Archive for the ‘ecology’ Category

Effects of Climate Variability and Accelerated Forest Thinning on Watershed-Scale Runoff in Southwestern USA Ponderosa Pine Forests

December 1, 2014 Comments off

Effects of Climate Variability and Accelerated Forest Thinning on Watershed-Scale Runoff in Southwestern USA Ponderosa Pine Forests
Source: PLoS ONE

The recent mortality of up to 20% of forests and woodlands in the southwestern United States, along with declining stream flows and projected future water shortages, heightens the need to understand how management practices can enhance forest resilience and functioning under unprecedented scales of drought and wildfire. To address this challenge, a combination of mechanical thinning and fire treatments are planned for 238,000 hectares (588,000 acres) of ponderosa pine (Pinus ponderosa) forests across central Arizona, USA. Mechanical thinning can increase runoff at fine scales, as well as reduce fire risk and tree water stress during drought, but the effects of this practice have not been studied at scales commensurate with recent forest disturbances or under a highly variable climate. Modifying a historical runoff model, we constructed scenarios to estimate increases in runoff from thinning ponderosa pine at the landscape and watershed scales based on driving variables: pace, extent and intensity of forest treatments and variability in winter precipitation. We found that runoff on thinned forests was about 20% greater than unthinned forests, regardless of whether treatments occurred in a drought or pluvial period. The magnitude of this increase is similar to observed declines in snowpack for the region, suggesting that accelerated thinning may lessen runoff losses due to warming effects. Gains in runoff were temporary (six years after treatment) and modest when compared to mean annual runoff from the study watersheds (0–3%). Nonetheless gains observed during drought periods could play a role in augmenting river flows on a seasonal basis, improving conditions for water-dependent natural resources, as well as benefit water supplies for downstream communities. Results of this study and others suggest that accelerated forest thinning at large scales could improve the water balance and resilience of forests and sustain the ecosystem services they provide.

Urban Computing: Concepts, Methodologies, and Applications

November 10, 2014 Comments off

Urban Computing: Concepts, Methodologies, and Applications
Source: Microsoft Research

Urbanization’s rapid progress has modernized many people’s lives, and also engendered big issues, such as traffic congestion, energy consumption, and pollution. Urban computing aims to tackle these issues by using the data that has been generated in cities, e.g., traffic flow, human mobility and geographical data. Urban computing connects urban sensing, data management, data analytics, and service providing into a recurrent process for an unobtrusive and continuous improvement of people’s lives, city operation systems, and the environment. Urban computing is an interdisciplinary field where computer sciences meet conventional city-related fields, like transportation, civil engineering, environment, economy, ecology, and sociology, in the context of urban spaces. This article first introduces the concept of urban computing, discussing its general framework and key challenges from the perspective of computer sciences. Secondly, we classify the applications of urban computing into seven categories, consisting of urban planning, transportation, the environment, energy, social, economy, and public safety & security, presenting representative scenarios in each category. Thirdly, we summarize the typical technologies that are needed in urban computing into four folds, which are about urban sensing, urban data management, knowledge fusion across heterogeneous data, and urban data visualization. Finally, we outlook the future of urban computing, suggesting a few research topics that are somehow missing in the community.

The Modern Outback: Nature, people and the future of remote Australia

October 23, 2014 Comments off

The Modern Outback: Nature, people and the future of remote Australia
Source: Pew Charitable Trusts

The Outback is the vast heartland of Australia. It includes places of exquisite beauty and wildness. It is an area of extremes, alternately lush and bountiful, harsh and inhospitable. The people and land of the Outback embody much that is most distinctive and characteristic of Australia. Yet while the Outback is quintessentially Australian, it is also a place of international consequence.

The Outback has deeply interconnected threads of people and landscapes. Its natural environments support people, jobs, and economies, as well as some of the world’s most diverse and unusual plants and animals. The Outback’s environmental values merit the attention and concern of the nation and the world. However, some of these values are being lost, diminished, or degraded because of particular threats. Managing these risks more effectively, or removing them entirely, would allow for significant progress in ongoing efforts to maintain the environmental, natural and cultural values of the Australian continent as a whole.

