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The article discusses philosopher Hans Jonas's concept of environmental ethics. Jonas argues that all ethical relations derive from the basic fact that man is embedded in natural and social relations, and the ethical feature of these relations is not established by the subjectivity of human beings. It is stated that the increasing climatic changes on the earth has resulted in inaccurate predictions about the development of the biosphere in general.

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Variability of chlorophyll concentration in the ocean is one of the most important components of the primary production process on the planet. To preserve the biosphere and to make appropriate use of it, it is imperative to have a deep insight into the long-term dynamics of the primary production on the planet. To investigate the dynamics of chlorophyll concentration based on satellite data, the Institute of Biophysics (Russian Academy of Sciences, Siberian Branch) has developed a geoinformation system. It was used to detect the areas in the global ocean that are quasistationary in relation to seasonal dynamics of chlorophyll concentration. Areas such as these, found in the Indian Ocean, are described in this work. These areas form the basis for the analysis of long-term dynamics of chlorophyll concentration. In these quasistationary zones systematic monitoring of phytopigment concentration is conducted by space-borne and marine craft. The work presents long-term satellite-based data on the space distribution of anomalous deviations of chlorophyll concentration in the ocean. An anomaly criterion is proposed and maps of Pacific Ocean areas with a high probability of anomalies are presented. [ABSTRACT FROM AUTHOR]

One was the Planetary Boundaries framework, introduced by Johan Rockström and colleagues in 2009, which aims to provide a natural-science based framework for describing a Holocene-like state of the Earth System and the intrinsic boundaries of the Earth System that should not be transgressed if such a stable state is to be maintained (Rockström et al. [10]). Introducing the Anthropocene: The human epoch: This article belongs to Ambio's 50th Anniversary Collection. The other is the polycentric governance systems approach introduced by the late Elinor Ostrom ([9]), which, in the context of the S et al. paper, was proposed as a more appropriate governance system for the Anthropocene than the present governance systems that are driving us deeper towards a planetary crisis. The SCM paper foreshadowed the debate on the start date for the Anthropocene, which became prominent from 2009 with the formation then of the Anthropocene Working Group to explore the Anthropocene as a potential new interval in the Geologic Time Scale (AWG [1]). [Extracted from the article]

This paper gives an overview over all currently available data sets for the European Long-term Ecosystem Research (eLTER) monitoring site Gesäuse-Johnsbachtal. The site is part of the LTSER platform Eisenwurzen in the Alps of the province of Styria, Austria. It contains both protected (National Park Gesäuse) and non-protected areas (Johnsbachtal). Although the main research focus of the eLTER monitoring site Gesäuse-Johnsbachtal is on inland surface running waters, forests and other wooded land, the eLTER whole system (WAILS) approach was followed in regard to the data selection, systematically screening all available data in regard to its suitability as eLTER's Standard Observations (SOs). Thus, data from all system strata was included, incorporating Geosphere, Atmosphere, Hydrosphere, Biosphere and Sociosphere. In the WAILS approach these SOs are key data for a whole system approach towards long term ecosystem research. Altogether, 54 data sets have been collected for the eLTER monitoring site Gesäuse-Johnsbachtal and included in the Dynamical Ecological Information Management System – Site and Data Registry (DEIMS-SDR), which is the eLTER data platform. The presented work provides all these data sets through dedicated data repositories for FAIR use. This paper gives an overview on all compiled data sets and their main properties. Additionally, the available data are evaluated in a concluding gap analysis with regard to the needed observation data according to WAILS, followed by an outlook on how to fill these gaps. [ABSTRACT FROM AUTHOR]

The Coupled Climate-Economy-Biosphere (CoCEB) model described herein takes an integrated assessment approach to simulating global change. By using an endogenous economic growth module with physical and human capital accumulation, this paper considers the sustainability of economic growth, as economic activity intensifies greenhouse gas emissions that in turn cause economic damage due to climate change. Different types of fossil fuels and different technologies produce different volumes of carbon dioxide in combustion. The shares of different fuels and their future evolution are not known. We assume that the dynamics of hydrocarbon-based energy share and their replacement with renewable energy sources in the global energy balance can be modeled into the 21st century by use of logistic functions. Various climate change mitigation policy measures are considered. While many integrated assessment models treat abatement costs merely as an unproductive loss of income, we consider abatement activities also as an investment in overall energy eficiency of the economy and decrease of overall carbon intensity of the energy system. The paper shows that these efforts help to reduce the volume of industrial carbon dioxide emissions, lower temperature deviations, and lead to positive effects in economic growth. [ABSTRACT FROM AUTHOR]

The Ent Terrestrial Biosphere Model (Ent TBM) is a mixed-canopy dynamic global vegetation model developed specifically for coupling with land surface hydrology and general circulation models (GCMs). This study describes the leaf phenology submodel implemented in the Ent TBM version 1.0.1.0.0, coupled to the carbon allocation scheme of the Ecosystem Demography (ED) model. The phenology submodel adopts a combination of responses to temperature (growing degree days and frost-hardening), soil moisture (linearity of stress with relative saturation), and radiation (light length). Growth of leaves, sapwood, fine roots, stem wood, and coarse roots is updated on a daily basis. We evaluate the performance in reproducing observed leaf seasonal growth as well as water and carbon fluxes for four plant functional types at five Fluxnet sites, with both observed and prognostic hydrology, and observed and prognostic seasonal leaf area index. The phenology submodel is able to capture the timing and magnitude of leafout and senescence for temperate broadleaf deciduous forest (Harvard Forest and Morgan-Monroe State Forest, US), C3 annual grassland (Vaira Ranch, US), and California oak savanna (Tonzi Ranch, US). For evergreen needleleaf forest (Hyytiäla, Finland), the phenology submodel captures the effect of frost-hardening of photosynthetic capacity on seasonal fluxes and leaf area. We address the importance of customizing parameter sets of vegetation soil moisture stress response to the particular land surface hydrology scheme. We identify model deficiencies that reveal important dynamics and parameter needs. [ABSTRACT FROM AUTHOR]

Land surface albedo, the fraction of incoming solar radiation reflected by the land surface, is a key component of the earth system. This study evaluates snow-free surface albedo simulations by the Community Atmosphere Biosphere Land Exchange (CA- BLEv1.4b) model with the Moderate Resolution Imaging Spectroradiometer (MODIS) albedo. We compare results from two offline simulations over the Australian continent, one with prescribed background snow-free and vegetation-free soil albedo derived from MODIS (the control), and the other with a simple parameterisation based on soil moisture and colour. The control simulation shows that CABLE simulates albedo over Australia reasonably well, with differences with MODIS within an acceptable range. Inclusion of the parameterisation for soil albedo however introduced large errors for the near infra red albedo, especially for desert regions of central Australia. These large errors were not fully explained by errors in soil moisture or parameter uncertainties, but are similar to errors in albedo in other land surface models which use the same soil albedo scheme. Although this new parameterisation has introduced larger errors as compared to prescribing soil albedo, dynamic soil moisture-albedo feedbacks are now enabled in CABLE. Future directions for albedo parameterisations development in CABLE are discussed. [ABSTRACT FROM AUTHOR]

