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61.
Etienne Neethling Théo Petitjean Hervé Quénol Gérard Barbeau 《Mitigation and Adaptation Strategies for Global Change》2017,22(5):777-803
Adaptation to climate change is a major challenge facing the viticulture sector. Temporally, adaptation strategies and policies have to address potential impacts in both the short- and long term, whereas spatially, place-based and context-specific adaptations are essential. To help inform decision-making on climate change adaptation, this study adopted a bottom-up approach to assess local climate vulnerability and winegrowers’ adaptive processes in two regulated wine-producing areas in the Anjou-Saumur wine growing sub-region, France. The data used for this study were collected through individual semi-structured interviews with 30 winegrowers. With a focus on wine quality, climate-related exposure, and sensitivity were dependent on many contextual factors (e.g., northern geographical position, wine regulatory frameworks, local environmental features) interacting with the regional oceanic climate. Climate and other non-climate-related variables brought about important changes in winegrowers’ management practices, varying in time and space. This ongoing process in decision-making enhanced winegrowers’ adaptive responses, which were primarily reactive (e.g., harvesting, winemaking) or anticipatory (e.g., canopy and soil management) to short-term climate conditions. Winegrowers described changing trends in climate- and grapevine (Vitis) -related variables, with the latter attributed to regional climate changes and evolving management practices. Regarding future climate trends, winegrowers’ displayed great uncertainty, placing the most urgent adaptation priority on short-term strategies, while changing grapevine varieties and using irrigation were identified as last resort strategies. The study concluded by discussing the implications of these findings in the context of climate change adaptation in viticulture. 相似文献
62.
Prévot-Julliard AC Clavel J Teillac-Deschamps P Julliard R 《Environmental management》2011,47(3):315-321
To garner support for biodiversity from the World’s human population, conservation biologists need an open-minded, integrated
conservation strategy. We suggest that this strategy should include efforts to (1) preserve existing high quality, diverse
ecosystems, (2) remediate impaired systems, (3) balance the needs of people and ecological resources, and (4) engender appreciation
of nature and its services. We refer to these four key tenets as reservation, restoration, reconciliation, and reconnection.
We illustrate these concepts by presenting the debate surrounding the management of exotic species from an unusual perspective,
the benefits of exotic species. By this example we hope to encourage an integrated approach to conservation in which management
strategies can be flexible, adjusting to society’s needs and the overall goals of conservation. 相似文献
63.
McQuaid N Zamyadi A Prévost M Bird DF Dorner S 《Journal of environmental monitoring : JEM》2011,13(2):455-463
The source water of a drinking water treatment plant prone to blooms, dominated by potential microcystin-producing cyanobacteria, was monitored for two seasons in 2007-2008. In the 2008 season, the median value for potential microcystin-producing cyanobacterial biovolume was 87% of the total phytoplankton biovolume in the untreated water of the plant. Depth profiles taken above the plant's intake identified three sampling days at high risk for the contamination of the plant's raw water with potentially toxic cyanobacteria. Chlorophyceae and Bacillariophyceae caused false positive values to be generated by the phycocyanin probe when cyanobacteria represented a small fraction of the total phytoplanktonic biovolume present. However, there was little interference with the phycocyanin probe readings by other algal species when potential microcystin-producing cyanobacteria dominated the phytoplankton of the plant's untreated water. A two-tiered method for source water monitoring, using in vivo phycocyanin fluorescence, is proposed based on (1) a significant relationship between in vivo phycocyanin fluorescence and cyanobacterial biovolume and (2) the calculated maximum potential microcystin concentration produced by dominant Microcystis sp. biovolume. This method monitors locally-generated threshold values for cyanobacterial biovolume and microcystin concentrations using in vivo phycocyanin fluorescence. 相似文献
64.
