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111.
The influence of a change from daily to weekly sampling of bulk precipitation on the obtained deposition values was studied with parallel sampling for 8 months at the station of Virolahti in 2004. Due to dry deposition, the deposition values of the whole period were found to be 5–70% higher from weekly sampling than from daily sampling, the biggest difference being for K+, Ca2+, Mg+ and Na+. The collection efficiencies of the summer sampler and the winter sampler compared to the standard rain gauge were studied from daily sampling in 1991–2003 and weekly sampling in 2004–2008. The performance was best in summer and in winter with rain samples (median value 85–88%), while the median value for daily snow samples was 72%. In winter, the total sum of precipitation collected in the daily sampler and the weekly sampler was 78% and 69%, respectively. The deficit in the weekly sampler in winter was concluded to be due to evaporation, while from the summer sampler no evaporation seemed to occur. Use of the precipitation amount measured by the standard rain gauge when calculating annual precipitation-weighted mean values gave higher mean concentrations than the use of the precipitation measured by the deposition sampler itself, the biggest difference of 8–11% being in the sea-salt ions Cl?, Mg+ and Na+. It was concluded that the concentration and deposition values measured by daily and weekly bulk sampling are incompatible, and should not be combined into the same time series. 相似文献
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Gianluigi Mazzoccoli Angelo De Cata Antonio Greco Marcello Damato Nunzia Marzulli Mariangela Pia Dagostino Stefano Carughi Federico Perfetto Roberto Tarquini 《Journal of circadian rhythms》2010,8(1):6
Background
Immunosenescence is a process that affects all cell compartments of the immune system and the contribution of the immune system to healthy aging and longevity is still an open question. Lymphocyte subpopulations present different patterns of circadian variation and in the elderly alteration of circadian rhythmicity has been evidenced. The aim of our study was to analyze the dynamics of variation of specific cytotoxic lymphocyte subsets in old aged subjects. 相似文献115.
Teemu Harrinkari Pia Katila Heimo Karppinen 《Scandinavian Journal of Forest Research》2017,32(1):6-18
Major revisions of the Finnish Forest Act were carried out in 1994–1996 and 2010–2013. The need for revision emerged from societal changes and changes in the forest sector’s operational environment that related to the globalisation of markets and influences of international policies. This study analysed the influences of global and European Union forest and environmental policies on the revision of the Forest Act by combining advocacy coalition framework with the four pathways of influence framework introduced by Bernstein and Cashore. The results show that the three identified advocacy coalitions, namely Forestry administration, Private forestry and Environmental coalition remained rather stable over the two revision processes from 1990s to 2010s. The importance of the different pathways of international influence differed between the coalitions. Private forestry and Forestry administration coalitions, which represented forestry paradigm, stressed market-related arguments, whereas Environmental coalition representing environmental paradigm mainly referred to international legally binding rules and non-legally binding initiatives. The argumentation of the actors indicated that international rules and international norms and discourse were regarded to be as equally important. 相似文献
116.
Pia E. Lentini Tara G. Martin Philip Gibbons Joern Fischer Saul A. Cunningham 《Biological conservation》2012,149(1):84-92
Pollination has received attention recently due to reported sharp declines of Apis mellifera in several locations, and it has been proposed that diverse native bee communities may be key for continued pollination of economically important crops. However, there is some inconsistency in the literature as to how these communities should best be managed. To address this issue, we collected bees from an intensively managed agricultural region in eastern Australia using blue vane traps. Both linear remnants of vegetation, which form part of a larger corridor network, and adjacent fields of native and exotic pastures, wheat, canola, and lucerne were sampled. A total of 3249 individual bees, representing four families and 36 species were collected. Highly modified environments of nectar-bearing crop supported the most species-rich bee assemblages, and the highest abundance of individual bee species. Distance from the remnants did not limit the body size of species occupying fields (up to 400 m). However, richness of bee assemblages also responded positively to the presence of conservation land in nearby areas, or the number of remnant native trees surrounding traps. Linear remnants of native vegetation contributed to assemblage heterogeneity by adding unique species to the regional pool. Our findings indicate that agricultural industries that currently rely on pollination by A. mellifera should ensure that intensive land use is complemented by untilled areas in the form of conservation land, or farm dams and scattered trees in fields, to support wild pollinators that may act as insurance against further future losses of managed hives. 相似文献
117.
Socio-cultural processes behind the differential distribution of organic farming in Denmark: a case study 总被引:1,自引:0,他引:1
Marie-Louise Risgaard Pia Frederiksen Pernille Kaltoft 《Agriculture and Human Values》2007,24(4):445-459
Conversion to organic farming, along with its associated driving forces and barriers, has been explored intensively over the
past decade, while studies on the distribution and impacts of local socio-cultural processes in relation to conversion to
and diffusion of organic farming have been scarce. The concentration of organic farms in Denmark differs according to county
and, moreover, there appears to be large within-county variation in the density of organic farms. The present study explores
local aspects of conversion to organic farming and the factors that may help explain variation in density and concentration
of organic farms within smaller areas. The study is based on nine qualitative interviews with organic farmers from two neighboring
areas, referred to as “mainland” and “island,” respectively. Three farms were situated in the high-density area (mainland)
and the remaining six in the low-density area (island). Furthermore, five advisors with connections to the area provided information
with regard to their local experience and perceptions. Three main, and to some extent interacting, issues are discussed. The
first is the price of land related to local scarcity of land, in the context of structural development and the effects of
agricultural policies. The second is distance – both physical and social. Cooperation and exchange of experience among organic
farmers was frequent on the mainland side, while isolation and lack of interaction was more common for the island farmers.
Third, the role of the agricultural advisory service and the existence of champion farmers are important: pioneer farmers
on the mainland have been supported by committed agricultural advisors, while lack of organic champion farmers and low priority
granted to organic farming among agricultural advisors were found on the island.
Marie-Louise Risgaard
has an MSc within the field of organic agriculture. Her research interests are organic farming and rural development with
the present occupation as innovative partner at a small-scale organic enterprise. In this capacity she is responsible for
creating links between the organic enterprise, the gastronomic sector and organic markets, locally as well as nationally.
Pia Frederiksen, PhD, is a geographer and senior scientist with research skills in rural development, sustainability, landscape analysis, and
agri-environmental indicators.
Pernille Kaltoft, PhD, is an environmental sociologist and senior scientist whose work focuses on organic farming and farmers’ perceptions.
Dr. Kaltoft’s general research interests include values, perceptions, and views of nature related to agricultural and environmental
issues. 相似文献
118.
Tuomisto JT Tuomisto J Tainio M Niittynen M Verkasalo P Vartiainen T Kiviranta H Pekkanen J 《Science (New York, N.Y.)》2004,305(5683):476-7; author reply 476-7