Land Cover Classification of Complex Agroecosystems in the Non-Protected Highlands of the Galapagos Islands
"> Figure 1
<p>Study area. Each of the inhabited islands has a designated agricultural zone. The map above shows the geographical location of the agricultural zones (blue outline), and the panels below show a detail of each agricultural zone with cloudless PlanetScope images.</p> "> Figure 2
<p>Category hierarchy used for land cover classification of Galapagos agroecosystems.</p> "> Figure 3
<p>Workflow overview for land cover classification.</p> "> Figure 4
<p>Comparison of spectral bands between Sentinel-2 and PlanetScope satellites. The axes depict the wavelength in nanometers and the terrestrial atmospheric transmission (grey) in percent (adapted from NASA, <a href="https://landsat.gsfc.nasa.gov/sentinel-2a-launches-our-compliments-our-complements/" target="_blank">https://landsat.gsfc.nasa.gov/sentinel-2a-launches-our-compliments-our-complements/</a>).</p> "> Figure 5
<p>Footprint of UAV flights, GPS control points, and selected training samples for land cover classification of humid highlands and agricultural zones of the Galapagos.</p> "> Figure 6
<p>Land cover classification of the agricultural areas and surrounding humid highlands of the Galapagos.</p> "> Figure A1
<p>Distribution of native ecosystems in and around the agricultural zones of the inhabited islands of the Galapagos.</p> "> Figure A2
<p>Distribution of invasive vegetation in and around the agricultural zones of the inhabited islands of the Galapagos.</p> "> Figure A3
<p>Distribution of pastures in and around the agricultural zones of the inhabited islands of the Galapagos.</p> "> Figure A4
<p>Distribution of food crops in and around the agricultural zones of the inhabited islands of the Galapagos.</p> "> Figure A5
<p>Distribution of mixed forest and pioneer vegetation cover in and around the agricultural zones of the inhabited islands of the Galapagos.</p> ">
Abstract
:1. Introduction
1.1. The Humid Highlands of the Galapagos and Their Value
1.2. Remote Sensing of Island Agroecosystems
1.3. Past and Present Efforts to Map the Humid Highlands and Agroecosystems of the Galapagos Using Remote Sensing
1.4. Objectives
- Develop a classification methodology, using remote sensing, specifically in complex agroecosystem landscapes.
- Identify regions of remaining native forests in and near the agricultural zone.
- Identify the distribution of invasive plant species like Psidium guajava, Rubus niveus, Zygsigum jambos, and Pennisetum purpureum that threaten agricultural lands and adjacent protected areas.
- Identify the distribution of Erythrina smithiana living fences in Santa Cruz, which might act as an obstacle for migrating tortoise populations.
- Identify the distribution of economically significant agricultural land cover like cattle ranching pastures, annual crops, tree crops, and cash crops, such as coffee.
2. Materials and Methods
2.1. Study Area
2.2. Preliminary Definition of Land Cover Units
2.3. Land Cover Classification
2.3.1. Data Acquisition
Multispectral Data
Topographical Data
Unmanned Aerial Images and GPS Control Points
2.3.2. Image Pre-Processing
2.3.3. Image Fusion
2.3.4. Vegetation Indices
2.3.5. Object-Oriented Classification with RandomForest
Segmentation
Training Data Sample
Random Forest Classification
2.3.6. Verification
2.3.7. Validation
3. Results
3.1. Object Oriented Classification with Random Forest
3.2. Spatial Coverage and Distribution of Land Cover Categories
3.3. Validation
4. Discussion
4.1. Methodology and Sources of Error
4.2. Vegetation Cover Abundance and Distribution
4.3. Comparing and Combining Results with Existing Datasets
4.4. Broader Significance
4.5. Next Steps
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
Appendix A. Land Cover Classification and Validation Results
Land Cover | Santa Cruz | |||||
---|---|---|---|---|---|---|
Agricultural Area | Buffer Zone | Total | ||||
Ha | % | Ha | % | Ha | % | |
