Water collection efficiency of wick samplers under steady state flow conditions

Wick samplers could be used for measurements of solute transport. Water collection efficiency of wick samplers, defined as the volume of water collected by a sampler divided by the water flux from the root zone, should be close to 100%. We used three wick samplers differing in wall height in Hydric Hapludands under constant rainfall intensity and examined the effects of the rainfall intensity and wall height on the water collection efficiency based on experimental data and a numerical analysis. The water collection efficiency of wick samplers increased with the rainfall intensity and wall height because the increase in both rainfall intensity and wall height resulted in a distribution of the total potential inside the wick sampler close to that outside the wick sampler. Furthermore, the ratio of the cross-sectional area of the drain hole to that of the cylinder must be taken into account in the design of a wick sampler.     

Humus composition of mountain soils in Central Japan with special reference to the distribution of P type humic acid

The central districts of Japan are mountainous areas rising to 3,000 metres which are predominantly covered with forest vegetation. A comprehensive and systematic classification of the soils in this region has not yet been made, but the following soil types have been reported to occur: - 1. 1. Brown forest soils, podzolic soils, black soils and red soils. [Described by OHMASA (14)]

2. 2. Alpine grassland soils and alpine meadow soils. [Described by KUMADA et al. (9)]

3. 3. A series of randzina-like soils with a very restricted distribution. These are derived mainly from limestone and show various degrees of maturity. [Described by KUMADA et al. (8)]

4. 4. Red-yellow soils. These sometimes show a close resemblance to OHMASA's red soils and are found on diluvial plateaux and hills. [Described by KANNO (1)]

5. 5. Paddy soils.

     

Specific gravity of allophane and volcanic ash soils determined with a pycnometer

The determination of the specific gravity of allophane is an interesting and important problem, but it is no exaggeration to say that we have no satisfactory answer to this question in spite of numerous studies. In this note, the specific gravities of allophane, weathered pumices and volcanic ash soil were determined with a pycnometer, and the values compared with those of the other clay minerals and non-volcanic ash soils.     

Characterization of DAX‐8 adsorbed soil fulvic acid fractions by various types of analyses

We investigated the optical absorption properties (A ₄₀₀/C and A ₆₀₀/C values), elemental composition, weight-averaged molecular weight (Mw), and liquid-state carbon-13 (¹³C) nuclear magnetic resonance (NMR) spectroscopy of DAX-8 adsorbed fulvic acid fractions (DAX-8 FAs) in various soils (n?=?36) to establish the general trends in their chemical characteristics. We also compared our results with those of humic acids (HAs) obtained from the same soils used in this study and other published data to discuss the differences between them. Our results clearly indicate that DAX-8 FAs with high carboxyl C content have small Mw and low hydrogen to carbon (H/C) ratio. In addition, DAX-8 FAs with high carbonyl C and alkyl C content have high A ₄₀₀/C values and H/C ratios, respectively. These results strongly suggest that DAX-8 FAs with high aliphatic chemical properties have low carboxyl C content, large Mw and high H/C ratio. There are significant differences in chemical characteristics among the various soil types in almost all data; e.g., DAX-8 FAs from Podzols showed significantly higher A ₄₀₀/C values, larger Mw, higher carbonyl C and O-aryl C content than those obtained from Andosols. However, these two C functional groups are relatively low values in the total C content among all soil types, suggesting that DAX-8 FAs may exhibit only small differences in chemical properties among the various soil types. The comparison with published data regarding soil HAs shows that DAX-8 FAs are characterized by smaller Mw; lower C, H, and nitrogen (N); higher oxygen (O) content; higher O/C; lower O/H ratios; higher carboxyl C content; and lower aryl C content in total C.     

Relationship between cation-exchange capacity and degree of maturity of city refuse composts

Abstract

An attempt was made to estimate the degree of maturity of city refuse composts by measuring their cation-exchange capacity (CEC).

The CEC of the city refuse compost increased for the first 7 days after commencement of the fermentation process, decreased for the next 2 days, and then increased again gradually up to the end of the piling period.

A highly significant negative correlation was noted between the CEC and C/N ratio of the city refuse composts (r=-0.903***). Regression analysis yielded the relationship: In CEC=7.02-1.02 In C/N

The CEC values of the city refuse composts, which were considered to have been sufficiently matured for application, were greater than about 60 me/ 100 g of ash-free material.     

Factors Influencing the Determination of Microbial Biomass-Nitrogen in Submerged Soil

In a previous paper (1), a modification of the chloroform fumigation method (2) was proposed for estimating microbial biomass-nitrogen (N) in submerged soil. It was found that a large part of the living bacteria in the submerged soil was killed within about 12 h of the fumigation and was actively mineralized by subsequent anaerobic incubation.

