Proton Budgets of Forest Ecosystems on Volcanogenous Regosols in Hokkaido,Northern Japan

The proton budgets of deciduous and coniferous forest ecosystems on volcanogenous regosols in Hokkaido, northern Japan, were studied by measuring the biogeochemical fluxes (atmospheric deposition, canopy leaching, vegetation uptake and leaching from soil) at each site during a three year period. The proton budgets were developed for individual compartments of the ecosystem: vegetation canopy, organic and mineral soil layers. At both sites, atmospheric S deposition was the dominant proton source in the vegetation canopy. In organic horizons, dissociation of weak acids (bicarbonate and/or organic acids) and vegetation uptake of base cations were the dominant proton sources, and the net mineralization of base cations was the dominant proton sink. Atmospheric acid deposition was almost neutralized in the forest canopy and organic horizon. At both sites, weathering and/or ion exchange of base cations and protonation of weak acids (mainly bicarbonate) were the dominant proton sinks in the mineral soil. In both organic and mineral soil, internal proton sources (mainly vegetation uptake of base cations and dissociation of weak acids) exceeded external proton sources, indicating that acid deposition was not the main driving force of soil acidification in the studied forest ecosystems.     

Seasonal Dynamics of Biogeochemical Proton and Base Cation Fluxes in a White Birch Forest in Hokkaido, Japan

Biogeochemical proton and base cation fluxes in a 30-year old white birch forest composed of Dystric Cambisols in northern Hokkaido, Japan were estimated using data on atmospheric deposition (AD), throughfall (TF), stemflow (SF), and discharge from soils (DS) and plant uptake (UP) from early June to November 1999. In the monitoring period, proton flux was 0.20kmol_cha^?1 for AD, 0.07 for TF+SF, and 0.03 for DS, indicating that atmospheric acid input was neutralized through plant and soil. Base cation flux was 1.29 for AD, 1.23 for TF+SF, and 0.99 for DS and plant base cation uptake was 2.14, indicating that the soil was the major source of base cation for plant. However, these seasonal fluxes showed various trends. Cumulative base cation flux in TF+SF showed constant increase trend during the whole period, which was similar to AD. Proton flux in AD jumped once just after a heavy rain of 255mm for 8 days at the end of July. Trends for the proton and base cation fluxes in TF plus SF were similar to that of AD. Although proton and base cation fluxes of DS were not found until middle July because of vegetation uptake and no flow, both fluxes increased suddenly after the heavy rain in July. After August, the base cation and proton fluxes in the DS increased continuously, due to the lack of plant uptake and intermittent rainfall. In this study, it is clear that plant activity and water flow are very important driving force for seasonal dynamics of biogeochemical cycling.     

Arsenic Background Concentrations in Surface Soils of Kavala Area, Northern Greece

A total of 65 surface (0–20 cm) soil samples were collected in an effort to estimate the arsenic background values in Kavala area, Northern Greece. Arsenic was extracted by HNO₃ from the <200?µm grain size fraction, and its concentrations were determined in all samples by inductively coupled plasma–mass spectrometry. Arsenic concentrations were log-transformed, and log-normal probability plots (Q–Q plots) were generated. The geochemical background was calculated as the values that lie between g/d and g?×?d (g, geometric mean; d, geometric standard deviation), which are 3.5 and 25.8 mg kg^?1, respectively. The baseline value (g) was 9.5 mg kg^?1. With the aid of GIS software, arsenic geochemical maps of the study area were created. The majority of the arsenic elevated concentrations were found in the proximity of the industrialized zone of Kavala.     

Long-Term Monitoring Study on Rain, Throughfall, and Stemflow Chemistry in Evergreen Coniforous Forests in Hokkaido, Northern Japan

Long-term study on acid precipitation monitoring at suburban forests in Sapporo city showed that bulk precipitation pH were below 4.8 in recent years. Throughfall and stemflow chemistry for two main coniferous species (Abies sachalinensis and Picea jezoensis) showed different regime for pH and element deposition. The mean annual pH values of throughfall and stemflow in Picea stand were 1.0 to 1.3 units higher than that of rain collected outside the forest. In contrast, mean annual pH of throughfall and stemflow in Abies stand were 0.3 to 0.5 units higher than that of rain. Mean annual inorganic nitrogen input via throughfall and stemflow were estimated 0.41±0.11 gN/m²/yr in Abies stand, 0.44±0.13 gN/m²/yr in Picea stand. Cation input via throughfall, especially for K, in Picea stand was 1.4 times as large as that in Abies stand. Mean annual input of S in both stands was the same level. The possible effects on surface soil properties and nutrient cycling in northern evergreen conifers was discussed.     

