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Application of the Standardized Precipitation index and normalized difference vegetation index for Evaluation of Irrigation Demands at Three Sites in Jamaica

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JOURNAL OF IRRIGATION AND DRAINAGE ENGINEERING 2013年第11期139卷 922-932页

作者： Richards, Johanna Madramootoo, Chandra A. Goyal, Manish Kumar Trotman, Adrian McGill Univ Dept Bioresource Engn Ste Anne De Bellevue PQ H9X 3V9 Canada Caribbean Inst Meteorol & Hydrol BB-23006 Husbands St James Barbados

Agricultural production is a significant contributor to the economy of Jamaica, which is situated in the northwestern Caribbean Sea;this production is heavily dependent on seasonal rainfall because only approximately 10% of Jamaica's cultivated lands are irrigated. Drought is a disastrous natural phenomenon that has a significant impact on socioeconomics, agriculture, and the environment. In the 2000-2001 drought experienced in Jamaica, there were crop losses amounting up to US$6million. Hence, drought index information is essential for better planning for drought impacts and allows for the introduction of mitigation measures in the agricultural sector. Therefore, the objective of this paper is to evaluate the suitability of both the Standardized Precipitation index (SPI) and the normalized difference vegetation index (NDVI) in reflecting water stressed conditions and irrigation demand requirements for three agricultural sites: Savanna-la-Mar in the parish of Westmoreland, Beckford Kraal in the parish of Clarendon, and Serge Island in the parish of St. Thomas, all in Jamaica. These sites were selected based on soil characteristics, historical rainfall data, and farming practices. The results indicate that the NDVI provides a suitable representation of these areas for only the driest months of the year, and that either the one-month or three-month SPI was found to be more representative of soil moisture conditions. Furthermore, a correlation analysis was also conducted between the SPI and soil moisture for El Nino years only, because the El Nino/Southern Oscillation phenomenon has been responsible for many of the droughts Jamaica has experienced. In these years, good correlations between soil moisture and the one-month and three-month SPI were obtained in some wet months, in addition to the dry months. This paper provides soil moisture values for all of the different categories and values of the SPI relating to water scarcity. It also provides irrigation requirements

关键词： Correlation Precipitation vegetation Irrigation Caribbean Standardized Precipitation index normalized difference vegetation index Correlation analysis Regression Irrigation management

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Cross-calibration of Indian Mini Satellite-1 HySI data using Hyperion: effect on normalized difference vegetation index

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CURRENT SCIENCE 2012年第5期103卷 480-481页

作者： Mehta, Manu Agrawal, Shefali Indian Inst Remote Sensing Photogrammetry & Remote Sensing Dept Dehra Dun 248001 Uttar Pradesh India

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Improving an operational wheat yield model using phenological phase-based normalized difference vegetation index

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INTERNATIONAL JOURNAL OF REMOTE SENSING 2002年第20期23卷 4155-4168页

作者： Boken, VK Shaykewich, CF Univ N Dakota Dept Geog Grand Forks ND 58202 USA Univ Manitoba Dept Soil Sci Winnipeg MB R3T 2N2 Canada

Currently, a model (referred to as a monthly model) employing monthly temperature and precipitation data is used by the Canadian Wheat Board to estimate spring wheat yields for the Canadian Prairies. The model uses a cumulative moisture index as an explanatory variable. In this paper, the performance of the monthly model was improved by first developing a daily model by employing daily, instead of monthly, data for the 1975-1996 period and then by developing a hybrid model which incorporated into the daily model an additional variable derived from the National Oceanic and Atmospheric Administration (NOAA)/Advanced Very High Resolution Radiometer (AVHRR)-based composited normalized difference vegetation index (NDVI) data for the 1987-1996 period. Out of the seven variables derived, two variables-the average NDVI during the heading phenological-phase and the average NDVI during the entire growing season-were found to be the best. The start and the end of the heading phase were estimated using a biometeorological time scale model. The performance of models was tested on five crop districts (1b, 3bn, 4b, 6a, and 9a) of Saskatchewan on the basis of coefficient of determination, R-2. While using 1975-1996 data, the values for R-2 were 0.43, 0.82, 0.73, 0.71 and 0.00 in the case of the daily model as opposed to 0.20, 0.71, 0.57, 0.58, and 0.00 in the case of the monthly model for districts 1b, 3bn, 4b, 6a, and 9a, respectively. While using 1987-1996 data, the values of R 2 were 0.79, 0.96, 0.83, 0.95, and 0.39 in the case of the hybrid model as opposed to 0.13, 0.70, 0.75, 0.50, and 0.00 in the case of the monthly model for districts 1b, 3bn, 4b, 6a, and 9a, respectively. For district 9a, which experiences an adequate supply of soil moisture, the concept of cumulative soil moisture index was not found to hold welt for yield estimation.

