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291.
292.
- 1. A review of floristic studies on the Galician maërl community (north‐west Spain) and updated information on the distribution of maërl beds, their associated flora and long‐term changes is presented.
- 2. The Galician maërl community has been poorly studied; most of the previous studies were of short duration and focused on isolated beds. Studies on the associated maërl flora and overall Galician maërl bed distribution are required to put these in context with other Atlantic and Mediterranean European areas.
- 3. A literature review of all Galician studies produced a list of 198 maërl associated species (204 infraspecific taxa including life history stages) recorded from a total of 111 maërl beds. The current survey (2003–2006) increased the Galician maërl epiflora records to 226 species (232 intraspecific taxa including life history stages: 9 Cyanophyta, 160 Rhodophyta, 36 Heterokontophyta and 27 Chlorophyta), highlighting the occurrence of 10 non‐native species. The current Galician catalogue is compared with maërl studies from different Atlantic and Mediterranean regions.
- 4. In order to assess the long‐term changes in Galician maërl beds and their conservation status, 60 maërl beds which have been previously studied by various different workers were resampled to compare their current distribution, area and cover with historical data from the literature.
- 5. A reduction in the study area of maërl beds and their cover was detected. Most of the lost maërl areas were within or in the vicinity of myticulture areas where burial of maërl by fine sediment has a deleterious effect.
293.
An online operational alert system for the early detection of shrimp epidemics at the regional level based on real-time production 总被引:1,自引:0,他引:1
Bonny Bayot Stanislaus Sonnenholzner Xavier Ochoa Johanna Guerrerro Teresa Vera Jorge Caldern Ignacio de Blas María del Pilar Cornejo-Grunauer Sam Stern Frans Ollevier 《Aquaculture (Amsterdam, Netherlands)》2008,277(3-4):164-173
Diseases are among the greatest threats affecting the sustainability of shrimp aquaculture. In Ecuador, diseases of cultured shrimp have been quickly transmitted from one region to another. Therefore, an early detection system of impending epidemics could serve as an important management tool for the aquaculture sector. We developed a system for the early detection of shrimp epidemics for the largest shrimp zone of Ecuador based on production surveillance. The system, called Epidemiological Alert System and Aquaculture Management (SAEMA), uses a geographical information system (GIS) with an imaginary grid cartography (12,860 ha per grid) dividing the study area. A production and management index is calculated with the harvest data of each pond. A standardized deviation around the historical averages and an alert level is calculated per grid and month. Normal conditions of production and therefore the absence of disease are depicted in green and yellow. While, orange and red colours express a disease warning manifested through suboptimal production levels. As a result, a map of the study area with grid divisions is displayed, with a specific alert colour for each grid where information is available. SAEMA was developed as a Web application (http://www.saema.espol.edu.ec) that enables producers to record data via a worksheet format using any web browser. Instantaneously, the applications perform a calculation of the alert index and provide feedback to the alert levels displayed in an interactive map. A feedback process was initiated in May 2006 with 19 participating shrimp farms. The objective of this research is to develop a platform for an early detection of shrimp epidemics on a regional scale. The detection of an epidemic, expressed as suboptimal production in a specific region, can provide producers from other zones and government authorities to engage in time preventive and control measures in order to reduce the spread of diseases. 相似文献
294.
Carolina Paula BIANCHI Santiago BRUNO Ignacio VIDELA DORNA Edgardo RODRÍGUEZ Marcelo Alfredo ABA 《Journal of Equine Science》2022,33(1):1
In study I, plasma progesterone concentrations were evaluated in anoestrous mares that received an intravaginal progesterone release device (IPRD) for 10 days. Mares were divided into 3 groups based on the dosage of progesterone (0 g, n=3; 1.38 g, n=5; and 1.9 g, n=5). No statistical differences were found in plasma progesterone concentrations between the two doses tested. In study II, the effects of a protocol based on a short program of artificial light combined with an IPRD containing 1.38 g of progesterone on oestrous behaviour and onset of ovulation were evaluated. IPRDs were inserted into 31 late transitional mares (10 days of treatment). The mares were divided into a control group (n=9, IPRD with 0 g of progesterone) and two treatment groups (T1, n=10, IPRD with 0 g of progesterone and artificial light; T2, n=12, IPRD with 1.38 g of progesterone and artificial light). The percentages of mares in heat within the first 14 days after treatment were 100%, 70%, and 100% in the control, T1, and T2 groups, respectively (P=0.097), and their ovulation rates were 44%, 60%, and 100%, respectively (P≤0.01). In conclusion, a protocol based on artificial light and an IPRD containing 1.38 g of progesterone for 10 days could be considered to advance the first ovulation of the year in late transitional mares, as it ensures a higher rate of ovulation within the first 14 days after treatment. 相似文献
295.
