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Effects of groundwater level variations on the nitrate content of groundwater: a case study in Luoyang area, China

Journal Articles & Books
Dezembro, 2015
China

Most researchers usually adopt laboratory experimental methods when studying the effects of water level variations on the concentrations of pollutants. In this study, the data from routine monitoring sites in the city of Luoyang, China, are collected and analyzed to verify the results of previous laboratory experiments and to examine whether variations in the water level affect the concentration of pollutants in different locations, particularly that of nitrates. Statistical studies conducted between 2007 and 2011 show a significant variation in the groundwater depth in the Luoyang area.

Impact of three decades of urban growth on soil resources in Elche (Alicante, Spain) Impacto en el suelo como recurso depués de tres décadas de crecimiento urbano en Elche (Alicante, España) Impacto sobre o recurso solo após três décadas de crescimento...

Journal Articles & Books
Março, 2012
Espanha

This article analyses the impact of soil sealing associated with three decades of urban growth in the Mediterranean coastal municipality of Elche (Alicante, Spain) on local soil resources. Geographical Information System (GIS) and remote sensing (RS) techniques were used to obtain and analyse different types of thematic information relating to urban growth and soil resources (soil class, land use capability, and physiographic classes).

paradox of keystone species persecuted as pests: A call for the conservation of abundant small mammals in their native range

Journal Articles & Books
Dezembro, 2011

Small mammals, such as European rabbits (Oryctolagus cuniculus), plateau pikas (Ochotona curzoniae) and prairie dogs (Cynomys spp.), traditionally have been perceived as pests and targeted for control within their native ranges, where they perform essential ecosystem roles and are considered keystone species. These species can reach high densities, and have been subjected to eradication campaigns because of their putative negative impact on natural habitats and agriculture and their competition with livestock for forage.

Potential and sustainability for carbon sequestration with improved soil management in agricultural soils of China

Journal Articles & Books
Dezembro, 2007
China

Arable land soils generally have lower organic carbon (C) levels than soils under native vegetation; increasing the C stocks through improved management is suggested as an effective means to sequester CO2 from the atmosphere. China's arable lands, accounting for 13% of the world's total, play an important role in soil C sequestration, but their potential to enhance C sequestration has not yet been quantitatively assessed.

Performance of the SWEEP model affected by estimates of threshold friction velocity

Journal Articles & Books
Dezembro, 2014

The Wind Erosion Prediction System (WEPS) is a process-based model and needs to be verified under a broad range of climates, soils, and land management practices. Occasional poor performance of the WEPS erosion submodel (Single-event Wind Erosion Evaluation Program, or SWEEP) in simulating small amounts of erosion of loessial soils, which contribute to poor air quality in the Columbia Plateau region of the U.S. Pacific Northwest, has been partly attributed to overestimation of threshold friction velocity (u*t).

Structural Conservation Practices in US Wheat Production: A Cost-Function Technology Adoption Approach

Journal Articles & Books
Dezembro, 2009

Based on 2004 CEAP-ARMS Phase II data, higher-sales farms not participating in a conservation programme adopted farmland conservation structures much more intensively on wheat fields than did any other farm-size type among conservation programme participants or non-participants. Survey results suggest that wheat farms not participating in a conservation programme more frequently adopted infield conservation structures, while conservation programme participants more often installed field perimeter conservation structures.

Assessment of local land and water institutions in the Blue Nile and their impact on environmental management

Conference Papers & Reports
Novembro, 2009
Etiópia

Land and water institutions play a vital role in managing and sustaining land and water resources as well as enhancing economic development and poverty alleviation efforts. While a lot has been done in terms of understanding the micro-determinants of farmers decisions in land and water conservation, there is little attempt to understand the broad macro-institutional and organizational issues that influence land and water management decisions.

Assessment of Total Maximum Daily Load Implementation Strategies for Nitrate Impairment of the Raccoon River, Iowa

Journal Articles & Books
Dezembro, 2010

The state of Iowa requires developing total maximum daily loads (TMDLs) for over 400 water bodies that are listed on the 303(d) list of the impaired waters. The Raccoon River watershed, which covers approximately 9400 km2 of prime agriculture land and represents a typical Midwestern corn-belt region in west-central Iowa, was found to have three stream segments impaired by nitrate-N. The Soil and Water Assessment Tool (SWAT) was applied to this watershed to facilitate the development of a TMDL.

GIS based MCE model for identifying water colour generation potential in UK upland drinking water supply catchments

Journal Articles & Books
Dezembro, 2012

Water discolouration is one of the key water quality problems faced by UK water companies taking raw water from peatland catchments. A water colour model has been developed using a combined Geographical Information System and Multicriteria Evaluation approach. The model was used to predict water colour production potential based on key land management practices controlling colour production in UK upland catchments.

Combining LiDAR and IKONOS Data for Eco-Hydrological Classification of an Ombrotrophic Peatland

Journal Articles & Books
Dezembro, 2010

Remote sensing techniques have potential for peatland monitoring, but most previous work has focused on spectral approaches that often result in poor discrimination of cover types and neglect structural information. Peatlands contain structural "microtopes" (e.g., hummocks and hollows) which are linked to hydrology, biodiversity and carbon sequestration, and information on surface structure is thus a useful proxy for peatland condition.

Amphibian Responses to Wildfire in the Western United States: Emerging Patterns from Short-Term Studies

Journal Articles & Books
Dezembro, 2011
Estados Unidos

The increased frequency and severity of large wildfires in the western United States is an important ecological and management issue with direct relevance to amphibian conservation. Although the knowledge of fire effects on amphibians in the region is still limited relative to most other vertebrate species, we reviewed the current literature to determine if there are evident patterns that might be informative for conservation or management strategies.