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This literature review focuses on two groups of landowners in the US and Finland: those current family owners who have recently become forest owners, with a relatively short duration of ownership, and private individuals who can be expected to become forest owners in the future are compared. The former group is called “new owners,” and the latter “future owners,” respectively. This study aims to find what can be concluded about future owners from studies of new owners based on the assumption that new owners are interpreted to represent future owners in these studies. The data consists of eight studies conducted after the mid 90s.  相似文献   
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Empirical forest owner classifications typically distinguish groups based on owners’ behaviour or motivations. Typologies are used to inform forest and environmental policies and market-based service provision. However, single typologies may be weak in discerning owner groups that would bring new insights for policymakers or service providers. The present study aims to put together two previously documented owner classification frameworks to form and analyse customer segments for decision-support services. The first grouping is based on owners’ objectives for forest ownership, while the second grouping focuses on owners’ decision-making styles. These two typologies deal with subjects of interest and motivations for communication, respectively. The study uses a subsample of the Finnish Forest Owner 2010 survey data, collected in 2009 (n = 2,106). Via cross-tabulation of the two groupings, the four largest and potentially most interesting combined owner groups are discerned: multiobjective learners (13 %), multiobjective thinkers (9 %), learning recreationists (8 %) and learning investors (7 %), while the other 16 combined groups each account for less than 6 % of owners. The result thus reveals the need for learning-oriented services for three differing principal subjects of interest as well as multiobjective services for deliberate thinkers, i.e. comparative information about forest management alternatives. The message for policymakers and service providers is that the majority of forest owners may be served with educative interactive services. Learning-oriented indifferent owners need special services to recognize their latent goals. Delegators need ready-made services for outsourced decision making and self-reliant owners need information packages of varying contents. Combinations of groups prove feasible for producing policy advice.  相似文献   
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The aim of this study was to investigate the prevalence of antibodies against zoonotic agents in employees of the zoological garden of Vienna, Sch?nbrunn, Austria. Sixty out of 120 employees participated in the study. In 97% of them antibodies to at least one zoonotic agent were identified. Only two participants were free of antibodies to the zoonotic agents tested. The following seroprevalences (in brackets) were obtained: Viral zoonotic (and potentially zoonotic) agents: Influenzavirus A/H1N1 (58%), Influenzavirus A/H3N2 (85%), Lymphocytic choriomeningitis virus (13%), Encephalomyocarditis virus (5%), Orthopox- (Cowpox-) virus and Hantavirus type Puumala (3%). Hantavirus type Hantaan and Borna disease virus (all negative). Bacterial zoonotic agents: Bartonella henselae (65 %), Borrelia burgdorferi (10%), Leptospira interrogans serovar copenhageni and serovar icterohaemorrhagiae as well as Chlamydophila psittoci (2% each). Brucella spp., Coxiella bumetii, and Francisella tularensis (all negative). Parasitic zoonotic agents: Toxoplasma gondii (53%), Toxocara spp. (21%), Capillaria hepatica (2%), Fasciola hepatica, Schistosoma mansoni, E. multilocularis, and E. granulosus (all negative). The remarkably high seroprevalence to the causative agent of cat scratch disease, Bartonella henselae, is probably due to the private contact of the employees to cats. Regarding viral zoonotic agents it has to be mentioned that Influenzavirus vaccination and/or human-to-human transmission of especially A/H3N2 Influenzaviruses probably attributed significantly to the very high seroprevalence to both Influenzavirus types A/H1N1 and A/H3N2. When investigating parasitic zoonotic agents, high prevalence rates were found against Toxoplasma gondii and Toxocara spp., however, it was not possible to establish a causal link between seropositivity and the professional activity in the zoo. Interestingly, in the case of antibodies to T. gondii, the typical correlation with age was not found in this study, while in the case of the Toxocara spp. positive subjects a correlation was identified with both age and duration of employment in the zoo. Regarding the later two zoonotic parasites, employees of the zoological garden showed significantly higher seroprevalences than the average Austrian population. Antibodies to Capillaria hepatica, a hepatic-parasite in rodents which is diagnosed in humans rarely, were identified in one employee and another one showed a questionable positive result. Further investigations did not exhibit clinical infestations with the parasite in these two individuals so far.  相似文献   
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Rye bran was fractionated on a pilot scale into water-extractable, alkali-extractable and unextractable fractions. The fractions were enzymatically digested to partially remove starch and protein. The enzyme treated substrates were fermented in vitro using a human faecal inoculum. The water- and alkali-extractable fractions were fermented faster than the unextractable fraction and rye bran itself. However, the extent of fermentation after 24 h was similar in each case. The production of gases and short-chain fatty acids correlated well with the consumption of neutral sugars. All the rye substrates enhanced the molar proportion of propionic and butyric acids, among the short chain fatty acids.  相似文献   
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In this study, 221 two‐year‐old hatchery‐reared salmon, Salmo salar, smolts were tagged with radio transmitters over a period of three consecutive years and released in the river in groups of 20–21 fish in various dates between late April and early June. Tagged smolts were tracked during their downstream migration in the lower 36‐km stretch of the regulated River Oulujoki, with the focus on the effects of release date, water temperature and river flow on migration behaviour and survival. The results indicate that release timing and river temperature have profound effects on the initiation of migration, swimming speed and survival of released S. salar smolts. Smolts released early in the spring in cold waters ceased migration after brief downstream movement and were vulnerable to predation, whereas the migration speed and survival rates increased markedly for smolts released later in the spring.  相似文献   
7.
