Pesticide runoff

Pesticide Runoff Modeling. Obtaining the field data necessary to understand the potential mnoff of pesticides under a variety of conditions and sods would be an expensive and time-consuming process. As a result, a variety of simulation models that vary in their conceptual approach and degree of complexity have been developed. Models are influenced by their intended purpose, the biases of the developer, and the scale at which they are used. 

Dinitrophenol is a member of the aromatic family of pesticides, many of which exhibit insecticide and fungicide activity. DNP is considered to be highly toxic to humans, with a lethal oral dose of 14 to 43mg/kg. Environmental exposure to DNP occurs primarily from pesticide runoff to water. DNP is used as a pesticide, wood preservative, and in the manufacture of dyes. DNP is an uncoupler, or has the ability to separate the flow of electrons and the pumping of ions for ATP synthesis. This means that the energy from electron transfer cannot be used for ATP synthesis [75,77]. The mechanism of action of DNP is believed to inhibit the formation of ATP by uncoupling oxidative phosphorylation. 

Frequency domain performance has been analyzed with goodness-of-fit tests such as the Chi-square, Kolmogorov-Smirnov, and Wilcoxon Rank Sum tests. The studies by Young and Alward (14) and Hartigan et. al. (J 3) demonstrate the use of these tests for pesticide runoff and large-scale river basin modeling efforts, respectively, in conjunction with the paired-data tests. James and Burges ( 1 6 ) discuss the use of the above statistics and some additional tests in both the calibration and verification phases of model validation. They also discuss methods of data analysis for detection of errors this last topic needs additional research in order to consider uncertainties in the data which provide both the model input and the output to which model predictions are compared. 

The automated pesticide runoff model consists of a set of FORTRAN programs which calculate the amount of pesticide runoff from input of river basin data, rainfall data, pesticide characteristics, and application data. Table I shows the input requirements for the SWRRB model. Table II shows the output data from the SWRBB model. 

Average monthly and annual values for pesticide runoff... 

Carsel, R. F. Pesticide Runoff Simulator User s Manual, Computer Sciences Corporation, 1980. 

Despite the strengthening of environmental policies, problems in relation to cadmium and cyanide, dioxin, organic pollution, lake eutrophication, residential sewage, pesticide runoff, industrial discharges, and groundwater contamination by toxics and nitrates also need to be tackled. 

Sudo, M. and T. Kunimatsu (1992). Characteristics of pesticides runoff from golf links. Wat. Sci. Technol., 25 85-92. 

Fawcett, R.S., B.R. Christensen, and D.P. Tierney (1994). The impact of conservation tillage on pesticide runoff into surface water A review and analysis. J. Soil Water Conserv., 49(2) 126-135. 

Much of the ability of conservation tillage to reduce runoff of pesticides such as the triazines is related to increases in water infiltration due to improved soil structure and slowed water runoff. However, if water infiltration is prevented by a high water table or restrictions to permeability such as claypans, conservation tillage may not reduce pesticide runoff. 

Rachel said, That is a very interesting idea. Overall, I am excited about the possibility of using GE as a tool to reduce toxic pesticide runoff into streams. Water quality is an important issue for me. The others are not so enthusiastic. Craig paused and then said, I don t know what to think about GE. ... 

Di Guardo, A., Calamari, D., Zanin, G., Consalter, A., Mackay, D. (1994) A fugacity model of pesticide runoff to surface water development and validation. Chemosphere 28, 511-531. 

Pesticide runoff may harm fish and other aquatic animals and plants in ponds, streams, and lakes. Aquatic life also can be harmed by careless tank... 

One of the first complete, continuous simulation models was the pesticide runoff transport model (PRT) (56). Improvements in the PRT modelled to the hydrologic simulation program—FORTRAN model (57). A number of other models have been developed (58,59). These models represent a compromise between the avadable data and the abiHty to encompass a wide range in soils, climates, and pesticides. These models have had mixed success when extended beyond the data with which they were caHbrated. No model has yet been developed that can be proven to give accurate predictions of... 

Haith DA. TurfPQ, A Pesticide Runoff Model for Turf. J Environ Qual 2001 30 1033-9. 

Competitive ion displacement can represent an important means by which arsenic is released to the aqueous phase, where it is subject to transport. Displacement and mobilization of As by phosphates is of particular concern (Manning and Goldberg, 1996 Reynolds et al., 1999 Violante and Pigna, 2002 Dixit and Hering, 2003), and regions where fertilizer or pesticide runoff and leaching... 

EXPOSURE ROUTES Inhalation (vapors) ingestion (contaminated water from pesticide runoff) absorption occupational exposure. 

EXPOSURE ROUTES primarily from pesticide runoff to water readily adsorbed through intact skin vapors adsorbed through respiratory tract automobile exhaust gas... 

Besides, the pesticide runoff is the main process that can contaminate the surface watet It occurs if the rainfall events prevail on the soil absorpdon. The acdve surface soil depth that interacts with runoff is about 2-10 mm. Surface water also can be contaminated directly by pesdcides by the ddft caused by pesticide application. 

Probabilistic risk assessment through pesticide fate modeling for evaluating management practices to prevent pesticide runoff from paddy fields (S. H. Vu, Tokyo Univ. of Agric. Tech., Japan)... 

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