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Incorporating topographic factors in nonlinear mixed-effects models for aboveground biomass of natural Simao pine in Yunnan,China

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Journal of Forestry Research 2016年第1期27卷 119-131页

作者： Guanglong Ou Junfeng Wang Hui Xu Keyi Chen Haimei Zheng Bo Zhang Xuelian Sun Tingting Xu Yifa Xiao Key Laboratory of biodiversity conservation in Southwest China of State Forest Administration Southwest Forestry University

A total of 128 Simao pine trees （Pinus kesiya var. langbianensis） from three regions of Pu＇er City, Yunnan Province, People＇s Republic of China, were destructively sampled to obtain tree aboveground biomass （AGB）. Tree variables such as diameter at breast height and total height, and topographical factors such as altitude, aspect of slope, and degree of slope were recorded. We considered the region and site quality classes as the ran- dom-effects, and the topographic variables as the fixed- effects. We fitted a total of eight models as follows： least- squares nonlinear models （BM）, least-squares nonlinear models with the topographic factors （BMT）, nonlinear mixed-effects models with region as single random-effects （NLME-RE）, nonlinear mixed-effects models with site as single random-effects （NLME-SE）, nonlinear mixed-ef- fects models with the two-level nested region and site random-effects （TLNLME）, NLME-RE with the fixed-ef- fects of topographic factors （NLMET-RE）, NLME-SE with the fixed-effects of topographic factors （NLMET-SE）, and TLNLME with the fixed-effects of topographic factors （TLNLMET）. The eight models were compared by modelfitting and prediction statistics. The results showed： model fitting was improved by considering random-effects of region or site, or both. The models with the fixed-effects of topographic factors had better model fitting. According to AIC and BIC, the model fitting was ranked as TLNLME 〉 NLMET-RE 〉 NLME-RE.〉 NLMET-SE 〉 TLNLMET 〉 NLME-SE 〉 BMT 〉 BM. The differences among these models for model prediction were small. The model pre- diction was ranked as TLNLME 〉 NLME-RE 〉 NLME- SE 〉 NLMET-RE 〉 NLMET-SE 〉 TLNLMET 〉 BMT 〉 BM. However, all eight models had relatively high prediction precision （〉90 %）. Thus, the best model should be chosen based on the available data when using the model to predict individual tree AGB.

关键词： Aboveground biomass Mixed-effectsmodels Regional effect Site quality effect Topographicfactors Pinus kesiya var. langbianensis

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Trophic Ecology of Ansonia latidisca at Gunung Penrissen, Sarawak, North-Western Borneo

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Asian Herpetological Research 2021年第2期12卷 250-260页

作者： Jia Jet ONG Indraneil DAS Institute of biodiversity ami Environmental conservation Universiti Malaysia SarawakKota Samamhan 94300SaniwakMalaysiii

Dietary data on Ansonia latidisca, the little known Bornean Rainbow Toad, are presented, through an investigation of a population at Gunung Penrissen, Sarawak, Malaysia(north-western Borneo), at elevations between 1,100–1,229 m asl. Standard sampling techniques, including visual encounter surveys, were employed and individuals encountered stomach-flushed, ma rked, a nd released. The volume of food ingested by adults, apart from large females, did not vary monthly, and there was no significant difference between wet and dry periods, the dominance index between the two periods showing no significant difference, indicating that seasonal variation does not affect the dietary constitution of the species across months. The mean longest prey was recovered from a female in March, during the end of the wet season. Larger individuals did not consume larger prey in the species, although larger females did harvest the largest insects, and as may be expected, had fewer prey items in their stomachs at the time. Males fed on fewer prey items than females, the adult male diet predominantly comprised of members of the Hymenoptera, including formicids(ants), as indicated by percentage frequency of occurrence of 78.69, while for adult females, equivalent figure was 90.70. Coleopterans(beetles) were found secondary in importance(48.8% in females, 5.85% in males), the rest categorized as tertiary. Plant items(including bryophytes) had a high frequency of occurrence(23.3% in females, 4.64% in males). Females examined in the month of July had voluminous stomach contents, and may have eaten more to increase fat reserves for breeding in the upcoming wet season. Since the diet of all size classes consisted of hymenopterans(ants) and coleopterans, the study species is here considered to have a narrow food preference, and consequently, is a dietary specialist.

