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Governing urban green infrastructure is challenging due to the various institutions, interests and values involved in municipal planning, decision-making and management processes. Indicators of urban ecosystem services and green infrastructure may support the development of mutual understanding among municipal authorities and the creation of usable information. In this study, the application of ecosystem services (ES) indicators is approached through knowledge-brokering and boundary work theories. We apply a set of GIS-based ES indicators in a medium-sized Finnish city in a collaborative process with local civil servants in order to provide overarching information on the green infrastructure and to enhance dialogue among civil servants. We present the three phases of the indicator application process (conceptual, instrumental and reflection phases) describe the indicator-based boundary work, and identify factors affecting the process. The results highlight the importance of collaboration and active knowledge brokering in indicator applications, involving a combination of conceptual and methodological expertise on the ES approach with knowledge on local environment and relevant policy and planning issues, as well as iterative reflection throughout the indicator application process. Finally, some critical characteristics of boundary work in applying the ES indicators are proposed. [ABSTRACT FROM AUTHOR]

Abstract: Indicators describing sustainability and, more recently, well-being have raised considerable interest throughout the world. Much conceptual and empirical research exists focusing on the criteria for sustainability and development of indicators, while relatively few studies examine the actual use and influence of indicators. Employing document analysis and interviews of key actors, we explore the use of sustainable development indicators at national and EU level and draw forth lessons relevant for topical discussion of the measurement of human well-being. We apply a conceptual model of three main types of indicator use: instrumental, conceptual, and political. The results indicate that the use of sustainability indicators is mainly confined to the ‘indicator circuit’ formed by indicator-developers themselves and actors obliged to use the indicators. The results suggest that direct instrumental use of indicators shows limited potential, whereas conceptual use is the key for enhanced indicator influence in the long term. Political use of indicators cannot be controlled by the indicator-developers. [Copyright &y& Elsevier]

We simulated the REA system with dynamic deadband to study numerical value and the effect of atmospheric conditions on the empirical constant β which relates vertical flux to concentration difference between updrafts and downdrafts. We found that the value of β depends only weakly on the friction velocity and atmospheric stability. In agreement with previous studies, the median value obtained for a system with dynamic deadband proportional to 0.5 times the running mean of the standard deviation of vertical wind speed was β =0.42±0.03. For a single half-hour measurement one has to consider the large uncertainty of ±0.2. According to our study, the dynamic deadband enables the use of a constant value of β in flux calculation. [Copyright &y& Elsevier]

Although grazing is the primary land use in the savanna lowland of southern Kenya, the effects of grazing on soil carbon dioxide flux (R S) remain unclear. A 12-month study was conducted from January to December 2020 on the effects of six grazing intensities sites (overgrazed (OG), heavily grazed (HG), moderately grazed (MG), moderately to lightly grazed (M-LG), lightly grazed (LG) and no grazing (NG)) on R S on. A camera trap was used to monitor the total number of animals at each site, indicating the grazing intensity. Weekly measurements of R S were taken using static greenhouse gas chambers along with simultaneous measurements of soil temperature (T S) and volumetric soil water content (W S) (depth of 5 cm). Mean R S at HG, MG, M-LG and LG sites was approximately 15–25% higher than at NG and OG sites (p < 0.001). Mean W S increased with decrease in grazing especially in the dry season, while T S increased with increase in grazing. We observed bimodal temporal variation in R S and W S due to two wet seasons in the year. Thus, variation in R S across the study period followed the changes in W S rather than those in T S. Mean values of R S in the wet seasons were significantly higher (> 45%) than those in the dry seasons, and W S accounted for 71% of the temporal variability in R S (p < 0.05). In addition, the enhanced vegetation index (EVI, interpreted as a proxy for vegetation cover) explained 60% of the variance of R S , and W S and EVI together explained 75%. EVI showed a negative relationship (p < 0.05) with animal intensity, indicating that more grazing reduced vegetation cover and, consequently, soil organic carbon and biomass. Soil bulk density was lower at less grazed sites. While R S variability was unaffected by total nitrogen content, pH, and texture, correspondence analysis demonstrated that the main factors influencing R S dynamics across the year under different grazing intensities were W S and vegetation cover. Our results contribute to closing the existing knowledge gap regarding the effects of grazing intensity on R S in East Africa savannas. Therefore, this information is of great importance in understanding carbon cycling in savanna grassland, as well as the identification of the potential consequences of increasing land pressure caused by rising livestock numbers, and will assist in the development of climate-smart livestock management in East Africa. • Soil CO 2 fluxes decreased with an increase in grazing. • Grazing reduced the vegetation cover, herbaceous aboveground biomass, and increased bulk density. • Enclosure no grazing had lower soil CO 2 fluxes due to lower soil temperturestemperatures and understorey. • Volumetric soil water content and vegetation cover explained the temporal variation in soil CO 2 fluxes. • Results are important in developing climate-smart pastoralism transformation in East Africa. [ABSTRACT FROM AUTHOR]

