Pesticide distribution and movement

摘要: Dpto. de Edafologia y Geologia, Universidad La Laguna, 30204, EspanaIntroductionThe first alarm signals with regardto the applicationofpesticides in agrosystems appeared late 50s andbecame more and evident 60s. However,the control of pests diseases is essential; globallosses world agricultural production have been esti-mated as up to one third total. Therefore, theuse pesticides modern agriculture, despite thenegative effects on environment, necessary.The study ground waters rel-atively new. The emphasis subject theUnites States began 1979 multiple detectionsof aldicarb [27] DBCP [14] water ofseveral states. By mid 80s, at least 17 pesticideshad found 23 states asa result field use. issue has addressed inother countries, particularly Canada, westernEurope [18].When contemplating vulnerability groundwater pesticides, three factors should be taken intoaccount: (i) properties pesticide itself affect-ing its mobility, (ii) dynamics inthe soil system (iii) movement pesticidethrough rocks that underly soil. These aspectsare detailed below.Properties affecting their mobilityThe term Pesticide currently used describe a widegroup substances or eliminateplant diseases. physicochemical fea-tures such variety compounds great, but theparameters useful dy-namics through soils aquifers are relatively few.Among them, following:Water solubilityThis parameter important because ve-hicle which move way theground water. If supposed poten-tially hazardous, it expected partiallysoluble However, this general rule beenshown not always true, some pesti-cides whose solubility low can reach thegroundwater association solid particles [26].The n-octanol:water partition coefficient (K