白桦次生林降雨水化学及养分输入特征  

Hydro-chemical and nutrient importing characteristics of precipitation in secondary Betula platyphylla forests in northern Great Xing 'an Mountains,northeastern China

作　　者：刘茜[1] 满秀玲[1] 田野宏[1] 

机构地区：[1]东北林业大学林学院

出　　处：《北京林业大学学报》2015年第8期83-89,共7页Journal of Beijing Forestry University

基　　金：国家自然科学基金项目(31170420)

摘　　要：通过对大兴安岭北部白桦次生林林外降雨、穿透雨、树干径流和枯透水进行野外观测、取样及室内水化学测定,研究了白桦次生林降雨养分输入特征。结果表明:大兴安岭漠河地区大气降雨呈中性,p H为7.0,TDS值为19mg/L。在白桦林降雨再分配过程中,p H与TDS均表现为先降低后升高的趋势,最低值都出现在树干径流中,分别为5.3、15 mg/L。而p H和TDS的最高值分别出现在大气降雨和枯透水中。阴离子中,F-及SO2-4最高值均出现在树干径流中,其他阴离子浓度则在枯透水中最高,且其中NO-3变化最大,最高、最低相差100.4倍。金属元素中,Na+、Zn2+及Mn元素最高值均出现在树干径流中,其他元素浓度则在枯透水中最高。而最低值几乎均出现于大气降雨(除Ca2+、Cu2+外)中。大气降雨养分输入量为95.414 kg/hm2,降雨穿过林冠层后,F-、Cl-、NO-3、Ca2+、Fe元素及Cu2+含量均有不同程度降低,其余元素则有所增加,使林内雨养分总量降为93.557 kg/hm2。林内雨穿过枯落物层后,除Na+含量较林内雨降低外,其他元素含量均升高,养分总输入量升高了72.149 kg/hm2。与大气降雨输入量相比,枯透水输入量则增加了70.296 kg/hm2,其中Cl-、Na+和Cu2+含量低于大气降雨,其他元素则有不同程度增加。最终大气降雨通过白桦次生林后输入土壤养分总量为165.711 kg/hm2,其中阴离子输入量为37.823 kg/hm2,金属元素输入量为127.888 kg/hm2。We observed and sampled the precipitation, throughfall, stem flow and litter water in secondary Betula platyphylla forests in northern Great Xing＇ an Mountains and measured their hydro-chemical properties, in order to study the nutrient importing characteristics of precipitation. The results showed that ： the precipitation in Mohe area was neutral with pH value of 7.0 and TDS of 19 mg/L. The pH and TDS showed a tendency of increasing first and then declining, with the minimum values of pH and TDS both in the stem flow, 5.3 and 15 mg/L, respectively, while the maximum value of pH was in the rainfall and that of TDS in litter water. The highest concentrations of F- and SOl- were found in the stem flow, and those of other anions in the litter water. Among the anions, the concentration of NO3- had the greatest variation, with the maximum 101.4 times as high as the minimum. As for the metallic elements, the highest concentrations of Na ＋ , Zn2＋and Mn occurred in the stem flow, and those of the others in the litter water, while the lowest concentrations of them were almost all in rainfall （ except for Ca2 ＋ and Cu2＋ ）. The overall nutrient input of precipitation was 95. 414 kg/ha. After the rain falls through forest canopy, the concentrations of F-, CI-, NO/, Ca2~, Fe and Cu2~ decreased to different degrees whereas the others increased, and the total nutrient content of throughfall was reduced to 93. 557 kg/ha.After passing through the litter layer, except for Na ＋ , the contents of other elements increased to varying degrees, and the total amount of nutrient input was increased by 72. 149 kg/ha. Compared with the rainfall input, litter water input was increased by 70. 296 kg/ha, in which C1- , Na ＋ and Cu2＋ contents were lower than those in the rainfall, while other elements had increased to different degrees. Eventually the total amount of nutrient input that the rainfall brought to the soil after passing through the secondary forests was 165. 711 kg/ha, the amount of anions input was 37. 823 kg

关 键 词：大兴安岭北部 白桦次生林 降雨再分配 水化学 养分输入 

分 类 号：S715.2[农业科学—林学]