Montane Meadows as Indicators of Environmental Change

We used a time series of satellite multispectral imagery for mapping and monitoring six classes of montane meadows arrayed along a moisture gradient (from hydric to mesic to xeric). We hypothesized that mesic meadows would support the highest species diversity of plants, birds, and butterflies because they are more moderate environments. We also hypothesized that mesic meadows would exhibit the greatest seasonal and interannual variability in spectral response across years. Field sampling in each of the meadow types was conducted for plants, birds, and butterflies in 1997 and 1998. Mesic meadows supported the highest plant species diversity, but there was no significant difference in bird or butterfly species diversity among meadow types. These data show that it may be easier to detect significant differences in more species rich taxa (e.g., plants) than taxa that are represented by fewer species (e.g., butterflies and birds). Mesic meadows also showed the greatest seasonal and interannual variability in spectral response. Given the rich biodiversity of mesic montane meadows and their sensitivity to variations in temperature and moisture, they may be important to monitor in the context of environmental change     

京津冀地区面向人居环境之水安全格局初探

采用文献法对近年京津冀水资源、水环境、水污染、水灾害、水管理等水安全情势进行相关数据分析,从总体上显示出水危机问题和京津冀地区快速城市化发展的关联性.结果表明:1)京津冀城市群必须向节水型社会模式转型;2)建立区域及城市间的协调机制,才能有效克服流域与区域等级的水问题;3)实现京津冀地区水安全格局的治理行动计划网络,提出保护恢复体系、净化循环体系、限制节约体系、调度再造体系、蓄滞防洪减灾体系五大体系.     

粤港澳大湾区污染场地土壤风险管控制度体系建设与思考

防范污染场地环境风险和保障人居环境安全是粤港澳大湾区建设世界级城市群面临的重要挑战和工作内容之一.由于粤港澳在政治制度和土地管理等方面的差异,以及珠三角9市内部城市化水平、产业结构以及环境管理能力的差别,大湾区各地污染场地风险管控模式有明显的差异,分析粤港澳大湾区典型城市污染场地风险管控特点,对加强污染场地风险管控技术交流与合作,优化大湾区污染场地风险管控制度具有重要意义.本文在简述我国污染场地风险管控制度体系的基础上,重点介绍了广州、深圳、东莞、香港和澳门的污染场地风险管控制度体系、监管对象、污染评估与整治程序等的特点,对其风险管控制度体系进行了分析与对比,并针对土地规划、政策反馈、信息公开及联盟机制探索等提出了思考与建议.总体来看,香港及珠三角部分地市构建了行之有效的污染场地风险管控制度体系,且体现了一定的地方特点,但随着污染场地的进一步开发再利用,打造粤港澳大湾区世界级城市群的建设目标将对污染场地风险管控策略的安全性、精细化和时效性等提出更高的要求,互相借鉴和充分学习,加强大湾区2区9市污染场地风险管控上的技术交流与合作,是实现大湾区污染场地安全再利用与高效开发的有效路径.     

城市生活垃圾填埋场的物质存量特征及其环境影响:以粤港澳大湾区为例

填埋场中的生活垃圾成分复杂,即使在封场后其存量垃圾仍将持续产生温室气体、恶臭、地下水污染等环境问题,是城市生态环境修复的重点领域之一.生活垃圾填埋场物质存量、组成成分和理化特征是掌握其潜在环境影响的关键.但是目前关于填埋场物质存量及其环境影响的研究还不多见.本研究以我国城市化程度最高、人口最为密集的粤港澳大湾区城市群为例,基于国内外报道的科技信息和统计数据,对11个城市的生活垃圾产生量、处理量、组成成分、填埋场存量及关键元素碳存量进行分析.结果表明:①粤港澳大湾区2017年生活垃圾产生量为26. 4 Tg,平均每年增长0. 8 Tg,其中卫生填埋处置占58. 9%;②总生活垃圾填埋处置量为230. 1 Tg,其中食物、塑料和纸类垃圾的累计填埋处置量最多,分别为109. 6、38. 9和29. 6 Tg;③2001～2017年,大湾区城市生活垃圾填埋场总碳输入量为50. 0 Tg,通过填埋气排放的碳为7. 1 Tg,通过渗滤液排放的碳为1. 5 Tg,累积碳存量为41. 4 Tg.本研究可为研究城市生活垃圾填埋场的环境影响提供基础数据,为大湾区城市生态环境修复提供科学依据.     

