土壤氮浓度对油松天然林新生枝叶碳氮磷化学计量及其内稳态的影响  

Effects of Soil Nitrogen Concentration on Carbon,Nitrogen and Phosphorus Stoichiometry and Homeostasis of New Branches and Leaves in Natural Pinus tabulaeformis Forest

作　　者：闫鑫泽 段嵩岚 郑蓉蓉 刘立宝 岳国强 张芸香[1,2] 刘晓娥 郭晋平 YAN Xinze;DUAN Songlan;ZHENG Rongrong;LIU Libao;YUE Guoqiang;ZHANG Yunxiang;LIU Xiaoe;GUO Jinping(College of Forestry,Shanxi Agricultural University,Taigu,Shanxi 030600;Shanxi Key Laboratory of Cultivation and R&d of Functional Oil Tree Species in North China,Taigu,Shanxi 030600;Xiaowen Mountain Forest Farm,Guandi Mountain National Forest Management Bureau,Jiaocheng,Shanxi 030500)

机构地区：[1]山西农业大学林学院,山西太谷030600 [2]北方功能油料树种培育与研发山西重点实验室,山西太谷030600 [3]山西省关帝山国有林管理局孝文山林场,山西交城030500

出　　处：《水土保持学报》2023年第2期294-300,309,共8页Journal of Soil and Water Conservation

基　　金：山西农业大学学术恢复科研专项(2020XSHF34);山西省林业科技创新项目“典型林区油松林近自然经营技术研究”(2018LYCX32)。

摘　　要：为了解油松(Pinus tabuliformis)天然林新生枝叶碳(C)、氮(N)、磷(P)化学计量特征对土壤氮浓度改变的响应及其林龄差异,揭示不同龄级油松新生枝叶N、P元素内稳态对短期氮添加的响应。以关帝山林区孝文山林场Ⅴ~Ⅶ龄级油松天然次生林为研究对象,采用野外原位氮添加试验的方法,设置对照(N 0,0)、低氮(N 1,5 g/m 2)、中氮(N 2,10 g/m 2)和高氮(N 3,15 g/m 2)4个施氮水平,形成不同土壤N浓度梯度,分析不同N浓度新生枝和叶C、N、P计量指标和内稳态指数。油松枝叶C、N、P含量随土壤氮浓度的增加而显著增加,C/N和C/P减小;油松枝叶C含量、C/N和C/P随龄级增加而增加,N、P含量随龄级增加而减少;根据针叶N/P,该地区油松生长主要受N限制;新生枝和叶N、P含量及N/P与土壤指标的关系均能很好被内稳态模型模拟(p<0.1),其中新生枝P含量对土壤供氮水平变化敏感,而其他指标较稳定,新生叶的内稳态高于新生枝。该地区油松通过调节枝叶氮磷吸收与利用策略保持新生枝叶内稳态以适应土壤氮浓度增加及由此带来的变化。To understand the response of carbon(C),nitrogen(N)and phosphorus(P)stoichiometric characteristics of the new branches and leaves in natural Pinus tabulaeformis forest to changes in soil nitrogen concentration and differentstand age,and to reveal the response of N and P homeostasis in the new branches and leaves of Pinus tabuliformis at different stand ages to short-term nitrogen addition,taking the natural secondary forest of Pinus tabulaeformis with age V~VII of Xiaowen mountain forest farm in Guandi mountain forest area as the research object,the field in-situ comparative test with different nitrogen application rates was used to set four nitrogen application levels:control(N0,0),low nitrogen(N1,5 g/m 2),medium nitrogen(N2,10 g/m 2)and high nitrogen(N3,15 g/m 2),and the contents of C,N and P in new branches and leaves and their stoichiometric ratios and homeostasis indexes were analyzed under different soil nitrogen concentrations.The contents of C,N and P in the branches and leaves of Pinus tabulaeformis increased significantly with the increase of soil nitrogen concentration,while the contents of C/N and C/P decreased;the contents of C,C/N and C/P in the branches and leaves of Pinus tabulaeformis increased with the increase of forest age,while the contents of N and P decreased with the increase of forest age;according to leaf N/P,the growth of Pinus tabulaeformis in this area was mainly limited by N;the relationship between N,P and N/P in new shoots and leaves with corresponding soil parameters could be adequately simulated by an internal homeostasis model(p<0.1),the content of P in new shoots was sensitive to the change of soil nitrogen supply level,while the other indexes were stable,and the homeostasis of new leaves was higher than that of new shoots.The Pinus tabulaeformis maintained the internal stability of new branches and leaves by adjusting nitrogen and phosphorus uptake and utilization strategies to adapt to the increase of soil nitrogen concentration and the resulting changes.

关 键 词：土壤氮浓度 生态化学计量 内稳态 新生枝和叶 油松天然林 关帝山林区 

分 类 号：S791.254[农业科学—林木遗传育种]