Scientific Journals of INIA (Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria)
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AHP choice in cocoa post-harvest technology for small-scale farmers
Get PDFEnsuring that the post-harvest process yields good quality cocoa is a relevant research question. However, the literature currently lacks detailed studies of producers’ criteria for post-harvest technology selection. There is therefore a need for research that examines technology choice based on several criteria. This is the aim of our paper. We defined a cocoa post-harvest technology selection model to assist small producers in Ecuador. To do so, we employed the Analytical Hierarchy Process (AHP) to assess the following criteria: quality, processing cost and technology adoption capability. By considering only quality, we first performed a preliminary assessment of nine post-harvest technologies yielded by all possible combinations of fermentation and drying methods. Under the criterion “quality”, results show that no post-harvest technology is preferable to another. This implies that quality differences between producers do not derive from technology choice but rather from the rigour with which producers perform fermentation and drying processes. After adding the criteria “processing cost” and “technology adoption capability”, we performed the analysis again. This multi-criteria approach offered a better way to approximate small farmers’ real needs when selecting technology for cocoa post-harvest. Although quality was the highest-valued criterion, high scores attributed to some technologies in the other two criteria offset scores for quality. Thus, processing cost and technology adoption also emerged as relevant factors for small holders
Latent infections are the most frequent form of paratuberculosis in slaughtered Friesian cattle
Get PDFParatuberculosis is a chronic mycobacterial infection causing granulomatous enteritis in ruminants, whose pathogenesis and epidemiology poses numerous challenges, including latency and reactivation. The most recent and complete classification of paratuberculosis immunopathological types in cattle recognized five categories. In this study, 1031 slaughtered Friesian cattle were submitted to serological, microbiological and pathological examinations with the aim of maximizing the rate of case detection. In most cases, infected animals had minimal lesions and almost no other proof of infection (38.9%), while the more characteristic types with the whole constellation of microbiological and immunological evidences accounted for a lower proportion (7.7%). As these findings in cattle suggest similarities with the epidemiology of tuberculosis in humans, we propose to re-group the original immunopathological types into two broader paratuberculosis epidemio-pathogenic forms or states: latent and patent. The former term would define infections with focal lesions and might constitute an apparent resilience status representing a difficult to detect reservoir of infection whose role could become critical if later immune-compromising factors lead to re-activation. The latter would group those cases with multifocal and diffuse inflammatory lesions with higher mycobacterial load and viability suggestive of a more immediate epidemiological risk. Interestingly, the relative frequency of presentation of each profile varied with age. The proportion of latent forms remained relatively constant between 33.8% and 54.3% through adulthood from 3 years of age, while patent forms were more frequent during the first years of age and tended to decrease among the oldest individuals
Employing social accounting matrix multipliers to profile the bioeconomy in the EU member states: is there a structural pattern?
Get PDFThe concept of 'bioeconomy' is gathering momentum in European Union (EU) policy circles as a sustainable model of growth to reconcile continued wealth generation and employment with bio-based sustainable resource usage. Unfortunately, in the literature an economy-wide quantitative assessment covering the full diversity of this sector is lacking due to relatively poor data availability for disaggregated bio-based activities. This research represents a first step by employing social accounting matrices (SAMs) for each EU27 member encompassing a highly disaggregated treatment of traditional 'bio-based' agricultural and food activities, as well as additional identifiable bioeconomic activities from the national accounts data. Employing backward-linkage (BL), forward-linkage (FL) and employment multipliers, the aim is to profile and assess comparative structural patterns both across bioeconomic sectors and EU Member States. The results indicate six clusters of EU member countries with homogeneous bioeconomy structures. Within cluster statistical tests reveal a high tendency toward 'backward orientation' or demand driven wealth generation, whilst inter-cluster statistical comparisons by bio-based sector show only a moderate degree of heterogeneous BL wealth generation and, with the exception of only two sectors, a uniformly homogeneous degree of FL wealth generation. With the exception of forestry, fishing and wood activities, bio-based employment generation prospects are below non bioeconomy activities. Finally, milk and dairy are established as 'key sectors'
Microwave energy supplied by a prototype oven prevents the spread of Fusarium wilt during the propagation of melon plantlets by seed