ZigBee-based wireless sensor network localization for cattle monitoring in grazing fields 总被引:7,自引:0,他引:7
Juan Ignacio Huircán Héctor Young Jaime Bustos Marcelo Toneatti 《Computers and Electronics in Agriculture》2010,74(2):258-264
This paper presents the design of a localization scheme in wireless sensor networks (WSN) for cattle monitoring applications in grazing fields. No additional hardware was required for distance estimation since they were performed using the link quality indication (LQI), which is a standard feature of the ZigBee protocol. The ratiometric vector iteration (RVI) algorithm was implemented and modified to work with LQI measurements instead of the usual received signal strength indication (RSSI). Experimental results show acceptable localization performance given the requirements of usual cattle monitoring applications at low cost and low power consumption. 相似文献
296.
Ignacio Martín Jose Ramón Gutierrez Juan Antonio Martos‐Sitcha Inmaculada Rasines Cristina Rodríguez Juan Miguel Mancera Olvido Chereguini 《Aquaculture Research》2017,48(7):3393-3400
This study aimed to determine the maximum time of emersion of Senegalese sole (Solea senegalensis) specimens to form the basis for a dry sole transport procedure. For this purpose, 56 specimens (922.33 ± 29.52 g body weight) were individually placed in polystyrene boxes on a wet cloth, maintaining constant temperature (15°C) during emersion trial. Specimens (n = 7 per group) were sampled for plasma, and mortality was monitored at different points (0, 2, 6, 12, 20, 28, 36 and 44 h of emersion), and several stress (cortisol, glucose and lactate) and metabolic (triglycerides, proteins and amino acids) parameters were assessed. After sampling, each experimental group was placed in recovery tanks for the assessment of delayed mortality and feeding performance after emersion trial. Transport periods longer than 28 h produced high stress level indicated by (i) significant increase in circulating cortisol and lactate and (ii) glucose reserves mobilization. These alterations originated physiological problems during the emersion trial that induced mortality as well as problems for recovering correct feeding performance of specimens. These results suggested that at 15°C for S. senegalensis specimens (around 900 g body weight), a waterless transport is possible without direct or delayed mortality up to 28 h. 相似文献
297.
Alida Bundy Ratana Chuenpagdee Jennifer L Boldt Maria de Fatima Borges Mohamed Lamine Camara Marta Coll Ibrahima Diallo Clive Fox Elizabeth A Fulton Ayse Gazihan Astrid Jarre Didier Jouffre Kristin M Kleisner Ben Knight Jason Link Patroba P Matiku Hicham Masski Dimitrios K Moutopoulos Chiara Piroddi Tiit Raid Ignacio Sobrino Jorge Tam Djiga Thiao Maria Angeles Torres Konstantinos Tsagarakis Gro I van der Meeren Yunne‐Jai Shin 《Fish and Fisheries》2017,18(3):412-439
Fisheries have had major negative impacts on marine ecosystems, and effective fisheries management and governance are needed to achieve sustainable fisheries, biodiversity conservation goals and thus good ecosystem status. To date, the IndiSeas programme (Indicators for the Seas) has focussed on assessing the ecological impacts of fishing at the ecosystem scale using ecological indicators. Here, we explore fisheries ‘Management Effectiveness’ and ‘Governance Quality’ and relate this to ecosystem health and status. We developed a dedicated expert survey, focused at the ecosystem level, with a series of questions addressing aspects of management and governance, from an ecosystem‐based perspective, using objective and evidence‐based criteria. The survey was completed by ecosystem experts (managers and scientists) and results analysed using ranking and multivariate methods. Results were further examined for selected ecosystems, using expert knowledge, to explore the overall findings in greater depth. Higher scores for ‘Management Effectiveness’ and ‘Governance Quality’ were significantly and positively related to ecosystems with better ecological status. Key factors that point to success in delivering fisheries and conservation objectives were as follows: the use of reference points for management, frequent review of stock assessments, whether Illegal, Unreported and Unregulated (IUU) catches were being accounted for and addressed, and the inclusion of stakeholders. Additionally, we found that the implementation of a long‐term management plan, including economic and social dimensions of fisheries in exploited ecosystems, was a key factor in successful, sustainable fisheries management. Our results support the thesis that good ecosystem‐based management and governance, sustainable fisheries and healthy ecosystems go together. 相似文献
298.
