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Volume 1: \"The Earth's oceans are currently undergoing unprecedented changes: rivers have suffered a severe reduction in their sediment transport, and as a result, sediment input to the oceans has dropped lower than ever before. These inputs have varied over millennia as a result of both natural occurrences and human actions, such as the building of dams and the extraction of materials from riverbeds. Sedimentary Crisis at the Global Scale 1 examines how river basins have been affected by the sedimentary crises of various historical epochs. By studying global balances, it provides insights into the profound disruption of the solid transport of fluvial bodies. The book also explores studies of various rivers, from the Amazon, which remains relatively unaffected, to dying rivers such as the Colorado and the Nile.\" -- Back cover.

An ecosystem in freefall, a shrinking water supply for cities and agriculture, an antiquated network of failure-prone levees—this is the Sacramento-San Joaquin Delta, the major hub of California's water system. Written by a team of independent water experts, this analysis of the latest data evaluates proposed solutions to the Delta's myriad problems. Through in-depth economic and ecological analysis, the authors find that the current policy of channeling water exports through the Delta is not sustainable for any interest. Employing a peripheral canal-conveying water around the Delta instead of through it—as part of a larger habitat and water management plan appears to be the best strategy to maintain both a high-quality water supply and at the same time improve conditions for native fish and wildlife. This important assessment includes integrated analysis of long term ecosystem and water management options and demonstrates how issues such as climate change and sustainability will shape the future. Published in cooperation with the Public Policy Institute of California

Winner of the 2012 George Perkins Marsh Prize for Best Book in Environmental History In the twentieth century, the Mekong Delta has emerged as one of Vietnam s most important economic regions. Its swamps, marshes, creeks, and canals have played a major role in Vietnam s turbulent past, from the struggles of colonialism to the Cold War and the present day. Quagmire considers these struggles, their antecedents, and their legacies through the lens of environmental history. Beginning with the French conquest in the 1860s, colonial reclamation schemes and pacification efforts centered on the development of a dense network of new canals to open land for agriculture. These projects helped precipitate economic and environmental crises in the 1930s, and subsequent struggles after 1945 led to the balkanization of the delta into a patchwork of regions controlled by the Viet Minh, paramilitary religious sects, and the struggling Franco-Vietnamese government. After 1954, new settlements were built with American funds and equipment in a crash program intended to solve continuing economic and environmental problems. Finally, the American military collapse in Vietnam is revealed as not simply a failure of policy makers but also a failure to understand the historical, political, and environmental complexity of the spaces American troops attempted to occupy and control. By exploring the delta as a quagmire in both natural and political terms, Biggs shows how engineered transformations of the Mekong Delta landscape - channelized rivers, a complex canal system, hydropower development, deforestation - have interacted with equally complex transformations in the geopolitics of the region. Quagmire delves beyond common stereotypes to present an intricate, rich history that shows how closely political and ecological issues are intertwined in the human interactions with the water environment in the Mekong Delta. Watch the book trailer: https://www.youtube.com/watch?v=gp1-UItZqsk Winner of the 2012 George Perkins Marsh Prize for Best Book in Environmental History In the twentieth century, the Mekong Delta has emerged as one of Vietnam s most important economic regions. Its swamps, marshes, creeks, and canals have played a major role in Vietnam s turbulent past, from the struggles of colonialism to the Cold War and the present day. Quagmire considers these struggles, their antecedents, and their legacies through the lens of environmental history. Beginning with the French conquest in the 1860s, colonial reclamation schemes and pacification efforts centered on the development of a dense network of new canals to open land for agriculture. These projects helped precipitate economic and environmental crises in the 1930s, and subsequent struggles after 1945 led to the balkanization of the delta into a patchwork of regions controlled by the Viet Minh, paramilitary religious sects, and the struggling Franco-Vietnamese government. After 1954, new settlements were built with American funds and equipment in a crash program intended to solve continuing economic and environmental problems. Finally, the American military collapse in Vietnam is revealed as not simply a failure of policy makers but also a failure to understand the historical, political, and environmental complexity of the spaces American troops attempted to occupy and control. By exploring the delta as a quagmire in both natural and political terms, Biggs shows how engineered transformations of the Mekong Delta landscape - channelized rivers, a complex canal system, hydropower development, deforestation - have interacted with equally complex transformations in the geopolitics of the region. Quagmire delves beyond common stereotypes to present an intricate, rich history that shows how closely political and ecological issues are intertwined in the human interactions with the water environment in the Mekong Delta. Watch the book trailer: http://www.youtube.com/user/UWashingtonPress#p/u/2/gp1-UItZqsk

