CAJ | 학술논문

大兴安岭是我国惟一的寒温带针叶林区和高纬度多年冻土区,同时也是我国森林火灾的多发区.林火干扰作为森林生态系统稳定、可持续发展的关键影响因子,在全球气候变化的背景下显得尤为重要.2011年6—10月,在寒温带大兴安岭冻土林区未过火区、火灾后3年和8年的火烧迹地,我们利用静态箱-气相色谱法对火灾后不同年份(3a、8a)、不同程度(轻度、重度)火烧迹地土壤表面CO2通量(Rs)进行生长季原位观测,其结果表明:(1)火烧迹地Rs生长季变化呈单峰曲线(峰值出现在7月末),而未过火区Rs呈双峰曲线(峰值分别出现在7月末和8月末);(2)3a和8a火烧迹地Rs变化值分别为1.12~3.92μmol/(m2·s)和1.10~4.23μmol/(m2·s),轻度和重度火烧迹地 Rs 变化值分别为1.07~4.13μmol/(m2·s)和1.15~4.02μmol/(m2·s),而未过火区Rs变化值为0.69~3.06μmol/(m2·s);(3)通过对不同年份、不同程度火烧迹地Rs比较,得出8a>3a>未过火区、轻度>重度>未过火区的CO2通量特点;(4)所有样地Rs和0~10 cm土壤温度(T10)具有极显著的指数回归关系(P<0.01),且8a火烧迹地和重度火烧迹地Rs对T10的敏感性分别高于3a火烧迹地和轻度火烧迹地;(5)对各样地Rs与0~10 cm土壤含水率(W10)的二次方程回归初步认为,W10不是影响该区Rs的主要因素.
대흥안령시아국유일적한온대침협림구화고위도다년동토구,동시야시아국삼림화재적다발구.림화간우작위삼림생태계통은정、가지속발전적관건영향인자,재전구기후변화적배경하현득우위중요.2011년6—10월,재한온대대흥안령동토림구미과화구、화재후3년화8년적화소적지,아문이용정태상-기상색보법대화재후불동년빈(3a、8a)、불동정도(경도、중도)화소적지토양표면CO2통량(Rs)진행생장계원위관측,기결과표명:(1)화소적지Rs생장계변화정단봉곡선(봉치출현재7월말),이미과화구Rs정쌍봉곡선(봉치분별출현재7월말화8월말);(2)3a화8a화소적지Rs변화치분별위1.12~3.92μmol/(m2·s)화1.10~4.23μmol/(m2·s),경도화중도화소적지 Rs 변화치분별위1.07~4.13μmol/(m2·s)화1.15~4.02μmol/(m2·s),이미과화구Rs변화치위0.69~3.06μmol/(m2·s);(3)통과대불동년빈、불동정도화소적지Rs비교,득출8a>3a>미과화구、경도>중도>미과화구적CO2통량특점;(4)소유양지Rs화0~10 cm토양온도(T10)구유겁현저적지수회귀관계(P<0.01),차8a화소적지화중도화소적지Rs대T10적민감성분별고우3a화소적지화경도화소적지;(5)대각양지Rs여0~10 cm토양함수솔(W10)적이차방정회귀초보인위,W10불시영향해구Rs적주요인소.
Great Xing’an Mountain is China’s only cold-temperate coniferous forest area and high latitude permafrost region that experiences frequent forest fires. Forest fire is the key factor affecting the stability of forest ecosystem and sustainable development under climate change. In 2011, the static chamber method was used to measure soil surface CO2 flux (Rs) during the growing season (June to October 2011) in 2 burned sites. The sites had experienced fire at different times (3a and 8a, respectively). Within each site, measurements were taken in areas differing in fire intensity (lightly burned or severely burned). One unburned control plot was also measured. Results:1) Rs of burned plots showed a unimodal curve with maximum Rs occurring at the end of July. The unburned plot shows a bimodal curve with maxima at the end of July and August, respectively. 2) The range of Rs was 1.10-4.23μmol/(m2·s) at the 8a site and 1.12-3.92 μmol/(m2·s) at the 3a site. Rs ranged from 1.07-4.13 μmol/(m2·s) in light fire and 1.15-4.02 μmol/(m2·s) in severe fire areas, and from 0.69-3.06 μmol/(m2·s) in the unburned plot. 3) The order in measured Rs was as follows: 8a>3a>unburned. Severe fire areas had higher Rs than unburned but lower Rs than light fire. 4) A significant index regression relationship was found between Rs and soil temperature at 0-10 cm(T10) (P<0.05). 5) Regression analysis of soil water content at 0-10cm depth (W10) suggested that W10 wasn’t the main factor affecting Rs.