The Chinese Grouse (Tetrastes sewerzowi) is a rare, endemic bird in China, inhabiting conifer-dominated mountain forests. Both the natural fragmentation and heavy cutting of mature forests have resulted in patchy grou...The Chinese Grouse (Tetrastes sewerzowi) is a rare, endemic bird in China, inhabiting conifer-dominated mountain forests. Both the natural fragmentation and heavy cutting of mature forests have resulted in patchy grouse habitats. We used SPOT (XS-sensor) satellite imagery to discriminate between open land and conifer or broadleaf forests. The area analyzed is about 120000 ha in size and includes the Lianhuashan Nature Reserve and the Yeliguan Forestry Park. We identiifed 4111 ha of mature coniferous forests in 229 patches (maximum 332 ha, mean 18 ha) as the habitat used by Chinese Grouse throughout the year. We examined 31 forest islands of different sizes and degrees of isolation for the presence of Chinese Grouse. We used generalized linear models (GLM) with binomial error structure and logit link function to estimate the probability of Chinese Grouse occupancy in a forest fragment. Habitat patch size (hs) and distance to the next occupied fragment (doc) were used as predictor variables, important for occupancy. Small habitat islands were disproportionately less likely to be occupied than large, nearby habitats. There was a clear speciifc habitat size of about 40 ha, above which habitat fragments were occupied more often. Suitable habitat fragments isolated by more than 2 km appeared to be inaccessible to Chinese Grouse. The results have been used in reforestation projects to establish linking corridors in the study area.展开更多
Sinopodophylli Fructus is the commonly used traditional Tibetan medicinal herb. In the present study, we established a reversed-phase high performance liquid chromatography method to simultaneously determine three lig...Sinopodophylli Fructus is the commonly used traditional Tibetan medicinal herb. In the present study, we established a reversed-phase high performance liquid chromatography method to simultaneously determine three lignans and five flavonoid constituents, namely podophyllotoxin, desoxypodophyUotoxin, 4＇-demethyldesoxypodophyllotoxin, 8-prenylkaemferol, quercetin, kaempferol, 8,2＇-diprenylquercetin 3-methylether and 8-prenylquercetin, in Sinopodophylli Fructus. The chromatographic separation was achieved on a C_18 analytical column with a gradient mobile phase consisting of acetonitrile and 0.05% phosphoric acid at a flow rate of 1.0 mL/min. UV detection was set at 290 nm and 370 rim, and the column oven was set at 35℃. This method provided a good reproducibility, and its overall intra- and inter-day precision was less than 3% and 4%, respectively. The recovery of the method was 98.29%-101.60%, and a good linearity （R2≥0.9992） was obtained for all the analytes over a relatively wide range of concentration. A total of 17 samples ofS. hexandrum （12 fruits, 5 roots and rhizomes） were collected from different areas and then successfully quantified. The results indicated that the contents of eight compounds significantly varied （the sum content ranged from 16.90 to 55.68 mg/g）, and prenylated fiavonoids could be used as marker constituents in the identification and quality control of Sinopodophylli Fructus.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.31270468,30620130110)
文摘The Chinese Grouse (Tetrastes sewerzowi) is a rare, endemic bird in China, inhabiting conifer-dominated mountain forests. Both the natural fragmentation and heavy cutting of mature forests have resulted in patchy grouse habitats. We used SPOT (XS-sensor) satellite imagery to discriminate between open land and conifer or broadleaf forests. The area analyzed is about 120000 ha in size and includes the Lianhuashan Nature Reserve and the Yeliguan Forestry Park. We identiifed 4111 ha of mature coniferous forests in 229 patches (maximum 332 ha, mean 18 ha) as the habitat used by Chinese Grouse throughout the year. We examined 31 forest islands of different sizes and degrees of isolation for the presence of Chinese Grouse. We used generalized linear models (GLM) with binomial error structure and logit link function to estimate the probability of Chinese Grouse occupancy in a forest fragment. Habitat patch size (hs) and distance to the next occupied fragment (doc) were used as predictor variables, important for occupancy. Small habitat islands were disproportionately less likely to be occupied than large, nearby habitats. There was a clear speciifc habitat size of about 40 ha, above which habitat fragments were occupied more often. Suitable habitat fragments isolated by more than 2 km appeared to be inaccessible to Chinese Grouse. The results have been used in reforestation projects to establish linking corridors in the study area.
基金National Key Technology R&D Program"New Drug Innovation"of China(Grant No.2009ZX09308-004,2013ZX09103002-006)
文摘Sinopodophylli Fructus is the commonly used traditional Tibetan medicinal herb. In the present study, we established a reversed-phase high performance liquid chromatography method to simultaneously determine three lignans and five flavonoid constituents, namely podophyllotoxin, desoxypodophyUotoxin, 4＇-demethyldesoxypodophyllotoxin, 8-prenylkaemferol, quercetin, kaempferol, 8,2＇-diprenylquercetin 3-methylether and 8-prenylquercetin, in Sinopodophylli Fructus. The chromatographic separation was achieved on a C_18 analytical column with a gradient mobile phase consisting of acetonitrile and 0.05% phosphoric acid at a flow rate of 1.0 mL/min. UV detection was set at 290 nm and 370 rim, and the column oven was set at 35℃. This method provided a good reproducibility, and its overall intra- and inter-day precision was less than 3% and 4%, respectively. The recovery of the method was 98.29%-101.60%, and a good linearity （R2≥0.9992） was obtained for all the analytes over a relatively wide range of concentration. A total of 17 samples ofS. hexandrum （12 fruits, 5 roots and rhizomes） were collected from different areas and then successfully quantified. The results indicated that the contents of eight compounds significantly varied （the sum content ranged from 16.90 to 55.68 mg/g）, and prenylated fiavonoids could be used as marker constituents in the identification and quality control of Sinopodophylli Fructus.
