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1.
The root parameters of forest trees can be indicators of a changing environment. We summarize the results of root studies
with regard to the effects of acidifying pollutants, especially soil acidification and aluminum toxicity, on various root
parameters of Japanese forest trees under experimentally controlled conditions. All root parameters such as biomass, morphology,
nutritional status, and physiology can be regarded as indicators, because, under laboratory conditions, root responses occur
prior to the responses in the aboveground parts. However, considering the conditions of forest sites, the nutritional status
and physiological changes are better indicators of soil acidification and Al stress than the biomass and morphological response.
The currently available data suggest that the most important indicator is the Ca/Al molar ratio in roots of Japanese tree
species. In order to predict and detect the initial effects of soil acidification, we postulate that the specific root response
to the Ca/Al molar ratio of tree roots should be considered as a parameter for use in long-term forest monitoring sites. 相似文献
2.
Kyotaro Noguchi Tadashi Sakata Takeo Mizoguchi Masamichi Takahashi 《Journal of Forest Research》2005,10(6):435-441
Fine roots are a key component of forested ecosystems, but available information is still limited. This study examined the
production and mortality of fine roots less than 1 mm in diameter in a Japanese cedar (Cryptomeria japonica D. Don) plantation located on the Kanto Plain in central Japan. We used a minirhizotron technique in combination with soil
coring, and collected data for 1 year (May 2002–May 2003). Fine root production and mortality were determined from changes
in the lengths of individual fine roots on minirhizotron tubes. Both fine root production and mortality rates were greater
in the upper soil than in lower soil levels. Both rates were seasonal, with higher values in summer than in winter; this trend
was more pronounced in upper soil levels. These results suggest that environmental conditions, such as temperature or soil
properties, affect the production and mortality rates of fine roots. Fine root production and mortality occurred simultaneously,
and their rates were similar, which may have led to unclear seasonal changes in fine root standing crop estimates. Soil coring
indicated that the fine root biomass of this stand was about 120 g m−2, of which 40% was from Japanese cedar. The estimated rates of dry matter production and mortality of total fine roots, including
understory plants, were both approximately 300 g m−2 year−1. 相似文献
3.
Wakita T 《Journal of agricultural and food chemistry》2011,59(7):2938-2942
Dinotefuran, (RS)-1-methyl-2-nitro-3-(tetrahydro-3-furylmethyl)guanidine, is a neonicotinoid insecticide developed by Mitsui Chemicals Agro. Dinotefuran provides a tetrahydrofuran (THF) moiety distinct from other neonicotinoids with a chloropyridine or chlorothiazole ring, which is considered to be an essential structural element for the neonicotinoid action. The molecular design strategy based on acetylcholine ester moiety as a lead structure has successfully led to the discovery of dinotefuran with the cyclic ether THF functional group. The unique chemical and excellent biological properties and favorable toxicological profile make dinotefuran available for pest management in wide range of crops with a variety of application methods. 相似文献
4.
Toshisuke Maruyama Fumikazu Noto Tsuyoshi Takahashi Kimihito Nakamura Takeo Onishi 《Paddy and Water Environment》2011,9(2):267-274
An evaluation of the nitrogen pollution load potential (NPLP) arising from several sewage treatment systems in the Tedori
River Alluvial Fan Area was evaluated by determining the removal percentage of nitrogen as a result of sewage treatment and
amounts of nitrogen lost from the different treatment systems. These data were applied to the entire area resulting in an
estimated total NPLP of 734 t year−1 (103 kg year−1), of which 548 t year−1 discharges into the Japan Sea and so does not contribute to the pollution of the environment considered here. The residual
186 t year−1 of the NPLP has a high probability of causing groundwater or downstream pollution, with 58% of the NPLP being contributed
from septic tanks not connected to public sewage systems. Rural sewage system accounted for about 18% of the NPLP. Material
directly flowing into the middle stream of the Tedori River together with sewage water from small companies and untreated
sewage water from local family dwellings made up about 3–12% of the NPLP. To improve water quality due to sewage effluent,
it is essential to increase the number of connections to public sewage systems from septic tanks. 相似文献
5.
Abul Hasnat Md. Shamim Md. Harunor Rashid Khan Takeo Akae 《Paddy and Water Environment》2009,7(2):95-103
Severe acidifications in acid sulfate soils (ASSs) have occurred worldwide due to sulfuric acidity, which requires sustainable
measures for their reclamation. Accordingly, an incubation study was conducted with the topsoil of two different ASSs (Cheringa
and Badarkhali) to evaluate the effects of basic slag (BS; size <1 mm, pH 9.6, Ca 20.8%, Mg 9.8%, etc.), on reduction of acidity
and changes in exchangeable cations. It is noted that BS is a byproduct of steel industry in Bangladesh and can be collected
almost free of charge. These soils received BS at the rate of 0 (T0), 11 (T1), 22 (T2) and 33 (T3) t ha−1 under various moisture regimes (saturated condition M1,, i.e., 100% moisture content, wetting–drying cycles of 100 and 50% moisture M2, and moisture at field condition M3, i.e., 50%). The impacts of these treatments on some selected parameters in these soils were studied within 180 days of incubation.
