Description of a new procedure to estimate the carbon stocks of all forest pools and impact assessment of methodological choices on the estimates     

Nicolas Latte  Gilles Colinet  Adeline Fayolle  Philippe Lejeune  Jacques Hébert  Hugues Claessens  Sébastien Bauwens 《European Journal of Forest Research》2013,132(4):565-577

Forest ecosystems play a major role in atmospheric carbon sequestration and emission. Comparable organic carbon stock estimates at temporal and spatial scales for all forest pools are needed for scientific investigations and political purposes. Therefore, we developed a new carbon stock (CS) estimation procedure that combines forest inventory and soil and litter geodatabases at a regional scale (southern Belgium). This procedure can be implemented in other regions and countries on condition that available external carbon soil and litter data can be linked to forest inventory plots. The presented procedure includes a specific CS estimation method for each of the following forest pools and subpools (in brackets): living biomass (aboveground and belowground), deadwood (dead trees and snags, coarse woody debris and stumps), litter, and soil. The total CS of the forest was estimated at 86 Tg (185 Mg ha^?1). Soil up to 0.2 m depth, living biomass, litter, and deadwood CSs account, respectively, for 48, 47, 4, and 1 % of the total CS. The analysis of the CS variation within the pools across ecoregions and forest types revealed in particular that: (1) the living biomass CS of broadleaved forests exceeds that of coniferous forests, (2) the soil and litter CSs of coniferous forest exceed those of broadleaved forests, and (3) beech stands come at the top in carbon stocking capacity. Because our estimates differ sometimes significantly from the previous studies, we compared different methods and their impacts on the estimates. We demonstrated that estimates may vary highly, from ?16 to +12 %, depending on the selected methods. Methodological choices are thus essential especially for estimating CO₂ fluxes by the stock change approach. The sources of error and the accuracy of the estimates were discussed extensively.  相似文献   

Natural enemies of the South American moth, Tuta absoluta, in Europe, North Africa and Middle East, and their potential use in pest control strategies   总被引：1，自引：0，他引：1  

Lucia Zappalà  Antonio Biondi  Alberto Alma  Ibrahim J. Al-Jboory  Judit Arnò  Ahmet Bayram  Anaïs Chailleux  Ashraf El-Arnaouty  Dan Gerling  Yamina Guenaoui  Liora Shaltiel-Harpaz  Gaetano Siscaro  Menelaos Stavrinides  Luciana Tavella  Rosa Vercher Aznar  Alberto Urbaneja  Nicolas Desneux 《Journal of pest science》2013,86(4):635-647

The South American tomato leafminer, Tuta absoluta Meyrick (Lepidoptera: Gelechiidae), is an invasive Neotropical pest. After its first detection in Europe, it rapidly invaded more than 30 Western Palaearctic countries becoming a serious agricultural threat to tomato production in both protected and open-field crops. Among the pest control tactics against exotic pests, biological control using indigenous natural enemies is one of the most promising. Here, available data on the Afro-Eurasian natural enemies of T. absoluta are compiled. Then, their potential for inclusion in sustainable pest control packages is discussed providing relevant examples. Collections were conducted in 12 countries, both in open-field and protected susceptible crops, as well as in wild flora and/or using infested sentinel plants. More than 70 arthropod species, 20 % predators and 80 % parasitoids, were recorded attacking the new pest so far. Among the recovered indigenous natural enemies, only few parasitoid species, namely, some eulophid and braconid wasps, and especially mirid predators, have promising potential to be included in effective and environmentally friendly management strategies for the pest in the newly invaded areas. Finally, a brief outlook of the future research and applications of indigenous T. absoluta biological control agents are provided.  相似文献   

Genotype by climate interaction in the genetic evaluation for growing traits of Braunvieh cattle in Mexico     

Luis A. Saavedra-Jiménez  Rodolfo Ramírez-Valverde  Rafael Núñez-Domínguez  José G. García-Muñiz  Nicolas Lopez-Villalobos  Agustín Ruíz-Flores 《Tropical animal health and production》2013,45(7):1489-1494

