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1.

Context

Human–nature interactions are reflected in the values people assign to landscapes. These values shape our understanding and actions as landscape co-creators, and need to be taken into account to achieve an integrated management of the landscape that involves civil society.

Objectives

The aim of this research was to increase the current knowledge on the most and least common landscape values perceived by local stakeholders, the patterns in the spatial distribution of values, and their connection to different socio-economic backgrounds and landscape characteristics across Europe.

Methods

The research consisted of a cross-site comparison study on how landscape values are perceived in six areas of Europe using Public Participation GIS surveys. Answers were analysed combining contingency tables, spatial autocorrelation and bivariate correlation methods, kernel densities, land cover ratios, and viewshed analyses. Results were discussed in the light of findings derived from other European participatory mapping studies.

Results

We identified shared patterns in the perception of landscape values across Europe. Recreation, aesthetics, and social fulfilment were the most common values. Landscape values showed common spatial patterns mainly related to accessibility and the presence of water, settlements, and cultural heritage. However, respondents in each study site had their own preferences connected to the intrinsic characteristics of the local landscape and culture.

Conclusions

The results encourage land planners and researchers to approach landscape values in relation to socio-cultural and bio-physical land characteristics comprehensibly, acknowledging the complexity in the relationship between people’s perception and the landscape, to foster more effective and inclusive landscape management strategies.
  相似文献   
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In this paper, we investigate how the innovation expectations of public financiers are related to realized patents. The analysis is based on a novel data set of collaborative R&D projects subsidized by the Finnish Agency of Technology and Innovation (Tekes) and the European Regional Development Fund (ERDF) during the period 2000–2004. Innovation expectations are measured using reports submitted by Tekes experts during ex ante assessments of projects. Our probit model results reveal that Tekes' patent expectations are positively related to realized patents for projects led by private firms (but not by public organizations). For large organizations, Tekes' innovation expectations are better at predicting patenting.  相似文献   
3.
Correlations between leaf abscisic acid concentration ([ABA]), stomatal conductance (gs), rate of stomatal opening in response to an increase in leaf water potential (si), shoot hydraulic conductance (L) and photosynthetic characteristics were examined in saplings of six temperate deciduous tree species: Acer platanoides L., Padus avium Mill., Populus tremula L., Quercus robur L., Salix caprea L. and Tilia cordata Mill. Species-specific values of foliar [ABA] were negatively related to the mean values of gs, si, L and light- and CO2- saturated net photosynthesis (P(max)), thus providing strong correlative evidence of a scaling of foliar gas exchange and hydraulic characteristics with leaf endogenous [ABA]. In addition, we suggest that mean gs, si, L and Pmax for mature leaves may partly be determined by the species-specific [ABA] during leaf growth. The most drought-intolerant species had the lowest [ABA] and the highest gs, suggesting that interspecific differences in [ABA] may be linked to differences in species-specific water-use efficiency. Application of high concentrations of exogenous ABA led to large decreases in gs, si and P(max), further underscoring the direct role of ABA in regulating stomatal opening and photosynthetic rate. Exogenous ABA also decreased L, but the decreases were considerably smaller than the decreases in gs, si and Pmax. Thus, exogenous ABA predominantly affected the stomata directly, but modification of L by ABA may also be an important mechanism of ABA action. We conclude that interspecific variability in endogenous [ABA] during foliage growth and in mature leaves provides an important factor explaining observed differences in L, gs, si and Pmax among temperate deciduous tree species.  相似文献   
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The adequate growth of plants can be achieved only by a balanced ratio of biologically active nutrients in soil along with its readily availability. Linseed seems to be an advantageous secondary oilseed crop widely used in industrial purposes, which can serve additional purpose of phytoextraction of heavily infested soils with heavy metals. In this study, we have made an effort to find out the optimum dose of heavy metals necessary as micronutrients like copper (Cu), iron (Fe) and zinc (Zn) for the enhancement of linseed yield along with the distribution of heavy metals in different plant parts. Quantitative enhancement in different traits of linseed plant due to Cu, Fe and Zn fertilization especially for capsules per plant after maturity suggested positive association between heavy metal supply and morphological traits, which indirectly enhanced seed yield. There was a positive correlation between Zn supply and seed yield. In the treatments with Cu and Fe fertilization, seed yield was positively correlated to plant height, capsules per plant and seeds per five capsules. According to this study, it is concluded that linseed has the ability to accumulate majorly Fe followed by Cu and Zn.  相似文献   
