Finally, we prospected the 13C and 15N isotopes application in researches on soil organic carbon and soil respiration in the alpine meadow, transitions of vegetation type, and climate change, soil N2O trace, exploration of vegetation degradation, identification of the origin of Tibetan medicine and animal food, etc. 13C and 15N isotopes could be widely used and play important roles in researches on the alpine ecosystems.Carbon and nitrogen stable isotope analysis was carried out on pelagic fishery organisms caught in light traps and falling nets in the central and western South China Sea in the spring of 2018. The stable isotope values of the sampled individuals were used to elucidate the isotopic variations for the pelagic fishery organisms, to classify species into trophic functional groups, and to compare the differences of trophic structure among the classified trophic functional groups. The results showed that among 23 fishery species the mean δ13C value of Coryphaena hippurus was the lowest (-17.58‰±0.21‰), and that of Grammistes sexlineatus was the highest (-19.86‰±0.33‰). The mean δ15N values ranged from 8.31‰ in Psenes cyanophrys to (12.46±0.74)‰ in Chirocentrus dorab. The continuous trophic spectrum indicated that the trophic level (TL) for the sampled pela-gic fishery organisms ranged from 3.01 to 4.23, of which 19 species (83% of the total) fell between TL 3.0 and 4.0. The 23 species of fishery organisms were classified into three trophic functional groups, i.e., plankton feeding functional group (PFFG), nekton feeding functional group (NFFG), and mixed feeding functional group (MFFG). The analysis of standard ellipse area (SEA) showed that the PFFG occupied the largest trophic niche width (SEA=1.56‰2), followed by the MFFG (SEA=0.99‰2) and NFFG (SEA=0.31‰2). The MFFG overlapped with PFFG and NFFG in the trophic niche, with a relative percentage of 17% and 26%, respectively. There was no overlap between PFFG and NFFG.To examine the suitability of Myzus persicae, Lipaphis erysimi, Semiaphis heraclei and Aphis gossypii to propagation of Harmonia axyridis population, we studied the development and reproduction of this ladybird by constructing two-sex life table in the laboratory with those four aphid species as diet. The results showed that the immature duration of H. axyridis decreased in an order of L. erysimi (18.18 d), A. gossypii (17.48 d), S. heraclei (16.23 d), and M. persicae (15.77 d). The survival rates of preadult period were S. heraclei (88.3%), M. persicae (86.7%), L. ery-simi (55.0%), and A. gossypii (55.0%). The fecundity of those species were S. heraclei (1750.5), M. persicae (1441.5), A. gossypii (1006.3), and L. erysimi (965.2). The longevity of adult ladybird were S. heraclei (78.8 d), M. persicae (63.1 d), A. gossypii (54.3 d), and L. erysimi (48.4 d). The intrinsic rate of increase (rm) of H. axyridis population decreased in an order of M. persicae (0.19), S. heraclei (0.18), L. erysimi (0.14), and A. gossypii (0.14). The net reproduction rates (R0) were S. heraclei (895.83), M. persicae (600.62), L. erysimi (273.47), and A. gossypii (268.33). Among those four aphid species, S. heraclei and M. persicae were more suitable for the propagation of H. axyridis population.Some fungi engage symbiosis with bacteria, which can effectively promote the metabolism and growth of fungi. The diversity and community structure of bacteria can reflect the growth and substrate utilization of fungi. In this study, we analyzed the effects of different sawdust dosages on the community structure and diversity of bacteria associated with the hyphae of Pleurotus eryngii using high-throughput sequencing technology (HST) based on PCR-amplified 16S rRNA V3-V4 fragments. The results showed that the high-quality sequences from five groups of mycelia samples were clustered into 25 phyla, 52 classes, 114 orders, 199 families, and 406 genera. Proteobacteria (35.0%-85.9%) and Firmicutes (6.5%-38.4%) were the most abundant bacterial phyla, while Acinetobacter (14.8%-71.6%) and Pseudomonas (1.7%-22.3%) were the dominant symbiotic genera. Compared with the mycelia grown on the complete culture medium, sawdust addition could increase the diversity of bacteria coexisting with P. eryngii mycelia, and change the community structure of 10 dominant phyla and 9 dominant genera. P. eryngii cultivated in substrate containing 5 g sawdust had the fastest mycelium growth rate, thick mycelia, and neatly edges. Furthermore, judging from the abundance and diversity, Pseudomonas and Lactobacillus became the dominant genera, which were positively correlated with the mycelia growth vigour. Sawdust, as an important carbon source, could affect the growth and development of P. eryngii and the community structure and diversity of bacteria coexisting with mycelia. This study would lay a theoretical foundation for exploring the molecular mechanism of sawdust and mycelium symbiosis affecting the growth and development of P. eryngii.We constructed consortia of Chlorella salina and Bacillus subtilis with various alga-bacterium ratios (10, 11, 12, 13, 14). After being treated with arsenate [As(Ⅴ)] for 7 d, we measured the growth, As accumulation, adsorption and absorption, and As speciation transformation of consortia. Results showed that the chlorophyll content, dry weight, and specific growth rate of the symbiont increased significantly with increasing B. subtilis ratio after the As(Ⅴ) treatment, being 1.81 mg·L-1, 125.0 mg, and 0.28 mg·L-1·d-1 under the condition of the alga-bacterium ratio being 1∶4 and As(Ⅴ) being 750 μg·L-1, respectively.  https://www.selleckchem.com/products/ly3522348.html  The accumulation and absorption of As by the consortia decreased with the bacterial proportion increasing from 10 to 14. As accumulation changed with the As concentration, with a dominance of absorption under 75-150 μg·L-1 As(Ⅴ) and a dominance of adsorption under 300-750 μg·L-1As(V). There were As(Ⅴ) and As(Ⅲ) in the consortia. When the proportion of bacteria increased, the rate of As(Ⅴ) reduction enhanced (up to 12.6%). Our results indicated that the increases of B. subtilis improved As(Ⅴ) tolerance and reduction, but decreased the As(Ⅴ) accumulation by the symbiont.