基于能值分析的滨海湿地生态系统服务价值定量化研究进展

在滨海湿地生态系统服务价值评价中,能值方法克服了传统经济学方法的一些不足,对评价沿海地区发展的可持续性具有重要意义,并成为近十年来环境经济学和生态经济学研究的热点问题。综合国内外滨海湿地生态系统服务价值能值评价的研究进展,就滨海湿地生态系统的供给、调节、文化和支持服务价值的能值估算方法进行了分析。在此基础上,指出了目前该方法应用于滨海湿地生态系统服务价值评价主要存在能值转换率的选用不一致、生态系统服务价值的能值估算方法需要完善、能值分析所应用的滨海湿地类型较少、缺少对人类活动引起的生态系统服务能值变化的评价及检验评价结论正确性的标准等不足,并提出了进一步的研究方向。     

南水北调中线丹江口库区土地生产潜力估算

以土地生产潜力与承载力理论为基础,以南水北调中线工程主要淹没区和水源地——丹江口库区耕地为研究对象,在遥感影像、DEM、气象、土壤等数据支持下建立模型,利用潜力递减法估算丹江口库区的土地生产潜力,同时对土地资源人口承载力进行研究。估算结果表明:研究区不同作物、不同耕作制度下的最大生产潜力与现实生产力有很大差距,在现有粮食生产水平下,库区未淹没耕地的情况下,库区的人口承载力现状已经很差,当水位达到170 m后,库区人口承载力将进一步恶化。但是,研究区作物的现实生产力还有很大的提高余地,若在移民的前提下,深入挖掘土地生产潜力,因地制宜的选择合适的耕作制度,库区的土地承载力还可以有所提高。     

Mg3MnxAl1-xCO3类水滑石衍生NSR催化剂的制备及其性能评价

采用共沉淀法合成了三元类水滑石Mg_3Mn_xAl_(1-x)CO_3,通过高温煅烧得到其衍生氧化物Mg_3Mn_xAl_(1-x)O_m,再经浸渍负载Pt或BaO后制得新型NO_x存储/再还原(NSR)催化剂。XRD及SEM表征结果显示,当Mn与Al的摩尔比(Mn/Al)大于1时所制备的Mg_3Mn_xAl_(1-x)O_m有杂晶相出现且发生团聚,结合NO_x存储性能评价结果,确定最优Mn/Al为1。BaO负载不利于NO_x的存储,而当Pt负载量为1%(w)时NO_x存储性能最优,250℃条件下的存储量由负载前的0.52 mmol/g提升至0.61 mmol/g。CO_2与NO_x之间存在较强的竞争吸附。负载1%Pt催化剂的NSR性能评价结果表明,8个稀燃-富燃循环后NO_x的去除率为68%,表明催化剂的还原性能仍需加强。     

绿色“一带一路”建设研究及建议

生态环保是"一带一路"建设的重要内容。在2017年5月14日召开的"一带一路"国际合作高峰论坛系列成果清单包括《关于推动绿色"一带一路"建设的指导意见》、《"一带一路"生态环境保护合作规划》、"一带一路"生态环保大数据服务平台建设、"一带一路"绿色发展国际联盟建立等四项。为更好地理解和推动执行,本文全面进行了分析,并提出下一步推动绿色"一带一路"工作需要解决的关键问题和建议。     

Capacity building for food justice in England: the contribution of charity-led community food initiatives

This paper discusses the extent to which charity-led initiatives can contribute to capacity building for food justice in England. The paper draws on evaluations of two projects run by the charity Garden Organic: the Master Gardener Programme, operating a network of volunteers who mentor households, schools and community groups to support local food growing, and the Sowing New Seeds programme, which engages “Seed Stewards” to work with communities to encourage the growing and cooking of “exotic” crops. Based on qualitative data about peoples’ motivations for participation and the benefits that are experienced, we interpret these projects as examples of capacity building for food justice. We suggest that whilst currently depoliticised, the “quiet” process of reskilling and awareness raising that occurs through shared gardening projects could have transformative potential for people’s relationship with food. Finally, we use our findings to raise critical questions and propose future research about food justice concepts and practices.     

Characterization of aluminium-based water treatment residual for potential phosphorus removal in engineered wetlands

Aluminium-based water treatment residual (Al-WTR) is the most widely generated residual from water treatment facilities worldwide. It is regarded as a by-product of no reuse potential and landfilled. This study assessed Al-WTR as potential phosphate-removing substrate in engineered wetlands. Results indicate specific surface area ranged from 28.0 m² g⁻¹ to 41.4 m² g⁻¹. X-ray Diffraction, Fourier transform infrared and energy-dispersive X-ray spectroscopes all indicate Al-WTR is mainly composed of amorphous aluminium which influences its phosphorus (P) adsorption capacity. The pH and electrical conductivity ranged from 5.9 to 6.0 and 0.104 dS m⁻¹ to 0.140 dS m⁻¹ respectively, showing that it should support plant growth. Batch tests showed adsorption maxima of 31.9 mg P g⁻¹ and significant P removal was achieved in column tests. Overall, results showed that Al-WTR can be used for P removal in engineered wetlands and it carries the benefits of reuse of a by-product that promotes sustainability.     

