Hu Juan, Zhou Daowei
State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun China.
Jilin Provincial Key Laboratory of Grassland Farming Changchun China.
Ecol Evol. 2024 Aug 13;14(8):e70072. doi: 10.1002/ece3.70072. eCollection 2024 Aug.
Trace elements are the essential mineral nutrients in grassland, however, we still know little about the distributions of trace elements in grassland with long-term grazing exclusion. The contents, stocks, and proportions of iron (Fe), aluminum (Al), manganese (Mn), and boron (B) in green plant-litter-root-soil were evaluated by enclosing for 18, and 39 years inside the fence (F18 and F39) and grazing outside the fence (F0) in Inner Mongolia grassland. The results showed that F18 and F39 decreased the stocks of Fe, Al, and Mn in green plant and root compared to F0 ( < .05), while increased the stocks of them in litter ( < .05). The stock of Fe, Al, and Mn in green plant at F39 was 28.6%, 13.9%, and 39.2% higher than that at F18. The stocks of four trace elements in first layer litter at F39 were increased by 12.7%-52.2% compared to F18, whereas the stocks of them in third layer litter were decreased by 32.2%-42.5%. The F18 obviously increased the stocks of Fe and Mn in soil, especially B ( < .05). While the stocks of these trace elements in soil at F39 were 9.1%-28.0% lower than that at F18, especially B ( < .05). In conclusion, the trace elements were mainly shifted from green plant and root to soil and third layer litter with 18-year grazing exclusion. Compared to 18-year grazing exclusion, the trace elements were shifted from third layer litter and soil to root with 39-year grazing exclusion.
微量元素是草原中必需的矿物质养分，然而，我们对长期禁牧草原中微量元素的分布仍知之甚少。通过在内蒙古草原围栏内封闭18年和39年（F18和F39）以及围栏外放牧（F0），评估了绿色植物-凋落物-根系-土壤中铁（Fe）、铝（Al）、锰（Mn）和硼（B）的含量、储量及比例。结果表明，与F0相比，F18和F39降低了绿色植物和根系中Fe、Al和Mn的储量（P<0.05），而增加了它们在凋落物中的储量（P<0.05）。F39时绿色植物中Fe、Al和Mn的储量分别比F18时高28.6%、13.9%和39.2%。F39时第一层凋落物中四种微量元素的储量比F18时增加了12.7%-52.2%，而第三层凋落物中则减少了32.2%-42.5%。F18显著增加了土壤中Fe和Mn的储量，尤其是B（P<0.05）。而F39时土壤中这些微量元素的储量比F18时低9.1%-28.0%，尤其是B（P<0.05）。总之，禁牧18年时，微量元素主要从绿色植物和根系转移到土壤和第三层凋落物中。与禁牧18年相比，禁牧39年时，微量元素从第三层凋落物和土壤转移到了根系中。
