UPDATED MARCH 7, 2024
As Napoleon Bonaparte once said "an army marches on its stomach.", the importance of military logistics simply cannot be overstated. In a sense, military logistics can be seen as the single most important factor that decides whether a war is won or lost, even more so than military stratagem or technology.
Due the fact that Chinese fought most of their wars on their own soil or on barren steppes and deserts, foraging was either impractical (nothing to forage) or strongly discouraged/outright banned. Thanks to China's centralised governance and military organisation, it had a remarkably sophisticated logistical system for its time that could provision its armies effectively and remove the dependency on foraging (although foraging/pillaging still happened from time to time). Unfortunately, even the most robust logistical system had its failings. As such, emergency rations were issued to supplement regular military rations, and generals were taught survival skills in case of severe food shortage.
Military ration, known as Qiu Bei (糗糒, lit. 'Dry food') and Ji Liang (齎糧, lit. 'Supplied food') in Classical Chinese, generally remained consistent throughout many dynasties as dietary culture changes slowly. In fact, Ming Chinese inherited most of their standardised military rations from their Song ancestors.