不同利用方式下亚热带花岗岩流域元素收支平衡及其对土壤酸化的影响

发布时间：2018-08-11 13:02

【摘要】：选取亚热带花岗岩区不同利用方式下的3个相邻小流域(F:100%森林;FA1:82%森林+18%农田;FA2:76%森林+24%农田),通过定期监测与分析雨水和径流水的元素组成,获得了流域尺度元素的降水输入与径流输出特征,在此基础上分析了元素收支平衡及其对土壤酸化的影响。结果表明:雨水中离子输入总量为181.74 kg/(hm~2·a),夏季输入量约占全年输入量的45%,Ca~(2+)、Na~+和NH_4~+约占阳离子输入总量的80%,SO_4~(2 )和NO_3~ 约占阴离子输入总量的74%。F、FA1和FA2流域径流水中离子输出总量分别为236.81,153.17和243.36 kg/(hm~2·a),夏季输出量约占全年输出量的39%~47%,Ca~(2+)和Na~+约占阳离子输出总量的81%~86%,SO_4~(2 )和NO_3~ 约占阴离子输出总量的65%~70%。降水和径流水的元素收支平衡表明,F、FA1和FA2流域中SO_4~(2 )、NO_3~ 、Cl~ 、NH_4~+和H~+均表现为净输入,其中SO_4~(2 )的净滞留量最高,分别为13.7、30.43和20.49 kg/(hm~2·a);而Ca~(2+)、Mg~(2+)和Na~+均表现为净输出,其中Na~+的净输出量最高,分别为28.99、14.96和31.76 kg/(hm~2·a)。F、FA1和FA2流域内酸雨直接输入的H~+为818 mol/(hm~2·a),而流域内氮素转化产生的H~+分别为396、389和401 mol/(hm~2·a),占H~+输入总量的32%~33%。F、FA1和FA2流域的土壤酸化速率分别为996、1 069和1 035 mol/(hm~2·a),表明即使不考虑农业施肥的情况下农林复合流域(FA1和FA2)的土壤酸化速率仍高于森林流域(F)。
[Abstract]:Three adjacent small watersheds (F: 100% forest, 18% farmland, FA2: 76% forest, 24% farmland) were selected under different utilization patterns in subtropical granite region. The composition of Rain Water and runoff water elements were monitored and analyzed regularly. The characteristics of precipitation input and runoff output of elements in watershed scale were obtained. Based on this, the balance of element budget and its influence on soil acidification were analyzed. The results show that the total amount of ion input in Rain Water is 181.74 kg/ (hm~2 a), summer input accounts for about 45% of the annual input). Ca2 + Na ~ and NH ~ 4 ~ account for 80% of the total cationic input quantity. So _ 4 ~ (2) and no _ 3 ~ + account for about 74. FFA1 and FA2 runoff water ions. The total output is 236.81153.17 and 243.36 kg/ respectively (the summer output of hm~2 a), accounts for about 39% of the total output in the whole year), and the Ca2 and Na ~ (2) account for 81 ~ (86) so ~ (2) and no ~ (3) ~ of the total anion output of the total cationic output. The balance of element budget in precipitation and runoff water shows that so _ 4 ~ (2) O _ (2) O _ 4 ~ (2) C _ (2) C _ (2) and H ~ (+) are net inputs, and so _ 4 ~ (2) ~ (2) is the highest in the total number of kg/ (hm~2 a);) and Ca ~ (2) (mg ~ (2) and Na ~ (2), respectively, and the net retention of so ~ (4 ~ (2) is the highest. The net output of Na ~ is the highest. The direct input of H ~ from acid rain in the basins of 28.99 and 31.76 kg/ (hm~2 a). FGFA1 and FA2 were 818 mol/ (hm~2 a), respectively, and the H- ~ of N transformation in the basin were 396389 and 401 mol/ (hm~2 a), accounted for 32 ~ 33% of the total input of H ~, respectively). The soil acidification rates of FA2 and FA2 basins were 9966 ~ 1 069 and 1 035 mol/ (hm~2 a), respectively. The results show that the soil acidification rate of agroforestry complex watershed (FA1 and FA2) is higher than that of forest basin (F). Even if agricultural fertilization is not considered.
【作者单位】：中国科学院地理科学与资源研究所生态系统网络观测与模拟院重点实验室;土壤与农业可持续发展国家重点实验室(中国科学院南京土壤研究所);中国科学院大学;
【基金】：国家自然科学基金国际合作与交流项目(41571130051) 中国科学院南京土壤研究所土壤与农业可持续发展国家重点实验室开放基金项目(Y20160003)资助
【分类号】：S153.4

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