Leaf biochemical properties have been widely assessed using hyperspectral reflectance information by inversion of PROSPECT model or by using hyperspectral indices, but few studies have focused on arid ecosystems. As a...Leaf biochemical properties have been widely assessed using hyperspectral reflectance information by inversion of PROSPECT model or by using hyperspectral indices, but few studies have focused on arid ecosystems. As a dominant species of riparian ecosystems in arid lands, Populus euphratica Oliv. is an unusual tree species with polymorphic leaves along the vertical profile of canopy corresponding to different growth stages. In this study, we evaluated both the inversed PROSPECT model and hyperspectral indices for estimating biochemical properties of P. euphratica leaves. Both the shapes and biochemical properties of P. euphratica leaves were found to change with the heights from ground surface. The results indicated that the model inversion calibrated for each leaf shape performed much better than the model calibrated for all leaf shapes, and also better than hyperspectral indices. Similar results were obtained for estimations of equivalent water thickness （EWT） and leaf mass per area （LMA）. Hyperspectral indices identified in this study for estimating these leaf properties had root mean square error （RMSE） and R2 values between those obtained with the two calibration strategies using the inversed PROSPECT model. Hence, the inversed PROSPECT model can be applied to estimate leaf biochemical properties in arid ecosystems, but the calibration to the model requires special attention.展开更多
Leaf variegation,the mosaic of colors on the leaf surface,can be developed by certain plant species without external influence.Although it may be associated with a variety of functions,the stable existence of differen...Leaf variegation,the mosaic of colors on the leaf surface,can be developed by certain plant species without external influence.Although it may be associated with a variety of functions,the stable existence of different leaf color morphs within a plant species has not been fully explained by previous studies.This study focuses on the two leaf morphs of Cypripedium forrestii,an endangered lady slipper orchid,and compares their micromorphological structure,photosynthetic potential,differentially expressed genes(DEGs),and ecological features to gain a comprehensive understanding of the underlying leaf variegation polymorphism.Our findings demonstrate that leaf variegation is not pathological and does not affect photosynthetic potential.Additionally,it significantly reduces herbivory damage.We found that the probability of herbivory and leaf area loss for variegated leaves was notably higher under drought conditions.Therefore,variegated individuals may be more adaptive under such conditions,while non-variegated ones may be more cost-effective in normal years.These results suggest that different leaf color morphs may be favored by varying environmental conditions,and leaf polymorphism may be a legacy of ancient climate and herbivore fluctuations.展开更多
基金supported by the West Light Talents Cultivation Program of Chinese Academy of Sciences (XBBS 200801)the National Natural Science Foundation of China (40801146)the JSPS Project (21403001)
文摘Leaf biochemical properties have been widely assessed using hyperspectral reflectance information by inversion of PROSPECT model or by using hyperspectral indices, but few studies have focused on arid ecosystems. As a dominant species of riparian ecosystems in arid lands, Populus euphratica Oliv. is an unusual tree species with polymorphic leaves along the vertical profile of canopy corresponding to different growth stages. In this study, we evaluated both the inversed PROSPECT model and hyperspectral indices for estimating biochemical properties of P. euphratica leaves. Both the shapes and biochemical properties of P. euphratica leaves were found to change with the heights from ground surface. The results indicated that the model inversion calibrated for each leaf shape performed much better than the model calibrated for all leaf shapes, and also better than hyperspectral indices. Similar results were obtained for estimations of equivalent water thickness （EWT） and leaf mass per area （LMA）. Hyperspectral indices identified in this study for estimating these leaf properties had root mean square error （RMSE） and R2 values between those obtained with the two calibration strategies using the inversed PROSPECT model. Hence, the inversed PROSPECT model can be applied to estimate leaf biochemical properties in arid ecosystems, but the calibration to the model requires special attention.
基金supported by:Science&Technology Basic Resources Investigation Program of China for Survey and Germplasm Conservation of PSESP in Southwest China(2017FY100100)the Second Tibetan Plateau Scientific Expedition and Research Program(2019QZKK0502)+1 种基金the PSESP project of Yunnan Forestry and Grassland Bureau(2021SJ14X-09)and the project“Collection and Conservation of Plant Species with Extremely Small Populations of Polystichum glaciale and Cypripedium forrestii in Lijiang”(2021SJ14X-11).
文摘Leaf variegation,the mosaic of colors on the leaf surface,can be developed by certain plant species without external influence.Although it may be associated with a variety of functions,the stable existence of different leaf color morphs within a plant species has not been fully explained by previous studies.This study focuses on the two leaf morphs of Cypripedium forrestii,an endangered lady slipper orchid,and compares their micromorphological structure,photosynthetic potential,differentially expressed genes(DEGs),and ecological features to gain a comprehensive understanding of the underlying leaf variegation polymorphism.Our findings demonstrate that leaf variegation is not pathological and does not affect photosynthetic potential.Additionally,it significantly reduces herbivory damage.We found that the probability of herbivory and leaf area loss for variegated leaves was notably higher under drought conditions.Therefore,variegated individuals may be more adaptive under such conditions,while non-variegated ones may be more cost-effective in normal years.These results suggest that different leaf color morphs may be favored by varying environmental conditions,and leaf polymorphism may be a legacy of ancient climate and herbivore fluctuations.