Purpose: The environmental problems which have been deepening in recent decades, i.e. climate change or the degradation of the biosphere, are creating a new reality of pursuing business activity. On the one hand, firms – by their nature – seek to maintain the efficiency and to gain a competitive advantage, on the other hand – they are more and more often obliged to balance environmental goals with economic goals. Although there are opinions that these goals are competitive in themselves, it is possible for firms to reconcile them effectively by adopting Environmental Sustainability Orientation. Since this orientation is analysed in the literature from various research perspectives, this paper attempts to conceptualise it from a Dynamic Capabilities perspective. Design/methodology/approach: The paper is theoretical and based on an in-depth review of the literature. The developed conceptual model includes the direct and indirect relations among dynamic capabilities formulated in multidimensional terms, Environmental Sustainability Orientation and organisational outcomes. Embedding considerations in resource-based theories, three key processes (organisational learning, integration and reconfiguration of resources) have also been analysed, which, as necessary for building dynamic capabilities, make it easier for firms to adopt strategic Environmental Sustainability Orientation. Findings: The considerations included in the paper complement the literature in the area of strategic management and make it easier to understand Environmental Sustainability Orientation at the organisational level. They also point to a need to undertake further scientific work, the authors of which can use the research propositions elaborated in the paper and thus empirically verify the proposed conceptual model. Originality/value: The key scientific contribution of the paper is the development of a research framework formulating Environmental Sustainability Orientation from a Dynamic Capabilities perspective, i.e., respectively: (1) the capability to identify opportunities and/or threats (sensing), (2) the capability to use these opportunities and/or cope with threats (seizing) and (3) the capability to reconfigure the firm’s resources and competences (reconfiguring). The logic of this approach results from the fact that the three fundamental processes underlying the building of dynamic capabilities – organisational learning, integration and reconfiguration of resources – supported by the conscious action of CEO, make it easier for firms to adopt strategic Environmental Sustainability Orientation [ABSTRACT FROM AUTHOR]

We implement a new stomatal conductance model, based on the optimality approach, within the Community Atmosphere Biosphere Land Exchange (CABLE) land surface model. Coupled land-atmosphere simulations are then performed using CABLE within the Australian Community Climate and Earth Systems Simulator (ACCESS) with prescribed sea surface temperatures. As in most land surface models, the default stomatal conductance scheme only accounts for differences in model parameters in relation to the photosynthetic pathway, but not in relation to plant functional types. The new scheme allows model parameters to vary by plant functional type, based on a global synthesis of observations of stomatal conductance under different climate regimes over a wide range of species. We show that the new scheme reduces the latent heat flux from the land surface over the boreal forests during the Northern Hemisphere summer by 0.5 to 1.0 mm day-1. This leads to warmer daily maximum and minimum temperatures by up to 1.0 °C and warmer extreme maximum temperatures by up to 1.5 °C. These changes generally improve the climate model's climatology and improve existing biases by 10-20 %. The change in the surface energy balance also affects net primary productivity and the terrestrial carbon balance. We conclude that the improvements in the global climate model which result from the new stomatal scheme, constrained by a global synthesis of experimental data, provide a valuable advance in the long-term development of the ACCESS modelling system. [ABSTRACT FROM AUTHOR]

The response of the global climate-carbon cycle system to an extremely large Northern Hemisphere mid latitude volcanic eruption is investigated using ensemble integrations with the comprehensive Earth System Model MPI-ESM. The model includes dynamical compartments of the atmosphere and ocean and interactive modules of the terrestrial biosphere as well as ocean biogeochemistry. The MPI-ESM was forced with anomalies of aerosol optical depth and effective radius of aerosol particles corresponding to a super eruption of the Yellowstone volcanic system. The model experiment consists of an ensemble of fifteen model integrations that are started at different pre-ENSO states of a contol experiment and run for 200 yr after the volcanic eruption. The climate response to the volcanic eruption is a maximum global monthly mean surface air temperature cooling of 3.8 K for the ensemble mean and from 3.3 K to 4.3 K for individual ensemble members. Atmospheric pCO2 decreases by a maximum of 5 ppm for the ensemble mean and by 3 ppm to 7 ppm for individual ensemble members approximately 6 yr after the eruption. The atmospheric carbon content only very slowly returns to near pre-eruption level at year 200 after the eruption. The ocean takes up carbon shortly after the eruption in response to the cooling, changed wind fields, and ice cover. This physics driven uptake is weakly counteracted by a reduction of the biological export production mainly in the tropical Pacific. The land vegetation pool shows a distinct loss of carbon in the initial years after the eruption which has not been present in simulations of smaller scale eruptions. The gain of the soil carbon pool determines the amplitude of the CO2 perturbation and the long term behaviour of the overall system: an initial gain caused by reduced soil respiration is followed by a rather slow return towards pre-eruption levels. During this phase, the ocean compensates partly for the reduced atmospheric carbon content in response to the land's gain. In summary, we find that the volcanic eruption has long lasting effects on the carbon cycle: after 200 yr, the ocean and the land carbon pools are still different from the pre-eruption state, and the land carbon pools (vegetation and soil) show some long lasting local anomalies that are only partly visible in the global signal. [ABSTRACT FROM AUTHOR]

Due to the proliferation of geophysical models, particularly climate models, the increasing resolution of their spatiotemporal estimates of Earth system processes, and the desire to easily share results with collaborators, there is a genuine need for tools to manage, aggregate, visualize, and share datasets. We present a new, web-based software tool – the Carbon Data Explorer – that provides these capabilities for gridded geophysical datasets. While originally developed for visualizing carbon flux, this tool can accommodate any time-varying, spatially explicit scientific dataset, particularly NASA Earth system science Level III products. In addition, the tool's open-source licensing and web presence facilitate distributed scientific visualization, comparison with other datasets and uncertainty estimates, and data publishing and distribution. [ABSTRACT FROM AUTHOR]

The oceanic crust is believed to host the largest potential habitat for microbial life on Earth, yet, next to nothing is known about this deep, concealed biosphere. Here fossilised fungal colonies in subseafloor basalts are reported from three different seamounts in the Pacific Ocean. The fungal colonies consist of various characteris- tic structures interpreted as fungal hyphae, fruit bodies and spores. The fungal hyphae are well preserved with morphological characteristics such as hyphal walls, septa, thallic conidiogenesis, and hyphal tips with hyphal vesicles within. The fruit bodies consist of large (∼50-200 µm in diameter) body-like structures with a defined outer membrane and an interior filled with calcite. The fruit bodies have at some stage been emptied of their contents of spores and filled by carbonate forming fluids. A few fruit bodies not filled by calcite and with spores still within support this interpretation. Spore-like structures (ranging from a few µm:s to ∼20 µm in diameter) are also observed outside of the fruit bodies and in some cases concentrated to openings in the membrane of the fruit bodies. The hyphae, fruit bodies and spores are all closely associated with a crust lining the vein walls that probably represent a mineralized biofilm. The results support a fungal presence in deep subseafloor basalts and indicate that such habitats were vital between ∼81 and 48 Ma, and probably still is. It is suggested that near future ocean drilling programs prioritize sampling of live species to better understand this concealed biosphere. [ABSTRACT FROM AUTHOR]