The objective of this study was to determine the magnitude of genotype by climate interaction (GCI) in the national genetic evaluation for weaning (WW) and yearling (YW) weights of Mexican Braunvieh cattle. The numbers of performance records and animals in the pedigree were 12,364 and 25,173 for WW, and 7,991 and 18,072 for YW, respectively. Performance records were clustered based on climatological variables into: dry tropic (DT), wet tropic (WT), and temperate (TE) climates. Animal models were used to estimate genetic parameters and predict breeding values in each of the climates. Bivariate analyses were carried out for pairwise combinations of climates on each trait, considering the same trait in different climates as a different trait. Criteria to evaluate GCI were genetic correlations (r _g), correlations between predicted breeding values (r _BV), and frequencies of coincidence (FC) in the ranking of the top 25 sires. Results of comparisons between pairs of climates were variable, depending on specific cases. For WW, the r _g, r _BV, and FC ranged from ?0.36 to 0.84, ?0.60 to 0.97, and 0.16 to 0.92, respectively; whereas for YW, they fluctuated between 0.23 and 0.99, 0.33 and 1.00, and 0.60 and 1.00, respectively. For both traits, the results suggest absence of GCI between DT and TE; however, GCI was detected in the other pairs of climates, where WT was involved. To maximize genetic progress, the joint genetic evaluation should be performed only for animals with performance data in DT and TE, whereas a separated evaluation is suggested for animals with performance records generated under WT conditions.  相似文献   

Population structure of the fish pathogen Flavobacterium psychrophilum at whole-country and model river levels in Japan     

Erina Fujiwara-Nagata  Céline Chantry-Darmon  Jean-Fran?ois Bernardet  Mitsuru Eguchi  Eric Duchaud  Pierre Nicolas 《Veterinary research》2013,44(1):34

The bacterium Flavobacterium psychrophilum is a serious problem for salmonid farming worldwide. This study investigates by multilocus sequence typing (MLST) the population structure of this pathogen in Japan where it is also a major concern for ayu, a popular game fish related to salmoniforms. A total of 34 isolates collected across the country and 80 isolates sampled in a single model river by electrofishing were genotyped. The data accounting for 15 fish species allowed identifying 35 distinct sequence types (ST) in Japan. These ST are distinct from those reported elsewhere, except for some ST found in rainbow trout and coho salmon, two fish that have been the subject of intensive international trade. The pattern of polymorphism is, however, strikingly similar across geographical scales (model river, Japan, world) in terms of the fraction of molecular variance linked to the fish host (~50%) and of pairwise nucleotide diversity between ST (~5 Kbp^-1). These observations go against the hypothesis of a recent introduction of F. psychrophilum in Japan. Two findings were made that are important for disease control: 1) at least two independent F. psychrophilum lineages infect ayu and 2) co-infections of the same individual fish by different strains occur.  相似文献   

Dynamics of influenza A virus infections in permanently infected pig farms: evidence of recurrent infections,circulation of several swine influenza viruses and reassortment events     

Nicolas Rose  Séverine Hervé  Eric Eveno  Nicolas Barbier  Florent Eono  Virginie Dorenlor  Mathieu Andraud  Claire Camsusou  Fran?ois Madec  Ga?lle Simon 《Veterinary research》2013,44(1):72

Concomitant infections by different influenza A virus subtypes within pig farms increase the risk of new reassortant virus emergence. The aims of this study were to characterize the epidemiology of recurrent swine influenza virus infections and identify their main determinants. A follow-up study was carried out in 3 selected farms known to be affected by repeated influenza infections. Three batches of pigs were followed within each farm from birth to slaughter through a representative sample of 40 piglets per batch. Piglets were monitored individually on a monthly basis for serology and clinical parameters. When a flu outbreak occurred, daily virological and clinical investigations were carried out for two weeks. Influenza outbreaks, confirmed by influenza A virus detection, were reported at least once in each batch. These outbreaks occurred at a constant age within farms and were correlated with an increased frequency of sneezing and coughing fits. H1N1 and H1N2 viruses from European enzootic subtypes and reassortants between viruses from these lineages were consecutively and sometimes simultaneously identified depending on the batch, suggesting virus co-circulations at the farm, batch and sometimes individual levels. The estimated reproduction ratio R of influenza outbreaks ranged between 2.5 [1.9-2.9] and 6.9 [4.1-10.5] according to the age at infection-time and serological status of infected piglets. Duration of shedding was influenced by the age at infection time, the serological status of the dam and mingling practices. An impaired humoral response was identified in piglets infected at a time when they still presented maternally-derived antibodies.  相似文献   

Towards a better understanding of Rift Valley fever epidemiology in the south-west of the Indian Ocean     

Thomas Balenghien  Eric Cardinale  Véronique Chevalier  Nohal Elissa  Anna-Bella Failloux  Thiery Nirina Jean Jose Nipomichene  Gaelle Nicolas  Vincent Michel Rakotoharinome  Matthieu Roger  Betty Zumbo 《Veterinary research》2013,44(1):78

