Analysis of the spectral response of Tamarix spp vegetation to the soil salinity based on ground spectral measurements

In this paper, the field-derived hyperspecral reflectance of the Tamarix spp vegetation and background soil parameters (soluble salt content and eight base ions) of associated saline soil at the lower reaches of the Tarim River were measured and studied. The spectral responses of the Tamarix spp canopy with different level saline soil, and the relationship between soil salt variables and vegetation spectral indices were analyzed in order to understand the sensitive bands and the appropriate vegetation spectral indices. The results revealed that:(1) the spectra at band ranges 600-750nm,1350-1550nm change regularly with the increasing salt content of the background soil. (2) The removal continuum reflectance shows that the three absorb troughs with band ranges 460-560nm, 560-760nm,1050-1300nm, 1300-1700nm, can play an important role in indicating increasing changes of soil salt. Theses sensitive bands just reflect the characteristics of the chlorophyll content, moisture content of the vegetation. It presents a negative correction between the absorption valley changing trend and the salt content in the background soil. When the soil salinity content is higher, the corresponding absorption valley value that reflects vegetation growth condition characteristic is not more obvious. (3) Further analysis are conducted on the absorption width at the band range 1300-1700nm, the absorption width at the band range 560-760nm, λred, absorption depth at the band range 1050-1300nm, R1450, MSAVI, trough area of the band range 560-760nm, λred and the absorption depth at the band range 560-760nm, these nine indices can be used to predict salt values of saline soil and evaluate the degree of soil salinity.

[1]  B. Henderson,et al.  Vegetation indicators of salinity in northern Queensland , 2003 .

[2]  E. Davidson,et al.  Satellite-based modeling of gross primary production in an evergreen needleleaf forest , 2004 .

[3]  G. Taylor,et al.  Field-derived spectra of salinized soils and vegetation as indicators of irrigation-induced soil salinization , 2002 .

[4]  Raymond F. Kokaly,et al.  Investigating a Physical Basis for Spectroscopic Estimates of Leaf Nitrogen Concentration , 2001 .

[5]  Massimo Menenti,et al.  A field experiment on spectrometry of crop response to soil salinity , 2007 .

[6]  S. K. McFeeters.  The use of the Normalized Difference Water Index (NDWI) in the delineation of open water features , 1996 .

[7]  D. Horler,et al.  The red edge of plant leaf reflectance , 1983 .

[8]  Conceição Santos.  Regulation of chlorophyll biosynthesis and degradation by salt stress in sunflower leaves , 2004 .

[9]  A. Huete.  A soil-adjusted vegetation index (SAVI) , 1988 .

[10]  Jiyuan Liu,et al.  Characterization of forest types in Northeastern China, using multi-temporal SPOT-4 VEGETATION sensor data , 2002 .

[11]  A. Huete,et al.  A Modified Soil Adjusted Vegetation Index , 1994 .

[12]  J. H. Everitt,et al.  Comparison of multispectral video and SPOT-1 HRV observations for cotton affected by soil salinity , 1992 .

[13]  Didier Tanré,et al.  Atmospherically resistant vegetation index (ARVI) for EOS-MODIS , 1992, IEEE Trans. Geosci. Remote. Sens..

[14]  Moon S. Kim,et al.  The use of high spectral resolution bands for estimating absorbed photosynthetically active radiation (A par) , 1994 .

[15]  Josep Peñuelas,et al.  Visible and Near‐Infrared Reflectance Assessment of Salinity Effects on Barley , 1997 .

[16]  K. D. Sharma,et al.  Effect of chloride and sulphate types of salinity on characteristics of chlorophyll content, photosynthesis and respiration of chickpea (Cicer arietinum L.) , 1990, Biologia plantarum.

[17]  Liu Wei-dong.  Relationships between Rice LAI, CH.D and Hyperspectra Data , 2000 .