The terrestrial biosphere is currently a strong sink for anthropogenic CO2 emissions. Through the radiative properties of CO2 the strength of this sink has a direct influence on the radiative budget of the global climate system. The accurate assessment of this sink and its evolution under a changing climate is, hence, paramount for any efficient management strategies of the terrestrial carbon sink to avoid dangerous climate change. Unfortunately, simulations of carbon and water fluxes with terrestrial biosphere models exhibit large uncertainties. A considerable fraction of this uncertainty is reflecting uncertainty in the parameter values of the process formulations within the models. This paper describes the systematic calibration of the process parameters of a terrestrial biosphere model against two observational data streams: remotely sensed FAPAR provided by the MERIS sensor and in situ measurements of atmospheric CO2 provided by the GLOBALVIEW flask sampling network. We use the Carbon Cycle Data Assimilation System (CCDAS) to systematically calibrate some 70 parameters of the terrestrial biosphere model BETHY. The simultaneous assimilation of all observations provides parameter estimates and uncertainty ranges that are consistent with the observational information. In a subsequent step these parameter uncertainties are propagated through the model to uncertainty ranges for predicted carbon fluxes. We demonstrate the consistent assimilation for two different set-ups: first at site scale, where MERIS FAPAR observations at a range of sites are used as simultaneous constraints, and second at global scale, where the global MERIS FAPAR product and atmospheric CO2 are used simultaneously. On both scales the assimilation improves the match to independent observations. We quantify how MERIS data improve the accuracy of the current and future (net and gross) carbon flux estimates (within and beyond the assimilation period). We further demonstrate the use of an interactive mission benefit analysis tool built around CCDAS to support the design of future space missions. We find that, for long-term averages, the benefit of FAPAR data is most pronounced for hydrological quantities, and moderate for quantities related to carbon fluxes from ecosystems. The benefit for hydrological quantities is highest for semi-arid tropical or sub-tropical regions. Length of mission or sensor resolution is of minor importance. [ABSTRACT FROM AUTHOR]

Insects defoliate and kill plants in many ecosystems worldwide. The consequences of these natural processes on terrestrial ecology and nutrient cycling are well established, and their potential climatic effects resulting from modified land-atmosphere exchanges of carbon, energy, and water are increasingly being recognized. We developed a Marauding Insect Module (MIM) to quantify, in the Integrated BIosphere Simulator (IBIS), the consequences of insect activity on biogeochemical and biogeophysical fluxes, also accounting for the effects of altered vegetation dynamics. MIM can simulate damage from broadleaf defoliators, needleleaf defoliators, and bark beetles, with the resulting impacts being estimated by IBIS based on the new, insect-modified state of the vegetation. MIM further accounts for the physical presence and gradual fall of insect-killed dead standing trees. The design of MIM should facilitate the addition of other insect types besides the ones already included and could guide the development of similar modules for other process-based vegetation models. After describing IBIS-MIM, we illustrate the usefulness of the model by presenting results spanning daily to centennial timescales for vegetation dynamics and cycling of carbon, energy, and water following a simulated outbreak of the mountain pine beetle. We then show that these simulated impacts agree with many previous studies based on field measurements, satellite data, or modelling. MIM and similar tools should therefore be of great value in assessing the wide array of impacts resulting from insect-induced plant damage in the Earth system. [ABSTRACT FROM AUTHOR]

Including a terrestrial nitrogen (N) cycle in Earth system models has led to substantial attenuation of predicted biosphere-climate feedbacks. However, the magnitude of this attenuation remains uncertain. A particularly important, but highly uncertain process is biological nitrogen fixation (BNF), which is the largest natural input of N to land ecosystems globally. In order to quantify this uncertainty, and estimate likely effects on terrestrial biosphere dynamics, we applied six alternative formulations of BNF spanning the range of process formulations in current state-of-the-art biosphere models within a common framework, the O-CN model: a global map of static BNF rates, two empirical relationships between BNF and other ecosystem variables (net primary productivity (NPP) and evapotranspiration), two process-oriented formulations based on plant N status, and an optimality-based approach. We examined the resulting differences in model predictions under ambient and elevated atmospheric [CO2] and found that the predicted global BNF rates and their spatial distribution for contemporary conditions were broadly comparable, ranging from 95 to 134 Tg N yr-1 (median 119 Tg N yr-1), despite distinct regional patterns associated with the assumptions of each approach. Notwithstanding, model responses in BNF rates to elevated levels of atmospheric [CO2] (+200 ppm) ranged between -4 Tg N yr-1 (-3%) and 56 Tg N yr-1 (+42%) (median 7 Tg N yr-1 (+8%)). As a consequence, future projections of global ecosystem carbon storage (+281 to +353 Pg C, or +13 to +16%), as well as N2O emission (-1.6 to +0.5 Tg N yr-1, or -19 to +7%) differed significantly across the different model formulations. Our results emphasize the importance of better understanding the nature and magnitude of BNF responses to change-induced perturbations, particularly through new empirical perturbation experiments and improved model representation. [ABSTRACT FROM AUTHOR]

Assigning proper prior uncertainties for inverse modeling of CO2 is of high importance, both to regularize the otherwise ill-constrained inverse problem, and to quantitatively characterize the magnitude and structure of the error between prior and "true" flux. We use surface fluxes derived from three biosphere models VPRM, ORCHIDEE, and 5PM, and compare them against daily averaged fluxes from 53 Eddy Covariance sites across Europe for the year 2007, and against repeated aircraft flux measurements encompassing spatial transects. In addition we create synthetic observations to substitute observed by modeled fluxes to explore the potential to infer prior uncertainties from model-model residuals. To ensure the realism of the synthetic data analysis, a random measurement noise was added to the tower fluxes which were used as reference. The temporal autocorrelation time for tower model-data residuals was found to be around 35 days for both VPRM and ORCHIDEE, but significantly different for the 5PM model with 76 days. This difference is caused by a few sites with large model-data bias. The spatial correlation of the model-data residuals for all models was found to be very short, up to few tens of km. Long spatial correlation lengths up to several hundreds of km were determined when synthetic data were used. Results from repeated aircraft transects in south-western France, are consistent with those obtained from the tower sites in terms of spatial autocorrelation (35 km on average) while temporal autocorrelation is markedly lower (13 days). Our findings suggest that the different prior models have a common temporal error structure. Separating the analysis of the statistics for the model data residuals by seasons did not result in any significant differences of the spatial correlation lengths. [ABSTRACT FROM AUTHOR]