Carl Prày 《中国人口.资源与环境(英文版)》2007,5(2):53-62
China passed its Plant Variety Protection Act (PVPA) in 1997 which allowed us to do some initial testing of this proposition. We used a unique dataset on the applications of the new Plant Variety Protection (PVP), morphological characteristics, and institutional sources of all the important varieties of rice in three provinces of China to estimate the determinants of plant variety protection applications in China. The evidence suggests that both the government and private research programs are responding to economic and policy incentives and investing in plant variety protection as economists would expect profit maximizing firms to invest. The discussion of the evolution of the seed industry suggested that the combination of the new seed law in 2000 and the new plant variety protection regulation had changed the structure of the seed industry and provided an important incentive to invest in PVPs both by public research institutes and commercial firms. Finally, there is some preliminary evidence that private firms have smaller incentives to develop new varieties than to purchase the new varieties. 相似文献
65.
The aim of this study was analyze reproductive performance of wild boar in different habitat over a 7-year period (2006–2012). A total of 468 pregnant females and 2.819 fetuses were analyzed, the mean number of fetuses was 6.02 (median = 6) per animal (4.62 per juvenile, 6.39 per yearling and 6.77 per adult). In litters, male-biased fetuses occurred significantly more often than female, the overall fetal sex ratio is 1: 0.86. Positive reproductive traits increased up to 90 kg of live body weight and then decreased. The reproductive parameters observed in our study reflect a relatively high reproductive capacity compared to the populations in southern and northern Europe, but are comparable with some populations in central Europe. Concerning habitat conditions, it is obvious that they influence the reproductive performance of females, and therefore must be included in management plans. 相似文献
66.
Marcela Nováková Barbora Vašáková Hana Kutalová Katarina Galeštoková Klára Průšová Petr Šmilauer Radim Šumbera Daniel Frynta 《Behavioral ecology and sociobiology》2010,64(3):371-379
Spiny mice of the genus Acomys (Muridae) represent a very suitable mammalian model for studying factors influencing the secondary sex ratio (SSR). The maternal
effort in these rodents is extremely biased in favour of the prenatal period and, therefore, maternal manipulation of the
SSR is potentially more advantageous. We studied the SSR in four populations/species of spiny mice kept in family groups consisting
of two closely related females, one non-relative male and their descendants. The groups were established from founding animals
aged about 3 months (maturing age) and were allowed to breed freely for several months. Each litter was sexed after birth,
and relevant data were thoroughly recorded. Altogether, data were collected on 1684 litters: 189 of Acomys sp. from Iran, 203 of A. cilicicus, 875 of A. cahirinus, and 417 of A. dimidiatus. We recorded the sex of 4048 newborns of which 1995 were males and 2053 were females. The overall sex ratio was close to
1:1 (49.2%). Generalized linear mixed models and/or generalized linear models were constructed to evaluate the effect of four
life history and eight social variables on the sex ratio. No consistent effects of these variables on the sex ratio were found
and, interestingly, none of the variables associated with maternal life history had any effect on the sex ratio. Three factors
associated with group composition (i.e. the number of immature males, the number of immature females and the number of breeding
females) did have significant effects on the sex ratio, but these effects were not consistent across the studied species.
In conclusion, our evaluation of this large dataset revealed that the sex ratio in spiny mice is surprisingly stable. 相似文献
67.
Thomas Merkling Lena Agdere Elise Albert Romain Durieux Scott A. Hatch Etienne Danchin Pierrick Blanchard 《Behavioral ecology and sociobiology》2014,68(2):309-319
In unpredictable environments, any tactic that enables avian parents to adjust brood size and, thus, energy expenditure to environmental conditions should be favoured. Hatching asynchrony (HA), which occurs whenever incubation commences before clutch completion, may comprise such a tactic. For instance, the sibling rivalry hypothesis states that the hierarchy among chicks, concomitant to HA, should both facilitate the adjustment of brood size to environmental conditions and reduce several components of sibling competition as compared to synchronous hatching, at both brood and individual levels. We thus predicted that brood aggression, begging and feeding rates should decrease and that older chick superiority should increase with HA increasing, leading to higher growth and survival rates. Accordingly, we investigated the effects of an experimental upward and downward manipulation of HA magnitude on behaviour, growth and survival of black-legged kittiwake (Rissa tridactyla) chicks. In line with the sibling rivalry hypothesis, synchronous hatching increased aggression and tended to increase feeding rates by parents at the brood level. Begging rates, however, increased with HA contrary to our expectations. At the individual level, as HA magnitude increased, the younger chick was attacked and begged proportionally more often, experienced a slower growth and a higher mortality than its sibling. Overall, the occurrence of energetic costs triggered by synchronous hatching both for parents and chicks, together with the lower growth rate and increased mortality of the younger chick in highly asynchronous broods suggest that natural HA magnitude may be optimal. 相似文献
68.