关键词： Ansonia latidisca Borneo diet ecology Malaysia Sarawak

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Cyprininae phylogeny revealed independent origins of the Tibetan Plateau endemic polyploid cyprinids and their diversifications related to the Neogene uplift of the plateau

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Science China(Life Sciences) 2016年第11期59卷 1149-1165页

作者： Xuzhen Wang Xiaoni Gan Junbing Li Yiyu Chen Shunping He Key Laboratory of Aquatic biodiversity and conservation of the Chinese Academy of Sciences Institute of Hydrobiology Chinese Academy of Sciences

Origin and diversification of the Tibetan polyploid cyprinids(schizothoracins) may help us to explore relationships between diversification of the cyprinids and the Tibetan Plateau uplift. Cyprininae phylogeny was analyzed using mitochondrial and nuclear DNA sequences to trace origins of polyploidy and diversifications of schizothoracins. Ancestral states reconstruction for ploidy levels indicated that the Cyprininae was diploid origin and the schizothoracin clades tetraploid origins. There were two diversification rate shifts along with diversification of the cyprinine fishes in response to the Tibetan uplift. The unusual diversification shifts were located to branches subtending the clades of Tibetan polyploid cyprinids. Our analyses suggested that(i) phylogeny of Cyprininae recovered two independent origins of the Tibetan polyploidy schizothoracins;(ii) diversifications of the schizothoracins were closely related to the Neogene uplift of the Tibetan plateau in the following ways: the relatively ancient Late Oligocene-Middle Miocene adaptive radiation may be associated with the uplift of the southern Tibet and Himalaya; the Middle Miocene-Early Pleistocene lineage-specific diversification broadly coincident with major phase of the Neogene Tibetan uplift; and the most recent Pleistocene diversification shift in Schizothorax closely coincident with the successive Kunlun-Huanghe and Gonghe movements of the Tibetan uplift and the glaciation-induced climate oscillations on the plateau.

关键词： Cyprininae polyploid schizothoracins the Tibetan Plateau diversifications

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Satellite remote sensing reveals overwhelming recovery of forest from disturbances in Asia

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 46-51页

作者： Yiying Zhu Hesong Wang Anzhi Zhang School of Ecology and Nature conservation Beijing Forestry UniversityBeijingChina Key Laboratory of Regional Climate and Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina College of Forestry and Landscape Architecture Xinjiang Agricultural UniversityUrumqiChina

Forest ecosystems play key roles in mitigating human-induced climate change through enhanced carbon uptake;however,frequently occurring climate extremes and human activities have considerably threatened the stability of *** the same time,detailed accounts of disturbances and forest responses are not yet well quantified in *** study employed the Breaks For Additive Seasonal and Trend method-an abrupt-change detection method-to analyze the Enhanced Vegetation Index time series in East Asia,South Asia,and Southeast *** approach allowed us to detect forest disturbance and quantify the resilience after *** showed that 20%of forests experienced disturbance with an increasing trend from 2000 to 2022,and Southeast Asian countries were more severely affected by ***,95%of forests had robust resilience and could recover from disturbance within a few *** resilience of forests suffering from greater magnitude of disturbance tended to be stronger than forests with lower disturbance *** summary,this study investigated the resilience of forests across the low and middle latitudes of Asia over the past two *** authors found that most forests exhibited good resilience after disturbance and about two-thirds had recovered to a better state in *** findings of this study underscore the complex relationship between disturbance and resilience,contributing to comprehension of forest resilience through satellite remote sensing.

关键词： Forest ecosystem Enhanced vegetation index Breaks for additive seasonal and trend method Disturbance Resilience

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Spatiotemporal pattern of bacterioplankton in Donghu Lake

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Chinese Journal of Oceanology and Limnology 2014年第3期32卷 554-564页

作者：张翔颜庆云余育和代梨梨 Key Laboratory of biodiversity and conservation of Aquatic Organisms Institute of HydrobiologyChinese Academy of Sciences University of Chinese Academy of Sciences

