نتایج جستجو برای: shrub canopy

تعداد نتایج: 19636  

2008
C. Armas O. E. Sala

The plant community in the Patagonian steppe is arranged in two structural patch types: scattered grasses and shrubs, which are often surrounded by a ring of grasses. Previous studies suggested that this pattern results from a cyclical succession driven by plant interactions. Although there is a good understanding of the factors affecting the formation of the grass rings encircling the shrubs, ...

2013
C. Joshi J. van Andel A. Skidmore J. de Leeuw I. V. Duren

In this paper, the researchers investigate the vegetative growth of Chromolaena odorata and the infl uence of light intensity on the understorey environment of Shorea robusta forest at Chitwan in south-central Terai, Nepal. C. odorata is a clonally growing shrub and typically consists of several clones with an underground “cormous organ” (a modifi ed stem to store food reserve; here after “corm...

2007
Chad S. Boyd Jon D. Bates Rick F. Miller

Sagebrush cover is often estimated with the use of the line intercept method. However, a lack of standardized protocols may lead to variable estimates of sagebrush canopy cover. Our objectives were to determine the influence of gap size on 1) sagebrush canopy cover estimates, 2) time needed to read a transect, and 3) among-observer variability in sagebrush canopy cover estimates. We utilized 5-...

2004
R O Powlesland

The foraging behaviour, diet and habitat use of North Island kokako (Callaeas cinerea wilsoni) were studied in Puketi State Forest from October 1981 to August 1982. Kokako fed mainly from branches and twigs of canopy and upper-understorey plants. Although 68 different foods were eaten, only eight contributed more than 5% to the observed diet in any season. The diet consisted of fruit (44%), unk...

2015
James L. Hanula Scott Horn Joseph J. O’Brien

Two conservation goals of the early 20th century, extensive reforestation and reduced wildfire through fire exclusion, may have contributed to declining pollinator abundance as forests became denser and shrub covered. To examine how forest structure affects bees we selected 5 stands in each of 7 forest types including: cleared forest; dense young pines; thinned young pines; mature open pine wit...

2009
M. Lorraine Tighe Heather McNairn

Vegetation canopy height is one of the fundamental structural parameters for estimating forest biomass and evaluating forest carbon balance. Remote sensing technologies like interferometric synthetic aperture radar (abbreviated as IFSAR or IFSAR) may provide a means to extract vegetation canopy heights remotely. A comparison of canopy height estimates derived from IFSAR scattering phase center ...

2007
Gene Albanese Peter D. Vickery Paul R. Sievert

Changes to land use and disturbance frequency threaten disturbance-dependent Lepidoptera within sandplain habitats of the northeastern United States. The frosted elfin (Callophrys irus) is a rare and declining monophagous butterfly that is found in xeric open habitats maintained by disturbance. We surveyed potential habitat for adult frosted elfins at four sites containing frosted elfin populat...

Mansour Mesdaghi, Mohammad Jankju Tahereh Sadeghi Shahrakht

In arid and semi-arid ecosystems, shrubs may act as fertility islands but theireffect may vary depending on their morphology and ecological impacts. This research wasaimed to study effect of three shrubs Scariola orientalis, Astragalus heratensis, and Rosapersica on soil properties and on the microclimate conditions (temperature, luminance, andsoil moisture) of their understory in the steppe ra...

Journal: :Global change biology 2013
Beth A Newingham Cheryl H Vanier Therese N Charlet Kiona Ogle Stanley D Smith Robert S Nowak

Elevated atmospheric CO2 concentrations ([CO2 ]) generally increase primary production of terrestrial ecosystems. Production responses to elevated [CO2 ] may be particularly large in deserts, but information on their long-term response is unknown. We evaluated the cumulative effects of elevated [CO2 ] on primary production at the Nevada Desert FACE (free-air carbon dioxide enrichment) Facility....

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