| 摘要: |
| 锰是一种植物必需元素，但过量会导致植株死亡。本研究在部分白骨壤疑似出现锰毒症状的广西北海红树林湿地保护区内设立9个样方，测定样方内白骨壤根系生理生化指标和土壤理化因子；通过方差分析、Pearson相关分析和逐步回归分析等方法分析各因子对白骨壤根系锰含量和土壤Mn2+含量的影响，从而探究白骨壤生长衰弱的原因。结果显示，根系锰含量和土壤Mn2+含量与多种根系生理生化指标、土壤理化因子具显著相关性。多元逐步回归分析表明：对根系锰含量影响显著的是根系活力、须根鲜重、土壤电导率、土壤含水量，以及须根鲜重、土壤电导率分别与土壤含水量的交互项；对土壤Mn2+含量影响显著的是枯枝率、土壤砂、粉砂、潮位，以及土壤砂和潮位的交互项。研究地根系锰含量范围为74.60-256.05 mg/kg，远小于深圳生长良好的白骨壤根系锰含量（700 mg/kg），因此该地白骨壤生长衰弱不是由锰过量直接导致的，白骨壤枯梢原因需要进一步研究。 |
| 关键词: 白骨壤，锰积累，影响因素，根系，红树林 |
| DOI： |
| 投稿时间：2024-04-26修订日期：2024-10-21 |
| 基金项目:国家自然科学基金项目(32060282和U21A2022),国家自然科学基金项目（面上项目，重点项目，重大项目）和自治区直属公益性科研院所基本科研业务费项目（GMRC-202403） |
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| Accumulation and Influencing Factors of Mn Content in the Roots of Avicennia Marina |
|
XUE Yunhong, LIU Wenai, FANG Chao
|
| (Guangxi Academy of Marine Sciences （Guangxi Mangrove Research Center）) |
| Abstract: |
| Manganese is an essential element for plants, but an excessive amount can cause plant death. In this study, nine sample plots were set up in the Guangxi Beihai coastal national wetland park, where suspected Mn toxicity symptoms of Avicennia marina had already appeared, to investigate root manganese content, and to understand root physiological and biochemical index and soil physicochemical factors. ANOVA, pearson correlation analysis and stepwise regression analysis were used to understand the effects of various factors on the Mn content in the root system, so as to investigate the reasons for the weakened growth of Avicennia. The results showed that root Mn content and soil Mn2+ content were significantly correlated with various root physiological and biochemical index and soil physicochemical factors. Stepwise regression analyses showed that root activity, root fresh weight, soil electrical conductivity, soil water content, and the interaction of root fresh weight with electrical conductivity and water content significantly affected root Mn content; dieback rate, soil sand and silt content, tidal level, and the interaction of soil sand and tidal level significantly affected soil Mn2+ content. The manganese content in Avicennia roots of the study site was 74.60-256.05 mg/kg, which was much smaller than that of the well-grown Avicennia in Shenzhen(700 mg/kg). The growth decline of Avicennia was not directly caused by excessive manganese, and the cause of Avicennia dieback should be further investigated. |
| Key words: Avicennia marina Mn accumulation influence factors root mangrove |
