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Climate impacts on net primary productivity trends in natural and managed ecosystems of the central and eastern United States

Journal Articles & Books
Dezembro, 2009
Estados Unidos

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.

Assessing net carbon sequestration on urban and community forests of northern New England, USA

Journal Articles & Books
Dezembro, 2013
Estados Unidos

Urban and community forests play an important role in the overall carbon budget of the USA. Accurately quantifying carbon sequestration by these forests can provide insight for strategic planning to mitigate greenhouse gas effects on climate change. This study provides a new methodology to estimate net forest carbon sequestration (FCS) in urban and community lands of northern New England using ground based forest growth rates, housing density data, satellite derived land cover and tree canopy cover maps at the county level.

Possible impacts of climate change on water quality in streams of the Czech Republic

Journal Articles & Books
Dezembro, 2015
República Checa

The impacts of changes in water temperature and flow on selected water quality parameters, as one of the consequences of climate change, were studied in river catchments in the Czech Republic with little anthropogenic influence. The impact of climate change was manifested by an increase in stream temperature by 1.15°C over 28 years. The selected water quality parameters were dependent on flow, with up to 10-fold increases in the concentrations of ammonia, phosphorus and chlorophyll- a at minimum flow levels.

Natural Regeneration Processes in Big Sagebrush (Artemisia tridentata)

Journal Articles & Books
Dezembro, 2014

Big sagebrush, Artemisia tridentata Nuttall (Asteraceae), is the dominant plant species of large portions of semiarid western North America. However, much of historical big sagebrush vegetation has been removed or modified. Thus, regeneration is recognized as an important component for land management. Limited knowledge about key regeneration processes, however, represents an obstacle to identifying successful management practices and to gaining greater insight into the consequences of increasing disturbance frequency and global change.

Relation between Occupancy and Abundance for a Territorial Species, the California Spotted Owl

Journal Articles & Books
Dezembro, 2013

Land and resource managers often use detection–nondetection surveys to monitor the populations of species that may be affected by factors such as habitat alteration, climate change, and biological invasions. Relative to mark‐recapture studies, using detection–nondetection surveys is more cost‐effective, and recent advances in statistical analyses allow the incorporation of detection probability, covariates, and multiple seasons.

Eliciting expert knowledge to inform landscape modeling of conservation scenarios

Journal Articles & Books
Dezembro, 2012

Conservation and land management organizations such as The Nature Conservancy are developing strategies to distribute conservation efforts over larger areas. Relative to fee-simple protection efforts, strategies that allow ecologically sustainable timber harvest and recreation activities, such as working forest conservation easements, should yield greater socioeconomic benefits (ecosystem services) with less investment per area without significantly compromising the conservation of biodiversity (ecological targets).

causes, effects and challenges of Sahelian droughts: a critical review

Journal Articles & Books
Dezembro, 2014

This paper is a critical synthesis of the causes, effects and challenges of the Sahelian droughts. The results show that the four main causes of the Sahelian droughts are as follows: sea surface temperature changes, vegetation and land degradation, dust feedbacks and human-induced climate change. However, human-induced climate change is seen as the major drought-determining factor because it controls sea surface temperatures, dust feedbacks and vegetation degradation.

Epistemic uncertainty in predicting shorebird biogeography affected by sea-level rise

Journal Articles & Books
Dezembro, 2012

Accurate spatio-temporal predictions of land-cover are fundamentally important for assessing geomorphological and ecological patterns and processes. This study quantifies the epistemic uncertainty in the species distribution modeling, which is generated by spatio-temporal gaps between the biogeographical data, model selection and model complexity. Epistemic uncertainty is generally given by the sum of subjective and objective uncertainty. The subjective uncertainty generated by the modeler-choice in the manipulation of the environmental variables was analyzed.

relationship between precipitation anomalies and satellite-derived vegetation activity in Central Asia

Journal Articles & Books
Dezembro, 2013
Ásia Central

In Central Asia, water is a particularly scarce and valuable good. In many ecosystems of this region, the vegetation development during the growing season is dependent on water provided by rainfall. With climate change, alterations of the seasonal distribution of precipitation patterns and a higher frequency of extreme events are expected. Vegetation dynamics are likely to respond to these changes and thus ecosystem services will be affected.

Post-wildfire soil erosion in the Mediterranean: Review and future research directions

Journal Articles & Books
Dezembro, 2011
Israel
Espanha

Wildfires increased dramatically in frequency and extent in the European Mediterranean region from the 1960s, aided by a general warming and drying trend, but driven primarily by socio-economic changes, including rural depopulation, land abandonment and afforestation with flammable species. Published research into post-wildfire hydrology and soil erosion, beginning during the 1980s in Spain, has been followed by studies in other European Mediterranean countries together with Israel and has now attained a sufficiently large critical mass to warrant a major review.

Climate change and impact of desertification or soil/ land degradation in Turkey, combating desertification

Journal Articles & Books
Dezembro, 2008
Turquia

The total arable land of Turkey is about 28,054,000 ha. The main income of the country is agriculture and agriculture based industry. However, the prime soils cover only 17.5% of the total land surface and the productivity of the rest of the soils is limited by topographical, chemical (e.g. high calcium carbonate content, alkalinity and low organic matter), and physical (e.g. water logging, texture) attributes. The diverse topography along with deforestation and unsuitable tillage and irrigation management has been inducing the rate of erosion in the country for centuries.

Soil degradation and food security coupled with global climate change in northeastern China

Journal Articles & Books
Dezembro, 2013
China

The northeastern China is an important commodity grain region in China, as well as a notable corn belt and major soybean producing area. It thus plays a significant role in the national food security system. However, large-scale land reclamation and non-optimum farming practices give rise to soil degradation in the region. This study analyzed the food security issues coupled with global climate change in the northeastern China during 1980–2000, which is the period of modern agriculture.