結合地理資訊系統之溶質移動模式評估區域尺度下農藥在土壤中之動態

Linking a Geographic Information System with a Solute Transport Model for the Regional-Scale Assessment of Fate of Pesticides in Soils

陳吉村 ； 李達源

《土壤與環境》 1卷4期 (1998/12) Pp. 325-332

https://doi.org/10.30058/SE.199812.0005

摘要

本研究以一個和地理資訊系統（GIS，MapInfo）相結合之溶質移動模式（CMLS94）來模擬農藥在台灣十二個代表性土系土壤中之動態。透過GIS和CMLS94間之介面程式，使用者只要在螢幕上以游標點選取欲模擬之土系，介面程式即可透過GIS之空間查詢功能，將儲存於GIS資料庫之土壤資料及經過距離分析所得最近的測候站的氣象資料傳送至溶質移動模式中， 供使用者利用CMLS94所提供308種農藥參數進行農藥在土壤中動態之模擬。本文以模擬三種常用農藥2,4-D Dimethylamine salt、Carbofuran及Methomyl在臺灣十二個土系土壤中之動態為例，說明此結合系統之功能。此例中假設這三種農藥於1981年1月1日施用於栽種玉米（假設根深為60公分）之土壤表面，不作人為灌溉，模擬農藥移動的深度及其殘留量隨時間之變化，評估這些農藥污染地下水之可能性。結果顯示2,4-D Dimethylamine salt和Carbofuran在這十二個土系土壤移動到達地下水位所需的時間較Methomyl短。而到達地下水位時農藥之殘留量（以相對於原始施用量之百分率表示），Carbofuran的殘留百分率大於2,4-D Dimethylamine salt和Methomyl。其中在壯圍系土壤，因其地下水位僅距地表18cm，Carbofuran只要58天即可到達地下水位，且其殘留百分率還有45%，所以污染地下水的可能性高，必須特別加以注意。此系統之建立，可供篩選與初步評估台灣地區農藥污染土壤與地下水之可能性，然模擬結果尚待臺灣地區之田間實際觀測資料予於驗證。

關鍵字

地理資訊系統 ； 溶質移動模擬 ； 農藥 ； 地下水污染

並列摘要

In this study, a GIS (MapInfo) coupled with a solute transport model (CMLS 94) was used to simulate the fate of pesticides in 12 representative soil series of Taiwan. Through the interface program between the GIS and the CMLS 94, users can select the soil series needed for assessment by the cursor click to retrieve soil data and weather data of the nearest weather station from the GIS to the solute transport model for simulating the fate of 308 pesticides, whose properties were provided by the CMLS 94, in these soils.An example using the weather data of 1981 to 1990 from the 12 stations of the Central Weather Bureau, assuming no irrigation and that pesticides were applied on the soil surface to simulate the fate of pesticides in corn fields which were assumed to have a root zone of 60 cm in depth, was presented. In this example, the time needed for three pesticides, including 2,4-D Dimethylamine salt, Carbofuran, and Methomyl, to reach the water table of the 12 representative soil series of Taiwan was assessed. The results showed that the time needed for 2,4-D Dimethylamine salt and Carbofuran was shorter than that for Methomyl. The results also indicated that the residual percentages of Carbofuran when reaching the water table of the 12 representative soil series were higher than those of 2,4-D dimethylamine salt and Methomyl. From the resluts of simulation, we found that the time needed for Carbofuran to reach the water table of Chuangwei soil series, which is 18 cm below the soil surface, was only 58 days and that the residual percentage was 45%. Therefore, the potential of groundwater pollution resulting from the application of Carbofuran in this area is high and should be cautioned. The established system can be used in Taiwan for screening and preliminary evaluating the possibility of soil and groundwater contamination by pesticides. However, further validation of the system using the field observed data of Taiwan is needed.

並列關鍵字

Geographic information system(GIS) ； Solute transport modeling ； Pesticide ； Groundwater pollution