ESA can be a society for all ecologists

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/117231/1/fee201412291.pd

The Benefits and Limits of Urban Tree Planting for Environmental and Human Health

Many of the world's major cities have implemented tree planting programs based on assumed environmental and social benefits of urban forests. Recent studies have increasingly tested these assumptions and provide empirical evidence for the contributions of tree planting programs, as well as their feasibility and limits, for solving or mitigating urban environmental and social issues. We propose that current evidence supports local cooling, stormwater absorption, and health benefits of urban trees for local residents. However, the potential for urban trees to appreciably mitigate greenhouse gas emissions and air pollution over a wide array of sites and environmental conditions is limited. Consequently, urban trees appear to be more promising for climate and pollution adaptation strategies than mitigation strategies. In large part, this is due to space constraints limiting the extent of urban tree canopies relative to the current magnitude of emissions. The most promising environmental and health impacts of urban trees are those that can be realized with well-stewarded tree planting and localized design interventions at site to municipal scales. Tree planting at these scales has documented benefits on local climate and health, which can be maximized through targeted site design followed by monitoring, adaptive management, and studies of long-term eco-evolutionary dynamics.Peer reviewe

Előzetes eredmények városi talajok lebontó hatásfokának vizsgálatáról (GLUSEEN-Projekt, Budapest)

A „Global Urban Soil Ecology and Education” hálózat előkészítő kutatása második éve folyik – a világ 4 régiójának 5 helyszínén –, Magyarország részvételével. A kutatás célja az ún. „konvergencia hipotézis” tesztelése különböző minőségű/zavartságú városi talajok szerves anyag lebontási hatásfokán keresztül. A konvergencia hipotézis szerint a természetes ökoszisztémák az urbanizáció hatására hasonló irányú változást mutatnak globális szinten. A cél mind tudományos igényű kutatások, mind az érdeklődő lakosság bevonására alkalmas egyszerű, könnyen kivitelezhető, költséghatékony módszerek kidolgozása, tesztelése. A kutatás során 4 élőhelytípust (5–5 ismétlésben) jelöltünk ki: 1) erősen zavart (ruderális), 2) városi gyep, 3) az urbanizáció eredményeként fragmentálódott erdőfoltok és 4) referenciaként szolgáló természetközeli erdők területei. A szervesanyag bomlásának mértékét 2013-ban leásott teafilterekkel vizsgáltuk, amelyeket 4, 6, 10, 12 hónap után gyűjtöttünk vissza. Eredményeink szerint a 6. hónaptól szignifikáns különbség mutatkozott az élőhelytípusok között a lebontási sebességben (F = 11,238; p < 0,0001), ami a városi gyepeken és ruderális élőhelyeken volt a legnagyobb. Ez összhangban van a többi 4 városban kapott eredménnyel, ami alátámasztja a konvergencia hipotézist: a különböző éghajlatú, alapkőzetű talajok kémhatása és humusztartalma az erősen zavart és városi gyep élőhelyek esetén azonos irányú változást mutatnak világszerte

Down by the riverside: urban riparian ecology

Riparian areas are hotspots of interactions between plants, soil, water, microbes, and people. While urban land use change has been shown to have dramatic effects on watershed hydrology, there has been surpris- ingly little analysis of its effects on riparian areas. Here we examine the ecology of urban riparian zones, focusing on work done in the Baltimore Ecosystem Study, a component of the US National Science Foundation's Long Term Ecological Research network. Research in the Baltimore study has addressed how changes in hydrology associated with urbanization create riparian "hydrologic drought" by lowering water tables, which in turn alters soil, vegetation, and microbial processes. We analyze the nature of past and cur- rent human interactions with riparian ecosystems, and review other urban ecosystem studies to show how our observations mirror those in other cities

A global comparison of surface soil characteristics across five cities: a test of the urban ecosystem convergence hypothesis

