关键词: 克拉玛依地区, 热值, 碳含量, 灰分

Abstract:

In this paper, we investigated the caloric values, carbon contents and ash contents of stems from fifty dominant tree species, including thirty-four arbor species and sixteen shrub species, in Karamay region by using calorimetric method, dry combustion method and dry ashing method, respectively. The results showed that caloric values of fifty species were in the range of 17.753-19.112 kJ·g^-1, with the average value of 18.285 kJ·g^-1. Caragana intermedia and Pinus sylvestris var. mongolica had relatively high caloric values, and the means were 19.112 kJ·g^-1 and 19.025 kJ·g^-1, respectively. The carbon contents were in the range of 44.57%-50.35%, with the average value of 48.88%. Ulmus pumila cv. Pendula had the greatest carbon content among the fifty species, with 50.35%, followed by P. sylvestris var. mongolica (50.34%), Lycium ruthenicum (50.11%) and Hippophae rhamnoides (50.00%). The ash contents were in the range of 0.29%-2.34%, with the average value of 0.82%. Populus talassica × P. euphratica had the highest ash content, while P. sylvestris var. mongolica had the lowest. Their values were 2.34% and 0.29%, respectively. On the aspect of life form, the average caloric value of thirty-four arbor species was 18.256 kJ·g^-1, and that of sixteen shrubs was 18.335 kJ·g^-1. The carbon contents of arbors and shrubs were 48.86% and 48.87%, and the ash contents were 0.82% and 0.81%, respectively. There were no significant differences in the caloric values, carbon contents and ash contents between arbors and shrubs (P >0.05). There was highly significantly positive correlation between the caloric values and carbon contents (P <0.01), and there was no significant correlation between the caloric values & ash content and the carbon content & ash content (P >0.05). The 50 tree species had been classified into four categories by cluster analysis. C. intermedia and P. sylvestris var. mongolica belonged to high caloric value and carbon content plants. L. ruthenicum, Euonymus alatus, Syringa oblata, Pyrus betulaefolia, Elaeagnus angustifolia, H. rhamnoides, Morus alba and Prunus salicina were the intermediate caloric value and carbon content plants, which can be used as alternative trees. The other species had relatively low caloric values and carbon contents.

Key words: Karamay agricultural development region, lcaloric value, carbon content, ash content