氮添加及凋落物管理对樟子松人工林土壤理化性质的影响  

Effect of nitrogen addition and litter manipulation on soil physicochemical properties of a Pinus sylvestris var. mongolica plantation

作　　者：赵欣然[1,2] 赵琼[1] 王巍巍[1] 杨丹[3] 郑琳琳[1,2] 艾桂艳[1] 曾德慧[1] ZHAO Xin-ran ZHAO Qiong WANG Wei- wei YANG Dana ZHENG Lin-lin AI Gui-yan ZENG De-hui(IDaqinggou Ecological Station, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China University of Chinese Academy of Sciences, Beijing 100049, China College of Biological and Environmental Engineering, Guiyang University, Guiyang 550025, China）.)

机构地区：[1]中国科学院沈阳应用生态研究所大青沟沙地实验站,沈阳110016 [2]中国科学院大学,北京100049 [3]贵阳学院生物与环境工程学院,贵阳550025

出　　处：《生态学杂志》2016年第10期2699-2706,共8页Chinese Journal of Ecology

基　　金：国家自然科学基金项目(41373087);贵州省科学技术基金项目(黔科合J字[2013]2299号)资助

摘　　要：氮沉降和凋落物量的改变是全球变化影响森林生态系统的重要途径,然而二者的交互作用对土壤生态过程的影响仍知之甚少。本文研究氮添加(对照和添加10 gN·m^(-2)·a^(-1))和地表凋落物管理(对照、移除和加倍)对科尔沁沙地樟子松人工林干季(5月)和湿季(8月)土壤有效氮、基础呼吸和有效磷等的影响。结果表明:凋落物管理对土壤的影响在对照和氮添加样地中差异较大;在对照样地中,凋落物移除和加倍都显著提高了8月土壤呼吸,对有效磷和氮含量基本上无显著影响;在氮添加样地,凋落物移除与加倍均未影响土壤呼吸和有效磷含量,但显著降低有效氮含量;氮添加和凋落量变化的影响在湿季大于干季;单一的氮添加显著降低了8月的土壤有效磷含量和土壤呼吸,而凋落物量加倍减缓了氮沉降对土壤呼吸的抑制和磷限制性的加剧。Nitrogen （N） deposition and litterfall variation are main pathways by which global change impacts forests, but how they interact to change belowground processes is poorly known. To explore these interactions, we conducted a field manipulative experiment under nitrogen addi- tion （control and N addition as 10 g N · m^-2 · a^-1） and litter manipulation （ambient litterfall, litter removal and litter doubling） in a Pinus sylvestris var. mongolica plantation in Keerqin Sandy Land. We measured soil properties such as available N and P concentrations and basal respiration rate in dry and wet seasons （May and August） 3 years after manipulation. The results showed that impacts of litter manipulation on soil variables differed greatly in the control and N addition plots. In the control plots, both litter removal and doubling greatly elevated soil basal respiration, while generally did not change available P and N concentrations. In N addition plots, both litter removal and doubling did not change basal respiration and available P concentration, but greatly decreased available N concentration. Impacts of N addition and litter manipulation were more ob- vious in wet season than in dry season. Nitrogen addition alone significantly reduced basal respi- ration and available P concentration in August, while litter doubling effectively lessened the de- pression of respiration and enhanced P limitation caused by N addition.

关 键 词：氮添加 凋落物移除 凋落物加倍 有效氮 呼吸速率 有效磷 

分 类 号：S714[农业科学—林学]