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1.
The lichen genus Erioderma is shown to be particularly species-rich in Ecuador, especially in the upper cloud forest (3000–3400m). Altogether seventeen species are recorded of which the following are new: E. barbellatum, E. cyathophorum, E. divisum, E. gloriosum, E. papyraceum, E. pycnidiferum, E. sinuatum , most of which also occur in the neighbouring countries. Two further taxa from these are described as new: E. latilobatum from Bolivia and E. peruvianum from Peru and Bolivia. 相似文献
2.
Vijver MG Kruijne R Van 'T Zelfde M Van Der Linden AM Tamis WL De Snoo GR 《Communications in agricultural and applied biological sciences》2011,76(4):879-889
In order to have a thorough evaluation of the progress and effectiveness of Dutch crop protection policy, both model predictions and measured pesticide concentrations in surface waters are considered. To this purpose, monitoring data obtained by various water boards and other monitoring institutes were processed. Data were aggregated over a two year time period and over space (at 1x1 km-grid). A geographic view is given in the Dutch Pesticides Atlas (www.pesticidesatlas.nl). The model used for the predictions was the Dutch National Environmental Indicator NMI version 2 (www.nmi.alterra.nl) that has input data regarding spray drift data, crop interception, soil and climate and many more. Information on aggregation steps over time and space, grid sizes, information on crop areas was geared to one another for both instruments. Results on measured pesticide concentrations in surface waters and model predictions were compared to each other at the national scale. For this study, 10 different cases were selected covering a large range of pesticides' characteristics and pesticides' use. In 60% of the cases, the results were largely in agreement with each other when expressed as absolute numbers of measurements exceeding the environmental quality standard. This is very accurate and useful for policy purposes. Based on concentrations and on the order of magnitude, no significant agreement between measurements and model predictions was found. Differences were explained by various factors, and an overview of predominant systematic differences between the measurements and the model predictions was presented. Using both measurements and model predictions in supporting environmental policy evaluations is warranted, because of higher Weight-of-Evidence. Combining both can assist in optimizing the knowledge on pesticides behaviour, fate and ecological problems and therefore this is the preferred evaluation method. 相似文献
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H.J. De Lange 《Aquatic Ecology》2000,34(3):215-226
The vertical attenuation coefficients (K
d) of downward ultraviolet (UV) and visible irradiance (PAR) were measured in 19 different inland waters in the Netherlands using a scanning spectroradiometer. Water chemistry variables such as dissolved organic carbon (DOC), absorbance of dissolved matter (a
d), chlorophyll-a, and particulate matter were measured to determine the relative contribution of dissolved and particulate components in explaining the variation in K
d. In addition to the field measurements, laboratory measurements were performed to test the relationships between water properties and light attenuation. The attenuation properties of Dutch inland waters vary. In most systems the penetration of UV-B radiation (280–320 nm) is limited to the upper decimetres. Lake Maarsseveen was the clearest waterbody in this study, with K
dUVB of 9.1 (m–1). The DOC concentration had limited power in predicting UV attenuation in this study (r
2=0.33), because of the large differences in carbon-specific absorption. A
d300 was a much better predictor of UV attenuation (r
2=0.75). The relationships obtained in the laboratory experiments can be used to give a good prediction of in situ
K
d values, based on 3 variables (chlorophyll-a, ash weight, and absorption of dissolved matter). 相似文献
7.
Anna Chrtková-Žertová 《Folia Geobotanica》1968,3(1):99-110
The paper deals with some problems of distribution and variability of the speciesL. angustissimus L.,L. halophilus Boiss. etSprun.,L. laricus Rech. fil.,Aellen etEsfandiari, L.,schimperi Steud.,L. compactus Chrtková-?ertová,L. garcinii DC. 相似文献
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Na Yang Zefen Yu Dongchen Jia Zhidan Xie Keqin Zhang Zhenyuan Xia Liping Lei Min Qiao 《Applied microbiology and biotechnology》2014,98(7):2897-2905
Proteins with internal repeats (Pir) in the Baker’s yeast are located on the cell wall and include four highly homologous members. Recently, Pir proteins have become increasingly used as anchor proteins in yeast cell surface display systems. These display systems are classified into three types: N-terminal fusion, C-terminal fusion, and inserted fusion. In addition to the GPI (glycosylphosphatidyl inositol) and the FL/FS anchor proteins, these three Pir-based systems significantly increase the choices for target proteins to be displayed. Furthermore, Pir proteins can also be used as a fusion partner for target proteins to be effectively secreted into culture medium. Here, we summarize the development and application of Pir proteins as anchor proteins. 相似文献
10.
An investigation of polymorphism of 11 autosomal and one sex-linked allozyme loci was made on 18 samples of Anopheles claviger Meigen (Diptera: Culicidae) from localities across France and neighbouring sites in Germany and Switzerland, plus one sample of Anopheles petragnani Del Vecchio from the French Pyrénées. Genetic differentiation between these two sibling species was confirmed (Nei genetic distance 0.33-0.44) and two genetically distinct groups of populations were identified within An. claviger. These two forms of An. claviger showed contiguous geographical distributions, Group I found across western and Central France, Group II in eastern France and nearby parts of Germany and Switzerland. The two groups were in contact in a region near the Rhone Valley where two intermediate samples were found. The taxonomic significance of this finding is discussed in the context of the recent climatic history of Europe and in relation to the vector potential of each member of the An. claviger complex. 相似文献
11.
