Knowledge to Serve the City: Insights from an Emerging Knowledge-Action Network to Address Vulnerability and Sustainability in San Juan, Puerto Rico

This paper presents initial efforts to establish the San Juan Urban Long-Term Research Area Exploratory (ULTRA-Ex), a long-term program aimed at developing transdisciplinary social-ecological system (SES) research to address vulnerability and sustainability for the municipality of San Juan. Transdisciplinary approaches involve the collaborations between researchers, stakeholders, and citizens to produce socially-relevant knowledge and support decision-making. We characterize the transdisciplinary arrangement emerging in San Juan ULTRA-Ex as a knowledge-action network composed of multiple formal and informal actors (e.g., scientists, policymakers, civic organizations and other stakeholders) where knowledge, ideas, and strategies for sustainability are being produced, evaluated, and validated. We describe in this paper the on-the-ground social practices and dynamics that emerged from developing a knowledge-action network in our local context. Specifically, we present six social practices that were crucial to the development of our knowledge-action network: 1) understanding local framings; 2) analyzing existing knowledge-action systems in the city; 3) framing the social-ecological research agenda; 4) collaborative knowledge production and integration; 5) boundary objects and practices; and 6) synthesis, application, and adaptation. We discuss key challenges and ways to move forward in building knowledge-action networks for sustainability. Our hope is that the insights learned from this process will stimulate broader discussions on how to develop knowledge for urban sustainability, especially in tropical cities where these issues are under-explored

Synthesis of Household Yard Area Dynamics in the City of San Juan Using Multi-Scalar Social-Ecological Perspectives

Urban sustainability discourse promotes the increased use of green infrastructure (GI) because of its contribution of important ecosystem services to city dwellers. Under this vision, all urban green spaces, including those at the household scale, are valued for their potential contributions to a city’s social-ecological functioning and associated benefits for human well-being. Understanding how urban residential green spaces have evolved can help improve sustainable urban planning and design, but it requires examining urban processes occurring at multiple scales. The interaction between social structures and ecological structures within the subtropical city of San Juan, the capital and the largest city of Puerto Rico, has been an important focus of study of the San Juan ULTRA (Urban Long-Term Research Area) network, advancing understanding of the city’s vulnerabilities and potential adaptive capacity. Here we provide a synthesis of several social-ecological processes driving residential yard dynamics in the city of San Juan, Puerto Rico, through the evaluation of empirical findings related to yard management decisions, yard area, and yard services. We emphasize the role of factors occurring at the household scale. Results are discussed within the context of shrinking cities using an integrated, multi-scalar, social-ecological systems framework, and consider the implications of household green infrastructure for advancing urban sustainability theory

Spatial patterns of distribution and abundance of Harrisia portoricensis, an endangered Caribbean cactus

Abstract Aims The spatial distribution of biotic and abiotic factors may play a dominant role in determining the distribution and abundance of plants in arid and semiarid environments. In this study, we evaluated how spatial patterns of microhabitat variables and the degree of spatial dependence of these variables influence the distribution and abundance of the endangered cactus Harrisia portoricensis. Methods We used geostatistical analyses of five microhabitat variables (e.g. vegetation cover, soil cover and light incidence) and recorded the abundance of H. portoricensis in 50 permanent plots established across Mona Island, Puerto Rico, by the United States Department of Agriculture Forest Service as part of the Forest Inventory and Analysis (USDA-FIA). We also used partial Mantel tests to evaluate the relationships between microhabitat variables and abundance of H. portoricensis, controlling for spatial autocorrelation. Important findings Abundance of H. portoricensis showed strong affinities with microhabitat variables related to canopy structure, soil cover and light environment. The distribution of this cactus species throughout the island was consistent with the spatial variation patterns of these variables. In general, landscape-level analyses suggested a predictive value of microhabitat traits for the distribution and abundance of this endangered species. For sensitive cacti species, wherein abundance may be influenced by similar variables, these types of analyses may be helpful in developing management plans and identifying critical habitats for conservation

