Drivers of mangrove ecosystem service change in the Sundarbans of Bangladesh

Mangroves are now well known to provide a range of ecosystem services that benefit local populations, though such ecosystem services are at risk from mangrove deforestation and degradation across much of the tropics. This study aimed to identify the natural and anthropogenic drivers of change that affect ecosystem services of the Sundarbans mangrove forest. Secondary data analysis and primary fieldwork were conducted in three districts in the Sundarbans region of Bangladesh to understand ecosystem service usage and the perceptions of local resource users. Time series data for a range of ecosystem services and biophysical, socio‐economic variables were analyzed to identify the range of trends and the significant drivers of change. Also, community perceptions were consulted to elicit how these changes are felt and how they affected the local ecosystem services users. Results show that most of the ecosystem services of the Sundarbans experienced negative changes over the last two decades. Time series analysis and community perceptions held a number of drivers responsible for these changes. Climatic change, rapid environmental change, demand for mangrove products on the global market, major infrastructure development and governance failure were identified as primary drivers leading to the degradation of ecosystem services of the Sundarbans. The study calls for a transformation in the stewardship of ecosystem services of the Sundarbans and other mangroves across the tropics, to escape the situation where negative environmental impacts might be difficult to reverse.     

雄安新区生态安全格局识别与优化策略

雄安新区的设立对于调整、优化京津冀城市空间结构具有深远的历史意义。面向“生态标杆”的新区建设理念,生态安全格局识别及优化是保障雄安新区生态安全、实现可持续发展的基本空间途径。本文基于雄县、容城、安新三县生态本底特征,选取并定量评估粮食供给、产水、土壤保持、生境维持和近水游憩5种生态系统服务,识别生态源地;利用VIIRS/DNB夜间灯光数据修正基于地类赋值的基本阻力面,并运用最小累积阻力模型识别生态廊道;最后基于现状生态安全格局,探讨绿色生态宜居新城目标下的生态安全格局优化策略。研究结果表明：雄安三县生态源地占到全区土地总面积的41.88%,包含14个生态源地斑块,主要分布在白洋淀周边;生态廊道总长度107.21 km,分4大组团呈环状分布;现有生态源地辐射面积占到全区的70.6%,在雄县县城周边新建辐射面积为227 km²的生态源地可满足全区85%的源地辐射面积规模要求。本文提出的生态安全格局优化方案可为雄安新区开发建设提供空间指引。     

LBS中多尺度空间方位的自然语言描述

位置服务是地理信息系统（GIS）应用的重要领域,GIS提供关于空间位置的坐标描述,但这不符合人们的认知和日常习惯。地理空间中人们日常的交流通常使用方位描述。基于自然语言的空间方位的描述对移动目标（如驾驶员）是十分重要的,通过规范的地点描述语言进行快速的地理定位,可提高人的空间反应和处理能力。本文依据人的多尺度空间认知,分析空间参考和定位习惯,结合自然语言描述知识,利用GIS分析功能,给出多尺度环境下空间方位的自然语言描述。     

关于信息化测绘体系建设目标和任务的探讨

简要回顾了我国测绘体系的发展历程,并对传统测绘体系、数字化测绘体系和信息化测绘体系三个阶段的主要区别进行了概括,进而对信息化测绘体系的建设目标及主要任务进行了重点讨论。     

Expanding networks for the urban poor: Water and telecommunications services in Lima, Peru

In many cities of the developing world, poor residents occupy land and build their dwellings before infrastructure is provided. Expanding the infrastructure networks for the poor is a long, expensive and complicated affair. Before the 1990s, the public sector was generally in charge of the basic services; but these services have been liberalized and, in many cases, privatized since then. In this new context, a relevant question is: have these reforms contributed to urban integration? Or, on the contrary, have they contributed to deepen urban fragmentation? This study presents the case of water and telecommunications services in Lima, Peru, the most contested and politically sensitive urban sectors. The objective is to test Graham and Marvin’s claims about the splintering of networked infrastructures expressed in Splintering Urbanism.The findings show that the reforms have improved the situation at aggregate level, but there is still no sustainable solution for the crucial dilemma of cities with high poverty restrictions: self-financed network expansions versus service affordability. The diverging paths of the utilities reform in Lima illustrate that privatization is not the main issue in the discussion to expand the networks for the poor. The main conclusion is that sensible policies complemented with carefully targeted subsidies and continuous regulation can successfully provide water for all. Good governance practices at the urban level help to achieve this goal. Water and telecommunications in Lima also show that are no general solutions for the universalization of the services; each city is different and some sectors are much more complex and problematic than others. This demands careful and continuous technical and political consideration of the local circumstances to reform the utilities.     

