this research has been done with the aim of explaining environmental and managerial factors that affects on rangeland vegetation distribution in saral rangelands of kurdistan province. after selecting plant types as working area were done sampling from plant types and determined some of plants parameters such as kind and number of plants and cover percentage. various environmental factors such ...

The within-site variability of soil characteristics on sites with different soil types remains poorly quantified, although this information is crucial for the success of research on soil properties, and especially for monitoring soil properties over time. We used coefficients of variation and multilevel variance component models to examine the within-site variation of soil (0–30 cm) mineral nut...

A sole-carbon-source catabolism assay (Biolog GN microplate) was used to study whether bacterial communities from the same vertic soil, but under different management history, showed distinctive patterns of C-substrate utilization. Two sampling depths (0–7.5 and 7.5–15 cm) were also investigated. The response of microbial communities to increasing periods of time — 16, 26 and 40 years (S2, S3, ...

there are many remediating methods for the polluted soils but only phytoremediation is a cost effective, environmental friendly, aesthetically pleasing approach that is most suitable for many countries. the purpose of this study was to investigate the potential of native plants for phytoremediation of contaminated soils with lead, zinc, cadmium and nickel in the rangelands around national lead ...

Pesticide use in agriculture can cause undesirable effects to the natural environment as well as to humans. A field trial to determine residues of 2,4-D and paraquat in the ricefield soil and surface water of the drainage canals in the Kerian district of Perak, Malaysia, was conducted during 2006/2007. Analyses of 2,4-D and paraquat in the soil and water samples were carried out using a high pe...

Relationships between soil factors and vegetation types in playa of Damghan was investigated. Six vegetationtypes including Artemisia.sieberi, Arundo. sp, Artemisia.sieberi-Peganum.harmala, Alhagi.cammelerom,Artemisia.sieberi-petropyron.sp, Tamarix.passerinoides-Halocnemum strobilaceum. One bare land was recognized inthe study area and the research was conducted within mentioned types. Canopy p...

An important aspect for estimating optimal N applications is to predict the soil N supply capacity (ability to supply plant-available N) each year. Since fertilizer applications supplement crop N requirements that the soil system cannot meet, understanding potential plant-available N originating from the soil can aid in setting N fertilization rates. General differences in plantavailable N and ...

in order to investigate the effect of wastewater and compost on transport of heavy metals in a soil column, a factorial experiment based on completely randomized design with three replication was conducted. the variables included three types of water: fresh water (w1), treated wastewater (w2) and a composition of 50% raw wastewater and 50% fresh water (w3). besides, four levels of compost were ...