The leaf area index (LAI) is a very important parameter affecting land-atmosphere exchanges in land梥urface processes; LAI is one of the basic feature parameters of canopy structure, and one of the most important biophysical parameters for modeling ecosystem processes such as carbon and water fluxes. Remote sensing provides the only feasible option for mapping LAI continuously over landscapes, but existing methodologies have significant limitations. To detect LAI accurately and quickly is one of tasks in the ecological and agricultural crop yield estimation study, etc. Emerging hyperspectral remote sensing sensor and techniques can complement existing ground-based measurement of LAI. Spatially explicit measurements of LAI extracted from hyperspectral remotely sensed data are component necessary for simulation of ecological variables and processes. This paper firstly summarized LAI retrieval method based on different level hyperspectral remote sensing platform (i. e. , airborne, satellite-borne and ground-based); and secondly different kinds of retrieval model were summed up both at home and abroad in recent years by using hyperspectral remote sensing data; and finally the direction of future development of LAI remote sensing inversion was analyzed.%以氧化镧、氧化镝、偏钒酸铵和硝酸等为原料,采用乙醇-水混合溶剂热法并通过调节体系pH成功合成了LaVO4∶Dy3+纳米棒,运用X射线衍射、透射电镜、红外光谱、紫外-可见漫反射光谱和荧光光谱等对样品进行了表征.结果表明,pH从2升到4,样品由单斜晶系转化为四方锆石型结构,并且随着pH的增大,晶体的晶粒尺寸变小,样品由不规则颗粒逐步向一维棒状样品转变,其能带隙从3.68(pH 2)减小到3.43 eV(pH 10).荧光结果表明,相比不规则形貌纳米颗粒,LaVO4∶Dy3+纳米棒的最大激发峰发生一定程度的红移,具有最强的黄光发射(4F9/2-6H13/2)和蓝光发射(4F9/2-6H15/2),而且其黄蓝光强度比值(Y/B)达到最大值(1.039).
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