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71.
Concepts and methods for landscape multifunctionality and a unifying framework based on ecosystem services 总被引:2,自引:0,他引:2
Matias E. Mastrangelo Federico Weyland Sebastian H. Villarino María P. Barral Laura Nahuelhual Pedro Laterra 《Landscape Ecology》2014,29(2):345-358
The potential of landscapes to supply multiple benefits to society beyond commodities production has received increasing research and policy attention. Linking the concept of multifunctionality with the ecosystem services (ES) approach offers a promising avenue for producing scientific evidence to inform landscape planning, e.g., about the relative utility of land-sharing and land-sparing. However, the value for decision-making of ES-based multifunctionality assessments has been constrained by a significant conceptual and methodological dispersion. To contribute towards a cohesive framework for landscape multifunctionality, we analyse case studies of joint ES supply regarding ten criteria designed to ultimately answer four aspects: (i) the multifunctionality of what (e.g., landscapes), (ii) the type of multifunctionality (e.g., based on ES synergies), (iii) the procedure of multifunctionality assessments, and (iv) the purpose of multifunctionality. We constructed a typology of methodological approaches based on scores for criteria describing the evaluation method and the level of stakeholder participation in assessments of joint ES supply. Surveyed studies and underlying types of methodological approaches (spatial, socio-spatial, functional, spatio-functional) differed in most criteria. We illustrate the influence of methodological divergence on planning recommendations by comparing two studies employing contrasting approaches (spatial and functional) to assess the joint supply of wildlife habitat and agricultural production in the Argentine Chaco. We distinguish between a pattern-based and process-based multifunctionality, where the latter can only be detected through approaches considering the ecological processes (e.g., ES complementarities) supporting the supply of multiple ES (functional and spatio-functional). Finally, we propose an integrated approach for assessing a socially-relevant process-based multifunctionality. 相似文献
72.
Francisco Javier Estay Rodrigo Noriega Jose Pedro Ureta Werner Martín & Nelson Colihueque 《Aquaculture Research》2004,35(5):447-452
Data on reproductive traits in a cultured population of brown trout (Salmo trutta L.) in southern Chile were collected over three consecutive reproductive seasons: 1999, 2000 and 2001, corresponding to the first (at 3 years), second and third spawnings in females. Data were collected from individual females (n=238, 273 and 169 respectively). The reproductive season lasted mainly from June to August. The peak (July) tended to increase with each season (55.46%, 62.27% and 80.81% of total spawning fish respectively). Female body weight (470.8±102.5, 735.0±150 and 1263.9±263.4 g), total fecundity (1182±344, 1904±595 and 2744±605) and egg diameter (4.64±0.11, 4.67±0.27 and 5.24±0.12 mm) increased significantly (P<0.01) over successive reproductive seasons, particularly between the second and third spawnings. Relative fecundity, on the other hand, decreased significantly with each season (3577±471, 2591±900 and 2181±360). Following analysis of the variables over the three seasons, the correlation pattern of female body weight with total fecundity (r=0.91, n=458; P<0.001) and relative fecundity (r=?034, n=451; P<0.001) proved similar to that described in other salmonid females. Fertilization rate and survival to the eyed egg stage were also positively correlated (r=0.73, n=453; P<0.001). The systematically high values obtained for these latter variables over the seasons evaluated (consistently above 90%) are clearly greater than those we registered in other species of salmonids bred in Chile under similar conditions and suggest highly efficient biological variables that determine the gamete fertilization of this species. The brown trout is, therefore, an interesting potential aquaculture resource in Chile. 相似文献
73.
Bacteria are known to influence domoic acid (DA) production by Pseudo-nitzschia spp., but the link between DA production and physiology of diatoms requires more investigation. We compared a toxic P. multiseries to a non-toxic P. delicatissima, investigating links between DA production, physiological parameters, and co-occurring bacteria. Bacterial communities in cultures of both species were reduced by antibiotic treatment, and each of the diatoms was inoculated with the bacterial community of the other species. The physiology of P. delicatissima was minimally affected by the absence of bacteria or the presence of alien bacteria, and no DA was detected. P. multiseries grew faster without bacteria, did not produce a significant amount of DA, and exhibited physiological characteristics of healthy cells. When grown with alien bacteria, P. multiseries did not grow and produced more DA; the physiology of these cells was affected, with decreases in chlorophyll content and photosynthetic efficiency, an increase in esterase activity, and almost 50% mortality of the cells. The alien bacterial community had morphological and cellular characteristics very different from the original bacteria, and the number of free-living bacteria per algal cell was much higher, suggesting the involvement of bacteria in DA production. 相似文献
74.