Bare Ground | 12.62 | 0.11 | 10.62 | 0.06 | 23.24 | 0.08 |
Built Environment | 116.77 | 1.02 | 15.21 | 0.08 | 131.98 | 0.44 |
Cedrela—Cedar | 726.56 | 6.35 | 2372.21 | 12.97 | 3098.77 | 10.42 |
Cinchona—Quinine | 17.42 | 0.15 | 48.25 | 0.26 | 65.67 | 0.22 |
Coffea—Coffee | 639.97 | 5.59 | 7.49 | 0.04 | 647.45 | 2.18 |
Cultivated Grass | 1593.73 | 13.93 | 32.01 | 0.18 | 1625.73 | 5.47 |
Deciduous Forest | 123.74 | 1.08 | 4825.64 | 26.39 | 4949.38 | 16.65 |
Evergreen Forest and Shrubland | 659.53 | 5.77 | 1782.73 | 9.75 | 2442.26 | 8.22 |
Evergreen Seasonal Forest | 580.60 | 5.08 | 7123.00 | 38.95 | 7703.60 | 25.92 |
Freshwater | 22.47 | 0.20 | 2.22 | 0.01 | 24.70 | 0.08 |
Humid Tallgrass | 136.54 | 1.19 | 334.58 | 1.83 | 471.12 | 1.58 |
Mixed Forest | 259.40 | 2.27 | 906.64 | 4.96 | 1166.05 | 3.92 |
Pennisetum—Elephant Grass | 53.66 | 0.47 | 121.43 | 0.66 | 175.09 | 0.59 |
Permanent Crops | 1531.34 | 13.39 | 106.09 | 0.58 | 1637.42 | 5.51 |
Pioneer | 831.12 | 7.27 | 41.77 | 0.23 | 872.88 | 2.94 |
Psidium—Guava | 1646.79 | 14.40 | 459.09 | 2.51 | 2105.89 | 7.08 |
Rubus—BlackBerry | 29.68 | 0.26 | 60.53 | 0.33 | 90.21 | 0.30 |
Silvopasture | 2078.94 | 18.17 | 32.23 | 0.18 | 2111.17 | 7.10 |
Syzygium—Pomarrosa | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
Transitory Crops | 377.83 | 3.30 | 5.36 | 0.03 | 383.19 | 1.29 |
Total | 11,438.70 | 100.00 | 18,287.11 | 100.00 | 29,725.81 | 100.00 |
Land Cover | San Cristobal | |||||
---|---|---|---|---|---|---|
Agricultural Area | Buffer Zone | Total | ||||
Ha | % | Ha | % | Ha | % | |
Bare Ground | 3.33 | 0.04 | 141.00 | 1.76 | 144.34 | 0.88 |
Built Environment | 111.81 | 1.34 | 13.97 | 0.17 | 125.78 | 0.77 |
Cedrela—Cedar | 130.76 | 1.57 | 3.00 | 0.04 | 133.75 | 0.82 |
Cinchona—Quinine | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
Coffea—Coffee | 191.48 | 2.30 | 9.89 | 0.12 | 201.37 | 1.23 |
Cultivated Grass | 290.52 | 3.48 | 34.78 | 0.43 | 325.30 | 1.99 |
Deciduous Forest | 107.60 | 1.29 | 3283.88 | 40.97 | 3391.48 | 20.73 |
Evergreen Forest and Shrubland | 1648.26 | 19.76 | 552.38 | 6.89 | 2200.63 | 13.45 |
Evergreen Seasonal Forest | 704.05 | 8.44 | 3145.39 | 39.24 | 3849.44 | 23.53 |
Freshwater | 5.11 | 0.06 | 0.61 | 0.01 | 5.72 | 0.03 |
Humid Tallgrass | 75.71 | 0.91 | 0.00 | 0.00 | 75.71 | 0.46 |
Mixed Forest | 981.58 | 11.77 | 466.49 | 5.82 | 1448.07 | 8.85 |
Pennisetum—Elephant Grass | 19.48 | 0.23 | 8.94 | 0.11 | 28.42 | 0.17 |
Permanent Crops | 673.30 | 8.07 | 64.57 | 0.81 | 737.87 | 4.51 |
Pioneer | 194.27 | 2.33 | 1.94 | 0.02 | 196.21 | 1.20 |
Psidium—Guava | 1952.21 | 23.40 | 228.14 | 2.85 | 2180.35 | 13.33 |
Rubus—BlackBerry | 289.75 | 3.47 | 20.22 | 0.25 | 309.97 | 1.90 |
Silvopasture | 480.09 | 5.76 | 23.95 | 0.30 | 504.04 | 3.08 |
Syzygium—Pomarrosa | 374.37 | 4.49 | 9.72 | 0.12 | 384.09 | 2.35 |
Transitory Crops | 107.32 | 1.29 | 7.17 | 0.09 | 114.49 | 0.70 |
Total | 8340.99 | 100.00 | 8016.04 | 100.00 | 16,357.03 | 100.00 |
Land Cover | Isabela | |||||
---|---|---|---|---|---|---|
Agricultural Area | Buffer Zone | Total | ||||
Ha | % | Ha | % | Ha | % | |
Bare Ground | 0.72 | 0.01 | 356.17 | 4.73 | 356.89 | 2.80 |
Built Environment | 24.83 | 0.48 | 2.71 | 0.04 | 27.54 | 0.22 |
Cedrela—Cedar | 471.34 | 9.05 | 185.60 | 2.46 | 656.94 | 5.16 |
Cinchona—Quinine | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
Coffea—Coffee | 113.41 | 2.18 | 24.58 | 0.33 | 137.99 | 1.08 |
Cultivated Grass | 512.09 | 9.83 | 52.16 | 0.69 | 564.26 | 4.43 |
Deciduous Forest | 35.33 | 0.68 | 337.23 | 4.48 | 372.56 | 2.92 |
Evergreen Forest and Shrubland | 120.36 | 2.31 | 124.55 | 1.65 | 244.91 | 1.92 |
Evergreen Seasonal Forest | 344.71 | 6.62 | 2440.90 | 32.42 | 2785.61 | 21.87 |
Freshwater | 0.71 | 0.01 | 4.64 | 0.06 | 5.35 | 0.04 |
Humid Tallgrass | 157.60 | 3.02 | 652.98 | 8.67 | 810.58 | 6.36 |
Mixed Forest | 599.48 | 11.51 | 1282.43 | 17.03 | 1881.91 | 14.77 |
Pennisetum—Elephant Grass | 30.71 | 0.59 | 401.17 | 5.33 | 431.88 | 3.39 |
