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Effects of climate and land-surface processes on terrestrial dissolved organic carbon export to major U.S. coastal rivers

Journal Articles & Books
Dezembro, 2013

This study aims to understand the influences of climate change and land surface processes on the variation of in-stream DOC concentrations in coastal rivers crossing different climate zones. Monthly observations spanning multiple years in seven major rivers in four different climate zones within the U.S. were analyzed for correlations between dissolved organic carbon (DOC) concentration and surface air temperature, precipitation, land cover and discharge.

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

Journal Articles & Books
Dezembro, 2011
Estados Unidos

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
Dezembro, 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
Dezembro, 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
Dezembro, 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
Dezembro, 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.

Analyzing the contributing factors of timber demand in Bangladesh

Journal Articles & Books
Dezembro, 2012
Bangladesh

This study investigates timber demand in Bangladesh. In evaluating timber demand, the significant contributing factors like forest land cover, frequency of furniture manufacturing, price of timber substitute, population growth and railway density have been examined. Panel data over a longer period for a developing country like Bangladesh were not easily available. The data sources were very sporadic for the study — there was no common data pool. A panel dataset over a 17-year period was simulated and analyzed for the study.

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

Journal Articles & Books
Dezembro, 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
Dezembro, 2013
Estados Unidos

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
Dezembro, 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
Dezembro, 2014
Índia

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
Dezembro, 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.