多花黑麦草草地对奶牛场沼液养分消纳能力的研究

Nutrient assimilating capacity of Lolium multiflorum pasture for dairy farm biogas slurry

集约化奶牛养殖厂产生的大量沼液如不加以合理利用,将对养殖场周边环境造成严重的环境危害。本试验采用沟施方式,设置5个沼液施肥水平,即0,1.2×105,2.4×105,3.6×105,4.8×105 kg/hm2,研究了黑麦草草地对奶牛场沼液养分的消纳能力。结果表明,随施肥梯度的增加,黑麦草干物质收获量显著增加,地上部植株N,P,K三元素的含量增加,当施用量超过3.6×105 kg/hm2时干物质增加幅度变缓,养分含量增幅下降。当沼液施用浓度低于3.6×105 kg/hm2时,土壤中N,P,K三元素累积量在不同施肥梯度间差异不显著;当沼液浓度为4.8×105kg/hm2时,土壤中三元素累积量均大幅度上升。综合分析认为,沟施沼液条件下,沼液用量不超过3.6×105kg/hm2,即可满足黑麦草生长的需要,且对环境负荷相对较小。

To protect the ecological environment and decontaminate wastewater {rom domestic animals in the Three Gorges Reservoir Area, dairy farm biogas liquid assimilative capacity of Italian ryegrass （Loliurn multi- JTorum） was studied by a furrow application method using five biogas liquid application levels （0, 1.2 × 10s, 2.4X10s, 3.6X10s, 4.8×10s kg/ha）. The dry matter yields, N, P, and K consumption of Italian ryegrass increased significantly with increasing application rate. However, the increase of dry matter yield slowed, and the N, P and K consumptions were reduced significantly when the application rate reached 3.6 × 10s kg/ha. In soil, the contents of N, P, and K did not change significantly when the application rate was less than 3.6 ×l0s kg/ha, but at 4.8X 10s kg/ha there was a significant increase of N and P contents. Overall, the Italian ryegrass plants could consume 3.6× l0s kg/ha maximum under furrow application, and it was concluded that the 3.6× 105 kg/ha application rate could meet plant requirements and be relatively safe for the environment.