广西生态旅游的现状、问题和对策

生态旅游是我国也是广西正兴起的一种旅游活动,它鲜明的特点决定了它在旅游业中的重要地位,然而在开发中存在诸多问题。需采取相应对策：增强旅游意识,建立法规、条例,先规划后开发,合理控制旅游活动量,加强管理力度,注重信息、掌握动态和适度开发,才能使广西的生态旅游有序快速发展     

“价值营销”——价值运筹的关键一环

在“价值运筹”的内涵中 ,“价值营销”顺理成章地取代了传统的营销概念。价值营销的精粹是 :让消费者获得令他满意的价值。为消费者提供满意的价值 ,是公司、企业赖以生存和长远发展的根本。为使消费者获得满意的价值 ,企业公司必须奉献“三心” :买得称心、用得舒心、长期放心。     

乡村振兴背景下村域尺度国土空间规划：认知、职能与构建

研究目的:在乡村振兴背景下,以国土空间规划体系重构为契机,科学认知村域尺度国土空间规划内涵,明确其基本职能,并提出构建路径。研究方法:文献研究法,综合分析法。研究结果:当前乡村面临转型,而村域规划存在理论认知不深入、技术支撑不足、实施管理困难等问题,新时期村域国土空间规划应依据外部社会背景及村庄内在条件,在全面认知乡村价值前提下,通过空间资源要素配置与用途管制来干预乡村空间重构并服务于乡村治理。研究结论:乡村振兴背景下村域国土空间规划应当具备指明乡村振兴路径、强化乡村空间治理、行使自然资源监管、尊重多元价值诉求等基本职能,并基于问题、需求、目标、行动四维导向进行构建。     

Incorporating risk in a positive mathematical programming framework: a dual approach

In this study we develop a new methodological proposal to incorporate risk into a farm‐level positive mathematical programming (PMP) model. We estimate simultaneously the farm nonlinear cost function and a farmer‐specific coefficient of absolute risk aversion as well as the resource shadow prices. The model is applied to a sample of representative arable crop farms from the Emilia‐Romagna region in Italy. The estimation results confirm the calibration ability of the model and reveal the values of the individual risk aversion coefficients. We use the model to simulate different scenarios of crop price volatility, in order to explore the potential risk management role of an agri‐environmental scheme.     

How well do conservation auctions perform in achieving landscape‐level outcomes? A comparison of auction formats and bid selection criteria

This paper studies the performance of auction design features regarding pricing mechanisms and bid selection criteria for securing wildlife zones across different holdings. We compare two pricing mechanisms: a discriminatory‐price auction and a uniform‐price ascending auction, and four bid selection criteria on the basis of: total bid, bid‐per‐value ratio, bid‐per‐area ratio and a mixed criterion where bids are formed on the basis of cost but they are selected based on the bid‐per‐value ratio. We develop a best‐response group‐bidding model for a discriminatory‐price auction where bidders form optimal group bids for individual wildlife zones. In the uniform‐price ascending auction, individual landholders respond to prices, which are successively raised by the auctioneer and whenever all the landholders from a single zone agree to participate (i.e. the first zone is formed), the auction stops. Based on numerical simulations using a bio‐economic model of malleefowl conservation, we observe that the discriminatory‐price auction is more cost‐effective than the uniform‐price ascending auction. However, the budgetary cost‐effectiveness of a discriminatory‐price auction is sensitive to bidder uncertainty about the number of competing bidder groups and the highest cost of establishing a wildlife zone among these groups. In terms of bid selection, the mixed bid selection criterion performs best. We discuss the policy implications of these findings.     

Reduction in nitrogen fertilizer use results in increased rice yields and improved environmental protection

Overuse of nitrogen fertilizer represents a considerable environmental problem globally, but especially in China. Recently, a recent approach on an experimental scale based on the diffusion of the so-called Three-Control Technology (TCT) successfully alleviated the overuse of nitrogen fertilizer in southern China villages in the Guangdong Province, serving as a reference point for other rice-producing countries tackling similar challenges. Here, we assessed the correlation between rice yields and reduction in the use of nitrogen fertilizer following the introduction of TCT. Our study was based on the collection of primary data from 248 households randomly selected from four rice-growing areas of Guangdong Province, China. Our results show that TCT significantly improved the efficiency in the use of nitrogen. Crucially, participating farmers, including both full adopters and partial adopters, were found to fundamentally change their application practices of nitrogen fertilizer, resulting in major improvements in the local soil and water systems.     

