The LRWP is often asked to identify top environmental issues facing our Central New Jersey watershed communities, and every year we develop a “Top 10” list of concerns. Through 2019 we feature these concerns in blog posts that explore the issues (and potential solutions) in more detail. In September we consider how loss of biodiversity reduces the ability of our local urban ecosystems to cope with threats from pollution, climate change and other human activities. Taking steps to increase local biodiversity should be on the agenda of every urban municipality in the state.
For humans, the mental and physical health and well-being, air purifying, water filtering, and other benefits of nature matter most in the places they live. Densely populated regions in New Jersey, like the Lower Raritan Watershed, are home to the majority of the state’s residents. Concentrating populations in cities, where ecological footprints per capita are lower, spares land from development and is favorable for overall global biodiversity. Biodiversity is not just an issue for rural land managers. Biodiversity matters for our cities, too. Increasing biodiversity should be on the agenda of every urban municipality in the state.
The first “Intergovernmental Assessment of Biodiversity Summary for Policymakers”, released in May 2019, paints a grim picture. At least 1 million species face short term extinction. Declines in biodiversity link to reductions in food supply, fresh water, wood, fiber, genetic resources, medicines and more. Around the world, rates of change in nature are unprecedented, with complex causes including changes in land and sea use; direct exploitation of organisms; climate change; and pollution.
Although threats are greatest in the Global South, our central New Jersey urban watershed is not immune. Loss of forest and freshwater wetland habitat compromise water quality and food sources. Loss of coastal wetland habitat reduces coastal protections, increasing the risk from floods and hurricanes to livelihood, life and property. Loss of soil integrity threatens our “Garden State” status.
The image series below shows an increase in impervious cover in the Lower Raritan Watershed between the years 1995-2012. We see an increase in hard surfaces like roadways, parking lots and roofs over time. What are these hard surfaces replacing? Significant swatches of bio-diverse natural habitat.
An increase in impervious cover is especially hard on our local streams, many of which have already been completed culverted, buried, or otherwise covered up. Increases in impervious cover also negatively impact the surrounding flora and fauna that is crucial to ecosystem health. We know that ecosystems with a wide variety of plants and animals tend to be healthier than those with low levels of biodiversity, and healthy ecosystems are better able to adapt to changing conditions like sea level rise and climate change. We also know that biodiversity provides a significant volume of ecosystem services to urban residents, helping to buffer against nuisances generated by the cities themselves. Those of us who live in urban areas experience directly how green areas of different types provide space for recreation, social contacts, experiencing nature, and education. And we benefit from these spaces in other ways as they filter pollutants, purify water, mitigate flooding, reduce noise and buffer climate extremes like heatwaves.
The image below illustrates the diversity of natural features in the Lower Raritan Watershed. These features include state and federal threatened and endangered species, significant natural habitats as part of the NY-NJ Harbor Estuary, and juxtaposition of geologic features tapering from the volcanic basalt trap rock of the Watchung Mountains in the north, to the Piedmont, to the Coastal Plain.
Pairing the map series that traces changes in impervious cover between 1995-2002 with the map above which shows our remaining environmentally sensitive habitat areas, we see clearly that the special bio-diverse lands we do have left are incredibly vulnerable to being disturbed or degraded by human activities and developments.
Documents like the Intergovernmental Assessment of Biodiversity (2019) and the Strategic Plan for Biodiversity 2011-2020 developed out of The Convention on Biological Diversity (2010), provide broad policy guidance that points us in the direction of future biodiversity targets. The New Jersey Department of Environmental Protection’s Division of Fish and Wildlife developed the State Wildlife Action Plan (2018), providing guidance for diverse entities in cooperation across ownerships to conserve and restore habitat and connect lands and waters. These documents focus significantly on conservation and preservation of undeveloped and vulnerable lands. To be sure, they are important tools and resources on the path to a more bio-diverse New Jersey, nation and planet, but little of the guidance they provide directly informs policy choices and personal action for our urban landscapes.
The Lower Raritan Watershed Partnership believes that in addition to broad policy guidance for conservation and preservation, we need a fundamental shift in collective perspective to see that in the fight to protect biodiversity, cities matter too. With the right form and organization, urban areas can provide significant opportunities to biodiversity, including hosting rare and endangered species and habitat types.
Any shift in perspective must involve broadening our understanding of what “nature” is in cities to include a variety of typically forgotten or neglected spaces. Detention and retention basins, brownfields and contaminated sites, vacant lots, roadside and streamside buffer areas, community gardens, and cemeteries are all potential reservoirs of urban diversity. Much of our work in the Lower Raritan revolves in and around these types of neglected spaces, and much of our work involves implementing Nature Based Solutions and Green Infrastructure. We have adopted Nature Based Solutions and Green Infrastructure approaches because they bring considerations for biodiversity and healthy ecosystem function back to our urban areas and their critical density of population. We believe that by implementing these concepts in our cities, linking healthy ecosystem function in the urban core to its broader watershed, we can center biodiversity at the heart of wider spatial planning and spatial policy making.