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981.
- The delimitation of conservation units may be supported by information on compositional (taxonomic), functional, and phylogenetic diversity of a given locality or region. In this context, systematic conservation planning and key biodiversity areas are promising approaches for biodiversity protection.
- Factors such as species representativeness and exclusivity may be used to identify geographical distribution patterns and select relevant areas for conservation at a local scale.
- This study aims to identify areas with rare and restricted fish species in mountain streams in Southern Brazil, using a method that unites ecological and biogeographical approaches.
- Seven river basins and 152 mountain streams in Southern Brazil were sampled to obtain data on the occurrence and abundance of 115 fish species. The rarity status of each species was determined and endemicity analysis was used to find areas of restricted species (ARS) with three cell sizes.
- Using larger cells, continuous areas were identified and supported by a higher proportion of rare fish species. Using smaller cells, discontinuous areas were identified within each of the river basins, where rare and endemic fish species occur. Most of the smaller areas relevant for protecting fish fauna were located outside of conservation units.
- Fundamental areas were selected for the protection of fish species in mountain streams in Southern Brazil. Both the method proposed and the areas with rare and restricted fish species identified may be used to support systematic conservation planning and to delimit new priority areas for conservation.
982.
In this study, an artificial neural network (ANN) and a statistical model are developed to predict the unevenness of polyester/viscose
blended open-end rotor spun yarns. Seven different blend ratios of polyester/viscose slivers are produced and these slivers
are manufactured with four different rotor speed and four different yarn counts in rotor spinning machine. A back propagation
multi layer perceptron (MLP) network and a mixture process crossed regression model (simplex lattice design) with two mixture
components (polyester and viscose blend ratios) and two process variables (yarn count and rotor speed) are developed to predict
the unevenness of polyester/viscose blended open-end rotor spun yarns. Both ANN and simplex lattice design have given satisfactory
predictions, however, the predictions of statistical models gave more reliable results than ANN. 相似文献
983.
The development, longevity, fecundity and life-table parameters of the endoparasitoid Anagyrus pseudococci (Girault) (Hymenoptera: Encyrtidae), 15 d.o. (3rd-instar nymphs) and 21 d.o. (young adult females) of the vine mealybug,
Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae) at 28 ± 1°C, 65 ± 10%RH and 16:8h L:D under laboratory conditions. The developmental
time of female parasitoids within the host was 17.7 ± 0.39 days in 15 d.o. and 16.65 ± 0.25 days in 21 d.o. hosts; for males,
development time was 16.85 ± 0.29 and 15.25 ± 0.09 days, respectively. The average number of offspring per female was 22.35 ± 1.68
in 15 d.o. and 34.8 ± 2.56 in 21 d.o. vine mealybugs. The longevity of female parasitoids was 14.8 ± 0.98 days in 15 d.o.
and 15.65 ± 0.92 days in 21 d.o. mealybugs, respectively; for males, longevity was determined as 7.3 ± 0.43 and 6.7 ± 0.54 days,
respectively. The mean time of pupation was 7.85 ± 0.003 days in 15 d.o. mealybugs and 8.65 ± 0.003 days in 21 d.o. mealybugs.
The aggregate encapsulation rate in the parasitized 15 d.o. mealybugs was 49.73 and 60.36% in 21 d.o. mealybugs. Furthermore,
effective encapsulation was 24.82% in 15 d.o. mealybugs and 37.50% in 21 d.o. mealybugs. Population growth rate (r
m) for A. pseudococci was 0.0999 female/female/days in 15 d.o. mealybugs and 0.1269 female/female/days in 21 d.o. mealybugs. The mean population
generation time was 23.49 days for parasitoids reared in 15-days-old and 22.39 days when reared in 21 d.o. mealybugs. 相似文献
984.
