中文摘要：

【目的】分析不同收割高度玉米秸秆的产量、含水量、营养物质含量和产量，以期为该地区玉米秸秆作为反刍动物饲料提供最佳收获高度做参考依据。【方法】在小麦一玉米一年两熟制的黄淮海地区进行田间试验，玉米成熟收获后，根据机收距离地面的可能高度，将玉米秸秆分为距地面0-50cm、0--100cm、0cm以上、50cm以上和100cm以上5个处理，分别测定各处理秸秆的干重（DW）、鲜重（FW）和含水量（WC），秸秆的粗蛋白（CP）、粗脂肪（EE）、中性洗涤纤维（NDF）、酸性洗涤纤维（ANF）、淀粉（sc）、可溶性糖（SS）、钙（Ca）、磷（P）和钾（K）的含量及产量。【结果】玉米秸秆的CP、BE、Ca和P含量随距地高度升高而增加，玉米秸秆的WC、NDF、ADF、SS、SC和K含量随距地高度升高而降低。100cm以上处理的Dw、CP、NDF、ANF、SS、SC和K的产量均占总产量的30％左右，而EE、Ca和P的产量均占总产量的40％左右。50cm以上处理的Fw和K产量占总产量的5O％左右，而Dw和除K外各营养物质的产量均占总产量的60％-70％。【结论】从秸秆营养物质的含量和产量上分析，100cm以上部位比50cin以上部位更适合作饲料。因此，该地区机收玉米秸秆用作饲料最适宜的高度是距地面100cm。

英文摘要：

[ Objective ] This study analyzed the nutrients composition, water content and yield of different cutting heights of maize stover in attempt to provide a reference for selection of the best cutting height to feed the ruminants. [Method] A field experiment was carded out in the Huang-Huai-Hai region of a typical wheat-maize cropping system. After maize was harvested, its stover was cut at different heights, including above 100 cm, above 50 era, above 0 cm, below 100 cm and below 50 cm from the ground. Some physiological indexes of different heights of maize stover were analyzed, respectively, which included moisture content （MC）, dry weight （DW）, fresh weight （FW）, content and yield of crude protein （CP）, crude fat （EE）, neutral and acid detergent fiber （NDF and ADF）, starch （SC）, soluble sugar （SS）, calcium （Ca）, phosphorus （P） and potassium （K） of different treatments, respectively. [Result] With the increase of harvesting height, the content ofCP, EE, Ca and P gradually increased, but the contents of MC, SS, NDF, ADF, SC and K gradually reduced, respectively. The production of DW, CP, NDF, ADF, SC and K accounted for about 30% of the total production, respectively; however, the production of Ca, EE and P accounted for about 40% of total production in the above 100 cm treatment, respectively. The production of FW and K accounted for about 50 percent of the total production, the production of DW and nutrients composition except K accounted for 60% to 70% in the above 50 cm treatment. [Conclusion] From the content and yields of the nutrients, the above 100 cm treatment is best for forage. Therefore, it is recommended that 100 cm from the ground is a suitable height used for forage when maize is harvested in the mechanical harvesting system.