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International agreements require countries to annually report on greenhouse gas emissions and removals. For the land-use sector, this includes estimating stock changes in various carbon pools. For carbon pools like mineral forest soil where a country-level statistical inventory based on measurements is very difficult, models are usually applied together with data from case studies. In this paper, we present a country-specific model together with case studies that aim at capturing major soil processes due to forestry activity. These processes include “hot moments”, e.g., disturbances that occur rarely but might result in relatively high emissions. The model only aims at developing a conservative estimate, rather than a central one, of net country-level carbon stock change with emissions overestimated and removals underestimated. The model is partially parameterised using paired sampling of soil organic carbon in the uppermost 30-cm layer, applying standard methods including those suggested by IPCC, in afforestations on former croplands and in artificial regenerations. Results show that soils of afforested croplands act as a sink, and carbon stock after regeneration might decrease due to disturbance by forest operations, but might also increase due to transfer of carbon from dead roots to soil depending on disturbance levels. The estimation at the country level, which involves additional considerations and data from the literature, suggests that overall, forest soils are a net sink in Hungary, but also that artificially limiting soil organic carbon changes estimation to the uppermost 30-cm layer as applied in the IPCC methodology might lead to artefacts.

Little information is available about the toxicity of inorganic selenium forms in soil animals. Therefore, the effects of selenate and selenite on the mortality and reproduction of Enchytraeus albidus were examined in standard laboratory tests with chronic exposure. Total and available amount of selenate and selenite were tested in a calcareous loamy chernozem soil. The LC(50) of selenate was 5.69 (2.7-8.12) mg kg(-1) dry wt. for total Se and 4.74 (2.14-6.98) mg kg(-1) dry wt. for available Se. Selenite LC(50) was as high as 22.5 (19.6-25.7) mg kg(-1) dry wt. for total Se and 8.10 (6.8-9.6) mg kg(-1) dry wt. for available Se. The EC(50) of selenate was 0.41 (0.35-0.48) mg kg(-1) dry wt. for total Se and 0.28 (0.24-0.34) mg kg(-1) dry wt. for available Se. Selenite EC(50) was as high as 7.3 (6.2-8.5) mg kg(-1) dry wt. for total Se and 2.46 (2.05-2.91) mg kg(-1) dry wt. for available Se. The response in reproduction was more sensitive to Se toxicity than the response in mortality. Selenate proved to be more toxic than selenite. Available data show that E. albidus may function as a biological indicator for some inorganic selenium forms in the soil.

Forest biomass and its change over time have been measured at both local and large scales, an example for the latter being forest greenhouse gas inventories. Currently used methodologies to obtain stock change estimates for large forest areas are mostly based on forest inventory information as well as various factors, referred to as biomass factors, or biomass equations, which transform diameter, height or volume data into biomass estimates. However, while forest inventories usually apply statistically sound sampling and can provide representative estimates for large forest areas, the biomass factors or equations used are, in most cases, not representative, because they are based on local studies. Moreover, their application is controversial due to the inconsistent or inappropriate use of definitions involved. There is no standardized terminology of the various factors, and the use of terms and definitions is often confusing. The present contribution aims at systematically summarizing the main types of biomass factors (BF) and biomass equations (BE) and providing guidance on how to proceed when selecting, developing and applying proper factors or equations to be used in forest biomass estimation. The contribution builds on the guidance given by the IPCC (Good practice guidance for land use, land-use change and forestry, 2003) and suggests that proper application and reporting of biomass factors and equations and transparent and consistent reporting of forest carbon inventories are needed in both scientific literature and the greenhouse gas inventory reports of countries.

Background Pasteurella multocida causes numerous economically relevant diseases in livestock including rabbits. Immunisation is only variably effective. Prophylactic antibiotics are used in some species but are contra-indicated in rabbits, due to their adverse effects on the rabbit microbiota. There is therefore a substantial need for alternative forms of infection control in rabbits; we investigated the effect of oral β-glucan on P. multocida infection in this species. Results Thirthy-five New Zealand White rabbits were randomly divided into five groups of seven animals. Three groups were inoculated with Pasteurella multocida intranasally (in.), a physiologically appropriate challenge which reproduces naturally acquired infection, and received either (1–3), (1–6) β-glucans or placebo. Four other groups were inoculated both in. and intramuscularly (im.), representing a supra-physiological challenge, and received either (1–3), (1–6) β-glucans, antibiotic or placebo. β-glucans given prophylactically were highly effective in protecting against physiological (in.) bacterial challenge. They were less effective in protecting against supra-physiological bacterial challenge (in. and im.), although they extended survival times. This latter finding has practical relevance to breeders as it extends the window in which heavily infected and symptomatic animals can be salvaged with antibiotics. Conclusions In our study, (1–3), (1–6) β-glucans were highly effective in protecting against a model of naturally acquired P. multocida infection and extended survival times in the supra-physiological model. Enrofloxacin was effective in protecting against supra-physiological infection. We are currently reviewing the use of combined prophylaxis. Electronic supplementary material The online version of this article (doi:10.1186/s12917-014-0276-6) contains supplementary material, which is available to authorized users.