水分胁迫对混播草坪生理生态特性的影响

为了研究混播草坪抗水分胁迫能力，采用盆栽试验与大田试验相结合的方法，以草地早熟禾（Poa pretensis）单播草坪（简称T1）为对照，以草地早熟禾、高羊茅（Festuca arundinacea）、多年生黑麦草（Loli-um perenne）混播草坪（简称T2，混播比例为6∶2∶2）和草地早熟禾、紫羊茅（F．rubra）、细弱翦股颖（Agrostis tenuis）混播草坪（简称T3，混播比例为5∶4∶1）为研究对象，分析水分胁迫对混播草坪生理生态特性的影响。结果表明，随着水分胁迫增加，3种草坪的外观质量综合评价表现为T1＞T2＞T3；单播草坪土壤含水量、叶片相对含水量及根系活力下降幅度均低于混播草坪，变幅表现为T3＞T2＞T1；而叶片叶绿素含量均值表现为T1＞T2＞T3。3种供试草坪抗水分胁迫能力表现为T1＞T2＞T3，T1适宜的土壤含水量占田间持水量百分比范围为84．5％～94．8％，T2为80．4％～91．8％，T3为77．5％～90．7％。

Influence of Water Stress on Physical Ecology Characteristics\= of Mixed Lawn Grass

The resistance to water stress of three kinds of lawns were studied by pot experiment and field experiment.The T1 lawn as control contained single species Poa pretensis,the T2 lawn consisted of P.pretensis, Festuca arundinacea and Lolium perenne with the mixed ratio of 6∶2∶2,and the T3 lawn consisted of P.pretensis, F.rubra and Agrostis tenuis with the mixed ratio of 5∶4∶1 .The results were as following：along with the enhance-ment of water stress,the appearance quality comprehensive evaluation was in the order of T1 〉T2 〉T3 .T1 had the lowest decline of soil water content,leaf relative water content and root activity,followed by T2 ,and then T3 .The chlorophyll content in leaves followed the order of T1 〉T2 〉T3 .The resistance of these lawns to water stress were T1 〉T2 〉T3 .These lawns had different optimum soil water content,which the percentage of soil water content to field water capacity was 84.5%-94.8% for T1 ,80.4%-91 .8% for T2,and 77.5%-90.7% for T3.