“双循环”背景下，国际学术交流的减少可能会加剧研究型大学的近亲繁殖状况，学术近亲繁殖与创新型人才的培养存在着矛盾。

本研究选取C9联盟高校4个学科，基础学科中的物理学、数学，应用学科中的材料科学、环境科学共924位教师作为研究对象，探讨近亲繁殖的产生条件、学缘关系的学科差异以及对学术产出的影响等问题。

研究发现：不同院校间的学缘关系差异较大，交通便利、地处经济发达地区、实力较强的学校学术近亲繁殖程度较低，反之则较高；学缘关系存在学科差异，学科的相对硬度（FGA值）越高，近亲繁殖越严重，应用学科的近亲繁殖高于基础学科，材料科学的学术近亲繁殖情况最严重，物理学的学缘关系多样性相对较好；有一定学缘关系但尚未达到近亲繁殖程度的学者学术产出表现更好，近亲繁殖与学术产出负相关，在应用学科领域，材料科学、环境科学中有一定学缘关系的学者产出质量最高，而在基础学科中有一定程度近亲繁殖的学者其科研产出的质量更高。在C9高校中，有学士、硕士学缘关系的学者在学术产出的质量和影响力方面均有明显优势。此外，研究还发现学术头衔会提高学者的学术产出，“非升即走”会降低学术产出的质量。

基于上述研究结果，本研究提出相应政策建议：应客观看待学术近亲繁殖现象；内陆地区的院校应拓宽学者聘用范围；应用学科应允许一定程度的学术近亲繁殖；高校在聘用和培养人才方面可选择有一定程度近亲繁殖的学者。

In the context of the "double cycle", the decrease of international academic exchanges may aggravate the inbreeding of research universities, and there is a contradiction between academic inbreeding and the cultivation of innovative talents.

In this study, a total of 924 teachers from 4 disciplines in C9 alliance universities, including physics and mathematics in basic disciplines and materials science and environmental science in applied disciplines, were selected as research objects to discuss the conditions for the generation of inbreeding, the disciplinary differences of learning relationship and the impact on academic output.

The results show that there is a great difference in the academic relationship among different institutions. The degree of academic inbreeding is lower in the schools with convenient transportation, located in the economically developed areas, and the degree of academic inbreeding is higher in the schools with strong strength. The higher the relative hardness (FGA value) of the discipline, the more serious the inbreeding, the more serious the inbreeding of the applied discipline was higher than that of the basic discipline, the most serious the inbreeding of the material science, the more diverse the relationship of the physics. Scholars who have a certain degree of academic relationship but have not reached the degree of inbreeding have better academic output performance, and inbreeding is negatively correlated with academic output. In applied disciplines, scholars with a certain degree of academic relationship in materials science and environmental science have the highest output quality, while scholars with a certain degree of inbreeding in basic disciplines have a higher quality of scientific output. In C9 universities, scholars with bachelor's and master's degrees have a distinct advantage in terms of the quality and influence of academic output. In addition, the research also found that academic titles can improve academic output, and "up or out" can reduce the quality of academic output.

Based on the above research results, this study puts forward corresponding policy recommendations: the phenomenon of academic inbreeding should be viewed objectively; Institutions in inland areas should broaden the scope of academic recruitment; Applied disciplines should allow a certain degree of academic inbreeding; Universities can select scholars with a certain degree of inbreeding when hiring and cultivating talents.