物候变化对落叶松人工林降雨分配过程中钾和钠离子迁移的影响  

Effects of phenoseason on transfer of potassium and sodium ions in the process of rainfall redistribution in larch (Larix gmelinii) plantations

作　　者：盛后财[1] 姚月锋[2] 蔡体久[1] 郭娜[3] 琚存勇[1] SHENG Houcai;YAO Yuefeng;CAI Tijiu;GUO Na;JU Cunyong(Key Laboratory of Sustainable Forest Ecosystem Management,Ministry of Education,College of Forestry,Northeast Forestry University,Harbin 150040,China;Guangxi Institute of Botany,Chinese Academy of Sciences,Guangxi Zhuang Autonomous Region,Guilin 541006,China;Department of Food and Environmental Engineering,East University of Heilongjiang,Harbin 150066,China)

机构地区：[1]东北林业大学林学院,森林生态系统可持续经营教育部重点实验室,黑龙江哈尔滨150040 [2]广西壮族自治区中国科学院广西植物研究所,广西桂林541006 [3]黑龙江东方学院食品与环境工程学部,黑龙江哈尔滨150066

出　　处：《南京林业大学学报（自然科学版）》2021年第6期143-150,共8页Journal of Nanjing Forestry University：Natural Sciences Edition

基　　金：黑龙江省自然科学基金项目(LH2020C032);中央高校青年教师创新项目(2572018BA10)。

摘　　要：【目的】森林冠层导致的穿透雨和树干茎流中离子通量的季节变化,能够影响森林生态系统生物地球化学循环,对物候变化明显的温带落叶林的影响更为突出。探究不同物候期(展叶期、盛叶期和落叶期)森林水化学过程,深入了解森林生态系统养分元素循环过程,为温带落叶林生物地球化学循环提供基础数据。【方法】以东北林业大学城市林业示范基地内落叶松人工林为研究对象,在观测样地的中心位置十字交叉布设13个直径20 cm自制雨量筒,并选择5株落叶松安装树干茎流收集器,同时在林外布置1台翻斗式雨量计和3个自制雨量筒。在前期观察期(2015年5月1日—10月31日)每次降雨事件后,对林外降雨、穿透雨和树干茎流进行观测、取样,水样过滤酸化处理后用火焰原子吸收分光光度计测定Na^(+)和K^(+)质量浓度,探索冠层的物候变化对降雨分配过程中Na^(+)和K^(+)的质量浓度和净输入量的影响。【结果】整个观测期间,林外降雨中Na^(+)、K^(+)的质量浓度分别为0.45和1.89 mg/L,穿透雨中分别为0.44和2.48 mg/L,树干茎流中分别为1.98和18.63 mg/L;大气降雨中Na^(+)质量浓度在落叶期最高,盛叶期最低,K^(+)质量浓度则在落叶期最高,展叶期最低;各时期穿透雨中Na^(+)和K^(+)质量浓度大小均为落叶期>盛叶期>展叶期;树干茎流中Na^(+)和K^(+)质量浓度大小均为展叶期>盛叶期>落叶期;生长季内林冠对降雨中Na^(+)的截留量为0.252 kg/hm^(2),其中展叶期和落叶期的截留量分别为0.143和0.193 kg/hm^(2),截留率分别为30.63%和48.22%,盛叶期则表现为淋溶,淋溶量为0.083 kg/hm^(2);生长季内降雨对林冠中K^(+)的淋溶量为0.903 kg/hm^(2),其中展叶期和盛叶期的淋溶量分别为0.999和0.157 kg/hm^(2),落叶期则为截留,截留量为0.254 kg/hm^(2),截留率为20.25%。【结论】大气降雨经过森林冠层后离子质量浓度发生明显改变,且不同物候期、【Objective】 The seasonal variations in ionic fluxes in throughfall and stemflow resulting from washoff and leaching by forest canopy indicate significant processes affecting the biogeochemical cycling of forested ecosystems, particularly in temperate deciduous forests with distinct phenological seasons. Previous studies on the water chemistry of forest ecosystems have been focused on the growing season as a time scale to discuss the changes in element fluxes, but ignored the influence of leaf phenology changes on water chemistry during the growing season. Therefore, our objective is to determine the impacts of phenological changes on the water chemistry of forest ecosystems and to better understand the nutrient element cycle process of temperate deciduous forest ecosystems.【Method】In this study, we selected a Larix gmelinii plantation in the Northeast Forestry University Urban Forestry Demonstration Base as the research subject. Thirteen self-made rain gauges with a diameter of 20 cm were laid across the center of the observation plot, and five L. gmelinii trees were selected to install the stemflow collectors. Simultaneously, a tipping bucket rain gauge and three self-made rain gauges were arranged outside the forest. We measured and sampled in situ the solution of bulk precipitation, throughfall, and stemflow after each rainfall event from May 1 to October 30, 2015. After filtering and acidification of the water sample, the concentrations of Na^(+)and K^(+)were measured with a flame atomic absorption spectrophotometer to explore the role of the canopy at different phenological stages(leaf expanding stage, full leaf stage, and senesced leaf stage) on the concentrations and net inputs of Na^(+)and K^(+)in the process of rainfall distribution.【Result】 Throughout the observation period, the concentrations of Na^(+)and K^(+)in rainfall were 0.45 and 1.89 mg/L, in throughfall were 0.44 and 2.48 mg/L, and in stemflow were 1.98 and 18.63 mg/L, respectively. The highest and lowest Na^(+)concentrations in the

关 键 词：城市森林 物候期 穿透雨 树干茎流 水化学 金属元素 养分输入 

分 类 号：S715[农业科学—林学]