Calorific Values of Grassland Plant Population and Functional Groups in the Agro-pastoral Ecotone of Inner Mongolia and Liaoning Province Border北大核心CSCD

Agro-pastoral ecotone is an important ecological barrier in China,and its ecological environment problems are becoming increasingly prominent. In this study,61 species of plants in 27 grassland plots in the agro-pastoral ecotone of Inner Mongolia and Liaoning border were collected for calorific value analysis under the random sampling condition. The changes of calorific value of plants in different types of functional groups were explored to provide scientific data and research support for energy fixation and rational use of grassland resources in the agro-pastoral ecotone. The results showed that:The average calorific value of 61 species was 17.14 KJ·g-1. Among them,Salsola collina had the lowest calorific value (12.82 KJ·g-1),the caloric value of Polygala tenuifolia was the highest (20.07 KJ·g-1),and the total calorific value was normal distribution. Comparing the caloric values of different life-type functional groups,the caloric value of annuals and biennials was significantly lower than perennial grasses and shrubs (P<0.05),which had no significant difference with sub-shrubs and perennial forbs. There was no significant difference among perennial grasses,shrubs,perennial weeds and semi-shrubs (P>0.05). There was no significant difference in caloric value between different water ecological functional groups (P>0.05). The plant caloric mean value of the Xero-mesophytes was slightly lower than other groups. There was no significant difference in calorific value among Liliaceae,Leguminosac,Gramineae,Compositae and Rosaceae,and the caloric value of Chenapodiaceae was significantly lower than other families (P<0.05). There was a significant positive correlation between plant calorific value and carbon content (P<0.05). © 2019 China Agricultural University. All rights reserved.