不同覆土处理对青海木里煤田排土场渣山表层土壤 基质特征的影响

Accelerating the establishment of artificial vegetation through soil covering measures is a key technical issue for vegetation restoration in alpine mining areas. In this paper, by establishing vegetation restoration experimental plots in the dump of the Jiangcang mining area in the Muli coalfield in Qinghai, the effects of different soil covering treatments such as 0 cm of soil covering (control), 5 cm of soil covering, 10 cm of soil covering, and 15 cm of soil covering on the characteristics of the surface soil matrix of the slag mountain in the alpine mining area dump were compared, providing a reference for soil reconstruction in alpine mining areas. The results showed that soil covering can adjust the bulk density of the surface soil matrix, which is beneficial for forming the soil physical structure for vegetation growth. Soil covering increased the total nitrogen content and the supply of available nutrients in the soil matrix. With the extension of the treatment time (from 2016 to 2018), the effect of soil covering became more and more obvious. The available nitrogen contents of different soil covering treatments increased from 40.3 ± 5.13 mg·kg⁻¹, 85 ± 14.9 mg·kg⁻¹, and 57.3 ± 11.1 mg·kg⁻¹ in 2016 to 101.0 ± 8.54 mg·kg⁻¹, 192.0 ± 33.6 mg·kg⁻¹, and 168.7 ± 17.0 mg·kg⁻¹ in 2017, respectively. The available nutrients in the soil covering treatment generally showed a trend of first increasing and then decreasing, reaching the maximum value of available nutrients in the second year, and the change range of the available phosphorus content with 10 cm of soil covering was relatively the largest. The total nitrogen content of the surface soil matrix was extremely significantly positively correlated with the available nitrogen and available potassium contents (r = 0.905, r = 0.733; P < 0.01), and extremely significantly negatively correlated with pH (r = 0.753, P < 0.01). 10 cm of soil covering can be used as an ideal soil covering measure for soil reconstruction in alpine mining areas.

通过覆土措施加速人工植被建植是高寒矿区植被恢复的关键技术问题。本文通过在青海木里煤田江仓矿区排土场建立植被恢复试验小区，比较覆土0cm(对照)、覆土5cm、覆土10cm 和覆土15cm 等不同覆土处理对高寒矿区排土场渣山表层土壤基质特征的影响，为高寒矿区土壤重构提供参考。结果表明，覆土可调节表层土壤基质容重，有利于形成植被生长的土壤物理结构。覆土增加了土壤基质中的全氮含量和速效养分的供给，随着处理时间的延长，（2016-2018年），覆 土 效 果 愈 来 愈 明 显。不 同 覆 土 处 理 速 效 氮 含 量 分 别 由2016年 的 40.3±5.13mg·kg-1，85±14.9mg·kg-1，57.3±11.1mg·kg-1增加至2017年 101.0±8.54mg·kg-1，192.0±33.6mg·kg-1，168.7±17.0mg·kg-1。覆土处理的速效养分出现先上升后下降的总体变化趋势，第二年达到速效养分最大值，覆土10cm 速效磷含量变化幅度相对最大。表层土壤基质全氮含量与速效氮、速效钾含量呈极显著正相关（r=0.905，r=0.733；P＜0.01）,与pH 呈极显著负相，（r=0.753,P＜0.01）。覆土10cm 可作为高寒矿区土壤重构理想的覆土措施.