2月の公開セミナー

Shifting crop calendar is considered to be one of the effective adaptation measures to avoid impact of high temperature on crop yield and quality under the conditions of anticipated temperature increase in the future. Using multiple climate change scenarios derived from CMIP5, changes in rice yield and quality were simulated by the process-based rice simulation model. In the seminar, I will present the regional characteristics in effectiveness of shifting transplanting date as adaptation for rice cultivation in Japan.

Quantifying the ecosystem carbon balance at decadal scales is important for evaluating the reliability of annual values and understanding its trend.

We started the continuous measurements of the major components of the ecosystem carbon budget at the Mase site in 1999 and have recently summarized the data collected after 2002.

I briefly introduce the results, the carbon balance and its inter-annual variability, and the future direction in the seminar.

In a study on apple growers in Nagano, Japan, Fujisawa & Kobayashi (2011) identified two types of farmers, of which the farmers ship their product mostly to the mass market (M-type). The other type of farmers sell their product directly to the consumers (D-type). In response to the rising air temperature and delaying maturity, the M-type farmers took means to accelerate the coloring of fruits, whereas the D-type of farmers did not take such means but just delayed the harvest. The sales channel has thus been identified as a major determinant of the farmers’ responses to the climate change.

The case studies on Japanese apple growers along with a study on apple growers in South Africa were synthesized by Fujisawa et al. (2015), who found that D-type farmers tend to make bottom-up adaptations that are autonomous and often proactive, whereas the M-type farmers, including those in South Africa, tend to accept top-down adaptations that are reactive and often remedial to ongoing climate change impacts.

According to the model of diffusion of innovations (Rogers, 2003), the M-type farmers’ adaptation can be viewed as a centralized top-down system, where the technical fixes to the emerging problems are designed by experts and adopted by farmers. The adaptation by D-type farmers would, by comparison, be viewed as the decentralized system, where the innovation bubbles up from the farmers and diffuses among their peers. Moreover, the case of Kazuno indicates the possibility of timely combination of the two systems.

Why, then, the sales channel matters in the farmers’ adaptation?

References
Fujisawa M, Kobayashi K (2011). Climate change adaptation practices of apple growers in Nagano, Japan. Mitigation and Adaptation of Strategies for Global Change 16, 865-877. doi: 10.1007/s11027-011-9299-5. Fujisawa M, Kobayashi K (2013). Shifting from apple to peach farming in Kazuno, Northern Japan: Perceptions of and responses to climatic and non-climatic impacts. Regional Environmental Change 13, 1211-1222. DOI.10.1007/s10113-013-0434-6.
Fujisawa M, Kobayashi K, Johnston P, New M (2015). What drives farmers to make top-down or bottom-up adaptation to climate change and fluctuations? A comparative study on 3 cases of apple farming in Japan and South Africa. PLoS ONE 10(3): e0120563. doi:10.1371/journal.pone.0120563.
Rogers EM (2003). Diffusion of Innovations. Fifth edition. Free Press, New York.

植生遷移メカニズムの解明は、生態学の中心的な研究課題のひとつであり、植生動態の将来予測や生態系管理への応用上も重要である。本セミナーでは、大規模な人為撹乱である泥炭採掘後の湿原において、地上部植生およびシードバンクの構造が時間とともに変化するメカニズムを追った研究をいくつか示し、植生再生管理への応用例を紹介したい。また、人為撹乱が湿原への外来植物の侵入を促進する可能性についても少し述べたい。

わが国では、これまで農地と林野で異なる調査分類法により土壌図が作成され、それらを継ぎ当てて全国土の土壌図として用いてきた。そのため、 わが国の土壌の種類ごとの分布面積や土壌炭素賦存量などの土壌資源インベントリーを包括的に評価することは困難な状況であった。そこで本研究 では、土地利用に左右されず土壌分類可能な包括的土壌分類を用いて、既存の文献データおよび現地土壌調査の結果などを統一的にデータベース化 して、新たな日本土壌図を作成した。

農環研でやってきた土壌分類関係の研究の流れを概観する予定

カメムシ目のマダラナガカメムシ科およびカスミカメムシ科について分類学的研究を行ってきたところ、近年日本および東南アジアから何種かの未記載種を発見し、これらを新種として記載した。具体的には日本産のヒメナガカメムシ属分類学的再検討を行い1新種を含む5種の確認をした。また、マレーシア及びインドネシアから記載したヒョウタンカスミカメムシ属についても紹介する。

Climate change impacts on regional-scale cryosphere in snowy areas of Japan have been actualized on local industries, and will affect cropping system and agricultural water resources. The speaker has taken part in on-site observations of snow depth and winter weather in Sugadaira, Nagano Pref., and surrounding snowy area for around 20 years. Previous own works and related studies are reviewed and ongoing & future research strategy are discussed.

Open-field experiment of environmental manipulation like FACE provide us opportunities to observe the real responses of plants and ecosystem under the projected future climate. In FACE experiment, the increase of the atmospheric CO₂ directly affects the plant growth, physiology and productivity, but also indirectly affects them via the change of the canopy micrometeorology due to stomatal closure by the elevated CO₂, which are the response in the real world. While, ecosystem warming experiments elevate the temperatures of the target, but their micrometeorological structure can be different from the real world because warming manipulation itself has to alter the heat balance. In 2015 summer, we conducted T-FACE (Temperature Free-Air Controlled Enhancement) experiment at rice paddy in Tsukubamirai FACE. We attempted to quantify the micrometeorological change due to FACE and T-FACE by measurement and model analysis. The preliminary results will be shown to elucidate the relation between the rice response and micrometeorological factors.