The Transboundary Nature of the Allende–Piedras Negras Aquifer Using a Numerical Model Approach

The Allende–Piedras Negras (APN) aquifer is located between the states of Texas (United States [U.S.]) and Coahuila (Mexico). The Rio Grande crosses the aquifer, acting as a natural and political divide between the countries. However, it remains unclear whether the APN aquifer can be considered a truly transboundary aquifer flow system, which would potentially require joint management by two different administrative jurisdictions. The main purpose of this study was to evaluate the transboundary nature of this aquifer. This was achieved by developing a detailed hydrogeological model to analyze the direction of volumetric fluxes within the APN aquifer using Visual MODFLOW. The model simulated a spatially averaged cumulative drawdown of 0.76 m for the entire aquifer over an 18‐year modeling period (2000–2017). The flow convergence zone, previously located below the Rio Grande, has shifted to the U.S. side in most locations, driven by higher pumping rates of the wells located near the river. This shift of the convergence zone from one country to the other means that groundwater recharge from one side flows underneath the river to the other side. This qualifies the APN aquifer as a “transboundary groundwater flow system.” The procedure followed in this study may be applied to other aquifers that straddle the U.S.–Mexico border and may motivate future modeling studies on other poorly studied transboundary aquifers around the world and thereby enable bi‐national aquifer management.     

Human–wildlife coexistence in a changing world

Human–wildlife conflict (HWC) is a key topic in conservation and agricultural research. Decision makers need evidence-based information to design sustainable management plans and policy instruments. However, providing objective decision support can be challenging because realities and perceptions of human–wildlife interactions vary widely between and within rural, urban, and peri-urban areas. Land users who incur costs through wildlife argue that wildlife-related losses should be compensated and that prevention should be subsidized. Supporters of human–wildlife coexistence policies, such as urban-dwelling people, may not face threats to their livelihoods from wildlife. Such spatial heterogeneity in the cost and benefits of living with wildlife is germane in most contemporary societies. This Special Section features contributions on wildlife-induced damages that range from human perspectives (land use, psychology, governance, local attitudes and perceptions, costs and benefits, and HWC and coexistence theory) to ecological perspectives (animal behavior). Building on current literature and articles in this section, we developed a conceptual model to help frame HWC and coexistence dimensions. The framework can be used to determine damage prevention implementation levels and approaches to HWC resolution. Our synthesis revealed that inter- and transdisciplinary approaches and multilevel governance approaches can help stakeholders and institutions implement sustainable management strategies that promote human–wildlife coexistence.     

跨边界区域水资源冲突与协调模型与应用(Ⅰ)模型体系

针对水量短缺和水质污染引起的跨边界区域水资源冲突 ,运用大系统分解协调原理和博奕理论构建了跨边界区域水资源冲突与协调模型体系 .该模型体系通过在行政边界出境处设置控制断面 ,按生活、生产、生态用水分类预测了未来断面控制区域的用水量和水污染物排放量 ,在此基础上建立了断面非合作与合作模型对冲突中的竞争和合作行为进行模拟 ,并选用纳什法协调冲突 .模型确保了河道的最小生态用水需求 ,并通过关联预估法协调模型中的水量子系统和水质子系统 ,模型既可对断面水量进行优化调度 ,又可对断面水污染物排放进行总量控制 .     

跨界流域污染防治:基于合作博弈的视角

随着经济的高速发展,跨界流域污染问题在我国越发严重起来.从国外解决跨界流域污染的实践经验来看,各个地区采取合作治理污染物的方式防治跨界流域污染,是解决跨界流域污染问题比较经济可行的方式.从国内外众多研究来看,现有研究仅限于利用博弈理论分析完全合作情况下的收益分配问题,并没有对收益分配后,各合作者所形成的合作是否稳定、收益分配是否公平进行讨论与深入分析.论文以此为切入点,利用跨界流域污染合作治理思路,以河南省贾鲁河流域的4 个地区为实证研究对象进行了实证分析.从博弈理论的角度详细地分析了各个地区进行合作防治跨界流域污染的思路、方式,并对各个地区之间进行合作治理污染物时的稳定性进行了讨论.研究结果显示,在进行合作治理污染物时,不同地区的边际污染物减排成本差异是各个地区能否进行合作防治跨界流域污染的关键,并且不同的收益/成本分担机制对不同地区长期、稳定地开展合作治理污染物也有较大的影响.     

Potential Effects of the United States-Mexico Border Fence on Wildlife

Abstract:  Security infrastructure along international boundaries threatens to degrade connectivity for wildlife. To explore potential effects of a fence under construction along the U.S.–Mexico border on wildlife, we assessed movement behavior of two species with different life histories whose regional persistence may depend on transboundary movements. We used radiotelemetry to assess how vegetation and landscape structure affect flight and natal dispersal behaviors of Ferruginous Pygmy-Owls ( Glaucidium brasilianum ), and satellite telemetry, gene-flow estimates, and least-cost path models to assess movement behavior and interpopulation connectivity of desert bighorn sheep ( Ovis canadensis mexicana ). Flight height of Pygmy-Owls averaged only 1.4 m (SE 0.1) above ground, and only 23% of flights exceeded 4 m. Juvenile Pygmy-Owls dispersed at slower speeds, changed direction more, and had lower colonization success in landscapes with larger vegetation openings or higher levels of disturbance ( p ≤ 0.047), which suggests large vegetation gaps coupled with tall fences may limit transboundary movements. Female bighorn sheep crossed valleys up to 4.9 km wide, and microsatellite analyses indicated relatively high levels of gene flow and migration (95% CI for F_ST= 0.010–0.115, Nm = 1.9–24.8, M = 10.4–15.4) between populations divided by an 11-km valley. Models of gene flow based on regional topography and movement barriers suggested that nine populations of bighorn sheep in northwestern Sonora are linked by dispersal with those in neighboring Arizona. Disruption of transboundary movement corridors by impermeable fencing would isolate some populations on the Arizona side. Connectivity for other species with similar movement abilities and spatial distributions may be affected by border development, yet mitigation strategies could address needs of wildlife and humans.     

