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There are 2, 239 content items of different types and languages related to cobertura de suelos on the Land Portal.

cobertura de suelos

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Long-term water balance and conceptual model of a semi-arid mountainous catchment

Journal Articles & Books
Diciembre, 2011
Estados Unidos de América

Long-term water balance investigations are needed to better understand hydrologic systems, especially semi-arid mountainous catchments. These systems exhibit considerable interannual variability in precipitation as well as spatial variation in snow accumulation, soils, and vegetation. This study extended a previous 10-year water balance based on measurements and model simulations to 24years for the Upper Sheep Creek (USC) catchment, a 26ha, snow-fed, semi-arid rangeland headwater drainage within the Reynolds Creek Experimental Watershed in southwestern Idaho, USA.

What lies beneath: detecting sub‐canopy changes in savanna woodlands using a three‐dimensional classification method

Journal Articles & Books
Diciembre, 2015

QUESTION: Increasing population pressure, socio‐economic development and associated natural resource use in savannas are resulting in large‐scale land cover changes, which can be mapped using remote sensing. Is a three‐dimensional (3D) woody vegetation structural classification applied to LiDAR (Light Detection and Ranging) data better than a 2D analysis to investigate change in fine‐scale woody vegetation structure over 2 yrs in a protected area (PA) and a communal rangeland (CR)? LOCATION: Bushbuckridge Municipality and Sabi Sand Wildtuin, NE South Africa.

Vertical dust concentration measurements within the boundary layer to assess regional source–sink relations of dust in semi-arid grasslands of Inner Mongolia, China

Journal Articles & Books
Diciembre, 2015
China

Whether grazed semi-arid grassland can be regarded as a net-sink or net-source of aeolian dust is difficult to detect since deposition and emission processes are in gradual transition. In grassland, dust arrives from sources far away or is directly emitted and immediately part of the suspension load. The processes of dust emission or deposition can be mainly identified by vertical concentration measurements close to the ground and close to the sources.

Modelling the impacts of land-cover change on streamflow dynamics of a tropical rainforest headwater catchment

Journal Articles & Books
Diciembre, 2012
Costa Rica

A modelling experiment is used to examine different land-use scenarios ranging from extreme deforestation (31% forest cover) to pristine (95% forest cover) conditions and related Payment for Ecosystem Services (PES) schemes to assess whether a change in streamflow dynamics, discharge extremes and mean annual water balance of a 73.4-km² tropical headwater catchment in Costa Rica could be detected.

Mercury proxies and mercury dynamics in a forested watershed of the US Northeast

Journal Articles & Books
Diciembre, 2014

Although many studies focus on mercury (Hg) and methylmercury (MeHg) dynamics in streams, challenges remain in identifying the relative importance of land cover and seasonality at regulating Hg and MeHg dynamics at the watershed scale. Developing robust proxies for Hg and/or MeHg determination also remains a challenge. Our study used Hg, MeHg, and dissolved organic carbon (DOC) concentration measurements and various DOC fluorescence indices to characterize Hg and DOC dynamics in a forested watershed of the US Northeast.

Land Use: the Kyoto protocol, the FAO definition of forest and the Italian Inventory of Forests and Carbon Stocks

Journal Articles & Books
Diciembre, 2005
Italia

In 2000, after the international agreement on the Kyoto Protocol of the United Nations Framework Convention on Climate Change, the United Nation Food and Agriculture Organization decided to adopt a new set of basic forest and forest change definitions. The main change is that new definitions are no more related to land cover but to land use. The entry into force of the Kyoto Protocol requires now that national forest related data must be based on land use concept.

Evaluating common drivers for color, iron and organic carbon in Swedish watercourses

Journal Articles & Books
Diciembre, 2014

The recent browning (increase in color) of surface waters across much of the northern hemisphere has important implications for light climate, ecosystem functioning, and drinking water treatability. Using log-linear regressions and long-term (6–21 years) data from 112 Swedish watercourses, we identified temporal and spatial patterns in browning-related parameters [iron, absorbance, and total organic carbon (TOC)]. Flow variability and lakes in the catchment were major influences on all parameters.

Fish Influences on Amphibian Presence and Abundance in Prairie and Parkland Landscapes of Minnesota, USA

Journal Articles & Books
Diciembre, 2013
Estados Unidos de América

Many amphibian populations are declining, and increased understanding of the drivers of amphibian presence and abundance will help in their conservation. In 2005 and 2006 we estimated relative abundance of larvae of two common amphibian taxa, Tiger Salamanders (Ambystoma tigrinum) and ranid tadpoles (Northern Leopard Frog Lithobates pipiens and Wood Frog Lithobates sylvaticus), in 75 shallow lakes in prairie and parkland areas in Minnesota.

Environmental risk factors for equine West Nile virus disease cases in Texas

Journal Articles & Books
Diciembre, 2009

West Nile Virus (WNV) was first detected in the Texas equine population during June 2002. Infection has since spread rapidly across the state and become endemic in the equine population. Environmental risk factors associated with equine WNV attack rates in Texas counties during the period 2002 to 2004 were investigated. Equine WNV attack rates were smoothed using an empirical Bayesian model, because of the variability among county equine populations (range 46-9,517).

Land Cover Mapping for Namdapha National Park (Arunachal Pradesh), India Using Harmonized Land Cover Legends

Journal Articles & Books
Diciembre, 2014
India

Since last few decades RS-GIS is playing vital role in studying and mapping spatiotemporal responses of land cover, however, as a matter of fact, the mapping outputs largely depend on the expert's/user's preferences because location specific and people specific land cover classification systems are adopted autonomously for image classification in GIS. This may actually lead to an ambiguous definition of a particular land cover type when such different maps are compared at global level.

Potential habitat corridors and restoration areas for the black-and-white snub-nosed monkey Rhinopithecus bieti in Yunnan, China

Journal Articles & Books
Diciembre, 2015
China

The black-and-white snub-nosed monkey Rhinopithecus bieti is endemic to China, where its population is fragmented into 15 isolated groups and threatened despite efforts to protect the species. Here we analyse possible habitat connectivity between the groups reported in Yunnan, using genetic, least-cost path and Euclidean distances. We detect genetic isolation between the northern and southern groups but not among the northern groups. We show that genetic distance is better explained by human disturbance and land-cover least-cost paths than by Euclidian distance.

Do farming practices affect natural enemies at the landscape scale?

Journal Articles & Books
Diciembre, 2015
Francia

Farming practices are rarely considered in the description of agricultural landscapes. However, the variety of cropping systems creates a particular kind of heterogeneity which can strongly affect the diversity of species living in agro-ecosystems, and consequently the ecosystem services they provide. In this study, we investigate the effects of landscape composition and configuration of organic and conventional farming practices on three groups of aphids’ natural enemies, compared to field habitat quality and land cover heterogeneity.