Rain forest dwellers' livelihoods: income generation,household wealth and NTFP sales,a case study from Xishuangbanna,SW China

Through annual in-depth household questionnaire interviews of 60% of households in Daka and Baka villages from 1998 to 2004, we explored wealth-related differences and similarities in the sale of NTFPs of tropical rain forest fringe dwellers in Xishuangbanna, SW China. Contribution of different NTFPs to cash income and different seasonal access to NTFPs between Baka and Daka were analysed. There were significant differences in income and role of NTFPs per household between Baka and Daka related to different access to: NTFPs in forests, labour and market sales in different seasons. In Baka, the ranking of NTFP income was: fungi, wild vegetables, bamboo shoot in 2000 and 2001. Differences in gender and generational involvement in NTFP sales was also examined. For example, households without a son, as well as those with a female householder depended more on income from NTFPs and less on income from rubber than other households. Resource use patterns between relatively wealthy and poor households were also analysed. Wealthy households sold 2.50 ± 0.50 types while poor households sold 2.08 ± 0.26 NTFPs. The Gini coefficient of gross income per household for Baka in recent years was 0.393, increasing to 0.414 without NTFPs. The Gini coefficient of gross income for Daka in recent years was 0.291, increasing to 0.292 without NTFPs, showing the different role of NTFPs in mitigating wealth inequality in the two villages.     

江苏和吉林农村家庭能源消费差异及影响因素分析

通过对江苏省和吉林省农村能源消费的实地调查,分析了农村家庭能源消费的区域差异.结果表明,由于冬季取暖需求,吉林省农村人均总能源消费量高于江苏;在生物质能源方面,江苏使用秸秆居多,而森林资源丰富的吉林以秸秆和薪柴并重;在商品能源消费方面,江苏人均消费电力、成品油、液化气多于吉林,而煤炭消耗少于吉林;在新型可再生能源--沼气消费方面,江苏的推广效果好于吉林.运用经济计量模型分析了农村家庭能源消费的影响因素,结果表明:人均纯收入、人均耕地面积、人均耐用家电价值、人均摩托车及生产性固定资产价值、地区等因素是影响农村家庭人均能源消费量的重要因素;同时,政府的资金技术支持、人均纯收入、人均生猪养殖数量、农户位于粮食主产区或林区等因素对农户选择使用沼气有重要影响.     

我国农村能源政策以及收入水平对农户生活能源需求的影响研究

针对传统能源使用过程中产生的环境、气候问题,由中央政府制定并实施的农村能源政策倡导农户使用多种清洁能源及技术。同时,商品能源逐步成为当下农户生活能源的重要组成部分。“并举式”的能源政策是否造成甚至扩大不同能源、技术的需求差异,这一结果是否符合政策的初衷和目标?基于此,论文研究并分析2005—2014年农村能源政策以及收入水平对农户生活能源需求的影响。结果表明：政策的实施加剧了存在替代关系的能源、技术需求间的此消彼长;政策的溢出效应促进了部分商品能源需求;收入的提高对部分能源需求产生了正向作用。建议制定兼顾清洁能源以及商品能源的农村能源发展战略和政策,实现政策的精准发力,同时加强能源基础设施的建设和管理。     

基于农户微观视角下的大城市郊区耕地土壤质量变化驱动机制研究

对耕地土壤质量变化驱动机制的研究是破解耕地质量变化规律及其效应的关键。利用野外采样与实验室分析相结合、统计分析和计量经济模型等分析方法,对研究区域238 个耕地地块的土壤采样数据和对应农户调查数据进行实证研究,结果表明,不同区域农户土地利用方式、程度和投入强度对耕地土壤质量的作用方向、影响程度和显著水平都不同。其中近郊区的农户“以兼业为主,以农为辅”,其行为突出表现为劳动力投入的“非农化”趋势,对耕地的粗放利用和掠夺式经营现象比较普遍,主要影响因素土地利用程度每增加一个单位,导致耕地土壤的碱解氮、速效磷和速效钾的含量平均下降11.496、44.078 和15.469 mg/kg;研究区域中部农户“以兼业为主”,突出表现为集约化程度比近郊区农户有所提高、种植结构也不断调整,对土地的投入、管理都得到很大的提高,主要影响因素土地利用方式转变会促使土壤有机质、碱解氮、速效磷和速效钾含量平均提高4.799 g/kg、7.454 mg/kg、100.170 mg/kg 和61.205 mg/kg;远郊区的农户“以农为主”,突出表现为“非粮化”趋势,由于比较高的就业机会成本,种地收入超过农户预期,耕地集约化、规模化程度较高,主要影响因素土地投入强度每增加一单位,土壤碱解氮、速效磷和速效钾含量平均增加0.007、0.025 和0.037 mg/kg。基于以上的研究结果,从提高农业生产比较效益、稳定农村土地承包关系和促进土地适度规模经营等方面提出规范农户土地利用行为,改善区域耕地土壤质量的政策建议。     

