Dynamic global vegetation models simulate feedbacks of vegetation change on ecosystem processes, but direct, experimental evidence for feedbacks that result from atmospheric CO2 enrichment is rare. We hypothesized that feedbacks from species change would amplify the initial CO2 stimulation of aboveground net primary productivity (ANPP) of tallgrass prairie communities. Communities of perennial ...

Red dish mud-rich sed i ments are com mon in sev eral karst ar eas, in the form of red sur face soils and clastic cave in fill ings. The or i gin and sig nif i cance of red sur face soils have been much de bated over re cent years, while clastic mud-rich sed i ments in cave en vi ron ments have re ceived less at ten tion from geoscientists. The ge netic re la tion ship be tween these two ma te ...

Anaerobic soil conditions resulting from flooding often enhance release of phosphorus (P) to overlying water. Enhanced P release is well documented for flooded acidic soils; however, there is little information for flooded alkaline soils. We examined the effect of flooding and anaerobic conditions on P mobilization using 12 alkaline soils from Manitoba that were either unamended or amended with...

expansive behavior is usually observed in soils, which contain fractions of clay minerals in their composition. water absorption of clay particles and change of natural water content of soil up to plastic limit and down to shrinkage limit will cause significant volume change in expansive soils and will result in severe damages to the structures, buildings and foundations. swelling potential is ...

19 Phosphorus (P) losses from agricultural soils constitute a main driver for eutrophication of the 20 Baltic Sea. There is limited knowledge about sorption and release processes of P in these soils, 21 especially concerning the effects of fertilization. In this study, P speciation of the clay fractions 22 from six different soils in long-term fertility experiments in Sweden was investigated by...

Pedogenesis and clay mineralogy of soils and rock samples were studied in a transect of calcareous, gypsiferous, saline soils and sediments of Bakhtegan lake bank in southern Iran. The main objectives of study were to determine the occurrence of clay minerals and factors controlling their distribution pattern and relative abundance in soils and parent materials. The soil parent material is high...

Zinc (Zn) fertilizer is not currently recommended for rice grown on clay or clay loam soils in Arkansas. In 2003, eight field sites were established to evaluate the response of rice grown on clay soils to Zn fertilization. Shortly before or after seeding, granular Zn fertilizer was applied to the soil surface at rates of 0, 5, 10, and 20 lb Zn/acre. Tissue Zn concentration 10 to 14 days after f...

A study was initiated to investigate the relationship between soil test P and depth of soil sampling with runoff losses of dissolved molybdate reactive phosphorus (DMRP). Rainfall simulations were conducted on two noncalcareous soils, a Windthorst sandy loam (fine, mixed, thermic Udic Paleustalf) and a Blanket clay loam (fine, mixed, thermic Pachic Argiustoll), and two calcareous soils, a Purve...