农业工程学报
農業工程學報
농업공정학보
2015年
1期
255-263
,共9页
李卫朋%孙建%沙玉坤%程根伟
李衛朋%孫建%沙玉坤%程根偉
리위붕%손건%사옥곤%정근위
土壤%碳%温度%排放速率%气候情景%亚高山
土壤%碳%溫度%排放速率%氣候情景%亞高山
토양%탄%온도%배방속솔%기후정경%아고산
soils%carbon%temperature%emission rate%climate scenarios%sub-alpine
为进一步厘定西南地区亚高山典型林区土壤碳（carbon，C）排放的主控因素，更精确估算土壤C排放，该文以贡嘎山峨眉冷杉林为研究对象，利用Li-6400-09土壤呼吸室，采集了2008—2009年土壤CO2排放速率及相应环境要素数据。结果表明，成熟林与中龄林区土壤储量分别为291.0、63.8 t C/hm2。成熟林与中龄林全年土壤C排放速率整体变化态势基本一致。其中中龄林土壤C排放速率日均最大值、最小值与平均值分别为34.53、6.96、16.26 kg C/(hm2·d)。成熟林土壤C排放速率日均值的最大值、最小值与平均值分别为55.34、9.50、24.57 kg C/(hm2·d)。土壤C排放速率日均值与5 cm土壤温度表现的相关性最高（r 成熟=r 中龄=0.73，P<0.05）且二者存在指数关系（R2成熟=0.60，R2中龄=0.56）。土壤温度是影响该区域土壤C排放变化的主要环境驱动因子。在IPCC不同气候情景下（B1，A1B和A2），成熟林土壤C排放量将比基准情景分别高出15%、25%和31%；中龄林土壤C排放量将比基准情景高13%、21%和27%。该研究可为变化环境下中国西南山区碳平衡估算提供数据基础和参考依据。
為進一步釐定西南地區亞高山典型林區土壤碳（carbon，C）排放的主控因素，更精確估算土壤C排放，該文以貢嘎山峨眉冷杉林為研究對象，利用Li-6400-09土壤呼吸室，採集瞭2008—2009年土壤CO2排放速率及相應環境要素數據。結果錶明，成熟林與中齡林區土壤儲量分彆為291.0、63.8 t C/hm2。成熟林與中齡林全年土壤C排放速率整體變化態勢基本一緻。其中中齡林土壤C排放速率日均最大值、最小值與平均值分彆為34.53、6.96、16.26 kg C/(hm2·d)。成熟林土壤C排放速率日均值的最大值、最小值與平均值分彆為55.34、9.50、24.57 kg C/(hm2·d)。土壤C排放速率日均值與5 cm土壤溫度錶現的相關性最高（r 成熟=r 中齡=0.73，P<0.05）且二者存在指數關繫（R2成熟=0.60，R2中齡=0.56）。土壤溫度是影響該區域土壤C排放變化的主要環境驅動因子。在IPCC不同氣候情景下（B1，A1B和A2），成熟林土壤C排放量將比基準情景分彆高齣15%、25%和31%；中齡林土壤C排放量將比基準情景高13%、21%和27%。該研究可為變化環境下中國西南山區碳平衡估算提供數據基礎和參攷依據。
위진일보전정서남지구아고산전형림구토양탄（carbon，C）배방적주공인소，경정학고산토양C배방，해문이공알산아미랭삼림위연구대상，이용Li-6400-09토양호흡실，채집료2008—2009년토양CO2배방속솔급상응배경요소수거。결과표명，성숙림여중령림구토양저량분별위291.0、63.8 t C/hm2。성숙림여중령림전년토양C배방속솔정체변화태세기본일치。기중중령림토양C배방속솔일균최대치、최소치여평균치분별위34.53、6.96、16.26 kg C/(hm2·d)。성숙림토양C배방속솔일균치적최대치、최소치여평균치분별위55.34、9.50、24.57 kg C/(hm2·d)。토양C배방속솔일균치여5 cm토양온도표현적상관성최고（r 성숙=r 중령=0.73，P<0.05）차이자존재지수관계（R2성숙=0.60，R2중령=0.56）。토양온도시영향해구역토양C배방변화적주요배경구동인자。재IPCC불동기후정경하（B1，A1B화A2），성숙림토양C배방량장비기준정경분별고출15%、25%화31%；중령림토양C배방량장비기준정경고13%、21%화27%。해연구가위변화배경하중국서남산구탄평형고산제공수거기출화삼고의거。
Numerous results of carbon (C) emission of the subalpine dark conifer forest showed more or less differences for the great and complicated environmental temporal-spatial variation in the Gongga Mountain region in Southwestern China. For a more exact estimation of soil C emission in the subalpine forest and a more clear understanding of its impacting factors in the Mount Gongga, with the Li-6400-09 chamber, the soil CO2 emission and the main environment factors of the Abies fabri forests were studied. The results showed soil C storage (291.0 t/hm2, 49.8%of the forest ecosystem) in the mature Abies fabri forest is higher than that (63.8 t/hm2, 30.7%of the forest ecosystem) in middle-aged Abies fabri forest, which indicated the effects of stand age on soil C storage. Overall, the annual variation of the soil C emission rate in the mature Abies fabri forest showed a similar tendency as that in the middle-aged Abies fabri forest. For both of the mature and middle-aged Abies fabric forests, the monthly soil C emission rate in the growing season (May to October) is