In this paper, the following factors which influence the estimated amount of microbial biomass-N were examined: a) inoculation to fumigated soil, b) duration of anaerobic incubation, c) storage and sieving pretreatments of soil, and d) effect of fumigation on soil organic matter.     

Change of antibody levels to ferritin in the sera of foals after birth: Possible passive transfer of maternal anti‐ferritin autoantibody via colostrum and age‐related anti‐ferritin autoantibody production

Antibody (immunoglobulin G (IgG), IgM or IgA) levels relative to ferritin in six foal sera (three male and three female) after birth (day 0 and 2, 6, 10, 20, 28, 36, 40, 52 and 56 weeks of age) were semi‐quantitatively measured with normalization with antibody activity to ferritin in one adult horse serum. After addition of horse spleen ferritin to the serum sample, the complex formed between antibodies to ferritin in the serum and ferritin was co‐immunoprecipitated using antibody to horse spleen ferritin. Antibody classes of the co‐immnoprecipitate were detected with antibodies specific for horse IgG, IgM or IgA heavy chain. Six adult horse serum samples were found to have ferritin‐binding activities in all immunoglobulin classes examined. Although ferritin antibody activities (IgG, IgM and IgA) were scant in the foal sera before sucking colostrum (day 0), their activities increased at 2 weeks of age. IgG antibodies showed a biphasic response and IgM antibody activity increased up to 40 weeks of age. Antibody (IgG, IgM and IgA) activities to ferritin in three colostrum samples were significantly higher than in adult horse serum samples. These results demonstrate that antibody to ferritin in foal serum is derived from colostrum after birth and is produced thereafter.     

Genetic population structure of the Pacific bluefin tuna Thunnus orientalis and the yellowfin tuna Thunnus albacares in the North Pacific Ocean

The genetic population structure of the Pacific bluefin tuna (PBF) Thunnus orientalis and the yellowfin tuna (YFT) T. albacares in the North Pacific Ocean was investigated. The polymorphism of microsatellite (SSR) loci and sequences of mitochondrial DNA control region (mtCR) were analyzed for 71 samples of PBF from Japan and Mexico and 45 samples of YFT from Japan and Panama. In the SSR analyses, both single-locus (?0.010 to 0.008 in PBF and ?0.023 to 0.020 in YFT) and global multilocus (0.003 in PBF and ?0.002 in YFT) F _ST values among the geographic populations were low and not significant in these species. In the mtCR analyses, neither the neighbor-joining tree nor the minimum spanning network showed genetic differentiation among the geographic populations in each species. The pairwise F _ST values among the geographic populations of them (?0.005 in PBF and ?0.020 to ?0.014 in YFT) were low and not significant. Our SSR and mtCR data suggested that genetic differentiations were not evident among the eastern and western populations in the North Pacific Ocean either in PBF or in YFT. Mismatch distributions, demographic parameters, and neutrality tests suggested that sudden population expansion of PBF and YFT in the North Pacific Ocean occurred 628,000–731,000 and 450,000–525,000 years ago, respectively.     

Genetic analysis of ion-beam induced extremely late heading mutants in rice

Two extremely late heading mutants were induced by ion beam irradiation in rice cultivar ‘Taichung 65’: KGM26 and KGM27. The F₂ populations from the cross between the two mutants and Taichung 65 showed clear 3 early: 1 late segregation, suggesting control of late heading by a recessive gene. The genes identified in KGM26 and KGM27 were respectively designated as FLT1 and FLT2. The two genes were mapped using the crosses between the two mutants and an Indica cultivar ‘Kasalath’. FLT1 was located on the distal end of the short arm of chromosome 8. FLT2 was located around the centromere of chromosome 9. FLT1 might share the same locus as EHD3 because their chromosomal location is overlapping. FLT2 is inferred to be a new gene because no gene with a comparable effect to that of this gene was mapped near the centromere of chromosome 9. In crosses with Kasalath, homozygotes of late heading mutant genes showed a large variation of days to heading, suggesting that other genes affected late heading mutant genes.     

Effect of wood species on thermal flow behavior and physical properties of thermoplastic moldings

The thermoplastic flow behavior of cedar flour steamed at different temperatures in the range of 160–220°C was measured using a rheometer and compared with that of beech flour. The temperature at which the cedar flour starts to flow was approximately 70°C higher than that of beech flour, and the cedar flour exhibited low flowability. Furthermore, thermoplastic moldings were prepared from cedar and beech flours, and their physical properties were examined. Similar to the case of beech, a resin-like molding with a density of approximately 1.45?g/cm³ was obtained from the cedar flour steamed at 180°C or higher, and it was revealed by SEM observation that in these moldings wood flour particles adhere to each other. The specific bending strength was maximum for the moldings obtained from 180°C-steamed flour for both types of wood.