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| Changes in history | Date | Historical details | References |
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| Increase in the ratio of rice paddies to total cultivated land | 15th to 18th century | Piling up reservoirs or dams to turn wetlands into rice paddy fields. At the late 17th to 18th century, rice cultivation became dominant in the agriculture of Joseon Dynasty. | [63, 73] |
| 18th to 19th century | Changing cultivated dry fields to the rice paddies (42.9% in 1759 to 68.6% in 1901). One-third of rice paddies of Joseon Kingdom was created at this period. | [73–75, 78, 79] |
| Japanese colonial period | Changing the dry field to rice paddies still continued in colonial Korea. Anopheles sinensis, the vector mosquito of malaria in Korea, usually propagates in the stagnant water of rice paddies. Malaria infection was thus very common in the places. | [54, 79] |
| US military administration | Trying to get rid of such mosquito propagation spots by making gutters to drain the water. | [79] |
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| Construction of reservoirs or dams | 15th to 19th century | From the late 15th century on, the irrigation system such as reservoirs and dams were actively built in Korea. The water in the dams could be drained into the paddies for rice cultivation. The construction and maintenance of irrigation system was governed by government or gentries in countryside (16th century). In the early 19th century, the number of reservoirs or dams reached as many as 5,960 in Korea. The construction of dams and reservoirs reached the peak in the early 19th century, maintained even in Japanese colonial period. | [54, 63, 74, 75, 78] |
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| Simplification of crop types | Since 18th century | To benefits from higher productivity of rice farming and respond the market demands much efficiently, the proportion of rice in cereal cultivation has been greatly expanded. | [73] |
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| Clearing and reclamation of the land; Slash and burn in mountain area | 15th to 18th century | Large-scale reclamation was taking place in abandoned land, wetland, coastal, and low-lying areas at river or stream basins (15th to 17th century). Slash and burn increased in mountainous area (since 17th century). Previous ranch and isolated islands were also turned into farmland. The nonfarming backdrops almost disappeared throughout the country after mid-17th century. | [73–77] |
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| Deforestation | Since 17th century | Population growth in Joseon society led to increased demand for forest products. Serious deforestation at this stage was also caused by slash-and-burn farming (after 17th century on). At this stage, approximately 40–50 percent of the cropland in Joseon Kingdom was prepared by slash-and-burn farming, causing deforestation in the mountain area. In mid-17th century, no matter how deep the mountain area was, there was no place where no cropland was. Deforestation induced frequent landslides and floods. | [63, 73, 76] |
| Colonial period | Deforestation appears to have induced malaria in colonial period Korea. | [54] |
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| Population increasing | Mid-16th century | 9 to 10 million people in Korean peninsula. | [73] |
| Late 18th century | Population in Korean peninsula reached 15 million. The increase in population at this stage appears to have been due to the high productivity of rice cultivation in Korean peninsula at that time. | [73, 76] |
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