Effects of precipitation, temperature and topographic parameters on evergreen vegetation greenery in the Western Ghats, India

Abstract

Bi-weekly National Oceanic and Atmospheric Administration-advanced very high-resolution radiometer (NOAA-AVHRR) satellite data covering a fourteen-year time period (1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003) were used to examine spatial patterns in the normalized difference vegetation index (NDVI) and their relationships with environmental variables covering tropical evergreen forests of the Western Ghats, India. NDVI values and corresponding environmental variables were extracted from 23 different forested sites using the NOAA-AVHRR global inventory monitoring and modelling studies (GIMMS) dataset. We specifically used the partial least square (PLS) multivariate regression technique that combines features from principal component analysis and multiple regression to link spatial patterns in NDVI with the environmental variables. PLS regression analysis suggested the two-component model to be the best model, explaining nearly 71% of the variance in the NDVI datasets with relatively good R 2 value of 0.78 and a predicted R 2 value of 0.74. The most important positive predictors for NDVI included Riva's continentality index, precipitation indicators summed over different quarters, average precipitation and elevation. Also, the results from PLS regression clearly suggested that bio-climatic indicators that relied only on precipitation parameters had much more positive influence than indicators that combined both temperature and precipitation together. These results highlight the climatic controls of vegetation vigor in evergreen forests and have implications for monitoring bio-spheric activity, developing prognostic phenology models and deriving land cover maps in the Western Ghats region of India.

Variations of NDVI and Its Association with Rainfall and Evapotranspiration over Bangladesh

“…[9] reports that the vegetation over India is decreasing during drought years while opposite results are shown during flood years. There are many studies done over Indian subcontinent on vegetation variability and its relation to meteorological parameters [5,12]. In order to understand the association of NDVI with rain fall over Bangladesh interannual variations, spatial correlation, scatter plot and annual correlation analysis are observed.…”

Assessing the Climatic Effects on Vegetation Dynamics in the Mekong River Basin

“…Average, minimum, and maximum temperatures were important driving factors in the evergreen forest dynamic, having positive effects. Similarly, Prasad et al [2] concluded that the Continental Index-the difference between minimum and maximum temperature-demonstrated a higher influence on the evergreen forest compared with the combined precipitation parameters and topographic parameters. Moreover, Guo et al [19] suggested that the rising temperature may increase forest growth at the beginning of the growing period, but precipitation may decrease NDVI in the forest biome.…”

“…were used to identify the driving climatic factors and their effects on vegetation dynamics [2,3]. The conclusions are illustrated in Table 3.…”

“…Climate change is increasing the frequency of such disturbances [1], which alters vegetation dynamics. Many earlier studies focused on ecological responses to climate change, and found that climate contributions to vegetation change are most crucial in many regions [2][3][4][5][6][7][8]. Hence, assessing the ecological effects of climate change on vegetation biomass is of importance for understanding and estimating climate-induced vegetation change in the last few decades, and disentangle it from the effect of other kind of disturbances.…”

Variability in MODIS NDVI in Relation to Southwest Monsoon over Western Ghats, India

“…It is also reported that due to climate change, the Western Ghats is going to receive exceptional amounts of rainfall during south west monsoon season which brings high contrast in the plant richness and diversity. Prasad et al (2008) studied the effects of precipitation, temperature and topographic parameters on evergreen vegetation greenery in the Western Ghats, India and reported that the vegetion in Western Ghats is strongly dependant on seasonal rainfall. However, a few reports only available on the relationship of NDVI and rainfall and other climatic indices.…”