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Saving the sagebrush sea: an ecosystem conservation plan for big sagebrush plant communities

Journal Articles & Books
Diciembre, 2011

Vegetation change and anthropogenic development are altering ecosystems and decreasing biodiversity. Successful management of ecosystems threatened by multiple stressors requires development of ecosystem conservation plans rather than single species plans. We selected the big sagebrush (Artemisia tridentata Nutt.) ecosystem to demonstrate this approach. The area occupied by the sagebrush ecosystem is declining and becoming increasingly fragmented at an alarming rate because of conifer encroachment, exotic annual grass invasion, and anthropogenic development.

Land use regulates carbon budgets in eastern Germany: From NEE to NBP

Journal Articles & Books
Diciembre, 2010
Alemania

The concentration of carbon dioxide in the atmosphere is influenced by land use and management. Here, the carbon (CO₂-C) budgets of a managed forest (spruce), a grass site and a crop site (crop rotation) have been compared to examine the effects of different management practices on net ecosystem exchange (NEE) and net biome productivity (NBP). This approach enables a more comprehensive carbon budgeting as it takes into account carbon exports and imports for particular land uses.

Factors determining soil nutrient distribution in a small-scaled watershed in the purple soil region of Sichuan Province, China

Journal Articles & Books
Diciembre, 2009
China

Determining soil nutrient distribution is critical to identify sites which are at risk of N and P loading. Equally important are determining factors that influence such distribution (e.g. land use, land management, topography, etc.). In this research, soil nutrient distribution and its influencing factors were studied in a small-scaled watershed in the purple soil region of Sichuan Province, China. The watershed is 1.3km² with a complex land management system including agriculture and forestry.

Linkages between land management activities and water quality in an intensively farmed catchment in southern New Zealand

Journal Articles & Books
Diciembre, 2007
Nueva Zelandia

Linkages between land management activities and stream water quality are reported for a 2480 ha catchment used for dairy farming, sheep-beef farming and forestry in Southland, New Zealand. Our approach was to reconcile measured loads of nutrients exported from the catchment with those estimated based on characterisation of farming practices within the catchment. The latter was based upon detailed surveys of farm practices and soil quality.

Image interpreter tool: An ArcGIS tool for estimating vegetation cover from high-resolution imagery

Journal Articles & Books
Diciembre, 2011

Land managers need increased temporal and spatial resolution of rangeland assessment and monitoring data. However, with flat or declining land management and monitoring agency budgets, such increases in sampling intensity are unlikely unless new methods can be developed that capture data of key rangeland indicators at a lower cost. Remote sensing techniques have shown promise for collecting plant community composition and ground cover data efficiently. However, many image analysis techniques require software and expertise not always available to field offices.

Effects of management regimes and extreme climatic events on plant population viability in Eryngium alpinum

Journal Articles & Books
Diciembre, 2012

Extreme climatic events like the 2003 summer heatwave and inappropriate land management can threaten the existence of rare plants. We studied the response of Eryngium alpinum, a vulnerable species, to this extreme climatic event and different agricultural practices. A demographic study was conducted in seven field sites between 2001 and 2010. Stage-specific vital rates were used to parameterize matrix population models and perform stochastic projections to calculate population growth rates and estimate extinction probabilities.

Coronilla juncea is both a nutritive fodder shrub and useful in the rehabilitation of abandoned Mediterranean marginal farmland

Journal Articles & Books
Diciembre, 2002
España

Coronilla juncea is a leguminous shrub native to semi-arid regions of the Mediterranean Basin, particularly south-eastern Spain, and is browsed by livestock such as sheep and goats. We provide here information about this source of forage: allometric regression equations (phytovolume vs. total and forage phytomass), nutritive value and seed germination. The regression equations calculated were highly significant (r2= 0·86 for volume/total phytomass and 0·93 for volume/forage phytomass, p

stochastic movement simulator improves estimates of landscape connectivity

Journal Articles & Books
Diciembre, 2015

Conservation actions often focus on restoration or creation of natural areas designed to facilitate the movements of organisms among populations. To be efficient, these actions need to be based on reliable estimates or predictions of landscape connectivity. While circuit theory and least‐cost paths (LCPs) are increasingly being used to estimate connectivity, these methods also have proven limitations. We compared their performance in predicting genetic connectivity with that of an alternative approach based on a simple, individual‐based “stochastic movement simulator” (SMS).