| 摘要: |
| 【目的】研究温度升高对青藏高原和黄土高原土壤有机氮矿化的影响。【方法】采取青藏高原和黄土高原主要农田耕层（0～20 cm）土壤，采用 Stanford 和 Smith 提出的间歇淋洗通气培养法，分别在15，25，35和45 ℃条件下恒温培养210 d，测定培养期间的有机氮矿化量。【结果】青藏高原土壤有机氮净矿化速率为0.16～1.48 mg/(kg·d），黄土高原土壤有机氮净矿化速率为0.12～1.02 mg/(kg·d)；在15～35 ℃的温度条件下，青藏高原和黄土高原土壤铵态氮净矿化累积量对温度变化的响应相对较弱，而在45 ℃时，青藏高原土壤铵态氮净矿化累积量显著增加，并显著高于黄土高原土壤；在15，25和35 ℃时，青藏高原土壤硝态氮净矿化累积量明显高于黄土高原土壤，而在45 ℃时，黄土高原土壤硝态氮净矿化累积量较高。青藏高原土壤矿质氮净矿化累积量在各温度条件下均明显高于黄土高原土壤，且在15 ℃时供试土壤矿质氮矿化累积量最少，在35 ℃时供试土壤矿质氮矿化累积量最多。【结论】青藏高原土壤有机氮矿化对温度升高的响应较黄土高原土壤更为敏感。 |
| 关键词: 青藏高原 黄土高原 土壤氮素矿化 温度 间歇淋洗通气培养法 |
| DOI： |
| 分类号: |
| 基金项目:黄土高原土壤侵蚀与旱地农业国家重点实验室基金项目(10501-247）；国家重点实验室专项课题（10502-Z4） |
|
| Effect of temperature on nitrogen mineralization on the Qinghai-Tibet and the Loess Plateau |
|
XING Shunlin1,2, LIU Yi3,4, LI Shiqing1,2
|
|
1.State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A&F University;2.College of Forestry ,Northwest A&F University;3.Wuhan Botanical Garden, Chinese Academy of Sciences;4.Key Laboratory of Aquatic Plant Biology and Watershed Ecology, Chinese Academy of Sciences
|
| Abstract: |
| 【Objective】Temperature impact on mineralization of soil organic nitrogen were studied by comparing the temperature impact on soil nitrogen mineralization of the Qinghai-Tibet and the Loess Plateau.【Method】The alternate leaching aerobic incubation method proposed by Stanford and Smith were adopted.The arable soil of the Qinghai Tibet and the Loess Plateau(0-20 cm) was incubated for 210 d under the constant temperature conditions at 15,25,35 and 45 ℃,and during cultivation the organic nitrogen mineralization were determined.【Result】 The soil net mineralization rates of Qinghai-Tibet Plateau ranged from 0.16 to 1.48 mg/(kg·d) and that of Loess Plateau varied from 0.12 to 1.02 mg/(kg·d).In 15-35 ℃,the soil ammonium N net mineralization accumulation of the Qinghai-Tibet and the Loess Plateau responded to temperature change relatively weakly,while the soil ammonium N net mineralization accumulation of Qinghai-Tibet Plateau increased significantly at 45 ℃,much higher than that of Loess Plateau.The soil nitrate N net mineralization accumulation of the Qinghai Tibet Plateau was significantly higher than that of the Loess Plateau at 15,25 and 35 ℃,while at 45 ℃ nitrate N net mineralization accumulationof soil nitrate nitrogen of Loess Plateau was higher.The Qinghai-Tibet Plateau’s accumulation was significantly higher than that of the Loess Plateau’s in various temperature conditions.The mineralization accumulation of mineral nitrogen of the tested soil was the least at 15 ℃,while it was up to the maximum at 35 ℃.【Conclusion】 We draw a conclusion that the mineralization of soil organic nitrogen in Qinghai-Tibet Plateau responded more sensitively to temperature than the Loess Plateau. |
| Key words: Qinghai-Tibet Plateau Loess Plateau N mineralization temperature alternate leaching aerobic incubation |
