AmeriFlux AmeriFlux US-Bar Bartlett Experimental Forest

This is the AmeriFlux version of the carbon flux data for the site US-Bar Bartlett Experimental Forest. Site Description - The Bartlett Experimental Forest (448170 N, 71830 W) is located within the White Mountains National Forest in north-central New Hampshire, USA. The 1050 ha forest extends across an elevational range from 200 to 900 m a.s.l. It was established in 1931 and is managed by the USDA Forest Service Northeastern Research Station in Durham, NH. The climate is humid continental with short, cool summers (mean July temperature, 19.8C) and long, cold winters (mean January temperature, 9.8C). Annual precipitation averages 130 cm and is distributed evenly throughout the year. Soils are developed from glacial till and are predominantly shallow, well-drained spodosols. At lowto mid-elevation, vegetation is dominated by northern hardwoods (American beech, Fagus grandifolia; sugar maple, Acer saccharum; yellow birch, Betula alleghaniensis; with some red maple, Acer rubrum and paper birch, Betula papyrifera). Conifers (eastern hemlock, Tsuga canadensis; eastern white pine, Pinus strobus; red spruce, Picea rubens) are occasionally found intermixed with the more abundant deciduous species but are generally confined to the highest (red spruce) and lowest (hemlock and pine) elevations. In 2003, the site was adopted as a NASA North American Carbon Program (NACP) Tier-2 field research and validation site. A 26.5 m high tower was installed in a low-elevation northern hardwood stand in November, 2003, for the purpose of making eddy covariance measurements of the forest–atmosphere exchange of CO2, H2O and radiant energy. Continuous flux and meteorological measurements began in January, 2004, and are ongoing. Average canopy height in the vicinity of the tower is approximately 20–22 m. In the tower footprint, the forest is predominantly classified into red maple, sugar maple, and American beech forest types. Leaf area index in the vicinity of the tower is 3.6 as measured by seasonal litterfall collection, and 4.5 as measured by the optically based Li-Cor LAI-2000 instrument. Further site information: http://www.fs.fed.us/ne/durham/4155/bartlett.htm

本数据集为站点US-Bar（巴特利特实验林）的AmeriFlux版碳通量数据。站点说明：巴特利特实验林（坐标北纬44°8′17″，西经71°8′30″）坐落于美国新罕布什尔州中北部的怀特山国家森林境内，园区总面积1050公顷，海拔跨度为200~900米（海平面以上）。该林分始建于1931年，由美国农业部林务局（USDA Forest Service）东北研究站（位于新罕布什尔州达勒姆）负责管理。该地气候属于湿润大陆性气候：夏季短促凉爽，7月平均气温为19.8℃；冬季漫长寒冷，1月平均气温为9.8℃。年平均降水量达130厘米，全年降水分布相对均匀。土壤由冰碛物发育而成，以浅层、排水良好的灰土（spodosols）为主。在中低海拔区域，植被以北方硬阔林为绝对优势类群，包含美洲山毛榉（Fagus grandifolia）、糖枫（Acer saccharum）、黄桦（Betula alleghaniensis），伴生有红枫（Acer rubrum）与纸皮桦（Betula papyrifera）。针叶树种（东部铁杉Tsuga canadensis、东部白松Pinus strobus、红云杉Picea rubens）偶尔会与优势落叶树种混生，但通常仅局限分布于最高海拔区域（红云杉）与最低海拔区域（铁杉与松树）。2003年，该站点被纳入美国国家航空航天局（NASA）北美碳计划（NACP）二级野外研究与验证站点。同年11月，研究人员在一处低海拔北方硬阔林分中架设了一座高26.5米的通量塔，用于开展森林-大气间CO₂、H₂O及辐射能量的涡度协方差（eddy covariance）观测。2004年1月起，通量与气象数据的连续采集工作正式启动，目前监测仍在持续进行中。塔周边区域的平均冠层高度约为20~22米。通量塔足迹范围内的森林主要划分为红枫、糖枫与美洲山毛榉林型。通过季节性凋落物收集法测得塔周边的叶面积指数（LAI）为3.6，而采用基于光学原理的Li-Cor LAI-2000仪器测得的叶面积指数为4.5。更多站点相关信息可访问：http://www.fs.fed.us/ne/durham/4155/bartlett.htm

搜集汇总

背景与挑战

背景概述

该数据集是AmeriFlux版本的碳通量数据，来自美国新罕布什尔州Bartlett实验森林站点。它通过涡度协方差测量从2004年起持续监测森林与大气间的CO2、H2O和辐射能量交换，站点作为NASA北美碳计划研究站点，支持长期生态和气候研究。