Natural conditions

Nanjing is tectonically located on the northern margin of the Yangtze Block that is based on low-grade metamorphic schist and metamorphic volcanics with an isotopic age of roughly 864 million to 1,031 million years. Above the basement, the sediment layer is approximately 8,000 to 9,000 meters thick, being categorized into a Sinian-to-Quaternary sequence. As Nanjing is geomorphically part of the Ning-Zhen-Yang Mountainous Area, approximately 60.8% of its territory consists of low mountains, hills and mounds, while the remaining 39.2% comprises plains, depressions, rivers and lakes.

Blessed with a typical humid northern subtropical climate, Nanjing has four distinct seasons, abundant rainfall, shorter springs and autumns, and a relatively wide temperature range. Northeasterly and southeasterly winds predominate in the winter and summer, respectively. The annual average temperature of Nanjing in 2022 was 16.9 ℃ or 0.5 ℃ higher than the average for a typical year. Moreover, the annual precipitation reached 819.8 millimeters, along with 2,138.6 hours of sunshine. Because the annual average temperature approached or reached the record high, there was less precipitation but more sunshine than in other years. Thus, Nanjing was graded as medium-low in the annual general climate assessment.    

Taxonomically, the primary soil types of Nanjing are zonal and agricultural. The zonal soil in the northern and middle regions of Nanjing is yellowish brown, and there is red soil in the southern region bordering to Anhui Province. Additionally, the agricultural soil formed by human farming is basically paddy soil, along with some yellow hard soil (referred to as Huang Gang) and vegetable soil. The distribution of soils follows certain patterns, which depend on geomorphic and hydrological features and are categorized into three major types: low-mountain and hill soil, mound soil, and plain soil.