Little attention has been paid to the role of soil organic matter (OM) in the formation of pedogenic carbonate in desert soils. The relationships among soil OM, soil dehydrogenase activity (DHA), and soil CaCO3 in...Little attention has been paid to the role of soil organic matter (OM) in the formation of pedogenic carbonate in desert soils. The relationships among soil OM, soil dehydrogenase activity (DHA), and soil CaCO3 in a plant community dominated by Artemisia ordosica, located on the eastern boundary of Tcngger Desert in the Alxa League, Inner Mongolia, China, were studied to understand whether OM was directly involved in the formation of pedogenic carbonate. The results showed that DHA and CuCO3 positively correlated with OM content, and DHA, OM, and CaCO3 were correlated with each other in their spatial distribution, indicating that abundant OM content contributed to the formation of CaCO3. Therefore, the formation of pedogenic CaCO3 was a biotic process in the plant community dominated by A. ordosica.展开更多
OBJECTIVE: To study the effects of the drying processing in terms operational parameters on the bio- active constituents of six YuanzhJ (Radix Palygalae) samples across China. METHODS: Six Yuanzhi (Radix Palygala...OBJECTIVE: To study the effects of the drying processing in terms operational parameters on the bio- active constituents of six YuanzhJ (Radix Palygalae) samples across China. METHODS: Six Yuanzhi (Radix Palygalae) samples were investigated using thermogravimetry analysis. The heating courses were set in two ways: the temperature-programmed process from room temperature to 150℃ ,and the constant-temperature course at 50℃, 70℃ and 90℃. RESULTS: The peak temperature of six Yuanzhi (Radix Palygalae) samples ranged from 78℃ to 88℃. The mass loss rate of Yuanzhi (Radix Palygalae) alcohol-soluble extract was significantly increased when heated at 90℃. Four types of bioactive ingredients were detected in volatile oils of Yuanzhi (Radix Palygalae) sample from Shanxi province by Gas Chromatography-mass spectrometry analysis. Fourier Transform Infrared Spectroscopy results showed that the drying temperature exerted a great influence on types and amount of ingredients of Yuanzhi (Radix Palygalae). The kinetic study showed that the constant-temperature drying process of Yuanzhi Radix Palygalae) samples could be well de- scribed by the Page Model, especially for the drying process at 50~C, in which R2 and SD values were more than 0.98 and less than 0.04, respectively.The drying constant k of three Yuanzhi (Radix Palygalae) samples from Shanxi, Gansu and Shaanxi provinces in China was corresponding to the Arrhenius equation, and their activation energies were 28.07, 2.5.38 and 21.48 kJ/mol, respectively. CONCLUSION: The drying process of Yuanzhi (Radix Palygalae) was very important for bioactive ingredients improvement in Yuanzhi (Radix Palygalae). Temperature was a thermodynamic property significantly affecting the process.展开更多
基金Project supported by the National Basic Research Program (973 Program) of China (No. 2007CB106802)the National Natural Science Foundation of China (No. 30970546)
文摘Little attention has been paid to the role of soil organic matter (OM) in the formation of pedogenic carbonate in desert soils. The relationships among soil OM, soil dehydrogenase activity (DHA), and soil CaCO3 in a plant community dominated by Artemisia ordosica, located on the eastern boundary of Tcngger Desert in the Alxa League, Inner Mongolia, China, were studied to understand whether OM was directly involved in the formation of pedogenic carbonate. The results showed that DHA and CuCO3 positively correlated with OM content, and DHA, OM, and CaCO3 were correlated with each other in their spatial distribution, indicating that abundant OM content contributed to the formation of CaCO3. Therefore, the formation of pedogenic CaCO3 was a biotic process in the plant community dominated by A. ordosica.
基金Supported by the National Science and Technology Support Program of the Ministry of Science and Technology of the People's Republic of China (No.2011BAI07B05)Shanxi Science and Technology Tackling Fund (No.20100311090,20130313015-2)Department of Health of Shanxi province Tackling Fund (No.200834)
文摘OBJECTIVE: To study the effects of the drying processing in terms operational parameters on the bio- active constituents of six YuanzhJ (Radix Palygalae) samples across China. METHODS: Six Yuanzhi (Radix Palygalae) samples were investigated using thermogravimetry analysis. The heating courses were set in two ways: the temperature-programmed process from room temperature to 150℃ ,and the constant-temperature course at 50℃, 70℃ and 90℃. RESULTS: The peak temperature of six Yuanzhi (Radix Palygalae) samples ranged from 78℃ to 88℃. The mass loss rate of Yuanzhi (Radix Palygalae) alcohol-soluble extract was significantly increased when heated at 90℃. Four types of bioactive ingredients were detected in volatile oils of Yuanzhi (Radix Palygalae) sample from Shanxi province by Gas Chromatography-mass spectrometry analysis. Fourier Transform Infrared Spectroscopy results showed that the drying temperature exerted a great influence on types and amount of ingredients of Yuanzhi (Radix Palygalae). The kinetic study showed that the constant-temperature drying process of Yuanzhi Radix Palygalae) samples could be well de- scribed by the Page Model, especially for the drying process at 50~C, in which R2 and SD values were more than 0.98 and less than 0.04, respectively.The drying constant k of three Yuanzhi (Radix Palygalae) samples from Shanxi, Gansu and Shaanxi provinces in China was corresponding to the Arrhenius equation, and their activation energies were 28.07, 2.5.38 and 21.48 kJ/mol, respectively. CONCLUSION: The drying process of Yuanzhi (Radix Palygalae) was very important for bioactive ingredients improvement in Yuanzhi (Radix Palygalae). Temperature was a thermodynamic property significantly affecting the process.