关键词： Landsat Moisture index soil water content Hybrid modes Monthly Yield estimation Soil moisture National Oceanic and Atmospheric Administration normalized difference vegetation index

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Remote sensing (normalized difference vegetation index) classification of risk versus minimal risk habitats for human exposure to Ixodes pacificus (Acari: Ixodidae) nymphs in Mendocino County, California

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JOURNAL OF MEDICAL ENTOMOLOGY 2005年第1期42卷 75-81页

作者： Eisen, RJ Eisen, L Lane, RS Univ Calif Berkeley Div Insect Biol Berkeley CA 94720 USA

In California, Ixodes pacificus Cooley & Kohls nymphs have been implicated as the primary bridging vectors to humans of the spirochetal bacterium causing Lyme disease (Borrelia burgdorferi). Because the nymphs typically do not ascend emergent vegetation, risk of human exposure is minimal in grasslands, chaparral, and woodland-grass. Instead, woodlands with a ground cover dominated by leaf litter (hereinafter referred to as woodland-leaf) have emerged as a primary risk habitat for exposure to B. burgdorferi-infected nymphs. As a means of differentiating woodand-leaf habitats from others with minimal risk (e.g., chaparral, grassland, and woodland-grass), we constructed a maximum likelihood model of these habitat types within a 7,711-ha area in southeastern Mendocino County based on the normalized difference vegetation index derived from Landsat 5 Thematic A-rapper imagery (based on a 30 by 30-m pixel size) over four seasons. The overall accuracy of the model to discriminate woodland-leaf, woodland-grass, open grassland, and chaparral was 83.85%, (Kappa coefficient of 0.78). Validation of the accuracy of the model to classify woodland-leaf yielded high values both for producer accuracy (93.33% of validated woodland-leaf pixels correctly classified by the model) and user accuracy (96.55% of model-classified validation pixels correctly categorized as woodland-leaf). Woodland-leaf habitats were found to be highly aggregated within the examined area. In conclusion, our model successfully used remotely sensed data as a predictor of habitats where humans are at risk for Lyme disease in the far-western United States.

关键词： Ixodes pacificus Landsat normalized difference vegetation index remote sensing Lyme disease

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On the relationship between normalized difference vegetation index and land surface temperature: MODIS-based analysis in a semi-arid to arid environment

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GEOCARTO INTERNATIONAL 2021年第10期36卷 1117-1135页

作者： Jaber, Salahuddin M. Hashemite Univ Fac Nat Resources & Environm Dept Water Management & Environm Zarqa Jordan

This work focused on studying the relationships between normalized difference vegetation index (NDVI) and daytime and nighttime Land Surface Temperature (LST) in winter, spring, summer and fall and investigating the effects of land cover on these variables in Jordan, which represents a typical semi-arid to arid environment. Using MODIS-based data for the year 2017, multiple procedures were applied: one-way analysis of variance followed by comparison between means, Pearson correlation coefficient, global Moran's index, simple linear regression, second-order polynomial regression, recursive-partitioning regression and geographically weighted regression. The results showed that land cover explained fair amount of the variability in NDVI but small amount of the variability in daytime and nighttime LST. In addition, an inverted surface urban heat island pattern was observed in daytime. Finally, applying different regression procedures produced different perspectives about the complex and variable relationships between daytime and nighttime LST and NDVI in different seasons.

