Scientific Journals of INIA (Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria)
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Short communication: Impact of the intensity of milk production on ammonia and greenhouse gas emissions in Portuguese cattle farms
Get PDFThe aim of this study was evaluate the relationship between the intensity of milk production for a wide range of Portuguese commercial cattle farms and NH3 and greenhouse gas (GHG) emissions from manure management and enteric fermentation. A survey was carried out at 1471 commercial dairy cattle farms (Holstein-Friesian) and the NH3, N2O and CH4 emissions at each stage of manure management were estimated as well as CH4 losses from enteric fermentation. Gaseous emissions were estimated by a mass flow approach and following the recommendations of IPCC guidelines. The manure management and enteric fermentation in a typical Portuguese cattle farm contributes with 7.5±0.15 g N/L milk produced as NH3 and 1.2±0.22 kg CO2 equivalent per litre of milk as GHG. Increasing milk production will significantly reduce NH3 and GHG emissions per litre of milk produced. It can be concluded that a win-win strategy for reducing NH3 and GHG emissions from dairy cattle farms will be the increase of milk production on these farms. This goal can be achieved by implementing animal breeding programs and improving feed efficiency in order to increase productivity
Modelling spatial patterns and temporal trends of wildfires in Galicia (NW Spain)
Get PDFAim of study: The goal of this paper is to analyse the importance of the main contributing factors to the occurrence of wildfires. Area of study: We employ data from the region of Galicia during 2001-2010; although the similarities shared between this area and other rural areas may allow extrapolation of the present results.Material and Methods: The spatial dependence is analysed by using the Moran’s I and LISA statistics. We also conduct an econometric analysis modelling both, the number of fires and the relative size of afflicted woodland area as dependent variables, which depend on the climatic, land cover variables, and socio-economic characteristics of the affected areas. Fixed effects and random effect models are estimated in order to control for the heterogeneity between the Forest Districts in Galicia.Main results: Moran’s I and LISA statistics show that there is spatial dependence in the occurrence of Galician wildfires. Econometrics models show that climatology, socioeconomic variables, and temporal trends are also important to study both, the number of wildfires and the burned-forest ratio.Research highlights: We conclude that in addition to direct forest actions, other agricultural or social public plans, can help to reduce wildfires in rural areas or wildland-urban areas. Based on these conclusions, a number of guidelines are provided that may foster the development of better forest management policies in order to reduce the occurrence of wildfires.Keywords: Cause-effect relationship; climatology; spatial and temporal indicators; fixed effects; random effects; socio-economic factors
Characterization of functional SSR markers in Prosopis alba and their transferability across Prosopis species
Get PDFAim of study: The aim of the study was to characterize functional microsatellite markers in Prosopis alba and examine the transferability to species from the Prosopis genus.Area of the study: samples were obtained from natural populations of Argentina.Material and Methods: Eleven SSR functional markers related to stress and metabolism were amplified in a sample of 152 genotypes from P. alba, P. denudans, P. hassleri P. chilensis, P. flexuosa, and interspecific hybrids.Main results: In P. alba, the PIC average value was 0.36; and 6 out of the 11 primers showed high values of polymorphism ranging from 0.40 to 0.71. The cross-species transferability was high with high percentages of polymorphic loci.Research highlights: The SSR markers developed in P.alba were easily transferred to other Prosopis species which did not have functional markers.Keywords: genetic variation; functional markers; microsatellites; prosopis.Abbreviations: PIC: Polymorphic Information Content; PCR: Polymerase Chain Reaction; SSR: Simple Sequence Repeat
An index for the assessment of degraded Mediterranean forest ecosystems
Get PDFAim of study: Diagnosing the degradation degree of forest ecosystems is the basis for restoration strategies. However, there is no literature documenting how to quantify the forest degradation degree by using synthetic indicators, also because there is not a widely accepted definition for "forest degradation" and "degraded forest". Although there are many definitions of forest degradation that converge on the loss of ecosystem services, still today there are no largely accepted methods that give operational guidance to help in defining it. In the present research, with the aim to assess the degree of forest degradation, an integrated index - FDI, Forest Degradation Index - was developed.Area of study: In this first application, the FDI was applied and validated at stand level in two different Mediterranean forest types in two different case studies: Madonie and Nedrodi regional Parks (Sicily, Italy). The first