Priming of soil carbon decomposition encompasses different processes through which the decomposition of native (already present) soil organic matter is amplified through the addition of new organic matter, with new inputs typically being more labile than the native soil organic matter. Evidence for priming comes from laboratory and field experiments, but to date there is no estimate of its impact at global scale and under the current anthropogenic perturbation of the carbon cycle. Current soil carbon decomposition models do not include priming mechanisms, thereby introducing uncertainty when extrapolating short-term local observations to ecosystem and regional to global scale. In this study we present a simple conceptual model of decomposition priming, called PRIM, able to reproduce laboratory (incubation) and field (litter manipulation) priming experiments. Parameters for this model were first optimized against data from 20 soil incubation experiments using a Bayesian framework. The optimized parameter values were evaluated against another set of soil incubation data independent from the ones used for calibration and the PRIM model reproduced the soil incubations data better than the original, CENTURY-type soil decomposition model, whose decomposition equations are based only on first order kinetics. We then compared the PRIM model and the standard first order decay model incorporated into the global land biosphere model ORCHIDEE. A test of both models was performed at ecosystem scale using litter manipulation experiments from 5 sites. Although both versions were equally able to reproduce observed decay rates of litter, only ORCHIDEE-PRIM could simulate the observed priming (R² = 0.54) in cases where litter was added or removed. This result suggests that a conceptually simple and numerically tractable representation of priming adapted to global models is able to capture the sign and magnitude of the priming of litter and soil organic matter. [ABSTRACT FROM AUTHOR]

Rivers are the primary means by which sediments and carbon are transported from the terrestrial biosphere to the oceans but gaps remain in our understanding of carbon associations from source to sink. Bed sediments from the Sacramento-San Joaquin River Delta (CA) were fractionated according to density and analyzed for sediment mass distribution, elemental (C and N) composition, mineral surface area, and stable carbon and radiocarbon isotope compositions of organic carbon (OC) and fatty acids to evaluate the nature of organic carbon in river sediments. OC was unevenly distributed among density fractions. Mass and TOC were in general concentrated in mesodensity (1.6-2.0 and 2.0-2.5 g cm-3) fractions, comprising 84.0 ± 1.3% of total sediment mass and 80.8 ± 13.3% of total OC (TOC). Low density (< 1.6 g cm-3) material, although rich in OC (34.0 ± 2.0% OC) due to woody debris, constituted only 17.3 ± 12.8% of TOC. High density (> 2.5 g cm-3) organic-poor, mineral material made-up 13.7 ± 1.4% of sediment mass and 2.0 ± 0.9% of TOC. Stable carbon isotope compositions of sedimentary OC were relatively uniform across bulk and density fractions (δ13C -27.4 ± 0.5 ‰). Radiocarbon content varied from Δ14C values of -382 (radiocarbon age 3800 yr BP) to +94 ‰ (modern) indicating a~mix of young and pre-aged OC. Fatty acids were used to further constrain the origins of sedimentary OC. Short-chain n-C14-n-C18 fatty acids of algal origin were depleted in δ13C (δ13C -37.5 to -35.2 ‰) but were enriched in 14C (Δ14C > 0) compared to long-chain n-C24-n-C28 acids of vascular plant origins with higher δ13C (-33.0 to -31.0 ‰) but variable Δ14C values (-180 and 61 ‰). These data demonstrate the potentially complex source and age distributions found within river sediments and provide insights about sediment and organic matter supply to the Sacramento-San Joaquin River Delta. [ABSTRACT FROM AUTHOR]

Kirschbaum (Mitig Adapt Strat Glob Change 11:1151-1164, 2006) explores the climatic impact over time of temporarily sequestering carbon from the atmosphere. He concludes that temporary storage of carbon in the terrestrial biosphere ''achieves effectively no climate-change mitigation''. His strongly worded statement begs for a response. This paper argues that Kirschbaum's conclusion is an artifact of the specific perspective of his analysis and his choice of a definition for climate-change impact. Even temporary sinks put us on a lower path for climate change, a path that will not otherwise be accessible. For carbon sinks in the terrestrial biosphere, we argue that sooner is better and longer is better, but even known temporary sinks have value. [ABSTRACT FROM AUTHOR]

Background: The impact of climate change has led to variations in various biological processes, leading to altered transmission dynamics of infectious diseases, including snail-borne diseases (SBDs). Fascioliasis is one of the neglected zoonotic tropical snail-borne diseases caused by the trematode of the genus Fasciola. This review focused on laboratory experimental and model studies that evaluate the potential effect of temperature change on the ecology and biology of the intermediate host snails (IHS) of Fasciola. Methods: A literature search was conducted on Google Scholar, EBSCOhost, and PubMed databases using predefined medical subject heading terms, Boolean operators, and truncation symbols in combination with direct keywords: Fasciolosis AND Temperature, Lymnaea OR Austropeplea OR Radix OR Galba OR Fossaria OR Pseudosuccinea AND growth, fecundity, AND survival at the global scale. Other search terms used were (Fascioliasis AND Temperature), (Lymnaea AND Temperature), (Austropeplea AND Temperature), (Fossaria AND Temperature), (Galba AND Temperature), (Pseudosuccinea AND Temperature), and (Radix AND Temperature). Results: The final synthesis included thirty-five published articles. The studies reviewed indicated that temperature rise may alter the distribution, and optimal conditions for breeding, growth, and survival of IHS, ultimately resulting in changing the transmission dynamics of fascioliasis. The literature also confirmed that the life history traits of IHS and their interaction with the liver fluke parasites are driven by temperature, and hence climate change may have profound outcomes on the population size of snails, parasite density, and disease epidemiology. Conclusion: We concluded that understanding the impact of temperature on the growth, fecundity, and survival of IHS may broaden our knowledge of the possible effects of climate change and hence inform fascioliasis control programs. Author summary: Fascioliasis is a neglected tropical disease caused by flatworms or liver flukes of the genus Fasciola. The review paper focuses on the effect of temperature on the life history traits of intermediate hosts of fascioliasis. The authors aim to explore the impact of temperature on the growth, survival, and reproduction of the host snails and the development of parasites inside intermediate hosts. Fascioliasis is considered a major public health problem in many countries, affecting both humans and livestock. The disease is transmitted through the consumption of contaminated water or vegetation containing the infective stage of metacercaria. The review paper highlights that temperature plays a crucial role in the life history traits of these intermediate hosts. The authors gathered and analyzed various studies conducted on different intermediate host snails of Fasciola species to investigate the relationship between temperature and the development, survival, reproduction, and infectivity of the parasites within them. Their findings reveal that the temperature can significantly influence the life history traits of these intermediate hosts. Higher temperatures generally promote faster development, increased reproduction, and higher infectivity rates. However, there is a limit to the beneficial effects of temperature, beyond which the survival and fitness of the intermediate hosts start to decline. The authors also emphasize the relevance of understanding the impact of temperature on fascioliasis in the context of climate change. As global temperatures continue to rise, the distribution and prevalence of fascioliasis may change, affecting the transmission dynamics of the disease. This knowledge is crucial for the design and implementation of effective control strategies to mitigate the impact of fascioliasis on human and animal health. [ABSTRACT FROM AUTHOR]