Home composting as an alternative treatment option for organic household waste in Denmark: An environmental assessment using life cycle assessment-modelling

An environmental assessment of the management of organic household waste (OHW) was performed from a life cycle perspective by means of the waste-life cycle assessment (LCA) model EASEWASTE. The focus was on home composting of OHW in Denmark and six different home composting units (with different input and different mixing frequencies) were modelled. In addition, incineration and landfilling was modelled as alternatives to home composting. The most important processes contributing to the environmental impact of home composting were identified as greenhouse gas (GHG) emissions (load) and the avoided emissions in relation to the substitution of fertiliser and peat when compost was used in hobby gardening (saving). The replacement of fertiliser and peat was also identified as one of the most sensible parameters, which could potentially have a significant environmental benefit. Many of the impact categories (especially human toxicity via water (HTw) and soil (HTs)) were affected by the heavy metal contents of the incoming OHW. The concentrations of heavy metals in the compost were below the threshold values for compost used on land and were thus not considered to constitute a problem. The GHG emissions were, on the other hand, dependent on the management of the composting units. The frequently mixed composting units had the highest GHG emissions. The environmental profiles of the home composting scenarios were in the order of −2 to 16 milli person equivalents (mPE) Mg⁻¹ wet waste (ww) for the non-toxic categories and −0.9 to 28 mPE Mg⁻¹ ww for the toxic categories. Home composting performed better than or as good as incineration and landfilling in several of the potential impact categories. One exception was the global warming (GW) category, in which incineration performed better due to the substitution of heat and electricity based on fossil fuels.     

近55年来华东地区旱涝时空变化特征

基于华东地区89个气象站点近55年逐月降水资料,运用趋势分析法、IDW空间插值法、标准化降水指数(SPI)等方法,分析了1960~2014年期间我国华东地区旱涝灾害时空变化特征,并探讨了淮河南北旱涝的时空差异。结果表明:(1)近55年华东地区降水量整体呈波动上升趋势,其中淮河以北地区降水量呈波动下降趋势,而淮河以南呈上升趋势。(2)从年尺度旱涝变化看,华东地区雨涝频率大于干旱频率,但干旱强度大于雨涝强度,且淮河以南地区的干旱强度大于淮河以北,而雨涝强度小于淮河以北。(3)华东地区南北旱涝站次比呈反向发展趋势,即淮河以北旱灾影响范围不断扩大,雨涝影响范围不断减小,淮河以南与之相反。(4)华东地区严重旱涝频率在空间分布上呈南北反向格局,即淮河以北旱灾频率高,涝灾频率低;淮河以南涝灾频率高,旱灾频率低。     

欠发达地区农户生产效率研究——以西藏自治区为例

以西藏自治区为例,在2009年农户抽样调查数据基础上,利用数据包络法(DEA)探讨西藏不同区域农户生产效率,认为西藏农户生产效率差异与农业生产中自用价值的计算有关,若考虑自用价值,在固定生产规模报酬(CRS)假设下,平均生产效率为0.653,其中拉萨市最高(0.784),日喀则市最低(0.277);若不计入自用价值,山南与那曲地区呈现最高生产效率。表明西藏农户收入中自用价值占了较大比例,扣除自用价值,收入大幅减少,影响生产效率。因此,提高农牧户生产商品率是增加农牧民收入的有效途径。     

LCA of local strategies for energy recovery from waste in England, applied to a large municipal flow

