沿海沙地吊丝竹林凋落物及养分动态研究

对沿海沙地吊丝竹林的凋落物及养分月动态特征进行连续观测分析,研究结果表明:竹林凋落物量月动态呈现双峰型模式,2个峰值分别出现在2004年10月和2005年4月,这2个月凋落物量占全年总量的26.90%;2005年1月和7月凋落物量较少,只占全年总量的8.92%。各营养元素在凋落物中组分平均值大小排列顺序为:N>K>P>Mg>Ca。凋落物N、P、K、Mg归还量月动态全年呈现出2个峰值期,分别出现在2004年10~11月和2005年4~5月;Ca只有单峰值期,出现在2004年10~11月。凋落物各营养元素归还量最大是N,年归还总量为58.32 kg.hm-2,最小是Ca,只有0.61 kg.hm-2。N、P、K、Mg、Ca在峰值期养分归还量分别占全年比例的48.44%、47.12%、50.48%、53.49%和36.30%。沿海沙地吊丝竹林凋落物年养分归还量为97.54 kg.hm-2。

Study on the litter and nutrient dynamics of Dendrocalamus minor plantation in the coastal sandy site

Based on continuous observation of the litter and nutrient monthly dynamic of Dendrocalamus minor plantation in coastal sandy site,the results indicated that the bamboo plantation litter monthly dynamic presented a double-peak form in the October of 2004 and April of 2005 respectively,and the amount of the two monthly litter occupied 26.90% of total in whole year,less in the January and May of 2005,of which only 8.92%.The average value of components of nutrient elements in the litter were N>K>P>Mg>Ca.The N,P,K and Mg of the litter monthly return dynamic in whole year presented two peak periods form October to November of 2004 and April to May of 2005 respectively,but Ca only had single peak period from October to November of 2004.The biggest of the litter monthly return dynamic was N,whose all-year return amount was 58.32 kg·hm-2,the least was Ca with 0.61 kg·hm-2.The nutrient return amount of N,P,K,Mg,Ca in the peak period occupied 48.44%,47.12%,50.48%,53.49% and 36.30% of the whole year,respectively.The nutrient annual return amount of D.minor plantation in the coastal sandy site was 97.54 kg·hm-2.