Los Angeles County is a biodiversity hotspot that harbors over 4,000 species of plants and animals. The most populous county in the nation, L.A. County offers a unique environment where more than 10 million people coexist with wildlife. The biodiversity of L.A. County provides many benefits to people, including air and water purification, food security and mental/physical well-being. But land development and climate change threaten the county’s species, their habitats, and the region's ecosystem. With 1 million animal and plant species globally facing extinction due to human activity, efforts to better understand the factors that shape biodiversity in Los Angeles could help shape global conservation efforts. 

Reducing water consumption in Los Angeles County so that the region can achieve 100% local water, as well as enhancing ecosystem health, are two key targets of the Sustainable LA Grand Challenge. However, an apparent contradiction exists between increasing urban vegetation and reducing water use in the Los Angeles Basin. Therefore, the interconnections between the L.A. region’s water use and urban ecosystems need to be better understood. In this project, researchers reconstruct historical urban ecosystem changes in the region over the past several decades to inform future landscape and water management practices. 

Southern California experienced a significant drought from 2012 to 2016, which was exacerbated by warming due to climate change. Defined by unprecedented high temperatures and low annual precipitation, it was the driest four-year span in the last 1,200 years.  As a result, overall vegetation health and cover has most likely been affected (e.g. decline in greenness, high vegetation mortality in chaparral-dominated communities). Changes in vegetation health and cover create favorable conditions for wildfires and landslides. These changes threaten both the stability of the natural environment and the structures that depend on it, such as built electricity generation plants, power lines and pipelines. Because these types of infrastructure are often located on or run through wildland areas, changes in vegetation, wildfires and landslides can impact the region’s energy supplies. To better understand these impacts and assess Los Angeles County’s energy supply vulnerabilities, researchers analyzed the impacts of the 2012-2016 drought on vegetation health and cover using satellite and geospatial environmental data. 

Los Angeles County is the largest county in the nation with a population of approximately 10 million people. By 2050, the county is projected to have a 15% increase in population, adding 1.5 million more residents. With projected urban population growth alongside the effects of climate change, providing Angelenos with reliable energy, water and an environment that will enhance their health will be a challenge. The UCLA Sustainable LA Grand Challenge (SLA GC) was developed to address these problems and ultimately transition Los Angeles County to 100% renewable energy, 100% locally sourced water, and enhanced ecosystem and human health by 2050. In response to SLA GC’s original goals, The NOW Institute research team undertook a first-round assessment of where the county stands today and what can be done to achieve those targets by 2050.

The Los Angeles region lies within one of only 36 biodiversity hotspots in the world with more than 4,000 unique native plant and animal species recorded by community science efforts to date. However, development, direct exploitation, climate change, pollution and invasive species threaten our native biodiversity. To better manage our native biodiversity and ensure future generations benefit from the ecosystem services such as food production, environmental health and wellbeing, we need to better understand the breadth of the diversity that exists in our region. Realizing that species conservation efforts must incorporate both evolutionary and genetic data, the UCLA research team will apply genomic tools to assess the genetic diversity of species across the Los Angeles Basin and provide recommendations for effective management strategies to preserve and enhance these critical natural resources.

Los Angeles County is known for its rich wildlife biodiversity in our natural areas such as the Santa Monica and San Gabriel mountains. Mammalian biodiversity has been declining for decades in the Los Angeles urban area due to human activity. As an important indicator of ecosystem health, mammals play essential roles in the food webs of every ecosystem. Since they feed at various levels of food chains, mammals help regulate populations of diverse plant and animal species and also take part in seed dispersal and plant pollination.  Such a decline in population sizes and dynamics of mammals is also relevant since it can potentially alter pathogen load and diversity, which in turn poses health risks to humans, pets and other wildlife species.  To this day, the abundance of biodiversity and the population dynamics of mammals within the built urban environment of Los Angeles are both not well known. Additionally, public perceptions and their interactions with urban mammals such as raccoons, rats and opossums have not been previously characterized in the area. To address this knowledge gap, UCLA researchers take on a cross-scale research project to elucidate the biodiversity—urban ecology of mammals, their pathogen carriage and public perceptions of mammalian wildlife—within the urban Los Angeles County ecosystem. 

Raptors (e.g. hawks, owls, falcons) are large, charismatic bird species at the top of the food chain. They experienced human-driven population crashes during the 19th and 20th centuries. While a subset of these species has recovered in the Los Angeles region, others have not — and are intolerant of urbanization and other human activities. To help these species survive, it is critical to identify various factors, such as how well they can tolerate urbanization, as well as their historical and current habitats and nesting areas for future conservation practices. Nesting areas of raptors are also important indicators of ecosystem health in urban areas like the Los Angeles region.   Several government agencies, developers and nonprofit organizations collect data on urban-nesting raptors around the Los Angeles Basin, but these efforts are not well-coordinated. If this information can be consolidated, it will be useful to creating management tools like maps and databases that can help guide local policy and land-use decisions. 

Physical activity (PA) improves the quality of life and health and is closely linked to the built environment. To promote sustainable and active living in communities, many cities are implementing bike sharing programs. These programs provide co-benefits of reduced emissions by decreasing vehicle miles traveled (VMT). However, no study has been conducted locally to quantify and assess the impacts on PA patterns and health. PASTA-LA, a sister-study of the European Union PASTA project, will be the first and only study outside of Europe to explore the health-related outcomes of bike share in Los Angeles, California. 

Los Angeles County has high rates of food insecurity, federal food assistance and chronic diet-related diseases, in part due to lack of access to fresh fruits and vegetables and limited green space and safe outdoor spaces in many communities. Urban agriculture has the potential to improve public health through increased food access and consumption, thus may help address urban food insecurity. However, there is very limited data and documentation of urban agriculture activities (e.g. size, production, crop types) in the County. Recognizing this data gap, this project expanded the current documentation efforts and assessed the production potential focusing on how urban agriculture affects public health by integrating health impact assessment (HIA) methodology, geospatial analysis and policy review. 

Transportation emissions are a primary cause of Los Angeles’ notoriously poor air quality. Policymakers and “smart growth” advocates assert that intensifying land use around the public transit rail system will not only help accomplish transportation and environmental goals, but also housing and economic development goals. However, recent studies reveal that rail development is linked to gentrification and displacement of public transit’s core ridership. This project combined literature and policy review, spatial analysis and interviews to investigate underlying causes and develop future policy recommendations that prioritize social equity and minimize displacement.