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

Journal Articles & Books
Décembre, 2002
Espagne

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
Décembre, 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).

How Certain Are Salmon Recovery Forecasts? A Watershed-scale Sensitivity Analysis

Journal Articles & Books
Décembre, 2010
États-Unis d'Amérique

Complex relationships between landscape and aquatic habitat conditions and salmon (Oncorhynchus spp.) populations make science-based management decisions both difficult and essential. Due to a paucity of empirical data, models characterizing these relationships are often used to forecast future conditions. We evaluated uncertainties in a suite of models that predict possible future habitat conditions and fish responses in the Lewis River Basin, Washington, USA. We evaluated sensitivities of predictions to uncertainty in model parameters.

Grazing-Induced Modifications to Peak Standing Crop in Northern Mixed-grass Prairie

Journal Articles & Books
Décembre, 2007

Selective grazing can modify the productive capacity of rangelands by reducing competitiveness of productive, palatable species and increasing the composition of more grazing-resistant species. A grazing system (season-long and short-duration rotational grazing) x stocking rate (light: 16 steers·80 ha-1, moderate: 4 steers·12 ha-1, and heavy: 4 steers·9 ha-1) study was initiated in 1982 on northern mixed-grass prairie. Here, we report on the final 16 years of this study (1991-2006). Spring (April+May+June) precipitation explained at least 54% of the variation in peak standing crop.

Habitat Effects on Condition of Doe Mule Deer in Arid Mixed Woodland-grassland

Journal Articles & Books
Décembre, 2007

Productivity of mule deer (Odocoileus hemionus Raf.) populations is closely linked to individual nutritional condition. We modeled body fat of individual does as a function of vegetation cover, composition, and water characteristics of their annual, summer, and winter home ranges in north-central New Mexico. We also modeled home range size as a function of the same characteristics. Levels of body fat were most closely and negatively related to the amount of pinyon-juniper in an individual deer's annual home range (F1,21=7.6; P=0.012; r2=0.26).

Global versus local change effects on a large European river

Journal Articles & Books
Décembre, 2012
France
Global

Water temperature and discharge are fundamental to lotic ecosystem function, and both are strongly affected by climate. In large river catchments, however, climatic effects might be difficult to discern from background variability and other cumulative sources of anthropogenic change arising from local land and water management.

Bundled Adoption of Precision Agriculture Technologies by Cotton Producers

Journal Articles & Books
Décembre, 2015

This research analyzes the adoption patterns among cotton farmers for remote sensing, yield monitors, soil testing, soil electrical conductivity, and other precision agriculture technologies using a Multiple Indicator Multiple Causation regression model. Adoption patterns are analyzed using principle component analysis to determine natural technology groupings. Identified bundles are regressed on farm structure and operator characteristics.

Simulation of the Consequences of Different Fire Regimes to Support Wildland Fire Use Decisions

Journal Articles & Books
Décembre, 2007

The strategy known as wildland fire use, in which lightning-ignited fires are allowed to burn, is rapidly gaining momentum in the fire management community. Managers need to know the consequences of an increase in area burned that might result from an increase in wildland fire use. One concern of land managers as they consider implementing wildland fire use is whether they can meet the goals in the land management plan for the desired distribution of forest structural stages across the landscape with further increases in fire.

spatio-temporal invariability of sediment concentration and the flow–sediment relationship for hilly areas of the Chinese Loess Plateau

Journal Articles & Books
Décembre, 2013

The spatio-temporal variation underlies and complicates studies related to earth surface processes. Subsequent to our previous studies reporting the temporal invariability of sediment concentration, this study further reports the spatial invariability of sediment concentration or the flow–sediment relationship in the hilly part of the Chinese Loess Plateau. The dense channel network dissects this area into numerous sub-watersheds, which are composed of entire slopes (a combination of the hill slope and the valley side slope).

“With the Stroke of a Pen”: Designation of the Grand Staircase Escalante National Monument and the Impact on Trust

Journal Articles & Books
Décembre, 2013

In September of 1996, without prior warning to Utah residents, the Clinton Administration announced the creation of the Grand Staircase-Escalante National Monument (GSENM) in southern Utah. Reactions by residents in neighboring gateway communities were both swift and intense. Lack of citizen input in the process drew ire among Utah citizens living near the monument and statewide. In this article we examine how the designation process has impacted residents’ trust in the federal agency managing the monument—the Bureau of Land Management.

Dynamics of fractionated P and P budget in soil under different land management in two Tanzanian croplands with contrasting soil textures

Journal Articles & Books
Décembre, 2012
Tanzania

Phosphorus deficiency is one of the largest constraints to crop production in tropical African soils owing to low native soil P and the high P fixation capacity of highly weathered soils. To achieve better soil P management, it is necessary to evaluate the effects of land management on soil P dynamics and P budget. We conducted a 4-year cultivation experiment in two dry tropical croplands in Tanzania at two sites with contrasting soil textures, viz. clayey and sandy.

Making sense of policy implementation: The construction and uses of expertise and evidence in managing freshwater environments

Journal Articles & Books
Décembre, 2013

This paper explores how environmental policy is implemented and enacted through the management of technical and institutional knowledge at the local level. We use the conservation of the freshwater pearl mussel in the River Esk, North Yorkshire, UK, as an empirical case study to examine the interaction that takes place between professionals from different institutional and disciplinary backgrounds as they come together to work on a common problem. We focus on two aspects: the way in which an institutional context was created; and the interaction between the professionals involved.