Search results for "Clima"
showing 10 items of 6069 documents
Climate and agriculture: empirical evidence for countries and agroecological zones of the Sahel
2022
International audience; ow heterogenous is the impact of climate change across space and the type of agricultural production? In this paper, we investigate the relationship between climate change and variability, measured by temperature and rainfall, and agricultural production at the country and agroecological zone levels of the Sahel. We consider a crop production index and five cereals (maize, millet, sorghum, wheat and rice). Based on an original climate database and an agricultural production function estimated for the period 1961–2016, we show that average rainfall and temperature during the growing season indeed have highly heterogeneous effects on agricultural production, depending …
Sustainable agriculture: Recognizing the potential of conflict as a positive driver for transformative change
2020
International audience; Transformative changes in agriculture at multiple scales are needed to ensure sustainability, i.e. achieving food security while fostering social justice and environmental integrity. These transformations go beyond technological fixes and require fundamental changes in cognitive, relational, structural and functional aspects of agricultural systems. However, research on agricultural transformations fails to engage deeply with underlying social aspects such as differing perceptions of sustainability, uncertainties and ambiguities, politics of knowledge, power imbalances and deficits in democracy. In this paper, we suggest that conflict is one manifestation of such und…
Editor in Chief. Agronomy for Sustainable Developmen
2012
PROD,2012-9 EA SAR CICAP UMR HORS POLE CT1 Enjeu2 INRA; International audience
Managing biotic interactions for ecological intensification of agroecosystems.
2014
9 pages; International audience; Agriculture faces the challenge of increasing food production while simultaneously reducing the use of inputs and delivering other ecosystem services. Ecological intensification of agriculture is a paradigm shift, which has recently been proposed to meet such challenges through the manipulation of biotic interactions. While this approach opens up new possibilities, there are many constraints related to the complexity of agroecosystems that make it difficult to implement. Future advances, which are essential to guide agricultural policy, require an eco-evolutionary framework to ensure that ecological intensification is beneficial in the long term.
Effects of density, species interactions, and environmental stochasticity on the dynamics of British bird communities
2022
Our knowledge of the factors affecting species abundances is mainly based on time-series analyses of a few well-studied species at single or few localities, but we know little about whether results from such analyses can be extrapolated to the community level. We apply a joint species distribution model to long-term time-series data on British bird communities to examine the relative contribution of intra- and interspecific density dependence at different spatial scales, as well as the influence of environmental stochasticity, to spatiotemporal interspecific variation in abundance. Intraspecific density dependence has the major structuring effect on these bird communities. In addition, envi…
Vulnerability of algae and seagrasses to climate change
2013
Biodiversity is undergoing rapid and worrying changes, partially driven by anthropogenic activities. Human impacts and climate change (e.g. increasing temperature and ocean acidification) represent the most serious threats to biodiversity and ecosystem functioning. Aim of this study was to assess, analysing the scientific literature and published data, how climate change can affect algae and seagrasses, evaluating their vulnerability and the possibility to use these organisms as indicators. Algae and seagrasses have a central role for several important ecological processes in aquatic ecosystems, and their loss can lead repercussions for the ecological function. Climate stressors affected ac…
Ca-rich carbonates associated with ultrabasic-ultramafic melts. Carbonatite or limestone xenoliths? A case study from the late Miocene Morron de Vill…
2016
The volcanic products of the late Miocene Morron de Villamayor volcano (Calatrava Volcanic Field, central Spain) are known for being one of the few outcrops of leucitites in the entire circum-Mediterranean area. These rocks are important because aragonite of mantle origin has been reported as inclusion in olivine macrocrysts. We use petrographic observations, mineral compositions, as well as oxygen and carbon isotope ratios coupled with experimental petrology to understand the origin of carbonate phase in these olivine-phyric rocks. Groundmass and macrocryst olivines range from δ18OVSMOW of +4.8‰, typical of mantle olivine values, to +7.4‰, indicating contamination by sedimentary carbonate.…
Alkaline pretreatment to enhance one-stage CH4 and two-stage H2/CH4 production from sunflower stalks: Mass, energy and economical balances
2015
Abstract Biological production of second generation biofuels such as biohydrogen (H2) or methane (CH4) represents a promising alternative to fossils fuels. Alkaline pretreatments of lignocellulosic biomass are known to enhance the accessibility and the bioconversion of hollocelluloses during anaerobic digestion and dark fermentation processes. In the present study, four different configurations were investigated: one-stage CH4 continuous and two-stage H2 batch/CH4 continuous process with and without alkaline pretreatment of sunflower stalks (55 °C, 24 h, 4 g NaOH/100 g TS). The results showed that two stage H2/CH4 (150 ± 3.5 mL CH4 g−1 VS) did not improve methane yields compared to one stag…
Biochemical methane potential (BMP) of solid organic substrates: evaluation of anaerobic biodegradability using data from an international interlabor…
2011
Background: This paper describes results obtained for different participating research groups in an interlaboratory study related to biochemical methane potential (BMP). In this research work, all experimental conditions influencing the test such as inoculum, substrate characteristics and experimental conditions were investigated. The study was performed using four substrates: three positive control substrates (starch, cellulose and gelatine), and one raw biomass material (mung bean) at two different inoculum to substrate ratios (ISR). Results: The average methane yields for starch, cellulose, gelatine and mung bean at ISR of 2 and 1 were 350 ± 33, 350 ± 29, 380 ± 42, 370 ± 36 and 370 ± 35 …
Variabilité climatique et profils organoleptiques du Pinot noir dans le monde
2015
Wine typicity is revealed at various spatial scales, according to the variability of terroir components, which individual contribution change depending on the site. In this study, the impact of climate at global scale on the sensory profile of wine is examined.Thirty one Pinot noir wines produced in 16 winegrowing regions in Europe (Germany, France and Switzerland), North America (USA), South America (Chile) and Oceania (Australia and New Zealand) were selected. A blind testing was performed on the wines by 14 judges; among which 9 were considered sufficiently repeatable (criteria evaluated from the sensory analysis results of two identical wines). Wines were described by 26 visual, olfacto…