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81.
Mario Torralba Elisa Oteros-Rozas Gerardo Moreno Tobias Plieninger 《Strength and Conditioning Journal》2018,71(5):549-559
The wood pastures or hardwood rangelands of the southwestern Iberian Peninsula are complex social-ecological systems created from the long-term interaction of society and the landscape. Dehesa, oak woodlands managed for grazing, cropping, and other forms of production, is the most common rangeland system and one of the most distinctive landscapes. Traditionally characterized by multifunctional low-intensity management that enhances a wide range of ecosystem services, current management has shifted from the traditional toward more intensified models. This paper assesses the coproduction of ecosystem services on dehesa properties by exploring the relationship between biophysical and sociocultural factors and dehesa management practices. Based on 42 surveys we analyze 16 quantitative indicators using multivariate techniques. The results indicate that there are four main dehesa types as defined by their characteristics and management: large heterogeneous operations with diverse products; small and homogeneous operations focused on a reduced number of products; medium-large properties focused on crop production; and midsized properties with easy public access. Management is the result of the dynamics of interacting biophysical and sociocultural factors that influence manager priorities and investments. Management decisions group around the degree of multifunctionality of the operation, the relative importance of crop production, the degree of grazing pressure in the system, and how restrictive public access policy is. We find that in the study area, interactions between all the previously mentioned elements covary consistently, generating bundles of ecosystem services associated with each of three management models based on the intensity of management. 相似文献
82.
J. J. Jiménez A. G. Moreno T. Decaëns P. Lavelle M. J. Fisher R. J. Thomas 《Biology and Fertility of Soils》1998,28(1):101-110
The structure and seasonal changes of earthworm communities were evaluated in a natural savanna and in a improved grass-legume
pasture in a Colombian oxisol over a period of 18 months. One plot of 90×90 m was isolated in each of the systems and each
month five samples of 1 m2×0.5 m and ten of 20×20×20 cm were randomly selected from a stratified block design. Species richness was similar in the two
evaluated plots (seven species), whereas diversity measured by the index, H (Shannon and Weaver 1949) was clearly different, i.e. H=2.89 in natural savanna and H=1.29 in pasture. This is explained by differences in earthworm community structure. The average annual density in the savanna
was 49.8, ranging from 10.8 to 135.8 individuals (ind) m–2, and biomass was 3.3 g m–2 (hand-sorting method), ranging from 0.9 to 11.5 g m–2. In the man-made pasture, density was 80.1 ind m–2 on average, ranging from 24 to 215.8 ind m–2 and biomass was more than tenfold higher, ranging from 29.2 to 110.4 g m–2. This was especially due to the presence of a large glossoscolecid anecic species, Martiodrilus carimaguensis Jiménez and Moreno, which has been greatly favoured by conversion of savanna to pasture. Endogeic species were dominant in
the natural savanna whereas the anecic species accounted for 88% of total earthworm biomass in the pasture. Total earthworm
density and biomass were significantly different in the two systems studied (t-test). The results indicate a clearly positive response of earthworm communities to improved pastures, a type of land use
that is being increasingly adopted in moist neotropical savannas.
Received: 20 October 1997 相似文献
83.
Energy analysis of irrigation delivery systems: monitoring and evaluation of proposed measures for improving energy efficiency 总被引:2,自引:1,他引:1
M. A. Moreno J. F. Ortega J. I. Córcoles A. Martínez J. M. Tarjuelo 《Irrigation Science》2010,28(5):445-460
In Spain, the Ministry of Industry is implementing actions for analyzing the energy efficiency of Water User Associations
(WUAs) by using energy indicators and proposing measures to improve the use of energy. The main objective of this work was
to develop tools to improve energy efficiency in WUAs. These tools were validated by utilizing them in the energy analysis
of 15 WUAs located in Castilla-La Mancha Region (Spain) during the 2007 irrigation season. These tools were also utilized
for the proposal of measures to improve the use of energy. The proposed measures were monitored and evaluated in 7 of the
15 WUAs during the 2008 irrigation season. The developed tools were integrated into a Decision Support System for performing
energy analysis and for proposing measures of energy efficiency improvement. In most of the study cases, an improvement of
the energy efficiency after the implementation of the proposed measures was detected, with an average energy saving of the
10.2%. 相似文献
84.
85.
Moreno A Chiapponi C Boniotti MB Sozzi E Foni E Barbieri I Zanoni MG Faccini S Lelli D Cordioli P 《Veterinary microbiology》2012,156(3-4):265-276
Three subtypes (H1N1, H1N2, and H3N2) are currently diffused worldwide in pigs. The H1N2 subtype was detected for the first time in Italian pigs in 1998. To investigate the genetic characteristics and the molecular evolution of this subtype in Italy, we conducted a phylogenetic analysis of whole genome sequences of 26 strains isolated from 1998 to 2010. Phylogenetic analysis of HA and NA genes showed differences between the older (1998-2003) and the more recent strains (2003-2010). The older isolates were closely related to the established European H1N2 lineage, whereas the more recent isolates possessed a different NA deriving from recent human H3N2 viruses. Two other reassortant H1N2 strains have been detected: A/sw/It/22530/02 has the HA gene that is closely related to H1N1 viruses; A/sw/It/58769/10 is an uncommon strain with an HA that is closely related to H1N1 and an NA similar to H3N2 SIVs. Amino acid analysis revealed interesting features: a deletion of two amino acids (146-147) in the HA gene of the recent isolates and two strains isolated in 1998; the presence of the uncommon aa change (N66S), in the PB1-F2 protein in strains isolated from 2009 to 2010, which is said to have contributed to the increased virulence. These results demonstrate the importance of pigs as mixing vessels for animal and human influenza and show the presence and establishment of reassortant strains involving human viruses in pigs in Italy. These findings also highlighted different genomic characteristics of the NA gene the recent Italian strains compared to circulating European viruses. 相似文献
86.