The application of BS was found to increase the pH of soils from 3.6 to 5.1 for Cheringa, 3.9 to 5.2 for Badarkhali soils
at the end of incubation. These increments were more striking with the highest doses of BS under saturated moisture conditions
in both of the soils. The ECe of the soils was not much influenced by the application of BS regardless of time. The treatments
exerted significant (P ≤ 0.05) effects on exchangeable cations in different periods of incubation. The striking changes were recorded for the rate
of increments of Ca2+ and Mg2+, which were about 2–3 times higher for Ca and more than 2 times higher for Mg2+ compared with the control after 180 days of incubation. These results suggest that the application of BS not only increased
the Ca2+ to the higher amount than that of the increment of Mg2+ in the soils, but also improved one of the important criteria of Ca2+ and Mg2+ ratio in the soils. 相似文献
6.
Masahiro Hosono Shigeki Sugawara Atsushi Matsuda Takeo Tatsuta Yasuhiro Koide Imtiaji Hasan Yasuhiro Ozeki Kazuo Nitta 《Fish physiology and biochemistry》2014,40(5):1559-1572
Rhamnose-binding lectin (RBL) is one of the animal lectin categories which take part in the innate immune responses of fish. Osmerus lanceolatus lectin (OLL) from shishamo smelt eggs is an RBL composed of two tandem-repeated domains, both of which are considered to be a carbohydrate-recognition domain. SAL, catfish (Silurus asotus) egg RBL composed of three domains, binds to Burkitt’s lymphoma Raji cells through globotriaosylceramide (Gb3) carbohydrate chain and to reduce cell size and growth by altering membrane composition without causing cell death. In this experiment, we tried to compare the binding effects of these two RBLs on Raji cells. Flow cytometric and fluorescence microscopic analyses revealed that OLL also directly bound to and shrunk Raji cells with ten times less reactivity than SAL but reduced cell growth with decreasing cell viability. Anti-Gb3 antibody completely blocked the binding of SAL to Raji cells but not that of OLL. In addition, the direct bindings of OLL and SAL to Raji cells were comparably inhibited by melibiose, but lactose was more effective inhibitor for the binding of OLL than that of SAL. These results suggest that OLL has slightly different cell-binding property compared with SAL and binds not only to Gb3 but also to the other carbohydrate receptor-bearing β-galactoside chains. The quantitative RT-PCR analysis revealed that SAL induced the expression of TNF-α but not of IFN-γ, IL-1β, and IL-10. Thus, SAL-induced cytostatic effect on Raji cells might be partially caused by TNF-α-mediated signaling pathway. 相似文献
7.
Shivashankara KS Isobe S Al-Haq MI Takenaka M Shiina T 《Journal of agricultural and food chemistry》2004,52(5):1281-1286
Greenhouse-grown tree ripe (TR) and mature green (MG) mangoes (cv. Irwin) were exposed to high electric field treatment before 20 and 30 days of storage at 5 degrees C. MG fruits were allowed to ripen at room temperature after low-temperature storage. Fruit physical quality attributes, ascorbic acid, carotene, quercetin, total phenols, and antioxidant capacity were estimated before and after the storage period. Antioxidant capacity of fruit juice was estimated using the ferric reducing antioxidant power (FRAP) assay. Fruit firmness decreased significantly during storage. Titratable acidity decreased 20 days after storage. Total soluble solids did not change during storage. Antioxidant capacity of fruits remained unchanged up to 20 days of storage period and decreased thereafter. Total phenol and carotenes increased during storage. Antioxidant capacity of fruits was significantly correlated only to ascorbic acids. Peel color and carotenes were higher in TR fruits, whereas titratable acidity and firmness were higher in MG fruits. There was no significant difference in other parameters between the stages of picking. Electric field pretreatment affected the respiration and antioxidant capacity of TR fruits and did not have any significant affect on other parameters. TR mangoes of cv. Irwin are more suitable for low-temperature storage and can be successfully stored for up to 20 days at 5 degrees C without any significant losses in functional properties and quality attributes. 相似文献
8.
Urbanization is expanding in and around small to medium-sized cities as well as in large cities, and the expansion includes low-lying areas where the flood risk is high. Flood risk in small watersheds has been evaluated using precise mathematical models. However, these models cannot be applied to larger basins due to the complexity of data collection and analysis. As a result, quantitative evaluations of flood risk at macro scales and the flood-prevention function of paddies around urban areas have not been made. This paper proposes a method and an index that can be used to evaluate the flood-prevention function of paddies on a regional scale. In addition, the use of this system for basin-wide management is illustrated by an example for the Kinu and Kokai rivers, which are tributaries of the Tone River of Japan. The applicability of the approach is evaluated using data from a major flood that occurred in the study area. 相似文献
9.
10.
Kohara Y Minematsu T Aikawa T Kanai Y Tajima A 《The Journal of reproduction and development》2008,54(3):221-224
The objective of this study was to establish a protocol for generating karyoplasts that can be used to produce somatic nuclear transferred gonadal germ cells (snt-GGCs) in domestic chickens. Karyoplasts were produced by centrifuging cultured fibroblasts from 10-day-old chick embryos at 10,000 x g in the presence of 1.0 microg/ml cytochalasin B. The number of karyoplasts was significantly (P<0.05) higher and the diameters of the karyoplasts were significantly (P<0.05) smaller when fibroblasts were centrifuged for 60 min than for 10 or 30 min. It was possible to generate snt-GGCs by electrofusion of GGCs with karyoplasts produced from cryopreserved or serum-starved fibroblasts. These results indicate that karyoplasts generated from 10-day-old chick embryos can be used to produce snt-GGCs even after cryopreservation and serum starvation of the fibroblasts. 相似文献