Influence of clear-cutting on the chemistry of runoffs in a mixed forest watershed under heavy snowfall, Hokkaido, Japan

The global environmental change caused by human activity is supposed to alter the life and the situation of those living in northern region drastically. A couple of subjects are lying to protect our surroundings in the North, the thinning of sea ice due to global warming, the land use change through the development of tourism, the destruction of forest caused by acid deposition and/or commercial logging operation. Hokkaido and Finland have several similarities about natural conditions (cold and snowy climate, abundant boreal forest, the presence of sea ice, deer and reindeer etc.), though Hokkaido locates relatively lower latitude compared with Finland. From this point of view, it is natural that the researchers of both sides join together and discuss those facing environmental problems. The Hokkaido University Forests has the vast area of forests (ca. 70,000ha) in Hokkaido, which ranged from boreal forest to warm temperate forests, and is the largest experimental station in Japanese university system. Many environmental and ecological studies have been conducted in the University Forests. In addition, long term monitoring researches have been launched during last two decades in our forests and produced lots of useful data for global environmental and ecological monitoring system. In this context, the Hokkaido University Forests can contribute the collaborative research and projects through the environmental and ecological fields concerning to boreal forests. Especially, what we consider as an adequate cooperation is about the impact of human activities such as global warming, acid deposition, forest fire, logging operation and so on. Long term monitoring sites are set up to estimate the forest disturbance caused by human impacts in the University Forests. As an example of possible collaborative research, I will focus on the long term field experiment about the influence of logging operation, which includes timber harvesting and the scarification of ground surface, on the elution process of the forest watersheds. To demonstrate the relationship between the forest disturbance and the response of watersheds, a large spatial scale of practical research is introduced in the watersheds. Commercial logging and its influence on the surrounding environment is one of the common subject to Japan and Finland. In order to discuss this subject, it is necessary that the forest vegetation and environmental condition are similar as much as possible between the targeted areas. In this meaning, only Hokkaido can make a comparative research with Finland about this subject in Japan.Session 2.1: Biodiversity and Environmental Protection in the Nort

An Atlas of Collembola Species in the Sapporo Experimental Forest of Hokkaido University in Northern Japan

Collembola (Hexapoda: Collembola) is one of the most common soil animals in forests. Collembolans play an essential role in soil ecosystems, but their community structure and ecological role in forests are not fully understood because of difficulties with their classification. We have consequently developed an atlas of Collembolans in certain forest stands within the Sapporo Experimental Forest. The community structure of Collembolans varied greatly in each forest stand. The Isotomidae family was predominant in a mature larch stand and in young broad-leaved mixed stands, but in a spruce plantation the dominant family was Onychiuridae. The most abundant genera in the Isotomidae family also varied with the type of forest stand: Folsomia was found in larch and spruce stands, and Desoria and Pteronychella in young broad-leaved mixed stands. We observed 13 species of Collembola in our study sites

Wild plant species as subjects in O₃ research

Tropospheric ozone (O3) occurs in high concentrations nowadays and affects a many plant species in Northern hemisphere. Numerous wild plant species are known to be negatively affected by O3, and this may impact biodiversity and ecosystems in near future. Given the importance of O3 research with wild plants, we provide a list of 473 relevant taxa - that have been used as a subject of O3 research - as a research material, under various controlled-environment facilities, along with information about their response to O3. In addition, we include species which have been reported that they had developed ozone-like (but not confirmed) symptoms. This list of taxa along with the references is considered an important database, useful to researchers when planning their relevant investigations

Development of teaching materials for international course students on the ancient forest culture of the Hokkaido University Campus

Many plant remains including pollen fossils, wooden artifacts and charred woods from Epi-Jomon culture (about 2000 years ago) to the Ainu culture period (about 400 years ago) have been excavated from the Hokkaido University Campus sites. Wood identification and pollen analysis have revealed the forest vegetation and wood utilization by ancient people, i.e., the ancient forest culture, for each era in this site. It is necessary to organize systematically the data concerning this ancient forest culture for showing an importance role of our campus as state property. Furthermore, the elucidation of the ancient forest culture is important because it can lead to an understanding of how ancient peoples managed forests and we may learn forest management techniques suitable for changing environment. Hokkaido University Forests has developed a course on "Environmental Science for Biological Resources" as a part of "Hokkaido University Short Term Exchange Program", in short, HUSTEP. Therefore, we summarized a part of this ancient forest culture of Hokkaido University campus sites concisely and tried to develop teaching materials by creating display panels about this to introduce these to student from overseas, in particular the HUSTEP students

