The San Pedro River (SPR) is located in northern Sonora (Mexico) and southeastern Arizona (USA). SPR is a transboundary river
that develops along the Sonora (Mexico) and Arizona (USA) border, and is considered the main source of water for a variety
of users (human settlements, agriculture, livestock, and industry). The SPR originates in the historic Cananea mining area,
which hosts some of the most important copper mineralizations in Mexico. Acid mine drainage derived from mine tailings is
currently reaching a tributary of the SPR near Cananea City, resulting in the contamination of the SPR with heavy metals and
sulfates in water and sediments. This study documents the accumulation and distribution of heavy metals in surface water along
a segment of the SPR from 1993 to 2005. Total concentrations of Cd, Cu, Fe, Mn, Pb, and Zn in surface waters are above maximum
permissible levels in sampling sites near mine tailing deposits. Nevertheless, a significant decrease in the Fe and SO42− in surface water (SO42−: 7,180–460.39 mg/L; Fe: 1,600–9.51 mg/L) as well as a gradual decrease in the heavy and transition metal content were observed
during the period from 1994 to 2005. Approximately 2.3 km downstream of the mine tailings, the heavy metal content of the
water drops quickly following an increase in pH values due to the discharging of wastewater into the river. The attenuation
of the heavy metal content in surface waters is related to stream sediment precipitation (accompanied by metal coprecipitation
and sorption) and water dilution. Determining the heavy metal concentration led to the conclusion that the Cananea mining
area and the San Pedro River are ecosystems that are impacted by the mining industry and by untreated wastewater discharges
arising from the city of Cananea (Sonora, Mexico). 相似文献
Individual action and support for policy to tackle climate change have been linked to perceptions of political and scientific controversy and consensus concerning the issue. Recent media effects research indicates that presentation of agreement or conflict between actors’ opinions influences how audiences respond to news about climate change and policy. While some national case studies have investigated portrayals of actors’ positions on important questions regarding climate change in the media, they are largely absent from comparative research. This study addresses this gap by analysing portrayals of actor-issue-positions and the emerging patterns of controversy and consensus in German, Canadian, and US coverage. Studying a sample of occurrences of climate change-related issues (N = 902) in-depth, the results show German media present political consensus about the need to limit emissions and societal controversy about the efficacy of specific mitigation measures. Presenting mainly consensus, Canadian media report more on climate change’s impact, leaving aside the issue of efficacy. In the US, media emphasise political controversy — about the need to limit emissions and occasionally about climate change’s impact on humans. The findings, consistent with other recent publications, can best be explained by journalists selectively indexing of seemingly relevant actor-issue-positions. 相似文献
Across the rural American West, the restructuring of rural capitalism has transformed production landscapes into those increasingly structured by the development and consumption of natural and cultural amenities. This project used principles from symbolic interactionism, ethnographic methods, and the analytical framework of regional political ecology to understand the role of environmental learning in negotiating the new management regime associated with amenity-based capitalism in rural Fremont County, Colorado. The study found that most amenity residents participate regularly in social learning about the environment through a variety of interpersonal and organizational behaviors. In addition, they are responding collectively to environmental risks and opportunities associated with wildfire, noxious weeds and invasive grass species, prospective uranium mining, and restoration of cultural-landscape features. Ultimately, the practices of environmental learning concern how private properties and assets will be managed relative to the social construction of the environment as an amenity for personal consumption. Conservation and management prospects in this and other rural areas in the postindustrial world can be enhanced by understanding the microsociology of exurban geographies and by engaging the social forms and processes related to this distinctive landscape construction. 相似文献
The institutions, practices, and discourses of US development policy and foreign assistance are undergoing profound changes. Central to these has been the creation of a new framework for foreign aid, built around a complex taxonomy of developing states and governance issue areas, with geographic and governance categories predicated on notions of state stability and fragility, strategic geopolitical position, and development progress. Given its long-standing position as the primary federal agency responsible for development and foreign aid, the US Agency for International Development (USAID) has played an important role in these policy changes, even as its political status and standing have suffered in recent years. The new framework is beset by contradictions, stemming both from the problematic relationship between development, security, and liberalization in agency rhetoric and strategies, and from intensive restructuring processes affecting USAID’s internal character and external relations. This paper investigates the new framework for foreign aid, linking internal restructuring at USAID to broader trends in state development strategies. I argue that shifts in US development and aid policy - toward emphases on “transformational development” abroad and centralization over strategic decision making domestically, crystallized in the new framework - are based in contradictory understandings of aid deservedness that stem from the tensions between economic and geopolitical aims within the current security-focused US state project of neoliberalization. These contradictions and tensions are displaced onto USAID via the Foreign Assistance Framework. 相似文献
