AM真菌对离子型稀土矿山废弃地土壤修复改良效果研究

黄金; 肖信锦; 王慧娟; 孙雪菲; 邓扬悟

doi:10.11674/zwyf.2022219

摘要:

目的研究3种AM真菌对离子型稀土废弃矿区的生态修复改良效果，为选择适宜的AM菌剂提供技术支撑。

方法试验采用盆栽方法，供试土壤采自江西省赣州市定南县某废弃的离子型稀土矿区，供试作物为黑麦草。在灭菌的土壤上，分别接种摩西斗管囊霉(Glomus mosseae，G.m)、根内根孢囊霉(Rhizophagus intraradices，R.i)、幼套球囊霉(Glomus etunicatum，G.e)，以不接种菌剂为对照，每个处理重复6次。播种催芽后的黑麦草，黑麦草生长210天，进行了8次株高和干物量监测，在黑麦草生长195天时 (第8次监测)，收获3个重复的黑麦草，植株样品用于分析地上部和根部干重、NPK含量，根际土壤样品用于分析pH、有机质、全量和速效氮磷钾含量。其余3个重复停止灌水用于干旱胁迫处理，在黑麦草生长210天时测定了植株超氧化物歧化酶(SOD)活性和脯氨酸含量。

结果与不接菌空白组相比，接种G.m、R.i、G.e处理根际土壤pH由强酸性(4.60)提高至7.62～7.90，有机质分别提升了123.9%、126.8%、105.0%；G.m处理土壤全氮、碱解氮和全磷分别提升了64.17%、59.93%和84.12%；R.i处理速效钾含量提高了73.31%。接种G.m、R.i和G.e处理的黑麦草株高分别增加了38.13%、34.53%和25.33%；接种R.i真菌的黑麦草地上部干重增加了43.73%，地下部氮、磷、钾含量分别提升了58.60%和83.27%、45.60%。干旱胁迫4天后，G.m、Ri、G.e 3种AM真菌SOD活性分别提高了7.35%、15.94%和4.68%，脯氨酸含量分别提高了34.94%、36.66%和16.87%。

结论在离子型稀土废弃矿区土壤上接种这3种AM真菌均能有效侵染黑麦草根系，提高植株的耐旱性，有利于植株产生更多的SOD和脯氨酸，以提高抗干旱胁迫能力。接种AM真菌可显著提高离子型稀土废弃地黑麦草根际土壤pH，提高土壤有机质、全氮、全磷和速效氮、钾含量，显著增加植株株高和地上及地下部干物质累积量。因此，接种AM真菌有利于提高离子型稀土废弃矿区的生态修复效果，尤其是G.m和R.i两种真菌有非常可期的推广前景。

Abstract:

Objectives We studied the ecological restoration effect of three kinds of AM fungi on abandoned ionic rare earth mining areas, to provide technical support for the efficient remediation and cultivation of the abandoned mining land.

Methods The experiment was carried out by pot culture and the test crop was ryegrass. The test soil was collected from a waste mining area in Dingnan County of Ganzhou City, Jiangxi Province. The soil was sterilized, then inoculated with Glomus mosseae (G.m), Rhizophagus intraradices (R.i) and Glomus etunicatum (G.e), respectively, and the soil without inoculation was used as the blank group, and each treatment was repeated 6 times. Plant height was measured 8 times since the 10th day of ryegrass growth. At the 8th measurement (195 days growth), three pots of ryegrass plants were harvested for aboveground and root dry weight and NPK content measurement, and rhizosphere soil samples were collected to analyze pH, organic matter, total and available NPK contents. The remaining three pots were not watered for drought stress treatment, and the plant superoxide dismutase (SOD) activity and proline content were determined on the 210 days of growth.

Results Compared with the control, G.m, R.i and G.e inoculation increased rhizosphere soil pH from strong acid (4.60) to 7.62–7.90, organic matter by 123.9%, 126.8% and 105.0%, and plant height by 38.13%, 34.53% and 25.33% respectively. Compared to other treatments, G.m inoculation increased total N, available N and total P in rhizosphere soil by 64.17%, 59.93% and 84.12%, respectively. Compared to other treatments, R.i inoculation increased available K by 73.31%, aboveground dry weight of ryegrass by 43.73%, and root N, P and K content by 58.60%, 83.27% and 45.60%, respectively. After 4 days of drought stress, plant SOD activity increased by 7.35%, 15.94% and 4.68%, and proline content increased by 34.94%, 36.66% and 16.87% under G.m, Ri and G.e., respectively.

Conclusions AM fungi inoculation significantly increased rhizosphere soil pH and organic matter, and nutrient content to different extent, and significantly increased plant growth and dry matter accumulation in above and below ground. AM fungi inoculation also showed signs of increasing ryegrass drought resistance at the late growing stage. Therefore, AM fungi inoculation is beneficial for the ecological restoration of waste mining areas.

AM真菌对离子型稀土矿山废弃地土壤修复改良效果研究

Effect of AM fungi on soil remediation and improvement of abandoned ionic rare earth mining area