Identifying process scales in the Indian river lagoon, Florida using wavelet transform analysis of dissolved oxygen

The Indian River Lagoon (IRL) estuary in Florida is experiencing emergent “super” algal blooms in the northern reaches, a complex process occurring within a highly interconnected and complex system. This study describes the spatio-temporal structure of dissolved oxygen observations within the estuary to assist in identification of causes for these emergent conditions. Exploratory data analysis describes the data. Wavelet transform computations describe patterns of stable processes and discontinuities in the expected seasonality of the observations. Dissimilarity analysis describes spatial clusters based on these temporal characteristics. These clusters allow for comparison of the results at multiple spatial scales related to external socio-economic processes. Combined, the results provide multiple, highly localized scale domains and thresholds. This space-time localization allows for synthesis with unexamined variables of similar or different data types to assist in identification of functional relationships or causal mechanisms. The expected spatial relatedness between sampled locations is not present, indicating difficulties for management of the estuary. Our conclusions suggest a shift in focus from restoration of historic waterscapes to restoration of the expected seasonality of dissolved oxygen.