The absence of trees on the ground during the Qing Dynasty in China can be attributed to a combination of factors, including deforestation, overpopulation, and inefficient land management practices. According to historical records, the Qing Dynasty, which lasted from 1644 to 1912, experienced significant deforestation due to the rapid expansion of agriculture and the growing demand for wood and land for housing and infrastructure.

One of the primary reasons for the deforestation was the expansion of agricultural land. As the population grew, so did the need for more farmland to support the increasing food demand. This led to the clearing of forests to make way for crops. According to a study by the Chinese Academy of Sciences, the population of China increased from approximately 150 million in 1650 to over 400 million by the end of the Qing Dynasty. This dramatic increase in population put immense pressure on the land, leading to widespread deforestation.

Another contributing factor was the inefficient land management practices of the time. The Qing Dynasty government did not have effective policies to regulate land use and protect forests. This lack of regulation allowed for widespread illegal logging and land conversion. For instance, the demand for wood for construction and fuel increased significantly, leading to the depletion of forest resources.

Data from the Qing Dynasty's Revenue Records show that the government collected taxes on wood and land, but these revenues were not sufficient to fund conservation efforts. In fact, the government often encouraged deforestation for economic gain. The lack of economic incentives for conservation further exacerbated the problem.

Furthermore, the Qing Dynasty faced environmental challenges such as frequent droughts and floods, which made it difficult for forests to regenerate. These natural disasters, combined with human activities, led to the rapid degradation of the forest cover.

In conclusion, the absence of trees on the ground during the Qing Dynasty was primarily due to deforestation caused by the expansion of agriculture, overpopulation, inefficient land management, and the lack of conservation policies. These factors, combined with environmental challenges, resulted in the depletion of forest resources and the loss of biodiversity.