plant cover is one of the most important factors affecting infiltration rate of water into the soil and decreasing runoff. distribution of plants in arid and semi-arid areas is almost patchy and form different patterns. one of the fascinating patterns is ring-shaped growth pattern. ring patterns of varying size are formed by clonally reproducing grasses, sedges and even shrubs growing in resour...

Tree recruitment is a key process underlying stand dynamics and sustainability in managed forests. Woody plant cover is known to affect the regeneration success of Pinus nigra, suggesting the existence of facilitative plant-plant interactions. The regeneration patterns of this Mediterranean pine were analyzed across its distribution area, using data from 3226 plots of the Spanish National Fores...

The effects of soil disturbance on the nematode community were assessed at 30 sites on the outer coastal plain of Mississippi, representing four ages since soil disturbance plus a control group of six undisturbed sites. Thirty-five taxa were encountered, dominated in abundance and taxonomic richness by plant and bacterial feeders. Nematodes were more abundant and more taxonomically rich in site...

Regional analyses of biogeochemical processes can benefit significantly from observational information on land cover, vegetation structure (e.g., leaf area index), and biophysical properties such as fractional PAR absorption. Few remote sensing efforts have provided a suite of plant attributes needed to link vegetation structure to ecosystem function at high spatial resolution. In arid and semi...

Most snow mold pathogens cause plant injury only under prolonged snow cover, so snow mold diseases are severe primarily in regions where snow cover persists for more than 100 days. Even within these regions, disease occurrence and severity varies greatly from year to year. When disease is severe, individual fungal colonies coalesce, resulting in substantial losses in plant stand (20). In other ...

The distribution of flowering across the growing season is governed by each species' evolutionary history and climatic variability. However, global change factors, such as eutrophication and invasion, can alter plant community composition and thus change the distribution of flowering across the growing season. We examined three ecoregions (tall-, mixed, and short-grass prairie) across the U.S. ...

The abundance of plants with extrafloral nectaries was determined for a series of temperate habitats in Nebraska. Mean cover of plants with extrafloral nectaries was 1.3% in riparian forest understory, 1.8% in virgin deciduous forest understory, 0.0% in tall-grass prairie, and 8.3% in sandhill prairie. Sandhills prairie contained distinct communities with different mean cover of plants with ext...

Studies quantifying habitat structure generally use several instruments. This paper aims to propose a new and efficient device to characterize microhabitat structure of small mammals. Seven measurements were taken: plant cover, litter cover, rock cover, canopy cover, and vegetative obstruction at three heights. The device is a 0.25 m2 square wooden frame (0.50 m x 0.50 m) divided in to 100 open...

Loss of grassland species resulting from activities such as off-road vehicle use increases the need for models that predict effects of anthropogenic disturbance. The relationship of disturbance by military training to plant species richness and composition on two soils (Foard and Lawton) in a mixed prairie area was investigated. Track cover (cover of vehicle disturbance to the soil) and soil or...

Positive plant interactions have strong effects on plant diversity at several spatial scales, expanding species distribution under stressful conditions. We evaluated the joint effect of climate and grazing on the nurse effect of Croton wagneri, by monitoring several community attributes at two spatial scales: microhabitat and plant community. Two very close locations that only differed in grazi...