It is widely believed that the expanding burden of non-communicable diseases (NCDs) is in no small part the result of major macro-level determinants. We use a large amount of new data, to explore in particular the role played by urbanization – the process of the population shifting from rural to urban areas within countries – in affecting four important drivers of NCDs world-wide: diabetes prevalence, as well as average body mass index (BMI), total cholesterol level and systolic blood pressure. Urbanization is seen by many as a double-edged sword: while its beneficial economic effects are widely acknowledged, it is commonly alleged to produce adverse side effects for NCD-related health outcomes. In this paper we submit this hypothesis to extensive empirical scrutiny, covering a global set of countries from 1980–2008, and applying a range of estimation procedures. Our results indicate that urbanization appears to have contributed to an increase in average BMI and cholesterol levels: the implied difference in average total cholesterol between the most and the least urbanized countries is 0.40 mmol/L, while people living in the least urbanized countries are also expected to have an up to 2.3 kg/m2 lower BMI than in the most urbanized ones. Moreover, the least urbanized countries are expected to have an up to 3.2 p.p. lower prevalence of diabetes among women. This association is also much stronger in the low and middle-income countries, and is likely to be mediated by energy intake-related variables, such as calorie and fat supply per capita. 相似文献
12.
The southeast of the Iberian Peninsula is a recognized area of high aquatic biodiversity, water beetles being one of the most
well-known groups contributing to such biodiversity. The standing waters of this area show a high habitat diversity, occurring
fresh, saline, temporary, permanent, karstic, endorheic, and artificial small water bodies. Despite this, there has been no
attempt to analyze their contribution to local biodiversity. In this work, we identify the species inhabiting standing waters,
analyze their contribution to the checklist from the study area, and recognize the species exclusive to this kind of habitat.
We also highlight the most threatened species, identify the habitats which constitute biodiversity hotspots for this group,
explore patterns of water beetle assemblage composition, and identify indicator species associated with each habitat type.
We collected 125 species, 55 of them being typical to lentic habitats, in the set of 26 sampled standing water bodies, which
means the 57% of the 218 species recorded in the most recent checklist for the study area. A total of 10 species are Iberian
endemics and four can be considered threatened, Ochthebius irenae falling in both categories. Natural ponds showed the highest species richness (91 species), while saline water bodies (endorheic
lagoons and continental salt-pans) contributed the most threatened species: Nebrioporus baeticus, Ochthebius delgadoi, Ochthebius tudmirensis and Ochthebius irenae. The most representative species for continental salt-pans was Ochthebius notabilis, for endorheic lagoons Ochthebius marinus and Hygrotus pallidulus, while Hydroglyphus geminus played this part in rice fields. Our results suggest that rice fields, endorheic lagoons, and continental salt-pans have
specific water beetles assemblages, which could be used in bioassessment and conservation studies. In general, standing waters
are seriously threatened in this area, particularly as a result of intensive agricultural activities. Thus, taking into account
these ecosystems hold a high number of species, their continued degradation is likely to result in a significant loss of biodiversity,
including key populations of a number of threatened and endemic species. 相似文献
13.
Latest FAO figures indicate that an estimated 925 million people are undernourished in 2010, representing almost 16% of the population in developing countries. Looking to the future, there are also major challenges ahead from the rapidly changing socio-economic environment (increasing world population and urbanisation, and dietary changes) and climate change. Promoting agriculture in developing countries is the key to achieving food security, and it is essential to act in four ways: to increase investment in agriculture, broaden access to food, improve governance of global trade, and increase productivity while conserving natural resources. To enable the fourth action, the suite of technological options for farmers should be as broad as possible, including agricultural biotechnologies. Agricultural biotechnologies represent a broad range of technologies used in food and agriculture for the genetic improvement of plant varieties and animal populations, characterisation and conservation of genetic resources, diagnosis of plant or animal diseases and other purposes. Discussions about agricultural biotechnology have been dominated by the continuing controversy surrounding genetic modification and its resulting products, genetically modified organisms (GMOs). The polarised debate has led to non-GMO biotechnologies being overshadowed, often hindering their development and application. Extensive documentation from the FAO international technical conference on Agricultural Biotechnologies in Developing Countries (ABDC-10), that took place in Guadalajara, Mexico, on 1-4 March 2010, gave a very good overview of the many ways that different agricultural biotechnologies are being used to increase productivity and conserve natural resources in the crop, livestock, fishery, forestry and agro-industry sectors in developing countries. The conference brought together about 300 policy-makers, scientists and representatives of intergovernmental and international non-governmental organisations, including delegations from 42 FAO Member States. At the end of ABDC-10, the Member States reached a number of key conclusions, agreeing, inter alia, that FAO and other relevant international organisations and donors should significantly increase their efforts to support the strengthening of national capacities in the development and appropriate use of pro-poor agricultural biotechnologies. 相似文献
14.