Do epiphytic orchids behave as metapopulations? Evidence from colonization, extinction rates and asynchronous population dynamics

Previous in situ studies of orchid population dynamics with conservation relevance have focused on one or a few populations in a limited area. Many species of orchids occur as hyperdispersed populations in ephemeral habitats (epiphytic, twig epiphytes, short lived or vulnerable host). In this contribution, we show that orchid populations that are patchily distributed and that exist in disturbance-prone environments may act somewhat like a metapopulation with high turnover and low correlation in population dynamics. We tested for evidence of metapopulation dynamics in the riparian orchid Lepanthes rupestris by sampling over 1000 sites (250 initially occupied, 750 initially unoccupied) in biannual surveys for 5 years. Extinction and colonization of groups of orchids on a single substrate or patch (either trees or boulders) was common and more or less consistent across different time periods, and asynchronous subpopulation dynamics were evident among the populations. From this we predict non-zero equilibrium values for site occupancy (P ) of L. rupestris. Nevertheless, this study species differed from a typical Levins' metapopulation system in that small populations were more likely to go extinct than large populations, and that colonization of previously occupied sites was more common than colonization of initially unoccupied sites suggesting that site quality may influence population persistence and colonization. A major difficulty applying the metapopulation approach to orchid conservation is identifying empty sites suitable for colonization. In spite of this limitation, our study highlights the necessity of following multiple orchid subpopulations (e.g., an entire orchid ''metapopulation'' in the broad sense) may provide a more accurate basis for predicting persistence in epiphytic orchids

Data from: Variation across river channels in demographic dynamics of a riparian herb with threatened status: management and conservation implications

PREMISE OF THE STUDY: Gesneria pauciflora is a rare-threatened plant growing in riparian forests. Periodic disturbances, expected in this habitat, could influence demographic dynamics on plant populations, yet their impact may not be the same across watershed. We hypothesize that differences in disturbances between the main-channel and tributaries may lead to spatial dissimilarities in population growth rate (λ), structure, and fecundity. METHODS: 1277 plants were tagged and monitored over a 1.5-years period. Every 6-months we measured plant size, survival and fecundity, in addition to appearance of seedlings. These variables were applied in Integral Projection Models to assess the population status of G. pauciflora. KEY RESULTS: Plants in the main-channel were smaller but were more likely to flower and fruit than those in the tributaries. Overall mortality was greater in the main-channel and more so during the rainy season. At both sites λ ranged from 0.9114-0.9865, and survival/growth of larger plants had a greater effect on lambda (> 0.90) regardless of site. CONCLUSIONS: Lambda values suggest that G. pauciflora is declining across the watershed. Higher mortality rates in the main channel (more-perturbed sites) might driving G. pauciflora to reproduced at smaller sizes, while the tributaries (less-perturbed sites) may benefit growth and lead to larger plant sizes. Extreme climatic events are expected to increase in the Caribbean and might decrease the population if left unmanaged. Management strategies that reduce the time plants require to reach larger sizes might be necessary to increase λ, and reintroduction of cuttings might be a possible solution

Characterization of Dry-Season Phenology in Tropical Forests by Reconstructing Cloud-Free Landsat Time Series