69.
Growth of alfalfa in sludge-amended soils and inoculated with rhizobia produced in sludge 总被引:1,自引:0,他引:1
The efficiency of rhizobial inoculants produced in wastewater sludge used as a growth medium and as a carrier was compared with that of inoculants produced in yeast mannitol broth (YMB) medium and by using peat as a carrier. Alfalfa (Medicago sativa L.) plants were inoculated with solid and liquid Sinorhizobium meliloti inoculants and grown in pots containing two soil types (Kamouraska clay soil and Saint-André sandy soil). The effect of various levels of sludge amendment (60 and 120 kg N/ha) and nitrogen fertilizer (60 kg N/ ha) was also studied. The sludge-based inoculants showed the same symbiotic efficiency (nodulation and plant yield) as YMB-based inoculants. The inoculation increased the nodulation indexes from 4-6 to 8-12, and the rhizobial number from 10(3) (uninoculated soils) to 10(6)-10(7) cells/g in inoculated soils. However, the shoot dry weights and the nitrogen contents were not increased significantly by the inoculation. Applying sludge as an amendment enhanced the rhizobial number in soils from 10(3) to 10(4) cells/g and improved significantly the plant growth (shoot dry weights and nitrogen contents). This improvement increased with sludge rate and with the cut (three cuts). Compared with sludge, N fertilizer gave lower plant yields. The nodulation was not affected by sludge and N-fertilizer application. The texture and physico-chemical properties of soil were found to affect the yield and nitrogen content of the plants. In this study, macroelements and heavy metals were at acceptable levels and were not considered to be negative factors. 相似文献
70.
Effects of light intensity and nutrient availability on diel patterns of cell metabolism and growth in populations of Synechococcus spp. 总被引:2,自引:0,他引:2
Between July 21 and August 8, 1984, phytoplankton were collected from the surface (2 m) and/or chlorophyll maximum of a neritic front, warm-core eddy 84-E and Wilkinson's Basin in the Northwest Atlantic Ocean and incubated up to 38 h in 200-liter vats. Effects of light intensity and nutrient availability on diel patterns of cell metabolism were analyzed in a 0.6- to 1-m fraction, where Synechococcus spp. represented 80 to 100% of the total photoautotrophs. Populations held under in situ conditions exhibited daytime peaks in photosynthetic potential (Pmax) that were an order of magnitude higher than nighttime Pmax values. Daytime phasing of Pmax peaks had no relationship to asynchronous fluctuations in cellular activities of ribulose 1,5 bisphosphate carboxylase (RUBPCase) or phosphoenol pyruvate carboxylase (PEPCase), or to variations in chlorophyll content. Daytime Pmax peaks were about 12 h out of phase with nighttime maxima in the frequency of dividing cells (FDC). The phase relationship between Pmax and FDC could be altered by manipulating environmental conditions. High light exposure of depp populations did not affect timing of the Pmax peak, but its magnitude increased and coincided with increased RUBPCase activity and chlorophyll photobleaching. In the eddy population, a major shift in the timing of peak Pmax was induced when increased light intensity was accompanied by nutrient enrichment. This change coincided with major increases in cellular chlorophyll and carboxylating enzyme activity. Lowering irradiance and/or increasing nutrient availability elicited different diel pattern in cellular metabolism in surface populations from the eddy and from Wilkinson's Basin that appeared linked to differences in the nutrient status of the cells. Rates of cell division estimated from the percentage of dividing cells in preserved samples were 0.83 divisions d-1 in surface warm-core eddy populations, supporting the view that carbon and nitrogen turnover rates in oligotrophic waters can be sufficient to promote near optimal growth of Synechococcus spp. 相似文献