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131.
Zerihun Nigussie Atsushi Tsunekawa Nigussie Haregeweyn Enyew Adgo Makoto Nohmi Mitsuru Tsubo Dagnachew Aklog Derege Tsegaye Meshesha Steffen Abele 《Small-Scale Forestry》2017,16(2):219-233
The development of woodlots as an additional source of livelihood and as a land management option for small-scale farmers is a challenging issue in the cereal-based subsistence farming systems of north-western Ethiopia. There is a need to understand why and which factors determine the decisions of small-scale farmers to grow short-rotation woodlots on their land. Data used in this study were collected from a survey of 200 randomly selected households in the region. A Tobit regression model was used to determine predictor variables for farmers’ decisions to allocate land to planting Acacia decurrens (J.C. Wendl.) Willd. and at what density trees are planted on the respective plots. The most important motivations for planting A. decurrens were income, soil fertility management, and soil and water conservation. Having a male head of household, long distance to markets and plots being on marginal land, among other factors, increased the allocation of land to A. decurrens woodlots. Having a male head of household, access to credit and plots being on marginal land, among other factors, increased tree planting density. Age had a negative effect on both allocation of land to woodlots and tree density, whereas farm size had an inverted U-shaped relationship with both decisions. These results suggest that wider expansion of A. decurrens-based plantation systems could be achieved through improving extension, credit access and road infrastructure to connect small-scale farmers to markets and finance. 相似文献
132.
Climate change spurs havoc on social-ecological system. People and places vulnerable to climate change have been the focus of many discussions. However, in the forestry sector, limited studies have been conducted that link human vulnerability to recent initiatives, such as reducing emissions from deforestation and forest degradation or REDD+, especially in highly vulnerable countries. Using case studies from the Philippines, this paper focuses on the vulnerability of two community-based forest management (CBFM) organizations, with and without REDD+ readiness intervention, to show the impacts of climate variability and extremes. Two balance-weighted approaches, the livelihood vulnerability index and the IPCC-framework, were used in the vulnerability assessments. Results revealed high vulnerability of both CBFM organizations, although Malitbog Upland Developers for Sustainable Association (MUDSA) livelihood vulnerability is largely aggravated by its exposure to disaster, climate variability and extremes, accessibility to health facilities and water supply. The long history of CBFM implementation in both organizations have minimal contribution in enhancing the adaptive capacity of members to cope with and adapt to climate change impacts. REDD+ (readiness), does not insure reduced vulnerability to climate change, unless sustainable livelihood is achieved. As the State controls forest resources, the rights of CBFM-organizations to commercially benefit from these resources are limited, a disincentive to the development of new and viable development programs in CBFM areas, such as REDD+. This also constrains the achievement of climate resiliency. 相似文献
133.
We investigated the soil and soil water chemistry in abandoned terraced paddy fields (reed stand) and a thicket of deciduous
broad-leaved trees (thicket stand) on the same slope in Sado Island, Japan. The soils gathered from these plots were incubated
under different water conditions to examine the dynamics of dissolved ions. The organic carbon pool in the soil in the reed
stand at the lower slope position was greater than the thicket stand at the middle slope position. The high concentration
of base cations and an almost neutral pH of the soil water at the reed stand corresponded with the high exchangeable cation
concentrations and base saturation in the soil. These results reflect the mineral-rich groundwater percolating down the slope,
which may be produced by chemical weathering. An in situ sulfate reduction in the reed stand at deeper soil horizons was identified.
The different water conditions in the incubated soils affected the soil pH(H2O), transformation of Fe, and dominant anions (NO3
−, HCO3
−, and SO4
2−). These biogeochemical processes were more conspicuous in the reed stand at the lower slope position where the concentrations
of organic matter and base cations were high. When the abandoned terraced paddy field is developed for the conservation of
the Japanese crested ibis (Nipponia nippon) habitat in Sado Island, the reductive subsoil at the lower slope position should be kept waterlogged to limit sulfuric acid
generation. 相似文献
134.
Yoshiuchi R Matsubayashi M Kimata I Furuya M Tani H Sasai K 《Veterinary parasitology》2010,174(3-4):313-316
Compared with other countries, surveys of these parasites have been rarely performed in companion animals of Japan in spite of their significance for public health. Here, we investigated pet dogs and cats in Japan for the first time, and genetically analyzed the isolates to evaluate the risk of zoonotic infections. Seventy-seven fecal samples were collected from privately owned dogs and 55 samples from owned cats in Osaka city, Japan. Cryptosporidium oocysts were identified in 3/77 dogs (3.9%) and 7/55 cats (12.7%), and Giardia infection in 2/77 dogs (2.6%) and 1/55 cats (1.8%). Amplification of the target regions for genotyping was successful, Cryptosporidium isolates in dogs and cats were identified as C. canis and C. felis, respectively, and those of Giardia in dogs and cats were G. intestinalis Assemblages D and F. The discharge period of the oocysts varied within 3-16 weeks and that of the cysts was 12 weeks. To date, zoonotic types of both parasites have been identified in other animals in Japan, and further large-scale studies are needed to determine the distribution of zoonotic genotypes in these animals, especially those closely associated with humans. 相似文献
135.
