Topographic controls on vegetation index in a hilly landscape: a case study in the Jiaodong Peninsula, eastern China

Abstract

This study examined topographic influence on spatial and temporal variability in the normalized difference vegetation index (NDVI) derived from the Satellite Pour l'Observation de la Terre-Vegetation at the regional and landscape scales in the Jiaodong Peninsula. The generalized additive models were used to quantify the spatial variation of NDVI attributable to local terrain and topographically related variables including altitude, exposure to incoming solar radiation, topographic wetness index, distance to the nearest stream and distance from the coast. NDVI distribution shows significant dependence on topography. The variables explained 38.3 % of variance in NDVI at the peninsula, and 30-45.3 % of variance in NDVI at the woodland, cropland, and grassland landscapes. At the Jiaodong Peninsula scale, NDVI is influenced primarily by distance from the coast. However, topographic wetness index has the most explanatory power for NDVI at the woodland, cropland, and grassland landscapes. Through a statistical nonparametric correlation analysis (Spearman's r), the study indicates that spatial distribution of NDVI changes during the period 1998-2009 and future change trend of persistence determined by Hurst exponent is closely associated with topography and topography-based attribution. These results highlight the importance of topographic changes at landscape and regional scales as an important control factor on NDVI patterns.

Topographic Effect on Spectral Vegetation Indices From Landsat Tm Data: Is Topographic Correction Necessary?

“…Based on this rationale, most studies consider that band ratio VIs (for example, the Normalized Difference Vegetation Index -NDVI) can overcome topographic effects on radiometric levels (Lee and Kaufman, 1986;Ekstrand, 1996;Huete at al., 1999). However, some studies showed that topography significantly affects VIs in rugged mountainous area (Verbyla et al, 2008;Veraverbeke et al, 2010;Wang et al, 2012). For example, Deng et al (2007) observed that the NDVI and the Normalized Difference Infrared Index (NDII) showed a significant correlation (r 2 ) (p = 0.001) with topography variables such as slope and the cosine of the aspect.…”

Multi-Scale Remote Sensing Assessment of Ecological Environment Quality and Its Driving Factors in Watersheds: A Case Study of Huashan Creek Watershed in China

“…Natural population growth and migration can result in urban expansion, reduced vegetative cover, and frequent changes in land use. Anthropogenic activity contributes to increased water use and elevated greenhouse gas emissions, affecting urban climate factors such as temperature, humidity, and aridity [69][70][71]. Elevation has a significant influence on factors such as rainfall distribution, temperature, radiation intensity, soil quality, plant ecology, growth, and overall ecological quality.…”

Wetland mapping and evaluating the impacts on hydrology, using geospatial techniques: a case of Geba Watershed, Southwest Ethiopia

“…A primary cause for this is rugged topography, except few areas in different parts of the watershed. Some studies showed that topography significantly affects VIs in a rugged mountainous area (Veraverbeke et al, 2010;Verbyla et al, 2008;Wang et al, 2012). Deng et al (2007) observed that the NDVI and the Normalized Difference Infrared Index (NDII) showed a significant correlation (r 2 ) (p = 0.001) with topography variables such as slope and the cosine of the aspect.…”