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Ma, S., Lardy, R., Graux, A. - I., Ben Touhami, H., Klumpp, K., Martin, R., et al. (2015). Regional-scale analysis of carbon and water cycles on managed grassland systems. Env. Model. Softw., 72, 356–371.
Abstract: Predicting regional and global carbon (C) and water dynamics on grasslands has become of major interest, as grasslands are one of the most widespread vegetation types worldwide, providing a number of ecosystem services (such as forage production and C storage). The present study is a contribution to a regional-scale analysis of the C and water cycles on managed grasslands. The mechanistic biogeochemical model PaSim (Pasture Simulation model) was evaluated at 12 grassland sites in Europe. A new parameterization was obtained on a common set of eco-physiological parameters, which represented an improvement of previous parameterization schemes (essentially obtained via calibration at specific sites). We found that C and water fluxes estimated with the parameter set are in good agreement with observations. The model with the new parameters estimated that European grassland are a sink of C with 213 g C m(-2) yr(-1), which is close to the observed net ecosystem exchange (NEE) flux of the studied sites (185 g C m(-2) yr(-1) on average). The estimated yearly average gross primary productivity (GPP) and ecosystem respiration (RECO) for all of the study sites are 1220 and 1006 g C m(-2) yr(-1), respectively, in agreement with observed average GPP (1230 g C m(-2) yr(-1)) and RECO (1046 g C m(-2) yr(-1)). For both variables aggregated on a weekly basis, the root mean square error (RMSE) was similar to 5-16 g C week(-1) across the study sites, while the goodness of fit (R-2) was similar to 0.4-0.9. For evapotranspiration (ET), the average value of simulated ET (415 mmyr(-1)) for all sites and years is close to the average value of the observed ET (451 mm yr(-1)) by flux towers (on a weekly basis, RMSE similar to 2-8 mm week(-1); R-2 = 0.3-0.9). However, further model development is needed to better represent soil water dynamics under dry conditions and soil temperature in winter. A quantification of the uncertainties introduced by spatially generalized parameter values in C and water exchange estimates is also necessary. In addition, some uncertainties in the input management data call for the need to improve the quality of the observational system.
Keywords: carbon flux; eddy flux measurements; model evaluation; pasture simulation model (pasim); water balance; pasture simulation-model; nitrous-oxide emissions; primary productivity npp; comparing global-models; net ecosystem exchange; greenhouse-gas balance; climate-change; agricultural systems; co2 exchange; european grasslands
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Ghaley, B. B., Sandhu, H. S., & Porter, J. R. (2015). Relationship between C:N/C:O stoichiometry and ecosystem services in managed production systems. PLoS One, 10(4), e0123869.
Abstract: Land use and management intensity can influence provision of ecosystem services (ES). We argue that forest/agroforestry production systems are characterized by relatively higher C:O/C:N and ES value compared to arable production systems. Field investigations on C:N/C:O and 15 ES were determined in three diverse production systems: wheat monoculture (Cwheat), a combined food and energy system (CFE) and a beech forest in Denmark. The C:N/C:O ratios were 194.1/1.68, 94.1/1.57 and 59.5/1.45 for beech forest, CFE and Cwheat, respectively. The economic value of the non-marketed ES was also highest in beech forest (US$ 1089 ha(-1) yr(-1)) followed by CFE (US$ 800 ha(-1) yr(-1)) and Cwheat (US$ 339 ha(-1) yr(-1)). The combined economic value was highest in the CFE (US$ 3143 ha(-1) yr(-1)) as compared to the Cwheat (US$ 2767 ha(-1) yr(-1)) and beech forest (US$ 2365 ha(-1) yr(-1)). We argue that C:N/C:O can be used as a proxy of ES, particularly for the non-marketed ES, such as regulating, supporting and cultural services. These ES play a vital role in the sustainable production of food and energy. Therefore, they should be considered in decision making and developing appropriate policy responses for land use management.
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Baker, A., Ceasar, S. A., Palmer, A. J., Paterson, J. B., Qi, W., Muench, S. P., et al. (2015). Replace, reuse, recycle: improving the sustainable use of phosphorus by plants. J. Experim. Bot., 66(12), 3523–3540.
