外来植物对气候变化的反应更明显

Warming temperatures in Ohio are a key driver behind changes in the state's landscape, and non-native plant species ¹ appear to be responding more strongly than native wildflowers to the changing climate, new research suggests. This adaptive nature demonstrated by introduced species could serve them well as the climate continues to warm. At the same time, the non-natives' potential ability to become even more invasive could threaten the survival ² of native species already under pressure from land-use changes, researchers say., ,The research combines analyses of temperature change and blooming patterns of 141 species of Ohio wildflowers since 1895. Overall, the average temperature increased 1.7 degrees Fahrenheit ³ (0.9 degrees Celsius) in Ohio between 1895 and 2009. And 66 wildflower species -- or 46 percent of the 141 studied -- flowered earlier than usual in response to that warming., ,This change in flowering patterns not only alters the landscape, but affects the availability of food for insects and birds and can influence the reproductive success of the plants themselves., ,This kind of wildflower data is difficult to come by because historical observations of flowering trends simply don't exist in most states., ,Ohio State University graduate student Kellen Calinger collected her flowering pattern data from the university's herbarium（植物标本）, which contains more than 500,000 plant specimens ⁴. Accessing this treasure trove ⁵ of specimens complete with data on their location and the date they were harvested has led her to produce one of the six largest such datasets in the world tracking the history of the wildflower life cycle in response to climate change., ,"This is a new way of assessing conservation. Not only are the results important, but so is the method that allowed me to produce these results," said Calinger, a Ph.D. candidate in the Department of Evolution, Ecology and Organismal Biology at Ohio State., ,"I hope not only to look at climate change impacts and predict potential species extinctions as a result of climate change in Ohio, but also hope my methods will allow people throughout the country to assess impacts in their areas and allow us all to make informed decisions about protecting these areas," she said., ,Calinger described her research in a talk October 5 at EcoSummit 2012, an international conference held in Columbus., ,Calinger documented temperature change in Ohio with data kept since 1895 by 26 weather stations located throughout the state as part of the U.S. Historical Climatology Network.