CAJ | 학술논문

选取内蒙古锡林郭勒典型草原区两种不同退化程度草原群落(轻度和重度退化草原群落),设置氮素添加梯度实验(分别添加NH4NO30,30,50,80 g·m-2),分析退化草原土壤有机质含量对氮素添加的响应,意图找出氮肥作用于不同退化程度草原时的最适值。结果表明,不同退化程度的草原对于氮素添加的响应不同：对于轻度退化草原,氮素添加对土壤有机质的影响主要集中在0~20 cm土层,30 g· m-2处理时土壤有机质显著高于其他3个氮素水平,氮素的添加显著提高土壤有机质含量,说明氮素是轻度退化草原主要的限制因子；对于重度退化草原,当施氮量为30 g·m-2时,0~10 cm层土壤有机质含量相对较高,但没有达到统计学上的显著差异。土壤有机质在氮素添加梯度下各层变化不显著,说明氮素不是重度退化草原的主要限制因子。
선취내몽고석림곽륵전형초원구량충불동퇴화정도초원군락(경도화중도퇴화초원군락),설치담소첨가제도실험(분별첨가NH4NO30,30,50,80 g·m-2),분석퇴화초원토양유궤질함량대담소첨가적향응,의도조출담비작용우불동퇴화정도초원시적최괄치。결과표명,불동퇴화정도적초원대우담소첨가적향응불동：대우경도퇴화초원,담소첨가대토양유궤질적영향주요집중재0~20 cm토층,30 g· m-2처리시토양유궤질현저고우기타3개담소수평,담소적첨가현저제고토양유궤질함량,설명담소시경도퇴화초원주요적한제인자；대우중도퇴화초원,당시담량위30 g·m-2시,0~10 cm층토양유궤질함량상대교고,단몰유체도통계학상적현저차이。토양유궤질재담소첨가제도하각층변화불현저,설명담소불시중도퇴화초원적주요한제인자。
In this study we selected two communities in different degree of degraded grasslands ( lightly degraded grassland and heavily degraded grassland ) in Xilin Gol, Inner Mongolia. Then we set up nitrogen addition rate test (respectively adding NH4NO3 0g/m2, 30g/m2, 50g/m2 , 80g/m2 ) to analyze the response of the soil organic matter content on the nitrogen adding gradient,and find the optimal values of nitrogen fertilizer applied at different degree of degraded grassland. The results showed that the response of the different degree of degraded grassland to nitrogen addition is different. For lightly degraded grassland, the response of nitrogen addition on soil organic matter is mainly concentrated in the 0-20cm layer, and nitrogen addition at a rate of 30g/m2 , soil organic matter was significantly higher than the other three nitrogen levels, nitrogen addition significantly increased soil organic matter content, which meant that nitrogen is the major limiting factor in lightly degraded grassland. For heavily degraded grassland, when ni-trogen rate was 30g/m2 , 0-10cm layer of soil organic matter content is relatively high, but did not reach a statistically significant difference. Adding nitrogen gradient did not change soil or-ganic matter content significantly, which meant that nitrogen is not the main limiting factor in heavily degraded grassland.