海岸防風林破壞跡地林下栽植更新試驗

Regeneration of Deforested Sites of Coastal Windbreaks by Underplanting

甘偉航(Wei-Hong Kan) ； 胡大維(Ta-Wei Hu)

《林業試驗所研究報告季刊》 2卷1期 (1987/03) Pp. 1-15

https://doi.org/10.7075/BTFRI.198703.0001

摘要

在海岸防風林破敗林分之空隙，以修枝及伐除障礙木法，於林下植樹進行更新，試區內分單一樹種及多樹種混植，試驗項目14項，結果：苗木帶土定植成活率高達80%以上（九重吹99.5%最高），只有1、2種較低（黃檀73.8%最少）。生長量：造林滿3年之總生長量，各樹種以巨型銀合歡（平均高7.5m基徑6.1cm），黃槿（高4.5m徑7.8cm）較好；樹種混植區，各樹種生長量大小參差，樹種配合在林分組成上之功能尚不明顯；各年淨生長，第3年樹高生長多呈減降，巨型銀合歡、黃槿減降最明顯；肥大生長多呈增加，其減降者趨勢緩和；淨生長樹種間差異極顯著，適應性差者，生長量微少或不見生長，枯死甚多。光度：生長期各試區之相對光度在50%以上者佔85%，季風期，由於枝葉枯落，50%以上光度的比數高達97%。枝梢枯損，72年度耳莢相思（平均枯枝長約50.0cm）及豆類植物混植者（平均是42.0cm）枯梢量最大，海岸樹種混植區（平均枯梢是8.0cm）則較小。風速與耳莢相思之枯枝長度呈極顯著之直線回歸關係。各試區內只有巨型銀合歡林下有稚苗發生，定植滿2年試區內自生競存苗木多達389株，滿3年區內小苗最多1,363株，混植區較純林區自生苗少。

關鍵字

防風林 ； 更新

並列摘要

This experiment was conducted during the 1981 planting season at coastal windbreak of Hou-Lun, Mao-Li, with 12 tree species each as treatment and two additional planting conditions. (Eight leguminous tree specks and eight native coastal species mixed in a plot, respectively). They were made 14 treatments and aranged randomly with three replications. That the trees were planted in deforested sites by means of underplanting. After 3-year growth of various trees, highly significant differences are found amony treatments in total growth, having a range of 749 to 1.43m. for height growth, and 6.06 to 1.76cm. in diameter. Leucaena leucocephala was the leading. The growth Casuarina equisetifolia, Celtis formosana, and Acacia auriculaeformis also grew well; the growth of Eucalyptus microtheca was poor. (Tab. 2.). Total growth of the 2 accessions M(subscript L)* (Eight leguminous tree species plot) and Mc* (Eight coast tree species plot) also have highly significant differences; in the former (M(subscript L)),* Leucoena leucocephala, Albizia lebbek, Calliandra callothyrsus and Acacia auriculaeformis are better. Dalbergia sisso and Acacia cyanophylla, worse. (Tab. 3.); in the latter (Mc),* Hibiscus tiliaceus is the best with height growth of 4.5m. and diameter, 7.76cm. Drypetes lttloralis and Palaquim formosanum are poor, having a growth ranging from 0.43-0.63m. in height and 0.66-0.93cm. in diameter (Tab. 4.). Annual current height growth showed decrease in the third year, that the growth of Leucaena leucocephala and Hibiscus tiliaceus dropped abruptly that the current height growth was 3.48m. (2ed year) and 1.14m. (3rd year) for the former, and 2.08m. (2ed year) and 0.60m. (3rd year), the latter; the increment of annual diameter growth depended upon the tree species; in the third year, the growth of some species increased and some other dropped, even so, the trend of dropping was gently. Relative light intensity of over fifty percent had 85% in the experimental area. The relationship between windvelocity and winddamaged length of branch of Acacia auriculaformis, was significant in linear regression test (Fig. 1). That the branch was damaged severely in the area with strong wind. Natural seedlings of Leucaena leucocephala were found in the experimental area. That 152-389 seedlings presented in a plot in the second year, 322-1,263 seedling, in third year; height of seedlings under 5cm. had ninety percent for the former, under 50cm., eighty eight percent, for the latter.
In view of the fact that the species of Hibiscus tiliaceus, Leucaena leucocephala, Casuarina sp., Celtis formosana, Acacia auriculaeformis and Albizia lebbek could be an outstanding candidates for providing coast windbreak on regeneration needs.