Migration behaviour, route selection and mortality of Atlantic salmon, Salmo salar L., smolts were studied at four different hydroelectric facilities in the River Mustionjoki, Finland, in May 2017. Radio-tagged smolts were released upstream of the power stations and tracked by stationary antenna-receiver systems and hand-held receivers. Tracking revealed a general tendency of smolts to move downstream with the main flow, but also variable behaviour and mortality related to diverse conditions characteristic of each power station. Average migration delay at the power stations ranged between 13.8 and 101.1 h (median: 1.7–61.5 h). Estimated mortality ranges were 0%–50% in the forebays, 4%–64% in the power stations and 2–30%/km during river migration after passage of the dam. This study provided essential information on behaviour and mortality in relation to local conditions at each power station required for successful application of fish bypass systems in a salmon restoration project.  相似文献   
8.
The perch population of Lake Vähä Valkjärvi, a two hectare clear-water lake in southern Finland, decreased due to acid precipitation during the 1980s. During the early 1990s a decrease in acidic deposition resulted in slight improvement of water quality of the lake. This was followed by recovery of the reproduction of perch starting in 1991. A mark and recapture experiment in spring 1995 indicated a hundred fold increase in the population size of perch in a four year period. A decrease in the abundance of aquatic invertebrates was recorded during 1989–1996. This decrease well coincided with the recovery of the perch population, suggesting that increased predation by fish was responsible for the decrease. The occurrence of goldeneye young also dropped in L. Vähä Valkjärvi since 1993. This was thought to be due to increased food competition with perch.  相似文献   
9.
The group of female forest owners is growing across Europe and currently estimated to be about 30% of all private owners. This new category of forest owner merits a closer look. By introducing a gender perspective across three different research frameworks, this paper substantiates that gender matters in forest ownership, management, operations, and the understandings of these three aspects. Where gender-disaggregated data is available, and gender is assessed as an empirical variable, we find the differences in numbers between male and female forest owners in most countries. By adding the concept of gender as a relational and structuralizing category, we demonstrate that gender structures affect, for example, actual behavior of female and male forest owners and the self-evaluation of forestry competence. Further, when considering gender as a meaning category we explore how meaning produces behavior and behavior produces meanings, and how both shape institutions and natural and artificial matter. Here forestry competence is the applied example. To further increase the knowledge on new forest owners, we recommend (i) fellow researchers in the field to assume that gender matters and design their empirical studies accordingly and (ii) policy-makers to guarantee access to gender-disaggregated data in official registers and statistics.  相似文献   
10.
We report core stratigraphy and chronology that explains the diachronic history of the surface in a prehispanic wetland agricultural complex of planting platforms and canals at Mandinga, central Veracruz, Mexico. Using recognizable stratigraphic horizons, elevations of prehistoric surfaces were measured for the wetland prior to the construction of platforms and canals, immediately following construction, at the time of abandonment, and of the present-day surface. Significant topographic and hydrological changes are evident. We discuss our results in the light of prehispanic water management and cultivation and postulate water storage within the wetland, a patchy management of water and cultivation, and variable productivity. The paper ends with a discussion of the lessons that can be learned when contemplating contemporary cultivation of wetlands. In addition to the environmental concerns, we emphasize the need to consider the physical, socio-economic, and political contexts in which contemporary wetland agriculture would have to operate.  相似文献   
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