生态景观质量的游客感知及支付意愿评价——以福友休闲农场为例

在近年来国内休闲农业快速发展的背景下,由于缺乏对其非使用价值的正确认识和判断,出现了高速增长与效果欠佳的矛盾,如何科学评价休闲农场开发的非使用价值,对于该产业发展具有重要意义。条件价值评估方法(CVM)是国内外评估非使用价值和支付意愿较为成熟的方法,但尚未用于对具有"三产融合"和"三生一体"特性的休闲农场的评估,本研究以福建开发较为成熟的长泰福友休闲农场为研究取样点,采用该方法探究游客对休闲农场生态景观质量的感知水平及支付意愿。结果表明:游客对福友休闲农场生态保护价值支付意愿的下限为18.26元,支付上限为23.10元,游客对福友休闲农场生态景观保护的支付意愿为96.45万元/年;提供便捷的支付渠道和公开资金的使用途径能有效提升游客购买生态景观保护价值的支付意愿;农场空气的好坏、农场的生态体验设计、农场的田园功能分区在主题设计、耕作体验形式、内容等方面的创新程度对游客生态保护的支付意愿影响较大;对于大部分拥有一定农场阅历但对农业多功能性认识不足的游客,在便捷的支付手段和珍稀植物品种的吸引下,更倾向于形成较低水平的生态保护价值支付意愿,而那些文化素质较高,特别是拥有农场、生态相关领域研究背景,对于农场生态功能性、体验养生内容拥有一定认知的游客,则愿意在更高的价格水平支付农场的生态保护价值。     

Per-capita estimations of long-term historical land use and the consequences for global change research

Changes in land use and land cover are important in global climate change, but the many uncertainties in historical estimates seriously hamper climate modelling. We collected new data on estimated per capita land use over the last two millennia, using new data sources from the Humanities. In general, and in agreement with literature, we found that per capita land use indeed has not been constant in the past, but differ per region and over time. Land use in the distant past was mostly less than 1 ha/cap. However, the recently colonised regions show much higher values and have experienced a much higher per capita land use for the recent past. Most known trajectories follow a concave or bell-shaped curve towards the present.     

Linking Soil Erosion to Instream Dissolved Phosphorus Cycling and Periphyton Growth

Phosphorus (P) is a limiting nutrient in freshwater systems and when present in runoff from agricultural lands or urban centers may contribute to excessive periphyton growth. In this study, we examined the link between soil erosion and delivery of eroded soil to streams during flow events, and the impact of that freshly deposited soil on dissolved reactive P (DRP) concentrations and periphyton growth under baseflow conditions when the risk of stream eutrophication is greatest. A microcosm experiment was designed to simulate the release of P from soil which had been amended with different amounts of P fertilizer to overlying water during baseflow conditions. Unglazed tiles, inoculated for five days in a second order stream, were incubated for seven days in microcosms containing soil with eight levels of soil Mehlich‐3 plant available phosphorus (M3P) ranging from 20 to 679 mg/kg M3P. Microcosm DRP was monitored. Following incubation tiles were scraped and the periphyton analyzed for chlorophyll a. Microcosm DRP concentrations increased with increasing soil M3P and equilibrium phosphorus concentration (EPC₀). Relationships between M3P, EPC₀, and DRP were nonlinear and increases in soil M3P and/or DRP had a greater impact on biomass accumulation when these parameters were above threshold values of 30 mg/kg M3P and 0.125 mg/L DRP. Significantly, this ecological threshold corresponds to the agronomic thresholds above which increased soil M3P does not increase plant response.     

Assessing agricultural vulnerability to climate change in the Nordic countries – an interactive geovisualization approach

Nordic agriculture must adapt to climate change to reduce vulnerability and exploit potential opportunities. Integrated assessments can identify and quantify vulnerability in order to recognize these adaptation needs. This study presents a geographic visualization approach to support the interactive assessment of agricultural vulnerability to climate change. We have identified requirements for increased transparency and reflexivity in vulnerability assessments, arguing that these can be met by geographic visualization. A conceptual framework to support the integration of geographic visualization for vulnerability assessments has been designed and applied for the development of AgroExplore, an interactive tool for assessing agricultural vulnerability to climate change in Sweden. To open up the black box of composite vulnerability indices, AgroExplore enables the user to select, weight, and classify relevant indicators into sub-indices of exposure, sensitivity, and adaptive capacity. This enables the exploration of underlying indicators and factors determining vulnerability in Nordic agriculture.     

