Evaluating pollution-related damage and restoration success in urban forests with participatory monitoring and digital tools

Peri-urban forest monitoring requires indicators of vegetation damage. An example is the sacred fir (Abies religiosa) forests surrounding Mexico City, which have been heavily exposed to tropospheric ozone, a harmful pollutant, for over 4 decades. We developed a participatory monitoring system with which local community members and scientists generated data on ozone tree damage. Santa Rosa Xochiac rangers (13) used the digital tool KoboToolBox to record ozone damage to trees, tree height, tree ages, tree condition, tree position, and whether the tree had been planted. Thirty-five percent of the trees (n = 1765) had ozone damage. Younger trees had a lower percentage of foliage damaged by ozone than older trees (p < 0.0001), and asymptomatic trees tended to be younger (p < 0.0001). Symptomatic trees were taller than asymptomatic trees of the same age (R²_c = 0.43, R²_m = 0.27). Involving local communities facilitated forest monitoring and using digital technology improved data quality. This participatory system can be used to monitor forest condition change over time and thus aids restoration efforts driven by government or local communities’ interests, facilitating local decision-making.     

Are Roadkill Hotspots in the Cerrado Equal Among Groups of Vertebrates?

Environmental Management - Understand the spatial distribution of wildlife roadkill is necessary to design mitigation measures minimizing damage to the fauna and the human population. Thus, we...     

Environmental implications of soil remediation using the Fenton process

This work evaluates some collateral effects caused by the application of the Fenton process to 1,1-bis(4-chlorophenyl)-2,2,2-trichloroethane (DDT) and diesel degradation in soil. While about 80% of the diesel and 75% of the DDT present in the soil were degraded in a slurry system, the dissolved organic carbon (DOC) in the slurry filtrate increased from 80 to 880mgl(-1) after 64h of reaction and the DDT concentration increased from 12 to 50microgl(-1). Experiments of diesel degradation conducted on silica evidenced that soluble compounds were also formed during diesel oxidation. Furthermore, significant increase in metal concentrations was also observed in the slurry filtrate after the Fenton treatment when compared to the control experiment leading to excessive concentrations of Cr, Ni, Cu and Mn according to the limits imposed for water. Moreover, 80% of the organic matter naturally present in the soil was degraded and a drastic volatilization of DDT and 2,2-bis(4-chlorophenyl)-1,1-dichloroethylene was observed. Despite the high percentages of diesel and DDT degradation in soil, the potential overall benefits of its application must be evaluated beforehand taking into account the metal and target compounds dissolution and the volatilization of contaminants when the process is applied.     

Counterurbanization: A neglected pathway of forest transition

Human settlement into rural areas (counterurbanization) is generating new patterns of reforestation, with distinctive features compared to the previously considered pathways of forest transition through “economic development” and “forest scarcity”. Here, we discuss the specific features of this neglected pathway of forest recovery and describe the process with the support of study cases around the world. This pathway includes specific motivations (e.g., natural amenities, outdoor recreation), particular socio-economic processes, conflicts between newcomers and locals, and specific ecological outcomes (e.g., a larger proportion of non-native species in the new forests). Although this pathway locally affects small areas, as a widespread and expanding process around the world, counterurbanization could have a growing global effect, with the potential to modify biodiversity, ecosystem services, and cultural values. These novel characteristics should be further explored to better understand the patterns and processes of forest transitions in a context of a globally connected world.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01632-9.     

Degrading permafrost river catchments and their impact on Arctic Ocean nearshore processes

Arctic warming is causing ancient perennially frozen ground (permafrost) to thaw, resulting in ground collapse, and reshaping of landscapes. This threatens Arctic peoples'' infrastructure, cultural sites, and land-based natural resources. Terrestrial permafrost thaw and ongoing intensification of hydrological cycles also enhance the amount and alter the type of organic carbon (OC) delivered from land to Arctic nearshore environments. These changes may affect coastal processes, food web dynamics and marine resources on which many traditional ways of life rely. Here, we examine how future projected increases in runoff and permafrost thaw from two permafrost-dominated Siberian watersheds—the Kolyma and Lena, may alter carbon turnover rates and OC distributions through river networks. We demonstrate that the unique composition of terrestrial permafrost-derived OC can cause significant increases to aquatic carbon degradation rates (20 to 60% faster rates with 1% permafrost OC). We compile results on aquatic OC degradation and examine how strengthening Arctic hydrological cycles may increase the connectivity between terrestrial landscapes and receiving nearshore ecosystems, with potential ramifications for coastal carbon budgets and ecosystem structure. To address the future challenges Arctic coastal communities will face, we argue that it will become essential to consider how nearshore ecosystems will respond to changing coastal inputs and identify how these may affect the resiliency and availability of essential food resources.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01666-z.     