Get PDFThe re-use of propagation trays in nursery greenhouses is one of the main ways in which fusarium wilt is spread in melon crops (Cucumis melo). The causal agent of the disease is the fungus Fusarium oxysporum f. sp. melonis. This paper reports that exposing these seed trays to the energy produced by a prototype microwave oven during the commercial production of melon plantlets can prevent the spread of this pathogen with only a very small increase in production costs
Short communication: Effect of the feed presentation form on the intake pattern, productive traits and rumen pH of beef cattle fed high concentrate diets
No full textNutritional disorders like ruminal acidosis are common in Spanish beef production system, in which animals are fed diets with a high content in starch. This experiment studied the effect of feed presentation form (concentrate and straw offered separately, CD, or mixed in form of briquettes, BR) on the pattern of intake, growth and rumen pH of beef cattle fed high concentrate diets. The experiment was performed with 40 Holstein male calves, 32 of them for determining feed intake pattern and productive rates, and the remaining 8, which were previously provided with a ruminal cannula, to monitor rumen pH in two 21-day consecutive periods following a change-over design. Animals fed BR reduced feed intake rate during the first hour after feeding (18.6 vs. 24.0% of daily intake p<0.001), but this diet promoted a lower rumen pH at all sampling times compared with CD (daily average of 5.98 vs. 6.33; p<0.001) and tended to promote a lower total feed intake (7.08 vs. 9.77 kg DM/d; p<0.001) and daily weight gain (1.43 vs. 1.76 kg/d; p=0.056). Offering the concentrate and the straw mixed in form of briquettes is not useful to prevent ruminal acidosis and improve growth, probably due to both a reduced particle size of straw and avoided self-regulation of straw intake along the day
Soil seed-bank germination patterns in natural pastures under different mineral fertilizer treatments
Get PDFDegraded native grasslands in Mediterranean areas can be improved by encouraging seedling regeneration from soil seed banks using chemical fertilization. The effect of mineral fertilizers on soil seed banks was studied in natural pastures at two locations in southern Italy: Carpino and Rignano Garganico. The aim was to determine if nitrogen (N), phosphorus (P) and combined nitrogen and phosphorus (NP) fertilization can promote increased soil seed density. The seed-bank size and composition were analysed over two growth cycles (2004-2006) at two periods of the year: at the early summer and at the early autumn. The plant species were classified into three functional groups: grasses, legumes and other species (all other dicots). A two-pool model (ephemeral and base pools) derived from the germination patterns was developed to quantify the dynamics of the germinated seed populations. The mean total seed number in the seed bank ranged from 2,915 to 4,782 seed m-2 with higher values in early summer than in early autumn. Mineral fertilizer applications increased the seed-bank size (by 27%, 23% and 46%, for N, P and NP, respectively) and modified the composition in both localities. The three plant functional groups showed different potentials for ephemeral and persistent seed-bank production; however, within each plant group, the proportion between the ephemeral and base pool fractions did not change with fertilizer application. These data show that mineral fertilization can have positive effects on the seed-bank size of ungrazed natural pastures, and can be used to improve degraded Mediterranean pastures
Species richness of vascular plants along the climatic range of the Spanish dehesas at two spatial scales
No full textAims of study: The goals of this paper are to summarize and to compare plant species richness and floristic similarity at two spatial scales; mesohabitat (normal, eutrophic, and oligotrophic dehesas) and dehesa habitat; and to establish guidelines for conserving species diversity in dehesas.Area of study: We considered four dehesa sites in the western Peninsular Spain, located along a climatic and biogeographic gradient from north to south. Main results: Average alpha richness for mesohabitats was 75.6 species, and average alpha richness for dehesa sites was 146.3. Gamma richness assessed for the overall dehesa habitat was 340.0 species. The species richness figures of normal dehesa mesohabitat were significantly lesser than of the eutrophic mesohabitat and lesser than the oligotrophic mesohabitat too. No significant differences were found for species richness among dehesa sites. We have found more dissimilarity at local scale (mesohabitat) than at regional scale (habitat). Finally, the results of the similarity assessment between dehesa sites reflected both climatic and biogeographic gradients.Research highlights: An effective conservation of dehesas must take into account local and regional conditions all along their distribution range for ensuring the conservation of the main vascular plant species assemblages as well as the associated fauna.Keywords: Agroforestry systems; mesohabitat; non-parametric estimators; alpha richness; gamma richness; floristic similarity; climatic and biogeographic range
Using a segmented logistic model to predict trees to be harvested in forest growth forecasts
