HI-CROP Web Mapper
By Jacob Gross
The Hawaii Cropland Rating and Optimization Planning (HI-CROP) Web Mapper displays crop suitability maps for the Island of Hawaii. The cropland rating was determined from average monthly or annual rainfall, average minimum and maximum monthly temperature, soil pH, soil depth, soil drainage class, and slope.
Each crop available within the HI-CROP Web Mapper contains an overall rating map. The overall rating map is constructed using a spatial overlay that combines all criteria and selects the final rating based on the score of the most limiting factor. Scores for individual criterion are available by clicking on a desired location. Monthly crop suitability is also evaluated within the HI-CROP Model in order to determine the optimum month to begin planting a selected crop. Crops with growing cycles shorter than twelve months can be toggled to display optimum planting periods.
These maps were created using ESRI ArcGIS geoprocessing tools and custom functions written in Python programming language. The entire procedure used to create the cropland rating maps is stored within the HI-CROP Model (See HI-CROP Model section below).
The HI-CROP Model is designed to be adaptable to accommodate a variety of crop types including both established crops currently grown in Hawaii and new crops that have yet to be explored commercially in Hawaii. Additionally, the HI-CROP Model easily accommodates new spatial datasets of environmental conditions or updated crop requirement parameters (see sections below for sources of present environmental conditions and crop requirements).
Sources of Present Environmental Conditions
Cropland suitability rating is determined by the degree in which the measured natural environmental conditions of a given location match the ecological requirements of a specific crop. The six environmental criteria evaluated in the HI-CROP Model are listed below along with their data sources and units of measurement.
|2013 Rainfall Atlas of Hawaii||The mean monthly rainfall values originate from a 30-year base period from 1978-2007. Original raster files were created at ~250 m resolution using the WGS84 Datum. See Giambelluca et al. (2013) for more information. Data transformed and resampled to 100 m resolution.|
|PRISM Climate Group||Monthly average interpolated temperature surfaces from 1971-2000. Original resolution is in 15 arc second cells (approximately 500 m in Hawaii). Data transformed and resampled to 100 m resolution.|
|NOAA's National Ocean Service (NOS), National Centers for Coastal Ocean Science (NCCOS)||Dataset derived from USGS 7.5' DEM Quads for the main 8 Hawaiian Islands. Original resolution is in 10m. Data transformed and resampled to 100m resolution. Calculated slope using slope command in ArcGIS.|
|Natural Resource Conservation Service (NRCS) Web Soils Survey (WSS) Soil Data Viewer (SDV) 6.0||
Soil pH was calculated in SDV using the weighted average of surface layer conditions.
Soil Depth was calculated in SDV using the Depth to any soil restrictive layer and was aggregated amongst soil components using the weighted average method.
Drainage class was converted to a numerical scale (2 = very poorly drained, 8 = excessively drained). Soil components were aggregated using the Dominant Condition Method in SDV.
Vector datasets created by Soil Data Viewer were converted to Raster datasets using “Polygon to Raster” Tool in ArcGIS.
Sources of Crop Requirements
The Food and Agriculture Organization (FAO) of the United Nations maintains a searchable online database of crops called Ecocrop (www.ecocrop.fao.org). Ecocrop includes 2,568 crop species along with its associated environmental requirements. The structure of the Ecocrop database provided a useful starting point from which to map cropland suitability in Hawaii. In general, crop environmental requirements for the HI-CROP Model are initially based on Ecocrop’s reported minimum and maximum values (crop parameters). If specific crop environmental requirements are available for Hawaii, then the Ecocrop values are replaced with the Hawaii specific values. When available, expert opinion is also used to adjust crop parameters.
Click the files below to see example crop parameters:
Figure 1. Example fuzzy membership set illustrating how the cropland rating score varies with mean annual rainfall.
The land evaluation method used in the HI-CROP model was adapted from(Ramirez-Villegas et al., 2013). Each crop evaluated has an optimal range (OPTmin-OPTmax) and an absolute range (ABSmin-ABSmax) associated with a particular criterion (e.g. Rainfall, Temperature, etc.). A linear fuzzy membership is calculated using the absolute and optimal ranges (see Figure 1). If the observed environmental condition is within the optimum range for the crop the location is assigned a score of “100” for that particular crop and criterion. If the observed environmental condition is outside the absolute range the location receives a score of “0”. Environmental conditions observed between the absolute and optimal values result in a score that is weighted by its numerical distance from the optimal range.
HI-CROP Web Mapper data have not been validated due to unavailable sources for comparison. Direct measurements of cropland suitability such as crop yields are difficult to obtain from private landowners. Additionally, yields vary greatly due to planting density, harvesting methods, and farming techniques. HI-CROP maps are created based on natural site conditions, therefore, any yield data used for validation would need to be corrected against the soil and water amendments that have been added prior to the harvesting of the crop.
The information contained in these data is dynamic and may change over time. The data are not better than the original sources from which they were derived. It is the responsibility of the data user to use the data appropriately and consistent within the limitations of geospatial data in general and these data in particular.
No warranty is given, expressed, or implied, as to the accuracy, reliability, or completeness of these data. The geoportal project shall not be held liable for improper or incorrect use of the data described and/or contained herein.
Map (full screen map)
Agribusiness Development Corporation/Hawaii State Department of Agriculture
Jacob Gross, Nathan Dorman, Tomoaki Miura, Jonathan Deenik, John Yanagida, Russell Yost, Joshua Silva, Elsie Kawahara
Coffee Expert Opinion:
Giambelluca, T. W., Chen, Q., Frazier, A. G., Price, J. P., Chen, Y., Chu, J., Eischeid, J. K., and Delparte, D. (2013). Online Rainfall Atlas of Hawaii. Bull. Amer. Meteor. Soc. 94, 313-316.
Ramirez-Villegas, J., Jarvis, A., and Laderach, P. (2013). Empirical approaches for assessing impacts of climate change on agriculture: The EcoCrop model and a case study with grain sorghum. Agricultural and forest meteorology 170, 67-78.