Soil compaction effects on water status of ponderosa pine assessed through 13C/12C composition.
Soil compaction effects on water status of ponderosa pine assessed through 13C/12C composition.
复制标题
通过 13C/12C 成分评估土壤压实对黄松水分状况的影响。
DOI：
10.1093/treephys/22.7.459
复制
发表时间：
2002
期刊：
影响因子：
4
通讯作者：
W. Horwath
中科院分区：
文献类型：
--
作者：
G. Gomez;M. Singer;R. Powers;W. Horwath
土壤压实是由于使用重型设备和场地整备而导致的森林重建做法的副作用。土壤压实通常会改变土壤性质，导致植物可用水的变化。利用压力室方法评估植物水分胁迫有两个缺点：(1)测量结果不完整；(2)该方法难以广泛应用于确定季节性土壤水分状况。我们评估了叶片碳同位素组成(Delta13C)，作为评估土壤紧实对黄皮松幼树水分状况和生长的影响的一种手段。黄瓜属植物。EX法律)横跨一系列土壤纹理。叶片纤维素中的Delta13C与整个叶片组织中的Delta13C高度相关。生长在非压实壤土(NC)或粘土上的树木，其整个组织和纤维素(综纤维素)中的叶片Delta13C比在压实(SC)壤土或粘土上生长的树木低1.0‰。土壤压实对生长在砂壤土上的树木叶片Delta13C的影响相反，表明压实增加了该土壤类型的水分有效性。树木对压实的反应也因土壤质地不同而不同，壤土、粘土和砂壤土的压实对树木生长的影响分别为无影响、负影响和正效应。土壤质地的13C特征与树木生长之间存在显著的相关性。叶片Delta13C趋势与中午茎水势呈正相关。我们的结论是，叶片delta13C可以用来衡量回溯水分状况，并评估立地整地对树木生长的影响。叶片Delta13C方法的优点是它提供了对不同年龄叶片过去水分状况的综合评估。
Soil compaction is a side effect of forest reestablishment practices resulting from use of heavy equipment and site preparation. Soil compaction often alters soil properties resulting in changes in plant-available water. The use of pressure chamber methods to assess plant water stress has two drawbacks: (1) the measurements are not integrative; and (2) the method is difficult to apply extensively to establish seasonal soil water status. We evaluated leaf carbon isotopic composition (delta13C) as a means of assessing effects of soil compaction on water status and growth of young ponderosa pine (Pinus ponderosa var. ponderosa Dougl. ex Laws) stands across a range of soil textures. Leaf delta13C in cellulose and whole foliar tissue were highly correlated. Leaf delta13C in both whole tissue and cellulose (holocellulose) was up to 1.0 per thousand lower in trees growing in non-compacted (NC) loam or clay soils than in compacted (SC) loam or clay soils. Soil compaction had the opposite effect on leaf delta13C in trees growing on sandy loam soil, indicating that compaction increased water availability in this soil type. Tree growth response to compaction also varied with soil texture, with no effect, a negative effect and a positive effect as a result of compaction of loam, clay and sandy loam soils, respectively. There was a significant correlation between 13C signature and tree growth along the range of soil textures. Leaf delta13C trends were correlated with midday stem water potentials. We conclude that leaf delta13C can be used to measure retrospective water status and to assess the impact of site preparation on tree growth. The advantage of the leaf delta13C approach is that it provides an integrative assessment of past water status in different aged leaves.