Ecosystem impacts of pesticide reductions through Bt cotton adoption

This article examines the ecosystem impacts of transgenic Bt cotton technology resulting from reduced chemical pesticide use. Employing unique panel data from smallholder farmers in India, negative environmental and health effects of pesticide use are quantified with the environmental impact quotient (EIQ), with and without Bt technology. An environmentally sensitive dynamic production function is estimated, treating the environmental risk of pesticide toxicity as an undesirable output in the production process. Negative externalities are significantly lower in Bt than in conventional cotton. The reduction in EIQ through Bt technology adoption has increased from 39 per cent during 2002–2004 to 68 per cent during 2006–2008. Bt adoption has also contributed to higher environmental efficiency. Environmental efficiency is influenced by the quality of Bt technology: high‐quality Bt seeds are associated with higher environmental efficiency than lower‐quality seeds.     

Effects of scale economies and production seasonality on optimal hub locations: the case of regional fresh produce aggregation

Interest in supporting local and regional food systems is rising and food hubs have attracted considerable attention among Federal, State, and local policymakers. This study explores the problem of endogenous hub location in fresh produce value chains in the Northeastern United States. To overcome limitations in the literature, we incorporate the effects of economies of scale and production seasonality into our models. Three experimental models are designed to examine the effects of alternatively applying yearly, quarterly, and monthly data on model solutions. We explicitly assess how interactions of scale economies and seasonality influence the structure and spatial attributes of an optimal regional produce aggregation hub system. The three models generate marketed different solutions and in many respects they lead to different conclusions about developing local/regional supply chains. The monthly model allows for production seasonality and actual hub operation cycle frequency and thus leads to more efficient hub solution with rich policy implications.     

重塑自然资源管理新格局：目标定位、价值导向与战略选择

研究目的:立足新时代党和国家机构改革背景,分析自然资源管理改革目标定位和面临挑战,明确未来自然资源管理改革价值导向与战略选择。研究方法:文献研究法,综合分析法。研究结果:自然资源管理改革的目标定位是实现"五统一",即统一调查评价、统一确权登记、统一"多规合一"和用途管制、统一资产管理和统一督查监管。针对当前自然资源管理理论储备不足、开发利用伦理缺乏科学引导、开发和保护矛盾冲突长期存在、新管理体制效能有待实践检验等挑战,自然资源管理改革亟需注重"公平效率"、强调"永续利用"、融合"三资一体"、构建"有效市场",切实重塑自然资源管理新格局。研究结论:新时代自然资源管理改革应该以权籍为基础,完善自然资源市场体系;以规划为龙头,构建国土空间规划体系;以"三线"为底线,推进全域国土空间用途管制;以整治为抓手,推进"山水林田湖草"生命共同体综合治理;以法制为保障,构建自然资源管理法律体系,从而塑造"三体系一管制一治理"的自然资源管理新格局。     

Erosion mitigation in the Waikato District,New Zealand: economic implications for agriculture

Soil erosion, in its various forms, is caused or aggravated by agricultural activities. Mitigation of surface erosion comprises the construction of shelterbelts, fencing, riparian buffering, and stock reduction. Mitigation of mass‐movement erosion, in turn, takes the form of spaced planting of trees to maintain a persistent, healthy, and complete ground cover. In this article, we assess the economic implications to agriculture of the adoption of mitigation alternatives for erosion control in the Waikato District, New Zealand. The Waikato District presents a spatial pattern of erosion that affects profitability of dairy, and sheep and beef enterprises. We use the Universal Soil Loss Equation and the New Zealand Empirical Erosion Model to estimate erosion figures that are then fed into an economic‐focused, nonlinear, partial equilibrium mathematical programming model of New Zealand land use. Different scenarios are constructed for surface and mass‐movement soil erosion targets ranging from 0% to 50% below baseline levels. We find that achieving surface erosion targets is more expensive than mass‐movement targets, and results in different responses in regional‐level costs, land use, enterprise net revenue, and adoption of mitigation alternatives.