秋季施肥对毛白杨苗木质量、造林效果和养分回流的影响  

Effects of Autum Fertilization on Quality,Field Performance and Nutrient Resorption of Populus tomentosa Seedling

作　　者：王苗苗 刘勇[1] 李国雷[1,2] 彭玉信 刘春和 赵建松 王书红 蕫彪 王长伟 赵蕊蕊 Wang Miaomiao;Liu Yong;Li Guolei;Peng Yuxin;Liu Chunhe;Zhao Jiansong;Wang Shuhong;Dong Biao;Wang Changwei;Zhao Ruirui(Key Laboratory for Silviculture and Conservation of Ministry of Education, Beijing Forestry University,Beijing 100083;Beijing Laboratory of Urban and Rural Ecological Environment,Beijing 100083;Beijing Huangfa Nursery,Beijing 102601)

机构地区：[1]北京林业大学省部共建森林培育与保护教育部重点实验室,北京100083 [2]城乡生态环境北京实验室,北京100083 [3]北京市黄垡苗圃,北京102601

出　　处：《林业科学》2021年第7期51-60,共10页Scientia Silvae Sinicae

基　　金：国家重点研发专项“白杨工业资源材高效培育技术研究”(2016YFD0600403)。

摘　　要：【目的】探究秋季施肥对苗木质量、养分贮存和造林效果的影响,明确苗木生长与养分回流的内在联系,确定最佳施肥水平,为苗木培育精准施肥提供参考。【方法】以三倍体毛白杨组培苗“北林雄株1号”为试验材料,顶芽形成后进行秋季施肥,每周1次,连续6周平均施入(9月2日—10月7日)。采用单因素完全随机区组设计,设置3个秋季施肥水平和1个对照,每株施肥0、5、10和20 g(水溶肥花多多1号:20%N+20%P2O5+20%K2O+TE),分析秋季施肥对苗圃阶段苗木生长、养分贮存和非结构性碳水化合物水平以及造林后苗木成活、生长和养分回流等的影响。【结果】1)秋季施肥对苗圃阶段苗木生长的影响较小,但可显著促进苗木尤其是根系氮贮存和非结构性碳积累,茎、根氮浓度分别提高2.4%~12.0%和17.4%~48.1%,根淀粉浓度提高17.9%~34.5%;秋季同时施用氮、磷、钾肥,主要提高氮贮存而不影响磷、钾贮存,表现出氮元素利用偏好性;2)翌年造林后,苗高、地径和茎体积生长量在施肥量每株10 g时达到最大(分别比对照提高40.0%、80.4%和85.3%),苗圃施肥效果得以充分体现;苗圃施肥量每株20 g的苗木造林后生长受抑,成活率最低(63.3%);3)造林后苗木(施肥量每株10 g时)生长量的提高可提升氮回流效率(71%),降低落叶氮淋失(56.4%);4)回流效率的变化并非受单一元素控制,而与叶片中多种元素的浓度变化相关;氮回流效率与落叶氮、落叶钾浓度呈负相关,与绿叶磷、落叶磷浓度呈正相关;磷回流效率与绿叶氮浓度呈正相关。【结论】苗木氮贮存量、非结构性碳积累量、翌年造林成活率和生长量是评价秋季施肥效果的主要指标,苗圃合理秋季施肥能够提高苗木氮贮存和非结构性碳积累,进而提高苗木翌年造林成活率和生长表现;造林后,苗木生长量的提高可提升叶片氮回流效率,降低落叶氮淋失。秋季施肥是一种理想�【Objective】In the present study,we explored optimal fall fertilization regime by investigating seedling quality and field performance of Populus tomentosa in order to provide a theoretical basis for nursery accurate fertilization management.Furthermore,we examined the inner-mechanism of growth and nutrient resorption in field.【Method】In this study,triploid P.tomentosa was used as experimental materials.Fertilization was carried out in fall after the formation of terminal buds,once a week for consecutive six weeks(from September 2 to October 7).A completely randomized block design with one factor was used to set four fertilization levels:0,5,10,20 g fertilizer per seedling totally(a water-soluble commercial fertilizer:20%N+20%P2O5+20%K2O+TE).Seedling height,diameter and stem biomass(or stem volume)were measured at the beginning and end of each growing season.We also determined nutrient concentration and non-structural carbohydrate(NSC)levels in stems and roots in nursery,as well as nutrient concentration in green and senesced leaves in field.【Result】1)In nursery,fall fertilization had little effect on seedling growth,but significantly increased N and NSC accumulation,especially in roots.The N concentration in stems and roots increased by 2.4%-12.0%,17.4%-48.1%,respectively,and the root starch concentration increased by 17.9%-34.5%.Fall fertilization with N,P and K was mainly enhanced N storage but no significant effect on P or K storage,indicating the preference for N utilization.2)In field,the growth of height,diameter and stem volume reached the maximum when the fertilizer amount was 10 g per seedling(increased by 40.0%,80.4%and 85.3%respectively compared with the control),fully exhibiting the effects of fall fertilization in the nursery.When fertilization rate increased to 20 g per seedling,the seedling growth was inhibited and the survival rate the minimum of(63.3%)after afforestation.The result demonstrated that it is important to optimize fall fertilization rate.3)Furthermore,the enhance of growt

关 键 词：秋季施肥 养分贮存 造林效果 生长 养分回流 

分 类 号：S718.43[农业科学—林学]