M. Renshaw et al., PREDICTING THE EFFECT OF ATMOSPHERIC-POLLUTION ON SOIL AND SURFACE-WATER ACIDIFICATION IN THE MIDDLE HILLS OF NEPAL, Science of the total environment, 208(1-2), 1997, pp. 71-79
Rapid population growth and the expansion of South East Asian economie
s have lead to recent concerns regarding the effects of anthropogenic
pollution on the environment. The RAINS-ASIA source-receptor, atmosphe
ric transport model, is used to produce scenarios of future anthropoge
nic sulphur deposition. This is used as an input to the MAGIC model fo
r prediction of future changes in the hydrochemistry of two catchments
of the Likhu Khola watershed in the Middle Hills region of Nepal. Sin
ce much of this region is under intense cultivation and the applicatio
n of mineral fertilisers may be contributing to soil and surface water
acidification and loss of soil fertility, a best-and worse-case scena
rio for fertiliser application are incorporated to assess the overall
anthropogenic influence upon soil and surface water acidification. The
results indicate a decrease of soil base saturation and streamwater A
NC, especially under the worst-case scenario of increased acidic depos
ition and increased fertiliser use. However, the pH status of soils an
d surface water are predicted to decrease only marginally as a result
of the abundant supply of base cations from the highly weathered bedro
ck and deep soil. The problem of increased acidification of soils and
water at a regional scale, however, should be addressed. (C) 1997 Else
vier Science B.V.