Ramazan Özçelik Yasin Karatepe Nevzat Gürlevik Isabel Cañellas Felipe Crecente-Campo 《林业研究》2016,27(1):101-117
Estimating individual tree volume is one of the essential building blocks in forest growth and yield models.Ecologically based taper equations provide accurate volume predictions and allow classification by merchantable sizes, assisting in sustainable forest management.In the present study, ecoregion-based compatible volume systems for brutian pine and black pine in the three ecoregions of southern Turkey were developed. Several well-known taper functions were evaluated. A secondorder continuous-time autoregressive error structure was used to correct the inherent autocorrelation in the hierarchical data, allowing the model to be applied to irregularly spaced and unbalanced data. The compatible segmented model of Fang et al.(For Sci 46:1–12, 2000) best described the experimental data. It is therefore recommended for estimating diameter at a specific height, height to a specific diameter, merchantable volume, and total volume for the three ecoregions and two species analyzed. The nonlinearextra sum of squares method indicated differences in ecoregion and tree-specific taper functions. A different taper function should therefore be used for each pine species and ecoregion in southern Turkey. Using ecoregionspecific taper equations allows making more robust estimations and, therefore, will enhance the accuracy of diameter at different heights and volume predictions. 相似文献
985.
Felipe Anderson Pereira Natalia Ha André Fernando Nascimento Gonçalves Hélio Antunes Wagner C. Valenti Thiago El Hadi Perez Fabregat 《Aquaculture International》2018,26(2):487-493
The objective of this study was to determine if the South American catfish (Rhamdia quelen) is suitable to be farmed in polyculture with rainbow trout (Oncorhynchus mykiss) in intensive systems during the juvenile phase to maximize feed efficiency. Juveniles of rainbow trout (3.94?±?0.11 g) and South American catfish (2.07?±?0.04 g) were distributed in 16 tanks (100 L) with continuous water renewal at the density of 50 fish/tank. The experimental design was completely randomized with four treatments (proportions between species) and four replicates. The treatments were 100% trout (100T), 70% trout and 30% catfish (70T30C), 50% trout and 50% catfish (50T50C), and 100% catfish (100C). Fish were fed twice daily with pelleted commercial feed (45% crude protein) during an experimental period of 56 days. No feed was provided for the catfish in polyculture. The weight gained by the trout was higher in polyculture. Fish survival did not differ among the treatments. The average survival of the trout in all tanks was 99.6?±?1.0%, while the survival of the South American catfish was 97.9?±?2.7%. The total feed conversion ratio was lower in the 70T30J treatment, followed by the 100T treatment. Rainbow trout and South American catfish are compatible species for farming together in the first phase of their juvenile development. The different spaces occupied by these species inside tanks probably prevent competition or agonistic behavior. Catfish eat the non-ingested leftover diet from the trout, which improves feed conversion and increases sustainability. 相似文献
986.
Sara El Kadili Marianne Raes Jean‐Loup Bister Jean‐Franois Beckers Gaston Amzati Bouchaib Archa Mouad Chentouf Nathalie Kirschvink 《Reproduction in domestic animals》2019,54(7):1003-1009
The efficacy of eight combinations of fluorogestone acetate (FGA, 20 or 40 mg as intravaginal device during 11 days), equine chorionic gonadotropin (eCG, 300 or 500 UI injected 48 hr before FGA removal) and prostaglandin F2α (cloprostenol, 0 or 50 μg injected 48 hr before FGA removal) aiming at induction and synchronization of oestrus and ovulation was evaluated during the anoestrus season in spring and during the breeding season in autumn in adult Beni Arouss goats. Oestrous behaviour was recorded between 12 and 60 hr after FGA removal. Blood samplings allowing to assess onset of the pre‐ovulatory LH surge and increase of progesterone as sign of an active corpus luteum were performed, respectively, between 20 and 60 hr and 3, 5, 8 and 15 days after FGA removal. No season‐related differences (spring vs. autumn) were observed for oestrous response (95% vs. 93%), pre‐ovulatory LH surge (94% vs. 84%) and luteal response after 3–8 and 11–15 days post‐treatment (respectively 92% vs. 66% and 92% vs. 98%). The onset of oestrus (21 [13–53] vs. 32 [12–54] hr) and LH surge (26 [20–60] vs. 38 [22–60] hr) occurred significantly later in autumn. FGA (40 vs. 20 mg) in autumn significantly delayed the onset of oestrus (36 [16–54] vs. 23 [12–47] hr) and LH surge (44 [26–58] vs. 33 [22–60] hr). Significant treatment‐related differences were recorded for onset of LH surge (earliest for 20 mg FGA, 300 IU eCG, 50 μg PGF2α) and onset of luteal phase (latest for 40 mg FGA, 300 IU eCG, 50 μg PGF2α). In conclusion, the hormone combinations tested appeared equally effective in terms of oestrous and ovulation rates. Season has influenced significantly the onset of oestrus and LH surge, and the high dose regimen of FGA delayed the ovarian response in autumn. 相似文献
987.
