While the utility of these scores could be improved with faunal densities, they provide preliminary insight about what types of microhabitats and which environmental variables may be important to specific services at specific sites. Methane seeps have been recognized as essential fish habitat and this trait-based approach could provide additional evidence for spatial protections. The focus on ecosystem services provides a targeted effort that can help guide research and management priorities. In the case of the Del Mar seep, Grupe et al. found higher densities of commercially-valuable species at the active seep than in adjacent, background areas. Our results somewhat contrast because we found no significant differences in ecosystem services scores among the active seep and background area during the Del Mar dive. This suggests that the Del Mar area, in general, contributes more to fisheries and carbon services than our other study sites. However, background areas could potentially be influenced by the seep through movement of chemicals and animals from the seep to adjacent areas . One drawback to using deep-sea imagery for trait-based ecosystem services assessment is the need for visual evidence. The traits in Table 4.3 are not exhaustive of characteristics that can contribute to fisheries or carbon services, but they were ascertainable from our dive videos. While deep-sea imagery may not be able to confirm regulating services,vertical farming tower for sale like metatranscriptomics could , it does provide insight on animal behavior that can support ecosystem services. For example, mid-water fish would often be seen near the benthos and swimming into it , which has been previously observed .

This could potentially represent an important benthic-pelagic interaction that contributes to carbon export.Expensive and limited ship time can make it difficult to collect ideal video data. The need to juggle multiple scientific goals during each ROV dive makes it impractical to conduct quantitative visual transects, and to generate sufficient number of replicate transects. This can create downstream constraints for data analysis such as lack of quantitative measures of densities and difficulty standardizing observations. Best practices for collecting pictures and videos from deep-sea sampling instruments could be useful . Random and independent sampling could facilitate data analysis. Replicates could also be useful, in which cabled observatories may be appropriate . ROV and AUV transects should be conducted with consistent altitude, zoom, and speed, as well as with a scale for size . The resulting data can then be used to calculate faunal densities and other diversity metrics . A quantitative transect would also allow for comparison among locations and time periods . Accurate maps of the seafloor before dive operations can help ensure best use of time , but perhaps most important are the designation of detailed scientific goals and objectives prior to surveying.Environmental measurements should be made in association with imagery being taken. Physical and chemical properties, such as temperature, oxygen, and hydrogen sulfide at seeps, are important parameters that help shape the biological communities . Porewater chemistry influences the sediment community , which can contribute to fisheries services and carbon services . Scientific tools exist to assess water chemistry such as in situ mass spectrometers that can be mounted on ROVs and niskin bottles that can be used to sample water at discrete depths. These environmental properties can help explain differences in diversity and distribution, and provide insight on how communities may change with human impact such as climate change .

As imaging technology continues to advance, the resolution of pictures and videos becomes increasingly helpful for post-analysis . Imagery should be analyzed consistently, which may mean cross-referencing protocols and morphotypes if more than one person is conducting the analysis. Human bias is inherent to current image analysis but can be minimized with training . As more deep sea imagery is analyzed and libraries are produced, there are possibilities to incorporate machine learning algorithms in collaboration with computer science and programming . Machine learning techniques could facilitate mining of existing deep-sea imagery data. They often sit in labs untouched, representing an underutilized source of knowledge. These pictures and videos provide an opportunity to generate knowledge for habitats that are rarely visualized and are data-limited. Imagery is also routinely collected for non-biological purposes, such as instrument deployment, which could be an additional source of data.The approach developed in this study can serve as an environmental decision-making tool, such as in the designation of spatial protections, consideration of ecosystem service trade offs, and understanding of context-dependent roles of methane seeps. This analysis can identify areas of high ecosystem services provision, such as the Del Mar seep that had relatively high fisheries and carbon scores, which may be important for designating essential fish habitat or marine-protected areas . An ecosystem-services approach can also investigate trade offs that may need to be considered during the environmental decision-making process . For example, if methane seeps provide differential ecosystem services, one prioritization metric for spatial protections could be weighted ecosystem services scores . Lastly, results from this paper advance our understanding of ecosystem services associated with methane seeps. They highlight the context-dependent role of methane seeps in providing fisheries and carbon services along environmental gradients. For example, while the combination of seepage and low oxygen seemed to suppress ecosystem services scores at Point Dume, the Palos Verdes and Del Mar ecosystem services seemed to benefit from at least some seep activity.

