Assessment of the Spectral Characteristics of Different Physiological Stages of Some Olive cvs and Its Relation with Productivity

Amany F Elwesemy,Ayman F Abohadid,Nazmy A Abdelghany,Mohamed A Aboelghar

doi:10.23953/cloud.ijarsg.45

Abstract

Remote sensing satellite imagery is the tool to obtain synoptic, multi-temporal, dynamic and timely efficient information about any target on Earth. The main objective of the current study is to use remote sensing satellite data and field spectral reflectance measurements to identify the spectral pattern of the different cultivars of olives and to statistically correlate this spectral reflectance pattern with crop productivity. The study was carried out in El-Beheira governorate (Wadi El Natrun) city during the whole year of 2014. The three observed varieties were Picual, Manzanillo and Kalamata. Measurements were carried out for five growth stages: dormancy stage, flowering stage, fruit sat stage, mature stage and ripening stage. The spectral reflectance pattern for each cultivar through the different growth stages was identified. Then, seven vegetation indices (normalized difference vegetation index (NDVI), modified chlorophyll absorption ration index (MCARI), triangular vegetation index (TVI), modified chlorophyll absorption ration index-1 (MCARI-1), modified chlorophyll absorption ration index-2 (MCARI-2), modified triangular vegetation index-2 (MTVI2) and chlorophyll index (CI)) were calculated through the five growth stages for each cultivar and then were observed as estimators for crop yield modeling. Analysis of the result based on the comparison of the correlation coefficient (r 2 ) for all generated models, the target is to identify the optimal vegetation index and the optimal growth stage to predict yield for each variety. Generally, Manzanillo variety showed the highest reflectance followed by Picual and Kalamata. The result showed that the highest (r 2 ) was with the two cultivars Picual and Kalamata during mature stage, while the highest (r 2 ) was with cultivar Manzanillo during fruit sat stage. While the lowest (r 2 ) was found during dormancy stage for the three cultivars.

Highlights

Olive (Oleaeuropaea L.) is one of the most important crops in Egypt
Bare fore optic 25 degrees used for outdoor measurements resulting circular field of view with 3 cm diameter as measurements were taken at 5 cm height in nadir position (90 degrees) over the measured plants
The spectral zones for the three cvs showed that the highest spectral reflectance was in near infra-red infrared spectral zone (700–1300 nm), relatively low reflectance in the spectral zone (1450–1800 nm) whiles the lower reflectance was found in the spectral zone (1950-2300 nm)

Summary

Introduction

Olive (Oleaeuropaea L.) is one of the most important crops in Egypt. In 2014, Olive in Egypt occupies 82047.63 hectare with a total product of 563070 tons as of 2014. The top olive producers’ areas in Egypt are the west coast, the province of Faiyum, Siwa Oasis, northern Sinai and Wadi El Natrun. Because of the importance of Olive cultivation for national economy, there is a high need to facilitate using remote sensing techniques in monitoring and predicting the yield of olive through remotely sensed statistical empirical models. Remote sensing is the science to detect, measure, record and analyze energy in a selected portion of the electromagnetic spectrum. In particular, multispectral visible and Infra-Red (IR) reflectance and emission can provide an instantaneous, non-destructive, and quantitative assessment of crops ability to intercept radiation and photosynthesize [1]

Objectives

Methods

Results

Conclusion