Permanent Crops | 741.13 | 14.22 | 57.14 | 0.76 | 798.27 | 6.27 |
Pioneer | 21.03 | 0.40 | 19.84 | 0.26 | 40.87 | 0.32 |
Psidium—Guava | 1304.19 | 25.03 | 1543.43 | 20.50 | 2847.61 | 22.35 |
Rubu—BlackBerry | 5.95 | 0.11 | 0.00 | 0.00 | 5.95 | 0.05 |
Silvopasture | 504.38 | 9.68 | 13.85 | 0.18 | 518.23 | 4.07 |
Syzygium—Pomarrosa | 59.67 | 1.15 | 19.36 | 0.26 | 79.03 | 0.62 |
Transitory Crops | 162.68 | 3.12 | 10.59 | 0.14 | 173.27 | 1.36 |
Total | 5210.30 | 100.00 | 7529.33 | 100.00 | 12,739.64 | 100.00 |
Land Cover | Floreana | |||||
---|---|---|---|---|---|---|
Agricultural Area | Buffer Zone | Total | ||||
Ha | % | Ha | % | Ha | % | |
Bare Ground | 1.96 | 0.72 | 5.25 | 0.36 | 7.20 | 0.42 |
Built Environment | 5.63 | 2.08 | 3.93 | 0.27 | 9.56 | 0.55 |
Cedrela—Cedar | 20.96 | 7.73 | 13.73 | 0.94 | 34.70 | 2.00 |
Cinchona—Quinine | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
Coffea—Coffee | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
Cultivated Grass | 6.14 | 2.27 | 0.10 | 0.01 | 6.24 | 0.36 |
Deciduous Forest | 2.30 | 0.85 | 95.84 | 6.55 | 98.14 | 5.66 |
Evergreen Forest and Shrubland | 0.74 | 0.27 | 278.18 | 19.02 | 278.92 | 16.09 |
Evergreen Seasonal Forest | 12.77 | 4.71 | 670.68 | 45.85 | 683.45 | 39.42 |
Freshwater | 1.10 | 0.40 | 0.17 | 0.01 | 1.26 | 0.07 |
Humid Tallgrass | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
Mixed Forest | 36.70 | 13.54 | 174.97 | 11.96 | 211.67 | 12.21 |
Pennisetum—Elephant Grass | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
Permanent Crops | 23.62 | 8.72 | 4.30 | 0.29 | 27.92 | 1.61 |
Pioneer | 2.48 | 0.91 | 6.46 | 0.44 | 8.94 | 0.52 |
Psidium—Guava | 55.67 | 20.54 | 190.28 | 13.01 | 245.95 | 14.19 |
Rubus—BlackBerry | 0.00 | 0.00 | 0.67 | 0.05 | 0.67 | 0.04 |
Silvopasture | 50.34 | 18.58 | 12.84 | 0.88 | 63.18 | 3.64 |
Syzygium-Pomarrosa | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 |
Transitory Crops | 50.60 | 18.67 | 5.22 | 0.36 | 55.82 | 3.22 |
Total | 271.01 | 100.00 | 1462.62 | 100.00 | 1733.63 | 100.00 |
Category | KIA | AUC |
---|---|---|
Bare Ground | 0.2711 | 0.386 |
Built Environment | 0.5159 | 0.685 |
Cedrela—Cedar | 0.8249 | 0.905 |
Coffea—Coffee | 0.1927 | 0.676 |
Cultivated Grass | 0.607 | 0.817 |
Deciduous Forest | 0.9822 | 0.872 |
Syzygium—Pomarosa | 0.9952 | 0.879 |
Evergreen Forest and Shrubland | 0.9884 | 0.882 |
Evergreen Seasonal Forest and Shrubland | 0.7328 | 0.747 |
Freshwater | 0.3397 | 0.38 |
Mixed Forest | 0.6876 | 0.781 |
Pennisetum—Elephant Grass | 1 | 0.888 |
Permanent Crops | 0.5727 | 0.752 |
Pioneer | 0.2223 | 0.314 |
Psidium—Guava | 0.7816 | 0.846 |
Rubus—Blackberry | 0.4167 | 0.603 |
Silvopasture | 0.6582 | 0.708 |
Transitory Crops | 0.4461 | 0.628 |
Appendix B. Thematic Maps
Appendix C. Land Cover Classification for the Entire Province
Category | Land Cover Classes | Protected Area [35] | Agricultural Area | Total | % |
---|---|---|---|---|---|
Forest and Shrub | Evergreen forest and shrubland | 30,788.9 | 2425.8 | 33,214.7 | 4.2 |
Evergreen seasonal forest and shrubland | 60,887.7 | 1640.9 | 62,528.6 | 7.9 | |
Coastal humid forest and shrubland | 1377.5 | 1377.5 | 0.2 | ||
Deciduous forest | 262,527 | 268.8 | 262,795.8 | 33.0 | |
Deciduous shrubland | 28,258 | 28,258.0 | 3.5 | ||
Herbaceuos vegetation | Humid Tallgrass | 4477.5 | 369.7 | 4847.2 | 0.6 |
Highland deciduous tallgrass | 6922.6 | 6922.6 | 0.9 | ||
Deciduous tallgrass | 17,137.4 | 17,137.4 | 2.2 | ||
Mangroves | Mangrove forest | 1470.4 | 1470.4 | 0.2 | |
Invasive Species | Cedrela—cedar | 1977.4 | 1349.4 | 3326.8 | 0.4 |
Mixed | 1142.1 | 1875.4 | 3017.5 | 0.4 | |
Rubus—blackberry | 495.1 | 324.8 | 819.9 | 0.1 | |
Pennisetum—grass | 2871.7 | 103.8 | 2975.5 | 0.4 | |
Cinchona—quinine | 61 | 17.4 | 78.4 | 0.0 | |
Psidium—guava | 10,312.6 | 4955.2 | 15,267.8 | 1.9 | |
Syzygium—Pomarrosa | 433.4 | 433.4 | 0.1 | ||
Rocky outcrop | Recent lavas | 252,273.3 | 252,273.3 | 31.7 | |
Old lavas | 87,914.8 | 18.6 | 87,933.4 | 11.0 | |
Agricultural Areas | Coffea—Coffee | 944.5 | 944.5 | 0.1 | |
