大穗型小麦产量形成过程中光合特性的动态变化

在大田条件下，对8个大穗型小麦新品系和多穗型品种西农979(对照)的产量性状以及不同生育期叶片光合速率、叶绿素荧光参数、叶绿素含量(Chl)和叶面积指数(LAI)进行研究.结果表明：除单位面积穗数低于对照外，8个新品系的穗粒数、穗粒重和千粒重均显著高于对照，大穗型小麦新品系2036、2037、2038、2039和2040的产量显著高于对照；8个新品系的平均光合速率(P_n)与对照差异不显著，而PSⅡ最大光能转换效率、PSⅡ实际量子效率、光化学猝灭系数和PSⅡ反应中心活性均高于对照；品系2037、2040、2039、2038和2036的Chl比对照分别提高17.5%、19.1%、15.3%、13.9%和7.9%；大穗型小麦品系的LAI明显高于对照，且在生育后期下降缓慢.

Landscape ecological health assessment of tourist islands: A case of Meizhou Island, the Mazu Holy Land of Fujian Province, East China

By defining the concept of landscape ecological health of tourist islands(LEHTI),a LEHTI evaluation system was established with the model of pressure-state-response,and an ideal health state value was determined.In addition,by adopting the methods of entropy weight and gray correlation fuzzy,the evaluation results were calculated and classified into five grades,according to their distances to the ideal value.Based on these results,the specific damage of tourist island landscape ecosystem as well as the main stress factors and the evolution trend behind the damage were identified,which could provide scientific basis for the subsequent ecological restoration and optimizing measures.Taking the representative tourist island of Mazu Holy Land as a case,and with the support of RS and GIS techniques,the satellite remote sensing and socioeconomic survey data of 1993,1999,2005,and 2009 were integrated and demonstrated.The process and results of this case study showed that the LEHTI evaluation system and its methods were feasible,and could provide solid basis for resource and environment management.