Cary potential nitrogen mineralization data 1994 to 2005

The Forest Response to Stress and Damage (frequently referred to as FORSTAD) and long term forest monitoring project began in 1992 to study how mixed-oak forests respond to multiple forms of environmental change. The research took place at Cary Institute of Ecosystem Studies in the Hudson Valley of New York. FORSTAD included several sub-projects including (1) air pollution and nutrient cycling, (2) spongy moth dynamics, (3) small mammal dynamics and (4) vegetation dynamics.This dataset is a contribution to the Cary Institute of Ecosystem Studies, and is part of the Long term monitoring of forest ecosystems: air pollution and nutrient cycling archive.To understand the effects of air pollution on forests, the chemistry of the precipitation as it fell onto and through the forest was measured. In addition, the chemistry of the soil where tree roots grew as well as the chemistry of leaves were measured. Lastly, to understand how the microbes in soil were affected by pollution, the breakdown of plant material into nitrogen that could be taken up by tree roots was measured. This latter process is called nitrogen cycling or nitrogen mineralization. The measurements included throughfall amount and chemistry, soil solution amount and chemistry, foliar chemistry, litterfall and frassfall amount and carbon (C) and nitrogen (N) concentration, potential N mineralization and nitrification. Datasets include, soil water, throughfall, leaf litter and nitrogen cycling.The data presented here are extractable amounts of ammonium and nitrate (expressed as the concentration of N in micrograms N/gram dry weight soil), and the rates of nitrogen mineralization and nitrification (expressed as a rate of micrograms N/ gram dry weight soil/ day). Data are site-wide means for each soil horizon.<b>File list:</b>pj_ltm_data_n_mineralization_metadata.pdf - contains complete project metadata, personnel, methodology, and definitions for data variables in data file.pj_ltm_data_n_mineralization_1994-2005.csv

森林胁迫与损伤响应（常简称为FORSTAD）长期森林监测项目于1992年启动，旨在研究杂栎林如何响应多种环境变化。该研究在美国纽约哈德逊谷的卡里生态系统研究所（Cary Institute of Ecosystem Studies）开展。FORSTAD包含四个子项目，分别为：(1) 空气污染与养分循环；(2) 舞毒蛾（Spongy Moth）种群动态；(3) 小型哺乳动物种群动态；(4) 植被动态。

本数据集是对卡里生态系统研究所的贡献，隶属于《森林生态系统长期监测：空气污染与养分循环》档案。

为探明空气污染对森林的影响，研究人员对沉降至林内及穿透林冠的降水的化学组成进行了测定。此外，还测定了树木根系生长区域的土壤化学组成以及叶片的化学组成。最后，为明确土壤微生物如何受污染影响，研究人员测定了植物残体分解为可被树木根系吸收的氮的过程——这一过程被称为氮循环或氮矿化作用。

本次测定涵盖的指标包括：穿透雨量及其化学组成、土壤溶液量及其化学组成、叶片化学组成、枯落物与虫粪沉降量及其碳（C）、氮（N）浓度，以及潜在氮矿化与硝化速率。本数据集包含土壤水、穿透水、叶片枯落物及氮循环相关数据。

此处呈现的数据为铵态氮与硝态氮的可提取量（以每克干土中氮的微克数为单位，即μg N/g干土），以及氮矿化速率与硝化速率（以每日每克干土中氮的微克数为单位，即μg N/(g干土·天)）。数据为各土壤发生层的样地平均值。

文件清单：
pj_ltm_data_n_mineralization_metadata.pdf —— 包含完整的项目元数据、人员信息、研究方法以及数据文件中各数据变量的定义。
pj_ltm_data_n_mineralization_1994-2005.csv