Get PDFAim of the study: Predicting future harvested trees is a prerequisite to growth forecasts in managed forest stands. While harvest algorithms have been traditionally used, statistical harvest models could be an interesting alternative approach. The objective of this study was to fit statistical harvest models for different partial cutting treatments.Area of study: The study has been carried out in the province of Quebec, Canada.Material and Methods: Data from provincial control survey were used to fit harvest models for three different partial cutting treatments. A two-segment logistic modelling approach was used. The harvest models were designed to be compatible with the ARTEMIS growth simulator, which is currently in use in this province. Main results: The results showed that the probability of being harvested is different across the treatments and primarily depends on tree diameter at breast height and species. In selection cutting treatments in particular, trees close to the merchantable limit (e.g., 23 cm in this study) tended to be less frequently harvested than those with smaller or larger diameters, yielding a sinusoidal pattern that was well captured by the segmented approach. Research highlights: Although the models were of average accuracy as indicated by fit statistics, they made it possible to compare different scenarios in terms of productivity and rotation length when coupled with the ARTEMIS growth simulator. Moreover, compatibility requirements between the simulator and the harvest models appeared to be a major limitation in some cases.Keywords: Harvesting; statistical model; segmented approach; growth forecasts; managed stands
A comparison of different methods to estimate species proportions by area in mixed stands
Get PDFAim of the study: This paper presents the most appropriate ways to estimate the species proportions by area in mixed stands of Norway spruce (Picea abies L. Karst.) and European beech (Fagus sylvatica L.) by comparing stand level and individual tree level approaches. It also investigates whether different ways of describing species proportions by area can result in different judgments on the over- or under-yielding of species in mixtures.Area of the study: Three triplets of pure and mixed stands of Norway spruce and European beech in three locations in the northeast of Austria are investigated. The three locations differ considerably in slope, bedrock and soil type as well as in site index.Material and Methods: In all 9 plots the coordinates of all trees, their dbh, height, height to the crown base and five year increment were measured. The potentially available areas of individual trees are calculated by Voronoi- diagrams and potential densities are estimated from the comparable pure stands, yield tables, and published equations for maximum basal area and Reineke’s maximum density line.Main results: The species proportions estimated by the individual tree approach with leaf area as growth characteristic gave the best fit with the stand approach with the most appropriate, regional maximum basal area equations. By using various definitions of species proportions, in the worst case the mixing effects on individual species can be seriously over- or underestimated while the mixing effects on the total increment is only negligibly affected.Research highlightsMeasures of species proportions by area are needed for comparing growth per hectare of a species in a mixed stand with that of the same species in a pure standSpecies proportions at the stand level are based on estimates of the species’ potential densities, either in terms of maximum basal area or of maximum stand density indexSpecies proportions at the tree level are derived from the area potentially available (APA) to the individual trees, based on the coordinates of trees in the stands, and on their growth characteristics, such as crown projection area or leaf areaFor the examples of Norway spruce - European beech stands, the species proportions derived according to the individual tree approach using leaf area as growth characteristics fits best with the stand approach using the most appropriate maximum basal area equationsKeywords: Picea abies; Fagus sylvatica; mixture proportion; growth efficiency; mixing effect.Abbreviations used: APA – area potentially available
Carbon storage in HWP. Accounting for Spanish particleboard and fiberboard
Get PDFAim of study: The study quantifies carbon stock in particleboard and fibreboard, for the period 1990-2006. It is the first accounting made for the Spanish wood industry using industrial accurate data and it could be comparable to other European studies.Area of study: SpainMaterial and Methods: A comparison of the three different approaches (Stock Change Approach, Production Approach, Atmospheric Flow Approach) of the 2006 Intergovernmental Panel on Climate Change Guidelines for National Greenhouse Gas (GHG). Due to the complexity derived from the amount of input variables and the recurrence of the formulas, the Montecarlo simulation method was chosen to compare results.Main results: Between 1990-2006 the carbon stock of the Spanish panel industry has been growing steadily, reaching around 1,000 Gg C in all three approaches studied. During the period 1990-2002, the Stock Change Approach is the one which provides a higher carbon stock accounting. However, since 2002 the Production Approach is the one which presents higher values of carbon stock.Research highlights: The main result of the study shows the important role of carbon stock which play the Spanish wood based panel industry during the period analysed. The results highlight the economic and environmental importance of carbon stock stored in such wood products, as well as its remarkable increase during the study period. They also highlights the importance of good practices such as cascade use of wood resources as well as the need for properly coordination between climate change and forest policies.Key words: climate change; emissions trading system; national greenhouse gas inventories; approach; Monte Carlo; recycled wood; cascade use