本溪山区森林枯落物对水质的影响

Effect of Forest Litter on Water Quality in Mountains of Benxi City

以本溪山区主要水源涵养林红松、落叶松、蒙古栎、水曲柳、核桃楸纯林为研究对象,运用定位观测法,对5种类型林分的林外雨与枯落物渗透雨(枯透雨)的水质进行了研究,以及利用5种类型林分之间枯落物渗透水的水质对比,测定林外降雨及各林分枯落物渗透水的pH值、硝酸盐(以N计)、氨氮(以N计)、硫酸盐(以SO_4^(2-)计)、全氮(TN)、全磷(TP)、氟离子(F^-)、氯离子(Cl^-)、钙(Ca^(2+))、钠(Na^+)、镁(Mg^(2+))、钾(K^+)等12种指标,结果表明:大量化学元素和离子通过枯落物后均显著增加,其中变幅最大的K^+,浓度为4.19mg·L^(-1),是林外雨20倍。林外雨各指标浓度依次为SO_4^(2-)>TN>Ca^(2+)>Cl^->Na^+>NH_3-N>NO_3^-N>Mg^(2+)>K^+>F^->TP;枯透雨各指标浓度依次为SO_4^(2-)>Ca^(2+)>TN>NO_3^-N>Cl^->K^+>Mg^(2+)>NH_3-N>TP>F^->Na^+。枯透雨中SO_4^(2-)浓度最高,为12.59mg L^(-1);TP浓度最小,为0.25mg L^(-1)。5种纯林在调查期间林外雨和枯透雨的pH趋于中性,而在经过枯枝落叶层的淋溶后,有明显的酸化现象,pH范围在5.1~6.6。

Taking the main water conservation forest--Pinus koraiensis,Larix gmelinii,Quercus mongolica,Fraxinus mandschurica ＆Juglans mandshurica in Benxi mountains as the research object,with the method of the locating observation,water quality of rainfall outside the forest and permeating water of litters of five types of forest was studied.Twelve kinds of digital number （DN）--pH value,nitrate （counted by nitrogen）,ammonia nitrogen （counted by nitrogen）,sulfate （SO42-）,total nitrogen （TN）,total phosphorus （TP）,fluorineion （F-）,chlorine （Cl-）,calcium （Ca2＋）,sodium （Na＋）,magnesium （Mg2＋）,kalium （K＋） of rainfall outside the forest and permeating water were determined.Result show that： mass chemical elements and ions by litter significantly increase.The biggest range is K＋,whose concentration being 4.19 mg＆#183;L-1,which is 20 times higher than the rainfall outside the forest;concentration of each index for the rainfall outside the forest is： SO42-＞TN＞ Ca2＋＞Cl-＞Na＋＞NH3-N＞ NO3-N＞Mg2＋＞K＋＞F-＞TP;each concentration index of rain in filtration chemical element is： SO42-＞Ca2＋＞TN＞NO3-N＞Cl-＞K＋＞Mg2＋＞NH3-N＞TP＞F-＞Na＋.The concentration of SO42-is the highest,being 12.59 mg＆#183;L-1;the concentration of TP is the smallest,being 0.25 mg＆#183;L-1.During the survey period,the pH value of rainfall outside the forest and soaker tend to be neutral,but after the leaching of litter layer,there are obvious phenomenon of acidification,the pH range is from 5.1 to 6.6.