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101.
Takafumi Miyasaka Quang Bao Le Toshiya Okuro Xueyong Zhao Kazuhiko Takeuchi 《Landscape Ecology》2017,32(4):707-727
Context
Recent conceptual developments in ecosystem services research have revealed the need to elucidate the complex and unintended relationships between humans and the environment if we are to better understand and manage ecosystem services in practice.Objectives
This study aimed to develop a model that spatially represents a complex human–environment (H–E) system consisting of heterogeneous social–ecological components and feedback mechanisms at multiple scales, in order to assess multi-dimensional (spatial, temporal, and social) trade-offs in ecosystem services.Methods
We constructed an agent-based model and empirically calibrated it for a semi-arid region in Northeast China, and examined ecosystem service trade-offs derived from the Sloping Land Conversion Program (SLCP), which is based on payment for ecosystem services. This paper describes our model, named Inner Mongolia Land Use Dynamic Simulator (IM-LUDAS), using the overview, design concepts, and details + decision (ODD + D) protocol and demonstrates the capabilities of IM-LUDAS through simulations.Results
IM-LUDAS represented typical characteristics of complex H–E systems, such as secondary and cross-scale feedback loops, time lags, and threshold change, revealing the following results: tree plantations expanded by the SLCP facilitated vegetation and soil restoration and household change toward off-farm livelihoods, as expected by the government; conversely, the program caused further land degradation outside the implementation plots; moreover, the livelihood changes were not large enough to compensate for income deterioration by policy-induced reduction in cropland.Conclusions
IM-LUDAS proved itself to be an advanced empirical model that can recreate essential features of complex H–E systems and assess multi-dimensional trade-offs in ecosystem services.102.
Fisheries Science - We examined phytoplankton productivity in Shido Bay, an active oyster farming area in the eastern Seto Inland Sea, Japan, by an in situ 13C method from March 2016 to January... 相似文献
103.
Nagase Mitsutoshi Yi Ruirong Hidaka Fuminori Maeta Kazuhiko Aimi Tadanori Yamaguchi Takeshi Suginaka Katsuaki Morinaga Tsutomu 《Fisheries Science》2010,76(5):885-892
Real-time polymerase chain reaction (PCR) analysis of the 3′-portion of the mitochondrial 16S RNA gene (rDNA) coding sequence
was used to determine flying fish paste in ago-noyaki. We quantified the amount of flying fish paste in ago-noyaki samples using flying fish-specific primers (Tobi16SF3/Tobi16SR) and universal primers (Univ16SF2/Univ16SR2). Using real-time
PCR of standard ago-noyaki, a standard equation was obtained (y = 1.08x − 3.20; R
2 = 0.977). This equation was then used to estimate the relative flying fish paste contents of eight commercially available
ago-noyaki and two similar products. These results verified that the ago-noyaki products that had already been labeled with the E-mark deserved this status. 相似文献
104.
Jimbo Mitsuru Yamashita Hiroshi Koike Kazuhiko Sakai Ryuichi Kamiya Hisao 《Fisheries Science》2010,76(2):355-363
We report herein the presence of a lectin in the scleractinian coral Ctenactis (Fungia) echinata. The lectin bound preferentially to lactose, melibiose, and d-galactose. The purified lectin CecL was composed of several isolectins, and it was found to have a molecular mass of 67.4 kDa
via gel filtration. Glycopeptidase F-treated CecL showed a single band at 32.5 kDa. The mass/charge ratios of the reduced
CecL peaks were equivalent to half those of the native peaks. These results suggest that CecL is composed of two glycosylated
polypeptides linked by interchain disulfide bonds. In a biological activity test using a zooxanthellal culture (Dinoflagellate
Symbiodinium) clonally isolated from Fungia cf. fungites, CecL transformed the flagellated motile form of Symbiodinium into the nonmotile coccoid form, a form equivalent to the symbiotic stage. The activity of CecL on Symbiodinium cells was concentration dependent, and 100 μg/ml CecL arrested Symbiodinium cells in the coccoid form for 5 days. CecL also suppressed the growth of Symbiodinium cells, unlike the octocoral lectin derived from Sinularia lochmodes, which arrests Symbiodinium cells in the coccoid form but does not affect the growth of the coccoid. This result provides further evidence that coral
lectins play a role in symbiont engagement and maintenance in zooxanthellae–coral symbiosis. 相似文献
105.
Kazuhiko Mochida Katsutoshi Ito Kumiko Kono Toshimitsu Onduka Akira Kakuno Kazunori Fujii 《Fisheries Science》2010,76(2):333-341
The effects of organotin compounds on marine organisms, especially on their reproduction, are a continuing source of concern.
We performed full-life-cycle exposure tests of tributyltin oxide (TBTO) at sub-lethal concentrations (0.13, 0.25, 0.5 and
1.0 μg/l) using a marine fish, the mummichog Fundulus heteroclitus, and studied the toxic effects of exposure to TBTO at various life-cycle stages of the fish. The effect of TBTO was initially
studied on sex differentiation and then on spermatogenesis in maturing fish. A mating experiment was performed to determine
the effects of exposure on the fecundity of female fish, fertilization success, and the hatch of the F1 generation. In all experimental groups, TBTO exposure resulted in a tendency toward a male-biased sex ratio and caused a
significant increase in the frequency at which apoptotic cells appeared in the testes. Exposure to 1.0 μg/l TBTO resulted
in a significant decrease in fecundity, but no significant effect was found on the fertilization ratio. Time to hatch and
hatchability of the F1 generation were markedly affected in some exposure groups. These results indicate that long-term exposure of the mummichog
to TBTO affects not only gonadal sex differentiation and spermatogenesis but also spawning and egg quality. 相似文献
106.
