The high diversity of tree species has traditionally been considered an important controller of belowground processes in tropical rainforests. However, soil water availability and resources are also primary regulators of soil bacteria in many ecosystems. Separating the effects of these biotic and abiotic factors in the tropics is challenging because of their high spatial and temporal heterogene...

One application, only in-situ soil mixing (or deep mixing method, DMM) is becoming increasingly common as an economical construction method for temporary support of deep foundation excavations and is also used in the construction of permanent retaining walls. Steel beams placed into the fresh soil/cement are generally used as the primary structural support, later supplemented with bracing or ti...

Heterogeneity in hydraulic, physical and chemical properties of porous media can not only limit microbial dispersion but may also complicate the quantification of microbial transport processes and resultant microbial activities. The objectives of this research were to determine the potential for bacterial transport through an unsaturated soil block under transient flow conditions and to determi...

Biodynamic farming practices show promise in mitigating some of the adverse effects of conventional agriculture on the environment. Biodynamic farming is like organic farming in that no synthetic chemical fertilizers and pesticides are used. Unlike organic farmers, biodynamic farmers add eight specific preparations (made from cow manure, silica, and various plants) to enhance soil quality and p...

Soil–structure interaction problems are commonly encountered in engineering practice, and the resulting linear systems of equations are difficult to solve due to the significant material stiffness contrast. In this study, a novel partitioned block preconditioner in conjunction with the Krylov subspace iterative method symmetric quasiminimal residual is proposed to solve such linear equations. T...

abstract irrigation planning and management requires continious monitoring and measurements of soil moisture content. application of gypsum blockes (gb) are common in soil moisture measurements. gb readings are subjected to its geometry and soil solution concentration. this study was carried on 90 gb in research greenhouse of faculty agricultural, ferdowsi university of mashhad. at the begining...

BACKGROUND: While recognizing the economic obstacles that currently block widespread use, many concerned with improving agricultural productivity and food security in Sub-Saharan Africa (SSA) are focusing on fertilizer as a remedy for declining soil quality and stagnant yields. Some have suggested that SSA needs to increase fertilizer use from 9 to at least 30 kg/ha during the next decade. Othe...

Collapsible soils could widely be found in central part of Iran and has caused lots of problems for roads and railroads in that region. Appearance of wide cracks in the collapsible soil near the Tehran-Semnan railroad tracks has caused some worries regarding the safety and performance of the railroad. However, due to the high traffic of the railroad, it is impossible to block the road for remed...

Abstract Deep soil mixing method (DSM) is a novel in situ technology improvement which different cementitious materials are mixed with and form soil-cement column improved engineering characteristics. Due to the configurations of these columns, types DSM formed, such as wall type, grid block etc. expansion construction massive industrial structures, use type control settlements has grown. In or...