Bacterioplankton play key roles in the biogeochemical cycle and in organic contaminant degradation. The species richness and abundance of bacterial subgroups are generally distinct from each other, and this is attributed to their different functions in aquatic ecosystems. The spatiotemporal variations of eight phylogenetic subgroups （Actinobacteria, Bacteroidetes, Cyanobacteria, Firmicutes, Planctomycetes, alpha-, beta-, and gamma-Proteobacteria） derived from Donghu Lake were investigated using PCR-DGGE fingerprinting, to explore their responses to environmental factors. Results indicate that Actinobacteria and beta-Proteobacteria were the two largest bacterial subgroups detected. These two groups and Bacteroidetes showed clear seasonal patterns in composition of the operational taxonomic unit. Results also suggest that the bacterioplankton subgroups in Donghu Lake were significantly correlated with different environmental factors. In brief, the total nitrogen was one of the major factors regulating all the bacterioplankton except for Actinobacteria. However, total phosphorus, another important eutrophication factor, contributed to the two largest bacterial groups （Actinobacteria and beta-Proteobacteria）, as well as to the Cyanobacteria and Firmicutes. Therefore, the responses of bacterioplankton subgroups to environmental factors were different, and this should be attributed to the differences in the fimctions of different groups.

关键词： bacterioplankton PCR-DGGE group-specific primers multivariate analysis

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Thresholds of population persistence for the Yangtze finless porpoise:implications for conservation managements

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Integrative Zoology 2021年第4期16卷 538-547页

作者： Zhigang MEI Mao CHEN Yi HAN Yujiang HAO Jinsong ZHENG Kexiong WANG Ding WANG Key Laboratory of Aquatic biodiversity and conservation of the Chinese Academy of Sciences Institute of HydrobiologyChinese Academy of SciencesWuhanChina

The Yangtze finless porpoise(Neophocaena asiaeorientalis asiaeorientalis),a critically endangered species,is the only cetacean species in the Yangtze River following the functional extinction of baiji(Lipotes vexillifer).To inform conservation actions,two important questions need to be addressed:what is the threshold value of survival rate,and what is the threshold value of population size?We calculate the instantaneous rate of population increase(¯r)for the Yangtze finless porpoise for various combinations of the calf and the non-calf survival *** also test the probability of extinction for different minimum carrying capacities for 100 and 500 years using a stable population *** threshold value of the non-calf survival rate is never lower than 0.869,but current estimates from field data have been far below this *** model based on extinction probability and carrying capacity suggests that the threshold for the population size to persist 100 years required 113 animals,and 472 animals are required to persist 500 ***,we recommend establishing an ex situ reserve network to guarantee the minimum 100-year carrying *** ensure the long-term population viability,we suggest establishing two in situ reserve zones in two lakes and their surrounding reserves to meet a minimum 500-year carrying *** addition,measures to avoid further habitat fragmentation should be priority.

关键词： conservation minimum viable population population viability reserve zones stochasticity

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Seasonal variation of plankton communities influenced by environmental factors in an artificial lake

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Chinese Journal of Oceanology and Limnology 2012年第3期30卷 397-403页

作者：李学梅余育和张堂林冯伟松敖鸿毅颜庆云 Key Laboratory of biodiversity and conservation of Aquatic Organisms Institute of HydrobiologyChinese Academy of Sciences Graduate University of Chinese Academy of Sciences

We evaluated the seasonal variation in plankton community composition in an artificial lake. We conducted microscopic analysis and denaturing gradient gel electrophoresis (DGGE) of PCR-amplified partial 16S rRNAand 18S rRNAgenes to characterize the plankton community. The clustering of unweighted pair group method with arithmetic mean (UPGMA) was then used to investigate the similarity of these plankton communities. DGGE fingerprinting revealed that samples collected at the different sites within a season shared high similarity and were generally grouped together. In contrast, we did not observe any seasonal variation based on microscopic analysis. Redundancy analysis (RDA) of the plankton operational taxonomic units (OTUs) in relation to environmental factors revealed that transparency was negatively correlated with the first axis (R=-0.931), and temperature and total phosphorus (TP) were positively correlated with the first axis (R=0.736 and R=0.660, respectively). In conclusion, plankton communities in the artificial lake exhibited significant seasonal variation. Transparency, phosphorus and temperature appear to be the major factors driving the differences in plankton composition.

