[Characteristics of Nitrogen Deposition in Heilongjiang Liangshui National Nature Reserve]

To investigate the nitrogen deposition status in Heilongjiang Liangshui National Nature Reserve, a G78 nitrogen deposition collector was used to monitor dry particulate nitrogen deposition and wet nitrogen deposition during the growing season in 2015, and a bucket was used to monitor bulk nitrogen deposition during non-growing season. The results showed that:①Total nitrogen deposition (wet nitrogen deposition+dry particulate nitrogen deposition during the growing season and bulk deposition during the non-growing season) was 12.93 kg·(hm²·a)^-1, inorganic nitrogen deposition was 8.27 kg·(hm²·a)^-1 with NH₄⁺/NO₃^- ratio of 1.3; organic nitrogen deposition was 4.66 kg·(hm²·a)^-1, which was equivalent to 36.0% of the total nitrogen deposition. ②Total nitrogen deposition in the growing season (wet+dry particulate deposition) and non-growing season (bulk deposition) were 11.42 kg·hm^-2 and 1.51 kg·hm^-2respectively, which account for 88.3% and 11.7% of the total nitrogen deposition respectively. ③Total wet nitrogen deposition during the growing season was 9.28 kg·hm^-2, contributing to 81.3% of the total nitrogen deposition in the growing season, and was positively correlated with precipitation (R²=0.87, P<0.001); total dry particulate nitrogen deposition in the growing season was 2.14 kg·hm^-2, which was 18.7% of the total nitrogen deposition in growing season. Wet nitrogen deposition in this region is moderate compared with other regions in China, and is significantly affected by precipitation. There is a potential risk of environmental pollution in this region. Thus, environmental protection and water quality monitoring are required in the process of production.