This Delta, This Land is a comprehensive environmental history of the Yazoo-Mississippi Delta--the first one to place the Delta's economic and cultural history in an environmental context. The Delta, the floodplain between two great rivers in the northwestern corner of Mississippi, has changed enormously since the Civil War. Agriculture, lumbering, and flood-management schemes have transformed it beyond recognition--and beyond any prospects for a full recovery. However, says Mikko Saikku, the 150 years following the Civil War brought greater environmental change than we generally realize. Indeed, the long-term environmental history of the Delta is much more complex than our current view of it, which privileges recent periods rather than presenting the entire continuum. Looking across thousands of years, Saikku examines successive human societies in the Delta, drawing connections between environmental and social problems and noting differences between Native Americans and Euro-Americans in their economies, modes of production, and land-use patterns. Saikku's range of sources is astonishing: travel literature, naturalists' writings, government records, company archives, archaeological data, private correspondence, and more. As he documents how such factors as climate and water levels shaped the Delta, he also reveals the human aspects of the region's natural history, including land reclamation, slave and sharecropper economies, ethnic and racial perceptions of land ownership and stewardship, and even blues music.

The world’s river deltas are increasingly vulnerable due to pressures from human activities and environmental change. In deltaic regions, the distribution of salinity controls the resourcing of fresh water for agriculture, aquaculture and human consumption; it also regulates the functioning of critical natural habitats. Despite numerous insightful studies, there are still significant uncertainties on the spatio-temporal patterns of salinity across deltaic systems. In particular, there is a need for a better understanding of the salinity distribution across deltas’ channels and for simple predictive relationships linking salinity to deltas’ characteristics and environmental conditions. We address this gap through idealized three-dimensional modelling of a typical river-dominated delta configuration and by investigating the relationship between salinity, river discharge and channels’ bifurcation order. Model results are then compared with real data from the Mississippi River Delta. Results demonstrate the existence of simple one-dimensional and analytical relationships describing the salinity field in a delta. Salinity and river discharge are exponentially and negatively correlated. The Strahler-Horton method for stream labelling of the delta channels was implemented. It was discovered that salinity increases with decreasing stream order. These useful relationships between salinity and deltas’ bulk features and geometry might be applied to real case scenarios to support the investigation of deltas vulnerability to environmental change and the management of deltaic ecosystems.

Regional air pollution is significantly associated with dominant weather systems. In this study, the relationship between the particle pollution over the Yangtze River Delta (YRD) region and weather patterns is investigated. First, the pollution characteristics of particles in the YRD are studied using in situ monitoring data (PM2.5 and PM10) in 16 cities and Terra/MODIS AOD (aerosol optical depth) products collected from December 2013 to November 2014. The results show that the regional mean value of AOD is high in the YRD, with an annual mean value of 0.71±0.57. The annual mean particle concentrations in the cities of Jiangsu Province all exceed the national air quality standard. The pollution level is higher in inland areas, and the highest concentrations of PM2.5 and PM10 are 79 and 130 µg m−3, respectively, in Nanjing. The PM2.5  :  PM10 ratios are typically high, thus indicating that PM2.5 is the overwhelmingly dominant particle pollutant in the YRD. The wintertime peak of particle concentrations is tightly linked to the increased emissions during the heating season as well as adverse meteorological conditions. Second, based on NCEP (National Center for Environmental Prediction) reanalysis data, synoptic weather classification is conducted and five typical synoptic patterns are objectively identified. Finally, the synthetic analysis of meteorological fields and backward trajectories are applied to further clarify how these patterns impact particle concentrations. It is demonstrated that air pollution is more or less influenced by high-pressure systems. The relative position of the YRD to the anti-cyclonic circulation exerts significant effects on the air quality of the YRD. The YRD is largely influenced by polluted air masses from the northern and the southern inland areas when it is located at the rear of the East Asian major trough. The significant downward motion of air masses results in stable weather conditions, thereby hindering the diffusion of air pollutants. Thus, this pattern is quite favorable for the accumulation of pollutants in the YRD, resulting in higher regional mean PM10 (116.5 ± 66.9 µg m−3), PM2.5 (75.9 ± 49.9 µg m−3), and AOD (0.74) values. Moreover, this pattern is also responsible for the occurrence of most large-scale regional PM2.5 (70.4 %) and PM10 (78.3 %) pollution episodes. High wind speed and clean marine air masses may also play important roles in the mitigation of pollution in the YRD. Especially when the clean marine air masses account for a large proportion of all trajectories (i.e., when the YRD is affected by the cyclonic system or oceanic circulation), the air in the YRD has a lesser chance of being polluted. The observed correlation between weather patterns and particle pollution can provide valuable insight into making decisions about pollution control and mitigation strategies.

