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Coconut Inventory Activities in the Pacific ?. Wolf Forstreuter. Coconut Resource Known ?. “Kiribati has 3,827,913 coconut palms” Believable?. Palm Resource Mapping with VHR Satellite Images. Separation of coconut palm from other vegetation possible Density stratification is possible
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Coconut Inventory Activities in the Pacific ? Wolf Forstreuter
Coconut Resource Known ? • “Kiribati has 3,827,913 coconut palms” • Believable?
Palm Resource Mappingwith VHR Satellite Images • Separation of coconut palm from other vegetation possible • Density stratification is possible • Counting is possible in scattered and semi dense stands with 95% accuracy (dense underestimation) • Field work necessary but reduced to statistical minimum
Display VHR Image Data Texture of pan-sharpened VHR image data allows to separate palm and natural forest
Density Classes • Scattered 25 – 50 palms / hectare • Semi dense 50 – 150 palms / hectare • Dense > 150 palms / hectare
Delineation of Palm Density 50 x 50 m grid helps interpretation
Selection of Sample Plots for Coconut Palm Counting Select are only plots that are fully covered by one stratum Randomly selection of about 20 % plots Counting palms / plot
Counting Palms in Plots • Placing a dot on top of every visible palm • Digital overlay with grid and counting in MapInfo (GIS software) dots per grid cell • Transfer to Access
Counting in MapInfo SQL Result MapInfo automatically counts the number of palms within the plots using SQL select
Analysis in Access • Sum • Min • Max • Mean • No Plots • Area plots • Area Stratum • (Pot. No. Plots)
Mapping at SPC and PIC SPC-SOPAC Fiji Agriculture Kiribati Environment Kiribati
Field Sample Plots Needed • Counting palms / hectare in dense stands • Counting amount of hybrids • Estimation coconut production • Recording extent of diseases • Estimation of palm age • Estimation of timber volume (diametre and height) 50 – 100% under estimation of palms / hectare in dense stands
Field Plots • 40 x 40 m in scattered and semi dense stands • Selection of image sample plots • GPS assistance for location identification in the field
Age / Height Measurement • Length of 11 leave scares in cm • Height of palm • Distance to bottom • Angle to bottom • Angle to top
Fertility • Number of coconuts / bunch • Three oldest bunches counted • Average calculated
Diseases Top: Stick insect Right: Rhinoceros beetle
Timber Volume • DBH • Height • Form factor • Timber factor
Harvesting Coconuts It is uneconomic to search for a coconut ! It is uneconomic to carry more than 300m !
Distance to Road • Create buffer zones around tracks and roads • Overlay over stratified area • Recalculate productive area
Remote sensing, GIS and GPS technology provide new avenues for coconut resource inventories • Utilising these technologies enables quantitative estimation of available resource Thanks