ISPRS, Vol.34, Part 2W2, “Dynamic and Multi-Dimensional GIS”, Bangkok, May 23-25, 2001 
37 
•ation using least- 
1 of Geographical 
5). RS-GIS: spatial 
i, P. and Batty, M., 
nent. John Wiley & 
INTEGRATION OF GIS WITH PESTICIDES LOSSES RUNOFF MODEL 
Bing CHEN 1 , Gordon HUANG 1 , Jonathan LI 2 , Yueren LI 1 , and Yifan LI 3 
mational Journal of 
1 Environmental System Engineering Program, Faculty of Engineering, University of Regina, Regina, SK S4S 0A2, Canada 
(1992). Category 
s in an integrated 
lation system, 
Sensing, 58, pp. 
Tel: (306) 585-5631, Fax: (306) 585-4095, E-mail: {chenbing, gordon.huang, liyuerU} @uregina.ca 
2 Department of Geography, University of Regina, Regina, SK S4S 0A2 Canada 
E. (1995). Forest 
California, using 
formation system. 
nsing, 61, pp. 299- 
Tel: (306) 585-5273, Fax: (306) 585-4815, E-mail: jun.li@uregina.ca 
3 Atmospheric Environment Service, Environment Canada, Downsview, ON M3H 5T4, Canada 
Tel: (416) 739-4892, Fax: (416) 739-4288, E-mail: yi-fan.li@ec.gc.ca 
KEYWORDS: Pesticides, GIS, terrain analysis, pollution, runoff model. 
ABSTRACT 
Pesticides pollution is derived from agricultural activities on broad and diffuse location. The pollution is often a gradual and subtle hazard 
and the extent of pollution is affected by uncontrollable events, such as storms as well as geographic and geologic conditions. The 
development of spatial models incorporating remote sensing data sets and GIS software provides a useful tool. In this paper, an 
integration approach of GIS and remote sensing with pesticides losses runoff model is proposed. A set of terrain analysis methods is 
applied to compute the slope, direction flow and contributing area, etc. The DEM generated from aerial photographs is used to compute 
hydrological parameters for the pesticides model. Cell numbers, cell connectivity, flow directions, land and channel slopes, slope lengths, 
slope shapes, and upslope contributing areas, are carried out. Although they are only some of results derived from an ongoing project, the 
results have proved that the feasibility and utility of interfacing terrain analysis technique with existing pesticides losses runoff models. By 
using the capabilities of terrain analysis in modeling processes directly impacted by terrain characteristics, a more realistic description of 
these processes is possible. The paper concludes by briefly analyzing the advantages of integration of pesticides pollution model with GIS 
application. 
(1991) reported that, nationally, 5% of fish kills were caused by 
INTRODUCTION pesticides in USA. 
The use of pesticides is widely accepted as indispensable in 
most agricultural systems. However, there has been growing 
concern about the fate of chemicals leaving the field and which 
are threatening water quality in the past decades. This kind of 
nonpoint source pollution is often a gradual and subtle hazard 
to the environment. This is because the chemicals applied as 
both herbicides and pesticides are long-lived, and can be 
transported by water. Because of their severe toxicity, most of 
these compounds have been banned or restricted from 
extensive uses (Heidi and Jeff, 1994). However, many other 
pesticides, especially herbicides, remain in use as essential 
chemicals in modern agriculture, which has spanned a wide 
range of research efforts on their behavioral and toxicological 
properties. Among all the herbicides, alachlor, atrazine, 
cyanazine and metolachlor account for about 73% of the 
pesticides applied (Gianessi and Puffer, 1991). As water runoff 
moves over the land, pesticides resulting from agricultural 
activity are picked up and deposited into rivers, lakes, and other 
bodies of water. Pollutants dissolved in the runoff are generally 
more biologically available in water bodies than 
sediment-based fractions and can be potentially more harmful 
(DEC, 1990). It affects human health, quality of life, economic 
smooth activities, and recreation, as well as the survival of fish 
and wildlife and ecosystems integral to natural resource 
preservation (Floyd et. al., 1998). For example, Lowe et al. 
Pesticides pollution are derived from agricultural activities on 
broad and diffuse location, the pollution sources are difficult to 
identify. The discharges from them enter surface waters in a 
diffuse manner and at intermittent intervals and travel over land 
before reaching surface waters. The extent of the pollution is 
affected by uncontrollable events, such as storms as well as 
geographic, geologic and hydrological conditions, and may 
differ greatly from place to place and year to year. The 
governments of many countries have targeted the identification 
and control of pesticides losses as a major goal for pollution 
abatement. In order to develop plans to assess, manage, and 
reduce pesticides remains in waters where water quality 
problems have been identified. Remote sensing and 
geographic information system (GIS) can aid in rapid inventory 
and assessment of regions for potential pesticides pollution 
problems. Because surface runoff in agricultural areas 
contributes heavily to pesticides pollution, one way to 
implement such a management program is to focus on the 
characteristics and conditions of surface runoff. But, to control 
and monitor these problems, it is necessary to know what the 
current areas of concern, often at the parcel level (Floyd et. al, 
1998). 
The development of spatial models incorporating remote 
sensing data sets and GIS software provides a useful tool, not 
only for depiction of past and current pesticides losses, but also