ABSTRACT
A simple method is given for forecasting the reaction under different soil and site conditions of 106 pesticides with known binding strength by humus and clay in relation to pH and with known volatility and aerobic and anaerobic degradability. The method is based on easy-to-determine soil characteristics (texture, humus content, pH, groundwater table) and meteorological data (mean temperature, climatic water balance). It is possible to use this method to predict the environmental risk, especially the risk of contamination, and the groundwater pollution potential of a particular pesticide for a particular site in the field. In addition, recommendations for food contamination are given. This simple approach is suitable for use in on-site consultations. A reduction in pesticide input into near-surface groundwater can be expected when the recommendations derived from the model are applied. The use of this pragmatic model by farmers increases the awareness of the vulnerability of the groundwater recourse.
Subject(s)
Forecasting/methods , Models, Biological , Pesticides/pharmacokinetics , Soil Pollutants/pharmacokinetics , Water Pollution, Chemical/analysis , Adsorption , Biodegradation, Environmental , Risk Factors , VolatilizationABSTRACT
Binding and retention against uptake by plants, and groundwater pollution of the metal ions Cd, Mn, Ni, Co, Zn, Cu, Cr(III), Pb, Hg, Fe(III), and Al by soils in relation to pH, redox potential, texture, organic matter, and iron oxide contents can be diagnosed in the form of rough relative values with simple field methods. A comparison with the results of some pot and field trials showed the practicability of this method.
Subject(s)
Metals/chemistry , Soil Pollutants/analysis , Soil/analysis , Aluminum Silicates/analysis , Clay , Copper/chemistry , Hydrogen-Ion Concentration , Oxides/chemistry , Plants/metabolism , Water/chemistry , Water Pollutants, Chemical/analysis , Water Supply/analysis , Zinc/chemistryABSTRACT
The behavior of linear alkylbenzenesulfonate (LAS) in soils (i.e., degradation, percolation, and sorption) was investigated in field and laboratory tests. For this purpose sorption studies were carried out using Freundlich's method in order to obtain sorption constants. A prediction of sorption constants in characterized soils was possible using multiple regression and correlation methods. Degradation under laboratory conditions can faithfully be used for the interpretation of degradation times under field conditions. In laboratory tests LAS has reacted immobilely as in field tests. The uptake of LAS in plants is very high; however, it is slowly metabolized.
Subject(s)
Alkanesulfonates/analysis , Alkanesulfonic Acids , Soil Pollutants/analysis , Half-Life , Lolium/analysis , Plants/analysisABSTRACT
Sorption, movement, and decomposition of trichlorphenoxyacetic acid (2,4,5-T) in two Berlin soils were investigated in field experiments in summer and winter time. Contemporary with simple laboratory methods, it was attempted to predict the behavior under field conditions. For this purpose, adsorption and desorption experiments were carried out and isotherms were calculated using the Freundlich equation. Second, percolation studies under saturated and unsaturated conditions were considered. Finally, the decomposition of 2,4,5-T in soil samples at different temperature was determined. A sorption experiment at the beginning of a test program for prediction the behavior from chemical compounds at least with four soil samples, a Chernozem-Ah, a Cambisol-Ap, a Podsol Ah, and a Pelosol-B, completed by decomposition experiments measuring the CO2-respiration, is proposed.