flood spreading has an effective role in the soil improvement and fertility, ground water storage, revival of vegetation and prevention of fluent sands movement. one of the main problem of flood spreading projects is the entrance of sediment to the spreading systems and sedimentation in it. sediment reduces the efficiency of the flood spreading system and after awhile lose its efficiency.the ma...

In the cold temperate zone of western and southern slopes Changbai Mountain, Betula ermanii Cham. forest, Picea jezoensis (Siebold & Zucc.) Carrière mixed forests B. P. are heterogeneously distributed in a mosaic patches, reason for this formation is still unclear. August 1986, typhoon disturbed on forming large number forest gaps. After more than 30 years vegetation succession, patches wind-st...

Many researchers hypothesize that plant richness declines at high soil fertility (and high productivity) due to light limitation. We tested this hypothesis in an old-field by independently manipulating fertilization and light levels via shade cloth (decreased light), vegetation tie-backs (increased light) and vegetation clipping (increased light). Droughts occurred during two of the four years ...

Cover crops are essential in agricultural management and especially in organic farming for protecting the soil from erosion, competing with weeds, preventing evaporative losses and improving soil quality and fertility. The choice of cover crop species is crucial in achieving the highest level of weed suppression and soil fertility enhancement. Cover crop systems with rye or mixtures of legumes ...

Determining how anthropogenic disturbances affect site productivity through bioassays requires a complete understanding of both overstory and understory vegetation. This study was installed in 1997 to determine how soil compaction and intensive harvesting affected the inherent site productivity of pine stands on the western boundary of loblolly pine’s (Pinus taeda L.) natural range. We measured...

Soil microbial communities are very sensitive to changes in land use and are often used as indicators of soil fertility. We evaluated the microbial communities in the soils of four types of vegetation (cropland (CP), natural grassland (NG), broadleaf forest (BF) and coniferous forest (CF)) at depths of 0–10 and 10–20 cm on the Loess Plateau in China using phospholipid fatty acid (PLFA) profilin...

The vegetation of an area of the Upper Clutha basin, New Zealand, with a 'semi-arid' climate, was sampled with 95 quadrats in a nested randomised design. All types of vegetation were sampled, from nearnatural to managed pastures. Twenty four environmental factors were measured in each quadrat. Five 'formations' are described, and 14 'communities' recognised within them, although there are few c...

The ecosite unit in Ontario‘s boreal forest ecological land classification system is a polygon of common vegetation type and soil conditions intended to provide a standardized provincial framework to inform meso-scale forestry and planning applications. To determine whether the physical factors used for ecosite classification relate to patterns in ecological function over finer spatial scales, ...