[Effects of Fargesia denudata density on its litterfall production, nutrient return, and nutrient use efficiency].
A two-year study on the effects of three densities (D1, 80 +/- 5 stems x m(-2); D2, 140 +/- 8 stems x m(-2); and D3, 220 +/- 11 stems x m(-2)) of Fargesia denudate in a F. denudata--Picea purpurea natural forest on the F. denudate litterfall production, nutrient return, and nutrient use efficiency showed that at the densities of D1, D2 and D3, the annual litterfall production was 793.2, 1135.7 and 1458.5 kg x hm(-2), carbon return was 370.7, 516.2 and 671.5 kg x hm(-2), and the total return of N, P, K, Ca and Mg was 16.3, 22.9 and 29.3 kg x hm(-2), respectively. Ca had the highest return (45%-48% of the total), followed by N (24%-29%), and the lowest were P and Mg (3%-5%), with the sequence of Ca > N > K > Mg and P. The peaks of litterfall production and nutrients return at the three densities were appeared in October (by the end of F. denudate growth season), and another peak at D3 was observed in August. There were no significant differences in the re-allocation of N and K in F. denudate leaves at the three densities, but the P re-allocation and the Ca and Mg accumulation increased with increasing density. The litterfall P use efficiency was the highest and increased with increasing density, implying that P could be a limiting factor for the growth and regeneration of F. denudate.
Qi
Ze-Min
ZM
Department of Chemistry and Biology, Neijiang Normal University, Neijiang 641112, China. zmin918@sina.com.cn
Wang
Kai-Yun
KY
D018533:Biomass; D002244:Carbon / Q000032:analysis; D003247:Conservation of Natural Resources; D017753:Ecosystem; D009584:Nitrogen / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D028222:Picea / Q000254:growth & development / Q000378:metabolism; D018515:Plant Leaves / Q000254:growth & development* / Q000378:metabolism; D031787:Sasa / Q000254:growth & development* / Q000378:metabolism; D012987:Soil / Q000032:analysis
D012987:Soil; D010758:Phosphorus; D002244:Carbon; D009584:Nitrogen