Through the investigations of sample belt transects and sample quadrats, the variation characteristics of the disturbed ecosystem by highway engineering in the permafrost region along the Qinghai-Tibet highway line we...Through the investigations of sample belt transects and sample quadrats, the variation characteristics of the disturbed ecosystem by highway engineering in the permafrost region along the Qinghai-Tibet highway line were studied from the ecological elements such as permafrost eco-system, community type,biodiversity and biological produc-tivity and biological habitat conditions including soil envi-ronmental conditions and permafrost environmental condi-tions. The results show that in the sense of biology the resto-ration of high-cold steppe ecosystem was much better than that of high-cold meadow ecosystem after nearly 5 a of natu-ral reconversion.This is mainly manifested in several resspects:The dominant plant species of the high-cold steppe have occurred or even held a predominant position; local zonal biodiversity and population abundance have reached or even exceeded the level of the undisturbed natural steppe system.Viewed from soil environment change, organic matter content in the disturbed high-cold steppe on an average de-creased by 61.5% and total N content decreased by 52.51%,but the nutrient regime of surface soil layer in most of the region corresponded to that of main grassland soil types in the arid region,which is favourable to the growth of cold-resistant species. The mean nutrient contents of the dis-turbed high-cold meadow soil(Gelic cambosols)were higher than those of natural cryic aridsols. The maintenance of the integrity of meadow soil structure is crucial to the restoration of high-cold meadow ecosystem.However,the distribution and maintenance of high-cold meadow ecosystem were closely related to the permafrost environment,the restoration degree of the disturbed high-cold steppe ecosystem did not show an obvious restrictive relation with permafrost environ-ment.Once the permafrost environment was destroyed by the engineering activities,the high-cold meadow ecosystem was very difficult to rehabilitate. From the comparison of the variation laws of the ecosystem along the Qinghai-Tibet highway l展开更多
In August 2003, we investigated spatial pattern in soil carbon and nutrients in the Alpine tundra of Changbai Moun-tain, Jilin Province, China. The analytical results showed that the soil C concentrations at different...In August 2003, we investigated spatial pattern in soil carbon and nutrients in the Alpine tundra of Changbai Moun-tain, Jilin Province, China. The analytical results showed that the soil C concentrations at different depths were significantly (p<0.05) higher in Meadow alpine tundra vegetation than that in other vegetation types; the soil C (including inorganic carbon) concentrations at layer below 10 cm are significantly (p<0.05) higher than at layer of 1020 cm among the different vegetation types; the spatial distribution of soil N concentration at top surface of 0-10 cm depth was similar to that at 1020 cm; the soil P concentrations at different depths were significantly (p<0.05) lower at Lithic alpine tundra vegetation than that at other vegetation types; soil K concentration was significantly (p<0.05) higher in Felsenmeer alpine tundra vegetation and Lithic alpine tundra vegetation than that in Typical alpine tundra, Meadow alpine tundra, and Swamp alpine tundra vegetations.. However, the soil K had not significant change at different soil depths of each vegetation type. Soil S concentration was dramatically higher in Meadow alpine tundra vegetation than that in other vegetation types. For each vegetation type, the ratios of C: N, C: P, C: K and C: S generally decreased with soil depth. The ratio of C: N was significantly higher at 010 cm than that at 1020 cm for all vegetation types except at the top layer of the Swamp alpine tundra vegetation. Our study showed that soil C and nutrients storage were significantly spatial heterogeneity.展开更多
文摘Through the investigations of sample belt transects and sample quadrats, the variation characteristics of the disturbed ecosystem by highway engineering in the permafrost region along the Qinghai-Tibet highway line were studied from the ecological elements such as permafrost eco-system, community type,biodiversity and biological produc-tivity and biological habitat conditions including soil envi-ronmental conditions and permafrost environmental condi-tions. The results show that in the sense of biology the resto-ration of high-cold steppe ecosystem was much better than that of high-cold meadow ecosystem after nearly 5 a of natu-ral reconversion.This is mainly manifested in several resspects:The dominant plant species of the high-cold steppe have occurred or even held a predominant position; local zonal biodiversity and population abundance have reached or even exceeded the level of the undisturbed natural steppe system.Viewed from soil environment change, organic matter content in the disturbed high-cold steppe on an average de-creased by 61.5% and total N content decreased by 52.51%,but the nutrient regime of surface soil layer in most of the region corresponded to that of main grassland soil types in the arid region,which is favourable to the growth of cold-resistant species. The mean nutrient contents of the dis-turbed high-cold meadow soil(Gelic cambosols)were higher than those of natural cryic aridsols. The maintenance of the integrity of meadow soil structure is crucial to the restoration of high-cold meadow ecosystem.However,the distribution and maintenance of high-cold meadow ecosystem were closely related to the permafrost environment,the restoration degree of the disturbed high-cold steppe ecosystem did not show an obvious restrictive relation with permafrost environ-ment.Once the permafrost environment was destroyed by the engineering activities,the high-cold meadow ecosystem was very difficult to rehabilitate. From the comparison of the variation laws of the ecosystem along the Qinghai-Tibet highway l
基金This research was supported by National Natural Science Foundation of China (40173033) and Important Direction Project of Knowl-edge Innovation of Chinese Academy of Sciences (KZCX3-SW-423).
文摘In August 2003, we investigated spatial pattern in soil carbon and nutrients in the Alpine tundra of Changbai Moun-tain, Jilin Province, China. The analytical results showed that the soil C concentrations at different depths were significantly (p<0.05) higher in Meadow alpine tundra vegetation than that in other vegetation types; the soil C (including inorganic carbon) concentrations at layer below 10 cm are significantly (p<0.05) higher than at layer of 1020 cm among the different vegetation types; the spatial distribution of soil N concentration at top surface of 0-10 cm depth was similar to that at 1020 cm; the soil P concentrations at different depths were significantly (p<0.05) lower at Lithic alpine tundra vegetation than that at other vegetation types; soil K concentration was significantly (p<0.05) higher in Felsenmeer alpine tundra vegetation and Lithic alpine tundra vegetation than that in Typical alpine tundra, Meadow alpine tundra, and Swamp alpine tundra vegetations.. However, the soil K had not significant change at different soil depths of each vegetation type. Soil S concentration was dramatically higher in Meadow alpine tundra vegetation than that in other vegetation types. For each vegetation type, the ratios of C: N, C: P, C: K and C: S generally decreased with soil depth. The ratio of C: N was significantly higher at 010 cm than that at 1020 cm for all vegetation types except at the top layer of the Swamp alpine tundra vegetation. Our study showed that soil C and nutrients storage were significantly spatial heterogeneity.