Stomatal conductance (gs) affects the fluxes of carbon, energy and water between the vegetated land surface and the atmosphere. We test an implementation of an optimal stomatal conductance model within the Community Atmosphere Biosphere Land Exchange (CABLE) land surface model (LSM). In common with many LSMs, CABLE does not differentiate between gs model parameters in relation to plant functional type (PFT), but instead only in relation to photosynthetic pathway. We therefore constrained the key model parameter "g1" which represents a plants water use strategy by PFT based on a global synthesis of stomatal behaviour. As proof of concept, we also demonstrate that the g1 parameter can be estimated using two long-term average (1960-1990) bioclimatic variables: (i) temperature and (ii) an indirect estimate of annual plant water availability. The new stomatal models in conjunction with PFT parameterisations resulted in a large reduction in annual fluxes of transpiration (~ 30% compared to the standard CABLE simulations) across evergreen needleleaf, tundra and C4 grass regions. Differences in other regions of the globe were typically small. Model performance when compared to upscaled data products was not degraded, though the new stomatal conductance scheme did not noticeably change existing model-data biases. We conclude that optimisation theory can yield a simple and tractable approach to predicting stomatal conductance in LSMs. [ABSTRACT FROM AUTHOR]

The eastern tropical North Atlantic (ETNA) is characterized by a highly productive coastal upwelling system and a moderate oxygen minimum zone with lowest open ocean oxygen (O2) concentrations of around 40 µmol kg-1. Only recently, the discovery of re-occurring mesoscale eddies with sometimes close to anoxic O2 concentrations (< 1 µmol kg-1) and located just below the mixed layer challenged our understanding of O2 distribution and biogeochemical processes in this area. Here, we present the first metagenomic dataset from a deoxygenated anticyclonic modewater eddy in the open waters of the ETNA. In the eddy, we observed a significantly lower bacterial diversity compared to surrounding waters, along with a significant community shift. We detected enhanced primary productivity in the surface layer of the eddy indicated by elevated chlorophyll concentrations and increased carbon uptake rates up to three times as high as in surrounding waters. Carbon uptake below the euphotic zone correlated to the presence of a specific high-light ecotype of Prochlorococcus, which is usually underrepresented in the ETNA. Our combined data indicate that high primary production in the eddy fuels export production and the presence of a specific microbial community responsible for enhanced respiration at shallow depths, below the mixed layer base. Progressively decreasing O2 concentrations in the eddy were found to promote transcription of the key gene for denitrification, nirS, in the O2- depleted core waters. This process is usually absent from the open ETNA waters. In the light of future ocean deoxygenation our results show exemplarily that even distinct events of anoxia have the potential to alter microbial community structures and with that critically impact primary productivity and biogeochemical processes of oceanic water bodies. [ABSTRACT FROM AUTHOR]

From basic physical assumptions we derive a simple linear model of the global CO2 cycle without free parameters. It yields excellent agreement with the observations reported by the carbon dioxide information analysis center (CDIAC) as time series of atmospheric CO2 growth, of sinks in the ocean and of absorption by the biosphere. The agreement extends from the year 1850 until present (2013). Based on anthropogenic CO2 emission scenarios until 2150, future atmospheric CO2 concentrations are calculated. As the model shows, and depending on the emission scenario, the airborne fraction of CO2 begins to decrease in the year ~ 2050 and becomes negative at the latest in ~ 2130. At the same time the concentration of the atmospheric CO2 will reach a maximum between ~ 500 and ~ 900 ppm. As a consequence, increasing anthropogenic CO2 emissions will make the ocean and the biosphere the main reservoirs of anthropogenic CO2 in the long run. Latest in about 150 years, anthropogenic CO2 emission will no longer increase the CO2 content of the atmosphere. [ABSTRACT FROM AUTHOR]

Generic land surface models are generally driven by large-scale forcing datasets to describe the climate, the surface characteristics (soil texture, vegetation dynamic) and the cropland management (irrigation). This paper investigates the errors in these forcing variables and their impacts on the evapotranspiration (ET) simulated from the Interactions between Soil, Biosphere, and Atmosphere (ISBA-A-gs) land surface model over a 12 year Mediterranean crop succession. We evaluate the forcing datasets used in the standard implementation of ISBA over France where the model is driven by the SAFRAN high spatial resolution atmospheric reanalysis, the Leaf Area Index (LAI) cycles derived from the Ecoclimap-II land surface parameter database and the soil texture derived from the French soil database. For climate, we focus on the radiations and rainfall variables and we test additional datasets which includes the ERA-Interim low spatial resolution reanalysis, the Global Precipitation Climatology Centre dataset (GPCC) and the MeteoSat Second Generation (MSG) satellite estimate of downwelling shortwave radiations. The methodology consists in comparing the simulation achieved using large-scale forcing datasets with the simulation achieved using local observations for each forcing variable. The relative impacts of the forcing variables on simulated ET are compared with each other and with the model uncertainties triggered by errors in soil parameters. LAI and the lack of irrigation in the simulation generate the largest mean deviations in ET between the large-scale and the local-scale simulations (equivalent to 24 and 19 months of ET over 12 yr). The climate induces smaller mean deviations equivalent to 7-8 months of ET over 12 yr. The soil texture has the lowest impact (equivalent to 3 months of ET). However, the impact of errors in the forcing variables is smaller than the impact triggered by errors in the soil parameters (equivalent to 27 months of ET). The absence of irrigation which represents 18% of cumulative rainfall over 12 years induces a deficit in ET of 14 %. It generates much larger variations in incoming water for the model than the differences in rainfall between the reanalysis datasets. ET simulated with the Ecoclimap-II LAI climatology is overestimated by 18% over 12 years. This is related to the overestimation of the mean LAI over the crop cycle which reveals inaccurate representation of Mediterranean crop cycles. Compared to SAFRAN, the use of the ERA-I reanalysis, the GPCC rainfall and the downwelling shortwave radiation derived from the MSG satellite have little influence on the ET simulation performances. The error in yearly ET is mainly driven by the error in yearly rainfall and to a less extent by radiations. The SAFRAN and MSG satellite shortwave radiation estimates show similar negative biases (-9 and -11 Wm-2). The ERA-I bias in shortwave radiations is 4 times smaller at daily time scale. Both SAFRAN and ERA-I underestimate longwave downwelling radiations by -12 and -16 Wm-2, respectively. The biases in shortwave and longwave radiations show larger inter-annual variation for SAFRAN than for ERA-I. Regarding rainfall, SAFRAN and ERA-I/GPCC are slightly biased at daily and longer time scales (1 and 0.5% of the mean rainfall measurement). The SAFRAN rainfall estimates are more precise due to the use of the in situ daily rainfall measurements of the Avignon site in the reanalysis. [ABSTRACT FROM AUTHOR]

