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Life History and Demography of Astragalus microcymbus Barneby (Fabaceae)

Journal Articles & Books
Dezembro, 2013

Astragalus microcymbus (Fabaceae) is a rare forb endemic to Gunnison County, Colorado. For 17 years, Denver Botanic Gardens and the U.S. Bureau of Land Management (Colorado State Office) have monitored four populations of this candidate species under the ESA in the South Beaver Creek Natural Area. Large, statistically significant population declines have been documented, as have prolonged dormancy, episodic fruit production, and herbivory.

Modeling Spatially Explicit Densities of Endangered Avian Species in a Heterogeneous Landscape

Journal Articles & Books
Dezembro, 2013

Relating population density to spatially explicit habitat characteristics can inform management by directing efforts to areas with lower densities or focusing conservation and land protection on high-density areas. We conducted point-transect surveys for the endangered Golden-cheeked Warbler (Setophaga chrysoparia) and Black-capped Vireo (Vireo atricapilla) in the live-fire region of Fort Hood, Texas. We used mark—recapture distance sampling and combined a Horvitz-Thompson estimator with a habitat-based, resourceselection gradient to estimate spatially explicit density for both species.

Impacts of tracked vehicles on sediment from a desert soil

Journal Articles & Books
Dezembro, 2003

Off-road military vehicle traffic is a major consideration in the management of military lands. The objective of this study was to determine the impacts of military tracked M1A1 heavy combat tank vehicles on sediment loss from runoff, surface plant cover, and surface microtopography in a desert military training environment. A randomized block design was used which had 10 blocks with 4 plots (0.5 m2) in each block.

Quandaries of a decade‐long restoration experiment trying to reduce invasive species: beat them, join them, give up, or start over?

Journal Articles & Books
Dezembro, 2016

We evaluate the outcomes and consequences of a decade‐long restoration project in a Hawaiian lowland wet forest as they relate to long‐term management actions. Our initial study was designed both to promote native biodiversity and to develop knowledge that would enable land management agencies to restore invaded forests. Our premise of success followed the prevalent perception that short‐term management, such as removal of invasive species, ideally translates into long‐term and sustainable restoration.

On the improvement of land management schemes and programs of social and economic development of the administrative districts in the Republic of Belarus

Conference Papers & Reports
Dezembro, 2011
Letónia
Bielorrússia

The article provides with a description of sectorial and regional planning in the Republic of Belarus which consists of a hierarchically organized system of socio-economic development programs of the republic, its regions and districts as well as the complex of documents of regional planning. Being under development the land tenure schemes for administrative districts should be most closely linked to the Programs of socio-economic development of the districts. For the next five-year plan it’s proposed the standard structure of the document.

Deposition of sand over a cyanobacterial soil crust increases nitrogen bioavailability in a semi-arid woodland

Journal Articles & Books
Dezembro, 2011

The movement of sand by erosion is a common feature of drylands during droughts and periods of sparse vascular plant cover. We examined the effects of sand deposition on the bioavailability of N in cyanobacterial-dominant soil crusts during and after a severe drought. Crusts were sampled from two depths on stony and stone-free surfaces with and without sandy deposits. All sites supported an extensive cover (up to 51%) of N-fixing cyanobacteria and cyanolichens.

Using Benefit Transfer to Estimate Average Relative Marginal Values for Wildland Fire Program Planning

Journal Articles & Books
Dezembro, 2014
Estados Unidos

We developed a set of generalized value categories and average relative marginal values using resource and valuation information collected at seven federal land management planning units in the USA. The categories and average values are intended to be used for rapid strategic wildland fire program planning or as foundation values for a more extended planning effort. To divide the original information into logical and statistically valid value categories, we used a k-means cluster analysis combined with expert knowledge of how each resource type is managed with respect to fire.

Spatial dependence of predictions from image segmentation: A variogram-based method to determine appropriate scales for producing land-management information

Journal Articles & Books
Dezembro, 2010

A significant challenge in ecological studies has been defining scales of observation that correspond to the relevant ecological scales for organisms or processes of interest. Remote sensing has become commonplace in ecological studies and management, but the default resolution of imagery often used in studies is an arbitrary scale of observation. Segmentation of images into objects has been proposed as an alternative method for scaling remotely-sensed data into units having ecological meaning.

comparison of alternative modelling approaches to evaluate the European forest carbon fluxes

Journal Articles & Books
Dezembro, 2010
Europa

The European forest carbon balance studied by various methods shows different results. We compared the regional and national net primary production (NPP) estimated by the forest inventory-based model EFISCEN and the climate-based terrestrial ecosystem models (TEMs: BIOME-BGC, ORCHIDEE, and JULES), and single forests NPP derived from the international network of eddy-covariance towers (FLUXNET). In addition, the paper presents the net ecosystem production (NEP) and the net biome production (NBP) calculated with EFISCEN and discusses the influence of forest management onto carbon fluxes.

Simple Approaches to Improve Restoration of Coastal Sage Scrub Habitat in Southern California

Journal Articles & Books
Dezembro, 2016

Much of the coastal sage scrub habitat in Southern California that existed prior to European settlement has been developed for human uses. Over the past two to three decades, public agencies and land conservation organizations have worked to acquire some of the remaining lands for preservation. Many of these lands are degraded by past intensive livestock grazing, farming, and frequent fires, and the native flora has been replaced by weedy, exotic annual grasses and forbs, mostly of Mediterranean origin.