Rift Valley fever virus (Phlebovirus, Bunyaviridae) is an arbovirus causing intermittent epizootics and sporadic epidemics primarily in East Africa. Infection causes severe and often fatal illness in young sheep, goats and cattle. Domestic animals and humans can be contaminated by close contact with infectious tissues or through mosquito infectious bites. Rift Valley fever virus was historically restricted to sub-Saharan countries. The probability of Rift Valley fever emerging in virgin areas is likely to be increasing. Its geographical range has extended over the past years. As a recent example, autochthonous cases of Rift Valley fever were recorded in 2007–2008 in Mayotte in the Indian Ocean. It has been proposed that a single infected animal that enters a naive country is sufficient to initiate a major outbreak before Rift Valley fever virus would ever be detected. Unless vaccines are available and widely used to limit its expansion, Rift Valley fever will continue to be a critical issue for human and animal health in the region of the Indian Ocean.  相似文献   

Invasion biology of spotted wing Drosophila (Drosophila suzukii): a global perspective and future priorities     

Mark K. Asplen  Gianfranco Anfora  Antonio Biondi  Deuk-Soo Choi  Dong Chu  Kent M. Daane  Patricia Gibert  Andrew P. Gutierrez  Kim A. Hoelmer  William D. Hutchison  Rufus Isaacs  Zhi-Lin Jiang  Zsolt Kárpáti  Masahito T. Kimura  Marta Pascual  Christopher R. Philips  Christophe Plantamp  Luigi Ponti  Gábor Vétek  Heidrun Vogt  Vaughn M. Walton  Yi Yu  Lucia Zappalà  Nicolas Desneux 《Journal of pest science》2015,88(3):469-494

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Lipid deposition on the tongue after oral processing of medium-chain triglycerides and impact on the perception of mouthfeel     

Pivk U  Godinot N  Keller C  Antille N  Juillerat MA  Raspor P 《Journal of agricultural and food chemistry》2008,56(3):1058-1064

Lipids between the tongue and palate strongly contribute to the sensory impact of a product. Mouthfeel is a sensory attribute responsible for distinguishing reduced fat from full fat food products. The aim of this work was to quantify the distribution, deposition, and retention of lipids on the tongue and palate upon oral processing and relate this to texture. The thickness of lipid deposition was measured in mouth by fluorescence. A trained panel evaluated the perceived intensity of samples to describe lipid Mouthfeel. The thickness of lipid deposition on the tongue shows spatial variation (10-100 microm) and stopped increasing after intakes higher than 8 mL of medium-chain triglycerides (MCTs). After 2 min, only 25% of the lipid deposition was retained on oral surfaces. A difference in the thickness of lipid deposition of 25 microm resulted in significantly different perception. This work describes the in-mouth behavior of food lipids and its influence on texture perception.  相似文献   

Arsenic Concentration in Tobacco Leaves: A Study on Three Commercially Important Tobacco (Nicotiana tabacum L.) Types     

Nicolas Lugon-Moulin  Florian Martin  Marc R. Krauss  Patrice B. Ramey  Luca Rossi 《Water, air, and soil pollution》2008,192(1-4):315-319

In recent years, arsenic (As) has received increased attention as humans may be exposed to it through occupational and environmental exposure. Tobacco (Nicotiana tabacum L.) like other crops can uptake this element from the soil, which may lead to human exposure. Here, we report on a survey on arsenic in cured or processed tobacco leaves obtained from Africa, Asia, Europe, South and North America. A total of 1,431 leaf samples of flue-cured, burley, and Oriental tobaccos were obtained from various sampling locations during 2002 to 2004. Arsenic concentration in the samples averaged 0.4?±?0.6 μg g^?1 as determined by inductively coupled plasma-mass spectrometry. Recorded values from most samples showed that concentrations of arsenic were usually found at the lower end of the distribution. Significant differences were found among tobacco types, sampling locations, and crop years. Arsenic concentrations were rather low in the majority of regions investigated, which is compatible with data from the literature. However, sample size was small and sampling geographically restricted. Our results would need to be validated with a larger dataset.  相似文献   

Above-ground earthworm casts affect water runoff and soil erosion in Northern Vietnam   总被引：1，自引：0，他引：1  

Pascal Jouquet  Pascal Podwojewski  Nicolas Bottinelli  Jérôme Mathieu  Maigualida Ricoy  Didier Orange  Toan Duc Tran  Christian Valentin 《CATENA》2008

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