Masaaki Satoh Makoto Saito Kohsuke Tanaka Sumako Iwanaga Salem Nagla Elwy Salem Ali Takahiro Seki Seiji Okada Michinori Kohara Shinji Harada Chieko Kai Kyoko Tsukiyama-Kohara 《Comparative immunology, microbiology and infectious diseases》2010,33(6):e81-e88
In this study, we infected NOD/Scid/Jak3null mice engrafted human peripheral blood leukocytes (hu-PBL-NOJ) with measles virus Edmonston B strain (MV-Edm) expressing hepatitis C virus (HCV) envelope proteins (rMV-E1E2) to evaluate the immunogenicity as a vaccine candidate. Although human leukocytes could be isolated from the spleen of mock-infected mice during the 2-weeks experiment, the proportion of engrafted human leukocytes in mice infected with MV (103–105 pfu) or rMV-E1E2 (104 pfu) was decreased. Viral infection of the splenocytes was confirmed by the development of cytopathic effects (CPEs) in co-cultures of splenocytes and B95a cells and verified using RT-PCR. Finally, human antibodies against MV were more frequently observed than E2-specific antibodies in serum from mice infected with a low dose of virus (MV, 100–101 pfu, and rMV-E1E2, 101–102 pfu). These results showed the possibility of hu-PBL-NOJ mice for the evaluation of the immunogenicity of viral proteins. 相似文献
136.
137.
Iimure T Kimura T Araki S Kihara M Sato M Yamada S Shigyou T Sato K 《Journal of agricultural and food chemistry》2012,60(6):1548-1554
Beer foam stability is an important characteristic. It has been suggested that isoforms of protein Z, that is, protein Z4 and protein Z7, contribute to beer foam stability. We investigated the relationship between beer foam stability and protein Z4 and protein Z7 using their deficient mutants. As a protein Z4-deficient mutant, cv. Pirkka was used. Protein Z7 deficiency was screened in 1564 barley accessions in the world collection of Okayama University, Japan. The barley samples from normal, protein Z4-deficient, protein Z7-deficient, and double-deficient were genotyped in F(2) populations and then pooled based on the DNA marker genotypes of protein Z4 and protein Z7. For a brewing trial, F(5) pooled subpopulations were used. After malting and brewing, the foam stability was determined, and the results showed that the levels of foam stability in the four samples were comparable. Two-dimensional gel electrophoresis was used to investigate the proteome in these beer samples. The results showed that low molecular weight proteins, including lipid transfer protein (LTP2), in the deficient mutants were higher than those in the normal sample. Our results suggest that the contribution of protein Z4 and protein Z7 to beer foam stability was not greater than that of other beer proteins. 相似文献
138.
K. Makoto H. Shibata Y. S. Kim T. Satomura K. Takagi M. Nomura F. Satoh T. Koike 《Biology and Fertility of Soils》2012,48(5):569-577
Ecological function of charcoal has been mainly investigated by adding charcoal to soil, which is not fully adequate to understand in situ the role in fire-prone forest ecosystem. To determine in situ effects of charcoal on ecosystem functions, such as nutrient availability, we conducted an experimental burning in a Japanese white birch forest with dense coverage of dwarf bamboo in the understory with or without removal of charcoal. Ammonium-N in the remaining humus layer increased immediately after the burning, but decreased to the level of unburnt plots within 1?month of the burning. Removal of charcoal had no significant effect on the NH4 +-N dynamics. Although burning did not affect NO3 ?-N dynamics during the sampling period, charcoal removal led to a slight increase in NO3 ?-N. The available P increased immediately after the burning, but then fell at 1?month after burning. Charcoal inhibited the available P depletion and prolonged the high availability of P. Greater availability of P might be due to the adsorption of phosphate in charcoal pores. Exchangeable Ca and Mg increased gradually; charcoal appeared to extend the period of higher concentration of exchangeable Ca and Mg. Charcoal deriving from fire is a key factor in influencing available nutrient in the humus layer of post-fire forests. 相似文献
139.
Mie Araki Aya Numaoka Makoto Kawase Kenji Fukunaga 《Genetic Resources and Crop Evolution》2012,59(7):1303-1308
We developed PCR-based markers for genotyping Waxy genes in common millet (Panicum miliaceum L.) and proposed a new hypothesis on the origin and dispersal of waxy type of Japanese landraces. I2-K staining indicated that almost all the Japanese landraces had waxy endosperm. Based on the PCR and dCAPs analyses of two waxy loci on different genomes we concluded that there were at least two possible lineages in Asian continent that had independent dispersal pathways into Japan. Most Japanese common millet had the similar genotypes with those in Korean Peninsula but a few particularly from northern part of Japan had common genotypes in northeastern China and Primorskaya Province of Russia. 相似文献
140.