陡坡地逕流與滲漏水質之初步研究

PRELIMINARY STUDY OF RUNOFF AND PERCOLATION WATER QUALITIES ON STEEP SLOPING LAND

黃國禎(K. C. Huang) ； 黃俊德(C. T. Huang) ； 徐森雄(S. H. Hsu) ； 吳嘉俊(C. C. Wu)

《中華水土保持學報》 25卷2期 (1994/06) Pp. 83-93

https://doi.org/10.29417/JCSWC.199406_25(2).0003

摘要

本研究係選在屏東技術學院水土保持綜合示範區內陡坡地試驗區，進行試験研究；於1992年雨季（7〜9月）進行各試區地表逕流量、地表下渗漏量及土壤沖蝕量觀測。初步結果顯示滲漏計（Lysimeter）試區逕流量、沖蝕量及有關水質如SS、COD、TKN等均相對大於地表逕流觀測區。另由水質歷線得知水質中以COD及TKN最爲敏感，亦即在雨季初期卽大量洗出，並以吸著性（Adsorptive）成分爲主，往後則以水溶性爲主或兩者參半。金屬陽離子、陰離子之釋出及EC屬遲緩型，需待土壤環境離子游離潛能蓄積到一定程度，方發生大量同型取代而解離。水質中pH值之變動，主要與金屬陽離子及鹽類化合物之解離有關，而與降雨、逕流及沖蝕並無一定關係。滲漏計敷蓋區由於敷蓋資材分解效應，致使鈣、鉀、鈉離子洗出量遠大於其他試區。由鹼度及硬度兩項指標可判斷出各試區在雨季初期，水中硬度兼含碳酸式及非碳酸式；而在雨季中期則以碳酸式爲主；此與硫酸鹽等鹽類歷線濃峰出現期相符。另從滲漏計滲漏水連續採樣分析結果，發現各項水質未見與降雨、逕流及沖蝕存有一定關係。如寶莉及歐瑪颱風連續之水樣水質中，以鉀離子爲例，上一次呈正相關，另次連續降雨卻呈負相關。

關鍵字

滲漏計 ； 水質 ； 溶質

並列摘要

All experiments of this study were conducted on the steep sloping experimental site of National Pingtung Polytechnic Institute. Runoff, percolation, soil erosion as well as water samples for water quality analysis were observed and taken from July to September, 1992. Preliminary results indicated that the amount of runoff, erosion, and some water quality related indices like SS, COD, and TKN from lysimeter plot were greater than those from surface runoff observed plots due to finer soil texture and lesser gravel content. From the chemographs of water quality analysis, COD and TKN were found leaching in an adsorptive form during the early stage of rain season. Cation and anion would be released significantly as the potential of ionic activity reached its capacity to encourage the occurence of ion exchange and isomorphous substitution. Because of the characteristics of ions, the variation of pH value was chaotic. The effluents of calcium, potassium and sodium from mulching plot were found higher than that from other plots, which could be possibly due to the degradation of mulching material. In the early stage of rain season, hardness had the same contituents of carbonates as noncarbonates, but in the middle stage the major contituent was carbonates. From the continuous sampling of percolation water, analytical results indicated that all the water qualities did not show any determinative relationships with rainfall, runoff and erosion.

並列關鍵字

Lysimeter ； Water Quality ； Solute