28 research outputs found
Supplying new cocoa planting material to farmers: a review of propagation methodologies
The review, coordinated by Bioversity International, presents an impartial, evidence-based review of cacao propagation methods, to serve as a basis for the assessment and implementation of strategies for providing farmers with quality planting materials, adapted to current and future needs (cultural, institutional, technical, environmental and financial). It describes the various propagation methods available for the production and supply of large numbers of cacao plants to growers. It is hoped that the result of the efforts of the key authors provides a basis to build on for case-specific recommendations. As the supply of new improved planting material to farmers is at the heart of improving cocoa productivity and modernizing the crop, we hope that the information in the review will make its way into national cocoa plans, and help to make cocoa farming more attractive and more sustainable
Microtiming patterns and interactions with musical properties in Samba music
In this study, we focus on the interaction between microtiming patterns and several musical properties: intensity, meter and spectral characteristics. The data-set of 106 musical audio excerpts is processed by means of an auditory model and then divided into several spectral regions and metric levels. The resulting segments are described in terms of their musical properties, over which patterns of peak positions and their intensities are sought. A clustering algorithm is used to systematize the process of pattern detection. The results confirm previously reported anticipations of the third and fourth semiquavers in a beat. We also argue that these patterns of microtiming deviations interact with different profiles of intensities that change according to the metrical structure and spectral characteristics. In particular, we suggest two new findings: (i) a small delay of microtiming positions at the lower end of the spectrum on the first semiquaver of each beat and (ii) systematic forms of accelerando and ritardando at a microtiming level covering two-beat and four-beat phrases. The results demonstrate the importance of multidimensional interactions with timing aspects of music. However, more research is needed in order to find proper representations for rhythm and microtiming aspects in such contexts
Star formation efficiency in galaxy clusters
The luminous material in clusters of galaxies falls primarily into two forms:
the visible galaxies and the X-ray emitting intra-cluster medium. The hot
intra-cluster gas is the major observed baryonic component of clusters, about
six times more massive than the stellar component. The mass contained within
visible galaxies amounts to approximately 3% of the dynamical mass. Our aim was
to analyze both baryonic components, combining X-ray and optical data of a
sample of five galaxy clusters (Abell 496, 1689, 2050, 2631 and 2667), within
the redshift range 0.03 < z < 0.3. We determined the contribution of stars in
galaxies and the intra-cluster medium to the total baryon budget. We used
public XMM-Newton data to determine the gas mass and to obtain the X-ray
substructures. Using the optical counterparts from SDSS or CFHT we determined
the stellar contribution. We examine the relative contribution of galaxies,
intra-cluster light and intra-cluster medium to baryon budget in clusters
through the stellar-to-gas mass ratio, estimated with use of recent data. We
find that the stellar-to-gas mass ratio within r_500 (the radius which the mean
cluster density exceeds the critical density by a factor of 500), is
anti-correlated with the ICM temperature, ranging from 24% to 6% whereas the
temperature ranges from 4.0 to 8.3 keV. This indicates that less massive cold
clusters are more prolific star forming environments than massive hot clusters.Comment: A&A in press, 15 pages, 9 figure
Land-use change and carbon stocks: regional assessment of sugarcane areas in Brazil.
Abstract: In agricultural product Life Cycle Assessment (LCA), emissions or removals of carbon (C) from land-use change can highly affect the global warming. The aim of this study was to evaluate the impacts of biomass C values and stock change factors on land use change (LUC) emissions in areas of sugarcane expansion in Brazil. In this study, we used stratified random sample in order to estimate changes in land cover through geotechnologies and associated C stocks from literature data. For that, the total area was stratified by three criteria: soil type, % of native vegetation in 1998 and age of sugarcane plantation in 2018. The sample size represented 12.8% of the studied area (172,000 ha). To this end, a matrix of primary combinations was combined with spatial data such as land cover in 1998, soil types, biomes and Köppen climate classification. Estimates of C stock changes in soil and biomass were calculated the Stock-Difference Method, according to IPCC Guidelines and specialized literature. Respecting the uncertainties, this approach allowed to have an estimate of C balance in sugarcane fields at the regional level in Brazil. Three main recommendations: (i) values of FMG> 1.0 (FMG, stock change factor for management regime), should be used for sugarcane, but future research ratification is necessary; (ii) biomass C values of sugarcane biomass above 5 tonnes C ha-1 should be used, especially when sugarcane is harvested without burning; and (iii) as there is still no relationship between level of pasture degradation and C content in soil, biomass C values and pasture FMG should be carefully chosen in pasture conversion to sugarcane
Life cycle analysis improvement in the ethanol chain: using geoprocessing to estimate the variation of soil carbon stocks.
Abstract: Land Use Change (LUC) has great relevance for Brazilian overall CO2 emissions. Considering its relationship to agricultural production, especially for biofuels and biomaterials production, it becomes paramount to understand and replicate improvements on the methodologies to measure LUC in the ethanol chain. The objective of this work is to reduce uncertainties and to ensure traceability in the calculation of the variation of carbon stock in the soil and Biomass, during the ethanol production process in Brazil aiming at a complete LCA of the product. In this sense, Braskem, the world\'s largest producer of biopolymers, Atvos the largest supplier of ethanol, Embrapa (Brazilian Agricultural Research Company) and Quantis (Swiss sustainability consultancy) joined together to experiment a method of estimating LUC emissions, which will feedback the process to help to develop a LUC accounting guidance