نتایج جستجو برای: soil density
تعداد نتایج: 583021 فیلتر نتایج به سال:
Afforestation is a prevalent practice carried out for soil recovery and carbon sequestration. Improved understanding of the effects of afforestation on soil organic carbon (SOC) content and dynamics is necessary to identify the particular processes of soil organic matter (SOM) formation and/or decomposition that result from afforestation. To elucidate these mechanisms, we have used a sequential...
Soybean cyst nematode (SCN), Heterodera glycines, remains a major yield-limiting pathogen of soybean. Natural suppression of SCN exists and becomes increasingly attractive; however, ecological mechanisms leading to the suppressive state are rarely studied. A glasshouse experiment was performed to determine the effects of soil disturbance and biocides on nematode community and extracellular enzy...
Lettuce was seeded in pots in the greenhouse and in field microplots in 1991 and 1992. Pots and microplots were filled with untreated or fumigated organic soil infested with Meloidogyne hapla at seven initial population densities (Pi) (0 to 32 eggs/cm(3) soil). Lettuce weight, severity of root galling, and number of eggs per root system (Pf) were determined after 8 weeks. At the highest Pi, M. ...
We report above-ground biomass (AGB), basal area, stem density and wood mass density estimates from 260 sample plots (mean size: 1.2 ha) in intact closed-canopy tropical forests across 12 African countries. Mean AGB is 395.7 Mg dry mass ha⁻¹ (95% CI: 14.3), substantially higher than Amazonian values, with the Congo Basin and contiguous forest region attaining AGB values (429 Mg ha⁻¹) similar to...
Restoration of wet prairie in the central midwestern United States should include Prairie cordgrass (Spartina pectinata), but historic densities of this once dominant species are not easily achieved. Spartina pectinata was transplanted into a former agricultural field in three planting strategies: 20 small plugs, 4 medium-sized plugs, and a single large plug, with each treatment area totaling 0...
abstract different definitions have been proposed for soil quality. various soil properties have been suggetsted as soil quality indices by researchers. this research was conducted to study the relationship between slope of retention curve at its inflection point (s index) and other soil physical quality indices, because the reserches between s index and soil physical properties are little. thi...
This study aims to understand the spatial distribution of organic carbon and its sequestration potential in Tunisian soils. Soil organic carbon (SOC) stock was estimated in the 0-30 cm and to 0-100 cm soil depth for Tunisia using maps of soils and of the departments, combined with results from a soil database. The original soil classification was simplified to nine soils. Tunisia contains 24 go...
The objective of this study was to evaluate the effects of crop residues management on soil physical and biological properties. The impacts of residue management on yield of forage corn and barley and soil micro-organisms population were also studied. The results showed that application of crop residues increased soil organic matter (22.2 %), saturated hydraulic conductivity (51.9 %), porosity ...
The protection and improvement of natural resources especially for desert vegetation need a comprehensive recognition of natural resources and relationship on Soil characteristics. One of the most important species growing in sabzevar desert is Stipagrostis pennata and in the current research the relationship between the physicochemical properties of the soils and growth characteristics of the ...
Due to the feeding on prickly shrub of Astragalus adscendes by an insect (Cyamophila dicora Loginva), a kind of the manna named Gaz-angubin is produced which it’s harvesting has a long history in Isfahan province. This manna is exclusively produced in Isfahan, Iran. In this research, a map of spatial distribution of this prickly shrub was provided. By random-systematic sample of line transects,...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید