晚古生代华夏植物群绝灭以及中生代植物群由来问题，一直是古植物学界关注的热点。该问题解决有赖于深入了解有限的早、中三叠世植物群及其古气候背景。辽宁发现的唯一典型而又特殊的中三叠世林家植物群，兼含晚古生代和中生代成分，并含南、北半球类似属种。该植物群在上世纪80年代初步研究后未再研究，最近又有许多新的重要属种发现，如Glossopteris和Fascipteris stena。这一特殊植物群的古气候背景及复原等重要问题也均未研究。本项目拟通过样地法充分采集不同属种植物化石，在植物形态及表皮构造研究基础上，甄别植物群的中生代和古生代成分，对比南、北半球类似属种，分析该植物群的古气候、古地理背景，探讨植物群形成原因问题，并复原该植物群。本项目不仅对提高我国东北中三叠世植物群研究程度, 恢复我国东北中三叠世植被及古气候研究有重要意义，而且也为解决华夏植物群绝灭以及中生代植物群由来问题提供了可能的线索

Paleobotanists always focus on the problems about the extinction of the Late Paleozoic Cathaysia flora and the origin of the Mesozoic flora. The appropriate explanation should be based on enough information derived from the Early and Middle Triassic floras and its paleoclimatic background, which has been limitedly studied so far. The only typical and very special Middle Triassic Linjia Flora of Liaoning, not only contains Mesozoic components and Paleozoic components, but also includes similar taxa in the southern and northern hemispheres. The flora has not been studied since its discovery in the 1980th last century. Recently a lot of new important taxa are discovered, such as Glossopteris and Fascipteris stena. The paleoclimatic background and the reconstruction of the flora have also not been studied. We will select the sample method on a large scale to collect plant fossils, identify taxa and analyze the structures of epidermis, differentiate the Paleozoic components from the Mesozoic components, compare taxa with similar taxa in the southern and northern hemispheres, analyze its paleoclimatic and paleogeographic background, explore the reason of the flora present, and finally reconstruct the Linjia Flora. The implications for this project is not only to increase the degree of understanding the Middle Triassic flora of Northeast China, as well as reconstruct the Middle Triassic vegetation and climate of Northeast China, but also give a possible clue to interpret the extinction of the Late Paleozoic Cathaysia flora and the origin of the Mesozoic flora.