关键词： normalized difference vegetation index land surface temperature MODIS semi-arid to arid environments modeling

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Analysis of genotypic variation for normalized difference vegetation index and its relationship with grain yield in winter wheat under terminal heat stress

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PLANT BREEDING 2012年第6期131卷 716-721页

作者： Hazratkulova, Shahnoza Sharma, Ram C. Alikulov, Safar Islomov, Sarvar Yuldashev, Tulkin Ziyaev, Zafar Khalikulov, Zakir Ziyadullaev, Zokhid Turok, Jozef ICARDA CAC Reg Program Tashkent Uzbekistan Kashkadarya Res Inst Grain Breeding & Seed Prod Karshi Uzbekistan Uzbek Res Inst Plant Ind Kibray Uzbekistan

normalized difference vegetation index (NDVI), which is a measure of leaf greenness (chlorophyll content), is considered to be correlated with crop productivity. This study was conducted to examine genotypic variations for NDVI at different growth stages and its relationship to yield in winter wheat under terminal heat stress. Thirty winter wheat genotypes were evaluated at two locations in 20092010 and 20102011 in Uzbekistan. The NDVI was recorded at booting, heading, milk and dough stages. The wheat genotypes differed significantly for NDVI at each stage. Grain yield ranged from 3.9 to 6.1 t/ha. Wheat genotypes differed in per cent decline in NDVI from booting to dough stage. However, several high-yielding genotypes maintained higher NDVI than low-yielding genotypes when heat stress was evident. The findings suggest change in NDVI during heat stress could be a measure of tolerance. The positive correlation of NDVI with grain yield suggests that it could be used as an indirect selection criterion for identifying physiologically superior, high-yielding wheat lines under terminal heat stress.

关键词： correlation genotypic variation grain yield growth stage normalized difference vegetation index wheat

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Relationship of cotton nitrogen and yield with normalized difference vegetation index and plant height

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NUTRIENT CYCLING IN AGROECOSYSTEMS 2014年第2期100卷 147-160页

作者： Zhou, Guisu Yin, Xinhua Yunnan Agr Univ Coll Tobacco Sci & Technol Kunming 650201 Peoples R China Univ Tennessee Dept Plant Sci Jackson TN 38301 USA

The strength of the associations of cotton (Gossypium hirsutum L.) yield and N nutrition with integrated normalized difference vegetation index (NDVI) and plant height measurements has been scarcely documented. The objective of this investigation was to compare the strength in terms of determination coefficient (R-2) among the associations of cotton yield and leaf N concentration with integrated and respective NDVI and plant height measurements taken at key growth stages. A field experiment was carried out on no-till cotton at Jackson and Milan in Tennessee during 2008-2010. Six N treatments of 0, 45, 90, 135, 179, and 224 kg N ha(-1) were implemented in a randomized complete block design with four replicates for all site years. Regressions of lint yield with NDVI x plant height and NDVI + plant height were sometimes stronger than those of lint yield with NDVI alone. Associations of leaf N concentration with NDVI x plant height and NDVI + plant height were similar to or variably stronger than those of leaf N with NDVI alone. Regressions of lint yield and leaf N with NDVI x plant height or NDVI + plant height were generally similar to those of lint yield and leaf N with plant height alone. Utilization of integrated NDVI and plant height measurements to predict cotton yield and/or assess N nutrition has variable advantages over the use of NDVI alone. Both integrated and respective NDVI and plant height measurements are more appropriate to be used to predict cotton yield than to assess N nutrition.

关键词： Regression Cotton Yield Leaf nitrogen normalized difference vegetation index Plant height

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Dependence of the normalized difference vegetation index Level on the Spatial Structure of the Landscape and Its Time Variability Using the Example of the West End of the Crimean Peninsula (Tarkhankut Peninsula)

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IZVESTIYA ATMOSPHERIC AND OCEANIC PHYSICS 2021年第12期57卷 1586-1595页

作者： Shadchinov, S. M. Moscow MV Lomonosov State Univ Moscow 119991 Russia

In this paper, we solve the problem of assessing the dependence of the functioning of the landscape on its spatial structure. The object of research is the relation between the vegetation phytomass expressed by normalized difference vegetation index values and morphometric values calculated using a digital elevation model. The sensitivity of the vegetation cover to the characteristics of the relief for the Black Sea steppes of the Tarkhankut Peninsula was estimated using multiregression analysis. The dynamics of the normalized regression coefficient from 1998 to 2019 was plotted. Analysis of climatic data revealed that the dryness of the year is reflected in the coefficient values. In 2007, which was the driest year, the phytomass sensitivity to geomorphological conditions noticeably decreased. Analysis of the plots showed that the interseasonal variability of the vegetation sensitivity to the relief is greater than the interannual variability. An increase in the relation between the vegetation biomass and the terrain ruggedness from the beginning to the end of the growing season was also revealed.