An intense waste management (WM) planning activity is currently undergoing in England to build the infrastructure necessary to treat residual wastes, increase recycling levels and the recovery of energy from waste. From the analyses of local WM strategic and planning documents we have identified the emerging of three different energy recovery strategies: established combustion of residual waste; pre-treatment of residual waste and energy recovery from Solid Recovered Fuel in a dedicated plant, usually assumed to be a gasifier; pre-treatment of residual waste and reliance on the market to accept the ‘fuel from waste’ so produced. Each energy recovery strategy will result in a different solution in terms of the technology selected; moreover, on the basis of the favoured solution, the total number, scale and location of thermal treatment plants built in England will dramatically change. To support the evaluation and comparison of these three WM strategy in terms of global environmental impacts, energy recovery possibilities and performance with respect to changing ‘fuel from waste’ market conditions, the LCA comparison of eight alternative WM scenarios for a real case study dealing with a large flow of municipal wastes was performed with the modelling tool WRATE. The large flow of waste modelled allowed to formulate and assess realistic alternative WM scenarios and to design infrastructural systems which are likely to correspond to those submitted for approval to the local authorities. The results show that all alternative scenarios contribute to saving abiotic resources and reducing global warming potential. Particularly relevant to the current English debate, the performance of a scenario was shown to depend not from the thermal treatment technology but from a combination of parameters, among which most relevant are the efficiency of energy recovery processes (both electricity and heat) and the calorific value of residual waste and pre-treated material. The contribution and relative importance of recycling and treatment/recovery processes change with the impact category. The lack of reprocessing plants in the area of the case study has shown the relevance of transport distances for recyclate material in reducing the efficiency of a WM system. Highly relevant to the current English WM infrastructural debate, these results for the first time highlight the risk of a significant reduction in the energy that could be recovered by local WM strategies relying only on the market to dispose of the ‘fuel from waste’ in a non dedicated plant in the case that the SRF had to be sent to landfill for lack of treatment capacity.     

分布式认知理论框架下农户土地转出意愿影响因素研究——基于SEM模型的武汉城市圈典型地区实证分析

基于分布式认知理论,从"个人力"、"地域力"、"文化力"三个层次构建农户土地流转认知的影响因素理论框架,利用"武汉城市圈"典型地区土地流转调查数据构建结构方程模型(Structural Equation Model,SEM),定量分析各影响因素在农户土地流转认知中的作用。研究证实:不同农户认知群体之间存在不同流转认知偏好,"无文化的老农民"相对于"有文化的年轻职业者"在土地流转认知中更加保守;农户对土地的需求普遍偏向土地的资产属性和财产权利,农村土地流转具备内在动力;然而,出于对土地社会保障功能的需求,农户不会因为其家庭生产方式和经济来源明显脱离土地而产生强烈的土地转出愿意,农户的家庭生计条件及"土地情节"在一定程度上制约了土地流转;村镇干部"取信于民"是农户获得"安全感",克服风险规避心理促进土地流转认知的最重要因素;流转价格是对农户在土地流转中物质与精神"双重损失"的资金补偿,两者的匹配程度对农户的认知具有重要作用。在此基础上,得出要规范流转程序、健全流转监督机制、保护农民利益,加强农村社会保障制度建设以确保农民获得公平的社会保障,加快推进和支持农村教育以提高农村劳动力素质,建立和完善土地流转制度保障和农业经营扶持机制等政策启示。     

基于城镇化的居民生活能源消费碳排放门限效应分析

正确认识城镇化发展中碳减排的阶段性特征和应对我国城镇化进程中的碳排放挑战,具有重要的理论参考价值和现实指导意义。现有研究较少关注城镇化发展对居民生活能源消费碳排放的影响,未能将城镇化自身阶段性变化对生活碳排放的影响联系起来。基于此,本文以城镇化率作为门限变量,以生活能源结构、居民消费率、产业结构分别作为解释变量,构建多个不同视角的门限-STIRPAT扩展模型,深入分析城镇化水平处于不同阶段时,居民生活能源消费碳排放所受影响的差异性。研究表明,城市化率分别处于门限值(0.250、0.325和0.457)前后时,居民生活能源消费碳排放所受影响出现了阶段性的变化。当城镇化率低于0.250时,能源结构、居民消费率和产业结构对居民生活能源消费碳排放均呈负向弹性关系,分别为-0.688、-0.570、-0.570;当城市化率低于0.457时,能源结构、居民消费率和产业结构对居民生活能源消费碳排放的负向弹性关系仍然存在,但相关关系明显减弱,能源结构负向弹性关系介于(-0.338,-0.019),居民消费率和产业结构负向弹性关系为-0.251。当城市化率超过0.457时,能源结构、居民消费率和产业结构对居民生活能源消费碳排放已逐步显现或转变为正向弹性关系。基于上述研究结果提出相应建议:区域城镇化发展介于(0.250,0.457]这一阶段的进程中,应把握住能源结构、居民消费率和产业结构对居民生活能源消费碳排放影响效应转变之前的阶段,鼓励居民生活消费,但进行节能低碳生活方式的引导,大力发展第三产业,满足居民对生活商品及服务的需求。当区域城镇化提升至0.457以上时,应合理优化能源结构,提高非化石能源比重,通过财政政策等对居民生活消费进行调控和引导,注重第三产业中的科技、金融等技术密集型的行业发展。