The protection of ecosystems and landscapes in Hokkaido,Japan

Hokkaido is the least densely populated of the major islands of Japan and was colonized by the Japanese only in the nineteenth century. There is therefore proportionately more wild land than elsewhere in the nation, and 712,393 ha are designated as National Parks, quasi-National Parks, or Prefectural Parks. These are zoned into three categories, each with varying degrees of development control. Among the protected biota are virgin woodlands of Fagus crenata in the south-west, and pristine Picea-Abies forests in the central mountains of the island. The latter hold relict populations of the Ezo Brown Bear (Ursus arctos yezoensis). Coastal parks are important sites for many species of sea-birds and sea-mammals. Increasing numbers of visitors in most seasons, but especially in summer, combined with the prospect of the increased accessibility of Hokkaido from Honshu, will increase the pressure upon many areas of wild terrain, while industrial and agricultural development are bringing about a decline in the environmental quality of some parts of the island.     

Organic Sulfur and the Retention of Nutrient Cations in Forest Surface Soils

Sulfur and cation transformations were studied in A-horizon soils from 9 plots in Deer Run State Forest (DRSF) in southeastern Missouri on two dates, and from 27 plots of the Missouri Ozark Forest Ecosystem Project (MOFEP) near DRSF, seasonally for three years. The DRSF plots were chosen based on history of timber harvest; 2-3 yr and 8-10 yr post clear-cut, with controls about 40 yt post cut. Total C and S, organic sulfur (OS), exchangeable K+ and Mg2+, and rates of microbial OS production varied by season and year in surface soils from MOFEP plots. Exchangeable K+ concentrations were correlated with total C, total S, and OS. In clear-cut DRSF A-horizon soils, OS production was greatly reduced (p < 0.05) compared with controls. Exchangeable K+ and Mg2+ also were much lower in soils from clear-cut plots than in soils from control plots (p < 0.01). Cation exchange for OS compounds with sulfhydryl groups was only marginally greater than for organic matter of similar structure with no sulfhydryl groups. Overall, litter input appears to be a key to maintaining long-term surface soil OS, K+, and Mg2+ concentrations.     

苏北低山丘陵区典型性森林土壤健康评价研究

以苏北低山丘陵区6种典型性森林植被下土壤为研究对象,通过野外调查与室内分析,在系统调查和分析土壤形态、物理、化学、酶活性特征以及物种多样性的基础上,运用土壤学知识和专家经验,构建了适合苏北山丘区森林土壤健康评价指标体系;应用不同类型的评分函数方程,对各评价指标数值进行隶属度处理,并基于SPSS软件对所获得数据进行差异性检验和相关分析,确定各项指标的权重;最后通过加权综合法,建立森林土壤健康指数,对该地区不同林分下土壤健康状况进行评价。     

Vegetation development patterns on skislopes in lowland Hokkaido, northern Japan

The Japanese montane zones are usually covered with well-developed forests, and most ski resorts are constructed there. Therefore, the construction of skislopes requires the destruction of forest ecosystems. To detect vegetation development patterns on skislopes, I assessed vegetation on seven skislopes in the lowland of Hokkaido Island, Japan, using 155 2 m×2 m plots. The surrounding vegetation was mostly consisted of broad-leaved forests with a floor of dwarf bamboo, Sasa senanensis. The skislopes were established 5-28 years before the surveys by scraping off the topsoil and subsequent artificial seeding. The data of vegetation analyzed by TWINSPAN resulted in six different grassland types: (A) Miscanthus sinensis-Hypochaeris radicata, (B) introduced herbs with low richness, (C) introduced herbs, (D) Artemisia montana, (E) M. sinensis-Pueraria lobata-A. montana, and (F) Solidago gigantea var. leiophylla. H. radicata and S. gigantea var. leiophylla were alien species. Vegetation dominated by introduced grasses for erosion control, such as Dactylis glomerata and Poa pratensis, should be initial vegetation on the skislopes. Most tree pioneer species established in the vegetation type A, that was most natural vegetation in the skislopes. Type A seemed to proceed from types B and C, and species richness was the highest. Therefore, this type should be preferable for the management and restoration of skislope vegetation. Type D established on newer skislopes, while types E and F established on older skislopes. Results including detrended correspondence analysis suggested that those vegetation types D-F proceeded to distorted succession, i.e. biological invasion changed native successional sere. Based on these results, I recommended that the restriction of alien invasion and careful monitoring on M. sinensis grasslands are required to restore the natural vegetation.     

