School of Natural Sciences, Laurentian University, Sudbury, ON, P3E 2C6, Canada.
Ecotoxicology. 2024 Dec;33(10):1145-1160. doi: 10.1007/s10646-024-02804-5. Epub 2024 Oct 6.
The manual addition of lime to soil, in addition to tree planting and fertilization have been the dominant strategy described in restoration protocols for ecosystems damaged by acid rain and metal contamination. Investigations on aerial-limed soils in inaccessible lands are limited. The objective of this study was to assess the effects of aerial liming on soil pH, organic matter, microbial biomass, and enzymatic activities, and aboveground plant population quality in metal-contaminated lands in northern Ontario, Canada. Soil samples were collected from three sites around the City of Greater Sudbury with each pair being composed of a reclaimed (areal-limed) site and an adjacent undisturbed (unlimed) area. Soil physico-chemistry, microbial biomass (assessed by Phospholipid fatty acid analysis) and enzymatic activities were analyzed. Soil pH was higher in limed sites compared to unlimed at recently restored sites (Baby Lake and Wahnapitae) but not at the oldest reclaimed site (HWY 80 N). Organic matter was higher in limed areas compared to the unlimed reference site only at most recently reclaimed site at Baby Lake. Aboveground plant population health was visibly improved in limed sites compared to unlimed areas. Metal concentrations of iron (Fe) and arsenic (As), total microbial biomasses, gram-negative bacterial, fungal, and eukaryotic biomasses were all significantly increased in the limed soils compared to the unlimed samples. The same trend was observed for the activities of three of the enzymes tested, β-N-acetylglucosaminidase (BG), aryl sulfatase (AS), and glycine aminopeptidase (GAP). Interestingly, strong positive correlations between the levels of soil organic matter, microbial biomasses, and NAGase and ALP activities were observed. Although expensive, aerial liming is effective in restoring inaccessible sites impacted by smelting operations where other methods cannot easily be used.
除了植树和施肥之外，向土壤中人工添加石灰一直是受酸雨和金属污染影响的生态系统恢复方案中占主导地位的策略。对难以进入地区的空中加石灰土壤的调查有限。本研究的目的是评估在加拿大安大略省北部受金属污染地区，空中加石灰对土壤 pH 值、有机质、微生物生物量和酶活性以及地上植物种群质量的影响。从萨德伯里市周围的三个地点采集土壤样本，每个地点由一个再开垦（加石灰）地点和一个相邻的未受干扰（未加石灰）区域组成。分析了土壤理化性质、微生物生物量（通过磷脂脂肪酸分析评估）和酶活性。与未加石灰的参考点相比，最近恢复的地点（Baby Lake 和 Wahnapitae）的石灰处理地点的土壤 pH 值更高，但在最古老的再开垦地点（HWY 80 N）则不然。与未加石灰的参考点相比，只有在最近重新开垦的 Baby Lake 地点，石灰处理区的有机质含量更高。与未加石灰区相比，石灰处理区地上植物种群的健康状况明显改善。与未加石灰的样本相比，石灰处理土壤中的铁 (Fe) 和砷 (As) 金属浓度、总微生物生物量、革兰氏阴性细菌、真菌和真核生物生物量以及三种测试酶中的三种酶（β-N-乙酰氨基葡萄糖苷酶（BG）、芳基硫酸酯酶（AS）和甘氨酸氨肽酶（GAP））的活性均显著增加。观察到相同的趋势，未加石灰样本相比，石灰处理土壤中的铁 (Fe) 和砷 (As) 金属浓度、总微生物生物量、革兰氏阴性细菌、真菌和真核生物生物量以及三种测试酶中的三种酶（β-N-乙酰氨基葡萄糖苷酶（BG）、芳基硫酸酯酶（AS）和甘氨酸氨肽酶（GAP））的活性均显著增加。观察到相同的趋势，
