19 research outputs found
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Spatially explicit inter-temporal forest management decision under the risk of fire
This paper presents a framework for analyzing efficient spatial allocation of forest
management efforts - fuel treatment and harvest - under the risk of fire. The framework
integrates a fire behavior model and a spatially-explicit stochastic dynamic optimization
model. I investigate the effects of spatial interaction across plots during forest fires - in
particular a spatial externality - on efficient allocation of fuel management efforts. This spatial externality is captured in a spatial endogenous risk framework - decisions affect
a risk distribution over space. By solving computationally for a number of initial bioeconomically
heterogeneous landscapes, general insight into implementing spatial allocation
of fuel management efforts is derived. Sensitivity analyses are conducted to evaluate
various economic and physical environments and their impact on the optimal solutions.
Because the optimal spatial allocation of fuel management efforts depends on a spatial
distribution of "value" and "risk", the decision generated from a conventional dynamic
stand level (or aspatial forest level) model or a simple dynamic spatial model can be suboptimal.
Numerical solutions demonstrate that the risk of value loss by fire damage does
not necessarily shorten the optimal rotation age because of spatial externalities. These
analyses also show that a land manager faces spatially explicit trade-offs in deciding how
to investment in fuel treatments
Spatial Endogenous Fire Risk and Efficient Fuel Management and Timber Harvest
This paper integrates a spatial fire behavior model and a stochastic dynamic optimization model to determine the optimal spatial pattern of fuel management and timber harvest. Each years fire season causes the loss of forest values and lives in the western US. This paper uses a multi-plot analysis and incorporates uncertainty about fire ignition locations and weather conditions to inform policy by examining the role of spatial endogenous risk - where management actions on one stand affect fire risk in that and adjacent stands. The results support two current strategies, but question two other strategies, for managing forests with fire risk.Resource /Energy Economics and Policy,
Research and Development of Imaging Bolometers
An overview of the research and development of imaging bolometers giving a perspective on the applicability of this diagnostic to a fusion reactor is presented. Traditionally the total power lost from a high temperature, magnetically confined plasma through radiation and neutral particles has been measured using one dimensional arrays of resistive bolometers. The large number of signal wires associated with these resistive bolometers poses hazards not only at the vacuum interface, but also in the loss of electrical contacts that has been observed in the presence of fusion reactor levels of neutron flux. Imaging bolometers, on the other hand, use the infrared radiation from the absorbing metal foil to transfer the signal through the vacuum interface and out from behind a neutron shield. Recently a prototype imaging bolometer known as the InfraRed imaging Video Bolometer has been deployed on the JT-60U tokamak which demonstrates the ability of this diagnostic to operate in a reactor environment. The application of computed tomography demonstrates the ability of one imaging bolometer with a semi-tangential view to produce images of the plasma emissivity. In addition, new detector foil development promises to strengthen the foil and increase the sensitivity by an order of magnitude
How well are biodiversity drivers reflected in protected areas? A representativeness assessment of the geohistorical gradients that shaped endemic flora in Japan
Residents' Preference and Willingness to Pay for Conservation of Homestead Woodlands-a case of coastal villages in Okinawa Prefecture, Japan