On the volcanic ash soil in Tokachi District,Hokkaido Island,Japan

In Japan, most of the paddy fields are laid out on alluvial plain while other land crop fields are developed on plateau. The greater part of the latter ccnsists of volcanic ash soils.     

日本北海道农村生态系统中N循环研究

This study of Mikasa City in 2001, which analyzed N flow between N production and N load in seven agricultural and settlement subsystems, i.e., paddy, onion, wheat, vegetable, dairy, chicken, and citizen subsystems, aimed to compare N flow in each subsystem, to determine the main sources of the N load, and to evaluate the influence of agricultural production and food consumption on N cycling in a rural area. The results showed that in Mikasa city, 38.5% of the N load came from point sources and the remainder from non-point sources with intensive vegetable farming imparting a serious N load. Because of the internal N cycling in the dairy subsystem, chemical fertilizer application was reduced by 70.2%, and 23.72 Mg manure N was recycled to the field; therefore, the N utilization efficiency was raised from 18.1% to 35.1%. If all the manure N in the chicken subsystem was recycled, chemical fertilizer application would be reduced by 8.1% from the present level, and the point sources of N pollution would be reduced by 20.8%.     

Nitrous oxide emissions and nitrogen cycling in managed grassland in Southern Hokkaido,Japan

Abstract

Nitrous oxide (N₂O) emissions were measured and nitrogen (N) budgets were estimated for 2?years in the fertilizer, manure, control and bare plots established in a reed canary grass (Phalaris arundinacea L.) grassland in Southern Hokkaido, Japan. In the manure plot, beef cattle manure with bark was applied at a rate of 43–44?Mg fresh matter (236–310?kg?N)?ha^?1?year^?1, and a supplement of chemical fertilizer was also added to equalize the application rate of mineral N to that in the fertilizer plots (164–184?kg?N?ha^?1?year^?1). Grass was harvested twice per year. The total mineral N supply was estimated as the sum of the N deposition, chemical fertilizer application and gross mineralization of manure (GMm), soil (GMs), and root-litter (GMl). GMm, GMs and GMl were estimated by dividing the carbon dioxide production derived from the decomposition of soil organic matter, root-litter and manure by each C?:?N ratio (11.1 for soil, 15.5 for root-litter and 23.5 for manure). The N uptake in aboveground biomass for each growing season was equivalent to or greater than the external mineral N supply, which is composed of N deposition, chemical fertilizer application and GMm. However, there was a positive correlation between the N uptake in aboveground biomass and the total mineral N supply. It was assumed that 58% of the total mineral N supply was taken up by the grass. The N supply rates from soil and root-litter were estimated to be 331–384?kg?N?ha^?1?year^?1 and 94–165?kg?N?ha^?1?year^?1, respectively. These results indicated that the GMs and GMl also were significant inputs in the grassland N budget. The cumulative N₂O flux for each season showed a significant positive correlation with mineral N surplus, which was calculated as the difference between the total mineral N supply and N uptake in aboveground biomass. The emission factor of N₂O to mineral N surplus was estimated to be 1.2%. Furthermore, multiple regression analysis suggested that the N₂O emission factor increased with an increase in precipitation. Consequently, soil and root-litter as well as chemical fertilizer and manure were found to be major sources of mineral N supply in the grassland, and an optimum balance between mineral N supply and N uptake is required for reducing N₂O emission.     

