The effects of ammonium on the population growth of the marine ciliate, Euplotes vannus, were examined using ecotoxicological method, h is showed that ammonium exerts inhibitory effects on the growth of the ciliate po...The effects of ammonium on the population growth of the marine ciliate, Euplotes vannus, were examined using ecotoxicological method, h is showed that ammonium exerts inhibitory effects on the growth of the ciliate populations in a concentration-dependent way. Statistical analvsis reveals that the population growth dynamics exposed to ammoniunt-N concentration over 100mg/L are significantly different from that in the control at P 〈 0.05 level. Linear regression determined that the 24h, 36h, 48h, 60h, 72h and 84h IC50 values of ammonium-N are 19.68, 201.51, 167.49, 47.86, 50.43 and 43.11 concentration over 100mg/L, respectively （ P 〈 0.05; pH 8.2; salinity 28 ppt; temperature, 25℃ ）. The results indicate that the tolerance to ammonium in E. vannus is considerably higher than that of the larvae or juveniles of some metozoa, such as cuhured prawns and oysters. Therefore, it is believed that the high tolerance to ammonium is necessary for eiliated protozoa to play positive roles in maintaining and improving water quality in marine ecosystems, especially in the intensive aquacuhure waters with high-level ammonium. In addition, the correlation between /C50 values and exposure time was discussed.展开更多
This work is devoted to developing of the ecologically safe technology of chickpea cultivation by using microbial biopreparations, based on the effective heterotrophic （nodulating, growth-promoting and phosphate mobi...This work is devoted to developing of the ecologically safe technology of chickpea cultivation by using microbial biopreparations, based on the effective heterotrophic （nodulating, growth-promoting and phosphate mobilizing bacteria, and microorganisms-antagonists of the phytopathogenes） and phototrophic microorganisms （cyanobacteria）. These preparations were used for pre-sowing treatment of seeds and for treatment of the plants in the vegetation period for optimization of symbiotic nitrogen fixation and growing of ecologically safe production （without application of mineral fertilizers） in the steppe non-irrigated areas of Ukraine.展开更多
Aboveground biomass in grasslands of the Qinghai-Tibet Plateau has displayed an overall increasing trend during 2003–2016, which is profoundly influenced by climate change. However, the responses of different biomes ...Aboveground biomass in grasslands of the Qinghai-Tibet Plateau has displayed an overall increasing trend during 2003–2016, which is profoundly influenced by climate change. However, the responses of different biomes show large discrepancies, in both size and magnitude. By applying partial least squares regression, we calculated the correlation between peak aboveground biomass and mean monthly temperature and monthly total precipitation in the preceding 12 months for three different grassland types(alpine steppe, alpine meadow, and temperate steppe) on the central and eastern Qinghai-Tibet Plateau. The results showed that mean temperature in most preceding months was positively correlated with peak aboveground biomass of alpine meadow and alpine steppe, while mean temperature in the preceding October and February to June was significantly negatively correlated with peak aboveground biomass of temperate steppe. Precipitation in all months had a promoting effect on biomass of alpine meadow, but its correlations with biomass of alpine steppe and temperate steppe were inconsistent. It is worth noting that, in a warmer, wetter climate, peak aboveground biomass of alpine meadow would increase more than that of alpine steppe, while that of temperate steppe would decrease significantly, providing support for the hypothesis of conservative growth strategies by vegetation in stressed ecosystems.展开更多
基金国家高技术研究发展计划(863计划)，the National Natural Science Foundation of China
文摘The effects of ammonium on the population growth of the marine ciliate, Euplotes vannus, were examined using ecotoxicological method, h is showed that ammonium exerts inhibitory effects on the growth of the ciliate populations in a concentration-dependent way. Statistical analvsis reveals that the population growth dynamics exposed to ammoniunt-N concentration over 100mg/L are significantly different from that in the control at P 〈 0.05 level. Linear regression determined that the 24h, 36h, 48h, 60h, 72h and 84h IC50 values of ammonium-N are 19.68, 201.51, 167.49, 47.86, 50.43 and 43.11 concentration over 100mg/L, respectively （ P 〈 0.05; pH 8.2; salinity 28 ppt; temperature, 25℃ ）. The results indicate that the tolerance to ammonium in E. vannus is considerably higher than that of the larvae or juveniles of some metozoa, such as cuhured prawns and oysters. Therefore, it is believed that the high tolerance to ammonium is necessary for eiliated protozoa to play positive roles in maintaining and improving water quality in marine ecosystems, especially in the intensive aquacuhure waters with high-level ammonium. In addition, the correlation between /C50 values and exposure time was discussed.
文摘This work is devoted to developing of the ecologically safe technology of chickpea cultivation by using microbial biopreparations, based on the effective heterotrophic （nodulating, growth-promoting and phosphate mobilizing bacteria, and microorganisms-antagonists of the phytopathogenes） and phototrophic microorganisms （cyanobacteria）. These preparations were used for pre-sowing treatment of seeds and for treatment of the plants in the vegetation period for optimization of symbiotic nitrogen fixation and growing of ecologically safe production （without application of mineral fertilizers） in the steppe non-irrigated areas of Ukraine.
基金National Key R&D Program of China,No.2018YFA0606102National Natural Science Foundation of China,No.41771056National Key Technology Support Program,No.2012BAH31B02
文摘Aboveground biomass in grasslands of the Qinghai-Tibet Plateau has displayed an overall increasing trend during 2003–2016, which is profoundly influenced by climate change. However, the responses of different biomes show large discrepancies, in both size and magnitude. By applying partial least squares regression, we calculated the correlation between peak aboveground biomass and mean monthly temperature and monthly total precipitation in the preceding 12 months for three different grassland types(alpine steppe, alpine meadow, and temperate steppe) on the central and eastern Qinghai-Tibet Plateau. The results showed that mean temperature in most preceding months was positively correlated with peak aboveground biomass of alpine meadow and alpine steppe, while mean temperature in the preceding October and February to June was significantly negatively correlated with peak aboveground biomass of temperate steppe. Precipitation in all months had a promoting effect on biomass of alpine meadow, but its correlations with biomass of alpine steppe and temperate steppe were inconsistent. It is worth noting that, in a warmer, wetter climate, peak aboveground biomass of alpine meadow would increase more than that of alpine steppe, while that of temperate steppe would decrease significantly, providing support for the hypothesis of conservative growth strategies by vegetation in stressed ecosystems.