基于Sentinel-5P的粤港澳大湾区NO2污染物时空变化分析

基于最新的TROPOMI反演的对流层NO₂垂直柱浓度数据,利用Google Earth Engine平台分析了粤港澳大湾区近2a对流层NO₂垂直柱浓度的分布及变化特征.结果表明, TROPOMI传感器反演的对流层NO₂垂直柱浓度与地表NO₂浓度监测值具有较好的相关性,反演产品能够反映地面真实的NO₂污染状况;粤港澳大湾区NO₂柱浓度分布呈现出较为显著的圈层结构,高NO₂柱浓度区域面积约为4468km²,占大湾区总面积的8%,低NO₂柱浓度地区的面积约为25331km²,占比超过了45%;大湾区上空的对流层NO₂垂直柱浓度存在明显的“冬高夏低,春秋过度”的季节性差异和周期性波动特征;影响因子回归模型结果表明人类活动强度(DNB,夜间灯光)、植被状况(NDVI,植被指数)和地形因子(DEM,数字高程)与地区对流层NO₂垂直柱浓度的分布有明显的相关性.本研究成果可为政府和决策者制定相关政策和措施提供借鉴.     

The Contribution of Habitat Loss to Changes in Body Size, Allometry, and Bilateral Asymmetry in Two Eleutherodactylus Frogs from Puerto Rico

Abstract:  Amphibian populations have been declining worldwide and the exact mechanisms underlying these changes are not well understood. We examined environmentally induced phenotypic changes that may reflect ongoing stresses on individuals and therefore their ability to persist in increasingly changing landscapes. Specifically, we evaluated the contribution of habitat loss on the size, allometry, and levels of fluctuating asymmetry of Eleutherodactylus antillensis and E. coqui , 2 common species that are endemic to Puerto Rico. We x-rayed frogs collected at 9 sites that differed in the amount of forest cover and measured their snout-vent, radio-ulna, femur, and tibio-fibula lengths. E. antillensis and E. coqui were smaller in the highly disturbed (≤20% forest cover) than in the intermediately (20–70% forest cover) and little-disturbed (≥70% forest cover) landscapes. In E. antillensis but not in E. coqui , the slope and intercept of the curves relating snout-vent length with the length of the 3 bones differed with degree of forest cover, suggesting an effect of habitat loss on body shape. In E. antillensis and E. coqui , differences between right and left sides corresponded to true fluctuating asymmetry; however, only the radio-ulna length of E. coqui showed a trend toward an increase in fluctuating asymmetry with habitat loss. Because body size scales with a variety of physiological, life history, and ecological traits, conservation programs aimed at monitoring morphological changes in amphibians may help in understanding the mechanisms that contribute to their persistence in changing environments.     

SALINITY INCREASES IN THE NAVAJO AQUIFER IN SOUTHEASTERN UTAH1

ABSTRACT: Salinity increases in water in some parts of the Nava-jo aquifer in southeastern Utah have been documented previously. The purpose of this paper is to use bromide, iodide, and chloride concentrations and del oxygen-18 and deuterium values in water from the study area to determine if oil-field brines (OFB) could be the source of increased salinity. Mixing-model results indicate that the bromide-to-chloride X 10,000 weight ratio characteristic of OFB in and outside the study area could not be causing the bromide depletion with increasing salinity in the Navajo aquifer. Mixing-model results indicate that a mixture of one percent OFB with 99 percent Navajo aquifer water would more than double the bromide-to-chloride weight ratio, instead of the observed decrease in the weight ratio with increasing chloride concentration. The trend of the mixing line representing the isotopically enriched samples from the Navajo aquifer does not indicate OFB as the source of isotopically enriched water; however, the simulated isotopic composition of injection water could be a salinity source. The lighter isotopic composition of OFB samples from the Aneth, Ratherford, White Mesa Unit, and McElmo Creek injection sites relative to the lsmay site is a result of continued recycling of injection water mixed with various proportions of isotopically lighter make-up water from the alluvial aquifer along the San Juan River. A mixing model using the isotopic composition of the simulated injection water suggests that enriched samples from the Navajo aquifer are composed of 36 to 75 percent of the simulated injection water. However, chloride concentrations predicted by the isotopic mixing model are up to 13.4 times larger than the measured chloride concentrations in isotopically enriched samples from the Navajo aquifer, indicating that injection water is not the source of increased salinity. Geochemical data consistently show that OFB and associated injection water from the Greater Aneth Oil Field are not the source of salinity increases in the Navajo aquifer.     

