An equation was constructed to estimate the stem volume of Norway spruce (Picea abies (L.) Karst.) in 145 stands growing on former farmland in Sweden (Latitude 56–63° N). The mean total age was 40 ± 13 (range 17–91) years, the mean diameter at breast height (ob) was 15 ± 4 (range 5–27) cm and the mean density was 1621 ± 902 (range 100–7600) stems ha. The equation which fits the data best used t...

Various soil texture schemes are in current use. These differ in the size ranges of their particle fractions. There is a need to establish simple methods to correlate these conventional schemes. Therefore I have defined closed-form exponential and power law functions to fit models to cumulative particle-size distribution data. I have tested the functions for their suitability (i) to represent c...

Geotextiles have been commonly used in geotechnical and environmental engineering projects to prevent erosion of soils in contact with the filter without impeding the flow of seeping water through the soil. Several empirical criteria incorporating varying factors of safety have been proposed for selection of geotextile filters. A probabilistic numerical filter model, named RETAIN, using image-b...

The effect of carbonation on a one-year atmospherically exposed lime-treated soil structure is investigated. investigation involves analyzing the chemical characteristics and pore-structure modifications several specimens sampled up to 12 cm depth perpendicular surface. On comparing analysis with untreated core-sampled specimens, found have occurred 4.2 decrease in pH value 9 or lower than that...

We investigated the effects of various factors (brij 30, brij 35, yeast extract, hydrogen peroxide and compost) on the aerobic degradation of nonylphenol (NP) in soil and characterized the structure of the microbial community in that soil. Residues of NP were measured using gas chromatography-mass spectrometry (GC-MS) and a change of microbial communities was demonstrated using denaturing gradi...

Water vapor diffusion through the soil is an important part in the total water flux in the unsaturated zone of arid or semiarid regions and has several significant agricultural and engineering applications because soil moisture contents near the surface are relatively low. Water vapor diffusing through dry soil is absorbed for both long and short terms. Long-term absorption allows more water to...

The genesis of some types of patterned ground, including hummocks, frost boils and sorted stone circles, has been attributed to differential frost heave (DFH). However, a theoretical model that adequately describes DFH has yet to be developed and validated. In this paper, we present a mathematical model for the initiation of DFH, and discuss how variations in physical (i.e. soil/vegetation prop...

polycyclic aromatic hydrocarbons are a class of potentially hazardous chemicals of environmental and health concern. pahs are one of the most prevalent groups of contaminants found in soil. biodegradation of complex hydrocarbon usually requires the cooperation of more than single specie. in this research biotreatment of pah (phenanthrene) was studied in a solid-phase reactor using indigenous ba...

The effects on hydromechanical performance due to chemical interactions between pore solution and soil components in lime-treated are investigated. Static- kneading-compacted soils percolated by demineralized water (DW) a low-ionic strength solution. Kneading action causes aggregate deformation, thus consequently reducing macropores of diameter 105 Å. This increases the hydraulic tortuosity len...