Assisted tree migration can reduce but not avert the decline of forest ecosystem services in Europe

European forests are facing multiple natural and anthropogenic pressures that are expected to become more severe in the next decades. Tree diversity is projected to decline in many areas across the continent. How this will affect the provision of forest services remains an open question, whose answer depends, among others, on the practical and theoretical challenges of incorporating assisted migration into climate adaptation strategies. Here, we tackle the issue by combining a large dataset of tree species occurrences, future climatic projections, and data on tree functional traits and tree-specific forest services into a novel modelling framework. We estimate that, by the end of the century and under a natural dispersal scenario, the provision of forest services would decrease on average by 15% in Europe (for RCP 4.5; 23% for RCP 8.5), and up to 52% (70% for RCP 8.5) in the Mediterranean. To explore if and how management could reduce the projected losses, we simulated a suite of alternative assisted migration strategies aimed at identifying, for each locality, the tree species communities offering the best compromise in terms of resilience to climate change and delivery of specific combinations of ecosystem services. Such strategies could reduce losses of services by 10% (15%) on average in Europe, and even increase service availability in the Alpine and Boreal regions but not in the Mediterranean, where losses will remain as high as 33% (54% for RCP 8.5). Our findings highlight how science-driven management strategies could be vital to reduce an otherwise dramatic, European-wide decline of forest services. Our results are qualitatively robust to different assumptions on future carbon emissions and related climate trajectories. That is, our simulated assisted migration strategies identify similar tree species communities under different pathways (RCP 4.5 vs RCP 8.5). This makes our approach a powerful tool for forest management, as it generates advice that is valid regardless of whether, and to what extent, human society will steer away from business-as-usual emission trajectories.     

多距离模式的长沙某医院服务范围空间分析

对长沙市某医院2016年1~3月份的就诊患者地址数据进行地理编码及可视化处理,采用欧式距离、曼哈顿距离、道路距离、最短行驶时间方法分析不同距离模式下患者到该医院就医的空间分布状况;另外,结合分位数评价指标定量分析3种距离模式下服务半径和服务面积的异同以及影响该医院服务范围的因素,分析得到该医院的服务范围呈中心辐射状,主要服务半径较小(约8 km),服务辐射范围在150 km~2以内,且受距离成本、时间成本和地形要素影响明显。     

Preference for Grassland Heterogeneity: Implications for Biodiversity in the Great Plains

The Great Plains of the United States is a grassland region managed primarily for homogeneity associated with production agriculture. The resulting decline of obligate fauna makes enhancing biodiversity an increasingly important ecological goal. A survey was administered to land managers and the general population in ranching regions of Nebraska, Kansas, Oklahoma, and the Texas Panhandle. This research explores the preferred characteristics of privately owned grasslands among ranchers and the general population for vegetation structure and biodiversity. Results indicate a knowledge gap between biodiversity and the vegetation heterogeneity required to support it. Preference for grassland structure is seen as a sociocultural driver of decisions on management practices that constrain adoption of heterogeneity management. Conserving biodiversity and enhancing ecosystem services provided by heterogeneous grasslands can be accomplished by demonstrating that conservation advantages of heterogeneity and production agriculture are compatible.     

Participatory 3D modelling as a socially engaging and user-useful approach in ecosystem service assessments among marginalized communities

Land use decision making in the Upper Suriname River area knows a history of disempowerment and marginalization of the Saamaka communities inhabiting the area. Non-recognition of land rights is at the origin of this problem. This is aggravated by the increasing over-exploitation of timber resources by powerful stakeholders and the unfair distribution of timber benefits. This has left Saamakans marginalized, causing distrust and opposition among themselves and towards outsiders. Furthermore, as a result of deforestation, Saamakans face detrimental changes in the ecosystem services (ES) that support their traditional livelihoods, with important effects for their wellbeing. This environment of distrust, opposition and marginalization makes it difficult to assess these concerns. Hence, an ES assessment approach that would generate salient ES knowledge while generating trust, communication among stakeholders and local capacity building was needed. In this paper we evaluate whether Participatory 3D modelling (P3DM) is an effective approach for ecosystem services assessments in such disenabling environments. We evaluate this by using empirical data from an ES assessment in the Saamaka region using a P3DM approach. Results show the efficient identification and evaluation of 36 ES representing provisioning, cultural and regulating service categories with crops, fish, wild meat, timber and forest medicines identified as most important. We found a decrease in the demand and supply of crops, fish and wild meat associated with ecosystem degradation, out-migration and changes in lifestyles. Further, our findings show an increasing demand and decreasing supply for timber related to over-exploitation. We provide evidence of the utility of P3DM to foster multi-functional landscape development among wary communities. Further, we discuss the usefulness of the approach and the necessary conditions needed for P3DM process to tackle the needs of the local communities as well as the need for a broader P3DM implementation strategy beyond the engagement, screening, and diagnostic phases of ES assessments when the aim is to enhance ES outcomes for marginalized communities.     

The challenge of valuing ecosystem services that have no material benefits

Since the Millennium Ecosystem Assessment, ecosystem service science has made much progress in framing core concepts and approaches, but there is still debate around the notion of cultural services, and a growing consensus that ecosystem use and ecosystem service use should be clearly differentiated. Part of the debate resides in the fact that the most significant sources of conflict around natural resource management arise from the multiple managements (uses) of ecosystems, rather than from the multiple uses of ecosystem services.If the ecosystem approach or the ecosystem service paradigm are to be implemented at national levels, there is an urgent need to disentangle what are often semantic issues, revise the notion of cultural services, and more broadly, practically define the less tangible ecosystem services on which we depend. This is a critical step to identifying suitable ways to manage trade-offs and promote adaptive management.Here we briefly review the problems associated with defining and quantifying cultural ecosystem services and suggest there could be merit in discarding this term for the simpler non-material ecosystem services. We also discuss the challenges in valuing the invaluable, and suggest that if we are to keep ecosystem service definition focused on the beneficiary, we need to further classify these challenging services, for example by differentiating services to individuals from services to communities. Also, we suggest that focussing on ecosystem service change rather than simply service delivery, and identifying common boundaries relevant for both people and ecosystems, would help meet some of these challenges.