Trends and Variability of AVHRR-Derived NPP in India

Bala, G.; Joshi, Jaideep; Chaturvedi, Rajiv Kumar; Gangamani, Hosahalli V.; Hashimoto, Hirofumi; Nemani, R. R.

doi:10.3390/rs5020810

Cited by 69 publications

(52 citation statements)

References 37 publications

(66 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Empirically upscaled estimates of GPP in East Asia revealed a significant reduction in the summer of 2003 in response to meteorological anomalies [30]. Increased GPP has also been identified using diagnostic terrestrial biosphere models in China [31] and India [28].…”

Section: Introductionmentioning

confidence: 90%

“…In Southeast Asia, interannual variations in vegetation indices were found to be largely determined by the El Niño Southern Oscillation [27]. Furthermore, vegetation greenness was found to have increased in India because irrigated areas and fertilization use increased [28]. However, this increase in vegetation greenness has stagnated in recent years [29].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Recent Changes in Terrestrial Gross Primary Productivity in Asia from 1982 to 2011

et al. 2013

View full text Add to dashboard Cite

Past changes in gross primary productivity (GPP) were assessed using historical satellite observations based on the Normalized Difference Vegetation Index (NDVI) from the Advanced Very High Resolution Radiometer (AVHRR) onboard the National Oceanic and Atmospheric Administration (NOAA) satellite series and four terrestrial biosphere models to identify the trends and driving mechanisms related to GPP and NDVI in Asia. A satellite-based time-series data analysis showed that approximately 40% of the area has experienced a significant increase in the NDVI, while only a few areas have experienced a OPEN ACCESSRemote Sens. 2013, 5 6044 significant decreasing trend over the last 30 years. The increases in the NDVI are dominant in the sub-continental regions of Siberia, East Asia, and India. Simulations using the terrestrial biosphere models also showed significant increases in GPP, similar to the results for the NDVI, in boreal and temperate regions. A modeled sensitivity analysis showed that the increases in GPP are explained by increased temperature and precipitation in Siberia. Precipitation, solar radiation and CO 2 fertilization are important factors in the tropical regions. However, the relative contributions of each factor to GPP changes are different among the models.

show abstract

Section: Introductionmentioning

confidence: 90%

Section: Introductionmentioning

confidence: 99%

Recent Changes in Terrestrial Gross Primary Productivity in Asia from 1982 to 2011

et al. 2013

View full text Add to dashboard Cite

show abstract

“…However, there is significant variability among these models' results due to differences in formulation of ecosystem processes, underlying assumptions for their formulation in these models, and the uncertainties associated with observations used in understanding these processes [14,15]. For assessing NPP and its spatial and temporal trends, quite often a combination of models and observational proxies (e.g., NDVI) are used [16,17] to ensure the reliability of the results.…”

Section: Introductionmentioning

confidence: 99%

Global and Regional Variability and Change in Terrestrial Ecosystems Net Primary Production and NDVI: A Model-Data Comparison

et al. 2016

View full text Add to dashboard Cite

Abstract:The net primary productivity (NPP) is commonly used for understanding the dynamics of terrestrial ecosystems and their role in carbon cycle. We used a combination of the most recent NDVI and model-based NPP estimates (from five models of the TRENDY project) for the period 1982-2012, to study the role of terrestrial ecosystems in carbon cycle under the prevailing climate conditions. We found that 80% and 67% of the global land area showed positive NPP and NDVI values, respectively, for this period. The global NPP was estimated to be about 63 Pg C¨y´1, with an increase of 0.214 Pg C¨y´1¨y´1. Similarly, the global mean NDVI was estimated to be 0.33, with an increasing trend of 0.00041 y´1. The spatial patterns of NPP and NDVI demonstrated substantial variability, especially at the regional level, for most part of the globe. However, on temporal scale, both global NPP and NDVI showed a corresponding pattern of increase (decrease) for the duration of this study except for few years (e.g., 1990 and 1995-1998). Generally, the Northern Hemisphere showed stronger NDVI and NPP increasing trends over time compared to the Southern Hemisphere; however, NDVI showed larger trends in Temperate regions while NPP showed larger trends in Boreal regions. Among the five models, the maximum and minimum NPP were produced by JULES (72.4 Pg C¨y´1) and LPJ (53.72 Pg C¨y´1) models, respectively. At latitudinal level, the NDVI and NPP ranges were~0.035 y´1 to~´0.016 y´1 and~0.10 Pg C¨y´1¨y´1 to~´0.047 Pg C¨y´1¨y´1, respectively. Overall, the results of this study suggest that the modeled NPP generally correspond to the NDVI trends in the temporal dimension. The significant variability in spatial patterns of NPP and NDVI trends points to a need for research to understand the causes of these discrepancies between molded and observed ecosystem dynamics, and the carbon cycle.

