Geochemistry is a powerful tool to help characterize the tectonic setting of igneous rocks associations.However,when continental mafic dykes and flood basalts are the target most of the proposed geochemical discrimina...Geochemistry is a powerful tool to help characterize the tectonic setting of igneous rocks associations.However,when continental mafic dykes and flood basalts are the target most of the proposed geochemical discrimination diagrams fail to correctly classify them,i.e.many mafic展开更多
Otolith morphology is widely used for fish stock identification. The sulcus, a structure on the medial side of the otolith, is an important feature in morphological analysis. This study was conducted to evaluate the f...Otolith morphology is widely used for fish stock identification. The sulcus, a structure on the medial side of the otolith, is an important feature in morphological analysis. This study was conducted to evaluate the feasibility of using sulcus morphology for stock identification and to compare its performance with commonly used otolith morphology analysis. Otoliths were collected and analyzed from three geographical groups (the Huanghe (Yellow) River estuary, HHE;the Jiaozhou Bay, JZB;and the Changjiang (Yangtze) River estuary, CJE) of yellow drum Nibea albiflora. The results show that the analysis of sulcus morphology based on shape indices (SIs), elliptic Fourier coefficients (EFc), and a combination of the two parameters identified stocks at overall classification rates of 51.0%, 72.5%, and 73.2%, respectively. These classification rates are similar to those obtained using otolith morphology analysis (57.0%, 73.8%, and 76.5% by SIs, EFc, and their combination, respectively). The findings suggest that sulcus morphology is comparable to the commonly used otolith morphology for identifying stocks of sciaenids, such as the yellow drum. For both otolith and sulcus morphology, EFc could identify the stocks more efficiently than SIs, while the combination of SIs and EFc was even better.展开更多
This study analyzed and compared variations of the sulcus and otolith outlines of three geographic stocks(Huanghe(Yellow)River estuary(HHE),Jiaozhou Bay(JZB),and Changjiang(Yangtze)River estuary(CJE))of white croaker ...This study analyzed and compared variations of the sulcus and otolith outlines of three geographic stocks(Huanghe(Yellow)River estuary(HHE),Jiaozhou Bay(JZB),and Changjiang(Yangtze)River estuary(CJE))of white croaker Pennahia argentata in northern Chinese coastal waters.The sulcus and otolith outline analyses via elliptical Fourier transform(EFT,i.e.,outline analysis)achieved an overall classifi cation rate of 80.4%and 87.2%,respectively.Based on a combination of sulcus and otolith shape indices(SIs)and two derivative ratios,a moderate discriminatory effi ciency of 64.7%was obtained.The results indicate that sulcus outline analysis could be used alone to discriminate white croaker stocks,and that both sulcus and otolith outline analyses discriminated the fi sh stocks at a higher classifi cation rate than the shape indices.The sulcus outline analysis provided complementary information to the whole otolith outline analysis for stock discrimination.Both the sulcus and otolith outline analyses effi ciently discriminated between the most geographically separated CJE and HHE stocks,indicating that they could be considered discrete stocks for fi shery management.展开更多
基金The Brazilian Sao Paulo State Research Foundation(FAPESP)partially supported this research(grants 2012/15824-6 and 2012/07243-3)
文摘Geochemistry is a powerful tool to help characterize the tectonic setting of igneous rocks associations.However,when continental mafic dykes and flood basalts are the target most of the proposed geochemical discrimination diagrams fail to correctly classify them,i.e.many mafic
基金Supported by the National Key Basic Research Program of China(973Program)(No.2015CB453302)the NSFC-Shandong Joint Fund for Marine Science Research Centre(No.U1606404)
文摘Otolith morphology is widely used for fish stock identification. The sulcus, a structure on the medial side of the otolith, is an important feature in morphological analysis. This study was conducted to evaluate the feasibility of using sulcus morphology for stock identification and to compare its performance with commonly used otolith morphology analysis. Otoliths were collected and analyzed from three geographical groups (the Huanghe (Yellow) River estuary, HHE;the Jiaozhou Bay, JZB;and the Changjiang (Yangtze) River estuary, CJE) of yellow drum Nibea albiflora. The results show that the analysis of sulcus morphology based on shape indices (SIs), elliptic Fourier coefficients (EFc), and a combination of the two parameters identified stocks at overall classification rates of 51.0%, 72.5%, and 73.2%, respectively. These classification rates are similar to those obtained using otolith morphology analysis (57.0%, 73.8%, and 76.5% by SIs, EFc, and their combination, respectively). The findings suggest that sulcus morphology is comparable to the commonly used otolith morphology for identifying stocks of sciaenids, such as the yellow drum. For both otolith and sulcus morphology, EFc could identify the stocks more efficiently than SIs, while the combination of SIs and EFc was even better.
基金Supported by the National Natural Science Foundation of China(NSFC)under the Programs Science Fund for Creative Research Groups(Nos.40821004,41121064)。
文摘This study analyzed and compared variations of the sulcus and otolith outlines of three geographic stocks(Huanghe(Yellow)River estuary(HHE),Jiaozhou Bay(JZB),and Changjiang(Yangtze)River estuary(CJE))of white croaker Pennahia argentata in northern Chinese coastal waters.The sulcus and otolith outline analyses via elliptical Fourier transform(EFT,i.e.,outline analysis)achieved an overall classifi cation rate of 80.4%and 87.2%,respectively.Based on a combination of sulcus and otolith shape indices(SIs)and two derivative ratios,a moderate discriminatory effi ciency of 64.7%was obtained.The results indicate that sulcus outline analysis could be used alone to discriminate white croaker stocks,and that both sulcus and otolith outline analyses discriminated the fi sh stocks at a higher classifi cation rate than the shape indices.The sulcus outline analysis provided complementary information to the whole otolith outline analysis for stock discrimination.Both the sulcus and otolith outline analyses effi ciently discriminated between the most geographically separated CJE and HHE stocks,indicating that they could be considered discrete stocks for fi shery management.