Abstract: The ‘phosphorus problem’ has recently received strong interest with two distinct strands of importance. The first is that too much phosphorus (P) is entering into waste water, creating a significant economic and ecological problem. Secondly, while agricultural demand for phosphate fertilizer is increasing to maintain crop yields, rock phosphate reserves are rapidly declining. Unravelling the mechanisms by which plants sense, respond to, and acquire phosphate can address both problems, allowing the development of crop plants that are more efficient at acquiring and using limited amounts of phosphate while at the same time improving the potential of plants and other photosynthetic organisms for nutrient recapture and recycling from waste water. In this review, we attempt to synthesize these important but often disparate parts of the debate in a holistic fashion, since solutions to such a complex problem require integrated and multidisciplinary approaches that address both P supply and demand. Rapid progress has been made recently in our understanding of local and systemic signalling mechanisms for phosphate, and of expression and regulation of membrane proteins that take phosphate up from the environment and transport it within the plant. We discuss the current state of understanding of such mechanisms involved in sensing and responding to phosphate stress. We also discuss approaches to improve the P-use efficiency of crop plants and future direction for sustainable use of P, including use of photosynthetic organisms for recapture of P from waste waters.
Keywords: Conservation of Natural Resources; Crops, Agricultural/growth & development/metabolism; Gene Expression Regulation, Plant; Phosphorus/*metabolism; Plant Proteins/genetics/metabolism; Plants/genetics/*metabolism; Fertilizers; membrane transporters; nutrient recycling; phosphate; phosphate signalling; transcription factors
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Kjeldsen, C., Sørensen, A. - M. L., Dalgaard, T., & Graversgard, M. (2015). Report on cross-cutting approaches for the assessment of climate change adaption on selected EU sites or hotspots and potentials for adaption and mitigation in the dairy sector (Vol. 6).
Abstract: Adaption to climate change in the context of agriculture involves collaborative planning and development of practices which is deemed more sustainable than preceeding practices. It is however not given that sustainable development will be the outcome of such efforts. In some cases, even motivated participants experience that despite good intentions, high levels of knowledge, feasible models, appropriate technologies and many other factors present, they still might not succeed bringing about the desired change. The reasons for this can not easily be reduced to just one factor, but is very likely to be the outcome of highly complex interactions between social, technological, institutional, or even personal factors. The report documents attempts to understand the complexities of climate change adaption in a Danish water catchment, Lundgaards Bæk, which is dominated by dairy farming. As part of the EU projects AQUARIUS and MACSUR, a local action group was formed which was composed of local farmers, local agricultural advisors, advisors from the national agricultural advisory service, environmental planners from the local municipality, and environmental planners from the national environmental agency in Denmark. The action group was supposed to develop specific measures, which were supposed to lead to an overall reduction in nitrogen loading of the neighboring fjord, Mariager Fjord. The report addresses three related research themes: (1) how do the stakeholders in question interact during the process of climate change adaption, (2) when do the stakeholders encounter opportunities and barriers during the process, and finally (3) does the adaption process in question lead to the desired outcomes? The empirical background of the report is a detailed process study of dynamics within a group of stakeholders, including farmers and extension officers, who were supposed to develop sustainable management practices in order to reduce nitrogen leaching to the Mariager Fjord. The study is based on the assumption that in order for research and policy to contribute to sustainable practices, deeper understanding of complex dynamics within stakeholder partnerships is needed. Based on a theoretical framework derived from social learning, adaptive co-management and Andrew Pickering’s notion of ‘the mangle’, different in-depth explanations to why sustainable development did not occur, are offered. One explanation concerns social-psychological dynamics of knowledge. Another explanation concerns the mechanisms by which social and material forces affect outcomes of the adaption process. The report concludes by exploring the study’s relevance in relation to policy, research and practice, followed by suggestions for further in-depth case studies and experimentation in practice. No Label
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Lacetera, N., Vitali, A., Bernabucci, U., & Nardone, A. (2015). Report on relationships between THI and dairy cow performance (Vol. 4).
Abstract: The work carried out under LiveM, L1.2 and described herein was based on construction and query of large databases which included multiannual productive and health field data. Productive data referred to dairy cows and included milk yield and composition, whereas health data were relative both to dairy cows and pigs. The analysis established the THI values above which a significant decline in the performance and health of dairy cows or pigs is to be expected. These results may help to adopt management environmental strategies which may permit to limit THI increase under farming conditions and/or to provide animals with interventions which may reduce heat load and/or increase dissipation of heat. No Label
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