Cultivated Grass | 2402.0 | 2402.0 | 0.3 | ||
Silvopastures | 3112.9 | 3112.9 | 0.4 | ||
Transitory Crops | 698.2 | 698.2 | 0.1 | ||
Permanent Crops | 2968.1 | 2968.1 | 0.4 | ||
Other | Urban settings | 550.7 | 258.8 | 809.5 | 0.1 |
Water | 705.7 | 29.4 | 735.1 | 0.1 | |
Total | 772,151.4 | 24,197.17 | 796,348.6 | 100 |
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Source | Sensor | Spatial Resolution | Spectral Resolution | Year Images Collected | Agricultural Zone Visibility |
---|---|---|---|---|---|
CLIRSEN and TNC, 2006 | SPOT 4 | 20 m | Visible, SWIR | 2000 | highly obscured by clouds |
Landsat 5 | 30 m | Visible, NIR, SWIR | 2000 | ||
SIGTIERRAS 2010 | Orthophotos | 0.5 m | Visible | 2009 | Yes |
Rivas-Torres et al., 2018 | Landsat 8 | 30 m | Visible, NIR, SWIR, Panchromatic | 2015/2016 | Excluded |
SRTM | 30 m | Radar | 2015 | ||
Jäger and Carrion (In press) | Worldview 2 | 0.46/1.84 m | Panchromatic, Multispectral | 2015/2018 | Excluded |
Current publication | PlanetScope | 3 m | Visible, NIR | 2018 | Yes |
Sentinel-2 | 10 m | Visible, Red Edge Edge, NIR, Narrow NIR, SWIR | 2017/2019 | Yes | |
SIGTIERRAS DTM | 10 m | Visible (Stereoscopy) | 2009 | Yes |
Category | Description |
---|---|
Cedrela—Cedar | Cedrela odorata, or spanish cedar, is a semi-deciduous tree 10–30 m tall, which outcompetes most other tree species and grows into a dense canopy [46]. |
Cinchona—Quinine | The red quinine tree (Cinchona pubescens) is a 15 m broad-leaved evergreen, which was once widespread in Santa Cruz’s Miconia region (~580 masl). [47] |
Coffea—Coffee | The Coffea- and coffee category includes bushes of the arabica or robusta varieties since this is the most important cash crop and the only product that is exported. Coffee is often shade-grown with other tree crops like Citrus or banana (Musa spp.), so this category is limited to what is visible from above [40]. |
Cultivated Grass | Cultivated grass is a category that groups monocrops of less common cultivated grasses for pasture or landscaping, including grasses of Brachiara or Paspalum genera [40]. |
Erythrina— Porotillo | Erythrina smithiniana or porotillo is a shrubby tree of the Fabaceae family, which grows up to ~8 m and is commonly planted as stakes along the edges of farms to form ‘living fences’ [12]. |
Lantana–Supirosa | Lantana camara or Supirosa is an ornamental shrub up to 3 m tall that invades a wide variety of habitats, from tropical to temperate regions [48,49] |
Mixed forest | Mixed forest is a category describing a forest where there is a mixture of introduced, invasive, or native species, and the dominance of a single species cannot be established [42]. |
Permanent Crops | Permanent Crops are those that take over one year to reach productive age, and that can produce for several subsequent years without requiring replanting after each harvest. Some of the most common perennial crops include coffee (Coffea spp.), plantain, banana (Musa spp.), sugar cane (Saccharum spp.), pineapple (Ananas spp.), and orange (Citrus spp.) [40]. The permanent crops category also includes all other perennial or tree crops, such as pineapple (Ananas spp.), sugar cane (Saccharum spp.), or other tree crops, commonly of Fabaceae, Persea, or Carica genera [40]. |
Pennisetum—Elephant grass | Pennisetum purpureum or Elephant grass is the most common type of cultivated grass for cattle fodder and grows tall, robust bamboo-like clumps [40]. |
Psidium—Guava | Psidium guajava or guava is a small tree (8 m tall) that has escaped cultivation and become common in mesic forests (>150 masl) of several of the large islands [50,51]. |
Rubus—Blackberry | Rubus niveus or blackberry is a widespread thorny shrub that grows in gaps of native vegetation and forms dense thickets up to 4 m high over grasslands, bracken, bush, and forest areas alike [52]. |
Silvopasture | Silvopasture describes an intentional combination of pasture for cattle grazing and trees, which provide additional fodder for cattle, fruit crops, wood, or shade [53]. |