泥石流滩地农业资源化开发与利用——以蒋家沟为例

泥石流滩地是山区宝贵的土地资源,其农业资源化开发与利用对促进当地社会经济发展和生态环境改善具有重要意义。以蒋家沟流域为例,在野外调查、遥感解译和实验分析的基础上,阐述了泥石流滩地农业资源化的原则和依据,建立了人畜 土地载荷平衡模型,分析了滩地开发利用的依据、效益和途径,并探讨了泥石流滩地未来农业资源化的思路和对策。研究结果表明：（1） 建立的人畜 土地载荷平衡模型反映了流域生态环境特征,能有效评价滩地开发利用的生态效益;（2）流域滩地农业资源化每年可产生500多万元的经济效益,除满足全流域6 418人的粮食需求外,还可提供338 t商品粮,是促进当地脱贫致富和社会经济发展的重要途径;（3）泥石流滩地既是宝贵的土地资源又是灾害的场所,其开发与利用可有效缓解山区人地矛盾,具有良好的生态效益,但需要在加强灾害防治和防灾减灾意识的基础上,进行深度农业资源化开发.     

Adoption of sustainable agriculture practices: Evidence from a semi-arid region of Ethiopia

In the wake of the resource constraints for external farm inputs faced by farmers in developing countries, sustainable agriculture practices that rely on renewable local or farm resources present desirable options for enhancing agriculture productivity. In this study, plot-level data from the semi-arid region of Ethiopia, Tigray are used to investigate the factors influencing farmers' decisions to adopt agriculture practices, with a particular focus on conservation tillage, compost and chemical fertilizer. A trivariate probit model is used to analyze the determinants of adoption of these practices. In addition, stochastic dominance analysis is used to compare the productivity impacts of compost with that of chemical fertilizer based on a six-year cross-sectional farm-level dataset. Our results indicate heterogeneity with regard to the factors that influence adoption decisions of the three practices and the importance of both plot and household characteristics on influencing adoption decisions. In particular, we found that household endowments and access to information, among other factors, impact the choice of sustainable farming practices significantly. Furthermore, the use of stochastic dominance analysis supported the contention that sustainable farming practices enhance productivity. They even proved to be superior to the use of chemical fertilizers — justifying the need to investigate factors that influence adoption of these practices and to use this knowledge to formulate policies that encourage adoption.     

The life cycle of rice: LCA of alternative agri-food chain management systems in Vercelli (Italy)

The Vercelli rice district in northern Italy plays a key role in the agri-food industry in a country which accounts for more than 50% of the EU rice production and exports roughly 70%. However, although wealth and jobs are created, the sector is said to be responsible for environmental impacts that are increasingly being perceived as topical. As a complex and comprehensive environmental evaluation is necessary to understand and manage the environmental impact of the agri-food chain, the Life Cycle Assessment (LCA) methodology has been applied to the rice production system: from the paddy field to the supermarket. The LCA has pointed out the magnitude of impact per kg of delivered white milled rice: a CO_2eq emission of 2.9 kg, a primary energy consumption of 17.8 MJ and the use of 4.9 m³ of water for irrigation purposes. Improvement scenarios have been analysed considering alternative rice farming and food processing methods, such as organic and upland farming, as well as parboiling. The research has shown that organic and upland farming have the potential to decrease the impact per unit of cultivated area. However, due to the lower grain yields, the environmental benefits per kg of the final products are greatly reduced in the case of upland rice production and almost cancelled for organic rice. LCA has proved to be an effective tool for understanding the eco-profile of Italian rice and should be used for transparent and credible communication between suppliers and their customers.     

关于农业生态旅游的几点看法

农业生态旅游已逐渐成为普通大众的一种新的旅游消费方式,近年来国内外正在不断兴起。农业生态旅游是农业生产与旅游活动的有机结合,它已日益成为农业的一个新的经济增长点。发展农业生态旅游需要加强旅游地的“软件”(生态旅游规划、广告策划等)和“硬件”(基础配套设施等)的建设,特别是健康优美的农村生态环境的建设与保护,要本着大农业、大生态、大旅游的思想,推动农业生态旅游的产业化进程及其可持续发展。     

论生态示范区建设与生态农业产业化

从实践和理论两个方面探讨了生态示范区建设中生态农业的地位、生态农业产业化的定义、内涵、技术对策及发展方向     

华北平原土壤肥力的变化与影响因素分析

通过对２０世纪以来华北平原土壤调查数据的分析对比,揭示了从传统农业向现代农业转变的过程中土壤肥力的变化。从总体上看,冀北地区的土壤肥力有所下降,而冀南和鲁西北地区有所上升。影响肥力变化的因子包括河流治理、施肥、高产品种使用后种植制度和土地利用程度的变化等等。