排水造林对小兴安岭湿地土壤溶解性有机碳生物降解和淋溶的影响

发布时间：2018-05-08 00:10

  本文选题：溶解性有机碳 + 排水造林　； 参考：《环境科学学报》2016年07期

【摘要】：以小兴安岭湿地为研究对象,分析了不同年代排水造林的森林沼泽湿地土壤溶解性有机碳(DOC)含量变化及生物降解特征,探讨了排水造林时间对土壤DOC及无机氮(NH+4-N+NO-3-N)淋溶动态变化的影响.结果表明:1排水造林时间对土壤DOC含量变化影响显著(p0.05).2003年(PS03)、1992年(PS92)、1985年(PS85)排水造林后的人工兴安落叶松湿地土壤DOC含量均低于未排水造林的天然兴安落叶松苔草湿地(XATC),且排水造林时间越长,土壤DOC含量越少.2在生物降解过程中,土壤DOC的变化趋势表现为初期降解速率较快,而后逐渐减慢并趋于稳定.其中周转时间为1 d的易降解DOC所占比重表现为:PS92XATCPS03PS85,表明排水时间达到一定阈值后,易降解DOC部分可能会转化为难降解部分.3在淋溶过程中,随着淋溶次数的增加,淋出液中DOC含量呈现为先增加后减小的趋势,淋溶1 d后,不同年代排水造林的森林沼泽湿地土壤DOC的淋失率表现为:PS85PS92PS03XATC,表明排水造林时间越长,土壤DOC淋失率越大,因此长时间的排水造林改造可能进一步影响土壤养分的贮量及其有效性.
[Abstract]:Taking Xiaoxinganling wetland as the research object, the change of soil dissolved organic carbon (DOC) content and biodegradation characteristics of forest swamp wetland with different years of drainage afforestation were analyzed. The effects of reforestation time on the leaching dynamics of DOC and NH _ 4-N no _ 3-N in soil were studied. The results showed that the effect of reforestation time on soil DOC content was significant (p 0.05). The DOC content of artificial larch wetland after reforestation was lower than that of natural Larix gmelinii wetland after reforestation in 2003 (P < 0.05), P < 0.05 (P < 0.05). XATC, and the longer the drainage and afforestation time, In the process of biodegradation, the change trend of soil DOC content was that the degradation rate of soil DOC was faster at the initial stage, then slowed down and tended to be stable. The proportion of degradable DOC with a turnover time of 1 day was as follows: PS92XATCPS03PS85, which indicated that when the drainage time reached a certain threshold, the easily degradable part of DOC might be transformed into difficult degradation part. 3 in the process of leaching, with the increase of leaching times, The content of DOC in the leachate increased first and then decreased. After 1 day of leaching, the leaching rate of DOC in forested swamp wetland of different years was 1% PS85PS92PS03XATC, which indicated that the longer the time of drainage afforestation, the greater the leaching rate of DOC in soil. Therefore, long-term drainage afforestation may further affect the soil nutrient storage and its effectiveness.
【作者单位】： 黑龙江省普通高等学校地理环境遥感监测重点实验室哈尔滨师范大学;中国气象影视制作中心;
【基金】：国家自然科学基金项目(No.41301082,4157012165) 黑龙江省博士后资助项目(No.LRB13-200)~~
【分类号】：S714
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本文编号：1859070