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It is well-known that the presence of serial correlation may result in an inefficient or even biased estimation in time series analysis. In this paper, we consider testing serial correlation in a general d-factor model when the model errors follow the GARCH process, which is frequently used in modeling financial data. Two empirical likelihood-based testing statistics are suggested as a way to deal with problems that might come up with infinite variance. Both statistics are shown to be chi-squared distributed asymptotically under mild conditions. Simulations confirm the excellent finite-sample performance of both tests. Finally, to emphasize the importance of using our tests, we explore the impact of the exchange rate on the stock return using both monthly and daily data from eight countries.

Based on the phytoplankton community matrices in the Ashi River Basin (ASRB), Harbin city, we developed an evaluation method using the phytoplankton index of biotic integrity (P-IBI) to evaluate ecological health while investigating the response of P-IBI to anthropogenic activities. We compared the effectiveness of P-IBI with that of the water quality index (WQI) in assessing ecological health. Between April and October 2019, phytoplankton and water samples were collected at 17 sampling sites in the ASRB on a seasonal basis. Our results showed that seven phyla were identified, comprising 137 phytoplankton species. From a pool of 35 candidate indices, five critical ecological indices (Shannon–Wiener index, total biomass, percentage of motile diatoms, percentage of stipitate diatom, and diatom quotient) were selected to evaluate the biological integrity of phytoplankton in the ASRB. The ecological status of the ASRB as measured by the P-IBI and WQI exhibited a similar spatial pattern. It showed a spatial decline in ecological status in accordance with the flow of the river. These results highlighted that P-IBI was a reliable tool to indicate the interaction between habitat conditions and environmental factors in the ASRB. Our findings contribute to the ecological monitoring and protection of rivers impacted by anthropogenic pollution.

Woodwardia japonica is a kind of great potential edible and medicinal fern. In a previous study, it was found that flavonoid and antioxidant activity of W. japonica from different sites were different. However, the cause of the differences has still been unclear, which has restricted the utilization of W. japonica. In this paper, flavonoid and antioxidant activity of W. japonica from nine different regions were determined with the method of a colorimetric assay with UV-VIS spectrophotometry and HPLC-ESI-TOF-MS, and the effects of climate factors on flavonoids and antioxidant activities were evaluated by mathematical modeling and statistical methods. The results showed: (1) total flavonoid content (TFC) of W. japonica from Wuyi Mountain (Jiangxi) was the highest, which might be related to the low temperature; (2) the differences of antioxidant activities of W. japonica might be related to precipitation; (3) five flavonols, two flavones and one isoflavone were tentatively identified in W. japonica; (4) flavonol and isoflavone might be affected by sunshine duration, and flavones were probably related to temperature. In conclusion, the effects of climate factors on flavonoids and antioxidants are significant, which would provide an important basis for further exploring the mechanism of climate affecting secondary metabolites.

Achnanthidium tibeticum Y. Liu & J.P. Kociolek sp. nov. Figures 1���32 Type:����� CHINA. Tibet: Medog County, Yarang Village, Streams, 95��28���22.8 E, 29��29���97.0 N,19 June, 2019. (holotype HANU! Slide no. THTYJZL12, College of Life Science and Technology, Harbin Normal University, Harbin, China. Figs 1 & 2 are of the holotype specimen). Isotype: Material no. YJZL12-12, slide no. YJZL12-12 #. Cleaned material stored in Key laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China. Description:����� LM (Figs 1���14): Raphe valve slightly convex, rapheless valve slightly concave. Valves linear to elliptic, with apices rounded. Length 7.9���3.6 ��m, width 2.9���3.9 ��m (n=25). Axial area narrow and linear. On the raphe valve, striae become coarser in the middle of valve, central area is inconspicuous. On the rapheless valves, central area is absent. On the raphe valves, striae slightly radiate in the center, becoming radiate towards the ends; 9���12 per 10 ��m in center of raphe valve, denser near the ends at 18���20 per 10 ��m. On the rapheless valve, striae nearly parallel in the center and become slightly radiate towards the ends; 12���15 per 10 ��m. SEM: Raphe valve (Figs 15���26): Externally, raphe on the valve face never extends onto the mantle, straight, distal raphe ends?-shaped, curved to the same direction (Figs 15���17, 20), proximal raphe ends slightly expanded, teardrop-shaped. Striae uniseriate, areolae almost round, with varying sizes. One row of slit-like areolae present in the mantle. Internally, raphe straight, distal raphe ends terminate in small helictoglossae, proximal raphe ends curved to the opposite directions. Areolae are occluded by fine hymenate structures. Rapheless valve (Figs 27���32): Externally, axial area narrow and linear; central area absent, areolae almost round. One row of slit-like areolae present on the mantle. Internally, sternum slightly raised on the apices, areolae structure similar to the raphe valve, with finely structured occlusions. Etymology:����� Named for the province of the type locality., Published as part of Ge, Danyang, Zhang, Simeng, Liu, Hongyan, Liu, Yan, Kociolek, Patrick John, Zhu, Huan, Liu, Guoxiang & Fan, Yawen, 2022, One new species of Achnanthidium K��tzing (Bacillariophyta, Achnanthidiaceae) from Tibet, China, pp. 268-280 in Phytotaxa 538 (4) on pages 271-275, DOI: 10.11646/phytotaxa.538.4.1, http://zenodo.org/record/6340368

2011-2012年间对扎龙国家级自然保护区的藻类标本进行采集及观察鉴定.研究发现，该区域鼓藻类植物生物多样性较高，共观察到90个分类单位.研究过程中发现宽带鼓藻属的一个新种——Pleurotaenium parvulum Li，Fan & Wei.该物种特征为植物体单细胞，细胞小型，长圆柱形；半细胞顶端平截，其缘边横断面可见5个小结节；细胞壁平滑或具点纹；半细胞具两个轴生星状的色素体，每个色素体具1个蛋白核.本文比较了该物种与其相近种类之间的差异.