Chemical characterization of conducive and suppressive soils for potato scab in Hokkaido,Japan

Potato common scab induced by Streptomyces scabies is a serious constraint for potato-producing farmers and the incidence of potato scab depends on the soil chemical properties. We examined the chemical characteristics of conducive and suppressive soils to potato common scab with reference to the chemical properties of nonallophanic Andosols, recently incorporated into the classification system of cultivated soils in Japan. Allophanic Andosols with a ratio of pyrophosphate-extractable aluminum (Al_p) to oxalate-extractable aluminum (Al_o) of less than 0.3–0.4 were “conducive” soils with a high allophane content of more than 3%. On the other hand, nonallophanic Andosols with a Al_p/Al_a ratio higher than this critical value were “suppressive” soils, and their allophane content was less than 2%. The concentration of water-soluble aluminum (AI) was also a useful index for separating conducive from suppressive soils as well as the Al_p/Al_a value and allophane content. The suppressive soils showed a much higher concentration of water-soluble Al at pH 4.5 to 5.5 than the conducive soils. The high concentration of water-soluble Al may be responsible for the control of the incidence of potato common scab in Andosols.     

Nitrogen flow on an organically managed beef farm in Hokkaido,Japan

Nutrient recycling should be effective at balancing nutrient flows in Japanese animal production. This means replacing imported feed with self-produced feed. The Yakumo Experimental Farm of Kitasato University has produced commercial beef under ‘organic’ management, without the use of agricultural chemicals or imported feed, since 2005. Using a data set obtained from 220 ha of grassland and 250 head of cattle over the 5 years from 2008 to 2012, we estimated nitrogen (N) flow. During 2011 and 2012, we measured grass production, cattle production (selling out), soil parameters and atmospheric deposition (from precipitation and atmospheric ammonia concentrations). To determine N fixation by clover (white clover, Trifolium repens L.), we compared grass + clover plots with grass-only plots. Averaged over the period, N components on the 220 ha of grassland comprised 1952 Mg soil N stock, 3.2 Mg N yr^?1 in living livestock, 14.3 Mg N yr^?1 uptake by grass growth (including 8.6 Mg yr^?1 of N fixed by clover), 15.7 Mg N yr^?1 applied in composted manure, 1.7 Mg N yr^?1 in imported bedding material, 2.8 Mg N yr^?1 in deposition and 1.41 Mg N yr^?1 in meat production. N in composted manure equaled about 0.8% of the huge soil N stock; N in grass production equaled about 0.7%, of which clover fixation supplied 60%; N deposition was not negligible; and N export by meat production was minor. These results show that on this organically managed farm, soil N stock increased gradually (by 8.6 Mg N yr^?1 [220 ha]^?1 = 39 kg N ha^?1 yr^?1 = 0.02% of the soil N stock) and N export was small. Our findings show that it is possible to balance N inputs with N outputs in a beef cattle enterprise without the need for feed or fertilizer imports.     

Influences of Forest Decline on Various Properties of Soils at Mt. Hirugatake, Tanzawa Mountains, Kanto District, Japan

At Mt. Hirugatake in the Tanzawa Mountains, Kanto district, Japan, the deciduous broadleaved forests have rapidly declined. In our previous studies, we reported that the amount of soil organic matter had significantly decreased at the early and final stages of forest decline, and that the soil microbial biomass also showed a large decrease at these stages, suggesting that the composition of soil organic matter might have also changed with forest decline. To clarify the influences of forest decline on the composition of soil organic matter, the amount of humic substances, optical properties of humic acid, and the amount of soil carbohydrates in surface soils at different stages of forest decline were investigated. The amounts of humic acid and fulvic acid decreased to a lesser extent at the early and middle stages of forest decline, and showed a significant decrease at the final stage. As the amount of humin significantly decreased at the early stage, it was plausible that the distinct decrease in the total carbon content of the soil surface horizons at the early stage of forest decline was induced by the decrease in the amount of humin, and at the final stage, by the decrease in the amounts of humic acid and fulvic acid. The amount of soil carbohydrates did not change appreciably with forest decline although the soil organic matter content markedly decreased. It was suggested that most of the carbohydrates in the soil surface horizons were in a stabilized form consisting of complexes with humic substances, metals, and minerals, and would not be affected by the environmental changes associated with forest decline.     

Oxygen Isotopic and Chemical Characterization of Soils with Surface Gleyzation from Central and Northeastern Japan

Four soils with surface gleyzation (Humi-stagnic Gleysols; provisional) from central and northeastern Japan are characterized by a combination of oxygen isotopic, chemical dissolution (pyrophosphate and acid oxalate) and X-ray diffraction analyses. Oxygen isotopic composition of quartz indicates residuum of volcanic materials and eolian dust from interior China as major parent materials of the clayey surficial horizons.     