碱激发胶凝材料及其固化Pb^2＋的试验研究

对碱激胶凝材料（碱-偏高岭土、碱-矿渣和碱-粉煤灰）与水-水泥体系固化Ph^2＋进行了试验研究,其中水-水泥体系为对比样。结果表明：对于相同稠度的碱激发胶凝材料,即使Pb^2＋含量达到2．4％,除了碱-粉煤灰的抗压强度略低外,其他都达到30MPa以上,满足填埋或做建筑基材的使用要求;与水泥相比,碱激发胶凝材料能显著降低重金属离子（Ph^2＋）浸出浓度,其规律性与其NH4交换容量大小的规律性一致,与其固化体的抗压强度的大小没有相关性。     

Wood bison population recovery and forage availability in northwestern Canada

Forage availability was assessed to determine sustainable stocking rates for eight broadly defined vegetation types (Treed Uplands, Treed Lowlands, Mixed Tall Shrub/Sedge, Closed-canopied Willow, and Open-canopied Willow, Meadow, Wetland Grass, Wetland Sedge) for use by wood bison (Bison bison athabascae), a threatened subspecies, in the Canadian boreal forest of northern Alberta. Clip plots (n=108) were used to sample peak availability of herbs and current annual growth of Salix spp. in late summer. Graminoid wetlands dominated by Carex atherodes, Carex aquatilis, Carex utriculata, Scolochloa festucacea, or Calamagrostis stricta produced 1975-4575 kg ha(-1) of fair to good quality forage, whereas treed stands produced < 250 kg ha(-1) of forb-dominated forage (>85% content), which was below a published 25% foraging efficiency threshold of 263 kg ha(-1) for bison. Upland forests that dominate the region produced < or = 1 animal unit day (AUD) of forage per hectare in summer. Most forest understory plants were of poor forage value, suggesting the potential sustainable stocking rate of such areas was actually < or = 0.3 AUD ha(-1), with even lower rates during winter due to snow cover. Herbaceous wetlands contained approximately 78 AUD ha(-1) of forage, but were considered largely unavailable in summer because of flooding and soft organic soils that make access difficult. Conversion of prime foraging habitat to agricultural land, forest expansion due to fire control, and a warmer and wetter climatic regime after the mid-1900s likely contributed to a regional reduction in carrying capacity. It is hypothesized that substantial recovery of the wood bison population toward historical levels will be constrained in northern Alberta by the availability of summer forage, and the limited extent of graminoid wetlands that provide winter foraging habitat.     

The geography of conflict between elk and agricultural values in the Cypress Hills, Canada

Complex ecological issues like depredation and its management are determined by multiple factors acting at more than one scale and are interlinked with complex human social and economic behaviour. Depredation by wild herbivores can be a major obstacle to agricultural community support for wildlife conservation. For three decades, crop and fence damage, competition with livestock for native rangeland and tame pasture, and depredation of stored feed by elk (Cervus elaphus canadensis) have been the cause of conflict with agricultural producers in the Cypress Hills, Alberta and Saskatchewan. Tolerance of elk presence on private lands is low because few benefits accrue to private landowners; rather they largely perceive elk as a public resource produced at their expense. Government management actions have focused on abatement inputs (e.g., population reduction; fencing) and compensation, but incentives to alter land use patterns (crop choice and location) in response to damages have not been considered. Nor has there been information on spatial structure of the elk population that would allow targeted management actions instead of attempting to manage the entire population. In this study we analysed the spatial structure of the Cypress Hills elk population, the distribution of the elk harvest in relation to agricultural conflicts, developed models of the spatial patterns of conflict fields, and evaluated compensation patterns for damage by wild herbivores. We propose modifications to current abatement and compensation programs and discuss alternative approaches involving changes to agricultural land use patterns that may reduce the intensity of conflicts with elk, and increase the acceptance capacity of landowners.     

Shrub Encroachment Impacts the Potential for Multiple Use Conflicts on Public Land

Public rangelands in North America are typically managed under a multiple use policy that includes livestock grazing and wildlife management. In this article we report on the landscape level extent of grassland loss to shrub encroachment in a portion of the Rocky Mountain Forest Reserve in southwestern Alberta, Canada, and review the associated implications for simultaneously supporting livestock and wildlife populations while maintaining range health on this diminishing vegetation type. Digitized aerial photographs of 12 km of valley bottom from 1958 and 1974 were co-registered to ortho-rectified digital imagery taken in 1998, and an un-supervised classification used to determine areas associated with grassland and shrubland in each year. Field data from 2002 were over-layed using GPS coordinates to refine the classification using a calibration-validation procedure. Over the 40-year study period, open grasslands declined from 1,111 ha in 1958 to 465 ha in 1998, representing a 58% decrease. Using mean production data for grass and shrub dominated areas we then quantified aggregate changes in grazing capacity of both primary (grassland) and secondary (shrubland) habitats for livestock and wildlife. Total declines in grazing capacity from 1958 to 1998 totaled 2,744 Animal Unit Months (AUMs) of forage (−39%), including a 58% decrease in primary (i.e., open grassland) range, which was only partly offset by the availability of 1,357 AUMs within less productive and less accessible shrubland habitats. Our results indicate shrub encroachment has been extensive and significantly reduced forage availability to domestic livestock and wildlife, and will increase the difficulty of conserving remaining grasslands. Although current grazing capacities remain marginally above those specified by regulated grazing policies, it is clear that continued habitat change and decreases in forage availability are likely to threaten the condition of remaining grasslands. Unless shrub encroachment is arrested or grassland restoration initiated, reductions in aggregate ungulate numbers may be necessary.