刈割对草甸草原羊草、无芒雀麦再生和碳水化合物含量的影响  

Effect of clipping on the regrowth and carbohydrate content of Leymus chinensis and Bromus inermis in meadow steppes

作　　者：肖红 杨合龙[1] 戎郁萍[1] 杨晗[1] XIAO Hong;YANG Helong;RONG Yuping;YANG Han(College of Animal Science and Technology,China Agricultural University,Beijing 100193,China)

机构地区：[1]中国农业大学动物科技学院,北京100193

出　　处：《草业科学》2018年第9期2201-2209,共9页Pratacultural Science

基　　金：国家重点研发计划"典型脆弱生态修复与保护研究"(2016YFC0500603)

摘　　要：牧草的再生性能是草地持续利用的基础,牧草贮藏的碳水化合物对牧草再生具有重要作用。本研究针对刈割强度对羊草(Leymus chinensis)和无芒雀麦(Bromus inermis)现存量、再生速度及不同部位碳水化合物的影响进行了分析研究,结果表明,羊草和无芒雀麦地上部现存量随留茬高度的降低呈降低趋势;第2次刈割后,羊草和无芒雀麦留茬4cm的再生速度均高于留茬8和12cm。刈割后无芒雀麦不同部位可溶性糖含量均在第2次刈割后16d上升,到秋季枯黄期降至最低值,且未恢复到刈割前水平。第2次刈割后16d,羊草茎基部还原糖含量可恢复到刈割前水平,而无芒雀麦茎基部还原糖含量降至刈割后最低值,到秋季枯黄期,留茬12cm羊草和无芒雀麦茎基部还原糖含量可达到刈割前水平。试验期间牧草主要生长季(6-8月)降水较少,严重抑制了羊草和无芒雀麦的再生和碳水化合物的贮藏。因此生长季降水少的干旱年份,羊草和无芒雀麦草地以留茬8~12cm、刈割1次为宜。The regrowth capability of herbage is the basis of sustainable utilization of grassland;carbohydrate reserves play an important role in this regrowth.The effects of clipping intensity on the aboveground standing crop,its regrowth speed,and carbohydrate content in its different organs were evaluated in Leymus chinensis and Bromus inermis.The results showed that the aboveground standing crop of L.chinensis and B.inermis reduced with a decrease in the stubble height.The regrowth speed of 4 cm stubbles was faster than that of 8 and 12 cm stubbles after the second clipping.The soluble sugar content in different parts of B.inermis increased 16 days after the second clipping and decreased to the lowest value during the withering period;this amount was not restored to the amount present before clipping.The reducing sugar content in the stem base of L.chinensis was restored to the level present before the clipping 16 days after the second clipping,whereas the reducing sugar content in the stem base of B.inermis decreased to the lowest value after clipping during the withering period.The reducing sugar content in the stem base of L.chinensis and B.inermis at the 12 cm stubble height reached the levels before clipping.The main growing season(June-August)of the herbage had less precipitation during the experimental period,which severely inhibited the regrowth and carbohydrate reserves in L.chinensis and B.inermis.Therefore,it is optimal to clip the herbage once and increase the stubble height to 8~12 cm in L.chinensis and B.inermis grasslands during the growing seasons in years with less precipitation.

关 键 词：留茬高度 草甸草原 茎基 根系 再生速度 可溶性糖 还原糖 

分 类 号：S812[农业科学—草业科学] S543.9[农业科学—畜牧学]