In this present study the ability of the SimSphere Soil Vegetation Atmosphere Transfer (SVAT) model in estimating key parameters characterising land surface interactions was evaluated. Specifically, SimSphere's performance in predicting Net Radiation (Rnet), Latent Heat (LE), Sensible Heat (H) and Air Temperature (Tair) at 1.3 and 50m was examined. Model simulations were validated by ground-based measurements of the corresponding parameters for a total of 70 days of the year 2011 from 7 CarboEurope network sites. These included a variety of biomes, environmental and climatic conditions in the models evaluation. Overall, model performance can largely be described as satisfactory for most of the experimental sites and evaluated parameters. For all model parameters compared, predicted H fluxes consistently obtained the highest agreement to the in-situ data in all ecosystems, with an average RMSD of 55.36Wm-2. LE fluxes and Rnet also agreed well with the in-situ data with RSMDs of 62.75 and 64.65Wm-2 respectively. A good agreement between modelled and measured LE and H fluxes was found, especially for smoothed daily flux trends. For both Tair 1.3m and Tair 50m a mean RMSD of 4.14 and 3.54 °C was reported respectively. This work presents the first all-inclusive evaluation of SimSphere, particularly so in a European setting. Results of this study contribute decisively towards obtaining a bet ter understanding of the model's structure and its correspondence to the real world system. Findings also further establish the model's capability as a useful teaching and research tool in modelling Earth's land surface interactions. This is of considerable importance in the light of the rapidly expanding use of the model worldwide, including ongoing research by various Space Agencies examining its synergistic use with Earth Observation data towards the development of operational products at a global scale. [ABSTRACT FROM AUTHOR]

The continuous in-situ measurement of δ18O in atmospheric CO2 opens a new door to differentiating between CO2 source and sink components with high temporal resolution. Continuous 13C-CO2 measurement systems have been commercially available already for some time, but until now, only few instruments have been able to provide a continuous measurement of the oxygen isotope ratio in CO2. Besides precise 13C/12C observations, the Fourier Transform InfraRed (FTIR) spectrometer also measures the 18O/16O ratio of CO2, but the precision and accuracy of the measurements has not been evaluated yet. Here we present a first analysis of δ18O-CO2 (and δ13C CO2) measurements with the FTIR in Heidelberg. We find that our spectrometer measures 18O in CO2 with a reproducibility of better than 0.3‰ at a temporal resolution of less than 10 min, as determined from surveillance gas measurements over a period of ten months. An Allan deviation test shows that the δ18O repeatability reaches 0.15‰ for half-hourly means. The compatibility of our spectroscopic measurements was determined by comparing FTIR measurements of calibration gases and ambient air to mass-spectrometric measurements of flask samples, filled with the cylinder gases or episodically collected over a diurnal cycle (event). We found that direct cylinder gas measurements agree to 0.01±0.04‰ (mean and standard deviation) for δ13C-CO2 and 0.01±0.11‰ for δ18O. Two weekly episodes of recent ambient air measurements, one in winter and one in summer, are discussed in view of the question, which potential insights and new challenges combined highly resolved δ18O-CO2 and δ13C-CO2 records may provide in terms of better understanding regional scale continental carbon exchange processes [ABSTRACT FROM AUTHOR]

Today's biodiversity crisis fundamentally threatens the habitability of the planet, thus ranking among the primary human challenges of our time. Much emphasis is currently placed on the loss of biodiversity in the Anthropocene, yet these debates often portray biodiversity as a purely natural phenomenon without much consideration of its human dimensions and frequently lack long-term vistas. This paper offers a deep-time perspective on the key role of the evolving human niche in ecosystem functioning and biodiversity dynamics. We summarize research on past hunter–gatherer ecosystem contributions and argue that human–environment feedback systems with important biodiversity consequences are probably a recurrent feature of the Late Pleistocene, perhaps with even deeper roots. We update current understandings of the human niche in this light and suggest that the formation of palaeo-synanthropic niches in other animals proffers a powerful model system to investigate recursive interactions of foragers and ecosystems. Archaeology holds important knowledge here and shows that ecosystem contributions vary greatly in relation to different human lifeways, some of which are lost today. We therefore recommend paying more attention to the intricate relationship between biodiversity and cultural diversity, contending that promotion of the former depends on fostering the latter. This article is part of the theme issue 'Ecological novelty and planetary stewardship: biodiversity dynamics in a transforming biosphere'. [ABSTRACT FROM AUTHOR]

In the Anthropocene, intensifying ecological disturbances pose significant challenges to our predictive capabilities for ecosystem responses. Macroecology—which focuses on emergent statistical patterns in ecological systems—unveils consistent regularities in the organization of biodiversity and ecosystems. These regularities appear in terms of abundance, body size, geographical range, species interaction networks, or the flux of matter and energy. This paper argues for moving beyond qualitative resilience metaphors, such as the 'ball and cup', towards a more quantitative macroecological framework. We suggest a conceptual and theoretical basis for ecological resilience that integrates macroecology with a stochastic diffusion approximation constrained by principles of biological symmetry. This approach provides an alternative novel framework for studying ecological resilience in the Anthropocene. We demonstrate how our framework can effectively quantify the impacts of major disturbances and their extensive ecological ramifications. We further show how biological scaling insights can help quantify the consequences of major disturbances, emphasizing their cascading ecological impacts. The nature of these impacts prompts a re-evaluation of our understanding of resilience. Emphasis on regularities of ecological assemblages can help illuminate resilience dynamics and offer a novel basis to predict and manage the impacts of disturbance in the Anthropocene more efficiently. This article is part of the theme issue 'Ecological novelty and planetary stewardship: biodiversity dynamics in a transforming biosphere'. [ABSTRACT FROM AUTHOR]

It is well known that aboveground productivity usually increases with precipitation. However, how belowground carbon (C) processes respond to changes in precipitation remains elusive, although belowground net primary productivity (BNPP) represents more than one-half of NPP and soil stores the largest terrestrial C in the biosphere. This paper reviews the patterns of belowground C processes (BNPP and soil C) in response to changes in precipitation from transect studies, manipulative experiments, modeling and data integration and synthesis. The results suggest the possible existence of nonlinear patterns of BNPP and soil C in response to changes in precipitation, which is largely different from linear response for aboveground productivity. C allocation, root turnover time and species composition may be three key processes underlying mechanisms of the nonlinear responses to changes in precipitation for belowground C processes. In addition, microbial community structure and long-term ecosystem processes (e.g. mineral assemblage, soil texture, aggregate stability) may also affect patterns of belowground C processes in response to changes in precipitation. At last, we discuss implications and future perspectives for potential nonlinear responses of belowground C processes to changes in precipitation. [ABSTRACT FROM AUTHOR]