Interview with the mayor of Curitiba on habitat II

The objectives of Habitat II were (1) in the long term to arrest the deterioration of human settlements and create the conditions to achieve improvement in the environment on a sustainable basis, and (2) to adopt a general statement on principles and related Global Action Plan to guide national and international efforts in the next two decades. We have asked the Mayor of Curitiba, Brazil Rafael Greca de Macedo to comment on the conference results. Curitiba is one of the most known example of urban ecological planning.     

MODELING RUNOFF FROM VARIABLE SOURCE AREAS IN HUMID,SHALLOW WATER TABLE ENVIRONMENTS1

ABSTRACT: Variable Source Areas (VSAs) are zones with water saturated soils in forested wetlands fringing streams and creeks. Runoff from these areas is generated by saturation excess after a shallow water table rises and inundates the ground surface. In humid regions, like Florida and the Southeast, VSAs are believed to produce most of the runoff in shallow water table environments. Modeling the spatial extent and temporal fluctuation of a VSA is difficult because the formation of a VSA depends on a number of hydrological and morphological factors like rainfall intensity, soil texture, water table depth, and topographic attributes of the terrain. In this paper, we couple a digital elevation model with a two‐dimensional variable saturation model to illustrate the formation of a VSA at the hillside scale. The topography derived from the digital elevation model forms the upper domain geometry for the two‐dimensional finite element simulations of variable saturated flow. The objectives are: (1) to model the spatial and dynamic fluctuation of a VSA, and (2) to understand the roles of rainfall variability and terrain attributes on the formation of a VSA. Results show that hillsides with shallow water table depths, low saturated hydraulic conductivity, mild slopes, and concave slope curvature were more susceptible to runoff from a variable source. Runoff from a variable source showed little sensitivity to rainfall intensity. In general, landscapes with steep slopes generated a small VSA and a seepage face that vanished rapidly with time. In contrast, flat terrains are more amenable to VSA and retain ground surface inundation for longer periods of time.     

Occurrence of Norovirus GIV in Environmental Water Samples from Belém City,Amazon Region,Brazil

Noroviruses are the major cause of non-bacterial acute gastroenteritis outbreaks in humans, with few reports about the occurrence of the norovirus GIV strain. We investigated the presence of norovirus GIV in surface water (river, bay, and stream) and untreated sewage, and we determined a positivity rate of 9.4 % (9/96). The strains genotyped were GIV.1. To our knowledge, this is the first report of GIV in Brazil.     

Diel and tidal cycles regulate larval dynamics in salt marshes and mangrove forests

Variation in the release and recruitment of larvae of estuarine invertebrates affects the distribution and abundance of adults, as well as trophic interactions in both the plankton and the benthos. Larval release and supply are often timed to environmental cycles such as the diel and tidal cycles. Here, we determined using plankton tows whether the abundance of larvae spanning salt marsh and mangrove habitats across the intertidal landscape varied with diel and tidal cycles. Using three different sampling designs across two sites and within each of two estuaries over a 12-month period, we covered a range of spatial and temporal scales. This allowed us to test the general prediction that densities of meroplankton in the water column would be greater during nocturnal ebb tides than during other phases of the diel or tidal cycle. As predicted, nocturnal ebb tides yielded the highest densities of meroplanktonic larvae and were dominated by first-stage crab zoeae and this finding was most pronounced in the salt marsh. Throughout the course of the year, greater numbers of meroplankters consistently occurred during the ebb tide compared with the flood tide. The densities of other taxa (e.g. gastropods and polychaetes) showed no clear trends with diel or tidal cycles. This study highlights the effects of these pervasive physical cycles on the timing of larval release and supply in the salt marsh–mangrove complex, and emphasises their contribution to the trophic interactions and the dynamics of benthic populations within estuaries.