Quantifying the interactions between topography, climate and plant diversity within one of the world's biodiversity hotspots, the southeastern margin of the Tibetan Plateau, remains elusive due to few reliable quantitative paleoelevation reconstructions, precise geological age constraints and well-preserved plant fossils. The Lühe Basin, on the southeastern margin of Tibetan Plateau has yielded abundant plant fossils with a U-Pb age of 33–32 Ma, providing an opportunity to estimate the elevation of this region and plant diversity at that time. Fossil leaf physiognomy was used to reconstruct the paleoclimate and the paleoelevation of the basin was derived from moist enthalpy. The results show that the Lühe Basin, had attained it's present elevation (1.7 ± 0.9 km) by the early Oligocene and, compared to now, experienced a humid subtropical climate with a wetter dry season and lower precipitation seasonality in an overall wetter precipitation regime (1748.5 ± 606 mm). This was accompanied by a greater seasonal range in temperature, although the mean annual temperature (14.9 ± 2.3 °C) was similar to that of today (15.6 °C). Combined with previous studies, we conclude that the appearance of the modern flora across the southeastern margin of the Tibetan Plateau had started by the early Oligocene, corresponding with the establishment of modern topography at that time.

由于缺乏可靠的定量古海拔重建、精确的地质年龄限制和保存完好的植物化石，在世界生物多样性热点之一——青藏高原东南缘，对地形、气候和植物多样性之间的相互作用进行量化仍然难以捉摸。青藏高原东南缘的潞河盆地出土了丰富的植物化石，U-Pb年龄为33~32 Ma，为估计该地区当时的海拔高度和植物多样性提供了机会。化石叶面相被用来重建古气候，盆地的古海拔来自湿焓。结果表明，在渐新世早期，潞河盆地已达到现在的海拔高度（1.7±0.9 km），与现在相比，经历了湿润的亚热带气候，旱季较湿润，降水季节性较低，总体降水量较大（1748.5 ± 606 mm）。尽管年平均温度（14.9 ± 2.3 °C）与今天（15.6 °C）相似，但伴随着更大的季节性温度范围。结合前人的研究，我们得出结论，青藏高原东南缘现代植物群的出现始于渐新世早期，与当时现代地形的形成相对应。