Canopy stomatal conductance following drought, disturbance, and death in an upland oak/pine forest of the new jersey pine barrens, USA.
Canopy stomatal conductance following drought, disturbance, and death in an upland oak/pine forest of the new jersey pine barrens, USA.
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在美国新泽西松树桶的高地橡木/松树林中，干旱，干旱和死亡死亡后的顶篷气孔电导。
DOI：
10.3389/fpls.2011.00015
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发表时间：
2011
影响因子：
5.6
通讯作者：
Schäfer KV
中科院分区：
文献类型：
--
作者：
Schäfer KV
气孔导度控制着森林生态系统的碳和水通量。因此，在陆面通量模式中，其精确的表征是必要的。利用树干液流尺度的冠层电导率，研究了干旱、干扰和死亡对3种栎属植物（栎栎、栎）冠层电导率的影响。velutina和Q. 2005年至2008年，在新泽西松林荒地的一个高地橡树/松树林中，冠层电导率（GC）进行了分析，在给定的光照条件下进行边界线分析和选择的最高值。回归GC与驱动力蒸汽压赤字（VPD）导致参考冠层电导在1千帕VPD（GCref）。可以预见的是，2006年的干旱导致GFref下降。Q. prinus GCref受影响最小，其次是Q. coccalus，与Q.天鹅绒具有最高的GCref减少。2007年的落叶事件导致GCref增加，原因是叶面积减少和水供应可能增加。在Q. prinus，GCref翻了两番，而Q翻了一番。velutina，在Q.球菌属。2008年的树木死亡率导致其余Q的GCref较高。prinus，而不是Q. velutina或Q.球菌属。比较光响应曲线的冠层导度（GCref）和气孔导度（GS）来自气体交换的测量表明显着差异的行为。冠层GCref在环境光照条件下不饱和，而叶片水平gS在1，200 μmol m−2 s−1时饱和。这里提出的结果强调了叶片和冠层水平的电导饱和光条件和各种干扰（干旱，落叶，死亡率）的碳和水平衡的橡树为主的森林的影响的差异响应。
Stomatal conductance controls carbon and water fluxes in forest ecosystems. Therefore, its accurate characterization in land-surface flux models is necessary. Sap-flux scaled canopy conductance was used to evaluate the effect of drought, disturbance, and mortality of three oak species (Quercus prinus, Q. velutina, and Q. coccinea) in an upland oak/pine stand in the New Jersey Pine Barrens from 2005 to 2008. Canopy conductance (GC) was analyzed by performing boundary line analysis and selecting for the highest value under a given light condition. Regressing GC with the driving force vapor pressure deficit (VPD) resulted in reference canopy conductance at 1 kPa VPD (GCref). Predictably, drought in 2006 caused GCref to decline. Q. prinus GCref was least affected, followed by Q. coccinea, with Q. velutina having the highest reductions in GCref. A defoliation event in 2007 caused GCref to increase due to reduced leaf area and a possible increase in water availability. In Q. prinus, GCref quadrupled, while doubling in Q. velutina, and increasing by 50% in Q. coccinea. Tree mortality in 2008 led to higher GCref in the remaining Q. prinus but not in Q. velutina or Q. coccinea. Comparing light response curves of canopy conductance (GCref) and stomatal conductance (gS) derived from gas-exchange measurements showed marked differences in behavior. Canopy GCref failed to saturate under ambient light conditions whereas leaf-level gS saturated at 1,200 μmol m−2 s−1. The results presented here emphasize the differential responses of leaf and canopy-level conductance to saturating light conditions and the effects of various disturbances (drought, defoliation, and mortality) on the carbon and water balance of an oak-dominated forest.
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影响因子：
1.5
作者：
CERMAK, J;DEML, M;PENKA, M
通讯作者：
PENKA, M
影响因子：
9.8
作者：
Dale, VH;Joyce, LA;Neilson, RP
通讯作者：
Neilson, RP
影响因子：
2.7
作者：
Alder, NN;Sperry, JS;Pockman, WT
通讯作者：
Pockman, WT
影响因子：
4
作者：
Ewers, B. E.;Mackay, D. S.;Samanta, S.
通讯作者：
Samanta, S.
影响因子：
6.2
作者：
GRANIER, A;LOUSTAU, D
通讯作者：
LOUSTAU, D