abstract in order to study the effects of salinity and silicon application on biomass of leaves and root of purslane (portulaca oleracea l.), a greenhouse experiment was conducted at research greenhouse of ferdowsi university of mashhad using completely randomized desgin with three replications. employed two factors consisted of three levels of salinity using nacl (0.6, 11, 22 ds/m) and two lev...

Added organic materials [1], composts and organic fertilisers are involved in building soil organic matter. They are a factor in soil property improvement, and can represent an important source of nutrients for both plants and soil organisms. Even a century ago [2], the composition of added organic materials was thought to have a direct influence on organic matter transformation. Intense work i...

introduction: soil organic matter is influenced strongly by vegetation cover and management, therefore it is proposed as the main indicator of soil quality and health. the changes in soil organic matter status occur much more rapidly in the labile pools than in organic c. thus, labile pools can be used as early indicators of changes in total organic matter that will become more obvious in the l...

The organic matter of soils is generally determined by converting it to carbon dioxide by means of moist and dry combustion. The carbon dioxide thus evolved is then calculated to organic matter by the use of a conventional factor, 0.471. It has been found, however, that the percentage of carbon in the organic matter of soils varies widely. Some doubt, therefore, is cast on the accuracy of the c...

Recent marine sediments from two cores, collected on the continental slope of the Nansha Sea, China, have been analyzed for organic matter content, n-alkane and isoprenoid hydrocarbons, fatty acids, n-alkanols and sterols. The organic carbon contents of the two sediment cores average 0.7 and 0.53%, respectively, and are higher than those of other sedimentary environments in this region. The dis...

The productive capacity of soils is directly associated with their organic matter content which is the main reservoir of organic carbon and main source of nutrients for plants (Grandy et al., 2006; Studdert et al. 1997; Sisti et al., 2004; Urquiaga et al., 2004). A sustained increase in the concentration of organic carbon is needed to establish a land management system where the degradation of ...

this study was conducted to determine the nutritive value of fresh and ensiled whole and partly stoned olive cake (oc) with or without molasses i.e., 0 and 50 gkg-1 on fresh basis. dry matter (dm), organic matter (om), crude protein (cp), neutral detergent fiber (ndf), acid detergent fiber (adf), lignin (sa), ether extract (ee), water soluble carbohydrates (wsc), and total phenols (tph) of all ...

the occurrence of soil water repellency and its intensity were studied in three sites under pinus teada, petrocarya fraxinifolia and sombucus ebulus in talesh township, western part of guilan province. seventy nine undisturbed soil samples from 0–5 cm depth were collected for water repellency and water-soil contact angle to be determined in a dry season. soil water repellency was assessed using...