The increasing number of sensor types for terrestrial remote sensing has necessitated supplementary efforts to evaluate and standardize data from the different available sensors. In this study, we assess the potential use of IKONOS, ETM+, and SPOT HRVIR sensors for leaf area index (LAI) estimation in forest stands. In situ measurements of LAI in 28 coniferous and deciduous stands are compared t...

Several soiland atmospheric correcting variants of the normalized difference vegetation index (NDVI) have been proposed to improve its accuracy in estimating biophysical plant parameters. In this study, a sensitivity analyses, utilizing simulated and observational data, was conducted on the NDVI and improved variants by analyzing the atmospheric-and soilperturbed responses of each VI as a conti...

the normalized difference vegetation index (ndvi) derived from the spot 4 satellite has been widely used to monitor moisture-related vegetation condition. the relationship between vegetation and climate index, however, is complex and has not been adequately studied with satellite sensor data. to better understand this relationship, an analysis was conducted on time series of monthly ndvi (1999–...

Urbanization, a dominant global demographic trend, leads to various changes in environments (e.g., atmospheric CO2 increase, urban heat island). Cities experience global change decades ahead of other systems so that they are natural laboratories for studying responses of other nonurban biological ecosystems to future global change. However, the impacts of urbanization on vegetation growth are n...

This study presented a MODIS 8-day 1 km evapotranspiration (ET) downscaling method based on Landsat 8 data (30 m) and machine learning approaches. Eleven indicators including albedo, land surface temperature (LST), and vegetation indices (VIs) derived from Landsat 8 data were first upscaled to 1 km resolution. Machine learning algorithms including Support Vector Regression (SVR), Cubist, and Ra...

to evaluate the capability of irs-p6 liss-iii data to be employed for monitoring the pollarding forest areas in northern zagros, some parts of pollarded forests located around baneh city were selected as a case study area. the pollarding area was determined as the ground truth in a 3-year alternation period using a global positioning system (gps). radiometric and geometric corrections were appl...

In monitoring vegetation change and urban planning, the measure and the mapping of the green vegetation over the Earth play an important role. The normalized difference vegetation index (NDVI) is the most popular approach to generate vegetation maps for remote sensing imagery. Unfortunately, the NDVI generates low-resolution vegetation maps. Highresolution imagery, such as IKONOS imagery, can b...

Located in the central Chinese Loess Plateau, the Jinghe River is one of the major tributaries of the Yellow River, and the river basin it inhabits is characterized by a continental climate. Considering that land degradation has been the main ecological problem in the Jinghe River Basin, there is an urgent need to scientifically explore the land degradation mechanism in order to restore natural...

Severe droughts strongly impact photosynthesis (GPP), and satellite imagery has yet to demonstrate its ability to detect drought effects. Especially changes in vegetation functioning when vegetation state remains unaltered (no browning or defoliation) pose a challenge to satellite-derived indicators. We evaluated the performance of different satellite indicators to detect strong drought effects...