نتایج جستجو برای: soil density
تعداد نتایج: 583021 فیلتر نتایج به سال:
-Compaction is one of the efficient ways to improve the strength and stiffness properties of soils, such as elasticity modulus and shear modulus. Moreover, compaction decreases soil settlement, improves bearing capacity and the stability of sloped embankments. An optimum water content is required to provide the best path to enter energy into soil and compact it. A constant value of energy appli...
The results of field survey, germination and correspondence analysis showed that the soil seed banks density ranged from 900 to 6,467 seeds m at 0-5 cm depth and 117 to 2,467 seeds m at 5-10 cm depth, with species richness of 7-14. Early successional species dominated the soil seed bank, while later successional species occurred only at low density. The similarity between soil seed bank and sta...
Host legumes can enrich their immediate soil environment with rhizobia through rhizosphere effects. The extent to which this enrichment occurs, the specificity of the process and its interaction with soil management factors remain poorly described. In a series of field trials, we measured changes in the size of indigenous populations of Bradyrhizobium in response to cropping of host and non-hos...
Arbuscular mycorrhizal fungi (AMF) play major roles in nutrient acquisition by crops and are key actors of agroecosystems productivity. However, agricultural practices can have deleterious effects on plant–fungi symbiosis establishment in soils, thus inhibiting its potential benefits on plant growth and development. Therefore, we have studied the impact of different soil management techniques, ...
BACKGROUND: Application of plant mulches plays a significant role in development and expansion of sustainable farming systems. OBJECTIVES: Assessment effect of chemical and non-chemical weeds management methods on weeds density and biomass and the properties of soil, including microbial biomass carbon (MBC) and soil organic carbon (SOC) in potato cultivation. ...
Three advanced technologies to measure soil carbon (C) density (g C m(-2)) are deployed in the field and the results compared against those obtained by the dry combustion (DC) method. The advanced methods are: a) Laser Induced Breakdown Spectroscopy (LIBS), b) Diffuse Reflectance Fourier Transform Infrared Spectroscopy (DRIFTS), and c) Inelastic Neutron Scattering (INS). The measurements and so...
Restoring biological soil crusts (biocrusts) in degraded drylands can contribute to recovery of ecosystem functions that have global implications, including erosion resistance and nutrient cycling. To examine techniques for restoring biocrusts, we conducted a replicated, factorial experiment on recently abandoned road surfaces by applying biocrust inoculation (salvaged and stored dry for two ye...
Algorithms for estimating dry snow density and the dielectric constant and roughness of the underlying soil or rock use backscattering measurements with VV and HH polarization at L-band frequency (1.25 GHz). Comparison with field measurements of snow density during the first SIR-C/X-SAR overpass shows absolute accuracy of 42 kg m 3 (13% relative error). For the underlying soil, comparisons with...
one of the important aspects of soil is, knowing the relationships between spatial features of soil and quantity in statistical model. the goal of this research is to estimate saturated hydraulic conductivity by regression and co-active neuro-fuzzy inference system (anfis) with using the parameters of bulk density, real density, porosity, fractal dimension of particle size, and clay percent, si...
Several methods for dispersion of soil were tested for possible use in procedures for extraction of bacteria. Physical cell damage on cells and efficiency in extraction of indigenous cells from soil, were investigated. Cell damage by the dispersion methods was investigated by measuring the physical cell integrity and viability of pure cultures of Escherichiu coli and Bacillus subtilis, as well ...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید