This study was conducted in Xinkou Experimental Forestry Farm of Fujian Agricultural and Forestry University, Sanming, Fujian Province in January 1999. Taking pure stand of Chinese fir as control, the authors measured...This study was conducted in Xinkou Experimental Forestry Farm of Fujian Agricultural and Forestry University, Sanming, Fujian Province in January 1999. Taking pure stand of Chinese fir as control, the authors measured and studied the content of organic carbon, content of humic acid (HA), ratio of HA to fulvic acid (FA), and the characteristics of infrared light spectrum and visible light spectrum of soil humus in the mixed forest of Chinese fir and Tsoong?tree. Compared to humus composition in the pure stand of Chinese fir, the content of soil organic C, HA content, and the E4 value of HA for different layers of soil, except for the ratio of HA to FA, showed a significant increase in the mixed forest, while the ratios of E4 to E6 had a little decrease. The infrared light spectrum of humic acid had an absorptive peak at 1650 cm-1. It is concluded that the levels of humification and aromaticity of soil humus are higher in the mixed forest, which is favorable for the improvement of soil structure and nutrient supply, thus improving the soil fertility to a certain degree.展开更多
A new baccharane-type triterpene, 3-acetoxy-9(11)-baccharene(1),as well as a known compound, a-amyrin(2), has been isolated from the ether extract of the roots of Saussurea lappa C. B. Clarke. The structure of the new...A new baccharane-type triterpene, 3-acetoxy-9(11)-baccharene(1),as well as a known compound, a-amyrin(2), has been isolated from the ether extract of the roots of Saussurea lappa C. B. Clarke. The structure of the new compound was identified by spectrum analysis.展开更多
A study was conducted to detect the effect of water extracts from different parts such as root, bark, branch and leaf, of adult larch, Larix gmelini, trees on growth of Manchurian walnut, Juglans mandshudca, seedlings...A study was conducted to detect the effect of water extracts from different parts such as root, bark, branch and leaf, of adult larch, Larix gmelini, trees on growth of Manchurian walnut, Juglans mandshudca, seedlings and the allelopathy between the two tree species. Four concentrations （100 g. kg i, 50 g. kg^-1, 25 g. kg^-1 and 12.5 g. kg^-1） were prepared for each kind of extracts. Result showed that the water extracts with low and moderate concentrations accelerated the growth of collar diameter and increased biomass and root/shoot ratio of walnut seedlings. The water extracts from branches and barks with low and moderate concentrations accelerated the height growth of the seedlings, while those from leaves and roots slightly decreased the height growth of seedlings. The fact that application of water extracts of larch improved the growth of Manchurian walnut attributes possibly to the allelopathy between the two tree species.展开更多
New Zealand, as a nation, has been in existence for less than two cen- turies-whether one dates its assumption of sovereignty to the 1835 Declaration of Independence by the Confederation of United Tribes, the 1840 Tre...New Zealand, as a nation, has been in existence for less than two cen- turies-whether one dates its assumption of sovereignty to the 1835 Declaration of Independence by the Confederation of United Tribes, the 1840 Treaty of Waitangi between Maori and the British Crown, or its attainment of Dominion status in 1907. The question of a separate cultural identity for this post-colonial, multi-cultural country has therefore always been a complex one, and one which has had a strong influence on much of our artistic expression to date： particularly, perhaps because of its inherent tendency towards the self-analysis only really possible within language, literature. The fact that our most famous locally born writer to date, Katherine Mansfield, specialised in the short story has certainly helped to establish that as a vital genre here. This paper accordingly takes four successive anthologies of local short fiction--Frank Sargeson＇s Speaking for Ourselves （1945）, Michael Morris- sey＇s The New Fiction （1985）, Warwick Bennett and Patrick Hudson＇s Rutherford＇s Dreams （1995）, and Tina Shaw and Jack Ross＇s Myth of the twenty-firstCentury （2006）--and attempts to characterise their respective, overlapping visions of New Zealand identity by conducting a close reading of a representative story from each of them. The essay concludes with a call for a new anthology which might attempt to give expression to this series of gradual erosions of our initial cultural certainties into something more adequate to the realities of our place in the world, both geo- graphically and culturally.展开更多
Charcoals collected from the middle-late Pliocene sediments of the Taigu Basin,Shanxi Province,China,have been identified as Ulmus sp.(Ulmaceae),Prunus sp.,Maloidoxylon sp.(Rosaceae),and Maclura sp.(Moraceae).These ta...Charcoals collected from the middle-late Pliocene sediments of the Taigu Basin,Shanxi Province,China,have been identified as Ulmus sp.(Ulmaceae),Prunus sp.,Maloidoxylon sp.(Rosaceae),and Maclura sp.(Moraceae).These taxa,along with the previously known fossils,indicate the occurrence of temperate climate and local wildfire at that time.Charcoals of trees and/or shrubs and the morphological changes of these charcoals demonstrate that crown fires and surface fires occurred in the Taigu Basin during the middle-late Pliocene.展开更多
基金Foundation item:This paper was supported by Natural Science Foundation of Fujian Province (B0110025) and Foundation for University Key Teacher by the Ministry of Education.
文摘This study was conducted in Xinkou Experimental Forestry Farm of Fujian Agricultural and Forestry University, Sanming, Fujian Province in January 1999. Taking pure stand of Chinese fir as control, the authors measured and studied the content of organic carbon, content of humic acid (HA), ratio of HA to fulvic acid (FA), and the characteristics of infrared light spectrum and visible light spectrum of soil humus in the mixed forest of Chinese fir and Tsoong?tree. Compared to humus composition in the pure stand of Chinese fir, the content of soil organic C, HA content, and the E4 value of HA for different layers of soil, except for the ratio of HA to FA, showed a significant increase in the mixed forest, while the ratios of E4 to E6 had a little decrease. The infrared light spectrum of humic acid had an absorptive peak at 1650 cm-1. It is concluded that the levels of humification and aromaticity of soil humus are higher in the mixed forest, which is favorable for the improvement of soil structure and nutrient supply, thus improving the soil fertility to a certain degree.
基金This work was supported by the Kunming Institute of Botany,Chinese Academy of Sciences.
文摘A new baccharane-type triterpene, 3-acetoxy-9(11)-baccharene(1),as well as a known compound, a-amyrin(2), has been isolated from the ether extract of the roots of Saussurea lappa C. B. Clarke. The structure of the new compound was identified by spectrum analysis.
基金This paper was supported by National Natural Science Foundation of China （No. 30400341） and Heilongjiang Provincial Science Foundation （No. C0320）Acknowledgement I thank Dr. YAN Xiu-feng for his help and guidance.
文摘A study was conducted to detect the effect of water extracts from different parts such as root, bark, branch and leaf, of adult larch, Larix gmelini, trees on growth of Manchurian walnut, Juglans mandshudca, seedlings and the allelopathy between the two tree species. Four concentrations （100 g. kg i, 50 g. kg^-1, 25 g. kg^-1 and 12.5 g. kg^-1） were prepared for each kind of extracts. Result showed that the water extracts with low and moderate concentrations accelerated the growth of collar diameter and increased biomass and root/shoot ratio of walnut seedlings. The water extracts from branches and barks with low and moderate concentrations accelerated the height growth of the seedlings, while those from leaves and roots slightly decreased the height growth of seedlings. The fact that application of water extracts of larch improved the growth of Manchurian walnut attributes possibly to the allelopathy between the two tree species.
文摘New Zealand, as a nation, has been in existence for less than two cen- turies-whether one dates its assumption of sovereignty to the 1835 Declaration of Independence by the Confederation of United Tribes, the 1840 Treaty of Waitangi between Maori and the British Crown, or its attainment of Dominion status in 1907. The question of a separate cultural identity for this post-colonial, multi-cultural country has therefore always been a complex one, and one which has had a strong influence on much of our artistic expression to date： particularly, perhaps because of its inherent tendency towards the self-analysis only really possible within language, literature. The fact that our most famous locally born writer to date, Katherine Mansfield, specialised in the short story has certainly helped to establish that as a vital genre here. This paper accordingly takes four successive anthologies of local short fiction--Frank Sargeson＇s Speaking for Ourselves （1945）, Michael Morris- sey＇s The New Fiction （1985）, Warwick Bennett and Patrick Hudson＇s Rutherford＇s Dreams （1995）, and Tina Shaw and Jack Ross＇s Myth of the twenty-firstCentury （2006）--and attempts to characterise their respective, overlapping visions of New Zealand identity by conducting a close reading of a representative story from each of them. The essay concludes with a call for a new anthology which might attempt to give expression to this series of gradual erosions of our initial cultural certainties into something more adequate to the realities of our place in the world, both geo- graphically and culturally.
基金supported by National Natural Science Foundation of China(Grant Nos.30770148,30990241,30530050,39770046 and 41072022)
文摘Charcoals collected from the middle-late Pliocene sediments of the Taigu Basin,Shanxi Province,China,have been identified as Ulmus sp.(Ulmaceae),Prunus sp.,Maloidoxylon sp.(Rosaceae),and Maclura sp.(Moraceae).These taxa,along with the previously known fossils,indicate the occurrence of temperate climate and local wildfire at that time.Charcoals of trees and/or shrubs and the morphological changes of these charcoals demonstrate that crown fires and surface fires occurred in the Taigu Basin during the middle-late Pliocene.
