02-10-2010, 10:07 AM
Prepared by:
Dr. M. Dhakshinamoorthy
Professor of Soil Science & Agricultural Chemistry
Abstract
Soil quality and water quality are concepts related with the functions of these natural resources withinthe environment. Indicators and indexes can be linked with standards for the multiple uses of theseresources and can be used as guides for land use and land management planning, from the field to thewatershed levels. The design of a resource management system must accomplish the standards fixedfor one or more particular resource uses. Vetiver grass technology (VGT) must be designed keeping inmind this requirement. Experimental data from erosion plots, under natural and simulated rainfall, areused to exemplify how VGT helps maintain soil and water quality. Sediment loads are reduced up to90% in plots with vetiver grass hedgerows compared with those without cover and vetiver hedgerows.Organic matter loads are reduced up to 57% and total P up to 70%. Loads of highly soluble elementslike calcium are not significantly reduced. When VGT is combined with another technology, likeresidue management, risks of failure are diminished. Some indexes like the soil productivity index‘IP’, soil loss tolerance ‘T’ and ‘CP’ factors (USLE) are used to illustrate design procedures to useVGT in agricultural systems. The advantages of using simulation models and the need for soil andwater quality monitoring, at field and watershed levels, are briefly discussed in the realm of naturalresource planning and management. An international effort to supply less developed countries, mainlyin tropical areas, with these tools and procedures will help reach higher soil and water quality
Dr. M. Dhakshinamoorthy
Professor of Soil Science & Agricultural Chemistry
Abstract
Soil quality and water quality are concepts related with the functions of these natural resources withinthe environment. Indicators and indexes can be linked with standards for the multiple uses of theseresources and can be used as guides for land use and land management planning, from the field to thewatershed levels. The design of a resource management system must accomplish the standards fixedfor one or more particular resource uses. Vetiver grass technology (VGT) must be designed keeping inmind this requirement. Experimental data from erosion plots, under natural and simulated rainfall, areused to exemplify how VGT helps maintain soil and water quality. Sediment loads are reduced up to90% in plots with vetiver grass hedgerows compared with those without cover and vetiver hedgerows.Organic matter loads are reduced up to 57% and total P up to 70%. Loads of highly soluble elementslike calcium are not significantly reduced. When VGT is combined with another technology, likeresidue management, risks of failure are diminished. Some indexes like the soil productivity index‘IP’, soil loss tolerance ‘T’ and ‘CP’ factors (USLE) are used to illustrate design procedures to useVGT in agricultural systems. The advantages of using simulation models and the need for soil andwater quality monitoring, at field and watershed levels, are briefly discussed in the realm of naturalresource planning and management. An international effort to supply less developed countries, mainlyin tropical areas, with these tools and procedures will help reach higher soil and water quality
:K: 4:2:1) has resulted in ration of N