Multidrug-resistant (MDR) Escherichia coli, mainly extraintestinal pathogenic E. coli (ExPEC), has been widely reported in infections worldwide. In agricultural soils, manure is a hotspot for the dissemination of antimicrobial resistance genes (ARGs) and pathogenic bacteria; however, MDR bacteria have also been reported in soils with no history of manure use. In addition, cross-resistance and co-resistance have been described as responsible for the metal-driven selection of bacteria resistant to antimicrobials. Therefore, the aim of this study was to analyze three MDR E. coli isolates obtained from Brazilian grain culture soil samples with no history of manure use by whole-genome sequencing. The MDR E. coli isolates were recovered from soils from corn and coffee fields, and presented resistance to β-lactams, quinolones, aminoglycosides, tetracyclines, sulphonamides, and dihydrofolate reductase inhibitor. Resistome analysis showed ARGs to several antimicrobials (i.e., β-lactams, tetracyclines, aminoglycosides, sulphonamides, trimethoprim, phenicols, fosfomycin, and macrolides) as well as several metal resistance genes and antibacterial biocide resistance genes. In addition, known mutations in quinolone-resistance-determining regions of GyrA (Ser83Leu and Asp87Asn), ParE (Ser458Thr), and ParC (Ser80Ile) were also detected. Virulome analysis showed the presence of virulence genes (lpfA, mcmA, gad, mchF, iroN, cma, and iss) associated with ExPEC. Multidrug-resistant ExPEC isolates were assigned to phylogenetic group B1. The presence of MDR B1-ExPEC in soil samples shows the ability of these isolates to survive in soils. This study reports for the first time some sequence types (i.e., ST345, ST448, and ST1146) of MDR E. coli in Brazilian soils. Therefore, these findings contribute to the monitoring of antimicrobial resistance and surveillance studies based on whole-genome sequencing worldwide. 相似文献
75.
Carvalho Thayslan Brosinsky Arlena Foerster Saskia Teixeira Adunias Medeiros Pedro 《Journal of Soils and Sediments》2022,22(9):2557-2577
Journal of Soils and Sediments - Soil erosion by water yields sediment to surface reservoirs, reducing their storage capacities, changing their geometry, and degrading water quality. Sediment... 相似文献
76.
This investigation examined the effects of live prey availability on growth and survival of Sepia officinalis. Two independent experiments, comprising two feed rations each, were performed, using adequate prey size. In the first experiment, cuttlefish hatchlings were fed live mysids, Paramysis nouvelli [(feed ratio I (fr I)], at 15% body weight per day (bw day?1) (fr I15) and 30% bw day?1 (fr I30). In the second experiment, juvenile cuttlefish were fed live Atlantic ditch shrimp, Paleomonetes varians (fr II), under the same experimental design. In both experiments, the final mean weight, feeding rate and instantaneous growth rate were higher when animals were fed feed ratio fr II15 and fr II30 (30% bw day?1). The results indicate that prey availability influenced weight gain, irrespective of the prey used, during the first 2 months of cuttlefish life cycle. This effect seems to be more noticeable when a certain limit of prey is achieved. For cuttlefish fed fr II, the optimal prey density is thought to be under 2.5 g prey L?1 (i.e. 14 shrimp L?1). Results indicate that cuttlefish can withstand prey densities up to 120 mysids L?1 for cuttlefish up to 3 weeks old and 19 shrimps L?1 for cuttlefish up to 6 weeks old. 相似文献
77.
Karim Sorkheh Behrouz Shiran T. M. Gradziel B. K. Epperson Pedro Martínez-Gómez E. Asadi 《Euphytica》2007,156(3):327-344
Amplified fragment length polymorphism (AFLP) analysis is a rapid and efficient method for producing DNA fingerprints and
molecular characterization. Our objectives were to: estimate genetic similarities (GS), marker indices, and polymorphic information
contents (PICs) for AFLP markers in almond cultivars; assess the genetic diversity of almond cultivars and wild species, using
GS estimated from AFLP fingerprints and molecular characterization; and facilitate the use of markers in inter-specific introgression
and cultivar improvement. The genetic diversity of 45 almond cultivars from Iran, Europe, and America, were studied assaying
19 primer combinations. In addition, several agronomic traits were evaluated, including flowering and maturity times, self-incompatibility,
and kernel and fruit properties. Out of the 813 polymerase chain reaction fragments that were scored, 781 (96.23%) were polymorphic.
