黑龙江长白山森林生物量的时空变化分析

森林生物量碳储量的空间分布及其变化信息, 对揭示地表空间变化规律及驱动因子、分析评价森林生产力及生态功能具有重要意义。该文以20世纪70年代、80年代、90年代和21世纪初4个时期的遥感数据和同期的森林资源清查样地数据为基础, 应用遥感信息模型, 估算了黑龙江长白山地区的森林生物量, 分析了该地区森林生物量的时空动态变化, 以及森林生物量随高程、坡度和坡向的变化规律。结果表明: 该地区4个时期的森林平均生物量分别为81.56、44.27、48.27和54.82 t·hm^-2。4个时期总的森林生物量分别为5.37 × 10 ⁸、2.83 × 10 ⁸、3.06 × 10 ⁸和3.46 × 10 ⁸ t。20世纪70年代到21世纪初森林平均生物量和总的森林生物量都呈现出先降低后增加的趋势, 呈先下降趋势的主要原因是20世纪70-80年代以森林采伐为主, 后增加趋势的主要原因是实施天然林保护工程起到了很大的作用。该地区4个时期森林生物量随高程、坡度和坡向都表现出一致性的变化规律, 森林生物量随高程和坡度变化都呈先增加后减少的趋势, 导致这一现象的主要原因是, 高程、坡度和坡向变化引起了局地气候条件的变化, 从而直接影响森林生长环境, 造成森林分布的变化。森林生物量在200-400 m高程所占的比例最大, 约为35%, 在坡度5°-15°所占的比例接近50%。森林生物量在南坡和西南坡所占的比例最小, 为7%; 平坡所占的比例最大, 为28%; 南坡次之, 为19%。

Temporal and spatial analysis of forest biomass in Changbai Mountains,Heilongjiang,China

Aims The objective is to obtain information on the spatial distribution and changes of forest biomass and carbon reserves to reveal patterns, discuss factors that drive change and analyze the environment of the forest. Methods Remote sensing information models were used to estimate forest biomass in Changbai Mountain of Heilongjiang based on remote sensing data and forest resource inventory data for four periods: the 1970s, 1980s, 1990s and early 21st century. Then temporal and spatial changes of forest biomass with elevation, slope and slope aspect were analyzed. Important findings Forest biomass in the four periods listed above averaged 81.56, 44.27, 48.27 and 54.82 t·hm^–2, respectively. The total forest biomass in these periods was 5.37 × 10⁸, 2.83 × 10⁸, 3.06 × 10⁸ and 3.46 × 10⁸ t, respectively. Both variables initially decreased and then increased from the 1970s to the early 21st century. This pattern of change was consistent for forest biomass changes with elevation, slope and slope aspect in the four periods. The proportion of forest biomass in elevations of 200–400 m is about 35% and in slopes of 5°–15° is close to 50%. The proportion of forest biomass was about 7%–19% at southern and southwestern aspects and about 28% in plains.