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When modelling forest growth, capturing the effects of climate change is needed for reliable long-term predictions and management choices. This remains a challenge because commonly used mensurational forest growth and yield models, relying on inventory data, cannot account for climate change effects. We developed hybrid physiological/mensurational basal area growth and yield models, which combine physiological response to climatic conditions and empirical relations. We included climate and site effects by replacing time with light sums of photosynthetically active radiation and modifying the latter with monthly soil water, vapour pressure deficit, temperature, and frost days. When parameterised with permanent sample plot data for Scots pine and Norway spruce across Sweden, the hybrid models could reproduce observations well, although with no increase in precision compared with time-based mensurational models. When considering different climate scenarios, a significant impact on productivity from climate change emerged. For example, a 2 °C warming enhanced Scots pine production by up to 14% in regions where temperatures were originally cooler and soil water deficit was low (i.e. northwest Sweden), but depressed it, up to 9%, elsewhere. Hence, climate-sensitive models that take local variations into account are necessary for accurate predictions and sustainable forest management. [ABSTRACT FROM AUTHOR]

Farm specialization and associated simplification of the crop rotation raise concern about the ability of cropping systems to deliver high and stable yield in the long-term. Exploiting data from 52 years of a long-term experiment in Southern Sweden, we investigated impacts of three conventional cropping systems (‘crop-livestock’, ‘specialized’, and ‘diverse’) on yield levels and stability of winter and spring wheat. For winter wheat, the ‘diverse’ and ‘crop-livestock’ systems enhanced yields by 15% compared to the ‘specialized’ system. For spring wheat, the ‘crop-livestock’ system tended to show higher yield than the ‘diverse’ one. The stability analysis showed that in winter wheat the three systems lead to equally stable yields considering year-to-year variability. For spring wheat, the ‘crop-livestock’ system tended to perform better in favorable years relative to the other systems. Overall, the results revealed that for winter wheat cultivation, stockless diverse cropping provides an valid alternative to crop-livestock in the context of specialized farming where crop and livestock are separated. [ABSTRACT FROM AUTHOR]

• The ecological niche space for nitrogen (N) use traits was defined via n -dimensional hypervolumes. • Trait space was influenced more by the cultivar identity than crop mixing. • High N uptake was associated with a reduced overlap in niche-space in the mixtures. • Initial seed N pools contributed to N accumulation, shoot and tiller production. More efficient resource use, especially nitrogen (N) in agricultural fields could considerably reduce the losses and spillover effects on the environment. Cereal-legume mixtures can lead to more efficient uptake of growth-limiting resources, and increase and stabilize yields, due to the variation in functional traits that facilitate partitioning of niche space. Here we identify crop mixtures with functional traits that facilitate optimal N resource use in two selected cereal-legume mixtures by using the multi-dimensional trait space concept. Combinations of pea-barley and faba bean-wheat crops were grown in the field as pure cultures and mixtures in Central Sweden, during two years with contrasting weather. The ecological niche space was defined via the n -dimensional hypervolumes represented by N pool, tiller/branch number, shoot biomass, and grain yield functional traits. Regressions and correlations allowed quantifying the relations between functional traits and plant N pools. Differences in trait space were not a result of crop mixing per se , as similar hypervolumes were found in the pure culture and mixture-grown crops. Instead, the trait space differences depended on the cultivar identities admixed. Furthermore, cereals increased their efficiency for N uptake and therefore benefitted more than the legumes in the mixtures, in terms of accumulated N and grain yields. Tiller and shoot biomass production in cereals was positively correlated to N pool accumulation during the season. Resource acquisition through increased N uptake in the mixture was associated with a reduced overlap in niche-space in the mixtures, and initial seed N pools significantly contributed to within-season N accumulation, shoot and tiller production. [ABSTRACT FROM AUTHOR]