Avelino J Cabut S Barboza B Barquero M Alfaro R Esquivel C Durand JF Cilas C 《Phytopathology》2007,97(12):1532-1542
ABSTRACT We monitored the development of American leaf spot of coffee, a disease caused by the gemmiferous fungus Mycena citricolor, in 57 plots in Costa Rica for 1 or 2 years in order to gain a clearer understanding of conditions conducive to the disease and improve its control. During the investigation, characteristics of the coffee trees, crop management, and the environment were recorded. For the analyses, we used partial least-squares regression via the spline functions (PLSS), which is a nonlinear extension to partial least-squares regression (PLS). The fungus developed well in areas located between approximately 1,100 and 1,550 m above sea level. Slopes were conducive to its development, but eastern-facing slopes were less affected than the others, probably because they were more exposed to sunlight, especially in the rainy season. The distance between planting rows, the shade percentage, coffee tree height, the type of shade, and the pruning system explained disease intensity due to their effects on coffee tree shading and, possibly, on the humidity conditions in the plot. Forest trees and fruit trees intercropped with coffee provided particularly propitious conditions. Apparently, fertilization was unfavorable for the disease, probably due to dilution phenomena associated with faster coffee tree growth. Finally, series of wet spells interspersed with dry spells, which were frequent in the middle of the rainy season, were critical for the disease, probably because they affected the production and release of gemmae and their viability. These results could be used to draw up a map of epidemic risks taking topographical factors into account. To reduce those risks and improve chemical control, our results suggested that farmers should space planting rows further apart, maintain light shading in the plantation, and prune their coffee trees. 相似文献
988.
Marie-Agnès Jacques Nathaëlle Luçon Sandrine Houdault 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(4):695-700
Bacterial blight of garlic, caused by Pseudomonas salomonii, results in leaf and sheath necrosis and sometimes leads to soft rot and plant death. The epidemiology of this bacterial
disease, known as ‘Café au lait’ disease, is poorly understood and no resistant cultivars are currently available. To develop
control strategies for this disease, we investigated principal sources of inoculum. The pathogen was isolated from bulbs from
plants with typical vegetative symptoms of bacterial blight. Subsequent development of typical foliar symptoms on plantlets
originating from symptomatic bulbs demonstrated transmission of the pathogen in the planting material. In one of three field
experiments the contamination rate of planting stock influenced the disease incidence in field-grown garlic. The importance
of planting stock as a source of inoculum was demonstrated here and should be evaluated relative to other potential sources
such as crop debris, soil or alternate hosts in order to develop successful control strategies. 相似文献
989.
Vansnick E de Rijk P Vercammen F Rigouts L Portaels F Geysen D 《Veterinary microbiology》2007,122(1-2):166-171
Culturing of Mycobacterium avium subspecies paratuberculosis (Map) remains difficult and is time consuming. An alternative for the rapid detection of Map in samples is PCR. We have developed a sensitive DNA-extraction method based on sequence capture for the rapid detection of M. avium subspecies paratuberculosis by PCR in fecal and tissue samples. The method detected 10(2)Map/g feces using spiked samples, and reached a diagnostic sensitivity of 33,7% compared to 22% for culture. Analysis of tissue samples gave 65 polymerase chain reaction (PCR)-positive (42.2%) and 49 culture-positive samples (31.8%). Therefore, the detection limit of the DNA-extraction is the same as previously reported for culture, the PCR assay could detect more positive samples than the culture method. 相似文献
990.