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111.
Johan ESPUNYES Emmanuel SERRANO Sara CHAVES Jordi BARTOLOM Pierre MENAUT Elena ALBANELL Pascal MARCHAND Kvin FOULCH Mathieu GAREL 《Integrative zoology》2022,17(1):78-92
Changes in vegetation phenology related to global warming are having alarming effects on the life history traits of many herbivore species. Such changes are particularly critical in alpine ecosystems, where strong climate limitations on plant growth make seasonal synchronization imperative for the growth, reproduction and survival of herbivores. However, despite the pivotal role of resource-use strategies on the performances of such species, few studies have explicitly assessed the mechanistic impact of climate change on their diets. We aimed to fill this gap by studying the effect of spring onset on the dietary composition and quality of a medium-size alpine herbivore while considering density-dependent processes and age- and sex-specific differences in foraging behavior. Using an exceptional, long-term (24 years) direct individual-based dietary monitoring of a Pyrenean chamois population (Rupicapra pyrenaica pyrenaica), we showed that ongoing earlier onsets of spring are leading to an earlier access to high-quality forage and therefore a higher diet quality at a fixed date, without apparent changes in diet composition. We also showed that at high densities, intraspecific competition reduced diet quality by driving animals to feed more on woody plants and less on nutritious forbs and graminoids. By assessing the mechanistic effects of global warming on the dietary patterns of species at the center of trophic networks, this study is an essential step for predictive models aiming at understanding the ongoing ecosystem consequences of the global climatic crisis. 相似文献
112.
Luciano Mateos David Lozano Oumar Abdoul Diallo Jordi Comas 《Agricultural Water Management》2010,97(6):901-1152
During the last quarter of the 20th century, many irrigation schemes were constructed along the bank of the Senegal River in Mauritania. About 40,000 ha were developed but less than 23,000 ha remain irrigated today. A program for rehabilitation is now in place to counteract deterioration and abandonment of these schemes. This paper presents an evaluation of the rehabilitation of a small, representative irrigation scheme governed by a farmers’ cooperative in the village of Bélinabé. Before rehabilitation, the scheme covered 37.7 ha comprising 107 plots each of 0.33 ha, essentially all devoted to production of rice. Water for irrigation was pumped directly from the river into two head basins and distributed through open canals. After rehabilitation, the scheme was extended to 115 ha with new plots averaging 0.36 ha. Water is now supplied by a single cluster of pumps and conveyed through pipes and open canals. Evaluation of performance consisted in analysis of: capacity; distribution losses; flexibility, adequacy and reliability of the system; maintenance status; farmer's perception of system performance. Field data were collected during irrigation campaigns before rehabilitation in 2004 and during 2006 and 2007 afterwards. A model of network distribution and field water balance was developed to assist evaluation. It was established that before rehabilitation the scheme could operate satisfactorily if proper maintenance were practiced. After rehabilitation, more families have access to irrigation but reliability and flexibility of water distribution have been reduced. Furthermore, pumping capacity is now insufficient to cover crop water requirements. Recommendations are provided for future rehabilitation work and maintenance of schemes generally. 相似文献
113.
Jordi Marsal G. Lopez J. del Campo M. Mata A. Arbones J. Girona 《Irrigation Science》2010,28(2):181-189
We examined, over the postharvest seasons of 2005–2007, regulated deficit irrigation (RDI) for its potential of saving water
and maintaining fruit yield and quality in ‘Summit’ sweet cherry. The postharvest irrigation treatments were: full irrigation
(Control), receiving 80% of water in Control (RDI-80%), and receiving 50% of water in Control (RDI-50%). Midday stem water
potential (Ψstem) was used for assessing plant water status. In 2006, trees produced a large crop and commercial fruit thinning had to be
applied, whereas 2007 was a low crop year. The RDI treatment, first applied in 2005, reduced fruit set in 2006 and also reduced
root winter starch concentration. In 2006, fruit set was lower in RDI-50% than in Control. But fruit thinning had still to
be done with the final yield being the same among treatments. In 2007, RDI-50% produced more fruit and higher yields than
Control. Relationship between postharvest Ψstem and crop load in the following season varied according to the year. They were negatively correlated in 2006 and positively
correlated in 2007. Fruit firmness did not vary with irrigation treatments in any of the years. Fruit soluble solid concentration
(SSC) and fruit relative dry matter (RDM) for RDI-50% was the highest in 2006 when RDI-50% trees had the lowest fruit set.
In 2007, SSC and RDM for RDI-50% were the lowest with the trees having the highest fruit set and crop load at harvest. This
study indicates that RDI-50% firstly applied in an “off” year, after crop has been harvested, can maintain fruit yield at
similar levels to fully irrigated trees while saving water by 45%. Correction of biennial bearing and partial saving of thinning
costs are additional advantages of this treatment. 相似文献
114.
