资源简介

摘要： 叶面积指数(LeafAreaIndex,LAI)是表征植被生物物理变化和冠层结构特征的关键参数,目前存在多个全球范围、长时间序列LAI产品,对其进行验证是LAI产品应用的重要前提,然而目前山区的验证工作尤其少见.在我国西南山区选取６个典型样区,考虑山区复杂地形特征,从产品时空完整性以及对山区植被时空特征表征能力等方面对GEOV１、GLASS和MODISLAI产品进行对比分析.研究结果表明:①相比于地形平坦地区,在山区随海拔和地形起伏度的增加,LAI产品时空完整性呈递减的趋势,其中,GEOV１LAI表现最差,MODISLAI次之,GLASSLAI表现最好;②GLASSLAI和GEOV１LAI的空间分布合理且具有较好的一致性,MODISLAI的空间分布和二者存在差异,３种LAI产品均难以准确反映山区植被垂直带谱的变化特征;③草地类型LAI产品间差值较小,林地和农作物GLASSLAI和GEOV１LAI产品一致性较好,MODISLAI产品和二者存在较大的差异;④GLASSLAI时间序列曲线平滑且连续,GEOV１LAI存在时间不连续现象,MODISLAI季相变化中的波动现象比较严重;各产品不仅难以准确反映冬季的常绿针叶林LAI,而且难以准确表征样区内农田作物轮作的物候信息.对比分析有助于发现LAI产品在山区存在的问题,并为今后LAI产品的算法改进提供帮助和参考. 关键词： 叶面积指数产品;  山区;  时空特征;  交叉验证     Abstract: Leaf Area Index(LAI) is a key biophysical variable for describing the canopy architecture.Currently,several global scale and long term LAI data sets have been produced.Validation of the LAI products is critical for their proper use in land surface models.However,existing studies were limited over flat terrain,the performance of the LAI data sets in mountainous area is still unknown.To fill this gap,the GEOV1,GLASS and MODIS LAI products were indirectly validated over mountainous area,southwestern China.The validation was conducted through the evaluation of the spatio\|temporal continuity and the capability to capture phonological characteristics.The results indicate that LAI products shows worse spatio\|temporal continuity in mountainous area than that in flat area.The best continuity is achieved by GLASS in our study areas and the worst is from GEOV1.GEOV1 and GLASS LAI product shows good spatial consistency,but MODIS is different from them.All products can hardly capture the details of the altitudinal distribution of biome types.The difference between the three products can be neglected over grassland but obvious over forests and cropland.GLASS LAI time series are smooth and continuous.GEOV1 LAI time series have lots of gaps and MODIS LAI time series are very shaky.All three LAI products display unreasonable seasonality for evergreen needleleaf forests and crops.This study may facilitate  the improvement of the quality of LAI product over mountainous areas.

相关资源

1. 水质遥感监测的关键要素叶绿素a的反演算法研究进展
2. 基于无人机遥感技术的森林参数获取研究进展
3. 基于无线传感器网络的森林生态系统观测试验平台构建
4. 基于无人机激光雷达的森林冠层高度分析
5. 多源时序国产卫星影像的森林火灾动态监测
6. 基于无人机遥感技术的台风灾害倒伏绿化树木检测

下载说明

·如果您发现该资源不能下载，请通知管理员.gissky@gmail.com

·为确保下载的资源能正常使用，请使用[WinRAR v3.8]或以上版本解压本站资源,缺省解压密码www.gissky.net ，如果是压缩文件为分卷多文件，请依次下载每一个文件，并按照顺序命名为1.rar,2.rar,3.rar...，然后鼠标右击1.rar解压.

·为了保证您快速的下载速度，我们推荐您使用[网际快车]等专业工具下载.

·站内提供的资源纯属学习交流之用,如侵犯您的版权请与我们联系.