文献类型：期刊文献

中文题名：氮添加对三峡库区马尾松人工林土壤团聚体有机氮组分和氮矿化的影响

英文题名：Effects of nitrogen addition on acidolyzable organic nitrogen components and nitrogen mineralization in aggregates of Pinus massoniana plantations in the Three Gorges Reservoir area,China

作者：陈天[1] 程瑞梅[1,2] 沈雅飞[1,2] 肖文发[1,2] 王丽君[1] 孙鹏飞[1] 张萌[1] 李璟[1]

第一作者：陈天

机构：[1]中国林业科学研究院森林生态环境与自然保护研究所,国家林业和草原局森林生态环境重点实验室,北京100091;[2]南京林业大学,南方现代林业协同创新中心,南京210037

年份：2023

卷号：34

期号：10

起止页码：2601-2609

中文期刊名：应用生态学报

外文期刊名：Chinese Journal of Applied Ecology

收录：CSTPCD;;Scopus;北大核心:【北大核心2020】；CSCD:【CSCD2023_2024】；PubMed;

基金：中国林业科学研究院基本科研业务费专项(CAFYBB2021ZE003)资助。

语种：中文

中文关键词：氮添加;团聚体;矿化;有机氮

外文关键词：nitrogen addition;aggregate;mineralization;organic nitrogen

分类号：S15

摘要：以三峡库区马尾松人工林为对象,将土壤筛分为大团聚体(2000~8000μm)、粗砂粒(1000~2000μm)、小团聚体(250~1000μm)和微团聚体(<250μm)4个粒径,研究低、中、高氮添加处理(氮添加量分别为30、60、90 kg N·hm^(-2)·a^(-1))下土壤酸解性有机氮组分和净氮矿化的变化。结果表明:不同处理下,团聚体净硝化速率为0.30~3.42 mg N·kg^(-1),占净氮矿化的80%以上。与对照相比,不同处理4个粒径的总氮含量分别提高24.1%~45.5%、6.4%~34.3%、7.9%~42.4%,净氮矿化速率分别提高1.3~7.2、1.4~6.6、1.8~12.9倍,而速效磷含量分别降低9.3%~36.9%、12.2%~56.7%、19.2%~61.9%。可酸解性有机氮组分、有机质含量以及净氨化、净硝化和净氮矿化速率均随着团聚体粒径的减小而增加,但速效磷含量变化呈相反的趋势。酸解性有机氮组分含量大小为:酸解氨基酸态氮>酸解铵态氮>酸解未知态氮>酸解氨基糖态氮。总氮是提高酸解性有机氮组分含量的主导因子。多元逐步回归显示,酸解氨基酸态氮和酸解氨基糖态氮含量影响了净氨化速率;酸解氨基糖态氮、酸解氨基酸态氮和酸解铵态氮含量共同影响了净硝化、净氮矿化速率以及净氮矿化累积量。综上,团聚体的物理结构影响了土壤氮矿化,氮添加提高了土壤生物可利用性及易矿化态酸解性有机氮的含量,但大量氮添加导致土壤有机质和速效磷含量下降。
We sieved soils from a Pinus massoniana plantation in the Three Gorges Reservoir area into four aggregate sizes,including aggregates of 2000-8000μm(large macroaggregates),1000-2000μm(coarse aggregates),250-1000μm(small macroaggregates),and<250μm(microaggregates).We analyzed the differences in the acidolyzable organic N components and net N mineralization of the aggregates under different N addition levels(30,60,and 90 kg N·hm^(-2)·a^(-1),representing by N30,N60 and N90,respectively).The results showed that net nitrification rate of the aggregates ranged from 0.30-3.42 mg N·kg^(-1)and accounted for more than 80%of net nitrogen mineralization.Compared with the control,addition of 30,60,and 90 kg N·hm^(-2)·a^(-1)increased total N by 24.1%-45.5%,6.4%-34.3%,and 7.9%-42.4%in the large aggregates,coarse aggregate,small macroaggregates,and microaggregates,increased net N mineralization rate by 1.3-7.2,1.4-6.6,and 1.8-12.9 times,but decreased the contents of available phosphorus by 9.3%-36.9%,12.2%-56.7%,and 19.2%-61.9%,respectively.The contents of total acidolyzable N,soil organic matter,and rates of net ammonification,net nitrification,and net N mineralization increased as the aggregate size decreased,while available phosphorus contents showed an opposite trend.The levels of acid-hydrolyzable N components were ranked as acidolyzable amino acid N>acidolyzable ammonia N>acidolyzable unknown N>acidolyzable amino sugar N.Total N was the dominant contributor to the increases in acid-hydrolyzable N components.Results of stepwise multiple regression analyses showed that acidoly-zable amino acid N and acidolyzable amino sugar N were predictors of net ammonification rate.Acidolyzable amino sugar N,acidolyzable amino acid N,and acidolyzable ammonia N were predictors of net nitrification,net nitrogen mineralization rate,and net nitrogen mineralization accumulation.The physical structure of aggregates was associa-ted with soil net N mineralization.Addition of N increased the contents and bioavailability of acidolyzable organic N,a large amount of which contributed to soil organic matter levels and the decrease in available phosphorus.