宜蘭南澳地區海岸防風林土壤性質的空間變化

Spatial Variability of Soil Characteristics in Coastal Windbreak in Nanao Area, Ilan

張瑀芳(Yu-Fang Chang) ； 蔡呈奇(Chen-Chi Tsai)

《宜蘭大學生物資源學刊》 5卷1期 (2009/06) Pp. 29-39

https://doi.org/10.6175/job.2009.51.14

摘要

本試驗地位於宜蘭縣南澳溪河口以南、澳尾山以北之海岸防風林，因長期受到東北季風以及颱風的影響，目前防風林破壞程度已相當嚴重。本研究的主要目的為藉由該林分土壤理化性質的分析，探討該海岸防風林下土壤性質的空間變化，並提出建議。研究指出防風林的土壤多屬於輕度與中等鹼性土壤（pH 7.4～8.4），愈靠近海邊土壤的pH值愈高。土壤電導度值（EC）大都在2～4 dS/m之間，屬於微鹽性土。土壤有機碳含量大都小於1%，包括可交換性鹽基、陽離子交換容量與鹽基飽和度的含量都說明了本研究區的土壤相當的貧瘠。近海樣點的交換性鈉百分比值相對較高，但值都小於1%，顯示土壤中沒有鈉離子的聚積。交換性鈉百分比與鈉吸附比兩者的結果皆說明了該防風林地上部植物的生長不會受到土壤中鈉離子的危害。研究區土壤pH值與EC值普遍有偏高的現象，建議未來復育時能多考量植物的生理特性，多選擇耐鹽性的樹種；研究區土壤有機碳含量極低，建議可以在研究區中每年多次鋪上大量纖維質含量較高的農業廢棄物，先改善土壤的物理性質，再進一步改善土壤的肥力性質，以提供地被植物較多的養份。

關鍵字

南澳地區 ； 海岸防風林 ； 土壤性質 ； 空間變化

並列摘要

The coastal windbreak of this study is located at between southern Nanao Creek and northern Aoweishan. The stand structure of this windbreak was destroyed seriously by long-term effects of northeastern monsoon and typhoon. The objectives of this study were to examine the spatial variability of soil characteristics of this windbreak by soil physical and chemical analysis and to propose suggestions for stand management. The results indicated that based on the soil pH the soil under the coastal windbreak was classified as mildly ~moderately alkaline soil (pH 7.4~8.4). Also the soil pH was higher as the soil near the seacoast. The soil EC value was ranged from 2 to 4 dS/m and could classified as slightly saline soil. The soil organic carbon content was mostly less than 1%. The content of exchangeable bases, cation exchange capacity and base saturation percentage also suggested that the soil of this study site was very poor. The relatively higher ESP value was found in soils near seacoast, but mostly the ESP value was less than 1% suggested that no sodium was accumulated in soils. The results of ESP and SAR both indicated that plant growth on the windbreak can not be damaged in situ by the sodium ion from soils. According to the generally higher soil pH and EC of this study site, we suggest that the physiological characteristics of plant should take into accounts for restoration and choose salt-tolerable tree species. Moreover, the soil organic carbon content is very low in study site, and the suggestion is to apply a large number of agricultural wastes with higher fiber many times per year in study area. The purpose of this application is to improve the soil physical characteristics first and to improve the soil fertility further for supplying more nutrients for ground covers.

並列關鍵字

Nanao area ； coastal windbreak ； soil characteristics ； spatial variability