以微形態學探討南仁山區熱帶森林土壤之化育作用
Other Title
Using Micromorphology to Interpret the Genesis of Tropical Forest Solis in the Nanjenshan Area of Taiwan
Journal
臺灣林業科學
Journal Volume
16卷
Journal Volume
16
Journal Issue
1期
Journal Issue
1
Pages
25-38
Start Page
25
End Page
38
ISSN
10264469
Date Issued
2001-03
Author(s)
Abstract
本研究在墾丁國家公園內的南仁山長期生態研究站，選擇萬里得山與南仁山兩個地形序列，在山頂、背坡與麓坡處分別選擇一代表性土壤剖面共計六個，以微形態學探討粘粒在土壤中的移動與聚積，並解釋此熱帶森林土壤的化育作用模式。研究結果指出，萬里得山地形穩定，其W-1、W-2及W-3土壤樣體厚度均超過2m，分類上為厚育濕潤極育土，微形態特徵顯示其Bt層中的粘粒除了來自洗入作用外，現地風化作用是土壤中粘粒增加的最主要來源。洗入型的粘粒呈有順序的堆積而成為具有良好定位排列的粘粒膜，但現地風化型的粘粒則不具定位性。南仁山地形序列中山頂之N-1樣體，其微形態特徵及化育過程皆與萬里得山土壤類似，但在背坡與趾坡的N-2與N-3樣體則為低鹽基濕潤弱育土，土壤微形態特徵顯示只有微弱的構造發育與風化的原生礦物，並無其他土壤化育特徵。在南仁山長期生態研究站的兩樣區土壤化育作用模式為，在穩定的地形、高溫多雨、乾濕交替作用的環境條件下，又有良好的植被覆蓋，則會形成具有高含量粘粒的極育土；但在地形不穩定時由於地形位置與坡度的變化，造成水分淋洗作用較弱，使土壤化育程度較弱而僅生成弱育土。
At the Nanjaishan long-term ecological research (LTER) site of Kenting National Park in southern Taiwan, 6 soil pedons were selected from the summit, backslope, and footslope positions along the Wanliteshan and Nanjenshan toposequences. The objectives of this study are to describe the soil micromorphological characteristics as well as to interpret clay accumulation and the pedogenic processes of tropical forest soils. The results indicate that 3 soil pedons at the Wanliteshan toposequence are classified as Paleudults. Clay accumulations in their Bt horizons were from illuviation and in situ weathering, with the latter being the major source. The illuvial clay with well-oriented arrangement showed as clay coatings, but in situ weathered clay did not show the orientation arrangement. The micromorphological characteristics and genetic process of the soils at the summit position in the Nanjenshan toposequence are similar to these of Wanliteshan. But the soils in the N-2 pedon at the backslope and the N-3 pedon at the toeslope, classified as Dystrudepts, only showed weak microstructural development and altered primary minerals. The pedogenic processes in the study area within the LTER site are proposed as follows: Ultisols forming association with high clay content in the stable landscape, high temperature and precipitation, alternating wet and dry cycles, and good vegetation cover. In the unstable landscape associated with steep slopes, the soils have only developed as Inceptisols through weak leaching processes.
Subjects
長期生態研究
地形序列
微形態學
粘粒膜
土壤化育作用
long-term ecological research (LTER)
toposequence
micromorphology
clay coating
soil genesis
Publisher
農業部林業試驗所
Type
journal article