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Monocultural rubber plantations have replaced tropical forest, causing biodiversity loss. While protecting intact or semi-intact biodiverse forest is paramount, improving biodiversity value within the 11.4 million hectares of existing rubber plantations could offer important conservation benefits, if yields are also maintained. Some farmers practice agroforestry with high-yielding clonal rubber varieties to increase and diversify incomes. Here, we ask whether such rubber agroforestry improves biodiversity value or affects rubber yields relative to monoculture. We surveyed birds, fruit-feeding butterflies and reptiles in 25 monocultural and 39 agroforest smallholder rubber plots in Thailand, the world’s biggest rubber producer. Management and vegetation structure data were collected from each plot, and landscape composition around plots was quantified. Rubber yield data were collected for a separate set of 34 monocultural and 47 agroforest rubber plots in the same region. Reported rubber yields did not differ between agroforests and monocultures, meaning adoption of agroforestry in this context should not increase land demand for natural rubber. Butterfly richness was greater in agroforests, where richness increased with greater natural forest extent in the landscape. Bird and reptile richness were similar between agroforests and monocultures, but bird richness increased with the height of herbaceous vegetation inside rubber plots. Species composition of butterflies differed between agroforests and monocultures, and in response to natural forest extent, while bird composition was influenced by herbaceous vegetation height within plots, the density of non-rubber trees within plots (representing agroforestry complexity), and natural forest extent in the landscape. Reptile composition was influenced by canopy cover and open habitat extent in the landscape. Conservation priority and forest-dependent birds were not supported within rubber. Synthesis and applications. Rubber agroforestry using clonal varieties provides modest biodiversity benefits relative to monocultures, without compromising yields. Agroforests may also generate ecosystem service and livelihood benefits. Management of monocultural rubber production to increase inter-row vegetation height and complexity may further benefit biodiversity. However, biodiversity losses from encroachment of rubber onto forests will not be offset by rubber agroforestry or rubber plot management. This evidence is important for developing guidelines around biodiversity-friendly rubber and sustainable supply chains, and for farmers interested in diversifying rubber production. The accompanying ReadMe.txt file explains the contents of each .csv file, including definitions of each column. Sampling protocols are outlined in the paper in Journal of Applied Ecology.

Replication package of the paper titled "An approach using performance models for supporting energy analysis of software systems". Usage instructions are contained in the README.md file.

Abstract. Dynamic global vegetation models are used to predict the response of vegetation to climate change. They are essential for planning ecosystem management, understanding carbon cycle–climate feedbacks, and evaluating the potential impacts of climate change on global ecosystems. JULES (the Joint UK Land Environment Simulator) represents terrestrial processes in the UK Hadley Centre family of models and in the first generation UK Earth System Model. Previously, JULES represented five plant functional types (PFTs): broadleaf trees, needle-leaf trees, C3 and C4 grasses, and shrubs. This study addresses three developments in JULES. First, trees and shrubs were split into deciduous and evergreen PFTs to better represent the range of leaf life spans and metabolic capacities that exists in nature. Second, we distinguished between temperate and tropical broadleaf evergreen trees. These first two changes result in a new set of nine PFTs: tropical and temperate broadleaf evergreen trees, broadleaf deciduous trees, needle-leaf evergreen and deciduous trees, C3 and C4 grasses, and evergreen and deciduous shrubs. Third, using data from the TRY database, we updated the relationship between leaf nitrogen and the maximum rate of carboxylation of Rubisco (Vcmax), and updated the leaf turnover and growth rates to include a trade-off between leaf life span and leaf mass per unit area.Overall, the simulation of gross and net primary productivity (GPP and NPP, respectively) is improved with the nine PFTs when compared to FLUXNET sites, a global GPP data set based on FLUXNET, and MODIS NPP. Compared to the standard five PFTs, the new nine PFTs simulate a higher GPP and NPP, with the exception of C3 grasses in cold environments and C4 grasses that were previously over-productive. On a biome scale, GPP is improved for all eight biomes evaluated and NPP is improved for most biomes – the exceptions being the tropical forests, savannahs, and extratropical mixed forests where simulated NPP is too high. With the new PFTs, the global present-day GPP and NPP are 128 and 62 Pg C year−1, respectively. We conclude that the inclusion of trait-based data and the evergreen/deciduous distinction has substantially improved productivity fluxes in JULES, in particular the representation of GPP. These developments increase the realism of JULES, enabling higher confidence in simulations of vegetation dynamics and carbon storage.

