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Eucalypt (Eucalyptus spp.) tree farming is a source of income for many smallholders in developing and emerging countries and critical to the resource
supply of many pulp and paper companies. These companies rely on smallholders adopting tree farming, sometimes by offering
a contract. This paper reports a study from four regions of Thailand, where smallholder eucalypt tree farming is important,
which investigated what characteristics of smallholders were associated with greater adoption of tree farming. A total of
461 eucalypt tree farmers and 171 non-tree farmers were randomly selected and surveyed in these regions, using a door-to-door
household survey. A logit analysis corroborated hypotheses about the drivers of adoption. Qualitative analyses were used to
inform interpretation of the quantitative results and shed light on the role of eucalypt tree farming in smallholders’ livelihood.
Results demonstrate that those with suitable land available are more likely to adopt eucalypt tree farming than others. In
addition, perception of land tenure security matters in the adoption of tree growing, but holding a formal land tenure document
does not. Adoption of eucalypt tree farming in Thailand is not part of a land use intensification strategy. Instead, eucalypts
are used as an alternative crop for low productivity land, on which eucalypts are the most profitable crop. Eucalypt tree
farming also gives smallholders an opportunity to diversify their income. In addition, this alternative land use has the advantage
of requiring low labour inputs between planting and harvest. This is particularly advantageous for many tree growers who have
off-farm income or rely on hired labour for farming their land. 相似文献
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Luca Bragazza Paola Iacumin Chiara Siffi Renato Gerdol 《Biology and Fertility of Soils》2010,46(8):877-881
In this study, we describe the seasonal variation in 15N abundance in the litter of two Sphagnum species and four vascular plant species during 3 years of field decomposition in an Italian Alpine bog. Litter bags were periodically retrieved at the end of summer and winter periods, and the δ15N in residual litter was related to mass loss, litter chemistry, and climatic conditions. In Sphagnum litter, higher rates of decomposition during summer months were associated with an increase of δ15N probably due to the incorporation of microbial organic compounds rich in 15N. The litter of Eriophorum vaginatum and Carex rostrata was characterized by a decrease of δ15N, so that the final signature was significantly lower than in initial litter. On the other hand, the residual litter of Potentilla erecta and Calluna vulgaris was characterized by a final δ15N higher than in initial litter. Our data reported a seasonality of 15N abundance in the residual litter of Sphagnum species, but not in that of vascular plant species, thus highlighting the role of differences in litter chemistry. 相似文献
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Lorenza Pacini Felipe Yunta Arwyn Jones Luca Montanarella Pierre Barrè Sergio Saia Songchao Chen Calogero Schillaci 《European Journal of Soil Science》2023,74(4):e13391
Soil Bulk Density (BD) is an extremely important variable because it is an important site characterization parameter, and it is highly relevant for policy development because it is mandatory for calculating soil nutrient stocks. BD can influence soil chemical properties, land-use planning and agronomic management. The 2018 Land Use and Coverage Area Frame Survey (LUCAS) saw the unprecedented collection of BD core analysis in a subset of the locations in Europe and the United Kingdom where soil physical and chemical properties were analysed in the 2009 and the 2015 sampling campaigns. Here, we integrated the LUCAS 2018 BD sampling campaign with the mass fraction of coarse fragments previously determined in LUCAS 2009–2015 in order to provide a dataset of the volume fraction of coarse fragments and the BD of the fine earth and improve soil organic carbon (SOC) stock estimation accuracy for topsoil. BD data sampled at 0–10 and 10–20 cm were averaged to harmonize the BD with the mass fraction of coarse fragments measured in 2009, 2012 and 2015. Samples were from cropland, grassland and woodland soils, which accounted for 41%, 21% and 30%, respectively, of the total number of selected sites (n = 6059); ‘bareland’, and ‘shrubland’ accounted for 3% of the sites each, whereas ‘artificial land’ accounted for <1%. Only six samples were classified as ‘wetland’. The dataset was produced assuming the mass density of the coarse fraction to be constant across all LUCAS soil samples. We also estimated the SOC stocks associated with LUCAS 2018 BD and SOC content measurements and showed that correcting the BD by the coarse mass fraction instead of the coarse volume fraction generates SOC stock underestimation. We found the highest deviations in woodlands and shrublands. We showed that, when SOC stock is computed with coarse mass fraction, the error compared with the computation by volume may vary depending on the SOC and coarse mass fraction. This may imply a SOC stock underestimation for European soils. This dataset fits into the big framework of LUCAS soil properties monitoring and contributes both to soil awareness and soil research and assessments, which are two important objectives of the Soil Strategy and the European Soil Observatory (EUSO). 相似文献