关键词： steppe landscape spatial structure normalized difference vegetation index phytomass dynamics multiple regression Tarkhankut Peninsula

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The relationship between the normalized difference vegetation index and drought indices in the South Central United States

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NATURAL HAZARDS 2019年第2期96卷 791-808页

作者： Bushra, Nazla Rohli, Robert V. Lam, Nina S. N. Zou, Lei Mostafiz, Rubayet Bin Mihunov, Volodymyr Louisiana State Univ Coll Coast & Environm Dept Oceanog & Coastal Sci Baton Rouge LA 70803 USA Louisiana State Univ Coll Coast & Environm Dept Environm Sci Baton Rouge LA 70803 USA

Drought indices are useful for quantifying drought severity and have shown mixed success as an indicator of drought damage and biophysical dryness. While spatial downscaling of drought indicators from the climate divisional level to the county level has been conducted successfully in previous work, little research to date has attempted to upscale remotely sensed biophysical indicators to match the downscaled drought indices. This upscaling is important because drought damage and indices are often reported at a coarser scale than the biophysical indicators provide. This research upscales National Oceanic and Atmospheric Administration's Advanced Very High Resolution Radiometer sensor-acquired normalized difference vegetation index (NDVI) data to produce a county-level biophysical drought index, for a five-state region of the South Central United States. The county-level NDVI is then correlated with the downscaled drought indices for assessing the degree to which the biophysical data match well-documented drought indicators. Results suggest that the Palmer Drought Severity index and Palmer Hydrologic Drought index are effective indicators of biophysical drought in much of the arid western part of the study area and in larger swaths of the study area in summer. In nearly all cases except for autumn months, correlations are weakest in the ecotones, with significant negative correlations in the humid eastern part of the study area. Results generally corroborate the findings of recent research that correlations between drought indices and biophysical drought vary spatially. As long-lead climate forecasts continue to improve, these results can assist environmental planners in preparing for the impacts of drought.

关键词： Drought Statistical upscaling Palmer Drought Severity index Palmer Hydrologic Drought index normalized difference vegetation index South Central United States

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Temporal variations in the usefulness of normalized difference vegetation index as a predictor for Ixodes ricinus (Acari: Ixodidae) in a Borrelia lusitaniae focus in Tuscany, central Italy

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JOURNAL OF MEDICAL ENTOMOLOGY 2008年第3期45卷 547-555页

作者： Bisanzio, Donal Amore, Giuseppina Ragagli, Charlotte Tomassone, Laura Bertolotti, Luigi Mannelli, Alessandro Univ Turin Fac Med Vet Dipartimento Produzioni Animal I-10095 Grugliasco TO Italy

Host-seeking ticks were collected during monthly dragging sessions from November 2004 through October 2006 in Tuscany, central Italy. normalized difference vegetation index (NDVI), which was calculated from Landsat ETM+ 7 remote sensing data recorded in August 2001, was significantly correlated with numbers of host-seeking immature Ixodes ricinus L. (Acari: Ixodidae) during periods of relatively low rainfall such as summer 2005 (Spearman's rho = 0.78, P < 0.001 for nymphs in July) and to a lower extent in spring-summer 2006. In spring 2005, when rainfall was relatively high, the correlation was weak and not statistically significant. Generalized estimating equations (GEEs), taking into account repeated sampling of the same dragging sites, were used to model the effects of NDVI and season on counts of host-seeking I. ricinus nymphs. Seasonal variations of the effect of NDVI yielded a significant NDVI-by-season interaction in the first year of the study (November 2004-October 2005), but not in the second year (November 2005-October 2006) when there was a 2.5-fold increase of the number of nymphs per 100-m dragging for every 0.1 unit increase in NDVI (95% confidence interval = 1.6, 3.0). Risk maps that were obtained based on GEE results confirmed that the predicted number of I. ricinus nymphs per 100 m was relatively homogeneous through the study area during the 2005 spring peak of activity. Conversely, in 2006, the predicted abundance of nymphs was greater in moist bottomland habitat (characterized by high NDVI) than in dry, typically Mediterranean, upland habitat.

关键词： Ixodes ricinus normalized difference vegetation index ticks Italy

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