Syzygium—Pomarrosa | Syzygium jambos or pomarrosa is a small tree (3—15 m) that forms dense thickets and threatens several highland habitats, especially in San Cristobal and Isabela [2]. |
Transitory Crops | Transitory crops are short-cycle crops. Common ones include maize (Zea spp.), cassava (Manihot spp.), and watermelon (Citrullus spp.) [40]. |
Category | Description |
---|---|
Deciduous Forest | Deciduous forest was sometimes referred to as ‘dry or arid zone’; this area is mostly lava substrate dominated by native species like Acacia spp., Bursera graveolens, Piscidia carthagenensis, Croton scouleri, or Opuntia spp., and ranges from 0 to ~200 masl [42,46]. |
Evergreen Forest and Shrubland | The Evergreen forest and shrubland is sometimes referred to as the ‘Scalesia’, ‘brown’, and ‘Miconia’ zones. This region contains well-developed soil with vegetation characterized by an abundance of shrubs, herbs, ferns, and trees like Darwiniothamnus tenuifolius, Lycopodium spp., Scalesia pedunculata, Miconia robinsoniana, and Zantoxylum fagara. Epiphytes like mosses and liverworts commonly cover the trunks and branches of trees in this zone [42,46,51]. |
Evergreen Seasonal Forest and Shrubland | Evergreen seasonal forest and shrubland is an ecosystem previously referred to as ‘transition zone’, where soil and understory are more developed than the deciduous forest and species like Clerodendrum molle, Cordia lutea, Chiococca alba, Psidium galapageium, Tournefortia spp. can be found [42,46,51]. |
Humid Tallgrass | Humid tallgrass is a region previously known as ‘pampa zone’, which contains virtually no trees or shrubs, and its vegetation consists mainly of ferns, grasses, and sedges like Cyathea weatherbyana, Habenaria monorrhiza, or Pteridium aquilinum [42,43]. |
Pioneer | The pioneer category describes herbaceous, quick-growing native vegetation that thrives in recently disturbed areas, such as Plumbago scandens, Senna occidentalis, Mentzelia aspera, Sida rhombifolia, or Heliotropium spp., but likely also includes introduced herbaceous species like Amaranthus spp., or Pothomorphe peltata [46]. |
Sensor | Capture Date | Capture Time | Visible Islands | Cloud Cover (%) |
---|---|---|---|---|
Sentinel-2 | 21-February-17 | 11:33:01 AM EST | Isabela, Santa Cruz, Floreana | 0 |
Sentinel-2 | 10-March-19 | 12:23:11 PM EST | San Cristobal | 22 |
4-Band PlanetScope | 10-March-18 | 10:47:46 AM EST | Floreana | 0 |
4-Band PlanetScope | 10-March-18 | 10:46:47 AM EST | Floreana | 0 |
4-Band PlanetScope | 11-April-18 | 11:52:07 AM EST | Isabela | 0 |
4-Band PlanetScope | 11-April-18 | 11:52:08 AM EST | Isabela | 0 |
4-Band PlanetScope | 11-April-18 | 11:52:09 AM EST | Isabela | 0 |
4-Band PlanetScope | 9-March-18 | 10:48:35 AM EST | Santa Cruz | 1 |
4-Band PlanetScope | 9-March-18 | 10:48:36 AM EST | Santa Cruz | 1 |
4-Band PlanetScope | 9-March-18 | 10:48:37 AM EST | Santa Cruz | 0 |
4-Band PlanetScope | 10-March-18 | 10:47:34 AM EST | Santa Cruz | 0 |
4-Band PlanetScope | 10-March-18 | 10:47:35 AM EST | Santa Cruz | 0 |
4-Band PlanetScope | 10-March-18 | 10:47:36 AM EST | Santa Cruz | 0 |
4-Band PlanetScope | 10-March-18 | 10:45:18 AM EST | San Cristobal | 2 |
4-Band PlanetScope | 10-March-18 | 10:45:19 AM EST | San Cristobal | 1 |
4-Band PlanetScope | 31-March-18 | 11:44:57 AM EST | San Cristobal | 1 |
4-Band PlanetScope | 31-March-18 | 11:44:58 AM EST | San Cristobal | 7 |
Island | Number of UPAs Surveyed | UAV Survey Area (ha) | Percentage of Study Area |
---|---|---|---|
Santa Cruz | 26 | 566.89 | 1.92 |
San Cristobal | 38 | 503.37 | 2.92 |
Isabela | 12 | 124.18 | 0.98 |
Floreana | 7 | 57.85 | 3.35 |
All islands | 83 | 1252.29 | 2.05 |
PlanetScope | ||||||
---|---|---|---|---|---|---|
Bands | B1—Blue | B2—Green | B3—Red | B4—NIR | S—Syn | |
Sentinel-2 | B2—Blue | X | ||||
B3—Green | X | |||||
B4—Red | X | |||||
B5—Red Edge | X | |||||
B6—Red Edge | X | |||||
B7—Red Edge | X | |||||
B8—NIR | X | |||||
