Our group is interested in a broad array of ecological applications using remote sensing, geographic information systems (GIS) and spatial analysis, including (but not limited to) ecological co-benefits and landscape dynamics of wetland regions; social and ecological implications of urban thermal patterns; landscape heterogeneity as a driver of biodiversity and ecosystem services. Here are the examples of our major current projects:
Urban thermal-vegetation patterns and socioeconomic context of development
Urban development profoundly impacts vegetation and its ecological services via changes in composition and landscape configuration of plant cover, reduction and fragmentation of pre-development ecosystems, or, conversely, introduction of novel non-native green elements. These alterations affect the thermal signatures and heat hazards associated with development, while their spatial footprints may vary with a number of social, economic and ecological factors in a given region. We are using different types of satellite remote sensing data to better understand these effects and develop cost-effective indicators of urban change and well-being for data-limited regions, particularly those experiencing rapid urban sprawl.
Remote sensing of wetland ecosystem services and dynamics
Both in California and globally, emergent wetland plants control important ecosystem processes related to productivity, carbon and nutrient cycling and soil formation, as well as wildlife habitats and various recreational, aesthetic and cultural values to humans. Changing climate, increasing demands for water, alien species invasions and other pressures create urgent needs to better understand multi-functionality of wetland canopies and their response to change drivers in order to develop sustainable management and planning strategies for the multi-functional Delta landscape. We are taking advantage of the rich remote sensing and geospatial data libraries and diversity of wetland field sites in the region to study landscape-scale variation in biophysical characteristics of wetland canopies such as leaf area index and implications of this change for regional wetland ecosystem function and services, response to disturbance and connections with land use history.
Remote sensing tools for wetland restoration monitoring
Massive wetland restoration efforts are unfolding globally in response to threats from biodiversity losses and sea level rise and opportunities presented by wetland capacity to sequester greenhouse gases, particularly atmospheric CO2. However, restored wetlands may not always behave like their natural prototypes, and understanding their ecological benefits and trajectories requires comprehensive monitoring. Such monitoring is challenging to perform in the field alone due to limited mobility, on-the-ground hazards and risks of disturbing sensitive species. Very high resolution remote sensing offers a unique potential to assess post-restoration dynamics at the whole-site scales and to complement the information from the ground surveys. We are testing this potential and exploring the informative indicators of wetland change focusing on restored marshes in the California Delta to facilitate monitoring, management and related research efforts, such as monitoring of greenhouse gas fluxes by the UC Berkeley’s Biometeorology Lab.
Bridging landscape ecological functionality with aesthetic and cultural qualities relevant to human perception and design priorities
Another aspect of our research explores the intersections between environmental heterogeneity, which underlies a number of important ecosystem services (or human-centric benefits) and indicators of visual complexity relevant to subjective preferences and objective criteria for landscape aesthetic quality and scenic beauty. Although definitions of heterogeneity and complexity differ between ecological and aesthetic interpretations of this concept, they often indicate similar landscape properties and ecological values. A recent review by Iryna suggests that such an overlap offers a potential towards a cross-disciplinary bridge and joint use of visual and ecological complexity to promote resilient and multi-functional landscapes. These issues are also relevant to efforts on combining human land use priorities with biodiversity facilitation and conservation in working landscapes.
High-resolution approaches to detect “mesoscale” distributions of invasive plant species
The applications of remote sensing to detect and monitor invasive species have been expanding in various regions; however, they are frequently challenged by scattered, non-uniform distributions and small patch size of invaders at early infestation stages. Yet, these early stages are especially important for rapid detection, effective management and overall better understanding of the ecology of these species and their spread. Novel opportunities with very high resolution (<0.5m) imaging from aerial platforms are promising to enhance such detection not only by detecting smaller patches more accurately, but also by distinguishing their unique spatial patterns. We are currently investigating such opportunities in selected wetland and grassland sites in California. Once accurate distributions of invaders can be obtained for a given site, they can be further applied to studies of infestation progress and ecological factors that facilitate or inhibit spread.