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Two surveys (2005/2006 and 2009) were conducted in the state of São Paulo, Brazil, to investigate the incidence of ‘Candidatus Liberibacter asiaticus’ and ‘Ca. L. americanus’, two liberibacters associated with citrus huanglongbing (HLB) disease and both transmitted by Diaphorina citri, in orange jasmine (Murraya exotica), a widespread ornamental tree in cities and villages. The graft‐transmissibility of the two species, and their DNA relatedness to citrus‐associated liberibacters, were also investigated. Quantitative PCR was applied to PCR‐positive orange jasmine and HLB‐positive citrus growing in backyards and orchards to assess their inoculum source potentials. Liberibacters were detected in 91 of 786 sampled orange jasmine plants in 10 of 76 sampled locations. PCR‐positive trees exhibited yellow shoots and/or dieback symptoms indistinguishable from those on PCR‐negative trees. ‘Candidatus Liberibacter americanus’ was more common in 2005/2006 (96·6%) and ‘Ca. L. asiaticus’ in 2009 (84·8%). rplJ nucleotide sequences were identical within all populations of either species. Graft transmission succeeded only in homologous host combinations, including ‘Ca. L. americanus’ (2/10) from/to orange jasmine and ‘Ca. L. americanus’ (5/18) and ‘Ca. L. asiaticus’ (5/9) from/to citrus. Symptoms were mild and developed less rapidly in orange jasmine than in citrus, probably as a result of lower liberibacter multiplication rates. Respective titres of ‘Ca. L. americanus’ and ‘Ca. L. asiaticus’ in orange jasmine averaged 4·3 and 3·0 log cells g?1 tissue, compared with 5·5 and 7·3 in citrus. The results indicate that orange jasmine does not favour liberibacter multiplication as much as citrus. However, its importance in HLB epidemics should not be underestimated as it is a preferred host of D. citri and is not under any strict tree‐eradication programme or measures for insect control.  相似文献   
9.
The possible ameliorative effects of selenium (Se) addition to soil on the detrimental effects of enhanced UV-B radiation were tested on strawberry and barley during 4 months of field experiment in Kuopio, Central Finland. Control plants were exposed to ambient levels of UV radiation, using arrays of unenergized lamps. A control for UV-A radiation was also included in the experiment. Added Se, applied as H2SeO4, at the level of 0.1 mg kg−1 soil (low dosage) and 1 mg kg−1 soil (high dosage) increased Se concentrations in plants more than 10 and 100 times, respectively. After 4 months of exposure, strawberry and barley plants were harvested for biomass analysis. Chlorophyll fluorescence was measured using the Hansatech FMS2 fluorescence monitoring system. Leaf anatomy and ultrastructure were observed by light and transmission electron microscope. Several effects of UV and Se as well as their interaction were found, mostly for strawberry, but not for barley, indicating species-specific responses. Our results provided evidence that the high Se concentration in soil had no ameliorative effect but increased the sensitivity of strawberry to enhanced UV-B radiation in the field. Under ambient radiation, Se did not alter leaf growth of strawberry, whereas under UV-B radiation, the high Se addition significantly decreased leaf growth. Strawberry runner biomass was affected by the interaction of Se and UV. Under ambient radiation Se did not change dry weight of runners, but in combination with UV-A or UV-B radiation the high Se dosage decreased dry weight of runners by about 30%. Although the high Se concentration positively influenced on quantum efficiency of photosystem II (PSII) in strawberry leaves, it reduced runner biomass, leaf number and ratio of starch to chloroplast area. This suggests that the harmful effects of the high Se dosage on photosynthetic processes occurred as a result of changes in activity or/and biosynthesis of enzymes, rather than alteration of PSII. At the low concentration, Se effects were slight and variable.Although barley leaves accumulated higher Se concentrations than strawberry, there were no apparent changes in their growth, biomass or chlorophyll fluorescence due to Se effect either alone or in combination with UV-B. However, at the ultrastructural level, an enlargement in the peroxisome area was found due to combination of UV radiation with Se, suggesting the activation of antioxidative enzymes, possibly catalase. Decrease in mitochondrial density in barley cells in response to Se might be attributed to alteration of mitochondrial division. Increase in the proportion of cells with cytoplasmic lipid bodies due to combined effect of UV-B and Se indicated the alteration of lipid metabolism and the acceleration of cell senescence in barley. Main UV-B effects were found, mostly at the tissue and ultrastructural level in strawberry, but not in barley, indicating species-specific susceptibility to enhanced UV-B radiation. UV-B-treated strawberry plants developed marginally thinner leaves with reduced ratio of starch to chloroplast area in their cells, suggesting negative influence of UV-B on photosynthetic processes.  相似文献   
10.
Hydroponically grown cucumber (Cucumis sativus) seedlings were inoculated with zoospores of 1 mycoparasitic (Pythium oligandrum) and 2 pathogenic (Pythium aphanidermatum and Pythium group F) Pythium spp. During the first 2 days after inoculation, all the Pythium spp. caused reduction in the root length. However, roots treated with Pythium oligandrum quickly reached the length of the control and on the 8th day, and for the rest of the experimental period, stimulation of root elongation was noted. Pythium oligandrum was not pathogenic on cucumber and no differences in the fresh weights of control and Pythium oligandrum inoculated plants were observed in the course of the experiment. Pythium group F and Pythium aphanidermatum were pathogenic on cucumber seedlings, but their pathogenicities differed. Thus, while Pythium group F had a constant, negative influence on root length and plant growth, measured as fresh weight, Pythium aphanidermatum caused generalized necroses of the root system, inhibiting consistently root elongation and plant growth and finally causing plant death. Moreover, the zoospores of 2 mycoparasitic species, Pythium oligandrum and Pythium periplocum, were not attracted to roots of cucumber and accumulated on the roots in very low numbers compared to those of the pathogenic species, Pythium aphanidermatum, which were strongly attracted and accumulated in large numbers. Finally, it was also found that Pythium oligandrum colonized the roots very poorly, while Pythium group F and Pythium aphanidermatum were significantly better root colonizers. The significance of these findings is discussed in relation to the ecology of Pythium species and biocontrol.  相似文献   
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