Samples were collected from Great Xing′an Mountains during 2004 to 2007.Six taxa of Aulonoraphidinales were identified as the newly recorded species in China.They are:Hantzschia calcifuga Reichardt & Lange-Bertalot, Nitzschia homburgiensis Lange-Bertalot, Nitzschia nana Grunow, Nitzschia terrestris (Petersen) Hustedt, Stenopterobia anceps (Lewis) Brébisson, Stenopterobia delicatissima (Lewis) Brébisson ex Van Heurck.The morphological features and habitat distribute pattern of these taxa were reported in this paper.

This paper is about the structure of phytoplankton communities in the autumn of 2010 in Anxing Wetland,Heilongjiang Province,China.The abundance of phytoplankton communities,cell density and dominant species were analyzed.In total,146 taxa were identified from nine sampling sites.The 146 taxa included 6 divisions,8 classes,12 orders,25 families,45 genera,128 species,17 varieties and 1 form.Chlorophyta were dominant and accounted for 39.7% of the total phytoplankton,while Euglenophyta and Bacillariophyta accounted for 30.8% and 21.9%,respectively.The abundance of phytoplankton was 181.4×106 cells/L.Dominance analysis showed that there were more than three dominant species at each sampling site,including Trachelomonas granulosa Playf.,Cyclotella meneghiniana Kutz.and Trachelomonas granulosa var.crenulatocollis(Szab.)Hub.-Pest..Cluster and non-metric Multi Dimensional Scaling analysis showed that nine sampling sites were divided into five groups and the composition of phytoplankton communities were significant different spatially when the similarity of the phytoplankton community reached to 60%.That was related to different ecological characteristics of each site.Canonical Correspondence Analysis showed that dominant specie change was mainly influenced by temperature and pH.In addition,a large number of β-mesosaprobic zone indicators and lower diversity index were monitored in Anxing Wetland,suggesting that the water quality from the wetlands might have been polluted.

Monthly algae samples in Hulanhe Wetland,Heilongjiang Province,were collected from May to October,2009.A total of 158 taxa,belonging to 7 phyla,8 classes,14 orders,23 families,50 genera,148 species and 10 varieties,were identified.The abundance of algae ranged from 469.55×105-847.35×105cells/L.They were predominantly Bacillariophyta and Chlorophyta.The composition and biomass of the algae varied with the studying periods.Most of the algae were found in the site II.While the biomass in sites I and V was greater than that of other sites.Results showed that most taxa were common species and several indicator species for eutrophication and pollution were also found.According to the assessments using saprobic indicator,Shannon-Wiener diversity index and Pielou evenness index,the water in Hulanhe Wetland was of different degrees of pollution.

The algal community was studied in Heihe channel in Heilongjiang River during May to October of 2006-2007, according to the taxon and relations between algal assemblage structures and environmental variables based on data from six monitor stations, and was analyzed by use of Canonical correspondence analysis. It revealed that biology oxygen demand, total phosphorus, water temperature and chemical oxygen demand from 7 water environmental variables are significant fractions of the distribution and variation of algal community. CCA result indicates that, the algal community and space distribution are correlated with environmental variables, the variety of the algal community may become a useful monitor for river environments.

The species of Epithemia ocellata (Ehr.) Kutz. from Northeastern China were observed by scanning electron microscopy (SEM). The studies on silica valve formation in different stages were made. At the early stage, a Y-shaped raphe sternum was found. Areolae were made from virgae and vimines. In immature valves, the canal formation before the raphe fissure is visible. The raphe system, virgae and vimines (areolae) might be the early siliceous elements of the valve during morphogenesis. The formations of virgae and vimines are similar to that of Gephyria media W. Arnott. Rows of silica papillae formed gradually on the face of the valve. After the areolae were covered with silica and form rows of papillae, the outer valve surface could become mature. Details of the internal costae were observed in mature valves.

Liu, Yan, Kociolek, John Patrick, Wang, Quanxi, Tan, Xiang, Fan, Yawen (2014): Two new species of monoraphid diatom (Bacillariophyceae) from South of China. Phytotaxa 188 (1): 31-37, DOI: 10.11646/phytotaxa.188.1.4, URL: http://dx.doi.org/10.11646/phytotaxa.188.1.4

The authors discribed a new polystigmate combination,Gomphonema turris Ehr. var.okamurae (Skv.) Fan et Bao. comb. nov., and two new varieties,Gomphonema turris Ehr. var.latum Fan et Wang. var. nov. andGomphonema acuminatum var.obtusum Fan et Bao, var. nov., that were distinguished by frustule morphology under LM. The samples were collected from freshwater of Heilongjiang Province, China.

Ge, Lei, Liu, Yan, Kociolek, J. Patrick, Fan, Yawen (2014): A new species of Gomphonema (Bacillariophyta) from Xingkai Lake, China. Phytotaxa 175 (5): 249-255, DOI: 10.11646/phytotaxa.175.5.2, URL: http://dx.doi.org/10.11646/phytotaxa.175.5.2