Understanding and simulating land biosphere processes happening at the interface between plants and atmosphere are important research activities with operational applications for monitoring and predicting seasonal and inter-annual variability of terrestrial carbon fluxes in connection to a changing climate. This paper reports a comparison between three different Land Surface Models (LSMs), ORCHIDEE, ISBA-A-gs and CTES- SEL used in the Copernicus-Land project precursor, forced with the same meteorological data, and compared with the carbon fluxes measured at 32 Eddy Covariance (EC) flux tower sites in Europe. The results show that the three models have the best performance for forest sites and the poorest performance for cropland and grassland sites. In addition, the three models have difficulties capturing the seasonality of Mediterranean and Sub-tropical biomes, characterized by dry summers. This reduced simulation performance is also reflected in deficiencies in diagnosed Light Use Efficiency (LUE) and Vapour Pressure Deficit (VPD) dependencies compared to observations. Shortcomings in the forcing data may also play a role. These results indicate that more research is needed on the LUE and VPD functions for Mediterranean and Sub-tropical biomes. Finally, this study highlights the importance well representing phenology (i.e. Leaf Area evolution) and management (i.e. rotation/irrigation for cropland, and grazing/harvesting for grassland) to simulate the carbon dynamics of European ecosystems and the importance of ecosystem level observation in models development and validation. [ABSTRACT FROM AUTHOR]

Soil organic matter (SOM) is the largest store of organic carbon (C) in the biosphere, but still the turnover of SOM is incompletely understood and not well described in global C cycle models. Here we use the Community Land Model (CLM) and compare the out- put for soil organic C (SOC) to estimates from a global data set. We also modify the assumptions about SOM turnover in two ways: (1) we assume distinct temperature sensitivities of SOC pools with different turnover time and (2) we assume a priming effect, such that decomposition rate of native SOM increases in response to a supply of fresh organic matter. The standard model predicted the global distribution of SOM reasonably well in most areas, but it failed to predict the very high stocks of SOM at high latitudes. It also predicted somewhat too much SOC in areas with high plant productivity, such as tropical rain forests and some mid-latitude areas. Assuming that the temperature sensitivity of SOC decomposition is dependent on the turnover rate of component pools reduced total SOC at equilibrium by a relatively small amount (<1% globally). Including a priming effect reduced total global SOC more (6.6% globally) and tended to decrease SOC most in areas with high plant input (tropical and temperate forests), which were also the areas where the unmodified model overpredicted SOC (by about 40 %). The model was then run with climate change prediction for the standard and modified versions. Future simulations showed that differences between the standard and modified versions were maintained in a future with climate change (4-6 and 23-47 Pg difference in soil carbon between standard simulation and the modified with temperature sensitivity and priming respectively). [ABSTRACT FROM AUTHOR]

The Weather Research & Forecasting meteorological (WRF) model has been coupled to the Soil Plant Atmosphere (SPA) terrestrial ecosystem model, to produce WRF-SPA. SPA generates realistic land-atmosphere exchanges through fully coupled hydrologi- cal, carbon and energy cycles. The addition of a land surface model (SPA) capable of modelling biospheric CO2 exchange allows WRF-SPA to be used for investigating the feedbacks between biosphere carbon balance, meteorology and land management/ land use change. We have extensively validated WRF-SPA using multi-annual observations of air temperature, turbulent fluxes, net radiation and net ecosystem ex change of CO2 at three sites, representing the dominant vegetation types in Scotland (forest, managed grassland and arable agriculture). WRF-SPA generates more realistic seasonal behaviour at the site level compared to an unmodified version of WRF, and produces realistic CO2 exchanges. WRF-SPA is also able to realistically model atmospheric profiles of CO2 over Scotland, spanning a 3 yr period (2004-2006), capturing both profile structure, indicating realistic transport, and magnitude indicating appropriate source sink distribution and CO2 exchange. WRF-SPA makes use of CO2 tracer pools and can therefore identify and quantify land surface contributions to the modelled atmospheric CO2 signal at a specified location. [ABSTRACT FROM AUTHOR]

Numerous reactive volatile organic compounds (VOCs) are emitted into the atmosphere by vegetation. Most biogenic VOCs are highly reactive towards the atmosphere's most important oxidant, the hydroxyl (OH) radical. One way to investigate the chemical interplay between biosphere and atmosphere is through the measurement of total OH reactivity, the total loss rate of OH radicals. This study presents the first determination of total OH reactivity emission rates (measurements via the Comparative Reactivity Method) based on a branch cuvette enclosure system mounted on a Norway spruce (Picea abies) throughout spring, summer and autumn 2011. In parallel separate VOC emission rates were monitored by a Proton Transfer Reaction-Mass Spectrometer (PTR-MS), and total ozone (O3) loss rates were obtained inside the cuvette. Total OH reactivity emission rates were in general temperature and light dependent, showing strong diel cycles with highest values during daytime. Monoterpene emissions contributed most, accounting for 56-69% of the measured total OH reactivity flux in spring and early summer. However, during late summer and autumn the monoterpene contribution decreased to 11-16%. At this time, a large missing fraction of the total OH reactivity emission rate (70-84%) was found when compared to the VOC budget measured by PTR-MS. Total OH reactivity and missing total OH reactivity emission rates reached maximum values in late summer corresponding to the period of highest temperature. Total O3 loss rates within the closed cuvette showed similar diel profiles and comparable seasonality to the total OH reactivity fluxes. Total OH reactivity fluxes were also compared to emissions from needle storage pools predicted by a temperature-only dependent algorithm. Deviations of total OH reactivity fluxes from the temperature-only dependent emission algorithm were observed for occasions of mechanical and heat stress. While for mechanical stress, induced by strong wind, measured VOCs could explain total OH reactivity emissions, during heat stress they could not. The temperature driven algorithm matched the diel course much better in spring than in summer, indicating a different production and emission scheme for summer and early autumn. During these times, unmeasured and possibly unknown primary biogenic emissions contributed significantly to the observed total OH reactivity flux. [ABSTRACT FROM AUTHOR]

Methane plays an important role as a radiatively and chemically active gas in our atmosphere. Until recently, sources of atmospheric methane in the biosphere have been attributed to strictly anaerobic microbial processes during degradation of organic matter. However, a large fraction of methane produced in the anoxic soil layers does not reach the atmosphere due to methanotrophic consumption in the overlaying oxic soil. Although methane fluxes from aerobic soils have been observed an alternative source other than methanogenesis has not been identified thus far. Here we provide evidence for non-microbial methane formation in soils under oxic conditions. We found that soils release methane upon heating and other environmental actors like ultraviolet irradiation, and drying-rewetting cycles. We suggest that chemical formation of methane during degradation of soil organic matter may represent the missing soil source that is needed to fully understand the complete methane cycle within the pedosphere. Although the emission fluxes are relatively low when compared to those from wetlands, they may be important in warm and wet regions subjected to ltraviolet radiation. We suggest that this methane source is highly sensitive to global change. [ABSTRACT FROM AUTHOR]

The article presents a study that determines the effect of the structural error of biosphere models when used in assimilating net ecosystem exchange (NEE) measurements to optimize uncertain model parameters within carbon cycle data assimilation 5 systems (CCDASs). It describes the method of the research that observes data from the model-minus-observation mismatch statistics. It notes the result of the study, which confirms the inferred characteristics of the model.

