摘要
山原红壤是一种地带性古土壤,是中国退化最为严重的土壤之一,速效养分是土壤肥力的重要指标。通过对云贵高原山原红壤区同一坡面不同土地覆被类型土壤剖面速效养分含量分析结果表明：山原红壤速效养分以表层含量最高,但多低于云贵高原其他土壤;从有植被退化至无植被的过程中,0~30 cm土层范围内土壤速效养分变异最为敏感,严重退化的、多年难以生长植被的＂红裸土＂明显呈现低铵态氮、高硝态氮和高速效钾的特征,与有植被山原红壤差距较大,三者可以考虑作为指示山原红壤退化的养分指标;而有植被山原红壤中,0~30 cm深度范围内不同剖面同一土层铵态氮、硝态氮、速效钾、速效磷含量分别呈现＂火棘灌丛〉云南松林〉草地、火棘灌丛〉草地〉云南松林、火棘灌丛〉草地〉云南松林、草地〉云南松林〉火棘灌丛＂的特点,说明山原红壤速效养分变化难以准确反映植被退化的先后秩序。研究还表明：不同覆被条件无耕作干扰下的山原红壤各土体均缺磷,除＂红裸土＂外均缺钾。因而,＂红裸土＂生态恢复中,补充磷肥是关键,而对于草地和林地,人工补充钾肥、磷肥是改善土壤养分条件的关键措施。
Mountain red earth is a kind of zonal paleosol and is also among the ones which have suffered from the most serious soil degradation in China. The available nutrition is an important index of soil fertility. Analysis of the contents of the available nutrients on the same slope of the original different land cover types in Yun-gui plateau red earth region show that the contents of the available nutrients in the surface layer of mountain red earth is the highest,but it is less than many other soils of Yun-gui plateau. In the process of vegetation degradation,the variation of the available nutrients in the layer of 0- 30 cm is very sensitive. The‘red-bare-soil＇,which has suffered from the most serious degradation and can hardly bear any plant for many years,now presents the characteristics of high rapid available potassium,nitrate nitrogen and low ammonium nitrogen which are quite different from the original vegetation mountain red soil,so the three nutrients can be considered as indicating indexes of the mountain red earth degeneration; While in the mountain red earth with vegetation,the contents of ammonium nitrogen,nitrate nitrogen,available potassium and available phosphorus in the profile of soil from 0 to 30 cm present the tendency of‘Pyracantha shrub 〉Yunnan pine forest 〉grassland and,Pyracantha shrub 〉grassland and 〉Yunnan pine forest,grassland and 〉Yunnan pine forest 〉Pyracantha shrub＇,respectively,which shows that the available nutrients content of mountain red earth is difficult to accurately reflect the sequencing of vegetation degradation. The study also indicates that the whole red earth under different cover conditions without tillage disturbance is lack of phosphorus; all the mountain red earth is poor in potassium except the‘red bare soil＇. Thus,in the process of‘red bare soil＇ecological restoration,added phosphate is the key measure. As for the grass land and woods,one of the most efficient measures is to use phosphorus and potassium fertilizer to improve soil nutrient c
出处
《西南农业学报》
CSCD
北大核心
2016年第1期120-125,共6页
Southwest China Journal of Agricultural Sciences
基金
国家自然科学基金(41061021)
云南省科技计划项目(2012CA024)
关键词
山原红壤
土壤剖面
速效养分
Mountain red earth
Soil profile
Available nutrients
