Brun Fernando G, Cummaudo Fabio, Olivé Irene, Vergara Juan José, Pérez-Lloréns José Lucas
1Netherlands Institute of Ecology (NIOO-KNAW), Centre for Estuarine and Marine Ecology, Korringaweg 7, 4401 NT Yerseke, The Netherlands.
3Departamento de Biología. Área de Ecología, Universidad de Cádiz, Facultad de Ciencias del Mar y Ambientales, 11510 Puerto Real, Cádiz, Spain.
Mar Biol. 2007;151(5):1917-1927. doi: 10.1007/s00227-007-0627-y. Epub 2007 Feb 8.
Disaggregating seagrass meadows and studying its components separately (clones, ramets, shoots) can provide us insights on meadow dynamics and growth patterns. The clonal growth, dependent upon clonal rules may regulate and impose constraints to plant architecture and, therefore, determine how individual clones evolve into the environment. In order to investigate the relationship between clonal growth rules and clone architecture, the belowground network architecture of single-clones of the seagrass was studied. Networks were traced in situ after washing out the overlying sediment, and network characteristics were measured using digital analysis: area covered by clone, total rhizome length, type of rhizomatic axes (main, secondary, tertiary, quaternary), number and length of the internodes, branching angles and branching frequencies. This approach revealed that is able to develop into large clones integrating up to 300 internodes, 676 cm of rhizome, 208 shoots and 4,300 cm of plant area. Internodal length depended on both, the distance to the apical shoot (time effect) and the axes type (apical dominance effect). However, average branching angle was independent of axis type (average 58.3 ± 0.75), but varied significantly depending on the distance from the apical shoot. This average branching angle allows maximize the rate of centrifugal expansion, maintaining a high density in colonized areas to produce close stands but also minimizing the investment in belowground biomass and ramets overlapping. The clonal architecture of seems to be regulated by the interaction of both, apical dominance strength and clonal integration distance. Moreover, clonal growth rules and growth pattern seem to constrain clonality through (clonal) plant architecture regulations (i.e. branching is restricted in secondary axes, similar average branching angles regardless the axes, the higher the distance to the apex the higher the number of internodes in secondary axes, shorter internodes in secondary and tertiary axes). Future research efforts should focus on how these complex relationships between apical dominance and clonal integration interact to elucidate the temporal (seasonal) and spatial scales of both processes and the outcome at the plant architectural level.
将海草草甸分解并分别研究其组成部分（克隆体、分株、嫩枝），可以让我们深入了解草甸动态和生长模式。依赖克隆规则的克隆生长可能会调节并对植物结构施加限制，从而决定单个克隆体如何在环境中演化。为了研究克隆生长规则与克隆体结构之间的关系，对海草单克隆体的地下网络结构进行了研究。在冲洗掉上层沉积物后，在原位追踪网络，并使用数字分析测量网络特征：克隆体覆盖面积、总根茎长度、根茎轴类型（主、次、三、四级）、节间数量和长度、分支角度和分支频率。这种方法表明，[海草名称]能够发育成整合多达300个节间、676厘米根茎、208个嫩枝和4300平方厘米植物面积的大型克隆体。节间长度既取决于距顶端嫩枝的距离（时间效应），也取决于轴的类型（顶端优势效应）。然而，平均分支角度与轴的类型无关（平均为58.3±0.75），但会因距顶端嫩枝的距离而有显著变化。这个平均分支角度使[海草名称]能够最大化离心扩展速率，在已定居区域保持高密度以形成紧密群落，同时也将地下生物量和分株重叠的投资降至最低。[海草名称]的克隆结构似乎受顶端优势强度和克隆整合距离两者相互作用的调节。此外，克隆生长规则和生长模式似乎通过（克隆）植物结构调节来限制克隆性（即二级轴上的分支受到限制，无论轴如何平均分支角度相似，距顶端越远二级轴上的节间数量越多，二级和三级轴上的节间较短）。未来的研究工作应集中在顶端优势和克隆整合之间的这些复杂关系如何相互作用，以阐明这两个过程的时间（季节）和空间尺度以及在植物结构层面的结果。