The (net) exchange of reactive nitrogen (Nr) with the atmosphere is an important driver for ecosystem productivity and greenhouse gas exchange. The exchange of airborne Nr includes various trace compounds that usually require different specific measurement techniques, and up to now fast response instruments suitable for eddy covariance measurements are only available for few of these compounds. Here we present eddy covariance flux measurements with a recently introduced converter (TRANC) for the sum of all Nr compounds (σNr). Measurements were performed over a managed grassland field with phases of net emission and net deposition of σNr and alternating dominance of oxidized (NOx) and reduced species (NH3). Spectral analysis of the eddy covariance data exhibited the existence of covariance function peaks at a reasonable time lag related to the sampling tube residence time under stationary conditions. Using ogive analysis, the high-frequency damping was quantified to 19-26 % for a low measurement height of 1.2 m and to about 10 % for 4.8 m measurement height. ΣNr concentrations and fluxes were compared to parallel NO and NO2 measurements by dynamic chambers and NH3 measurements by the aerodynamic gradient technique. The average concentration results indicate that close-to-full conversion of the main compounds NO2 and NH3 was generally obtained by the TRANC system. With an optimised sample inlet also the fluxes of these compounds were recovered fairly including net deposition and net emission phases. The study shows that the TRANC system is suitable for fast response measurements of oxidized and reduced nitrogen compounds and can be used for continuous eddy covariance flux measurements of total reactive nitrogen. [ABSTRACT FROM AUTHOR]

Biosphere-atmosphere interactions play a critical role in governing atmospheric composition, mediating the concentration of key species such as ozone and aerosol, thereby influencing air quality and climate. The exchange of reactive trace gases and their oxidation products (both gas and particle phase) is of particular importance in this process. The FORCAsT (FORest Canopy AtmoSphere Transfer) one-dimensional model is developed to study the emission, deposition, chemistry and transport of volatile organic compounds (VOCs) and their oxidation products in the atmosphere within and above the forest canopy. We include an equilibrium partitioning scheme, making FORCAsT one of the few canopy models currently capable of simulating the formation of secondary organic aerosols (SOA) from VOC oxidation in a forest environment. We evaluate the capability of FORCAsT to reproduce observed concentrations of key gas-phase species and report modeled SOA concentrations within and above a mixed forest at the University of Michigan Biological Station (UMBS) during the Community Atmosphere-Biosphere Interactions Experiment (CABINEX) field campaign in summer 2009. We examine the impact of two different gas-phase chemical mechanisms on modelled concentrations of short-lived primary emissions, such as isoprene and monoterpenes, and their oxidation products. While the two chemistry schemes perform similarly under high-NOx conditions, they diverge at the low levels of NOx at UMBS. We identify peroxy radical and alkyl nitrate chemistry as the key causes of the differences, highlighting the importance of this chemistry in understanding the fate of biogenic VOCs (bVOCs) for both the modelling and measurement communities. [ABSTRACT FROM AUTHOR]

The bacterial and archaeal community composition and the possible carbon assimilation processes and energy sources of microbial communities in oligotrophic, deep, crystalline bedrock fractures is yet to be resolved. In this study, intrinsic microbial communities from six fracture zones from 180-2300 m depths in Outokumpu bedrock were characterized using high-throughput amplicon sequencing and metagenomic prediction. Comamonadaceae-, Anaerobrancaceae- and Pseudomonadaceae-related OTUs form the core community in deep crystalline bedrock fractures in Outokumpu. Archaeal communities were mainly composed of Methanobacteraceae-affiliating OTUs. The predicted bacterial metagenomes showed that pathways involved in fatty acid and amino sugar metabolism were common. In addition, relative abundance of genes coding the enzymes of autotrophic carbon fixation pathways in predicted metagenomes was low. This indicates that heterotrophic carbon assimilation is more important for microbial communities of the fracture zones. Network analysis based on co-occurrence of OTUs revealed the keystone genera of the microbial communities belonging to Burkholderiales and Clostridiales. Bacterial communities in fractures resemble those found from oligotrophic, hydrogen-enriched environments. Serpentinization reactions of ophiolitic rocks in Outokumpu assemblage may provide a source of energy and organic carbon compounds for the microbial communities in the fractures. Sulfate reducers and methanogens form a minority of the total microbial communities, but OTUs forming these minor groups are similar to those found from other deep Precambrian terrestrial bedrock environments. [ABSTRACT FROM AUTHOR]

Terrestrial ecosystem models can provide major insights into the responses of Earth's ecosystems to environmental changes and rising levels of atmospheric CO2. To achieve this goal, biosphere models need mechanistic formulations of the processes that drive the ecosystem functioning from diurnal to decadal time-scales. However, the subsequent complexity of model equations is associated with unknown or poorly calibrated parameters that limit the accuracy of long-term simulations of carbon or water fluxes and their inter-annual variations. In this study, we develop a data assimilation framework to constrain the parameters of a mechanistic land surface model (ORCHIDEE) with eddy-covariance observations of CO2 and latent heat fluxes made during the years 2001-2004 on the temperate beech forest site of Hesse, in eastern France. As a first technical issue, we show that for a complex process-based model such as ORCHIDEE with many (28) parameters to be retrieved, a Monte Carlo approach (genetic algorithm, GA) provides more reliable optimal parameter values than a gradient-based minimization algorithm (variational scheme). The GA allows finding the global minimum more efficiently whilst the variational scheme often provides values relative to local minima. The ORCHIDEE model is then optimized for each year, and for the whole 2001-2004 period. We first find that a reduced (< 10) set of parameters can be tightly constrained by the eddy-covariance observations with a typical error reduction of 90 %. We then show that including contrasted weather regimes (dry in 2003 and wet in 2002) is necessary to optimize few specific parameters (like the temperature dependence of the photosynthetic activity). Furthermore, we find that parameters inverted from four years of flux measurements are successful at enhancing the model fit to the data at several time-scales (from monthly to interannual) resulting to a typical modeling efficiency of 92% over the 2001-2004 period (Nash-Sutcliffe coefficient). This suggests that ORCHIDEE is able to robustly predict the fluxes of CO2 and latent heat of a temperate beech forest after optimisation. Finally, it is shown that using only one year of data does not produce robust enough optimized parameter sets in order to simulate properly the year-to-year flux variability. This emphasizes the need to assimilate data over several years, including contrasted weather regimes, to improve the simulated flux inter-annual variability. [ABSTRACT FROM AUTHOR]