An intimate glimpse into the microcosmic world of \"hybrid landscapes\" and their inhabitants. With this book, Kuntala Lahiri-Dutt and Gopa Samanta offer an intimate glimpse into the microcosmic world of \"hybrid environments.\" Focusing on chars -- the part-land, part-water, low-lying sandy masses that exist within the riverbeds in the floodplains of lower Bengal -- the authors show how, both as real-life examples and as metaphors, chars straddle the conventional categories of land and water, and how people who live on them fluctuate between legitimacy and illegitimacy. The result, a study of human habitation in the nebulous space between land and water, charts a new way of thinking about land, people, and people's ways of life. Kuntala Lahiri-Dutt is a senior fellow in resource management in the Asia-Pacific Program at the College of Asia and the Pacific at the Australian National University. She lives in Canberra. Gopa Samanta is an associate professor in geography at the University of Burdwan. She lives in Golapbag, Burdwan, India.

A regional fully coupled meteorology–chemistry model, Weather Research and Forecasting model with Chemistry (WRF-Chem), was employed to study the seasonality of ozone (O3) pollution and its sources in both China and India. Observations and model results suggest that O3 in the North China Plain (NCP), Yangtze River Delta (YRD), Pearl River Delta (PRD), and India exhibit distinctive seasonal features, which are linked to the influence of summer monsoons. Through a factor separation approach, we examined the sensitivity of O3 to individual anthropogenic, biogenic, and biomass burning emissions. We found that summer O3 formation in China is more sensitive to industrial and biogenic sources than to other source sectors, while the transportation and biogenic sources are more important in all seasons for India. Tagged simulations suggest that local sources play an important role in the formation of the summer O3 peak in the NCP, but sources from Northwest China should not be neglected to control summer O3 in the NCP. For the YRD region, prevailing winds and cleaner air from the ocean in summer lead to reduced transport from polluted regions, and the major source region in addition to local sources is Southeast China. For the PRD region, the upwind region is replaced by contributions from polluted PRD as autumn approaches, leading to an autumn peak. The major upwind regions in autumn for the PRD are YRD (11 %) and Southeast China (10 %). For India, sources in North India are more important than sources in the south. These analyses emphasize the relative importance of source sectors and regions as they change with seasons, providing important implications for O3 control strategies.

The study shows extensive oil contamination of rivers, creeks, and ground waters in Ogoniland, Nigeria. The levels found in the more contaminated sites are high enough to cause severe impacts on the ecosystem and human health: extractable petroleum hydrocarbons (EPHs) (>10-C40) in surface waters up to 7420 μg L⁻¹, drinking water wells show up to 42 200 μg L⁻¹, and benzene up to 9000 μg L⁻¹, more than 900 times the WHO guidelines. EPH concentrations in sediments were up to 17 900 mg kg⁻¹. Polycyclic aromatic hydrocarbons concentrations reached 8.0 mg kg⁻¹, in the most contaminated sites. The contamination has killed large areas of mangroves. Although the natural conditions for degradation of petroleum hydrocarbons are favorable with high temperatures and relatively high rainfall, the recovery of contaminated areas is prevented due to the chronic character of the contamination. Oil spills of varying magnitude originates from facilities and pipelines; leaks from aging, dilapidated, and abandoned infrastructure; and from spills during transport and artisanal refining of stolen oil under very primitive conditions.

Background: The occurrence of halogenated analogs of the xenoestrogen bisphenol A (BPA) has been recently demonstrated both in environmental and human samples. These analogs include brominated [e.g., tetrabromobisphenol A (TBBPA)] and chlorinated [e.g., tetrachlorobisphenol A (TCBPA) bisphenols, which are both flame retardants. Because of their structural homology with BPA, such chemicals are candidate endocrine disruptors. However, their possible target(s) within the nuclear hormone receptor superfamily has remained unknown. Objectives: We investigated whether BPA and its halogenated analogs could be ligands of estrogen receptors (ERs) and peroxisome proliferator-activated receptors (PPARs) and act as endocrine-disrupting chemicals. Methods: We studied the activity of compounds using reporter cell lines expressing ERs and PPARs. We measured the binding affinities to PPARγ by competitive binding assays with [³H]-rosiglitazone and investigated the impact of TBBPA and TCBPA on adipocyte differentiation using NIH3T3-L1 cells. Finally, we determined the binding mode of halogenated BPAs to PPARγ by X-ray crystallography. Results: We observed that TBBPA and TCBPA are human, zebrafish, and Xenopus PPARγ ligands and determined the mechanism by which these chemicals bind to and activate PPARγ. We also found evidence that activation of ERα, ERß, and PPARγ depends on the degree of halogenation in BPA analogs. We observed that the bulkier brominated BPA analogs, the greater their capability to activate PPARγ and the weaker their estrogenic potential. Conclusions: Our results strongly suggest that polyhalogenated bisphenols could function as obesogens by acting as agonists to disrupt physiological functions regulated by human or animal PPARγ.