Relationship between the riverine nitrate-nitrogen concentration and the land use in the Teshio River watershed, North Japan

The present research investigated the relationship between nitrate-nitrogen (NO3-N) in river water and the land use/land cover (hereafter, land use) in the Teshio River watershed located in northern Hokkaido island to understand the effect of human activities such as agriculture, forestry, industry, and urbanization in the drainage basin on the river ecosystem quality and services. River water was sampled at nine points seasonally during a two-year period and the nutrients concentration was measured. Land use profiles were estimated at two spatial scales-riparian and sub-catchment for each sampling station. The spatial pattern of water quality in the Teshio River showed increased NO3-N levels associated with agriculture and urban expansion, and forest reduction in the watershed. Land use at the riparian scale closely reflected that at the sub-catchment scale, which masked the unique riparian buffer effect on the river water condition. The high agricultural and reduced forest area in the riparian zone, especially in the upper middle reach, could be a possible reason for a decline of ecosystem service for the provisioning of clean water and habitat for aquatic organisms. Measures towards sustainable and more nature-friendly agricultural management are necessary in the area to protect the Teshio River ecosystem and its ecosystem services

Impact of elevated CO2 on root traits of a sapling community of three birches and an oak : a free-air-CO2 enrichment (FACE) in northern Japan

We evaluated the root response to elevated CO2 fumigation of 3 birches (Betula sp.) and 1 deciduous oak (Quercus sp.) grown in immature volcanic ash soil (VA) or brown forest soil (BF). VA is a nutrient-poor, phosphorus-impoverished soil, broadly distributed in northern Japan. Each species had been exposed to either ambient (375-395 mu mol mol(-1)) (aCO(2)) or elevated (500 mu mol mol(-1)) (eCO(2)) CO2 during the daytime (more than 70 mu mol m(-2) s(-1)) over 4 growing seasons. The results suggest that eCO(2) did not cause an increase in total root production when the community had grown in fertile BF soil, however, it did cause a large increase when the community was grown in infertile VA soil. Yet, carbon allocation to plant roots was not affected by eCO(2) in either the BF or VA soils. Rhizo-morphogenesis appeared to occur to a greater extent under eCO(2). It seems that the saplings developed a massive amount of fine roots under the VA and eCO(2) conditions. Unexpectedly, eCO(2) resulted in a larger total root mass when the community was grown in VA soil than when grown in BF soil (eCO(2) x VA vs. eCO(2) x BF). These results may hint to a site-specific potential of communities to sequester future atmospheric carbon. The growing substance of plants is an important factor which root response to eCO(2) depends on, however, further studies are needed for a better understanding

Roles of dominant understorySasabamboo in carbon and nitrogen dynamics following canopy tree removal in a cool-temperate forest in northern Japan

To clarify the role of dense understory vegetation in the stand structure, and in carbon (C) and nitrogen (N) dynamics of forest ecosystems with various conditions of overstory trees, we: (i) quantified the above- and below-ground biomasses of understory dwarf bamboo (Sasa senanensis) at the old canopy-gap area and the closed-canopy area and compared the stand-level biomasses of S. senanensis with that of overstory trees; (ii) determined the N leaching, soil respiration rates, fine-root dynamics, plant area index (PAI) of S. senanensis, and soil temperature and moisture at the tree-cut patches (cut) and the intact closed-canopy patches (control). The biomass of S. senanensis in the canopy-gap area was twice that at the closed-canopy area. It equated to 12% of total biomass above ground but 41% below ground in the stand. The concentrations of NO3− and NH4+ in the soil solution and soil respiration rates did not significantly change between cut and control plots, indicating that gap creation did not affect the C or N dynamics in the soil. Root-length density and PAI of S. senanensis were significantly greater at the cut plots, suggesting the promotion of S. senanensis growth following tree cutting. The levels of soil temperature and soil moisture were not changed following tree cutting. These results show that S. senanensis is a key component species in this cool-temperate forest ecosystem and plays significant roles in mitigating the loss of N and C from the soil following tree cutting by increasing its leaf and root biomass and stabilizing the soil environment