A C Smaal A Wagenvoort J Hemelraad I Akkerman 《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1991,100(1-2):197-200
1. Mussels were exposed in the Dutch coastal zone and the Western Scheldt estuary. After six weeks of exposure, trace metals, PCBs and PAHs were measured in the soft tissue. 2. Tissue concentrations of contaminants are high in the Western Scheldt and intermediate near the Rhine outflow, except for the lower PCB congeners. 3. Results show that the survival in air is significantly lower at higher tissue concentrations, in particular of the lower PCB congeners. 4. The clearance rate is reduced at the highest tissue concentrations. 相似文献
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16.
Agricultural biotechnologies in developing countries and their possible contribution to food security 总被引:1,自引:0,他引:1
Latest FAO figures indicate that an estimated 925 million people are undernourished in 2010, representing almost 16% of the population in developing countries. Looking to the future, there are also major challenges ahead from the rapidly changing socio-economic environment (increasing world population and urbanisation, and dietary changes) and climate change.Promoting agriculture in developing countries is the key to achieving food security, and it is essential to act in four ways: to increase investment in agriculture, broaden access to food, improve governance of global trade, and increase productivity while conserving natural resources. To enable the fourth action, the suite of technological options for farmers should be as broad as possible, including agricultural biotechnologies. Agricultural biotechnologies represent a broad range of technologies used in food and agriculture for the genetic improvement of plant varieties and animal populations, characterisation and conservation of genetic resources, diagnosis of plant or animal diseases and other purposes. Discussions about agricultural biotechnology have been dominated by the continuing controversy surrounding genetic modification and its resulting products, genetically modified organisms (GMOs). The polarised debate has led to non-GMO biotechnologies being overshadowed, often hindering their development and application.Extensive documentation from the FAO international technical conference on Agricultural Biotechnologies in Developing Countries (ABDC-10), that took place in Guadalajara, Mexico, on 1–4 March 2010, gave a very good overview of the many ways that different agricultural biotechnologies are being used to increase productivity and conserve natural resources in the crop, livestock, fishery, forestry and agro-industry sectors in developing countries. The conference brought together about 300 policy-makers, scientists and representatives of intergovernmental and international non-governmental organisations, including delegations from 42 FAO Member States. At the end of ABDC-10, the Member States reached a number of key conclusions, agreeing, inter alia, that FAO and other relevant international organisations and donors should significantly increase their efforts to support the strengthening of national capacities in the development and appropriate use of pro-poor agricultural biotechnologies. 相似文献
17.
Limnology - Laguna de Bay is the largest multipurpose lake in the Philippines. Of the primary uses, fish cultivation and potable water production depend mainly on its water quality. Over the years,... 相似文献
18.
Hana Skálová 《Folia Geobotanica》2005,40(1):77-90
Morphological parameters ofFestuca rubra clones and their response to differences in the red/far red ratio (R : FR) were investigated in a growth chamber experiment. The twenty-four clones tested came from 15 micro-sites in three neighbouring meadow communities in the Krkono?e Mts. (Czech Republic). The community types were characterized by different canopy height and structure, and by different radiation conditions (relative R : FR) within the canopies. Low R : FR treatment resulted in reduced tillering and stimulated shoot elongation in most of the clones. In some clones, low R : FR ratios stimulated extravaginal tillering and rhizome system formation. The origin of the clones (i.e., community type) explained a part of variation in morphological parameters, but did not explain variation in the response to R : FR levels. Evidence for a consistent relationship between clone performance and radiation environment in the micro-sites from where the clones originated was not found. It seems that there is only limited selection ofF. rubra clones (ecotypes) specialized for particular community types and no selection of clones specialized for particular micro-sites within communities. 相似文献
19.
P. J. Wangersky 《Helgoland Marine Research》1977,30(1-4):546-564
Except for the special cases of upwelled water and the spring blooms in temperate and boreal waters, the productivity of the oceans is largely governed by the rate of nutrient regeneration in surface waters. This rate of regeneration is a function of the number of actively metabolizing bacteria present, which in turn appears to be a function of the particle content of the water. Thus, particle content may be the basic control on the productivity of the open oceans. The possibility of increasing productivity by artificially increasing the particle content of the water should be considered for regions characterized by low particle count, such as the Sargasso Sea. Since silicate can only be resupplied by re-solution of diatom tests, a process taking place at depth, plankton blooms following regeneration kinetics will typically be dinoflagellate rather than diatom blooms. 相似文献
20.
Anna Chrtková-Žertová 《Folia Geobotanica》1977,12(2):201-207
In Iran, Iraq, Turkey and adjacent southern parts of the U.S.S.R., four species of the genusVicia, group ofV. ciceroidea, occur, namelyV. multijuga (Boiss.)Rech. f.,V. ciceroidea Boiss.,V. rafigae Tamam?jan and the new speciesV. sojakii described here. This group of species is distinguished by its tendency to reduction of leaflets, broadening of leaf rhachis and dense branching of stems. With respect to these particular properties it is now convenient to esparate these species as a seriesCiceroideae in the sectionCracca. 相似文献