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Recent studies suggest that climate change will lead to the local extinction of many tree species from large areas during this century, affecting the functioning and ecosystem services of many forests. This study reports on projected carbon losses due to the assumed local climate change-driven extinction of European beech (Fagus sylvatica L.) from Zala County, South-Western Hungary, where the species grows at the xeric limit of its distribution. The losses were calculated as a difference between carbon stocks in climate change scenarios assuming an exponentially increasing forest decline over time, and those in a baseline scenario assuming no climate change. In the climate change scenarios, three different sets of forest management adaptation measures were studied: (1) only harvesting damaged stands, (2) additionally salvaging dead trees that died due to climate change, and (3) replacing, at an increasing rate over time, beech with sessile oak (Quercus petraea Matt. Lieb.) after final harvest. Projections were made using the open access carbon accounting model CASMOFOR based on modeling or assuming effects of climate change on mortality, tree growth, root-to-shoot ratio and decomposition rates. Results demonstrate that, if beech disappears from the region as projected by the end of the century, over 80% of above-ground biomass carbon, and over 60% of the carbon stocks of all pools (excluding soils) of the forests will be lost by 2100. Such emission rates on large areas may have a discernible positive feedback on climate change, and can only partially be offset by the forest management adaptation measures.

Recent concepts of environmental sustainability have focused on narrative economic and societal aspects rather than quantitative ones. Many key sustainability indicators also lack a consistent definition of sustainability, have perspectives that are too short-term, and are unable to model the dynamics of complex environmental utilization which can then result in inappropriate projection of long-term sustainability and/or sustainability indication. Here I propose a generalized quantitative framework of environmental sustainability requiring that (1) environmental capacities and utilization rates are identified, (2) their complex temporal dynamics are quantitatively modeled or estimated (3) while also adjusting for uncertainties, and finally, (4) using one of three options, determining which cumulative utilization pathways can be sustained for a (usually well-defined) period of time. Using the example of wood volume and its growth as capacities and harvest as utilization, and the example of global greenhouse gas emissions as the utilization component and the capacity of the air to absorb these emissions, I demonstrate how the proposed framework can be applied in practice, how sustainability indicators could be developed, and also how they can inform policies and measures to ensure sustainability.

This article reports experiences gathered in 12 developing countries in Latin America and Africa with capacity development for national GHG inventory systems. The national systems and their ability to deliver on measurement, reporting and verification (MRV) requirements is assessed using a scorecard that covers the transparency, accuracy, completeness, consistency, and comparability of the GHG inventory as well as its institutional set-up and management aspects. The analysis shows that a quantitative assessment of GHG inventory systems with a scorecard is feasible and useful, and could commonly be used for tracking progress in MRV capacity development.Policy relevanceA large number of capacity development initiatives are underway to advance national GHG inventory systems in developing countries, particularly in the land-use sector. These aim to promote the reliable MRV of GHG emissions and removals, which is expected to underpin developing countries’ contributions to global mitigation efforts, including t...

Climate change particularly threatens the xeric limits of temperate-continental forests. In Hungary, annual temperatures have increased by 1.2 °C–1.8 °C in the last 30 years and the frequency of extreme droughts has grown. With the aim to gain stand-level prospects of sustainability, we have used local forest site variables to identify and project effects of recent and expected changes of climate. We have used a climatic descriptor (FAI index) to compare trends estimated from forest datasets with climatological projections; this is likely for the first time such a comparison has been made. Four independent approaches confirmed the near-linear decline of growth and vitality with increasing hot droughts in summer, using sessile oak as model species. The correlation between droughts and the expansion of pest and disease damages was also found to be significant. Projections of expected changes of main site factors predict a dramatic rise of future drought frequency and, consequently, a substantial shift of forest climate classes, especially at low elevation. Excess water-dependent lowland forests may lose supply from groundwater, which may change vegetation cover and soil development processes. The overall change of site conditions not only causes economic losses, but also challenges long-term sustainability of forest cover at the xeric limits.

This paper analyses the recent recurring dieback and growth decline of Black pine (P. nigra Arn. var austriaca) in the Keszthely mountains of south-west Hungary, and their relations to water deficits due to droughts. These relations were studied in five stands with low soil water storage capacity for the period 1981&ndash, 2016. The vitality was assessed using 60 tree-ring samples and changes in remotely sensed vegetation activity indices, i.e., the normalized difference vegetation index (NDVI) and the normalized difference infrared index (NDII). Water deficit was estimated by using meteorological drought indices such the standardized precipitation&ndash, evapotranspiration index (SPEI) and the forestry aridity index (FAI), as well as the relative extractable water (REW), calculated by the Brook90 hydrological model. Results revealed a strong dependency of annual tree ring width on the amount of water deficit as measured by all the above estimators, with the highest correlation shown by the summer REW. Droughts also showed a long-term superimposed effect on tree growth. NDII seemed to be more sensitive to drought conditions than NDVI. The robust dependency of tree growth on the summer water availability combined with the projected increasing aridity might lead to decreasing growth of Black pine in Hungary towards the end of the century. We thus argue that the suggestion by several papers that Black pine can be a possible substitute species in the Alpine and Mediterranean region in the future should be revisited.

We present the first comprehensive overview about the state-of-the-art estimates of the Hungarian biospheric greenhouse gas (GHG) balance. Biogeochemical models, statistical time series, and literature data are used together to describe grassland, forest, and arable land specific GHG fluxes. The estimates are aggregated to the country level to approximate the net biospheric greenhouse gas balance for the first time. The results suggest that the overall biospheric GHG balance of Hungary is negative (−13.8 Mt CO2-equivalent year-1), which means net GHG release to the atmosphere. According to this finding, the biosphere does not mitigate anthropogenic GHG emission in the country. More research is needed to constrain the estimates, and to provide reliable uncertainty estimates to the fluxes and stocks. We try to point out important research priorities that can help us to ­better understand the biogeochemical processes of the biosphere in Hungary, and to provide mitigation opportunities for biospheric GHG emission.

International audience; This paper is the outcome of a group discussion held at the Savonlinna meeting Management of forest ecosystems and its impact on the GHG budget'. The aim of this break-out group discussion was to Characterize forest management impacts on the GHG budget of forest ecosystems in different European regions'. In this paper we briefly characterize different options that a forest owner has in order to maintain or maximize forest carbon pools and carbon sequestration. These hectare scale descriptions of measures are then regarded in connection to the current state of European forests and how they can be combined with ongoing management trends and local issues. We point out the various possibilities that exist in European forests, where they are located, and where they could possibly be combined with adaptation. We identify these hotspots for largest growing stocks, largest peat areas, and, e.g. largest risks for loss of carbon due to fire or urban sprawl. We conclude that one common strategy cannot be designed. Within each region, local solutions have to be found that optimize goals and aim at integrated and sustainable land use.