Black currant fruits are recognized as being an important dietary source of health-related compounds, such as anthocyanins and ascorbic acid. In the present study, the biochemical composition (viz., nonstructural carbohydrates, individual anthocyanins, total anthocyanins, total phenolics, and organic acids, including ascorbic acid) from 17 UK-grown black currant cultivars was analyzed. Berry composition was significantly affected by genotype. Nonstructural carbohydrates ranged from 85.09 to 179.92 mg g(-1) on a fresh weight (FW) basis, while concentration for organic acids ranged from 36.56 to 73.35 mg g(-1) FW. Relative concentrations of cyanidin 3-glucoside, cyanidin 3-rutinoside, delphinidin 3-glucoside and delphinidin 3-rutinoside were 3.1-7.9%, 35.4-47.0%, 7.6-12.5% and 36.9-50.9%, respectively. Differences in the biochemical profile among cultivars were emphasized by principal component analysis (PCA) and hierarchical cluster analysis (HCA). PCA was able to discriminate between cultivars, especially on the basis of health-related compounds. Initial exploration revealed that individual anthocyanins, total phenolics, and ascorbic acid could be used to characterize and classify different cultivars. HCA showed that the biochemical composition of the different cultivars was related to parentage information. 相似文献
115.
Trond Bjørndal Jordi Guillen 《Aquaculture Economics & Management (Blackwell Science)》2013,17(4):433-451
ABSTRACTMarket integration occurs when prices among different locations or related goods follow similar patterns over time. Current knowledge on market integration between aquaculture and wild-caught fish is based on a small number of species and markets. Most studies show the existence of market integration between wild and farmed conspecifics, with the clear exception of European seabass and gilthead seabream in Southern European countries. In this study, we investigate whether this lack of market integration between wild and farmed conspecifics for European seabass and gilthead seabream in Southern European countries is specific for these species or is representative for the area. Therefore, we investigate the existence of market integration in Spain between wild and farmed conspecifics for a large variety of different species: turbot (Scophthalmus maximus), sole (Solea spp.), blackspot (red) seabream (Pagellus bogaraveo), Atlantic cod (Gadus morhua), and meagre (Argyrosomus regius). 相似文献
116.
Lorena Padilla Marina López-Arjona Silvia Martinez-Subiela Heriberto Rodriguez-Martinez Jordi Roca Isabel Barranco 《畜牧与生物技术杂志(英文版)》2022,(2):430-440
Background: Identification of relevant in vivo biomarkers for fertility remains a challenge for the livestock industry.Concentrations of the small peptide hormone oxytocin(OXT), involved in male reproductive function and present in the seminal plasma(SP) of several species could be a robust one. This study characterized concentrations of SPOXT in ejaculates from boars used in artificial insemination(AI) programs aiming to evaluate its relationship with sperm quality variables and in vivo fertili... 相似文献
117.
118.
Tuning of natural killer cell reactivity by NKp46 and Helios calibrates T cell responses 总被引:1,自引:0,他引:1
119.
Enrique L Michelotti José I Borrell Renee Roemmele Josep L Matallana Jordi Teixidó Lois M Bryman 《Journal of agricultural and food chemistry》2002,50(3):495-498
The preparation in multigram scale of two metabolites 3-(3,5-dichloro-4-methyl-benzoylamino)-2-hydroxy-3-methyl-pentanoic acid and 3-(3,5-dichloro-benzoylamino)-3-methyl-2-oxo-butyric acid isolated from soil treated with either Zoxium fungicide or Kerb herbicide was efficiently accomplished using a common 5-step synthetic process starting from easily available raw materials. 相似文献
120.
We investigated morphological evidence that might allow wild Pyrus spp. to be distinguished from cultivated material (Pyrus communis L.) in the North-eastern Iberian Peninsula. 134 pear trees were identified in the wild and characterized by 13 quantitative
and 13 qualitative leaf–shoot and fruit traits. The trees were visually classified into two preliminary groups of wild and
cultivated material and discriminant functions, based on a reference collection for allocating individuals to one of the groups,
were constructed. Both classifications were compared with a near-optimal numerical classification (the two-stage Ward-MLM
strategy) using two criteria. The visual assignment of trees allocated 60% of trees to the wild group and 40% to the cultivated
group. The overall discrepancy rate between the field classification and the discriminant analysis was low (17.4%). In general,
wild individuals had smaller leaves, shorter petioles and more rounded and smaller fruits than their cultivated counterparts.
They also had small-to-intermediate petiole widths, thorns on their shoots and straight or convex fruit profiles. However,
the Ward-MLM strategy always formed better groups, in terms of the two criteria used, in all the continuous and categorical
variables, for both leaf–shoot and fruit traits. Likewise, the agreement between classifications (discriminant analysis and
Ward-MLM strategy) was only partial, with some Ward-MLM groups composed of both wild and cultivated material in similar proportions.
This result suggests a limited success in identifying genuine wild individuals based on morphometric data, which can be ascribed
either to poor phenotypic diversity and lack of distinguishing traits among species or to widespread crossability and subsequent
development of hybrid/introgressant populations between wild and cultivated specimens. 相似文献