expansive soils undergo volumetric changes in response to changes in their moisture content that this characteristic causes irreparable problems particularly in civil projects. investigators have proposed chemical methods as well as mechanical treatments to stabilize the expansive soils. in this study, stabilization of expansive soil with randomly distributed fiber was investigated by reinforci...

hairy root systems are formed by transforming plant tissues with the “natural genetic engineer” agrobacterium rhizogenes. in most plants such as cichorium intybus l., hairy root cultures have proven to be an efficient system for secondary metabolites production. the effect of zinc (znso4), a heavy metal, was investigated at different concentrations (0, 1, 5 and 10 mm) on some secondary metaboli...

Soil compaction may affect N mineralization and the subsequent fate of N in agroecosystems. Laboratory incubation and field experiments were conducted to determine the effects of surface soil compaction on soil N mineralization in a claypan soil amended with poultry litter (i.e., Turkey excrement mixed with pine shavings as bedding). In a laboratory study, soil from the surface horizon of a Mex...

It is a fact that crops growth conditions vary greatly in the same field. Provisionally actual growth conditions are made up of many components, i.e. variation of natural conditions (climate & soil), results of effect of machinery on soil ( soil compaction) and unfavourable conditions for plant growing. In Estonia rather widely used ATV are causing remarkable damage to landscapes. All collected...

Most research on bioluminescent fungi is concentrated on their taxonomic relationships, while the basics of their natural history and ecological relationships are poorly understood. In this study, we compared the distribution of bioluminescent fungi between old-growth and secondary forest as related to four different soil types at the tropical rainforest of La Selva Biological Station in Costa ...

Digging by gophers disturbs near-surface soils, deposits sediment in mounds and “eskers” in non-uniform surface patterns, and affects surface penetrability of soils at alpine treeline. Soil samples were collected and soil compaction was measured at three sites in the Culebra Range of the Sangre de Cristo Mountains in southern Colorado, to determine the effects of gophers on surface compaction a...

Plant productivity is directly affected by the capacity of the root system to forage for soil resources. An enhanced understanding of root-soil interactions provides the potential to improve crop performance in specific soil environments. Interactions between roots and soil are, however, complex. The root-soil environment is heterogeneous and difficult to visualise and measure, root architectur...

Background: Purple coneflower (Echinacea purpurea L.) is one of the most important medicinal plants. Hairy root culture of Echinace, represent a valuable alternative to field cultivation for the production of bioactive secondary metabolites. Objective: The present study investigates the effects of KNO3, CaCl2 and MgSO4 concentrations on growth and the biosynthesis of cichoric acid in Echinacea...

-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...