沿海沙地3种竹林土壤易氧化有机碳研究

分析福建省东山赤山国有防护林场沿海沙地绿竹、麻竹、大头典竹3种竹林不同土层、不同季节土壤易氧化有机碳(ROC)含量变化特征,以及土壤ROC与总有机碳(SOC)、全氮、全磷、全硫、pH值、土壤温度等指标的相关性,为探寻沿海沙地竹林碳循环规律提供基础数据。研究表明:沿海沙地3种竹林土壤ROC含量季节变化特征明显,不同季节间含量差异达到极显著水平,3种竹林季节变化规律基本一致,夏、春、秋季较高,冬季最低;大头典竹林土壤ROC含量最高,绿竹林高于麻竹林,且差异性极显著;土壤ROC含量随着深度的增加而减小,不同土层之间差异极显著;土壤ROC与SOC、全氮呈显著正相关,与pH值呈极显著负相关,与全磷、全硫、土壤温度等指标相关性不显著。沿海沙地3种竹林土壤ROC的季节和空间分布特征有一定差异性,土壤SOC、pH值、全氮是ROC在不同竹林间产生差异的主要原因。

Study on Soileasily Oxidized Organic Carbon of Different Bamboo Forests on Coastal Sandy Land

In order to provide basic data for exploring the law of bamboo forest carbon cycle in coastal sandy sites, this paper was focused on analyzing the varied characteristics of soil easily oxidized organic carbon (ROC) content, as well as the correlation between soil ROC and some indexes including total organic carbon (SOC), total nitrogen (N), total phosphorus (P), total sulfur (S), pH value and soil temperature under different soil layers and seasons within three kinds of bamboo forests, such as Dendrocalamopsis oldhami, Dendrocalamus latiflorus and Dendrocalamopsis beecheyana var. pubescens on the Fujian Chishan state-owned forest farm. The soil ROC content of three bamboo forests in coastal sandy sites changed obviously along with the seasons, the content differences in different seasons reached an extremely significant level (P<0. 01). Seasonal dynamic that the soil ROC content was higher in summer, spring, autumn and the lowest in winter, which was largely consistent among three bamboo forests. The soil ROC content of Dendrocalamopsis beecheyana var. pubescens forest was the highest, followed by that of Dendrocalamopsis oldhami forest and Dendrocalamus latiflorus forest, with an extremely significant difference (P< 0. 01). The soil ROC content decreased with the increase of depth, and the difference among different soil layers was extremely significant (P<0. 01). The content of soil ROC had a significant positive correlation with those of SOC and total N, a negative correlation with pH value, and no significant correlation with total P, total S and soil temperature. The spatial distribution characteristics of soil ROC in three kinds of bamboo forests on coastal sandy sites are different along with different seasons. The main reasons for the difference between different bamboo forests are soil SOC, pH value and total N.