Asexual Reproduction of Aurelia coerulea Polyps in situ on Settling Plates in Jiaozhou Bay,China

Jellyfish blooms are increasingly prevalent coastal phenomena,with Aurelia coerulea being a significant contributor.The complex life history of jellyfish,featuring a sessile polyp stage,is a key factor in bloom formation,yet it is challenging to study in the field.This study aimed to describe the asexual reproduction of A.coerulea polyps in Jiaozhou Bay,China,and to assess their ability to form sedentary colonies and their relationship with environmental factors.Using settling plates,we observed polyps in situ and documented three asexual reproduction modes:budding,strobilation,and podocyst formation.Environmental parameters including temperature,salinity,dissolved oxygen(DO),chlorophyll a(Chl a),and the biomass of phytoplankton and zooplankton were monitored.Budding was the predominant reproductive method,featuring stolon budding in autumn and direct budding during the winter and spring seasons.Strobilation took place in the colder months,releasing ephyrae between April and May.Polyp abundance was positively correlated with seawater temperature and negatively correlated with DO concentration.Polyps at 1.0 m depth showed higher survivorship and proliferation over 8 months,whereas those at 2.0 m depth experienced a steady decline and died within 4 months.The study enhances our understanding of the life cycle and asexual reproduction strategies of A.coerulea polyps in the field,with implications for predicting and managing jellyfish blooms.The findings underscore the importance of temperature and DO in polyp survival and suggest that initial polyp population proliferation is crucial for long-term survival.

Geochronology and Geochemistry of the Permian Granitoids from the Alxa Area,Inner Mongolia,China:Constrains on the Permian Evolution of the Central Asian Orogenic Belt

We report new SHRIMP zircon U-Pb ages,zircon Lu-Hf isotopic and whole rock geochemical data from Permian granitoids located in the Alxa area of Inner Mongolia,China.In combination with published geochronological and geochemical data,the granitoids in the region can be divided into two age groups:ca.285 Ma and ca.269 Ma.The granitoids of the first group are mainly composed of calc-alkaline to high-K calc-alkaline,weakly peraluminous Ⅰ-type granodiorites with ε_(Hf)(t)values of-19.6 to-4.3,which demonstrates evidence of crustal reworking;the granitoids of the second group,however,mainly consist of A-type granites that are high-K calc-alkaline to shoshonite,metaluminous to weakly peraluminous,and have high 10,000×Ga/Al ratios(2.59-3.12)and ε_(Hf)(t)values ranging from-11.3 to-2.7,all of which demonstrates a mixed crust-mantle source.We interpret the granitoids of the first group to have formed during the subduction of Central Asian oceanic crust and the second group to have formed by the asthenospheric upwelling caused by the formation of slab windows during late ocean ridge subduction.

Species diversity of Hygrophorus(Hygrophoraceae,Agaricales)in Shanxi Province and description of Hygrophorus brunneodiscoides sp.nov.

[Background]Hygrophorus,belonging to Basidiomycota,Agaricomycetes,Agaricales,Hygrophoraceae,is widely distributed all around the world.[Objective]To investigate the species of Hygrophorus and enrich the knowledge about the species diversity of this genus in Shanxi Province.[Methods]We collected fungal specimens,observed and characterized their morphology.After DNA extraction,the internal transcribed spacer(ITS)was sequenced.Phylogenetic trees were constructed based on the maximum likelihood method and Bayesian inference.[Results]Eleven species of Hygrophorus were identified based on the morphological and molecular evidence,including ten known species and a new species.This article described the macroscopic and microscopic morphological characteristics of the new species Hygrophorus brunneodiscoides in detail.The basidiocarp photos of ten known species and a key to the species of Hygrophorus in Shanxi Province were provided.[Conclusion]We identified a new species,H.brunneodiscoides,in China,confirmed 11 species of Hygrophorus in Shanxi Province,and briefed their geographical distribution and associations with hosts according to the field observation.

盐分介导下芦苇对不同邻体植物的表型可塑性响应

随着滨海湿地生态系统盐胁迫增加,群落中的植物同时受到盐胁迫和植物相互作用的影响。非生物因素干扰植物之间竞争和促进效应的稳定,使植物产生复杂的表型可塑性响应。探讨不同的邻体物种及对性状可塑性的影响将会扩展胁迫梯度假说,深入理解盐沼湿地的物种分布特征。本研究开展温室控制实验,探究盐胁迫下(0和10 g/L)芦苇(Phragmites australis)对3种功能类型7种邻体植物(同种植物、禾草类植物和杂草类植物)的表型可塑性响应。实验测量了株高、基径、密度、叶厚度、比叶面积、总生物量和各部分生物量等性状,计算了邻体效应指数(基于生物量)和相对表型可塑性指数。结果表明,盐分显著降低了芦苇的生物量、株高、密度和基径。邻体植物的功能类型显著影响芦苇的生长性状。盐分为0 g/L时,禾草类植物对芦苇形成负的竞争效应,但在10 g/L盐分下,这种负效应转变为正的促进作用。芦苇的生长性状对盐分和竞争具有可塑性反应,如增加地下生物量以获得更多的水分和资源,可塑性指数在盐分条件下比竞争条件下更高。总之,植物-植物相互作用对胁迫的响应随植物功能类型和性状可塑性而异。