show abstract

“…Similarly, de Jong et al (2011) found that many forested biomes experienced a decline in vegetation greenness. There is still no consistent result on trends of global vegetation activity (Bala et al, 2013).…”

Section: Introductionmentioning

confidence: 91%

Inter-annual and seasonal trends of vegetation condition in the Upper Blue Nile (Abay) Basin: dual-scale time series analysis

2015

View full text Add to dashboard Cite

Abstract.A long-term decline in ecosystem functioning and productivity, often called land degradation, is a serious environmental challenge to Ethiopia that needs to be understood so as to develop sustainable land use strategies. This study examines inter-annual and seasonal trends of vegetation cover in the Upper Blue Nile (UBN) or Abbay Basin. The Advanced Very High Resolution Radiometer (AVHRR)-based Global Inventory, Monitoring, and Modeling Studies (GIMMS) normalized difference vegetation index (NDVI) was used for long-term vegetation trend analysis at low spatial resolution. Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI data (MOD13Q1) were used for medium-scale vegetation trend analysis. Harmonic analyses and non-parametric trend tests were applied to both GIMMS NDVI and MODIS NDVI (2001-2011 data sets. Based on a robust trend estimator (Theil-Sen slope), most parts of the UBN ( ∼ 77 %) showed a positive trend in monthly GIMMS NDVI, with a mean rate of 0.0015 NDVI units (3.77 % yr −1 ), out of which 41.15 % of the basin depicted significant increases (p < 0.05), with a mean rate of 0.0023 NDVI units (5.59 % yr −1 ) during the period. However, the MODIS-based vegetation trend analysis revealed that about 36 % of the UBN showed a significant decreasing trend (p < 0.05) over the period 2001-2011 at an average rate of 0.0768 NDVI yr −1 . This indicates that the greening trend of the vegetation condition was followed by decreasing trend since the mid-2000s in the basin, which requires the attention of land users and decision makers. Seasonal trend analysis was found to be very useful to identify changes in vegetation condition that could be masked if only inter-annual vegetation trend analysis was performed. Over half (60 %) of the Abay Basin was found to exhibit significant trends in seasonality over the 25-year period (1982-2006). About 17 and 16 % of the significant trends consisted of areas experiencing a uniform increase in NDVI throughout the year and extended growing season, respectively. These areas were found primarily in shrubland and woodland regions. The study demonstrated that integrated analysis of inter-annual and intra-annual trends based on GIMMS and MODIS enables a more robust identification of changes in vegetation condition.

show abstract

Trends and Variability of AVHRR-Derived NPP in India

Cited by 69 publications

References 37 publications

Recent Changes in Terrestrial Gross Primary Productivity in Asia from 1982 to 2011

Recent Changes in Terrestrial Gross Primary Productivity in Asia from 1982 to 2011

Global and Regional Variability and Change in Terrestrial Ecosystems Net Primary Production and NDVI: A Model-Data Comparison

Inter-annual and seasonal trends of vegetation condition in the Upper Blue Nile (Abay) Basin: dual-scale time series analysis

Contact Info

Product

Resources

About