Nutrient Characteristics of Typical Plant Leaves in Karst and Non-karst Regions of Southwest China
[Objective]Environmental conditions vary greatly between karst and non-karst forests.By comparing the nutrient characteristics of typical plant leaves in the two regions,we explored how plants change the balance between elements to adapt to different environments.[Method]Seven groups of paired plots of karst and non-karst were selected along the latitudinal gradient in Guangxi and Guizhou,and the leaves of dominant species were collected,and their contents of N,P,K,Ca,and Mg elements were de-termined,and the nutrient characteristics,stoichiometric characteristics,interrelationships between ele-ments and the variation characteristics of typical plants in karst and non-karst regions of southwest China were analyzed.[Result]The results showed that:(1)The contents of Ca and Mg in leaves in karst areas(2.19 g/kg and 0.33 g/kg)were significantly higher than those in non-karst areas(0.92 g/kg and 0.20 g/kg),and the contents of K(6.53 g/kg)in karst areas were significantly lower than those in non-karst areas(10.03 g/kg),and there was no significant difference in the contents of N and P.(2)There was a significant positive correlation between N and P,K and Mg in karst and non-karst areas,and P was significantly positively correlated with K and Mg in non-karst areas,and the correlation between P and K was significantly different under different lithologies.(3)In karst areas,N and P were significant-ly positively correlated with latitude,and in non-karst areas,N,P,Ca and Mg were significantly correla-ted with latitude.P was the most sensitive to latitudinal changes;the NP ratio,NK ratio and KP ratio of plant leaves in karst and non-karst areas were significantly correlated with latitude.[Conclusion]Both karst and non-karst plants are low-calcium plants,and P is the most sensitive to latitudinal changes.The absorption of N and P,K,Mg in plants in karst and non-karst areas is in a certain proportion,and so is the absorption of K and Mg.In southwest China,with the increase of latitude,both karst and non-karst plants are limited by N but not by K during their growth.
karsttypical plant leavesstoichiometric characteristics of leaveslatitude
万方数据
维普
