内蒙古额尔古纳草甸草原植物器官热值研究OA

The aim of this study was to investigate the energy fixation and allocation mechanisms in meadow steppe ecosystems.To this end,we systematically analyzed the calorific values of 36 plant species growing on the Erguna Meadow Steppe,Inner Mongolia.We analyzed variations in calorific values and energy allocation patterns across plant organs,functional groups(Fabaceae,Poaceae,forbs),and hydric ecological types(xerophytes,meso-xerophytes,xero-mesophytes,mesophytes,wet-mesophytes).The results showed that:1)The average calorific value of the 36 plant species was 17.31 kJ·g-1.Among the plant organs,fruit had the highest average calorific value,followed by flowers and leaves,while stems had the lowest,with all differences being significant(P<0.05).Among the major families,Fabaceae exhibited the highest calorific values,significantly higher than those of Asteraceae,Ranunculaceae,and Amaryllidaceae(P<0.05),but there was no significant difference in calorific value between Rosaceae and Amaryllidaceae.2)Among the functional groups,Fabaceae had significantly higher calorific values than Poaceae and forbs(P<0.05).In Fabaceae,calorific values were significantly higher for the leaf than for the other organs(P<0.05).In Poaceae,the calorific values of the leaves were higher than those of the stems;in forbs,the calorific values of flowers and fruit were significantly higher than those of stems and leaves(P<0.05).3)The whole-plant calorific values did not differ significantly among hydric ecological types(P>0.05).However,except for meso-xerophytes,all other hydric ecological types showed significantly higher calorific values for flowers and fruits than for stems and leaves(P<0.05),indicating that calorific values in hydric ecological types respond significantly at the organ level.4)Whole-plant calorific values were significantly positively correlated with carbon content,suggesting that carbon content is a key factor influencing plant energy storage.Similarly,calorific values of plant organs were also significantly positively correlated with carbon content,but the strength of the correlation varied among organs(flowers>leaves>stems>fruits),with the strongest correlation in flowers(r=0.91)and the weakest in fruit(r=0.79).