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运用叶缘分析法(LMA)、气候叶相分析多变量程序(CLAMP)和共存因子分析法(CA)定量重建云南景谷中新世植物群的古气候.对不同方法的结果进行分析比较和交叉验证,得出景谷古气候主要参数:年均温为16.0±1.3℃、最暖月均温为26.3±1.5℃、最冷月均温为6.2±2.6℃、生长季为8.6±0.7个月、生长季降雨量为1 492±218 mm、连续3个最湿月降水为701±139 mm和连续3个最干月降水为170±41 mm.这些数据反映了景谷中新世气候应属于南-中亚热带气候类型.同时,该植物群含有大量热带植物区系成分,也支持这一结论.另外,景谷地区早中新世温度、降水量季节性差异可能暗示了当时已经出现较弱的季风信号,但强烈的典型季风气候体系在当时可能尚未建立.“,”The paleoclimate of the Early Miocene Jinggu megaflora in Yunnan was quantitatively reconstructed here by application of three techniques to its taxonomic and morphotype samples,i.e.Leaf Margin Analysis (LMA),Climate-Leaf Analysis Multivariate Program (CLAMP),and the Coexistence Approach (CA).Detailed comparisons of various methods for accuracy in paleoclimatic estimates on this fossil flora were also presented.Thus,comprehensive consideration and cross validation of the results indicate that the most probable paleoclimatic estimates are 16.0 ± 1.3 ℃ for mean annual temperature (MAT),26.3 ± 1.5 ℃ for warmest month mean temperature (WMMT),6.2 ±2.6 ℃ for the coldest month mean temperature (CMMT),8.6±0.7 months for the growing season (GRS),1 492 ± 218 mm for growing season precipitation (GSP),701± 139 mm for the precipitation during the three consecutive wettest months(3-WET) and 170±41 mm for the precipitation during the three consecutive driest months (3-DRY).The results represent a southern-central subtropical climate in Jinggu during the Early Miocene,which is favored by the existence of many tropical elements in this paleoflora.Furthermore,the seasonality in temperature and precipitation during the Early Miocene was not conspicuous enough,which implies that a weak monsoonal signal other than the strong monsoon climate regime possibly occurred at that time.