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With this project, we propose to measure the magnitude of water quality improvement that be attained by changing our current lawn-based landscaping paradigm to one that encourages less-intensive management and allows for a greater abundance and diversity of native flora and fauna. Management practices that could provide such benefits and services include converting areas now in lawn into attractively designed thickets of trees and shrubs; allowing other areas to become managed meadows; reducing mowing, fertilizing, herbiciding and irrigation schedules on areas that will remain lawn; and creating rain gardens in areas of high storm water runoff. <P> The goal of this proposal is to demonstrate the value and feasibility of such innovative watershed management practices by quantifying the improvement in water quality and ecosystem services through their implementation. We will accomplish this by 1) quantifying the ecological and economic benefits to water quality and infiltration, as well as the production of other ecosystem services that result from increasing the biomass, productivity, and diversity of plants in urbanizing watersheds (research component) 2) producing nationally marketed educational videos to train watershed managers, landscape professionals (practitioners, designers, and architects), land owners, the nursery trade, and public officials about the critical functions of plants in watershed management, as well as mentoring undergraduate student projects and opening our research sites to public tours (education component) 3) developing an ecosystem services brochure for public consumption; posting recommendations on a sustainable landscaping website; writing popular press articles about landscape practices that improve water quality; producing interpretative signage to explain landscaping practices at our study sites; conducting tours for homeowners and landscape professionals to demonstrate water quality landscaping practices; presenting landscaping short courses for homeowners, Master Gardeners and landscape professionals; and developing nationally distributed science modules to teach youth and land owners how to generate ecosystem services at home (outreach component). <P>We ask: 1: How does water quantity and quality differ between watersheds draining traditionally-managed lawns versus those in native meadows and forests 2: How do ecosystem services differ between landscapes in traditionally-managed lawns versus those in native meadows and forests 3: What are the economic costs and benefits associated with traditionally-managed lawn landscapes versus those in native meadows and forests
Non-Technical Summary: <BR>Water quality management strategies in urban watersheds have historically focused on intercepting polluted water before it enters waterways rather than preventing its pollution in the first place. We suggest that the opposite approach, curbing pollution at its source, will improve water quality more effectively while simultaneously delivering several additional ecosystem services that are inadequately produced in urban watersheds. Two aspects of urban watersheds are primary sources of non-point source pollution: impervious surfaces and excessive use of turf grass. We will address the latter with a comparison of water quality in six contiguous watersheds that vary in vegetative cover from lawn to meadow to forest cover. Using continuous monitoring and synoptic sampling we will quantify the degree to which replacing lawn with diverse vegetation impacts water quality and retention by 1) reducing fertilizer and herbicide inputs, 2) enabling water infiltration, 3) stabilizing stream base-flow, 4) increasing dissolved oxygen, and 5) decreasing turbidity. To understand both the economic and ecological value of using plant communities to improve water quality, we will 1) compare the costs of installing and maintaining lawns, meadows and forest cover and 2) measure the degree to which alternative landscapes with more vegetation store carbon dioxide, conserve biodiversity, and provide natural pest control and pollination services. Although the ability of plants to improve water quality is well-known, our study is innovative because it will 1) quantify the magnitude of water quality differences among different types of ornamental landscapes, and 2) demonstrate for the first time the interconnectedness between water quality management and the production of other ecosystem services. To help end the disconnect between current landscape practices and water quality management in urban watersheds nationwide, we will disseminate the results of our comparisons through a variety of local and national educational and extension products. This is an integrated approach to water quality management that synergistically combines expertise in hydrology, water quality, economics, ecology, entomology, horticulture, extension, and landscape design to address water quality management from a holistic perspective. It is an apt and timely project as there is currently an increasing awareness of the need to improve ecosystem function in urban settings. <P> Approach: <BR> We will conduct this study at Winterthur Museum, Garden and Library (WMGL) (http://www.winterthur.org/), an 809 ha public garden located in northern Delaware. This site provides the opportunity to compare water quality management strategies in several contiguous, multi-hectare watersheds in which separate streams are impacted by traditionally mowed landscape areas or by sustainably managed landscapes (meadows, forests and landscape beds). The garden receives 116,000 visitors per year, providing built-in opportunities for public education at the study site through permanent interpretive signage, workshops, and expert-guided tours. We will also manipulate Applecross, a suburban development adjacent to Winterthur. Applecross, was built using bioswales and meadow corridors to buffer nearby streams. By working directly with several homeowners to develop demonstration sites on their properties, we will provide examples of how sustainable landscapes can be created and managed to improve water quality and other ecosystem services without losing aesthetic appeal. The proximity to Winterthur and the existing focus on water quality make Applecross an ideal suburban development to demonstrate sustainable landscaping concepts on a suburban lot scale. Water quantity and quality monitoring and sampling will be conducted using a combination of two approaches: (1) continuous monitoring and (2) synoptic sampling. Continuous water monitoring will be performed on the two main treatment watersheds - W4 (traditional lawn) and W3 (native meadow). This will include continuous stream discharge monitoring and continuous recording of stream-water physiochemical parameters at the outlet of the streams draining the watersheds. We will use three taxa [plants, Lepidoptera (moths and butterflies), and breeding birds] as surrogates for total biodiversity when comparing the impact of landscape vegetation on watershed biodiversity. We will use line-intercept sampling to estimate vegetation cover, biomass, and structure as a measure of the overall composition of vegetation cover. The abundance and richness of nesting pollinators will be compared each year of the project among our six watersheds by counting reproducing pollinators along 10 1m wide transects that are evenly spaced across each watershed. We will estimate all standing and downed trees in each watershed. To estimate non-tree biomass (turf grass, meadow, forest floor) we will remove, dry and weigh all vegetation and litter to mineral soil level within ten randomly selected 0.5m quadrats in each cover type. The economics of landowner property management choices involve four aspects: (1) the knowledge of the benefits and costs of each management practice; (2) the actual costs to the landowners of implementing practices; (3) the private benefits to the landowners of implementing practices; and (4) the received benefits and costs by neighbors. The research, education, and outreach components of this proposal address the first aspect in detail. Researchers will develop three major educational products including a video, science curriculum and sample designs for professional designers and homeowners.