The issue of US ratification of international environmental treaties is a recurring obstacle for environmental multilateralism, including the climate regime. Despite the perceived importance of the role of the US to the success of any future international climate agreement, there has been little direct coverage in terms of how an effective agreement can specifically address US legal participation. This article explores potential ways of allowing for US legal participation in an effective climate treaty. Possible routes forward include the use of domestic legislation such as section 115 (S115) of the Clean Air Act (CAA) and the use of sole–executive agreements, instead of Senate ratification. Legal participation from the US through sole–executive agreements is possible if the international architecture is designed to allow for their use. Architectural elements such as varying legality and participation across an agreement (variable geometry) could allow for the use of sole–executive agreements. Two broader models for a 2015 agreement with legal participation through sole–executive agreements are constructed based upon these options: a modified pledge and review system and a form of variable geometry composed of number of opt-out, voting-based protocols on specific issues accompanied by bilateral agreements on mitigation commitments with other major emitters through the use of S115 and sole–executive agreements under the Montreal Protocol and Chicago Convention (‘Critical Mass Governance'). While there is no single solution, Critical Mass Governance appears to provide the optimum combination of tools to effectively allow for US legal participation whilst ensuring an effective treaty.
Policy relevance
This article provides some recommendations on how to create an effective, legally binding treaty that allow for US legal participation without Senate approval. Given the recent election of a Republican majority in the US Senate and Congress, increasing willingness of the President to utilize his executive powers, as well as a strong shift in negotiations to appease US interests, the insights of this research are timely and relevant to delegations and other United Nations Framework Convention on Climate Change (UNFCCC) actors. It will also be of use to domestic US actors involved with climate policy by illustrating how to allow for effective and sustainable US multilateral engagement that bypasses domestic political gridlock. 相似文献
In the United States, desalination has considerably expanded since the 1950s, reaching a daily production capacity of 2 BGD (billion gallons per day) with around 1336 operating plants as of 2013 (GWI, 2013). Despite this continuous growth, a steady increase in desalination investments and growing demand for water, research on geospatial representation of desalination plants and their characteristics over time does not exist or is very limited. This paper aims at filling this gap by developing interactive 5D and 6D geospatial models and a multi-dimensional analysis of desalination trends in the time span 1950–2013. The analysis shows that desalination plants are located mainly on the East and West Coast of the United States, with Florida, California, and Texas leading in the national desalination sector. Despite the geographical proximity to the sea, most of the plants use brackish groundwater due to economic factors related to the desalination process itself and the disposal of the highly saline byproduct – brine. The models can be used both for educational and interdisciplinary research purposes and help with determining socio-economic viability of establishing prospective desalination plants in different regions in the future. They can also help support decision makers in solving emergency questions related to water shortages and preparing for long-term water scarcity in different US regions. 相似文献
Military activities have produced contaminated environments at many sites around the world. This contamination and the associated
health risks play a large role in how these places can be redeveloped after military use. In this essay we focus on the island
of Vieques, Puerto Rico which was used as a bombing range by the US military for six decades until 2003. We examine the ways
different groups of people perceive this formerly militarized landscape and the ways that these perceptions legitimatize certain
redevelopment options over others. Through participant observation, semi-structured interviews and an analysis of textual
materials we found that many local residents view the island as suffering from severe contamination while the large number
of visitors, tourism promoters and North Americans now flocking to the post-militarized Vieques view it quite differently.
These perceptions of purity and contamination, affected by different knowledges of the island’s history, have led to differing
valuation of the landscape and contentious economic, political, and cultural battles over an island often labeled “natural”
despite a history of military use and social exclusion.