B8A—Narrow NIR | X | |||||
B11—SWIR | X | |||||
B12—SWIR | X |
Sensor | Data Layer | Mean Decrease Accuracy | Mean Decrease Gini |
---|---|---|---|
Orthophoto | Elevation | 95.59 | 94.96 |
Orthophoto | Slope | 62.39 | 63.39 |
PlanetScope | B1—Blue | 63.00 | 69.28 |
PlanetScope | B3—Red | 49.06 | 59.35 |
PlanetScope | B4—NIR | 57.42 | 69.64 |
S2 + PS | B2—Blue | 42.37 | 48.39 |
S2 + PS | B3—Green | 50.15 | 57.28 |
S2 + PS | B4—Red | 48.47 | 49.41 |
S2 + PS | B5—Red Edge | 52.94 | 44.28 |
S2 + PS | B8—NIR | 54.23 | 60.81 |
S2 + PS | B8A—Narrow NIR | 57.88 | 65.54 |
S2 + PS | B11—SWIR | 54.79 | 50.34 |
S2 + PS | B12—SWIR | 55.04 | 48.65 |
S2 + PS | NDVI | 54.59 | 62.92 |
S2 + PS | NDVRE | 55.79 | 58.22 |
S2 + PS | SI | 60.47 | 46.59 |
Land Cover Category | Orthophoto | PlanetScope | Fused Image (Sentinel-2 + PlanetScope) | |||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Elevation | Slope | B1 | B3 | B4 | B2 | B3 | B4 | B5 | B8 | B8A | B11 | B12 | NDVI | NDRE | SI | |
Bare Ground | 27.46 | 36.66 | 25.08 | 21.58 | 23.80 | 20.17 | 21.26 | 19.42 | 14.69 | 23.93 | 30.40 | 17.45 | 19.39 | 19.42 | 19.15 | 14.16 |
Built Environment | 32.04 | 23.31 | 35.90 | 27.64 | 24.26 | 25.32 | 23.94 | 24.74 | 24.45 | 22.64 | 23.27 | 24.61 | 18.71 | 21.00 | 17.35 | 28.92 |
Cedrela-Cedar | 13.26 | 4.52 | 9.92 | 10.31 | 11.21 | 12.00 | 6.56 | 13.34 | 5.08 | 10.55 | 11.23 | 9.32 | 8.27 | 28.43 | 18.14 | 7.16 |
Cinchona-Quinine | 28.42 | 14.58 | 20.86 | 12.66 | 14.24 | 17.51 | 15.95 | 10.92 | 8.34 | 12.48 | 11.95 | 7.79 | 8.78 | 13.64 | 13.11 | 10.59 |
Coffea-Coffee | 59.06 | 34.49 | 44.41 | 36.42 | 38.45 | 30.14 | 37.70 | 31.74 | 29.96 | 34.39 | 37.87 | 38.61 | 34.58 | 29.81 | 32.71 | 32.29 |
Cultivated Grass | 49.33 | 31.79 | 42.60 | 34.04 | 33.42 | 29.21 | 29.11 | 24.67 | 23.29 | 31.27 | 32.87 | 25.83 | 24.78 | 26.34 | 27.86 | 25.62 |
Deciduous Forest | 42.88 | 27.26 | 41.86 | 25.52 | 29.42 | 22.30 | 27.33 | 21.49 | 25.02 | 25.66 | 29.03 | 30.57 | 23.87 | 18.93 | 21.58 | 22.05 |
Evergreen Forest and Shrubland | 75.88 | 15.75 | 25.48 | 21.26 | 32.71 | 20.19 | 24.77 | 19.29 | 14.96 | 24.31 | 23.62 | 15.99 | 16.76 | 18.38 | 17.98 | 16.73 |
Evergreen Seasonal Forest | 40.31 | 33.18 | 39.28 | 34.25 | 32.52 | 27.11 | 30.16 | 26.59 | 24.61 | 36.30 | 34.87 | 30.92 | 30.09 | 28.36 | 31.79 | 23.99 |
Freshwater | 29.24 | 23.24 | 22.89 | 20.09 | 22.44 | 15.18 | 16.27 | 15.36 | 13.52 | 19.43 | 20.70 | 20.39 | 21.17 | 17.35 | 15.54 | 15.06 |
Humid Tallgrass | 54.93 | 42.38 | 31.21 | 26.62 | 37.64 | 24.92 | 28.50 | 25.99 | 23.24 | 30.00 | 31.36 | 23.73 | 25.83 | 24.87 | 25.85 | 21.70 |
Mixed Forest | 58.38 | 40.98 | 41.41 | 35.64 | 39.84 | 30.51 | 34.35 | 33.85 | 27.78 | 36.48 | 39.80 | 28.30 | 29.45 | 33.61 | 35.93 | 25.61 |
Pennisetum-Elephant Grass | 63.06 | 24.80 | 31.28 | 27.20 | 34.92 | 25.43 | 34.21 | 22.64 | 21.70 | 29.65 | 30.31 | 23.22 | 21.76 | 21.96 | 23.91 | 19.42 |
Permanent Crops | 50.89 | 29.67 | 33.65 | 30.74 | 31.07 | 25.96 | 34.12 | 24.27 | 23.60 | 31.56 | 33.02 | 30.08 | 27.28 | 25.95 | 26.10 | 28.21 |
Pioneer | 56.26 | 44.43 | 47.33 | 42.92 | 40.02 | 28.60 | 36.97 | 32.32 | 33.59 | 38.06 | 39.19 | 34.18 | 31.65 | 29.00 | 34.26 | 30.83 |
Psidium-Guava | 45.78 | 19.65 | 31.98 | 28.17 | 28.77 | 20.42 | 21.76 | 25.12 | 15.19 | 26.04 | 28.70 | 21.86 | 25.99 | 22.11 | 21.64 | 24.99 |
Rubus-BlackBerry | 59.99 | 24.45 | 27.46 | 25.47 | 33.71 | 19.26 | 25.26 | 23.20 | 16.56 | 23.97 | 24.54 | 15.83 | 17.76 | 24.73 | 19.63 | 14.50 |
Silvopasture | 39.14 | 20.19 | 27.40 | 23.05 | 25.29 | 25.41 | 31.43 | 23.79 | 24.40 | 25.21 | 26.80 | 28.18 | 24.70 | 20.86 | 23.25 | 20.64 |
Syzygium-Pomarosa | 17.32 | 6.83 | 15.74 | 15.93 | 23.40 | 19.39 | 23.30 | 22.63 | 12.85 | 17.79 | 19.41 | 24.70 | 19.48 | 10.55 | 14.19 | 13.89 |
Transitory Crops | 50.13 | 27.66 | 47.92 | 35.27 | 29.66 | 29.35 | 32.07 | 28.65 | 31.47 | 31.31 | 33.28 | 31.46 | 26.11 | 23.56 | 24.19 | 27.59 |
Category | Island | Common Classification Errors (>0.1) | |||
---|---|---|---|---|---|
