in order to sustainable use of rangelands, it is necessary to recognize water, soil, and vegetation cover and analyze their relationships. physical and chemical properties of soil are effective in distribution of plant species in local area. to determine the effects of some soil properties on species distribution of eurotia ceratoides and stipa barbata in baghedar summer region of bafgh, three ...

Afforestation, settled before 60–90 years and adjacent solonetzic grasslands, representing the natural vegetation cover were compared in this study based on their basic soil characteristics (pH, CaCO3 content, organic carbon (SOC), exchangeable sodium percentage (ESP)) up to 2 m depth. The assumption was that plantings of arbour can change sodic soils not only superficial layers but even larger...

drying is considered as one of the important stages after plant harvesting which plays an important role in maintaining the quantity and quality of their active ingredients. st. john's wort (hypericum perforatum l.) is an important medicinal plant that high percentages of hypericin in its leaves and flowers are considered as the most important feature of the iranian species. in this resear...

root morphological and distribution responses of signal grass (brachiaria decumbens) to long-term cattle grazing were examined in a tropical pasture in malaysia. the treatments were no grazing by cattle and grazing at a moderate stocking density (2.7 animal unit/ha) under rotational grazing for 33 years. the method consists of taking soil core using a soil corer to a depth of 30 cm and extracti...

This study was conducted to determine soil properties that correlate with the arbuscular mycorrhizal fungal (AMF) spore numbers in semiarid calcareous soils of Hamadan province in northwestern of Iran. Soil samples from six sites managed differently were collected from a 0 to 30 cm depth. The results showed that land use and management systems had a significant effect on AMF spore number in soi...

Forest soils represent a substantial portion of the terrestrial carbon (C) pool, and changes to soil C cycling are globally significant not only for C sequestration but also for sustaining forest productivity and ecosystem services. To quantify the effect of harvesting on soil C, we used meta-analysis to examine a database of 945 responses to harvesting collected from 112 publications from arou...

With the degradation of global lake ecosystem, aquatic plants are more and widely used in ecological restoration. The effects water depths on growth photosynthetic fluorescence characteristics two emergent (Typha orientalis Zizania caduciflora) were studied eutrophic Lake Gehu by in-situ experiments. results showed that depth had no significant effect germination plants. changed morphological P...

Effects of water depth, burn duration, and diesel fuel concentration on the relationship between recovery of marsh vegetation, soil temperature, and oil remediation during in-situ burning of oiled mesocosms were investigated. The water depth over the soil surface during in-situ burning was a major factor controlling recovery of the salt marsh grass, Spartina alterniflora. Ten centimeters of wat...

Stagnant flooding (SF) is a major problem in rainfed lowlands where floodwater of 25-50 cm stagnates in the field for most of the season. We aimed to establish a system for phenotyping SF tolerance and identifying tolerant germplasm through screening of landraces. A total of 626 rice accessions were evaluated over 3 years under control conditions and two levels of SF. Floodwater was raised to 2...

the aim of this study is to provide a control software system, based on monte carlo simulation, and calculations of dosimetric parameters of standard and wedge radiation fi elds, using a monte carlo method. gate version 6.1 (opengate collaboration), was used to simulate a compact 6 mv linear accelerator system. in order to accelerate the calculations, the phase-space technique and cluster compu...