Greenhouse gas emissions after a prescribed fire in white birch-dwarf bamboo stands in northern Japan,focusing on the role of charcoal

Forest fires affect both carbon (C) and nitrogen (N) cycling in forest ecosystems, and thereby influence the soil–atmosphere exchange of major greenhouse gases (GHGs): carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O). To determine changes in the soil GHG fluxes following a forest fire, we arranged a low-intensity surface fire in a white birch forest in northern Japan. We established three treatments, having four replications each: a control plot (CON), a burned plot (BURN), and a plot burned with removal of the resulting charcoal (BURN-CHA). Soil GHG fluxes and various properties of the soil were determined on four or five occasions during a period that spanned two growing seasons. We observed increased concentrations of ammonium-N (NH₄-N) in BURN and BURN-CHA after the fire, while nitrate–N (NO₃-N) concentration was only increased in BURN-CHA after the fire. The soil CO₂ flux was significantly higher in CON than in BURN or BURN-CHA, but there was no difference in soil CH₄ uptake between the three treatments. Moreover, the N₂O flux from BURN-CHA soil was slightly greater than in CON or BURN. In BURN-CHA, the soil N₂O flux peaked in August, but there was no peak in BURN. We found temporal correlations between soil GHG fluxes and soil variables, e.g. soil temperature or NO₃-N. Our results suggest that environmental changes following fire, including the increased availability of N and the disappearance of the litter layer, have the potential to change soil GHG fluxes. Fire-produced charcoal could be significant in reducing soil N₂O flux in temperate forests.     

Effects of the feeding of wild Yeso sika deer (Cervus nippon yesoensis) on the prevention of damage due to bark stripping and the use of feeding sites

Feeding sites for wild Yeso sika deer around Lake Akan, Japan, were established. Effects on the number of deer using the feeding sites, the prevention of bark stripping damage, the amount of feeding, and eating time in a 5‐year period (1999–2003) were evaluated. The number of deer using feeding sites increased with years during the feeding period. The damaged tree ratio after the initiation of feeding markedly decreased compared with 16.5% before the initiation of feeding. After the start of feeding, there were no trees with damage the entire circumference. According to tree species, the number of damaged trees of Ulmus laciniata Mayr as a percentage of all investigated trees was high (5.2%). The total amount of beet pulp feeding increased with the feeding year, showing 4.5‐fold increase. At feeding sites in deer culling, eating behavior was observed during the night. The preventive effects on bark stripping damage continued during the 5‐year feeding period. However, with the course of feeding years, the number of deer using feeding sites and the level of feeding increased.     

Regulation of skin color in ‘Aki Queen’ grapes: Interactive effects of temperature,girdling, and leaf shading treatments on coloration and total soluble solids

The interactive effects of temperature, girdling, and leaf shading treatments on the total soluble solids (TSS) content and coloration of ‘Aki Queen’ (Vitis labruscana) grapes were investigated. The TSS contents of berries were significantly higher in girdled plants than in plants with shaded leaves. Anthocyanin accumulation was greater at lower temperature (21 ± 2 °C) than at higher temperature (31 ± 2 °C) in both control and girdled plants, but anthocyanins did not accumulate in plants with shaded leaves at either temperature. Temperature did not influence TSS content. These results suggest that a high enough TSS content promotes anthocyanin synthesis under low temperature during maturation of ‘Aki Queen’ grape.     

Effect of CO2 enrichment on carbon and nitrogen interaction in wheat and soybean

Effect of CO₂ enrichment on the carbon-nitrogen balance in whole plant and the acclimation of photosynthesis was studied in wheat (spring wheat) and soybean (A62-1 [nodulated] and A62-2 [non-nodulated]) with a combination of two nitrogen application rates (0 g N land area m^-2 and 30 g N land area m^-2) and two temperature treatments (30/20°C (day/night) and 26/16°C). Results were as follows.

1. Carbon (dry matter)-nitrogen balance of whole plant throughout growth was remarkably different between wheat and soybean, as follows: 1) in wheat, the relationship between the amount of dry matter (DMt) and amount of nitrogen absorbed (Nt) in whole plant was expressed by an exponential regression, in which the regression coefficient was affected by only the nitrogen application rate, and not by CO₂ and temperature treatments, and 2) in soybean the DMt-Nt relationship was basically expressed by a linear regression, in which the regression coefficient was only slightly affected by the nitrogen treatment (at 0N, DMt-Nt balance finally converged to a linear regression). Thus, carbon-nitrogen interaction in wheat was strongly affected by the underground environment (nitrogen nutrition), but not by the above ground environment (CO₂ enrichment and temperature), while that in soybean was less affected by both under and above ground environments.

2. The photosynthetic response curve to CO₂ concentration in wheat and soybean was less affected by the CO₂ enrichment treatment, while that in wheat and soybean (A62-2) was affected by the nitrogen treatment, indicating that nitrogen nutrition is a more important factor for the regulation of photosynthesis regardless of the CO₂ enrichment.

3. Carbon isotope discrimination (..:1) in soybean was similar to that in wheat under ambient CO₂, while lower than that in wheat under CO₂ enrichment, suggesting that the carbon metabolism is considerably different between wheat and soybean under the CO₂ enrichment conditions.     

