RESUMEN
This paper established the identification technology of the main root origin of three-year-old spring Panax notoginseng aiming at providing theoretical basis for the protection and traceability of geographical indication products of P. notoginseng. Forty-four samples of three-year-old spring P. notoginseng from Guangxi Baise, Yunnan Wenshan, Yunnan new cultivating regions. The stable isotopic ratios of carbon, nitrogen, hydrogen and oxygen were determined by elemental analysis and stable isotope mass spectrometer. Combined with Duncan multiple comparative analysis, fisher discriminant analysis and sequential discriminant analysis, a origin discriminant model for the main root of three-year-old spring P. notoginseng was established for 3 production areas of P. notoginseng. The geographical climate and environment of three production areas of P. notoginseng are obviously different. From Guangxi Baise-Yunnan Wenshan-Yunnan new cultivating regions, the longitude, average annual temperature and annual precipitation gradually decrease, and the elevation and latitude are increasing. The results of multiple comparative analysis showed that there were significant or very signi-ficant differences in the δ~(13)C,δ~(15)N,δ~2H,δ~(18)O of the main roots of P. notoginseng in three regions. The results of fisher's discriminant analysis and sequential discriminant analysis showed that the correct discriminant rates of the main roots of P. notoginseng for three regions were 80.05%,76.47% and 90.91%, respectively, based on four stable isotope ratios, with an average of 84.09%. Using stable isotope fingerprint and chemometrics method, we can distinguish the origin of the main raw materials and products of P. notoginseng.
Asunto(s)
Panax notoginseng , China , Geografía , Isótopos , Estaciones del AñoRESUMEN
Application of organic amendments is an effective approach for improving soil organic carbon and soil fertility. To investigate the effects of different organic amendments on soil organic carbon and its labile fraction content, a batch of incubation experiments was conducted on the fluvo-aquic soil in Dongting Lake region, Hunan Province. There were six treatments, including soil amended with rice straw, soil amended with Chinese milk vetch, soil amended with bio-organic fertilizer, soil amended with pig manure, and soil amended with rice straw-derived biochar, with unamended soil as control. Each treatment had the same amount of carbon input. After 180 days of incubation, application of organic amendments increased soil labile organic carbon content. Application of bio-organic fertilizer, pig manure and rice straw-derived biochar significantly increased soil organic carbon content by 26.1%, 9.7% and 30.7%, respectively. There was no significant change in soil organic carbon content in rice straw and Chinese milk vetch treatments which were more favourable to the accumulation of soil dissolved organic carbon and microbial biomass carbon. Pig manure was more favourable to the accumulation of soil dissolved organic carbon. Bio-organic fertili-zer could benefit the accumulation of soil microbial biomass carbon and readily oxidizable organic carbon. Rice straw-derived biochar could promote the accumulation of soil microbial biomass carbon and light fraction organic carbon. Compared with rice straw, soil carbon pool management index was increased by 31.8%, 111.6%, 62.2% and 50.7% in Chinese milk vetch, bio-organic fertilizer, pig manure and rice straw-derived biochar treatments, respectively. The performance of bio-organic fertilizer, pig manure, and rice straw biochar was better than rice straw and Chinese milk vetch from the perspective of soil carbon sequestration and soil carbon pool management index.