Fukugi(Garcinia subelliptica Merr.) tree homestead woodland has prevailed widely along the Ryukyu Islands, the southernmost part of Japan. The homestead woodland has played a key role in protecting the settlements from strong winds, as well as providing timber and green manure and etc. in the past. However, with the rapid urbanization and economic and societal change, homestead woodlands greatly vanish in Japan. The ecological multi functions of forests have been stressed in recent researches. The management and conservation of homestead woodland is little studied, although they have been closely relevant to habitants' wellbeing. The primary purpose of this study is to reveal dwellers' perception of homestead woodlands. The secondary purpose is to explore dwellers' willingness to conserve homestead woodlands by using the contingent valuation method (CVM). Survey was conducted in three hamlets with the best preserved Fukugi homestead woodlands in Okinawa Prefecture. Overwhelming majority of the respondents, accounting for around 91%, preferred homestead woodlands to being conserved. Residents have highly valued the amelioration of micro-climate by homestead woodlands, such as windbreak and cooling the air in summer. In contrast, the contribution to biodiversity was slightly assessed, in particularly, in two small isolated islands. It was revealed that residents at small isolated have highly valued standing Fukugi trees concerning the function of preventing from typhoons. It was found that Fukugi homestead woodlands were considered as private goods by the dwellers as well as local authority. About half of the respondents perceived that the house owners and/or local authority such as hamlet community should be responsible for the conservation. The interesting finding in this study revealed that the residents' attitude toward homestead woodland was significant factor influencing their willingness to pay for woods preservation. Around 25% of the total respondents rejected the payment. Estimated mean and median WTP values were JPY 1,451/household and JPY 1,000/household, respectively. Thus, environmental education and awareness arising will contribute to better conservation of their homestead woodlands. It is urgent to evaluate the non-use value of homestead woodlands as environmental goods and urge local policy makers to include Fukugi homestead woodlands in landscape planning and conservation.本部町の備瀬・今帰仁村今泊・渡名喜島などに現存するフクギ屋敷林は、その推定樹齢から、その多くが18世紀の30年代以降に、王府によって計画的に造成されたものであることが、これまでの調査研究でわかってきた。フクギ林が選抜された最大の理由は、フクギのもつ多機能性(たとえば、潮害や台風からの防備、津波などからの防災、防火樹、建築材、染料など)に起因している。しかし、これらのフクギ林は、沖縄戦と終戦直後の木材不足による乱伐や開発によってそのほとんどが消滅した。現在では、一部の地域でその面影をみるのみである。フクギ屋敷林をどう保全し、今後、どのように活用すべきか、その方策に関する研究はほとんど見られない。本報告の目的は以下の2つである。第1は、フクギ屋敷林について、地域の住民がどのような意識をもっているか、アンケート調査から、この点を明らかにすることである。第2は、CVMの手法を用いて、フクギ屋敷林の多面的な価値の評価を行い、それによって住民や行政による保全対策の在り方を考察することである。CVMとは、一般の市民に対してアンケートを行い、仮想的な条件を想定し、環境保全や改善のために支払ってもよいと考える最大金額、すなわち支払意志額(Willingness to Pay; WTP)等を質問し、環境価値を評価する手法である。沖縄県でフクギの屋敷林が最も多く残されている3つの地域(沖縄本島北部の備瀬、粟国島、渡名喜島)でアンケート調査を行った。アンケート調査の結果、圧倒的多数の人が(91%)、フクギの屋敷林の存在意義を認めている。また、多くの住民の回答者や行政の回答から、フクギ屋敷林は住民の私的財産に属すると考えてもいることが分かった。回答者の約半数が、屋敷の所有者またはその村落共同体、地方自治体がフクギ屋敷林の保全に責任を負わなければならない、と答えている。屋敷林管理の放棄(たとえば空屋敷など)は、コミュニティ全体の集落景観や緑の空間によってもたらされる快適性の恩恵を大幅に低下させてしまうのではないかとの懸念もみられる。フクギ屋敷林を守っていくために「フクギ屋敷林保全基金」といったものを設立すると仮定し、回答者にフクギ屋敷林の保全基金にどの程度の支払い意志(WTP)があるのかを調査した。それによると支払い意志額(WTP)の1世帯当たりの平均値は,1,451円となった。なお,中位値を計算すると1,000円となった。支払い意志額の分析から,住民たちは全体としてフクギ屋敷林を評価していることが分かった。推計結果を見ると、「安定した収入源がある」と回答した者は,より大きなWTPを示していることが確認できた。また、「フクギ屋敷林を活用すべき」と回答した人のWTPも比較的高い数値を示した。以上のことから、フクギ屋敷林の保全に関しては、その評価に対する潜在的な意識は高く、新たな活用法を開発し、地域住民自ら保全活用する施策を見出して、それを行政側が支援して行く体制の構築が、今求められている
Residents' Preference and Willingness to Pay for Conservation of Homestead Woodlands-a case of coastal villages in Okinawa Prefecture, Japan
Spatial Endogenous Fire Risk and Efficient Fuel Management and Timber Harvest
This paper integrates a spatial fire behavior model and a stochastic dynamic optimization model to determine the optimal spatial pattern of fuel management and timber harvest. Each year's fire season causes the loss of forest values and lives in the western US. This paper uses a multi-plot analysis and incorporates uncertainty about fire ignition locations and weather conditions to inform policy by examining the role of spatial endogenous risk - where management actions on one stand affect fire risk in that and adjacent stands. The results support two current strategies, but question two other strategies, for managing forests with fire risk
Spatial-Endogenous Fire Risk and Efficient Fuel Management and Timber Harvest
This paper integrates a spatial fire-behavior model and a stochastic dynamic-optimization model to determine the optimal spatial pattern of fuel management and timber harvest. Each year’s fire season causes the loss of forest values and lives in the western United States. We use a multi-plot analysis and incorporate uncertainty about fire ignition location s and weather conditions to inform policy by examining the role of spatial endogenous risk—where management actions on one stand affect fire risk in that and adjacent stands. The results support two current strategies, but question two other strategies, for managing forests with fire risk.