YIELD OF BROMEGRASS AND REMOVAL OF NITROGEN, PHOSPHORUS AND POTASSIUM UNDER MODIFIED SOIL-TEMPERATURE FIELD CONDITIONS

[摘要] Ina3-yearfieldexperimentwithbromegrassgrownunderlowmoisturestress(lt; 2 atm),totalherbageyieldfromunfertilizedplotswasreducedby39%whentheaverageseasonalsoiltemperature(14.1 Cata50-cmdepth)wasloweredandmaintainedat9.2 C;theyieldwasincreasedby71%whentheseasonaltemperaturewasraisedandmaintainedat25.4 C.Thisrepresentsachangeinyieldof6.8%per1 Cchangeintheseasonalsoiltemperature,oraQ10of1.3at9.2 C.Herbagegrownonthewarmsoilscontinuedthroughouttheseasonuntilfall,butgrowthonthecoolsoilswasnegligibleafterthefirstharvestinJune.AdditionofN,PandKtothesoilinthespringreducedtheeffectofachangeinsoiltemperatureonherbageyield(3.7%per1 C).Theamountoftheyieldincrease,however,wassimilaratallthreesoiltemperatures.Incontrasttotheeffectonherbageyield,rootaccumulationwasmuchgreaterinthecoolsoil(30.7metrictonsperha,0to30 cmdepth)thanintheseasonalsoil(22.7 MT/...

[学科分类] 农业科学（综合）