Northern Hemisphere Biome-and Process-Specific Changes in Forest Area and Gross Merchantable Volume: 1890-1990 (DB1017)

This database lists annual changes in areal extent (Ha) and gross merchantable wood volume (m3) produced by depletion and accrual processes in boreal and temperate forests in Alaska, Canada, Europe, Former Soviet Union, Non-Soviet temperate Asia, and the contiguous United States for the years 1890 through 1990. Forest depletions (source terms for atmospheric CO2) are identified as forest pests, forest dieback, forest fires, forest harvest, and land-use changes (predominantly the conversion of forest, temperate woodland, and shrubland to cropland). Forest accruals (sink terms for atmospheric CO2) are identified as fire exclusion, fire suppression, and afforestation or crop abandonment. The changes in areal extent and gross merchantable wood volume are calculated separately for each of the following biomes: forest tundra, boreal softwoods, mixed hardwoods, temperate softwoods, temperate hardwoods, and temperate wood- and shrublands. For access to the data files, click this link to the CDIAC data transition website: http://cdiac.ess-dive.lbl.gov/epubs/db/db1017/db1017.html本数据库收录了1890年至1990年间，阿拉斯加、加拿大、欧洲、前苏联、非苏联温带亚洲以及美国本土的寒带与温带森林，因耗竭与累积过程产生的面积（公顷，Ha）年变化量与总可售木材蓄积量（立方米，m³）。其中森林耗竭（大气二氧化碳的源项）涵盖森林病虫害、森林衰退、森林火灾、森林采伐以及土地利用变化（主要为森林、温带林地与灌丛向农田的转换）；森林累积（大气二氧化碳的汇项）涵盖防火隔离、灭火措施以及造林或农田撂荒。上述面积与总可售木材蓄积量的变化量，分别针对以下6类生物群系单独计算：森林苔原、寒带软木林、混交阔叶林、温带软木林、温带阔叶林以及温带林灌群落。如需获取数据文件，请点击此链接跳转至CDIAC数据转换网站：http://cdiac.ess-dive.lbl.gov/epubs/db/db1017/db1017.html