Kensuke?Eiki Masayuki?Satake Kazuhiko?Koike Takehiko?Ogata Tadashi?Mitsuya Yasukatsu?OshimaEmail author 《Fisheries Science》2005,71(3):633-638
ABSTRACT: Yessotoxin (YTX) is a shellfish toxin and its contamination in bivalves has seriously damaged shellfish industries. The biogenetic origin of YTX was identified as the dinoflagellate Protoceratium reticulatum (Claparède et Lachmann) Bütschli collected in New Zealand and Yamada Bay, Iwate in Japan. Scallops cultured in Mutsu Bay, Japan, were frequently contaminated with YTX, however, occurrence of P. reticulatum in this bay and YTX production by the local strains have not been investigated. Eight strains of P. reticulatum , isolated from the bay, were cultured in the laboratory, and analyzed by fluorometric high-pressure liquid chromatography and liquid chromatography/mass spectrometry methods for YTX production and composition. All strains tested were confirmed to produce YTX, and none of them produced known YTX analogs. Toxin amount and composition differed from strain to strain. This result is also confirmation of one of the biogenetic origins of YTX in Mutsu Bay. 相似文献
107.
Spawning induction and seed production of Eastern little tuna,Euthynnus affinis (Cantor, 1849), in the post‐ and pre‐spawning seasons by hormonal treatment in a semi‐closed recirculation system with elevated temperature 下载免费PDF全文
Ryosuke Yazawa Yutaka Takeuchi Kenta Satoh Yuri Machida Kotaro Amezawa Naoki Kabeya Goro Yoshizaki 《Aquaculture Research》2017,48(7):3472-3481
We previously established a method for spawning induction in Eastern little tuna (ELT) Euthynnus affinis (Cantor, 1849) by administering a gonadotropin‐releasing hormone analog (GnRHa) during the natural spawning season in Japan (August–October). In order to establish seed production of ELT in the off‐spawning season, we first conducted three spawning induction trials by GnRHa administration from October 2011 to January 2012 using ELT broodstock (2 years old; three females and four males) maintained in a 10‐m3 tank with a semi‐closed recirculation system and static elevated temperature. Average water temperature and daily egg production in three trials lasting 11–15 days were 27.0 ± 0.09°C and 268 173 eggs (Trial 1), 27.0 ± 0.11°C and 277 9098 eggs (Trial 2), and 25.5 ± 0.39°C and 291 113 eggs (Trial 3) respectively. Mean fertilization rate and mean hatching rate were 70.4% and 60.5% (Trial 1), 83.9% and 79.6% (Trial 2), and 62.5% and 57.4% (Trial 3) respectively. We also succeeded in producing ELT larvae in the pre‐spawning season (April–July), although the quantity and quality of larvae produced were inferior to those produced in other calendar months. In trials involving periodic GnRHa administration during the off‐spawning seasons, hatched larvae were obtained in the 10‐m3 tank after six of nine administrations in the 2011–2012 off‐spawning season and in 16 of 19 administrations in the 2012–2013 off‐spawning season. The findings of this study demonstrated that hormonal treatment and thermal control could be used to extend the spawning period in ELT, potentially allowing larval production in the post‐ and pre‐spawning seasons. 相似文献
108.
In vitro assessment of the antiparasitic effect of caprylic acid against several fish parasites 总被引:3,自引:0,他引:3
Noritaka Hirazawa Syun-ichirou Oshima Kazuhiko Hata 《Aquaculture (Amsterdam, Netherlands)》2001,200(3-4):251-258
The antiparasitic effect of caprylic acid against several fish parasites, i.e., the ciliate Cryptocaryon irritans (theronts), monogenean Benedenia seriolae (oncomiracidia and adults), copepod Pseudocaligus fugu (copepodids and adults) and myxosporean Kudoa shiomitsui (spores), was examined by in vitro trials.
Caprylic acid at a concentration of 1 mM had a parasiticidal effect against C. irritans theronts, B. seriolae oncomiracidia and K. shiomitsui spores and a contractile effect against B. seriolae adults, but had no clear effect against P. fugu copepodids and adults. These results suggest that caprylic acid may have an antiparasitic effect against various fish parasites, including parasites classified as monogenea, ciliates and myxosporea. 相似文献
109.
110.
Methane uptake and nitrous oxide emission in Japanese forest soils and their relationship to soil and vegetation types 总被引:1,自引:1,他引:1
Tomoaki MORISHITA Tadashi SAKATA Masamichi TAKAHASHI Shigehiro ISHIZUKA Takeo MIZOGUCHI Yoshiyuki INAGAKI Kazuhiko TERAZAWA Satoshi SAWATA Masanori IGARASHI Hiroshi YASUDA Yasuhiro KOYAMA Yoshihito SUZUKI Nobuyuki TOYOTA Masamichi MURO Masaru KINJO Hirokazu YAMAMOTO Daitaro ASHIYA Yoichi KANAZAWA Tetsu HASHIMOTO Hidetaka UMATA 《Soil Science and Plant Nutrition》2007,53(5):678-691