Pollution from drug manufacturing: review and perspectives

October 16, 2014 Comments off

Pollution from drug manufacturing: review and perspectives
Source: Philosophical Transactions of the Royal Society

As long ago as the sixteenth century, Paracelsus recognized that ‘the dose makes the poison’. Indeed, environmental concentrations of pharmaceuticals excreted by humans are limited, most importantly because a defined dose is given to just a fraction of the population. By contrast, recent studies have identified direct emission from drug manufacturing as a source of much higher environmental discharges that, in some cases, greatly exceed toxic threshold concentrations. Because production is concentrated in specific locations, the risks are not linked to usage patterns. Furthermore, as the drugs are not consumed, metabolism in the human body does not reduce concentrations. The environmental risks associated with manufacturing therefore comprise a different, wider set of pharmaceuticals compared with those associated with risks from excretion. Although pollution from manufacturing is less widespread, discharges that promote the development of drug-resistant microorganisms can still have global consequences. Risk management also differs between production and excretion in terms of accountability, incentive creation, legal opportunities, substitution possibilities and costs. Herein, I review studies about industrial emissions of pharmaceuticals and the effects associated with exposure to such effluents. I contrast environmental pollution due to manufacturing with that due to excretion in terms of their risks and management and highlight some recent initiatives.

See also:
+ Detection and drivers of exposure and effects of pharmaceuticals in higher vertebrates
+ Risks of hormonally active pharmaceuticals to amphibians: a growing concern regarding progestagens
+ Putting pharmaceuticals into the wider context of challenges to fish populations in rivers

Casting the Net: A More Efficient Approach to U.S. Fisheries Management

October 6, 2014 Comments off

Casting the Net: A More Efficient Approach to U.S. Fisheries Management
Source: Hamilton Project (Brookings Institution)

The fishing industry contributes about $90 billion annually to the U.S. economy, through commercial fishing, charter boat companies, manufacturers of fishing equipment, and more. This translates into over one and a half million jobs for American workers. In many cases, however, current management practices lead to inefficient fishing practices that threaten both the ecological and economic sustainability of U.S. fisheries.

On September 10th, The Hamilton Project hosted a forum to discuss new opportunities for improving the economic prosperity and long-term sustainability of the U.S. fishing industry. The forum opened with remarks by former U.S. Treasury Secretary Robert E. Rubin.

The Project released an economic overview of the U.S. fishing industry, and a new paper by economist Christopher Costello of UC Santa Barbara proposing amendments to the Magnuson-Stevens Fishery Conservation and Management Act requiring that fisheries meeting certain criteria be required to undertake a comparison of the economic, social, and ecological trade-offs between status quo management and alternative management structures, including catch shares.

Living Planet Report 2014

October 2, 2014 Comments off

Living Planet Report 2014
Source: World Wildlife Fund

The Living Planet Report documents the state of the planet—including biodiversity, ecosystems, and demand on natural resources—and what this means for humans and wildlife. Published by WWF every two years, the report brings together a variety of research to provide a comprehensive view of the health of the earth.

Population sizes of vertebrate species—mammals, birds, reptiles, amphibians, and fish—have declined by 52 percent over the last 40 years. In other words, those populations around the globe have dropped by more than half in fewer than two human generations.

At the same time, our own demands on nature are unsustainable and increasing. We need 1.5 Earths to regenerate the natural resources we currently use; we cut trees faster than they mature, harvest more fish than oceans replenish, and emit more carbon into the atmosphere than forests and oceans can absorb.

A Century of Ocean Warming on Florida Keys Coral Reefs: Historic In Situ Observations

October 1, 2014 Comments off

A Century of Ocean Warming on Florida Keys Coral Reefs: Historic In Situ Observations
Source: Estuaries and Coasts

There is strong evidence that global climate change over the last several decades has caused shifts in species distributions, species extinctions, and alterations in the functioning of ecosystems. However, because of high variability on short (i.e., diurnal, seasonal, and annual) timescales as well as the recency of a comprehensive instrumental record, it is difficult to detect or provide evidence for long-term, site-specific trends in ocean temperature. Here we analyze five in situ datasets from Florida Keys coral reef habitats, including historic measurements taken by lighthouse keepers, to provide three independent lines of evidence supporting approximately 0.8 °C of warming in sea surface temperature (SST) over the last century. Results indicate that the warming observed in the records between 1878 and 2012 can be fully accounted for by the warming observed in recent decades (from 1975 to 2007), documented using in situ thermographs on a mid-shore patch reef. The magnitude of warming revealed here is similar to that found in other SST datasets from the region and to that observed in global mean surface temperature. The geologic context and significance of recent ocean warming to coral growth and population dynamics are discussed, as is the future prognosis for the Florida reef tract.


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