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Library Resource
Artículos de revistas y libros
Diciembre, 2009

The NitroEurope project aims to improve understanding of the nitrogen (N) cycle at the continental scale and quantify the major fluxes of reactive N by a combination of reactive N measurements and modelling activities. As part of the overall measurement strategy, a network of 13 flux 'super sites' (Level-3) has been established, covering European forest, arable, grassland and wetland sites, with the objective of quantifying the N budget at a high spatial resolution and temporal frequency for 4.5 years, and to estimate greenhouse gas budgets (N₂O, CH₄ and CO₂).

Library Resource
Artículos de revistas y libros
Diciembre, 2009
Estados Unidos de América

The central and eastern United States is an important food and timber production region and could potentially be a large-scale carbon sink. These characteristics are functions of the human management of the landscape and favorable soil and climate conditions. Large-scale assessments of carbon uptake and trends in net primary productivity (NPP) have been previously reported for this region using satellite observations, but they cannot quantify the contributions from changes in management and technology independently from climate effects.

Library Resource
Artículos de revistas y libros
Diciembre, 2009
Brasil

Under the Convention on Biological Diversity, the world's governments set a goal of protecting 10% of all ecological regions by 2010. We evaluated progress toward that goal for the world's major terrestrial biomes, realms, and ecoregions. Total land area under any legal protection has increased from previous estimates to 12.9%, a notable achievement, although only 5.8% has strict protection for biodiversity. For biomes, protection ranges from 4% to 25%, with six of 14 biomes still below the 10% level.

Library Resource
Artículos de revistas y libros
Diciembre, 2009
Brasil

The erosion of soil from subsistence agricultures on lands with steep slopes and shallow soil is poorly documented, particularly in Brazil. This paper details the hydrological and soil loss responses to traditional agriculture (shifting agriculture) of a steeply sloped sector (32° incline) classified by FAO has having Regosol soil. This sector is in Guarapuava, Brazil and is covered by a shallow, clayed soil that originates from basalt rock. All measurements were carried out between May 2003 and April 2004.

Library Resource
Artículos de revistas y libros
Diciembre, 2009
China

Runoff in Haihe River Catchment of China is steadily declining due to climate change and human activity. Determining abrupt changes in runoff could enhance identification of the main driving factors for the sudden changes. In this study, the sequential Mann-Kendall test analysis is used to determine abrupt changes in runoff in eight sub-catchments of Haihe River Catchment, while trend analysis via the traditional Mann-Kendall test for the period 1960-1999 is used to identify the basic trend of precipitation and runoff.

Library Resource
Artículos de revistas y libros
Diciembre, 2009

Soil biota drive fundamental ecosystem processes such as decomposition, nutrient cycling, and maintenance of soil structure. They are especially active in grassland ecosystems such as the tallgrass prairie, where much of the net primary productivity is allocated belowground and ultimately processed by heterotrophic soil organisms.

Library Resource
Artículos de revistas y libros
Diciembre, 2009
China

The concept of critical nutrient amounts (CNA) for a watershed was developed to address eutrophication in surface waters from diffuse (non-point) source pollution. CNA is defined as the maximum allowable applied or generated amount (AGA) of a nutrient from natural and human sources that can be emitted and still allow compliance with water quality standards.

Library Resource
Artículos de revistas y libros
Diciembre, 2009

Communal forests, or Montes Veciñais en Man Común (MVMC), are a specific form of communal land tenure and a singular legal category in Galicia, a region in Northwest Spain. MVMC extend over one third of the area of the region. Over the years, MVMC have undergone many changes in terms of ownership and resource management. Such changes have resulted in land tenure insecurity among current landowners, who live in rural areas.

Library Resource
Artículos de revistas y libros
Diciembre, 2009

The loss of soil and carbon (C) from erosional processes is of greater importance to agricultural productivity and sustainable resource management. Land management practices influence structural properties of soil aggregates, its size and stability, and the stabilization effect of soil organic carbon (SOC), and other cementing agents. Water erosion affects all these properties and consequently decreases productivity of land. Thus, relative significance of loss of soil and C from dry and wet aggregates was studied from soil sampled from the North Appalachian Experimental Watersheds (NAWEP).

Library Resource
Artículos de revistas y libros
Diciembre, 2009

The response of orthopteran communities to abandonment of extensively managed hay meadows was investigated in an Alpine region. Fifty-five sites in four different successional stages were sampled: (i) mown meadows, (ii) young abandoned meadows, (iii) old abandoned meadows, and (iv) young forests. Mown meadows and young abandoned meadows (3-5 years since the last cut) had the highest, young forests the lowest mean number of orthopteran species.

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