Santa Cruz | San Cristobal | Isabela | Floreana | ||
Bare Ground | 0.04 | 0.00 | 0.02 | 0.00 | Evergreen forest: In San Cristobal, out of 50 samples, evergreen forest was misclassified as guava 5 times. Mixed forest: In San Cristobal (50 samples), mixed forest was misclassified as cedar 2 times. In Floreana, (50 samples) it was misclassified as evergreen seasonal forest 2 times. Permanent crops: In Santa Cruz (50 samples), permanent crops were misclassified as pioneer, guava, and transitory crops 2 times each. In Cristobal (50 samples) it was misclassified as transitory crops 4 times and mixed forest 3 times. In Isabela (55 Samples) it was misclassified as transitory crops 4 times. Psidium-Guava: In San Cristobal (50 Samples), guava was misclassified as evergreen forest 3 times and as mixed forest 3 times. Silvopasture: In Santa Cruz, silvopasture (50 samples) was misclassified as permanent crops 4 times, as pioneer 3 times, and as guava, cultivated grass, and humid tallgrass 2 times each. Transitory crops: In Isabela (55 Samples), transitory crops were misclassified as permanent crops 7 times. |
Built Environment | 0.02 | 0.02 | 0.00 | 0.00 | |
Cedrela-Cedar | 0.02 | 0.02 | 0.00 | 0.06 | |
Cinchona-Quinine | 0.00 | NA | NA | NA | |
Coffea-Coffee | 0.04 | 0.00 | 0.00 | NA | |
Cultivated Grass | 0.02 | 0.10 | 0.07 | 0.00 | |
Deciduous Forest | 0.06 | 0.02 | 0.02 | 0.00 | |
Evergreen Forest and Shrubland | 0.02 | 0.18 | 0.00 | 0.06 | |
Evergreen Seasonal Forest | 0.10 | 0.08 | 0.00 | 0.06 | |
Freshwater | 0.00 | 0.00 | 0.00 | 0.00 | |
Humid Tallgrass | 0.02 | 0.00 | 0.02 | NA | |
Mixed Forest | 0.02 | 0.12 | 0.07 | 0.12 | |
Pennisetum-Elephant Grass | 0.08 | 0.00 | 0.00 | NA | |
Permanent Crops | 0.28 | 0.20 | 0.18 | 0.00 | |
Pioneer | 0.08 | 0.02 | 0.00 | 0.00 | |
Psidium-Guava | 0.04 | 0.16 | 0.09 | 0.08 | |
Rubus-BlackBerry | 0.00 | 0.00 | 0.00 | 0.00 | |
Silvopasture | 0.38 | 0.02 | 0.07 | 0.02 | |
Syzygium-Pomarrosa | NA | 0.02 | 0.00 | NA | |
Transitory Crops | 0.02 | 0.06 | 0.24 | 0.04 | |
OOB Estimate of Error Rate | 6.20% | 5.14% | 4.11% | 2.76% |
All Islands | ||||||
---|---|---|---|---|---|---|
Land Cover | Agricultural Area | Buffer Zone | Total | |||
Ha | % | Ha | % | Ha | % | |
Bare Ground | 18.63 | 0.07 | 513.04 | 1.45 | 531.67 | 0.88 |
Built Environment | 259.04 | 1.03 | 35.81 | 0.10 | 294.85 | 0.49 |
Cedrela-Cedar | 1349.62 | 5.34 | 2574.54 | 7.29 | 3924.16 | 6.48 |
Cinchona-Quinine | 17.42 | 0.07 | 48.25 | 0.14 | 65.67 | 0.11 |
Coffea-Coffee | 944.86 | 3.74 | 41.95 | 0.12 | 986.81 | 1.63 |
Cultivated Grass | 2402.48 | 9.51 | 119.05 | 0.34 | 2521.53 | 4.16 |
Deciduous Forest | 268.96 | 1.06 | 8542.59 | 24.20 | 8811.55 | 14.55 |
Evergreen Forest and Shrubland | 2428.89 | 9.62 | 2737.84 | 7.76 | 5166.73 | 8.53 |
Evergreen Seasonal Forest | 1642.12 | 6.50 | 13,379.97 | 37.91 | 15,022.09 | 24.81 |
Freshwater | 29.39 | 0.12 | 7.64 | 0.02 | 37.03 | 0.06 |
Humid Tallgrass | 369.84 | 1.46 | 987.56 | 2.80 | 1357.40 | 2.24 |
Mixed Forest | 1877.17 | 7.43 | 2830.53 | 8.02 | 4707.70 | 7.77 |
Pennisetum-Elephant Grass | 103.85 | 0.41 | 531.54 | 1.51 | 635.39 | 1.05 |
Permanent Crops | 2969.38 | 11.75 | 232.10 | 0.66 | 3201.48 | 5.29 |
Pioneer | 1048.90 | 4.15 | 70.01 | 0.20 | 1118.91 | 1.85 |
Psidium-Guava | 4958.86 | 19.63 | 2420.95 | 6.86 | 7379.81 | 12.19 |
Rubus-BlackBerry | 325.39 | 1.29 | 81.42 | 0.23 | 406.81 | 0.67 |
Silvopasture | 3113.75 | 12.33 | 82.87 | 0.23 | 3196.62 | 5.28 |
Syzygium-Pomarosa | 434.04 | 1.72 | 29.08 | 0.08 | 463.12 | 0.76 |
Transitory Crops | 698.43 | 2.76 | 28.34 | 0.08 | 726.77 | 1.20 |
Total | 25,261.00 | 100.00 | 35,295.10 | 100.00 | 60,556.10 | 100.00 |
Island | Land Cover | Agricultural Area | Buffer Zone | Total | |||
---|---|---|---|---|---|---|---|
Ha | % | Ha | % | Ha | % | ||
Santa Cruz | Native Vegetation | 1500.40 | 13.12 | 14,065.95 | 76.92 | 15,566.35 | 52.37 |
Invasive Vegetation | 2474.12 | 21.63 | 3061.52 | 16.74 | 5535.64 | 18.62 | |
