Biotic Homogenization Caused by the Invasion of Solidago canadensis in China

Although studies argue that invasive species can cause biotic differentiation,some cases show that biological invasions actually decrease biodiversity through biotic homogenization.The concept of biotic homogenization through the invasion of a certain serious invasive plant species merit more studies.Hence,we used field surveys to quantitatively compare invasive populations of Solidago canadensis(SC) in China with the control sites(adjacent sites to SC present sites yet without the species) and SC native populations in the USA.We found that plant communities in SC invaded habitats shared similarities with those in SC native ranges.Bray-Curtis similarity clearly showed that the composition of plant communities in SC invaded habitats were similar to those in SC native ranges.Both in the native and introduced range,plant communities with SC present were characterized by SC being dominant,significantly lower species richness,α-diversity and β-diversity,as well as a decrease in the correlation coefficient between geographic distance and floristic similarities.SC favors fertile and moist loam habitat,while it dominated in various habitats in China,where more than 20 different dominants should have occurred.In conclusion,serious invasive species can quickly remodel and homogenize diverse communities by dominating them.     

Reducing risks of Salmonella infections in poultry

3预防沙门氏菌传播的措施 3.1卫生和消毒 在引进新一批鸡群前,所有鸡舍和器具必须进行清洁消毒,特别是在前一批鸡群为沙门氏菌阳性的情况下,清洁消毒就更有必要.卫生措施的有效性可通过严格的细菌学定量检测验证,要求肠道细菌计数小于103个/25 m2.