Fine-resolution satellite imagery is needed for characterizing dry-season phenology in tropical forests since many tropical forests are very spatially heterogeneous due to their diverse species and environmental background. However, fine-resolution satellite imagery, such as Landsat, has a 16-day revisit cycle that makes it hard to obtain a high-quality vegetation index time series due to persistent clouds in tropical regions. To solve this challenge, this study explored the feasibility of employing a series of advanced technologies for reconstructing a high-quality Landsat time series from 2005 to 2009 for detecting dry-season phenology in tropical forests; Puerto Rico was selected as a testbed. We combined bidirectional reflectance distribution function (BRDF) correction, cloud and shadow screening, and contaminated pixel interpolation to process the raw Landsat time series and developed a thresholding method to extract 15 phenology metrics. The cloud-masked and gap-filled reconstructed images were tested with simulated clouds. In addition, the derived phenology metrics for grassland and forest in the tropical dry forest zone of Puerto Rico were evaluated with ground observations from PhenoCam data and field plots. Results show that clouds and cloud shadows are more accurately detected than the Landsat cloud quality assessment (QA) band, and that data gaps resulting from those clouds and shadows can be accurately reconstructed (R2 = 0.89). In the tropical dry forest zone, the detected phenology dates (such as greenup, browndown, and dry-season length) generally agree with the PhenoCam observations (R2 = 0.69), and Landsat-based phenology is better than MODIS-based phenology for modeling aboveground biomass and leaf area index collected in field plots (plot size is roughly equivalent to a 3 × 3 Landsat pixels). This study suggests that the Landsat time series can be used to characterize the dry-season phenology of tropical forests after careful processing, which will help to improve our understanding of vegetation–climate interactions at fine scales in tropical forests

Characterization of Dry-Season Phenology in Tropical Forests by Reconstructing Cloud-Free Landsat Time Series

Fine-resolution satellite imagery is needed for characterizing dry-season phenology in tropical forests since many tropical forests are very spatially heterogeneous due to their diverse species and environmental background. However, fine-resolution satellite imagery, such as Landsat, has a 16-day revisit cycle that makes it hard to obtain a high-quality vegetation index time series due to persistent clouds in tropical regions. To solve this challenge, this study explored the feasibility of employing a series of advanced technologies for reconstructing a high-quality Landsat time series from 2005 to 2009 for detecting dry-season phenology in tropical forests; Puerto Rico was selected as a testbed. We combined bidirectional reflectance distribution function (BRDF) correction, cloud and shadow screening, and contaminated pixel interpolation to process the raw Landsat time series and developed a thresholding method to extract 15 phenology metrics. The cloud-masked and gap-filled reconstructed images were tested with simulated clouds. In addition, the derived phenology metrics for grassland and forest in the tropical dry forest zone of Puerto Rico were evaluated with ground observations from PhenoCam data and field plots. Results show that clouds and cloud shadows are more accurately detected than the Landsat cloud quality assessment (QA) band, and that data gaps resulting from those clouds and shadows can be accurately reconstructed (R2 = 0.89). In the tropical dry forest zone, the detected phenology dates (such as greenup, browndown, and dry-season length) generally agree with the PhenoCam observations (R2 = 0.69), and Landsat-based phenology is better than MODIS-based phenology for modeling aboveground biomass and leaf area index collected in field plots (plot size is roughly equivalent to a 3 × 3 Landsat pixels). This study suggests that the Landsat time series can be used to characterize the dry-season phenology of tropical forests after careful processing, which will help to improve our understanding of vegetation–climate interactions at fine scales in tropical forests

Synthesis of Household Yard Area Dynamics in the City of San Juan Using Multi-Scalar Social-Ecological Perspectives

Urban sustainability discourse promotes the increased use of green infrastructure (GI) because of its contribution of important ecosystem services to city dwellers. Under this vision, all urban green spaces, including those at the household scale, are valued for their potential contributions to a city’s social-ecological functioning and associated benefits for human well-being. Understanding how urban residential green spaces have evolved can help improve sustainable urban planning and design, but it requires examining urban processes occurring at multiple scales. The interaction between social structures and ecological structures within the subtropical city of San Juan, the capital and the largest city of Puerto Rico, has been an important focus of study of the San Juan ULTRA (Urban Long-Term Research Area) network, advancing understanding of the city’s vulnerabilities and potential adaptive capacity. Here we provide a synthesis of several social-ecological processes driving residential yard dynamics in the city of San Juan, Puerto Rico, through the evaluation of empirical findings related to yard management decisions, yard area, and yard services. We emphasize the role of factors occurring at the household scale. Results are discussed within the context of shrinking cities using an integrated, multi-scalar, social-ecological systems framework, and consider the implications of household green infrastructure for advancing urban sustainability theory