ROOT DYNAMICS OF TALLGRASS PRAIRIE IN WET AND DRY YEARS
ROOT DYNAMICS OF TALLGRASS PRAIRIE IN WET AND DRY YEARS
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DOI：
10.1139/b87-105
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发表时间：
1987-04-01
期刊：
影响因子：
--
通讯作者：
SEASTEDT, TR
中科院分区：
文献类型：
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作者：
HAYES, DC;SEASTEDT, TR
本文利用根窗研究了美国堪萨斯州中北部高草大草原康扎大草原（以gerarsdiandropogon为主）在干旱年（1984年）和湿润年（1985年）的根系动态。干旱时产量和根长消失量减少，复雨时增加；然而，农作物产量仍然很低。1985年根长随着生长季节的增加而增加，而产量和消失量保持不变。土壤深度增加10厘米，对数量、生产力和分解的年度总结表明，干旱对这些变量的影响随着土壤深度的增加而降低。干年根长周转率平均为564，湿年为389%，其中0 ~ 10 cm深度差异最大（1984年为800,1985年为540%）。利用根窗观察到的生产和腐烂模式也记录在根系生物量数据中（从土壤岩心获得）。平均根系总生物量周转率为31%。未能将地下物质分类为组织类型（根茎、根）和活与死状态，导致生物量周转率的估计降低。最大可能的植物成分分离呈现了（地下）生长动态的最全面的画面。
Root dynamics were studied using root windows at Konza Prairie, a tallgrass prairie [dominated by Andropogon gerarsdii] in north central Kansas [USA] during dry (1984) and wet (1985) years. Amounts production, and disappearance of root length decreased during drought but increased when rains resumed; however, standing crop remained low. The 1985 root lengths increased throughout the growing season, while production and disappearance remained constant. Yearly summaries of amounts, productivity, and decomposition by 10-cm increments in soil depth show that the effect of drought on these variables decreased with increasing soil depth. Turnover rates of root length averaged 564 in the dry year versus 389% in the wet year, with the largest difference noted in the 0- to 10-cm depth (800 in 1984 versus 540% in 1985). Production and decay patterns observed using root windows were also noted in root biomass data (obtained from soil cores). The average total root biomass turnover rate was 31%. Failure to sort belowground materials into tissue types (rhizomes, roots) and live versus dead status results in reduced estimates of biomass turnover rates. The greatest possible separation of plant components presents the most comprehensive picture of (belowground) growth dynamics.