Nutrient losses from teak stump harvesting
1992
Boonlert Srisuksai (Forest Industry Organization, Bangkok (Thailand))
Study was conducted to observe soil nutrient losses after harvesting of teak seedlings for stump preparation. Eight-month-old seedlings from the FIO nursery centre at Mae Moh, Lampang, were used in this study. Four sample plots of size 1*1 m were selected at random, the seedlings were lifted and their size class distribution were graded. The lifted seedlings were then partitioned in to root, stump (tap-root), stem and leave parts for their biomass assessment and nutrient (N, P, K, Ca and Mg) analysis. The average height and diameter (at the root collar level) of the seedlings were 34.6 and 0.6 cm, respectively. The seedling density was 143 seedlings/square m (i.e. 27.4 % of seed sown). The average number of usable seedlings (optimum size for out planting) was 28 seedlings/aquare m. (i.e. 19.8 % of seed sown). The nutrient analysis showed that the total amount of N, P, K, Ca and Mg content in a teak seedling were 3.56, 0.48, 5.38, 1.84 and 0.85 % (of total dry weight), respectively. Conversely, the total amount of N, P, K, Ca and Mg losses from the nursery centre were 16.38, 1.92, 16.96, 6.91 and 3.01 kg/rai (6.25 rai=1 ha).
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