This study is part of the endeavor to construct a comprehensive DNA barcoding database for common seaweeds in China. Identifications of red seaweeds, which have simple morphology and anatomy, are sometimes difficult s...This study is part of the endeavor to construct a comprehensive DNA barcoding database for common seaweeds in China. Identifications of red seaweeds, which have simple morphology and anatomy, are sometimes difficult solely depending on morphological characteristics. In recent years, DNA barcode technique has become a more and more effective tool to help solve some of the taxonomic difficulties. Some DNA markers such as COI（cytochrome oxidase subunit I） are proposed as standardized DNA barcodes for all seaweed species. In this study, COI, UPA （universal plastid amplicon, domain V of 23S rRNA）, and ITS （nuclear internal transcribed spacer） were employed to analyze common species of intertidal red seaweeds in Qingdao （119.3°-121°E, 35.35°-37.09°N）. The applicability of using one or a few combined barcodes to identify red seaweed species was tested. The results indicated that COI is a sensitive marker at species level. However, not all the tested species gave PCR amplification products due to lack of the universal primers. The second barcode UPA had effective universal primers but needed to be tested for the effectiveness of resolving closely related species. More than one ITS sequence types were found in some species in this investigation, which might lead to confusion in further analysis. Therefore ITS sequence is not recommended as a universal barcode for seaweeds identification.展开更多
An improved cluster thermal time constant(CTTC) and surface thermal time constant(STTC) numerical model was introduced,which took into account the effect of vegetation coverage and modified the expression of net longw...An improved cluster thermal time constant(CTTC) and surface thermal time constant(STTC) numerical model was introduced,which took into account the effect of vegetation coverage and modified the expression of net longwave radiation of the canyon layer.In the case study the model was used to calculate the air temperature variation at downtown of Tianjin City.The relative error between the calculated and measured air temperatures was less than 3%.The tendency of air temperature variation was predicted when the building aspect ratio,vegetation rate,and wind speed changed respectively.It is demonstrated that when the aspect ratio of a building with south-north orientation increased,the heat island intensity at day time was mitigated;however,it became worse after sunset.The vegetation coverage rate and wind speed both had negative relationship with the urban heat island intensity.展开更多
基金supported by the National Special Research Fund for Non-Profit Sector (Agriculture) (No. 200903030)the National Natural Science Foundation of China (No.41176135)
文摘This study is part of the endeavor to construct a comprehensive DNA barcoding database for common seaweeds in China. Identifications of red seaweeds, which have simple morphology and anatomy, are sometimes difficult solely depending on morphological characteristics. In recent years, DNA barcode technique has become a more and more effective tool to help solve some of the taxonomic difficulties. Some DNA markers such as COI（cytochrome oxidase subunit I） are proposed as standardized DNA barcodes for all seaweed species. In this study, COI, UPA （universal plastid amplicon, domain V of 23S rRNA）, and ITS （nuclear internal transcribed spacer） were employed to analyze common species of intertidal red seaweeds in Qingdao （119.3°-121°E, 35.35°-37.09°N）. The applicability of using one or a few combined barcodes to identify red seaweed species was tested. The results indicated that COI is a sensitive marker at species level. However, not all the tested species gave PCR amplification products due to lack of the universal primers. The second barcode UPA had effective universal primers but needed to be tested for the effectiveness of resolving closely related species. More than one ITS sequence types were found in some species in this investigation, which might lead to confusion in further analysis. Therefore ITS sequence is not recommended as a universal barcode for seaweeds identification.
文摘An improved cluster thermal time constant(CTTC) and surface thermal time constant(STTC) numerical model was introduced,which took into account the effect of vegetation coverage and modified the expression of net longwave radiation of the canyon layer.In the case study the model was used to calculate the air temperature variation at downtown of Tianjin City.The relative error between the calculated and measured air temperatures was less than 3%.The tendency of air temperature variation was predicted when the building aspect ratio,vegetation rate,and wind speed changed respectively.It is demonstrated that when the aspect ratio of a building with south-north orientation increased,the heat island intensity at day time was mitigated;however,it became worse after sunset.The vegetation coverage rate and wind speed both had negative relationship with the urban heat island intensity.