Inmaculada Moreno Julio Álvarez Nerea García Santiago de la Fuente Irene Martínez Eloy Marino Alfredo Toraño Joaquin Goyache Felipe Vilas Lucas Domínguez Mercedes Domínguez 《Veterinary parasitology》2014,199(3-4):264-267
An outbreak of human leishmaniosis was confirmed in the southwest of the province of Madrid, Spain, between July 2009 and December 2012. Incidence of Leishmania infection in dogs was unchanged in this period, prompting a search for alternative sylvatic infection reservoirs. We evaluated exposure to Leishmania in serum samples from animals in the area with an indirect immunofluorescence test (IFAT). Using promastigotes from six culture passages and a 1/25 threshold titer, we found anti-Leishmania infantum seroreactivity in 9.3% of cats (4 of 43), 45.7% of rabbits (16/35) and 74.1% of hares (63/85). Use of promastigotes from >10 in vitro passages resulted in a notably IFAT lower titer, suggesting antigenic changes during extended culture. Postmortem inspection of seropositive animals showed no clinical signs of infection. The results clearly suggest that asymptomatic hares were the main reservoir in the outbreak, and corroborate IFAT as a sensitive serological surveillance method to detect such cryptic Leishmania infections. 相似文献
87.
Grasslands in ‘Old World’ and ‘New World’ Mediterranean‐climate zones: past trends,current status and future research priorities 下载免费PDF全文
C. Porqueddu S. Ates M. Louhaichi A. P. Kyriazopoulos G. Moreno A. del Pozo C. Ovalle M. A. Ewing P. G. H. Nichols 《Grass and Forage Science》2016,71(1):1-35
Despite their ecological, economic and social importance, grasslands in areas with Mediterranean climates continue to receive limited scientific, political and media attention. The main objectives of this review are to compare and contrast dryland grasslands in the ‘Old World’ regions of the Mediterranean basin (southern Europe, western Asia and North Africa) with those of ‘New World’ regions with Mediterranean climates (Australia and Chile) and to identify common research priorities. The common characteristics and differences in climate, soils, native vegetation, importance of the livestock sector and the socio‐economic background for the different Mediterranean environments are examined. Past trends and the current status of temporary and permanent Mediterranean grasslands are also described. Some common issues between these regions are as follows: (i) adaptation to climate change; (ii) increasing persistence and drought survival of both annual and perennial species; (iii) the important role of forage legumes; (iv) maintaining grassland plant diversity; and (v) improved ecosystem services, such as carbon sequestration, control of soil erosion and wildfires, and preservation of both wild and domestic biodiversity. The favourable climate in these regions, which allows year‐round grazing and the growth of legumes, should be exploited to improve the sustainability of grassland‐based, extensive farming systems and the quality of their animal products, while at the same time improving ecosystem services. The decreasing support for grassland research and development programmes requires increased international scientific and technical cooperation among the few institutions operating in the different Mediterranean‐climate areas of the World to provide innovative and sustainable solutions to farmers. 相似文献
88.
Microhabitat effects on herbaceous nutrient concentrations at the community and species level in Mediterranean open woodlands: the role of species composition 下载免费PDF全文
The presence of a woody canopy in open oak woodlands affects not only the nutrition but also the species composition of the herbaceous community. Yet, the contribution of both effects (changes in nutrient concentrations and species composition) to total resources that are captured by the herbaceous community is not well understood. We assessed the mineral nutrition (N, P, K and Ca) of three herbaceous species and the herbaceous community as well as the species composition in contrasting microhabitats (beneath trees, beneath a leguminous shrub and in open spaces). Both trees and shrubs increased the nutrient concentrations of the herbaceous species that were studied, except for Taraxacum officinale. Their effects were less consistent when the entire community was considered and depended upon the nutrient being analysed. Species richness and N, P and K concentrations were positively associated, suggesting that more nutrients are captured by the herbaceous community as diversity increases. Our results suggest a close relationship between species composition and nutritional value at the community level that may explain the discrepancies observed between both levels of analysis (species vs. community). Thus, farm-level strategies based on the whole herbaceous community may overlook processes operating at the species level, which can be relevant to achieve sustainable management. 相似文献
89.
M. V. Moreno S. A. Stenglein P. A. Balatti A. E. Perelló 《European journal of plant pathology / European Foundation for Plant Pathology》2008,122(2):239-252
Tan spot, caused by Pyrenophora tritici-repentis, is a common disease of wheat (Triticum aestivum) responsible for economic losses in some wheat growing areas worldwide. In this study the pathogenic and genetic diversity
of 51 P. tritici-repentis isolates collected from different ecological regions of Argentina were analyzed. Virulence tests were conducted on 10 selected
wheat cultivars: Buck Halcón, Chris, Gabo, Glenlea, Klein Dragón, Klein Sendero, Max, ND 495, ProInta Guazú and ProInta Imperial.
Data revealed significant differences between all main factors evaluated and the interactions for 19 of the isolates analyzed.
Based on the reaction type of each isolate/cultivar combination, 48 different pathogenic patterns were detected. The molecular
analysis using Inter-Simple Sequence Repeats (ISSR) revealed the existence of 36 different haplotypes among 37 isolates of
P. tritici-repentis originally selected for this study. These results indicate that P. tritici-repentis on wheat in Argentina is a heterogeneous fungus, implying that screening wheat germoplasm for resistance for tan spot disease
requires a wide range of pathogen isolates. 相似文献
90.
E. Escudero L. Vinué T. Teshager C. Torres M.A. Moreno 《Research in veterinary science》2010,88(1):83-87