As part of the Global Urban Soil Ecology and Education Network and to test the urban ecosystem convergence hypothesis, we report on soil pH, organic carbon (OC), total nitrogen (TN), phosphorus (P), and potassium (K) measured in four soil habitat types (turfgrass, ruderal, remnant, and reference) in five metropolitan areas (Baltimore, Budapest, Helsinki, Lahti, Potchefstroom) across four biomes. We expected the urban soil characteristics to “converge” in comparison to the reference soils. Moreover, we expected cities in biomes with more limiting climatic conditions, or where local factors strongly affect soil characteristics, would exhibit the greatest variance across soil types within and among cities. In addition, soil characteristics related to biogenic factors (OC, TN) would vary the most because of differences in climate and human efforts to overcome limiting environmental conditions. The comparison of soils among and within the five cities suggests that anthropogenic, and to a lesser degree native, factors interact in the development of soils in urban landscapes. In particular, characteristics affected by anthropogenic processes and closely associated with biogenic processes (OC, TN) converged, while characteristics closely associated with parent material (K, P) did not converge, but rather diverged, across all soil habitat types. These results partially supported the urban ecosystem convergence hypothesis in that a convergence occurred for soil characteristics affected by climatic conditions. However, the divergence of K and P was unexpected and warrants adjusting the hypothesis to account for variations in anthropogenic effects (e.g., management) that may occur within soil habitat types impacted by human

Spatial variability and uncertainty of soil nitrogen across the conterminous United States at different depths

Abstract Soil nitrogen (N) is an important driver of plant productivity and ecosystem functioning; consequently, it is critical to understand its spatial variability from local‐to‐global scales. Here, we provide a quantitative assessment of the three‐dimensional spatial distribution of soil N across the United States (CONUS) using a digital soil mapping approach. We used a random forest‐regression kriging algorithm to predict soil N concentrations and associated uncertainty across six soil depths (0–5, 5–15, 15–30, 30–60, 60–100, and 100–200 cm) at 5‐km spatial grids. Across CONUS, there is a strong spatial dependence of soil N, where soil N concentrations decrease but uncertainty increases with soil depth. Soil N was higher in Pacific Northwest, Northeast, and Great Lakes National Ecological Observatory Network (NEON) ecoclimatic domains. Model uncertainty was higher in Atlantic Neotropical, Southern Rockies/Colorado Plateau, and Southeast NEON domains. We also compared our soil N predictions with satellite‐derived gross primary production and forest biomass from the National Biomass and Carbon Dataset. Finally, we used uncertainty information to propose optimized locations for designing future soil surveys and found that the Atlantic Neotropical, Pacific Northwest, Pacific Southwest, and Appalachian/Cumberland Plateau NEON domains may require larger survey efforts. We highlight the need to increase knowledge of biophysical factors regulating soil processes at deeper depths to better characterize the three‐dimensional space of soils. Our results provide a national benchmark regarding the spatial variability and uncertainty of soil N and reveal areas in need of a better representation

Community Knowledge and Concerns About Urban Soil Science, Practice, and Process: Perspectives From the Healthy Soils for Healthy Communities Initiative in Los Angeles, CA, United States

Urban soil systems research has largely relied on the narrative that soils provide ecosystem services to human populations and should be studied and managed to maximize their potential value in regards to such services. However, soil scientists have not adequately engaged with diverse stakeholders to understand the needs, opportunities, and challenges related to urban soil systems. This disconnect has resulted in urban soil system research agendas that are potentially misaligned with the needs of the communities in which they are situated. Community engagement in the priorities-setting stage of research development can create research agendas that more closely align with community needs. Here we report on findings from the Healthy Soils for Healthy Communities Initiative in which community perceptions, needs, and concerns regarding soils in Los Angeles (LA) County, California, United States were measured through four county-wide online surveys with residents, educators, policy-makers, and professionals and a series of virtual focus groups with key community representatives. The online surveys revealed that the majority of LA County residents (76%) are very or extremely concerned about soil contaminants and pollution. Likewise, 70% of policy-makers and 77% of LA County professionals are highly concerned about soil contamination. In contrast, fewer LA County educators (48%) are concerned about soil contaminants and pollution. Even though 85% of LA County residents surveyed maintain some kind of green space, 70% self-report that their knowledge regarding factors impacting soil health is low. The focus groups revealed several themes present across stakeholder groups including a need for: (1) accessible and transparent soil data and testing; (2) effective community engagement and streamlined communication that centers underserved communities; and (3) building alliances among community, policy, businesses, and science professionals and leveraging connections among organizations, individuals, and agencies that are focused on soil. The findings from this study have informed the future direction of urban soil research and community science in the region. The process of engaging communities in defining research agendas can serve as a model for other cities providing an opportunity to not only improve the relevance and impact of urban soil research, but also improve the sustainability of urban soil systems