博士 / 國立臺灣大學 / 農業化學系 / 84 / This research aims at the investigation of the soils that are
sampled from Shin-Yuan Shiang, a coastal area of Pingtung
county, which covers 4625 ha. Sampling points were designed
with spacing of 250 m and each point had ten layer taken from
different depths:0-5, 5-10, 10-20, 20-40, 40-60, 60-80, 80-100,
100-120, 120-140, and 140-150 cm. The soil samples had been
collected in the drought season of 1994. Statistical results
indicated that % of samples with EC >4 dS/m, as list orderly
from the top layer to the tenth layer, are: 25.3, 23.7, 16.0,
9.6, 6.9, 5.6, 4.4, 4.1, 3.1, and 4.05 %. Most salt accumulates
in 0-20 cm. SAR for all samples are <12, indicating the soils
in the area belong to saline soils, not sodic soils or saline-
sodic soils. In accordance with ion type, salt components can
be divided into two categories. If sodium is predominated in
soils, Cl would be >10 me/L, where Cl>NO3+SO4 and Na+K>Ca;
however, if calcium is predominated, then the following
conditions will occur: Cl-<NO3+SO4 and Na+K<Ca. Data as to
seventeen properties each layer for all sampling points were
subjected to the principle components analysis. There are
four groups of species in the layer of 0-5cm, for the first
two group have contribution to salinity, (1)EC,Mg,Na,Cl, Br,
exMg,and exNa: may brought in by sea water;(2)Ca,K,and NO3.
The principle components change with respect to depth. The
contour predicated by ordinary kriging shows that the space
distribution of Cl and Mg is similar to that of EC, but
narrower region; Cl and Mg are distributed mostly on the south-
south-west of area. NO3 is predominated spatially in the center
and north-west of the area, where some regions with high level
of NO3 are overlapped by that of high level EC. Space
distribution for Ca appear much random.
| Identifer | oai:union.ndltd.org:TW/084NTU00406007 |
| Date | January 1996 |
| Creators | Liao, Chiu-Jung, 廖秋榮 |
| Contributors | Houng, Kun-Huang, 洪崑煌 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 181 |
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