留茬高度对青海草地早熟禾人工草地禾草生物量和品质的影响

Effects of stubble height on grass biomass and quality in Poa Pratensis L.cv.Qinghai artificial grassland

研究留茬高度对青海草地早熟禾人工草地禾草生物量和品质的影响有助于高寒地区人工草地的可持续利用和放牧管理。该试验以青海草地早熟禾人工草地禾草为研究对象,通过设置不同留茬高度(轻度:留茬10 cm,中度:留茬5 cm,重度:留茬2 cm),研究刈割对草产量和牧草品质的影响。结果表明,随着刈割留茬高度的降低,禾草株高、再生高、地上生物量呈显著降低趋势(P<0.05),但对照组和轻度刈割组间差异不显著(P>0.05);粗蛋白质、粗灰分、Ca、P等营养成分、相对饲喂价值显著增加(P<0.05),粗纤维、酸性洗涤纤维、中性洗涤纤维等营养成分显著降低(P<0.05);粗蛋白质、粗纤维、粗灰分、粗脂肪、酸性洗涤纤维、中性洗涤纤维营养成分产量逐渐降低。地上生物量与营养品质等指标间的相关关系显著(P<0.05)。可见,在青海省祁连山区种植的青海草地早熟禾适宜轻度刈割或轻度放牧,中度和重度刈割不利于植株生长和营养物质积累。

Studying the effects of stubble height on grass biomass and quality of Precocious grass fields is helpful for sustainable utilization and grazing management of artificial grassland in alpine region.The experiment was conducted to study the effects of mowing on the yield and forage quality of Poa Pratensis L.cv.Qinghai in artificial grassland by setting different mowing intensities(mild:stubble 10 cm,moderate:stubble 5 cm,severe:stubble 2 cm),mainly by field observation and laboratory analysis.The results showed that the Plant height,regeneration height and aboveground biomass of Poa Pratensis L.cv.Qinghai had significant downward trend of stubble height(P<0.05),but there were no significant differences between control and light mowing treatments(P>0.05).Crude Protein,crude ash,Ca,P and relative feeding value were increased(P<0.05),while crude fiber,acid detergent fiber and neutral detergent fiber were basically significantly decreased(P<0.05).The yield of nutrient composition yield of crude protein,crude fiber,crude ash,crude fat,acid detergent fiber and neutral detergent fiber decreased gradually.The correlations between aboveground biomass and nutrient quality were significant(P<0.05).In conclusion,moderate and heavy mowing of Poa Pratensis L.cv.Qinghai in Qilian mountain area of Qinghai province was not conducive to the growth and nutrient accumulation of herbage plants,and light mowing or similar light grazing was suitable.