AmeriFlux US-Ha2 Harvard Forest Hemlock Site

This is the AmeriFlux version of the carbon flux data for the site US-Ha2 Harvard Forest Hemlock Site. Site Description - The forest surrounding the Hemlock site has remained pristine with two exceptions. In the early to mid-1700s, European settlers cleared the majority of the forest for agricultural purposes. Selective harvesting of hemlock and chestnut trees occurred up until the early 1900s, when the chestnut blight killed all of the chestnut trees. In the current forest, about 83% of the total basal area of trees is hemlock. The remainder is equally divided between eastern white pine (Pinus strobus L.) and deciduous species, including red maple (Acer rubrum), red oak (Quercus rubra) and black birch (Betula lenta). A very thick organic layer (10-20 cm or more) covers the soil surface, and highly decayed coarse woody debris is abundant.

本数据集为哈佛森林铁杉站点（US-Ha2）碳通量数据的AmeriFlux版本。站点描述 - 铁杉站点周边的森林大体保持原始状态，但存在两处例外情况。18世纪早中期，欧洲殖民者为农业目的砍伐了大部分森林。选择性采伐铁杉和栗树的活动持续至20世纪初，彼时栗树疫病（chestnut blight）导致所有栗树死亡。当前森林中，树木总断面积的约83%为铁杉；剩余部分则由东部白松（Pinus strobus L.）与落叶树种均分，后者包括红枫（Acer rubrum）、红栎（Quercus rubra）及黑桦（Betula lenta）。土壤表面覆盖着一层极厚的有机质层（厚度达10-20厘米或更甚），且高度腐烂的粗木质残体（coarse woody debris）含量丰富。