Aboveground Net Primary Production at Acacia mangium Plantation in Northern Vietnam
Nguyen Toan Thang *
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
Vu Tien Lam
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
Dang Van Thuyet
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
Phung Dinh Trung
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
Pham Dinh Sam
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
Tran Hoang Quy
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
Nguyen Thi Thu Phuong
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
Ly Thi Thanh Huyen
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
Nguyen Huu Thinh
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
Nguyen Van Tuan
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
Dao Trung Duc
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
Dang Thi Hai Ha
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
Duong Quang Trung
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
Ho Trung Luong
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
Nguyen Thi Hoai Anh
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
Mai Thi Linh
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
Tran Van Do
Silviculture Research Institute, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam.
*Author to whom correspondence should be addressed.
Abstract
Net primary production (NPP) is an important index for understanding carbon cycling in forest ecosystems. In this study, aboveground NPP at Acacia mangium plantation was estimated basing on allometry for aboveground biomass increment (ΔM) and litter trap technique for litterfall (Lf). The experiment was conducted in two plots of 300 m2 each (15 × 20 m), established at a 21-month old plantation. Data were collected five times of 3-month intervals in a total duration of 357 days. The results indicated that Lf and ΔM were seasonal-dependent. Litterfall was highest (4.06 g m-1 day-1) during Sep-Jan (late rainy season, early winter) and lowest (1.10 g m-1 day-1) during Mar-Jun (early rainy season, early summer). While, ΔM was highest (13.51 g m-1 day-1) during Jun-Sep (rainy season, summer) and lowest (3.10 g m-1 day-1) during Jan-Mar (dry season, winter). Total Lf in a duration of 357 days was 9.69 tons ha-1 and ΔM was 27.71 tons ha-1, leading to total aboveground NPP of the present study plantation of 37.40 tons ha-1. It is concluded that aboveground NPP of acacia plantation was much higher than other forests of different types and ages around the world. Such difference indicates the importance of acacia plantation in soil nutrient cycling through litterfall decomposition and carbon sequestration through aboveground biomass increment.
Keywords: Aboveground biomass, acacia plantation, carbon cycle, litterfall, nutrient return