关键词： plankton community PCR-DGGE redundancy analysis community diversity artificial lake

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A New Species of the Asian Toad Genus Megophrys sensu lato(Amphibia: Anura: Megophryidae) from Guizhou Province, China

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Asian Herpetological Research 2018年第4期9卷 224-239页

作者： Shize LI Ning XU Jing LIU Jianping JIANG Gang WEI Bin WANG Department of Food Science and Engineering Maotai University CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization and Ecological Restoration biodiversity conservation Key Laboratory of Sichuan Province Chengdu Institute of Biology (CIB) Chinese Academy of Sciences (CAS) biodiversity conservation Key Laboratory Guiyang College

We describe a new species of the genus Megophrys sensu lato from Guizhou Province, China. Molecular phylogenetic analyses based on mitochondrial DNA and nuclear DNA sequences all strongly supported the new species as an independent lineage in Megophrys(Panophrys) clade. The new species is distinguished from its congeners by a combination of the following morphological characteristics:(1) small body size with SVL < 38.8 mm in male and SVL < 42.3 mm in female;(2) vomerine teeth absent;(3) tongue not notched behind;(4) a small horn-like tubercle at the edge of each upper eyelid;(5) tympanum distinctly visible, rounded;(6) two metacarpal tubercles in hand;(7) relative finger lengths: II < I < V < III;(8) toes with rudimentary webbing at bases;(9) heels overlapping when thighs are positioned at right angles to the body;(10) tibiotarsal articulation reaching the level between tympanum to eye when leg stretched forward;(11) an internal single subgular vocal sac in male;(12) in breeding male, the nuptial pads with black nuptial spines on the dorsal bases of the first and second fingers.

关键词： Megophrys sensu lato new species taxonomy phylogenetic analysis Guizhou Province China

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Impact of the Three Gorges Dam on the spawning stock and natural reproduction of Chinese sturgeon in the Changjiang River,China

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Chinese Journal of Oceanology and Limnology 2016年第5期34卷 894-901页

作者：高欣林鹏程黎明政段中华刘焕章 Institute of Hydrobiology Chinese Academy of Sciences Key Laboratory of Aquatic biodiversity and conservation of Chinese Academy of Sciences Chinese Academy of Sciences

Chinese sturgeon(Acipenser sinensis) is the flagship species of the Changjiang *** migration route of this species is blocked by the first dam,the Gezhou Dam,and its reproduction is affected by the Three Gorges Dam(TGD),one of the largest dams in the *** studied the impact of the impoundment of the Three Gorges Reservoir(TGR) since 2003 on the spawning stock and the natural reproduction of the Chinese sturgeon by using our monitoring data from 1997 to *** indicate that TGR impoundment has delayed the first spawning dates of the fish from middle-late October to late November,decreased the amount of spawning activities from twice to only once each year,and significantly reduced egg *** particular,the fish did not demonstrate any spawning activities in ***,TGR impoundment significantly affects the natural reproduction of the fish downstream of the *** spawning stock size of the fish is also predicted to further decrease in the future,which will lead to a risk of population *** regulations must be imposed on decreasing the water temperature to 20℃before mid-October and increasing water discharge downstream of the TGD in October to induce spawning of the Chinese sturgeon.

关键词： Chinese sturgeon Three Gorges Dam spawning activity spawning stock conservation

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Metagenome-based analysis:A promising direction for plankton ecological studies

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Science China(Life Sciences) 2011年第1期54卷 75-81页

作者： YAN QingYun YU YuHe Key Laboratory of biodiversity and conservation of Aquatic Organisms Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China

The plankton community plays an especially important role in the functioning of aquatic ecosystems and also in biogeochemical cycles. Since the beginning of marine research expeditions in the 1870s, an enormous number of planktonic organisms have been described and studied. Plankton investigation has become one of the most important areas of aquatic ecological study, as well as a crucial component of aquatic environmental evaluation. Nonetheless, traditional investigations have mainly focused on morphospecies composition, abundances and dynamics, which primarily depend on morphological identification and counting under microscopes. However, for many species/groups, with few readily observable characteristics, morphological identification and counting have historically been a difficult task. Over the past decades, microbiologists have endeavored to apply and extend molecular techniques to address questions in microbial ecology. These culture-independent studies have generated new insights into microbial ecology. One such strategy, metagenome-based analysis, has also proved to be a powerful tool for plankton research. This mini-review presents a brief history of plankton research using morphological and metagenome-based approaches and the potential applications and further directions of metagenomic analyses in plankton ecological studies are discussed. The use of metagenome-based approaches for plankton ecological study in aquatic ecosystems is encouraged.

关键词： metagenome plankton community morphospecies molecular microbial ecology

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