Water flow through junctions in Douglas-fir roots.
Water flow through junctions in Douglas-fir roots.
复制标题
水流过花旗松根部的连接处。
DOI：
10.1111/j.1365-3040.2005.01401.x
复制
发表时间：
2006
期刊：
影响因子：
--
通讯作者：
P. Schulte
中科院分区：
文献类型：
--
作者：
P. Schulte
根是根系区水分再分配的重要管道。根系通常是高度分枝的，区域之间的水流无疑会通过单个根系之间的连接点。本研究考虑了花旗松根的连接处，考虑了水流通过木质部时所遇到的阻力。沿主根向远端流入根分支遇到的阻力比流入分支和沿沿着主根向近端（朝向植物茎）的阻力大得多。当靠近连接处的主根逐渐缩短时，分支根和沿着主根远端的流动阻力急剧增加。因此，以这种方式的流动似乎取决于根部内靠近接合处许多厘米的侧向流动，而不仅仅是接合处的直接连接内的侧向流动。这些结果表明，水力性质的路口是一个重要方面的水力再分配的水在土壤中利用通过根流。
Roots are important conduits for the redistribution of water within the rooting zone. Root systems are often highly branched, and water flow between regions undoubtedly involves passage through junctions between individual roots. This study considered junctions in the roots of Douglas-fir with regard to the resistances encountered by water flow through the xylem. Flow into the root branch distally along the main root encountered much greater resistance than flow into the branch and proximally along the main root (toward the plant stem). When the main root proximal to the junction was gradually shortened, the resistance to flow in the branch root and distally along the main root increased dramatically. Thus, flow in this manner appears to depend on lateral flow within the root over many centimetres proximal to the junction and not just within the direct connection at the junction. These results suggest that the hydraulic nature of junctions is an important aspect of hydraulic redistribution of water within the soil utilizing flow through roots.