Performance assessment of an irrigation scheme using indicators determined with remote sensing techniques 总被引:1,自引:1,他引:0
In this work, remote sensing-based assessments of actual evapotranspiration using METRIC integrated with a water balance model
provided accurate estimates of irrigation performance. This new methodology was applied and tested in the Genil–Cabra Irrigation
Scheme located in southern Spain during the 2004–2005 irrigation season. The performance indicators used, the annual relative
irrigation supply (ARIS) and the irrigation water productivity (IWP), required ET input data which were calculated using either
METRIC or standard FAO methodology. The new procedure that used METRIC detected overirrigation (ARIS of 1.27) in situations
where the ARIS calculated with the standard FAO methodology indicated near-optimal irrigation (ARIS of 0.98). Additionally,
the proposed methodology allows the estimation of the volume of applied water at the field scale. Comparisons between the
ARIS and IWP values obtained from actual applied water records against those calculated with the new methodology resulted
in good agreement. It is concluded that the integration of the METRIC method to calculate actual ET with a water balance model
allowed the determination of performance indicators in an irrigation scheme in a reliable and accurate fashion, requiring
only very limited information at the field level. 相似文献
299.
Javier García-Favre Ignacio F. López Lydia M. Cranston Daniel J. Donaghy Peter D. Kemp Iván P. Ordóñez 《Journal of Agronomy and Crop Science》2023,209(1):144-160
Lolium perenne L. (Lp) is the main pasture species in New Zealand, but climate change increases the likelihood of drought during summer and consequently lowers its growth rates. Bromus valdivianus Phil. (Bv) tolerates better the summer soil water restriction, but its competitiveness in a diverse pasture relates to the defoliation management and soil moisture levels. The performance of both species in terms of production, persistence and feed quality across seasons under different defoliation regimens was evaluated when the species were mixed and in monoculture. The treatments were applied in a randomised complete block design with three blocks. Bromus valdivianus and Lp monocultures and the 50/50 mixture (Mx) were grazed at low and high defoliation frequencies (i.e. based on Bv and Lp optimal leaf regrowth stage [LS], respectively). Herbage mass production was 15% higher in the Mx, mainly due to an increase in production in spring and summer. In spring, there was complementarity growth between the species, while during summer/early autumn, the Mx production relayed in the higher participation of Bv. Root biomass at depth (31–70 cm) was 38% greater for Bv monoculture and the Mx compared with Lp monoculture, which demonstrated the contribution of Bv to a better production of the mixture during and following the dry periods. In addition, the maintenance of the Bv tiller population and the higher growth rate during dry periods demonstrated its better fitness to low soil water availabilities than Lp. Although herbage mass was not modified by the defoliation frequency, forage quality of Bv showed values at low defoliation frequency that could compromise animal production during spring. However, there was an increase in root biomass under low defoliation frequencies, which suggested that a flexible grazing management across seasons would increase the niche utilisation between species in the mixture. The defoliation frequency of the mixture could be based on Lp LS during spring and winter, and slowed down, following Bv criteria, during summer and autumn. 相似文献
300.
Vernica Vieitez Victor Lpez-Rmis Rafael Barrera Ignacio A. Gmez de Segura 《Canadian journal of veterinary research》2022,86(1):40
The aim of this study was to evaluate the perioperative effects of robenacoxib on serum C-reactive protein (CRP) and iron concentrations in dogs undergoing gonadectomy. In a prospective, blinded, controlled clinical trial, 60 healthy dogs were randomly assigned to receive preoperative subcutaneous injection of either robenacoxib [2 mg/kg body weight (BW)], meloxicam (0.2 mg/kg BW), or saline (0.04 mL/kg BW), followed by oral administration over 72 h (robenacoxib: 2 to 4 mg/kg BW; meloxicam: 0.1 mg/kg BW; saline: gelatin capsules). Blood samples were taken before surgery and 12, 24, 48, 72 h, and 7 d after surgery. Pain scores were assessed via the short-form Glasgow Composite Pain Scale over 72 h postoperatively. C-reactive protein (CRP) and iron serum levels increased and decreased (P < 0.01, both), respectively, after surgery and returned to baseline within 1 wk. No differences were observed among treatments (P > 0.05) or based on surgery/gender (P > 0.05). Pain assessment revealed a higher incidence of treatment failure in saline (6 females versus 2 and 1 female in robenacoxib and meloxicam, respectively). In conclusion, robenacoxib and meloxicam had no influence on postoperative CRP or iron in dogs, which suggests that these nonsteroidal anti-inflammatory drugs (NSAIDs) do not have a relevant effect on these biomarkers. 相似文献