Development and urbanization transform coastal landscapes by replacing vegetation with impermeable surfaces. Subsequent precipitation events can lead to decreased water infiltration, modified water flows, and introduction of contaminants into storm water runoff . As a result, flooding and property damage, increased safety and health risks, and environmental damage can occur . Urban planners and developers have traditionally addressed storm water runoff issues by building drainage systems that connect directly to large bodies of water or treatment plants. The former have been found to further alter hydrology and degrade water quality , while the latter can be energetically and chemically intensive . Natural storm water treatment systems are emerging as an alternative storm water management strategy . NTS are human-made systems that use natural processes to capture and treat storm water runoff. They come in different forms: bio-retention systems , infiltration basins and trenches, permeable pavements, dry wells and ponds, treatment wetlands, and combinations. Table 5.1 provides a summary,hydroponic vertical farm although there are differing opinions on what constitutes an NTS . Additionally, some of the listed systems can also treat wastewater, functioning in similar ways but obtaining water from different sources. This paper focuses primarily on bio-retention systems because they host biological communities as part of their design. Because NTS function as built ecosystems, they can support diverse ecosystem services, defined as direct and indirect benefits humans obtain from ecosystems . Ecosystem services associated with NTS have long been acknowledged , but they have largely been ignored by monitoring programs and economic valuation efforts, which have been limited to targeted water functions. Co-benefits have been described for other green spaces such as offsetting carbon emissions , cooling local temperatures , cultural services , and benefits to human health and well-being . The incorporation of ecosystem services and other co-benefits into environmental decision-making can present urban planners and developers with additional benefits, costs, and trade offs to consider in order to make optimized decisions . We use Los Angeles County as a case study because it experiences periodic water crises, hosts a dense human population near the coast, and has policy in place to encourage the use of NTS. There are spatial and temporal mismatches in the supply and demand for water in California, most precipitation occurring remotely from agricultural and metropolitan hubs that need consistent sources of water irrigated and imported . Additionally, California droughts and water shortages are predicted to increase in frequency and magnitude due to anthropogenic climate change .

As a state, California has passed several propositions to protect water supply and quality . In 2004, Los Angeles passed Proposition O which allowed the city to issue up to $500 million to fund projects that increase local water quality . In 2012, Los Angeles adopted its Low Impact Development Ordinance requiring development and redevelopment projects that alter impervious area to mitigate runoff by capturing precipitation and utilizing natural resources where possible. As a result of these environmental conditions and political momentum, green infrastructure and NTS have been broadly distributed throughout Los Angeles County and continue to be implemented. NTS are designed to capture storm water runoff for infiltration or reuse , and have been shown to be effective . Most systems are oriented vertically, using gravity to direct water flow through several layers that generally consist of a ponding area with vegetation, porous filter media, and a drainage zone . Infiltration rates of a system can vary widely depending on variables such as size , age , filter media , and other design factors . Vegetation also plays a role by intercepting precipitation and water flows , and preventing clogging of filter media to maintain infiltration capacity . Additionally, evapotranspiration by plants can account for 15- 20% of inflow . Urban areas with low permeable surface area can be prone to flooding and changes in groundwater recharge . Los Angeles County lacks infrastructure to handle large volumes of storm water , and flooding can occur when unexpectedly high precipitation occurs. This issue occurs in a state that experiences episodic drought , highlighting the need for proper storm water management and use. Targeted storm water infiltration by NTS can provide ecosystem services that help address these challenges.By altering landscapes and hydrology, urbanization can lead to increased flood risk caused by heavy precipitation and storm surge . NTS have been shown to significantly reduce runoff volume and magnitude of high-flow events by capturing and storing storm water runoff. Hatt et al. found reductions in runoff volume of 33% on average, as well as peak flow reductions of at least 80% in three bio-retention systems in Australia. In another field study, Davis reported mean peak flow reductions of 49% and 58% in two test bio-retention systems, as well as delays in flow peaks which can provide urban managers with time to put mitigation measures in place. Most Los Angeles NTS showed visual indicators of flood control services: permeable surfaces that allow for water infiltration, graded landscaping to help direct runoff, and ponding areas designed to temporarily store water. For example, Elmer Avenue Green Street was constructed specifically to address street flooding during precipitation events by incorporating bioswales, biofilters, permeable pavements, and rain barrels . However, additional information is needed in order to quantify these services. Measurements for flood hazard may be relevant , as well as those for flood vulnerability . Spatial models have also been developed, mapping urban surfaces to estimate infiltration capacity . The value of flood control has been extensively studied in the context of wetlands , generally by assessing differences in property damage along a spectrum of wetland area . Brander et al. conducted a meta-analysis to estimate the value of flood control by wetlands which resulted in a median of $20-30 1995 USD per hectare annually. Watson et al. estimated a net present value of less than $100 USD per hectare of wetland annually. NTS usually operate at smaller spatial scales than major wetland restoration projects so the main unknown here is whether NTS of different designs provide more localized flood control.Groundwater is used by more than half of the population in the U.S. and its recharge is an essential component of the water cycle . Major sources of recharge in urban environments include runoff infiltration, and leakages from the water supply and sewage systems . Urbanization can decrease groundwater recharge due to the installation of impermeable surfaces . However, the importation of large volumes of water to meet demand in highly-populated urban areas also leads to significant leakages and recharge . These changes can also degrade water quality, e.g. leakage from sewage systems, saltwater intrusion due to lowering of the water table . NTS can contribute to groundwater recharge by providing permeable surfaces and pore space in their filter media that allow storm water runoff to pass into the soil subsurface.