生计资本异质对农户农地流转行为的影响——以武汉城市郊区的516户农民为例

以武汉市城郊江夏区和蔡甸区的516户农民家庭为实证,运用logistic和分位数回归模型探索家庭生计资本对农户土地流转行为的影响及阈值。结果表明:(1)人力资本和金融资本与农户农地转出行为呈显著正向相关,家庭农地资源禀赋、机耕能力、社会资源禀赋及经营能力的信任程度等与农地转出行为负向相关。相反,自然资源禀赋及农业机械投入对农户土地转入行为的正向影响显著,而家庭融资能力则对农户转入行为呈显著的负向影响。(2)分位数回归结果显示,对农户土地流转行为存在影响阈值的仅有韧性指数。当农户家庭韧性指数≤2时,随韧性指数增强农户农地转出倾向愈强;家庭韧性指数≥3时,农户农地转出倾向随指数增强而弱化。该研究从农户微观个体视角探索生计资本异质对农地流转行为的影响,为针对农户家庭需求制定差别化的农地流转政策、有效推进农业适度规模经营提供建议参考。     

Supporting the risk management process with land information: a case study of Australia

It is frequently argued that, at the parcel level, 1 stakeholders are capable of and well supported in managing their land‐related risks. Yet, evidence from the contemporary Australian context suggests otherwise: numerous large‐scale disaster events have revealed that citizens are ill‐prepared to respond and recover adequately. This paper begins with the premise that information, specifically land information, could better support parcel‐level risk preparation, mitigation, response, and recovery. State land administration organisations in Australia primarily maintain this information and make it accessible. Land information is used regularly across all levels of government to support risk management activities; however, such application has not always occurred at the parcel and citizen level. Via a case study approach, this paper initially explores the land information available in Australia to stakeholders interested in parcel‐level detail, and then goes on to propose how the utilisation of parcel‐level land information could serve to enhance risk management practices.     

Defining disaster resilience: comparisons from key stakeholders involved in emergency management in Victoria,Australia

Three years after the introduction of the National Strategy for Disaster Resilience there remains no unanimously adopted definition of disaster resilience within Australia's emergency management sector. The aim of this study is to determine what the concept means to key stakeholders in the emergency management sector in the Australian State of Victoria, and how these conceptualisations overlap and diverge. Via an online survey, 113 people were asked how they define disaster resilience in their work in the emergency management sector. A data mining software tool, Leximancer, was employed to uncover the relationships between the definitions provided. The findings show that stakeholders see resilience as an ‘ability’ that encompasses emergency management activities and personal responsibility. However, the findings also highlight some possible points of conflict between stakeholders. In addition, the paper outlines and discusses a number of potential consequences for the implementation and the success of the resilience‐based approach in Australia.     

乡村韧性研究进展与展望

在快速城镇化背景下,各种不确定性扰动并制约着乡村可持续发展。乡村韧性作为乡村风险治理的一种新思路,已逐渐成为国内外学者广泛关注的新课题。在概述乡村韧性的缘起与概念演变的基础上,从乡村韧性的应用领域、社会—生态层面对乡村韧性的影响、乡村韧性评价等方面对当前乡村韧性的研究现状进行探讨,指出当前乡村韧性研究仍存在诸多薄弱环节,如:尚未形成公认的乡村韧性理论框架,应用性的乡村韧性实证研究相对薄弱,科学系统的乡村韧性评价体系构建有待完善。     

基于韧性理念的海岸带生态修复规划方法及应用

生态修复是海岸带空间规划的重要组成部分,而韧性理念中有关规划-吸收-恢复-适应的演化规律对于海岸带生态修复具有重要的指导意义。以沙化较为典型的海南木兰湾海岸带区域为例,开展海岸带国土空间生态修复规划的方法及应用研究,基于沙化脆弱性和生态系统服务的空间耦合分析划分不同类型空间,并分区制定生态修复规划方案。研究结果表明：（1）沙化脆弱性高的区域主要是旱地和沙地,面积达21.8%,生态系统服务高的区域主要是林地、水域、湿地,面积达67.5%。（2）重建修复区主要位于鱼塘、旱地一带,占总面积的16.4%;人工辅助修复区主要位于旱地以及迎风面一带,面积达5.5%;适度开发区多为基本完全沙化区域,面积为15.8%。相关评估结果和生态修复规划方案能够揭示生态系统各关键因子之间的胁迫-响应机理,为海岸带沙化区域的生态修复及恢复提供科学支撑。     

