Radial growth rate through successive cambia in <i>Haloxylon ammodendron </i>(Chenopodiaceae) from the Gurbantünggüt Desert, Northwestern China, determined by a series of radiocarbon dating

• DOI: 10.2343/geochemj.2.0328
• Publication Date: 2015-02-04T22:02:18Z
• Authors: Junfeng Li; Hideki Wada; Hiroyuki Matsuzaki
• Keywords: Haloxylon ammodendron

It is known that Haloxylon has successive cambia and its radial growth rate not clear as indicated by the fact annual boundary cannot be determined dendrochronological approach. Radial increment through (RISC) layers possess similar morphological feature compared to rings megascopic cross sectional observations. Previous studies have demonstrated methods applied some species cambia. The objective of present study clarify RISC layer in ammodendron a series radiocarbon dating. Two H. specimens (S1 S2) were collected from southern edge Gurbantünggüt Desert Northwestern China. Radiocarbon measurements revealed numbers 2.98 ± 0.51 (S1) 3.65 0.53 (S2). Linear regression shows strong relationship between period (x) accumulation (y): y = 1.52x + 0.76 (R2 0.96, P < 0.001) for S1 1.70x 4.49 0.94, S2, respectively. Anatomical observations on using scanning electron microscope (SEM) image showed that: (1) early wood late or differentiated; (2) axial vessel groups (about 2-10 vessels) are often distributed bark-side; (3) sclerenchyma cells junctions tightly adhered at outside each layer. These observed features completely different those ring morphologies. We tentatively hypothesize these due formation multiple within one growing season order aid water storage stem survive harsh habitat conditions. This research will help further knowledge physiological ecophysiological researches other species.