Boreal/arctic wetlands are dominated by diverse plant species, which vary in their contribution to CH 4 production, oxidation and transport processes. Earlier studies have often lumped the processes all together, which may induce large uncertainties into the results. We present a novel model, which includes three vegetation classes and can be used to simulate CH 4 emissions from boreal and arctic treeless wetlands. The model is based on an earlier biogeophysical model, CH4MOD wetland . We grouped the vegetation as graminoids, shrubs and Sphagnum and recalibrated the vegetation parameters according to their different CH 4 production, oxidation and transport capacities. Then, we used eddy-covariance-based CH 4 flux observations from a boreal (Siikaneva) and a subarctic fen (Lompolojänkkä) in Finland to validate the model. The results showed that the recalibrated model could generally simulate the seasonal patterns of the Finnish wetlands with different plant communities. The comparison between the simulated and measured daily CH 4 fluxes resulted in a correlation coefficient ( R 2 ) of 0.82 with a slope of 1.0 and an intercept of − 0.1 mg m − 2 h − 1 for the Siikaneva site (n = 2249, p < 0.001) and an R 2 of 0.82 with a slope of 1.0 and an intercept of 0.0 mg m − 2 h − 1 for the Lompolojänkkä site (n = 1826, p < 0.001). Compared with the original model, the recalibrated model in this study significantly improved the model efficiency (EF), from − 5.5 to 0.8 at the Siikaneva site and from − 0.4 to 0.8 at the Lompolojänkkä site. The simulated annual CH 4 emissions ranged from 7 to 24 g m − 2 yr − 1 , which was consistent with the observations (7–22 g m − 2 yr − 1 ). However, there are some discrepancies between the simulated and observed daily CH 4 fluxes for the Siikaneva site ( RMSE = 50.0%) and the Lompolojänkkä site ( RMSE = 47.9%). Model sensitivity analysis showed that increasing the proportion of the graminoids would significantly increase the CH 4 emission levels. Our study demonstrated that the parameterization of the different vegetation processes was important in estimating long-term wetland CH 4 emissions. [ABSTRACT FROM AUTHOR]

Holocene peatland development and associated carbon (C) dynamics were reconstructed for a southern boreal Finnish peatland complex with fen and bog areas. In order to assess the role of local factors and long-term allogenic climate forcing in peatland development patterns, we studied a total of 18 peat cores and reconstructed vertical peat growth and lateral peat area expansion rates, the C accumulation rate (CAR), past vegetation composition and past methane (CH 4 ) fluxes. We combined fossil plant data with measured contemporary CH 4 flux – vegetation relationship data to reconstruct CH 4 fluxes over time. When these reconstructions were added to the CAR estimations, a more complete picture of Holocene-scale C dynamics was achieved. Basal peat ages showed that expansion of the peat area was rapid between 11,000 and 8000 cal. BP, but decreased during the dry mid-Holocene and is probably currently limited by basal topography. A similar pattern was observed for peat growth and CAR in the fen core, whereas in the bog core CAR increased after ombrotrophication, i.e. after 4400 cal. BP. The effect of fire on vegetation and CAR was more conspicuous at the bog site than at the fen site. The CH 4 flux reconstructions showed that during the Holocene CH 4 emissions at the fen site decreased from 19 ± 15 to 16 ± 8 g CH 4 m −2 yr −1 and at the bog site from 20 ± 15 to 14 ± 8 g CH 4 m −2 yr −1 . Our results suggest that a combination of changing climate, fire events and local conditions have modified the autogenic peatland development and C dynamics. [ABSTRACT FROM AUTHOR]

Abstract: We determined the accuracy of the dynamic chamber system for measuring VOC emissions of trees and soil in the field at SMEAR II station, Hyytiälä, Southern Finland. The study was based on creating a known source of different VOCs inside the chamber and measuring the concentration dynamics in the chamber by a proton transfer reaction mass spectrometer (PTR-MS) connected to the chamber. The chamber system underestimated the artificially generated VOC emission rates at varying degree. In isoprene, monoterpene and many oxygenated VOCs the underestimation was 5–30% but in some compounds with protonated mass >100 amu the signal was almost completely lost. The underestimation mainly originated in the chamber but the length of the sample tubing also affected the observed magnitude of the standard gas emission. The systematic error was higher at high relative humidity than in drier conditions, which suggests that the thickness of the water film adsorbed on the chamber inner surfaces contributes to the VOC loss rate in the chamber. Increasing the length of the chamber closure time slightly reduced the systematic underestimation of emission in most of the studied compounds although the underestimation persisted for at least 10 min. A dynamic chamber setup enables measurement of VOC emissions with good accuracy and precision while minimising the disturbance of the chamber to the object being measured. [Copyright &y& Elsevier]