GS ranged from 0.5 to 0.96, marker indices ranged from 51.37 to 78.79, and PICs ranged from 0.56 to 0.86. Results allowed
the unique molecular identification of all assayed genotypes. However, the correlation between genetic similarity clustering
as based on AFLP and clustering for agronomic traits was low. Cluster analysis based on AFLP data clearly differentiated the
genotypes and wild species according to their origin and pedigree, whereas, cluster analysis based on agronomic data differentiated
according the pomological characterization. Our results showed the great genetic diversity of the almond cultivars and their
interest for almond breeding. 相似文献
78.
André M. Almeida Anabela B. Silva Susana S. Araújo Luís A. Cardoso Dulce M. Santos José M. Torné Jorge M. Silva Matthew J. Paul Pedro S. Fevereiro 《Euphytica》2007,154(1-2):113-126
We have previously obtained several lines of tobacco transformed with a trehalose-6-phosphate synthase gene of plant origin
(Arabidopsis thaliana), involved in the first step of the biosynthesis of trehalose, a known osmoprotectant. Two showed distinct intensity of expression:
high (B5H) and low (B1F). Such lines were analyzed for trehalose-6-phosphate content and the obtained results demonstrated
to be in accordance with the expression results. In order to study the responses of photosynthesis to water deficit of transgenic
lines in comparison to wild type (WT), three experiments were performed under different conditions: (1) Relative water (2)
Leaf gas exchange (3) Modulated Chlorophyll a Fluorescence. Different responses in RWC of plant lines to water withdrawal were detected, with transgenic line B5H indicating
less water loss after the water withdrawal period. Similar responses to water deficit regarding the leaf gas exchanges were
recorded for the three lines. When subjected to water deficit stress situations, higher F
v/F
m, ΦPSII and qP were detected for the transgenic lines. Under a SWC of 20% where higher values for such parameters were detected with
special relevance for the B5H line, indicating a possible higher ability to withstand severe drought stress and to resist
to prolonged periods without water than the B1F and WT lines. 相似文献
79.
The objectives of this study were to optimize RAPD and AFLP techniques in B. catharticus, and to determine the genetic variability of populations and commercial prairie grass cultivars with the aforementioned molecular
markers. Two populations with contrasting morphological characteristics were evaluated from individual and bulked DNA samples
using RAPD markers. Both analyses showed a similar information about inter population variability. Each accession was sampled
by a single leaf bulk of 10 plants. Accession similarities were established with 276 RAPD and 714 AFLP bands using Jaccard
similarity coefficient. The dendrogram of the accessions using RAPD markers showed that they shared high similarity values
(>94%). A similar result was obtained with AFLP markers (similarity values >98%), revealing a narrow genetic basis in the
analyzed accessions. Consequently, molecular characterization of germplasm should be considered in addition to morphological
criteria, to choose the parental genotypes for breeding programs of this forage crop. The AFLP technique was more efficient
to detect DNA polymorphism in our experiments and unique fingerprints were detected for all the accessions. RAPD is a simple
and non expensive technique, suitable to estimate genetic similarity.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
80.
Raquel Sánchez-Pérez Encarnación Ortega Henri Duval Pedro Martínez-Gómez Federico Dicenta 《Euphytica》2007,155(3):381-391
The inheritance of 16 important agronomic traits and its relationship were studied for four years in a population of 167 almond
[P. dulcis (Mill.) D.A. Webb] seedlings obtained from a cross between the French selection ‘R1000’ (‘Tardy Nonpareil’ × ‘Tuono’) and
the Spanish cultivar ‘Desmayo Largueta’. For some traits (blooming and leafing date) descendants segregated between the value
of both progenitors, meanwhile for others the mean of the offspring was lower (bloom density, productivity and ripening date)
or higher (in-shell/kernel ratio and double kernels). As expected, kernel bitterness and self-incompatibility behaved as monogenic
traits. Some important correlations between traits were detected. The implications of the transmission and the correlation
of these traits in the breeding programmes are discussed. 相似文献