Contribution of Harvest Residues to Nutrient Cycling in a Tropical Acacia mangium Willd. Plantation

Forests

卷:9

Daniel Mendham¹  HoangVan Thanh²  VoDai Hai²  NguyenVan Thinh²  TranLam Dong²  Caroline Mohammed³  Alieta Eyles³  David Ratkowsky³  Nguyen Van Bich³  KatherineJ. Evans³ 

[1] CSIRO Land and Water, Private Bag 12, Hobart, Tasmania 7001, Australia;

[2] Silviculture Research Institute (SRI), Vietnamese Academy of Forest Sciences (VAFS), 46 Duc Thang, Bac Tu Liem, Hanoi 11910, Vietnam;

[3] Tasmanian Institute of Agriculture (TIA), University of Tasmania, Private Bag 98, Hobart, Tasmania 7001, Australia;

关键词: nutrient loss;    mass loss;    nutrient release;    nutrient dynamics;    decay constant;    residue half-life;    nutrient cycling;    tropical plantation;   

DOI  :  10.3390/f9090577

来源: DOAJ

【 摘 要 】

Harvest residues can play a crucial role in conserving nutrients for recycling in forests, but little is known about the rates of decomposition and nutrient release from these residues following logging in tropical acacia plantations. In this study, we examined the biomass and nutrient content of harvest residue components (bark, leaves, and branches) using the litterbag technique for a 1.5-year-period following harvest of a seven-year-old Acacia mangium plantation in Northern Vietnam. At harvest, the total dry biomass of harvest residues was 18 t ha−1 comprising bark (8.9 t ha−1), branches (6.6 t ha−1), and leaves (2.5 t ha−1). The retained bark on site conserved 51% N, 29% P, 32% K, 64% Ca, and 24% Mg content from harvest residues for recycling. Decomposition rate of the leaves was the most rapid (k = 1.47 year−1; t0.5 = 0.47 year), then branches (k = 0.54 year−1; t0.5 = 1.29 year), and bark (k = 0.22 year−1; t0.5 = 3.09 year). During decomposition, the loss of nutrients from harvest residues was K ≈ Ca > N > P> Mg. Decomposition of harvest residues and the associated rate of nutrient release can potentially supply a significant amount of nutrients required for stand development in the next rotation.

【 授权许可】

Unknown