保水剂与有机肥配施对铁尾矿理化性质的改良作用

为了分析保水剂与有机肥配合施加对铁尾矿理化性质的影响,确定适宜尾矿改良的保水剂与有机肥最优配比,在迁安首钢所辖的铁尾矿区内,布设保水剂与有机肥2因素4水平的野外小区试验,并测定试验小区铁尾矿容重、孔隙度及持水量和pH、有机质、氮、磷、钾含量等理化性质,分析有机肥和保水剂对尾矿改良的作用;同时在小区内播种紫苜蓿和紫穗槐两种植物,测其生物量,验证改良效果.保水剂水平为(L·m^-3):0(B₀)、10(B₁)、50(B₂)、100(B₃);有机肥水平为(kg·m^-2):0(N₀)、2.25(N₁)、11.24(N₂)、22.49(N₃).结果表明:不同配比处理对尾矿理化性质的改良作用主要体现在0～20 cm表层尾矿,各指标均在0～20 cm层与对照(CK)差异显著.有机肥对尾矿理化性质的改良作用优于保水剂.在0～20 cm层,保水剂单因素的所有处理尾矿容重、非毛管孔隙度、有机质、速效磷和速效钾含量均与CK无显著差异,而单独施加有机肥B₀N₂、B₀N₃处理的上述指标均与CK差异显著.保水剂与有机肥二者配合施加优于保水剂或有机肥单独添加的改良效果.0～20 cm层各项指标均在配施处理B₃N₃下达到最佳,且均与CK达到显著差异.综合考虑,B₃N₃可以作为尾矿改良的保水剂与有机肥最优配比.

Effects of combined application of water retention agent and organic fertilizer on physico-chemical properties of iron tailings.

In order to analyze the effects of combined application of water retention agent and orga-nic fertilizer on physico-chemical properties of iron tailings and to find the optimal proportion of water retention agent and organic fertilizer for the improvement of iron tailings, the experimental plots of the combination trials with 2 factors in 4 levels were designed in the iron tailings of Qian’an Shougang through investigating some indexes of physico-chemical properties such as bulk density, moisture capacity, porosity, pH and the contents of organic matter, nitrogen, phosphorus and potas-sium. The biomasses of Medicago sativa and Amorpha fruticosa planted in the experimental plots were measured to verify the improvement effects. 4 levels of super absorbent polymers (L·m^-3) used in treatments were 0 (B₀), 10 (B₁), 50 (B₂), 100 (B₃), and 4 levels of organic fertilizer (kg·m^-2) were 0(N₀), 2.25 (N₁), 11.24 (N₂), 22.49 (N₃). The improving effects of different treatments on physico-chemical properties of iron tailings were mainly reflected in the surface layer of 0-20 cm. All the tested indexes were significantly different from control (CK) in the layer of 0-20 cm. The improvement effects of organic fertilizer on physical and chemical properties of iron tai-lings were better than that of water retention agent. In the 0-20 cm layer, the bulk density, non-capillary porosity, organic matter, rapidly available phosphorus, and available potassium under all treatments of adding water retention agent individually were not significantly different from the CK, while significant difference was observed when the organic fertilizer was solely applied in B₀N₂ and B₀N₃ treatments. The improvement synergy effect of organic fertilizer and water retention agent was better than that of organic fertilizer or water retention agent, respectively. In 0-20 cm layer, all the indexes obtained from treatment B₃N₃ performed best and were significantly different from the CK, which was the optimum for the improvement of iron tailings.