塑料大棚在苜蓿干燥中的应用研究

以黄淮海地区紫花苜蓿为研究材料,利用塑料大棚进行苜蓿干燥试验研究,探讨其干燥效果及其可利用性。结果表明,1)塑料大棚内的气温变化范围为27~46℃,比大棚外高5~13℃,空气相对湿度变化范围为16%~52%,比大棚外低9~24个百分点,其对加快苜蓿干燥和营养保存具有明显的促进作用,适合进行苜蓿干草调制,而且可在一定程度上降低夜间湿度过大及阴雨天气对干燥的不利影响,进而生产出优质的苜蓿干草;2)苜蓿在压扁刈割后置于塑料大棚内干燥效果显著,只需32 h即可将含水量降至15%以下,干燥时间比对照组缩短了48 h,而且营养物质保存较好,CP和TDN含量为18.64%和66.72%,分别比对照组提高了20.73%和11.00%,NDF和ADF含量为41.89%和29.65%,分别比对照组降低了12.60%和17.87%。因此,塑料大棚干燥是一种较为理想的调制优质苜蓿干草的方法,适合在降雨量偏多地区、苜蓿种植面积相对较小的农户中推广应用。

Plastic covered sheds for drying alfalfa

Alfalfa (cv.Suntoryin)was dried in clear plastic covered sheds to investigate the benefits for alfalfa hay production in the Huanghuaihai region.Air temperatures in the plastic covered shed were 27-46℃ higher than the outside temperature (5 -13℃);there lative humidity under plastic was 16%-52% lower than that outside indicating that plastic covered sheds could increase alfalfa drying rate,helping to maintain forage value while eliminating the risk of high night humidity and rain.The moisture content of alfalfa dried under plastic was reduced to 15% after 32 hours,48 hours less than the control.The crude protein and total digestible nutri-ent contents were 18.64% and 66.72%,20.73% and 11.00% higher than the control,respectively;neutral detergent fiber and acid detergent fiber contents were 41.89% and 29.65%,12.60% and 17.87% lower than the control,respectively.Alfalfa dried under plastic dried more quickly and was of higher quality suggesting that the use of plastic covered drying sheds would be advantageous for farmers with relatively small areas of al-falfa who live in high rainfall areas.