Abstract The combined production of electricity, heat and cold by a polygeneration system connected to a district heating and cooling network can provide high energy utilization efficiency. The inherent complexity of simultaneous production of different services and the high variability in the energy demand make combined cooling and heating systems performance highly dependent on the operational strategy. In this paper, an operational optimization method based on the moving average of real-time measurements of energy demands and ambient conditions is proposed. Real energy demand data from a district heating and cooling network close to Barcelona, Spain, are used to test the method. A complex polygeneration system is considered, consisting of an internal combustion engine, a double-effect absorption chiller, an electric chiller, a boiler and a cooling tower. A detailed modelling of the system is provided, considering partial load behavior of the components and ambient conditions effects. Results of the real-time optimal management are discussed and compared to traditional operational strategies and to the ideal optimal management achievable with perfectly accurate forecast of energy demands. Moreover, the optimal width of the window adopted for the moving average of real-time data is identified.

Abstract Floods are challenging the resilience of societies all over the world. In many countries there are discussions on diversifying the strategies for flood risk management, which implies some sort of policy change. To understand the possibilities of such change, a thorough understanding of the forces of stability and change of underlying governance arrangements is required. It follows from the path dependency literature that countries which rely strongly on flood infrastructures, as part of flood defense strategies, would be more path dependent. Consequently there is a higher chance to find more incremental change in these countries than in countries that have a more diversified set of strategies. However, comparative and detailed empirical studies that may help scrutinize this assumption are lacking. To address this knowledge gap, this paper investigates how six European countries (Belgium, England, France, The Netherlands, Poland and Sweden) essentially differ with regard to their governance of flood risks. To analyze stability and change, we focus on how countries are responding to certain societal and ecological driving forces (ecological turn; climate change discourses; European policies; and the increasing prevalence of economic rationalizations) that potentially affect the institutional arrangements for flood risk governance. Taking both the variety of flood risk governance in countries and their responses to driving forces into account, we can clarify the conditions of stability or change of flood risk governance arrangements more generally. The analysis shows that the national-level impact of driving forces is strongly influenced by the flood risk governance arrangements in the six countries. Path dependencies are indeed visible in countries with high investments in flood infrastructure accompanied by strongly institutionalized governance arrangements (Poland, the Netherlands) but not only there. Also more diversified countries that are less dependent on flood infrastructure and flood defense only (England) show path dependencies and mostly incremental change. More substantial changes are visible in countries that show moderate diversification of strategies (Belgium, France) or countries that ‘have no strong path yet’ in comprehensive flood risk governance (Sweden). This suggests that policy change can be expected when there is both the internal need and will to change and a barrage of (external) driving forces pushing for change.

New approach proposed for defining preconditions for human development Crossing certain biophysical thresholds could have disastrous consequences for humanity Three of nine interlinked planetary boundaries have already been overstepped

A mechanistic model is presented that describes the respiro-fermentative physiology of yeast. The model assumes the presence of multiple types of glucose carriers and multiple assimilation pathways. Respiro-fermentative physiology is explained by the mechanistic response of the different types of carriers and assimilation pathways on the substrate concentration. At low substrate concentrations, glucose is taken up mainly via a high affinity carrier with a low maximum uptake rate. At high substrate concentrations, this carrier becomes saturated and the main pathway for glucose uptake is via a low affinity carrier with a high maximum uptake rate. The price to pay for the high uptake rate is a lowered assimilation efficiency, resulting in a low biomass yield. Product formation occurs via the pathway with the high uptake rate. The model explains the link between substrate concentration and product formation generally observed in the literature on yeast and bacteria. Model parameter values are estimated by fitting data from the literature. The model distinguishes itself from other models in that it does not rely on the presence of switches, such as the 'critical dilution rate', or on the assumption that the respiratory capacity reaches its maximum during respiro-fermentative metabolism. The present theory is not designed exclusively for the phenomenon of respiro-fermentative physiology: it describes the degradation of substances by heterotrophic micro-organisms in general.