生物监测在跨界河流中的应用进展

综合分析了生物监测在跨界河流流经国家间的协调管理、生物类群的选择以及监测技术的选择方面所面临的问题;选择欧洲多瑙河、亚洲湄公河以及非洲尼日尔河等跨界河流作为典型案例,对比分析使用不同生物类群(例如底栖动物、浮游藻类以及鱼类)进行跨界河流生物监测的技术方法,阐述了跨界生物监测项目中的资金来源、管理办法和运行机制等;并对未来的跨界河流生物监测提出建议,以期为中国的跨界河流生物监测提供实践依据。     

中国控制危险废物越境转移管理现状与展望

按照环境无害化管理原则,严格限制危险废物越境转移活动是中国履行《控制危险废物越境转移及其处置巴塞尔公约》的重要内容。本研究通过梳理《控制危险废物越境转移及其处置巴塞尔公约》关于控制危险废物越境转移的主要规定和中国立法管理实践,全面分析了中国控制危险废物越境转移管理进展。从打击非法转移、完善法律基础、建立预警机制等方面,深入剖析了中国控制危险废物越境转移面临的形势,并从强化危险废物越境转移管控、严厉打击非法出口行为、联合海关部门加强日常监管三方面提出对策建议,以期为中国全面履行《控制危险废物越境转移及其处置巴塞尔公约》要求、控制和防范危险废物越境转移环境风险提供支撑。     

Wildlife impacts and vulnerable livelihoods in a transfrontier conservation landscape

Interactions between humans and wildlife resulting in negative impacts are among the most pressing conservation challenges globally. In regions of smallholder livestock and crop production, interactions with wildlife can compromise human well-being and motivate negative sentiment and retaliation toward wildlife, undermining conservation goals. Although impacts may be unavoidable when human and wildlife land use overlap, scant large-scale human data exist quantifying the direct costs of wildlife to livelihoods. In a landscape of global importance for wildlife conservation in southern Africa, we quantified costs for people living with wildlife through a fundamental measure of human well-being, food security, and we tested whether existing livelihood strategies buffer certain households against crop depredation by wildlife, predominantly elephants. To do this, we estimated Bayesian multilevel statistical models based on multicounty household data (n = 711) and interpreted model results in the context of spatial data from participatory land-use mapping. Reported crop depredation by wildlife was widespread. Over half of the sample households were affected and household food security was reduced significantly (odds ratio 0.37 [0.22, 0.63]). The most food insecure households relied on gathered food sources and welfare programs. In the event of crop depredation by wildlife, these 2 livelihood sources buffered or reduced harmful effects of depredation. The presence of buffering strategies suggests a targeted compensation strategy could benefit the region's most vulnerable people. Such strategies should be combined with dynamic and spatially explicit land-use planning that may reduce the frequency of negative human–wildlife impacts. Quantifying and mitigating the human costs from wildlife are necessary steps in working toward human–wildlife coexistence.     

跨国水资源保护的法律措施——兼及中国的实践

国际流域各国在自己境内利用跨国水资源或进行其他活动时,有义务保护国际流域水资源,防止对其他流域国造成重大损害。对有关国际文件的规定和国际社会的实践进行了系统的分析和比较,从促进跨国水资源包括涉及我国的跨国水资源保护的目的出发,运用比较、概括和归纳的方法,对流域各国保护国际流域水资源的法律措施进行了归纳和总结。这些措施包括但不限于环境影响评价、交流信息、监测、通知、紧急情况下的援助、控制污染、公众参与等。最后就中国促进相关跨国水资源的保护提出了具体的措施建议：严格执行《环境影响评价法》、《水污染防治法》等法律法规;建立跨国河流水环境监测网;保持和加强与相邻国家和沿岸各国的信息交流与合作;继续与更多的沿岸国谈判和签署双边或多边流域保护协议,并建立流域保护或管理委员会负责对跨国河流流域的保护与管理.     

Factors of success and failure for transboundary environmental cooperation: projects in the Gulf of Aqaba

After signing a peace accord in 1994, joint projects were initiated between Israel and Jordan aimed at enhancing environmental protection and resource management. This paper discusses the Red Sea Dead Sea Canal, the Eilat-Aqaba Municipal Cooperation initiative, the Joint Oil Spill Contingency Plan and the Red Sea Marine Peace Park (RSMPP). The latter is an exemplar of transboundary cooperation for planning of a marine protected area and therefore the main case study. Although the RSMPP never fully materialized, analysis of what transpired provides important lessons. We examine what happened in the 20 years since the attempt to establish the RSMPP began and focus on which of its goals were achieved. As a basis for analysis this paper presents factors identified as significant to the success of transboundary protected areas (TBPAs) and uses them to compare the RSMPP to the three other initiatives. In addition to factors reported in the literature that are known to be effective for TBPA success, we found two new factors as most relevant for the RSMPP case: a peripheral geographic location and intensive work among professionals, mostly marine scientists, on the ground operating under a low profile and with limited public attention.