Effects of press closing time on mat consolidation behavior during hot pressing and on linear expansion of particleboard

Mat consolidation behavior was investigated at various press closing times (PCTs) using hinoki (Japanese cypress) particle mats. The temperature in the core layer of the mat, press pressure, and platen distance were measured. At the plateau stage during hot pressing, the core temperature decreased with increasing PCT. The core temperature did not increase before the platen distance equaled the target board thickness in the PCT range of 4–50 s and rose slightly when the PCT exceeded 100s. There was a linear relation between the logarithm of PCT and the maximum press pressure. The density profile across board thickness was strongly affected by the PCT. As the PCT increased, the position of the peak density (PD) moved toward the core layer as the PD itself decreased. The effect of PCT on the linear expansion (LE) of the board is discussed in relation to the density profile. There was no difference in LE after high relative humidity treatment in the PCT range 4–50s. LE appeared to be related to the low density and the precured region of the board surface. The LE after drying treatment was around –0.1%, and the thickness swelling after high relative humidity and drying treatments increased with increasing PCT.Part of this report was presented at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 1988     

Coniferyl aldehyde dimers in dehydrogenative polymerization: model of abnormal lignin formation in cinnamyl alcohol dehydrogenase-deficient plants

The enzymatically dehydrogenative polymerization of coniferyl aldehyde and coniferyl alcohol was studied to understand lignins in cinnamyl alcohol dehydrogenase (CAD)-downregulated plants. The sample dimers were prepared by polymerization under three reaction systems (coniferyl alcohol, coniferyl aldehyde, and their combination) with horseradish peroxidase/H₂O₂ under the conditions of limited reaction time. In addition, the residual amount of substrate in each reaction was determined at specified time intervals. In the reaction system of coniferyl aldehyde, the 5-5-type dimer was formed in preference to- and-5 dimers; in the reaction system of coniferyl alcohol the-5 dimer was preferentially formed. Furthermore, it was revealed when quantifying dimers among reaction systems that the total dimer formation capability of coniferyl alcohol clearly surpassed that of coniferyl aldehyde. However, the dimers cross-coupled with coniferyl alcohol and coniferyl aldehyde were formed in amounts not accounted for by the difference seen in dimer formation abilities with the two substrates.Part of this paper was presented at the 49th Annual Meeting of the Japan Wood Research Society, Tokyo, April 1999     

Needle life span,photosynthetic rate and nutrient concentration of Picea glehnii,P. jezoensis and P. abies planted on serpentine soil in northern Japan

We investigated the adaptation of three spruce species (Picea glehnii Masters, P. jezoensis Carr. and P. abies Karst.) to growth in northern Japan on serpentine soils (characterized by high concentrations of heavy metals and Mg, a low Ca/Mg ratio and low fertility) and fertile brown forest soils. Among species, seedling survival on serpentine soil was highest in P. glehnii. Shoot growth of P. glehnii was similar whether grown on serpentine or brown forest soil, whereas shoot growth of the other species was significantly less on serpentine soil than on brown forest soil. On serpentine soil, needle life span of P. glehnii was at least 3 years longer than that of the other two species. Needle area per shoot of P. glehnii was significantly higher on serpentine soil than on brown forest soil up to a shoot age of 8 years. In all three species, light-saturated photosynthetic rate (Pmax) decreased with needle age independently of soil type. However, on serpentine soil, Pmax in P. glehnii was higher, particularly in older needles, than in the other species. Furthermore, on serpentine soil, needle concentrations of nitrogen and phosphorus were higher in P. glehnii than in the other species. We conclude that P. glehnii is better adapted to serpentine soil than P. jezoensis and P. abies at least in part because of its greater needle life span and higher needle nutrient concentrations.     

First detection of adiaspiromycosis in the lungs of a deer

Adiaspiromycosis is a pulmonary infection caused by the soil fungi, Emmonsia crescens and E. parva. It primarily affects small mammals and can range from an asymptomatic condition to fatal disseminated disease. We detected a granuloma containing fungal spherules, which were morphologically consistent with the adiaspores of E. crescens in the lungs of a female Hokkaido sika deer. This is the first reported case of adiaspiromycosis involving a cervid in the world.     

Studies of the New Herbicide KIH-6127. Part II. Synthesis and Herbicidal Activity of 6-Acyl Pyrimidin-2-yl Salicylates and Analogues against Barnyard Grass

The method reported previously (Part I) was employed to prepare a variety of novel 6-acylsalicylates as key intermediates. 6-Acylpyrimidin-2-yl salicylates (2-acyl-6-[(4,6-disubstituted pyrimidin-2-yl)oxy]benzoate derivatives: Type 1), the closely related phthalide compounds (3-alkyl-7-[(4,6-dimethoxypyrimidin-2-yl)oxy]phthalide derivatives: Type 2) and the ketal derivatives of 2-acyl-6-[(4,6-dimethoxypyrimidin-2-yl)oxy]benzoates (Type 3) were synthesized and their herbicidal activities measured. Methyl 2-acetyl-6-[(4,6-dimethoxypyrimidin-2-yl)oxy]benzoate gave excellent control of barnyard grass with a promising profile as a prototype rice herbicide.