N-deposition_tree_ring_isotopes_Gharun

Dataset and code related to manuscript to be submitted to Nature. Manuscript title is: Neglected role of nitrogen on positive CO2 effect over the 20th century. Dataset includes nitrogen deposition, climate variables, and stable isotopes in tree rings during the 20th century for two widespread European tree species.本数据集及配套代码均服务于一篇拟提交至《自然》（Nature）的学术手稿。 该手稿的标题为：《20世纪二氧化碳（CO₂）正效应中被忽视的氮素作用》。本数据集涵盖20世纪期间两种广泛分布的欧洲树种的氮沉降（nitrogen deposition）、气候变量以及树轮稳定同位素数据。