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Enzymatic activity often reduces the nutritional value of wheat flour during food manufacturing, causing compound degradation and/or heat damage. The choice of wheat varieties with low enzymatic activity could therefore help to preserve the nutritional quality of food. The aim of this research was to evaluate polyphenol oxidase, alpha-amylase and beta-amylase activities in whole meal flours of 59 accessions belonging to different wheat species and subspecies, cropped in two years. The extraction pH (7.0), reaction pH (5.5) and reaction temperature (45 °C) were determined by preliminary trials. The ANOVA highlighted significant differences for all enzymes among species/subspecies and, for amylases, between cropping years; however, the year influence was overwhelming only for alpha-amylase. Einkorn showed the highest polyphenol oxidase (362.1 ± 9.46 U/g DM) as well as the lowest alpha-amylase (0.20 ± 0.006 CU/g DM) and beta-amylase (12.0 ± 0.36 B3U/g DM) activities. The embryo/scutellum had the highest polyphenol oxidase and alpha-amylase values, followed by the bran and the endosperm; in contrast, beta-amylase was evenly distributed in the bran and the endosperm, and was absent in the embryo/scutellum. 相似文献
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Narayan Chandra Paul Francesca Latronico Arshnee Moodley S?ren Saxmose Nielsen Peter Damborg Luca Guardabassi 《Veterinary research》2013,44(1):52
The current knowledge of in vitro adherence of Staphylococcus pseudintermedius to canine corneocytes is limited to comparative analyses between strains, staphylococcal species or corneocytes collected from different breeds, body sites and hosts. However, the role played by colonization status of corneocyte donors remains unknown. The aim of this study was to evaluate the adherence properties of commensal S. pseudintermedius strains to corneocytes collected from dogs with different colonization status. For this purpose, corneocytes were collected from five dogs that were classified as persistently colonized (D1 and D2), intermittently colonized (D3 and D4) or non-colonized (D5) on the basis of the results of a previous longitudinal study. Adherence to corneocytes originating from each of the five dogs was assessed by an in vitro adhesion assay using four genetically unrelated strains isolated from the colonized dogs (S1 to S4). Irrespective of their host of origin, all strains adhered significantly better to corneocytes from D1 and D2 than to corneocytes from D3, D4 and D5 (P < 0.0001). The mean count of cells adhering to corneocytes from persistently colonized dogs was on average three times higher than the mean count using corneocytes from the other dogs. A significant difference between strains was only observed for one strain-corneocyte combination (S2-D4), indicating that S. pseudintermedius adherence to corneocytes is driven by host factors and only marginally influenced by strain factors. This finding has important implications for understanding and preventing S. pseudintermedius skin colonization and infection. 相似文献
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Nicolas Lugon-Moulin Florian Martin Marc R. Krauss Patrice B. Ramey Luca Rossi 《Water, air, and soil pollution》2008,192(1-4):315-319
In recent years, arsenic (As) has received increased attention as humans may be exposed to it through occupational and environmental exposure. Tobacco (Nicotiana tabacum L.) like other crops can uptake this element from the soil, which may lead to human exposure. Here, we report on a survey on arsenic in cured or processed tobacco leaves obtained from Africa, Asia, Europe, South and North America. A total of 1,431 leaf samples of flue-cured, burley, and Oriental tobaccos were obtained from various sampling locations during 2002 to 2004. Arsenic concentration in the samples averaged 0.4?±?0.6 μg g?1 as determined by inductively coupled plasma-mass spectrometry. Recorded values from most samples showed that concentrations of arsenic were usually found at the lower end of the distribution. Significant differences were found among tobacco types, sampling locations, and crop years. Arsenic concentrations were rather low in the majority of regions investigated, which is compatible with data from the literature. However, sample size was small and sampling geographically restricted. Our results would need to be validated with a larger dataset. 相似文献