东北林业大学学报
東北林業大學學報
동북임업대학학보
JOURNAL OF NORTHEAST FORESTRY UNIVERSITY
2014年
1期
80-85
,共6页
高琛%杨新兵%鲁绍伟%李少宁%陈波%潘青华%马成东
高琛%楊新兵%魯紹偉%李少寧%陳波%潘青華%馬成東
고침%양신병%로소위%리소저%진파%반청화%마성동
北京沙地%107欧美杨%同位素%人工林生态系统%水分利用策略
北京沙地%107歐美楊%同位素%人工林生態繫統%水分利用策略
북경사지%107구미양%동위소%인공림생태계통%수분이용책략
Beijing sandy area%107 Populus×euramericanacv%Isotope%Plantation ecosystem%Water utilization strategy
以北京沙地107欧美杨人工林为研究对象,采用DELTA V Advantage同位素比率质谱仪测定杨树茎木质部δ( D)、δ(18 O)稳定性同位素值,结合自动气象站( HOBO)连续观测土壤含水量( SWC)和降水量,利用三源线性混合模型,揭示杨树人工林生态系统水分利用策略。结果表明:(1)夏季土壤含水量均高于秋季,降水在转化为土壤水和地下水的过程中发生同位素分馏。(2)夏秋两季土壤水δ(D)、δ(18O)同位素与土层深度之间均存在显著二次多项式关系,R值均在0.8341以上,表现为越接近土壤表层,土壤水δ(D)、δ(18O)同位素越偏正。(3)秋季>100~120 cm土层为土壤水δ( D)、δ(18 O)同位素的显著变化层,而夏季没有明显变化层。土壤水稳定性随土层深度的增加而升高。(4)夏季杨树根系主要吸收140 cm以下土壤水和地下水,秋季不仅吸收140 cm以下土壤水和地下水,对浅层土壤水也有少量吸收。可见,在土质疏松和孔隙度大的地区,杨树根系再生能力强且具有明显的趋水性。
以北京沙地107歐美楊人工林為研究對象,採用DELTA V Advantage同位素比率質譜儀測定楊樹莖木質部δ( D)、δ(18 O)穩定性同位素值,結閤自動氣象站( HOBO)連續觀測土壤含水量( SWC)和降水量,利用三源線性混閤模型,揭示楊樹人工林生態繫統水分利用策略。結果錶明:(1)夏季土壤含水量均高于鞦季,降水在轉化為土壤水和地下水的過程中髮生同位素分餾。(2)夏鞦兩季土壤水δ(D)、δ(18O)同位素與土層深度之間均存在顯著二次多項式關繫,R值均在0.8341以上,錶現為越接近土壤錶層,土壤水δ(D)、δ(18O)同位素越偏正。(3)鞦季>100~120 cm土層為土壤水δ( D)、δ(18 O)同位素的顯著變化層,而夏季沒有明顯變化層。土壤水穩定性隨土層深度的增加而升高。(4)夏季楊樹根繫主要吸收140 cm以下土壤水和地下水,鞦季不僅吸收140 cm以下土壤水和地下水,對淺層土壤水也有少量吸收。可見,在土質疏鬆和孔隙度大的地區,楊樹根繫再生能力彊且具有明顯的趨水性。
이북경사지107구미양인공림위연구대상,채용DELTA V Advantage동위소비솔질보의측정양수경목질부δ( D)、δ(18 O)은정성동위소치,결합자동기상참( HOBO)련속관측토양함수량( SWC)화강수량,이용삼원선성혼합모형,게시양수인공림생태계통수분이용책략。결과표명:(1)하계토양함수량균고우추계,강수재전화위토양수화지하수적과정중발생동위소분류。(2)하추량계토양수δ(D)、δ(18O)동위소여토층심도지간균존재현저이차다항식관계,R치균재0.8341이상,표현위월접근토양표층,토양수δ(D)、δ(18O)동위소월편정。(3)추계>100~120 cm토층위토양수δ( D)、δ(18 O)동위소적현저변화층,이하계몰유명현변화층。토양수은정성수토층심도적증가이승고。(4)하계양수근계주요흡수140 cm이하토양수화지하수,추계불부흡수140 cm이하토양수화지하수,대천층토양수야유소량흡수。가견,재토질소송화공극도대적지구,양수근계재생능력강차구유명현적추수성。
With 107 Populus×euramericanacv plantation in Beijing sandy area, we measured the stableδD andδ18 O isotope value of poplar stem and xylem by using the DELTA V Advantage Isotope Ratio Mass Spectrometer and observed the soil water content (SWC) and rainfall continuously by HOBO.We revealed the strategies on water utilization of polar plantation eco-system with three source linear mixed model.SWC in summer is higher than that in autumn and isotope is fractionated when rainfall is transferring into soil water and underground water .There is an obviousquadratic polynomial relations be-tween soil depth and theδD ,δ18 O isotope of soil water in summer and autumn with R>0.834 1, that is, theδD andδ18 O isotope of soil water tend to be more positive when it is nearer the top soil.In autumn, theδD andδ18 O isotope of soil wa-ter vary obviously in 100-120 cm soil layer, but there is no difference in summer.The stability of soil water increases with the depth increasing of soil layer.In summer, the root of poplar mainly absorbs the soil water and underground water below 140 cm, and it also absorbs a little water in shallow soil layer in autumn.Therefore, the poplar root system has the abilities of regeneration and hydrotaxis in the areas with loose soil and large soil porosity .