Pastures | 3726.33 | 32.58 | 185.67 | 1.02 | 3911.99 | 13.16 | |
Transitory and Permanent Crops | 2549.13 | 22.29 | 118.93 | 0.65 | 2668.07 | 8.98 | |
Mixed Forest and Pioneer | 1090.52 | 9.53 | 948.41 | 5.19 | 2038.93 | 6.86 | |
San Cristobal | Native Vegetation | 2535.61 | 30.40 | 6981.65 | 87.10 | 9517.25 | 58.18 |
Invasive Vegetation | 2766.56 | 33.17 | 270.02 | 3.37 | 3036.58 | 18.56 | |
Pastures | 790.09 | 9.47 | 67.67 | 0.84 | 857.76 | 5.24 | |
Transitory and Permanent Crops | 972.11 | 11.65 | 81.63 | 1.02 | 1053.73 | 6.44 | |
Mixed Forest and Pioneer | 1175.85 | 14.10 | 468.43 | 5.84 | 1644.28 | 10.05 | |
Isabela | Native Vegetation | 657.99 | 12.63 | 3555.66 | 47.22 | 4213.66 | 33.08 |
Invasive Vegetation | 1871.86 | 35.93 | 2149.56 | 28.55 | 4021.42 | 31.57 | |
Pastures | 1047.19 | 20.10 | 467.18 | 6.20 | 1514.37 | 11.89 | |
Transitory and Permanent Crops | 1017.21 | 19.52 | 92.31 | 1.23 | 1109.52 | 8.71 | |
Mixed Forest and Pioneer | 620.51 | 11.91 | 1302.27 | 17.30 | 1922.78 | 15.09 | |
Floreana | Native Vegetation | 15.81 | 5.84 | 1044.70 | 71.43 | 1060.52 | 61.17 |
Invasive Vegetation | 76.63 | 28.28 | 204.68 | 13.99 | 281.32 | 16.23 | |
Pastures | 56.48 | 20.84 | 12.95 | 0.89 | 69.42 | 4.00 | |
Transitory and Permanent Crops | 74.22 | 27.38 | 9.52 | 0.65 | 83.73 | 4.83 | |
Mixed Forest and Pioneer | 39.18 | 14.46 | 181.43 | 12.40 | 220.62 | 12.73 | |
All Islands | Native Vegetation | 4709.81 | 18.64 | 25,647.96 | 72.67 | 30,357.77 | 50.13 |
Invasive Vegetation | 7189.17 | 28.46 | 5685.79 | 16.11 | 12,874.96 | 21.26 | |
Pastures | 5620.08 | 22.25 | 733.46 | 2.08 | 6353.54 | 10.49 | |
Transitory and Permanent Crops | 4612.67 | 18.26 | 302.39 | 0.86 | 4915.06 | 8.12 | |
Mixed Forest and Pioneer | 2926.06 | 11.58 | 2900.54 | 8.22 | 5826.60 | 9.62 |
Island | R2 | RMSE (%) |
---|---|---|
Santa Cruz | 0.83 | 16.99 |
San Cristobal | 0.70 | 19.52 |
Isabela | 0.66 | 22.34 |
Floreana | 0.58 | 23.85 |
Average | 0.69 | 20.68 |
Cover | R2 | RMSE (%) |
---|---|---|
Cedrela—Cedar | 0.91 | 14.53 |
Built Environment | 0.57 | 2.73 |
Coffea—Coffee | 0.19 | 8.84 |
Cultivated Grass | 0.41 | 32.81 |
Evergreen Forest and Shrubland | 0.94 | 15.01 |
Pennisetum—Elephant Grass | 1.00 | 31.47 |
Mixed Forest | 0.69 | 22.44 |
Permanent Crops | 0.56 | 22.61 |
Pioneer | 0.03 | 27.59 |
Psidium—Guava | 0.68 | 23.84 |
Rubu—Blackberry | 0.13 | 13.16 |
Silvopasture | 0.63 | 25.90 |
Transitory Crops | 0.26 | 17.80 |
Syzygium—Pomarrosa | 1.00 | 7.47 |
2014 Agricultural Census | This Study | ||||
---|---|---|---|---|---|
Land Cover / Use | ha | % | ha | % | Categories Included |
Permanent crops | 1517 | 8 | 3913 | 15 | Permanent Crops, Coffea |
Transitory crops | 220 | 1 | 698 | 3 | Transitory crops |
Tilled land | 110 | 1 | NA | NA | |
Fallow land | 433 | 2 | NA | NA | |
Pastures | 11,126 | 59 | 5618 | 22 | Cultivated Grass, Pennisetum, Silvopasture |
Invasive species | 934 | 5 | 7080 | 28 | Psidium, Rubus, Cinchona, Syzygium, Cedrela |
Pioneer and forest | 4189 | 22 | 7630 | 30 | Pioneer, Mixed Forest, Native vegetation |
Other Uses | 482 | 3 | 307 | 1 | Built Environment, bare ground, water |
Total | 19,010 | 100 | 25,246 | 100 |
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Share and Cite
Laso, F.J.; Benítez, F.L.; Rivas-Torres, G.; Sampedro, C.; Arce-Nazario, J. Land Cover Classification of Complex Agroecosystems in the Non-Protected Highlands of the Galapagos Islands. Remote Sens. 2020, 12, 65. https://doi.org/10.3390/rs12010065
Laso FJ, Benítez FL, Rivas-Torres G, Sampedro C, Arce-Nazario J. Land Cover Classification of Complex Agroecosystems in the Non-Protected Highlands of the Galapagos Islands. Remote Sensing. 2020; 12(1):65. https://doi.org/10.3390/rs12010065
Chicago/Turabian StyleLaso, Francisco J., Fátima L. Benítez, Gonzalo Rivas-Torres, Carolina Sampedro, and Javier Arce-Nazario. 2020. "Land Cover Classification of Complex Agroecosystems in the Non-Protected Highlands of the Galapagos Islands" Remote Sensing 12, no. 1: 65. https://doi.org/10.3390/rs12010065