西部山区坡地村落空间演进与农户生计改变

坡地村落是指分布在山地、丘陵坡面上的村庄,广泛分布于我国的山区聚落中,是我国乡村聚落的重要类型。西部山区是坡地村落分布的主要地区,"十二五"期间随着主体功能区规划的实施,不仅会影响坡地村落的空间重组和人口迁移,也会影响到坡地村落的农户生计和山区区域发展问题。论文以坡地村落空间演进和农户流动为切入口,借助黄土高原和西南山地典型地区的分析,运用GIS和大比例尺地形图分析了坡地村落空间集中和分散的基本特征。通过实地考察和问卷分析,剖析了村落空间演进和人口流动过程中农户耕地资产、收入、基本生活方式等主要生计的改变。结论认为,以减缓生态环境压力、调和人地矛盾和扭转经济贫困为最初目标的人口迁移,总体来说,有着显著的正效应,主要表现在退耕使生态用地比重得到提高、劳动力收入渠道拓宽、基础设施和社会公共服务得到显著改善等方面。     

土壤微生物对环境胁迫的响应机制

微生物在生态系统物质循环和能量流动过程中起重要作用.研究土壤微生物对各种环境胁迫的响应有助于认识微生物对环境变化的适应与演变机理,维持土壤生态系统功能的稳定.土壤微生物群落多样性是衡量土壤生态系统稳定性的一个重要指标.多数研究表明,土壤微生物群落多样性越高,土壤生态系统越稳定.本文在总结土壤微生物群落多样性及其与环境胁迫响应关系的基础上,进一步讨论了土壤微生物对环境胁迫响应的生态学机制,包括:①抗性微生物的出现及抗性基因的水平转移.该过程导致了土壤微生物群落结构和多样性的改变,产生了更多抵抗能力较强的微生物类群,从而达到对外源干扰的适应,使土壤微生物群落对环境胁迫的抵抗力和恢复力随之提高.②土壤微生物群落功能的冗余.这些冗余程度越高,冗余组分缓冲维持生态系统正常功能的能力越强,从而提高微生物群落对环境胁迫的抵抗力和恢复力.研究土壤生态系统的稳定性与微生物多样性之间的关系,不仅有助于揭示土壤生态系统稳定性的内在机制,为合理调控提供科学依据,也可以为土壤环境质量管理提供参考.     

社会—生态系统适应性治理视角下绿地空间恢复力的演化——广州旧城区更新案例

旧城区绿地作为关键的社会—生态系统载体,是城市高质量发展与转型治理亟需关注的问题。构建广州旧城区绿地服务基本单元,引入适应性循环理论的潜力—连通度—恢复力三维框架,构建表征生态、社会与经济服务的绿地景观指标体系,综合评估2000—2018年广州旧城区绿地的空间恢复力水平及适应性转化特征。研究结果显示：旧城区绿地的恢复力演化具有明显的核心区与外围区的时空分异,在拆除重建阶段呈现快速开发—快速释放—重组的转化,在微更新阶段主要呈现开发—保护的提升,并具有提升型、稳定型和更替型的社会—生态系统服务适应性。由此说明,城市更新具有调节社会—生态系统服务治理的效果。其中,绿地形状指数、5 min可达绿地率以及土地利用混合度对核心区绿地恢复力具有显著的促进作用,为外围区治理提供参考。同时,进一步探讨了更新政策与城市绿地空间恢复力演化的关系,为促进旧城区绿地空间更新治理提供社会—生态系统适应性的理论与实证案例研究。     

西宁市PREE系统恢复力的定量评价

从社会-生态恢复力出发,引入PREE系统恢复力的内涵、特性以及研究意义;并从PREE系统结构确立恢复力定量评价的指标体系;提出用极差标准化对数据标准化、变异系数法确定权重等评价方法。然后实例对西宁市PREE系统恢复力进行了定量评价。评价结果表明西宁市PREE系统恢复力呈逐渐上升趋势,各子系统对于综合恢复力贡献大小不一,经济子系统对综合恢复力贡献最大,其次是环境子系统。     

Aligning science and policy to achieve evolutionarily enlightened conservation

There is increasing recognition among conservation scientists that long‐term conservation outcomes could be improved through better integration of evolutionary theory into management practices. Despite concerns that the importance of key concepts emerging from evolutionary theory (i.e., evolutionary principles and processes) are not being recognized by managers, there has been little effort to determine the level of integration of evolutionary theory into conservation policy and practice. We assessed conservation policy at 3 scales (international, national, and provincial) on 3 continents to quantify the degree to which key evolutionary concepts, such as genetic diversity and gene flow, are being incorporated into conservation practice. We also evaluated the availability of clear guidance within the applied evolutionary biology literature as to how managers can change their management practices to achieve better conservation outcomes. Despite widespread recognition of the importance of maintaining genetic diversity, conservation policies provide little guidance about how this can be achieved in practice and other relevant evolutionary concepts, such as inbreeding depression, are mentioned rarely. In some cases the poor integration of evolutionary concepts into management reflects a lack of decision‐support tools in the literature. Where these tools are available, such as risk‐assessment frameworks, they are not being adopted by conservation policy makers, suggesting that the availability of a strong evidence base is not the only barrier to evolutionarily enlightened management. We believe there is a clear need for more engagement by evolutionary biologists with policy makers to develop practical guidelines that will help managers make changes to conservation practice. There is also an urgent need for more research to better understand the barriers to and opportunities for incorporating evolutionary theory into conservation practice.