subalpine rangeland as a rara avis ecosystem is very important because ofecological features. consistency and resistance of this ecosystem is so frangible and itsnatural equilibrium is instable due to the effects of biotic and abiotic factors. the landslideas one of negative consequences in upland area is seen in masoleh watershed (north ofiran). this study has investigated the roles of biotic ...

the study of the relationships of the plant species with the soil in a salty ecosystem would play a significant role in the ecologic programming and management of these inhabitants. the saline and alkaline rangelands of the golestan province are areas that contain salty soil with high underground crusts. the areas are covered by halophyte plants such as frankenia hirsuta. this species is a pere...

studies on vegetation changes of rangelands under grazed and non-grazedconditions are of great importance in the range management planning programs. to determinethe change process of vegetation, this study was performed in inche shorezar site of golestanprovince for nine years (1997-2005). the vegetation parameters were measured every year inseveral fixed plots inside and adjacent of exclosures...

Effects of gizzard shad Dorosoma cepedianum on benthic communities in a large southern reservoir (Lake Texoma, U.S.A.) were examined during two field enclosure and exclosure experiments in which enclosures were stocked at high and low densities in 1998 and 1999, respectively. In both years, chironomid abundance significantly increased in treatments that excluded large fishes from foraging on se...

Feral pigs (Sus scrofa) have caused considerable damage where they have been introduced around the world. At Pinnacles National Monument, California, USA, managers were concerned that feral pigs were damaging wetland habitats, reducing oak regeneration, competing with native wildlife, and dispersing nonnative plant species through soil disturbance. To address these threats the National Park Ser...

Burrowing small mammals in grasslands have long been regarded as pests because they compete for forage with livestock and reduce the forage availability for livestock by destroying pastures through their intensive digging activity. In order to investigate forage competition between the Mongolian Pika (Ochotona pallasi) and livestock an exclosure experiment consisting of four different treatment...