Soil respiration and methane flux in adjacent forest,grassland, and cornfield soils in Hokkaido,Japan

Soil respiration and methane flux from adjacent forest, grassland, and cornfield were measured by using the closed chamber method from June to November, 1999 in Shizunai, Hokkaido, Japan, where the soil was an Aquic Humic Udivitrands derived from volcanic ash. The forest soil absorbed methane, at arate ranging from -0.12 to -0.02 mg C m_-2 h_-1, while the grassland soil emitted methane, at a rate ranging from undetectable levels to 0.18 mg C m_-2 h_-1. In the cornfield soil methane flux ranged from -0.01 to 0.04 mg C m_-2 h_-1. The soil respiration rate varied from 3 to 230 mg C m_-2 h_-1, 27 to 372 mg C m_-2 h_-1, and 29 to 156 mg C m_-2 h_-1 for the cornfield, grassland, and forest soils, respectively. Linear regression analysis demonstrated that the methane flux rate was positively correlated with the soil water-filled pore space (WFPS), and negatively correlated with the relative gas diffusion coefficient (D/D _o) and air-filled pore space (AFPS). Soil respiration rates were positively correlated with the soil temperature at all the sites. The Q ₁₀ value was 4.8, 3.3, and 1.9 for the cornfield, grassland, and forest soils, respectively.     

Spatial Distribution of the Components of Carbon Cycle in Soils of Forest Ecosystems of the Northern,Middle, and Southern Taiga of Western Siberia

Eurasian Soil Science - In the course of studies in typical forest ecosystems of the northern, middle, and southern taiga of Western Siberia performed at the peak of the growing season, the spatial...     

土壤溶质随径流迁移基本特征分析

土壤溶质随地表径流迁移是一个复杂的过程,受到多种因素的影响。在总结国内外相关研究成果的基础上,分析了土壤溶质随地表径流迁移的主要物理过程,以及各个物理过程的具体特征。同时分析了影响土壤溶质随地表径流迁移的主要因素的影响程度和特点,为建立描述土壤溶质随地表径流迁移过程的数学模型,以及发展控制措施提供参考。     

水解聚马来酸酐对森林暗棕壤和草地退化盐碱地土壤 胶体表面结构与组成的影响

水解聚马来酸酐(HPMA)能起到土壤改良的作用,进而促进种子萌发及植物生长,但是其与土壤相互作用的深层机理尚未阐明。基于此本文选用HPMA处理森林暗棕壤和草地退化盐碱地土壤胶体,并用激光粒径仪、原子力显微镜、扫描电镜、X射线衍射、红外光谱、X射线光电子能谱进行分析,探究HPMA对土壤胶体表面结构特征、矿物组成和有机组成的影响,旨在揭示HPMA对不同土壤胶体的影响差异的深层机理。结果显示,HPMA能够改良退化土壤的原因应该与其对土壤胶体表面结构特征、矿物结晶和有机化学元素组分的影响有关,但对森林暗棕壤和草地退化盐碱地土壤的影响存在明显差异。对于森林暗棕壤这种优质土壤,HPMA处理后,矿物质的结晶度有降低的趋势,但并没有产生强烈的化学反应,多数官能团趋向于增加,碳酸盐官能团降低幅度不是很大,约3%~8%,土壤胶体粒径增加了,其中表层增加了13.62%,深层增加了34.96%,但只有深层土壤达到显著水平。而对于草地退化盐碱地土壤,土壤胶体粒径显著增加(27.54%),达到了统计学显著水平(P0.05),除了石英相对结晶度降低了7.10%,其余都降低了30%以上,导致不同土壤矿物的晶粒尺寸显著增加了(水云母、蛭石、高岭石的晶粒尺寸分别增加101.37%、56.16%、50.76%),多数官能团的相对含量降低,其中碳酸盐官能团降低量最大,达到96.79%,这些使得土壤元素配比逐渐趋向于优质土壤(C:O=0.27;C:N=9.98;C:Si=0.91;O:Si=3.38;Si:N=10.93),这可能意味着HPMA与土壤胶体中的碳酸钙等不同土壤矿物发生了强烈的化学反应,从而影响了土壤晶粒结构和化学组成,进而起到土壤改良的作用。