dominated by sessile oak [Quercus petraea (Matt.) Liebl. subsp. austrotyrrhenica Brullo, Guarino & Siracusa], the second dominated by cork oak (Quercus suber L.).Material and methods: FDI is a synthetic index structured starting from representative and relatively easily detectable parameters. Here, we propose a set of six indicators that should be assessed to determine the forest degradation: Structural Index (SI), Canopy Cover (CC), Natural Regeneration Density (NRD), Focal Species of Degradation (FSD), Coarse Woody Debris (CWD), and Soil Depth (SD). FDI, here proposed and discussed, has been based on a MCDA (Multi-Criteria Decision Analysis) approach using the Analytic Hierarchy Process (AHP) technique, and implemented in order to contribute in finding simple indicators useful for forest restoration purposes that have an eco-functional basis.Main results: An integrated index of forest degradation has been defined. FDI values are comprised in the closed interval [0, 10], ranging from class I (Higher ecological functionality) to class IV (Lower ecological functionality). A forest fallen in the FDI-IV class can be defined degraded. In this first application, degradation occurs in SA-4 and in SB-4 where the lowest values (qualitative and quantitative) of the indicators were recorded and the FDI reach the minimum value.Research highlights: FDI has proved to be a useful tool at stand level in identifying a threshold value below which a forest can be termed as ‘degraded’. In turn, FDI assumes the meaning of descriptor of the ecological functionality. Future development of the FDI will provide an extension of the application at landscape scale exploiting the potential advantages in coupling MCDA and GIS (Geographical Information Systems) techniques.Keywords: Forest Degradation Index (FDI); Sustainable Forest Management (SFM); Mediterranean Forest Landscape; Multi-Criteria Decision Analysis (MCDA) approach; Analytic Hierarchy Process (AHP).
Search for potential vectors of ‘Candidatus Liberibacter solanacearum’: population dynamics in host crops
Get PDF‘Candidatus Liberibacter solanacearum’ has recently been reported to be associated with vegetative disorders and economic losses in carrot and celery crops in Spain. The bacterium is a carrot seedborne pathogen and it is transmitted by psyllid vector species. From 2011 to 2014 seasonal and occasional surveys in carrot, celery and potato plots were performed. The sticky plant method was used to monitor the arthropods that visited the plants. The collected arthropods were classified into Aphididae and Cicadellidae, and the superfamily Psylloidea was identified to the species level. The superfamily Psylloidea represented 35.45% of the total arthropods captured on celery in Villena and 99.1% on carrot in Tenerife (Canary Islands). The maximum flight of psyllid species was in summer, both in mainland Spain and the Canary Islands, reaching a peak of 570 specimens in August in Villena and 6,063 in July in Tenerife. The main identified psyllid species were as follows: Bactericera trigonica Hodkinson, B. tremblayi Wagner and B. nigricornis Förster. B. trigonica represented more than 99% of the psyllids captured in the Canary Islands and 75% and 38% in 2011 and 2012 in Villena, respectively. In addition, Trioza urticae Linnaeus, Bactericera sp., Ctenarytaina sp., Cacopsylla sp., Trioza sp. and Psylla sp. were captured. ‘Ca. L. solanacearum’ targets were detected by squash real-time PCR in 19.5% of the psyllids belonging to the different Bactericera species. This paper reports at least three new psyllid species that carry the bacterium and can be considered as potential vectors
Relationships among slurry characteristics and gaseous emissions at different types of commercial Spanish pig farms
Get PDFThis study aimed to analyse several factors of variation of slurry composition and to establish prediction equations for potential methane (CH4) and ammonia (NH3) emissions. Seventy-nine feed and slurry samples were collected at two seasons (summer and winter) from commercial pig farms sited at two Spanish regions (Centre and Mediterranean). Nursery, growing-fattening, gestating and lactating facilities were sampled. Feed and slurry composition were determined, and potential CH4 and NH3 emissions measured at laboratory. Feed nutrient contents were used as covariates in the analysis. Near infrared reflectance spectroscopy (NIRS) was evaluated as a predicting tool for slurry composition and potential gaseous emissions. A wide variability was found both in feed and slurry composition. Mediterranean farms had a higher pH (p<0.001) and ash (p=0.02) concentration than those located at the Centre of Spain. Also, type of farm affected ether extract content of the slurry (p=0.02), with highest values obtained for the youngest animal facilities. Results suggested a buffer effect of dietary fibre on slurry pH and a direct relationship (p<0.05) with fibre constituents of manure. Dietary protein content did not affect slurry nitrogen content but decreased (p=0.003) total and volatile solids concentration. Prediction models of potential NH3 emissions (R2=0.89) and CH4 yield (R2=0.61) were obtained from slurry composition. Predictions from NIRS showed a high accuracy for most slurry constituents (R2>0.90) and similar accuracy of prediction of potential NH3 and CH4 emissions (R2=0.84 and 0.68, respectively) to models using slurry characteristics, which can be of interest to estimate emissions from commercial farms and establish mitigation strategies or optimize biogas production
