![]() Most previous studies either exclude the agricultural areas or suffer from high cloud cover concentrations over the humid highlands ( Table 1). Past and Present Efforts to Map the Humid Highlands and Agroecosystems of the Galapagos Using Remote Sensing Taking advantage of newly-available high-resolution sensors, commonly-used vegetation indices, object-based approaches, and contemporary machine learning methods, we can create an easily-replicable methodology that addresses the challenges of creating high-quality classification maps of regions like the humid highlands of the Galapagos. Object-based classification of high-resolution images using machine learning algorithms, like random forest, is an efficient method for classifying smallholder agricultural systems and mapping invasive species with high accuracy results. Machine learning methods, like decision trees, have become common and have been shown to have higher accuracy than parametric classification methods like maximum likelihood classifiers as they do not require assuming a particular statistical model for the distribution of the training data. Object-based classification methods have been found to handle nuanced classification of high-resolution images better than pixel-based classification methods. The inclusion of vegetation indices is useful for differentiating land cover types that have variable spectral responses based on local conditions, such as moisture and vegetation health. Among the plethora of methods, sensors, vegetation indices, and classification algorithms used for mapping island ecosystems and agricultural landscapes, methods that combine multiple data sources of complementary resolutions have been among the most successful at accurately classifying land cover. ![]() The persistent cloud coverage, high biological diversity, and high landscape heterogeneity of island agroecosystems like those in the Galapagos make them challenging regions to classify. Given the direct influence of agriculture on both the introduction and control of introduced species, local governance seeks to incentivize agroecological models that serve to control the spread of invasive plants to nearby native dominated patches or to the protected lowlands while simultaneously contributing to local food security. Crop production and cattle ranching, when properly implemented, can effectively be used to control the spread of invasive plants or even rehabilitate invaded lands. Presently, the humid highlands of the Galapagos record higher numbers of invasive plants when compared to the dry lowlands, and these plants not only threaten agricultural systems but also the remaining patches of native-dominated ecosystems that still exist in the non-protected areas of this Ecuadorian archipelago. Vast expanses of agricultural land in the Galapagos have become abandoned in the last decades, making this UNESCO Natural World Heritage Site vulnerable to invasive plants, which thrive in disturbed environments. The produced dataset is designed to suit the needs of practitioners of both conservation and agriculture and aims to foster collaboration between the two areas. Our results are consistent with historical trajectories of colonization and abandonment of the highlands. ![]() Despite the astounding diversity and heterogeneity of the highland landscape, our classification yielded useful results (overall Kappa: 0.7, R 2: 0.69) and revealed that across all four inhabited islands, invasive plants cover the largest fraction (28.5%) of the agricultural area, followed by pastures (22.3%), native vegetation (18.6%), food crops (18.3%), and mixed forest and pioneer plants (11.6%). We used images collected with an unmanned aerial vehicle (UAV) to verify and validate our classified map. ![]() We combined the high spatial resolution of PlanetScope images with the high spectral resolution of Sentinel-2 images in an object-based classification using a RandomForest algorithm. We generated a baseline high-resolution land cover map of the agricultural zones and their surrounding protected areas. These areas are crucial for the region’s food security and for the control of invasive plants, but little is known about the spatial distribution of its land cover. The humid highlands of the Galapagos are the islands’ most biologically productive regions and a key habitat for endemic animal and plant species.
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