much higher than that in the non-growing season (November to the next April), and the maximum in summer is 5~6 times as large as that of the minimum in winter;while the soil C emission rate each month in the mature Abies fabri forest is on average 1.5 times as large as that in the middle-aged Abies fabri forest. The soil temperature, soil moisture and monthly soil CO2 emission rate generally fluctuate in synchrony under the warm and humid climate during growing season. The peak of monthly soil CO2 emission rate in the middle-aged Abies fabri forest, 34.53 kg C/(hm2·d), occures in July (the warmest and the most humid month for both of the forest soils in middle-aged and mature Abies fabri forest), while the valley, 6.96 kg C/(hm2·d), appears in February (the coldest and driest month for the forest soils in middle-aged Abies fabri), with an average of 16.26 kg C/(hm2·d) and a variation coefficient of 0.54. The maximum of monthly soil CO2 emission rate in the mature Abies fabri forest, 55.34 kg C/(hm2·d), delays one month to August, and there are two small peaks in May and December, respectively;while the minimum, 9.50 kg C/(hm2·d), delays to January, later than December that is the driest month for the mature Abies fabri forest soil, and earlier than March, the coldest month. The soil C emission rate in the mature Abies fabri forest has an average of 24.57 kg C/(hm2·d) and a variation coefficient of 0.61, which implies the mature Abies fabri forest ecosystem has more self-adjusting function. The daily average soil CO2 emission rate has more obvious correlation with soil temperature in 5 cm depth (the representative layer for the microbial activity and upper soil average heat condition) rather than air temperature, relative humidity, precipitation, and photosynthetically active radiation (PAR) in both the mature and middle-aged Abies fabri forests (r=0.73, P<0.05;the two forests are the same), and the fitted curves showed their exponential relationships (R2=0.60 for the mature forest and R2=0.56 for the middle-aged forest). In the subalpine cold-humid condition, without the high temperature inhibition, the soil moisture (monthly variation ranged from 14%to 30%) can hardly become the limiting factor, while the soil temperature plays a key role on soil C emission. Under the typical Intergovernmental Panel on Climate Change (IPCC) series of emission scenarios (SRES), i.e., B1, A1B and A2, the soil C emissions are expected to be increased by 15%, 25%and 31%respectively from the mature Abies fabri forest soil, and by 13%, 21%and 17%respectively from the middle-aged Abies fabri forest soil. It indicates that the stand age should be attached more importance in the C emission investigation and monitoring. The research provides basic data and references for the C balance estimation in the region under changing environment.