Mating behaviour and gamete release in gilthead seabream (Sparus aurata, Linnaeus 1758) held in captivity
Get PDFThe present study aimed to describe the reproductive behaviour of gilthead seabream (Sparus aurata) in captivity. Twenty-four mature gilthead seabream, divided in two tanks, were utilized for the present study. Reproductive behaviour was recorded using submersibles cameras. A total of 67 spawning events were analysed. The mean duration time that gilthead seabream spent spawning was 54 ± 4 min/day, during which mean number of individual spawning events was 5.6 ± 0.2. The mean volume of eggs produced by both broodstocks was 405 ± 13.4 mL with a fertilization rate of 91.6 ± 0.4%. The reproductive behaviour began with a schooling behaviour and then forming light aggregations. From an aggregation or an encounter while swimming freely a female initiated a spawning rush followed by one or more males to gametes liberation. The spawning rush was brief, 1.6 ± 0.5 sec, over an approximately 1.7 ± 0.2 m distance from the tank bottom to the water surface. Pair spawning, between a single female and male, was the most common (71.6%). Group spawning was less common and involved a single female spawning with two males (22.5%) or three males (4.9%). Spawning rushes involving more than one female were not observed. Gilthead seabream in the present study presented a tendency to pair spawn and eggs collected as a “spawn” were actually the sum of many separate spawning events over a short time period. This is the first description of gilthead seabream spawning and the findings help to understand microsatellite based observations of spawning kinetics
Suitability of faecal near-infrared reflectance spectroscopy (NIRS) predictions for estimating gross calorific value
Get PDFA total of 220 faecal pig and poultry samples, collected from different experimental trials were employed with the aim to demonstrate the suitability of Near Infrared Reflectance Spectroscopy (NIRS) technology for estimation of gross calorific value on faeces as output products in energy balances studies. NIR spectra from dried and grounded faeces samples were analyzed using a Foss NIRSystem 6500 instrument, scanning over the wavelength range 400-2500 nm. Validation studies for quantitative analytical models were carried out to estimate the relevance of method performance associated to reference values to obtain an appropriate, accuracy and precision. The results for prediction of gross calorific value (GCV) of NIRS calibrations obtained for individual species showed high correlation coefficients comparing chemical analysis and NIRS predictions, ranged from 0.92 to 0.97 for poultry and pig. For external validation, the ratio between the standard error of cross validation (SECV) and the standard error of prediction (SEP) varied between 0.73 and 0.86 for poultry and pig respectively, indicating a sufficiently precision of calibrations. In addition a global model to estimate GCV in both species was developed and externally validated. It showed correlation coefficients of 0.99 for calibration, 0.98 for cross-validation and 0.97 for external validation. Finally, relative uncertainty was calculated for NIRS developed prediction models with the final value when applying individual NIRS species model of 1.3% and 1.5% for NIRS global prediction. This study suggests that NIRS is a suitable and accurate method for the determination of GCV in faeces, decreasing cost, timeless and for convenient handling of unpleasant samples
Development of a doorframe-typed swinging seedling pick-up device for automatic field transplantation
Get PDFA doorframe-typed swing seedling pick-up device for automatic field transplanters was developed and evaluated in a laboratory. The device, consisting of a path manipulator and two grippers, can move the pins slowly to extract seedlings from the tray cells and return quickly to the pick-up point for the next extraction. The path manipulator was constructed with the creative design of type-Ⅱ mechanism combination in series. It consists of an oscillating guide linkage mechanism and a grooved globoidal cam mechanism. The gripper is a pincette-type mechanism using the pick-up pins to penetrate into the root mass for seedling extraction. The dynamic analysis of the designed seedling pick-up device was simulated with ADAMS software. Being the first prototype, various performance tests under local production conditions were conducted to find out the optimal machine operation parameters and transplant production conditions. As the gripper with multiple fine pins was moved by the swing pick-up device, it can effectively complete the transplanting work cycle of extracting, transferring, and discharging a seedling. The laboratory evaluation showed that the pick-up device equipped with two grippers can extract 80 seedlings/min with a 90% success and a 3% failure in discharging seedlings, using 42-day-old tomato plantlets. The quality of extracting seedlings was satisfactory