生态系统服务总价值为334.1×108元,是当年该县GDP的6.40倍,其中以水源涵养、气候调节、土壤保持服务价值为主,三者分别占总价值的62.35%、21.8%、7.16%,生态系统有着巨大的间接服务价值。生态系统服务重要性分析结果显示,极重要、很重要、重要区、一般重要区域分别占全县总面积的31.43%、34.57%、20.35%、13.64%,评估结果可为生态系统的科学管理、生态保护关键区的确定以及生态保护和建设政策的制订提供理论依据。  相似文献   
103.
We examine factors affecting the adoption of improved cassava varieties of 217 households in the Cauca Department in southwest Colombia. Using DNA fingerprinting through Single Nucleotide Polymorphisms (SNPs), we identified different cultivars in farmers fields. We also used this information to remove possible bias in the adoption model that could have resulted from a misclassification of improved varieties (IVs). As a result, we found that farmers substantially overestimate their use of IVs and there are important differences in the determinants of adoption between farmer self‐identification and DNA fingerprinting. This finding implies that the incorporation of DNA fingerprinting in IV adoption studies is important to ensure the accuracy of future agricultural economic research and the relevance of subsequent policy recommendations.  相似文献   
104.
In Sub-Saharan Africa, fish ponds are often an integral part of farming systems but have suffered from a lack of viability and sustainability. The present study aims to understand the strategies used by fish farmers to overcome economic and environmental constraints. In 2008 and 2009, fish farmers were surveyed in Central and Western Cameroon, and the fish production systems were classified by cluster analysis. Four broad types were identified according to the complexity of household operations. The development of extensive systems (large-scale and low-input) in rural areas of central Cameroon is induced mainly by abundant available land. For semi-intensive systems in both regions (small-scale and high-input in the Western Region, large-scale and high-input in peri-urban areas of the Central Region), horizontal integration is not sufficient to make fish production profitable and sustainable. More intensive fish farms tend towards vertical integration, in which farmers establish close links with input suppliers. Main causes of low productivity of semi-intensive systems (1–2?t/ha/yr) are both lack of knowledge of fish farming principles by farmers and lack of technical improvement by extension agents and researchers which need to consider the local complexity of farming systems to develop and intensify fish production. The adaptation of development strategies to socio-economic and environmental contexts is a necessity to hope for an increase in fish pond aquaculture production in Africa.  相似文献   
105.
This article revisits a conventional wisdom that inorganic fertiliser use across sub‐Saharan Africa is too low. This expectation that more farmers should be using inorganic fertiliser, and at higher rates, implies it is profitable to use rates higher than observed if farmers are rational expected profit maximisers. We obtain consistent estimates of the effects of applied nitrogen on rice production. We find the yield response to applied nitrogen to be low in the main rice growing farming system. Farmer behaviour is not inconsistent with expected profitability which is limited by a low yield response to applied fertiliser, high transportation costs, and low selling prices for rice in rural areas. In particular, we do not find any farmers for whom applied nitrogen is profitable that are not using fertiliser in the study sample for each of our survey years (2010 and 2012).  相似文献   
106.
Achieving the Sustainable Development Goals (SDGs) in African agriculture requires a better understanding why high levels of poverty and resource degradation persist in African agriculture despite decades of policy interventions and development projects. In this article, we hypothesize that policies need to account for the key features of the semi‐subsistence crop–livestock systems (CLS) in the region to become effective. The semi‐subsistence CLS are characterized by a high degree of biophysical and economic heterogeneity and a complex, diversified production system involving a combination of subsistence and cash crops with livestock. We investigated the potential for interventions proposed by the Government of Kenya to meet the SDGs by 2030. The analysis uses an integrated modeling approach designed to deal with the key features of these systems. A strategy that stimulates rural development, increases farm size to a sustainable level, and reduces distortions and inefficiencies in input and output markets could lead to a sustainable development pathway and achieve the SDGs for rural households dependent on CLS.  相似文献   
107.
This study attempted to gain insights on Brazilian consumers’ subjective knowledge of sodium content in processed and homemade foods and their purchase intent for products with reduced‐sodium content. A questionnaire was distributed to 409 consumers selected by convenience quota sampling. We found that Brazilian consumers were concerned about the amount of salt (sodium chloride) in the products they consumed, regardless of educational levels, income, age, lifestyles, or health conditions. However, they still considered their consumption to be above WHO‐recommended limits and had little subjective knowledge about the term ‘sodium’. While processed products were considered the main contributors of high‐sodium intake, participants were not concerned about addition of salt at the table and salt in homemade food. The majority of respondents rarely read the sodium content on food labels; however, men and older individuals were more likely to read label information on sodium content. Products with reduced sodium were found to have market appeal, which justifies investments in research to develop these products. Therefore, in addition to the efforts to reduce sodium in the processed‐food industry, it is necessary to promote awareness about the importance of food labelling, especially sodium content, and the need to reduce salt in homemade food and additions during meals.  相似文献   
108.
This study examines both accruals based earnings management (AEM) and real earnings management (REM) in U.S. agribusinesses. In particular, the focus is on agribusinesses that report low earnings quality, defined as firms with extreme level of accruals compared to their peers. The cross‐sectional modified Jones model (Jones 1991; Dechow et al 1995) is used to test for AEM. To capture REM practices, we implement the discretionary expenses model by Roychowdhury (2006). We find evidence of AEM and find no evidence of REM in agribusinesses. In addition, our results show that managers might be managing earnings through specific accruals doubtful accounts receivable provisions and special items.  相似文献   
109.
Colin I. Bradford and William H. Branson (eds). Trade and Structural Change in Pacific Asia Jimmy M. Wheeler and Perry L. Wood, Beyond Recrimination: Perspectives on US-Taiwan Trade Tensions Bruce Dickson and Harry Harding (eds), Economic Relations in the Asian-Pacific Region  相似文献   
110.
In 2015, the Federal Communications Commission (FCC) imposed common carriage regulation—so-called Title II requirements—on previously unregulated broadband Internet service providers. The regime shift was premised on the FCC’s findings that such rules had demonstrably yielded economic gains. This paper evaluates the FCC’s empirical arguments and finds them uncompelling. Adjustments for inflation or general economic trends eliminate the effects cited by the FCC. Moreover, contrary to the Commission’s assessment, mobile services and broadband markets have shown notable growth in response to deregulatory events that reduce Title II requirements.  相似文献   
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