Environmental impact assessment in the association of southeast Asian Nations

The Association of Southeast Asian Nations has agreed that environmental protection and sustainable use of natural resources are essential for sound economic development. The Environmental Impact Assessment is viewed as an important management tool and an ASEAN Experts Group on the Environment has been working for several years on a model especially adapted to the region and also on case studies of the implementation of EIA. Progress so far has been frustratingly slow due to misunderstanding, a lack of ecological data, inadequate trained manpower and institutional shortcomings for compliance. The author advocates collaboration on an ASEAN model for performing EIA as a means of accelerating acceptance and implementation. The concept of Adaptive Environmental Assessment and Management is proposed as a prototype.     

The Greater Yellowstone Ecosystem: Challenges for Regional Ecosystem Management

An adaptive management approach is necessary but not sufficient to address the long-term challenges of the Greater Yellowstone Ecosystem (GYE). Adaptive management, in turn, has its own particular challenges, of which we focus on two: science input, and stakeholder engagement. In order to frame our discussion and subsequent recommendations, we place the current management difficulties into their historical context, with special emphasis on the 1990 Vision document, which attempted a broad synthesis of management goals for the ecosystem. After examining these two key challenges in the context of the GYE, we make several recommendations that would allow for more effective ecosystem management in the long term. First, we recommend adoption of the GYE as a site for long-term science research and monitoring with an emphasis on integrative research, long-term federal funding, and public dissemination of data. Second, we conclude that a clearer prioritization of legislative mandates would allow for more flexible ecosystem management in the GYE, a region where conflicting mandates have historically led to litigation antithetical to effective ecosystem management. Finally, we recommend a renewed attempt at an updated Vision for the Future that engages stakeholders (including local landholders) substantively from the outset.     

城市红树林生态系统健康评价与管理对策——以粤港澳大湾区为例

为解明粤港澳大湾区城市红树林生态系统健康状况,基于PSR (压力-状态-响应)模型和层次分析法,构建了城市红树林生态系统健康评价指标体系,对大湾区的香港米埔、深圳福田、广州南沙和珠海淇澳岛4个典型城市红树林进行生态系统健康评价,识别健康问题并提出管理对策.结果表明:红树林生态系统健康指数(EHI)为淇澳岛(3.05,健康)>米埔(3.03,健康)>南沙(2.54,亚健康)>福田(2.13,亚健康).就压力指标而言,米埔和福田红树林的自然压力源为病虫害和生物入侵,人为压力源为人口、经济相关指标及城镇生活污水排放,福田还受到工业废水排放的压力.就状态指标而言,红树林受海水营养盐污染严重,南沙和淇澳岛红树林存在严重的有机污染和重金属污染;红树植物多样性(除南沙红树林外)和大型底栖动物生物多样性偏低,但鸟类生物多样性处于较高水平.就响应指标而言,福田和南沙红树林由于面积小而生态服务功能偏低,南沙红树林的管理水平不足.粤港澳大湾区城市红树林存在的主要健康问题包括生态失衡导致的病虫害与生物入侵、受纳外源污染导致的环境污染、栖息地破坏导致的生物多样性下降的共性问题及自身特征与管护水平差异导致的其它个性问题.针对上述健康问题,建议:以缓解生态失衡为目标高效监测并推广基于自然法则的生态恢复,以源头控制为根本整体改善环境质量,以保护生物多样性为重点提高红树林生态系统稳定性,因地制宜充分发挥城市红树林经济-社会-生态效益.