Faculty Profiles - IWANAGA Seiji

Report on the 133nd Annual JFS Meeting Workshop “Gather! Forest of Conference”

A study of trail maintenance utilizing volunteers in Chubusangaku National Park

Hori Akiho, Iwanaga Seiji, Harada Kazuhiro

The Japanese Forest Society Congress Vol. 134 ( 0 ) page： 87 2023.5

Trends of private forest ownership and the role of forest owners’ associations in Norway

Iwanaga Seiji, Sato Noriko, Koga Shiori

page： 46 - 53 2023.5

Language：English Publishing type：Research paper (scientific journal)

This study gives insight into the trends of individual private forest ownership and forest management in Norway. Contrary to Japanese forest management, larger forest areas are actively managed by private owners and forest owners’ association (FA) are more active in Norway. The questionnaire survey using Google Form was conducted for members of two of the four FAs in Norway. One of the FAs is Glommen Mjøsen Skog (64 respondents with an average forest area of 453 ha). The members of Glommen Mjøsen Skog own larger properties suitable for forestry. The other is Allskog (41 respondents with an average forest area of 198 ha). Allskog’s members are located on the west coast of Norway where forestry is more difficult due to many steep slopes and the smaller properties. Both FAs’ members were interested in expanding their properties for the purpose of “expanding forestry management” and “asset formation”. In Allskog, 10 of the respondents (24%) purchased 114 ha on average in the past five years. On the other hand, 15 of the respondents in Glommen Mjøsen Skog answered that they expanded their property with 187 ha on average. More than 50% of the respondents in Glommen Mjøsen Skog have successors, while 40% in Allskog. The results indicate that there is a difference in the attractiveness of forest ownership and forestry. Regarding the operation of forest management, 47% and 59% answered “done by respondents themselves or their family members” in Glommen Mjøsen Skog and in Allskog, respectively. Similarly, 19% and 41% answered that harvesting was implemented by “respondents themselves or their family members” in Glommen Mjøsen Skog and in Allskog, respectively. Because members in Allskog own smaller properties, it seems that forest owners have a tendency to carry out all operations by themselves or their family members.

CiNii Research

ノルウェーの森と

岩永青史

農中総研調査と情報 Vol. 2023.01 ( 94 ) page： 22 - 23 2023.1

Takada Noriyo, Iwanaga Seiji, Kimura Megumi, Yamagawa Hiromi, Nanko Kazuki, Takeuchi Hiroe, Takayama Norimasa

Journal of the Japanese Forest Society Vol. 105 ( 5 ) page： 187 - 190 2023

Statistical analysis regarding contribution of local timber to timber self-sufficiency rate rising Reviewed

IWANAGA Seiji

Vol. 70 page： 47 - 50 2022.6

Determinants and Challenges of Community Sand Forest Management in Vietnam Reviewed International coauthorship International journal

Hoang Huy Tuan, Nguyen Van Minh, Nguyen Thi Hong Mai, Tran Thi Thuy Hang, Seiji Iwanaga

Forests Vol. 13 ( 4 ) page： 561 - 561 2022.4

Determinants and Challenges of Community Sand Forest Management in Vietnam Reviewed International coauthorship

Hoang Huy Tuan, Nguyen Van Minh, Nguyen Thi Hong Mai, Tran Thi Thuy Hang, Seiji Iwanaga

forests Vol. 13 page： 561 2022.3

Domestic large-diameter log use in the Japanese lumber manufacturing industry: focusing on regional differences Reviewed International journal

Seiji Iwanaga, Masato Hayafune, Wataru Tanaka, Yuji Ikami

Journal of Forest Research Vol. 27 ( 1 ) page： 8 - 14 2022.1

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Informa UK Limited

Japan's postwar policies with respect to forestry management have led to the aging of planted forests and a shift toward large-diameter logs that has created a challenge for how to use such logs in the lumber manufacturing industry. In recent years, medium-diameter logs have been the predominant type, and there has been less demand for large-diameter logs. This study examines the Japanese lumber manufacturing industry's consumption of domestic timber using survey data from 21 member companies of the Domestic Timber Sawmill Association. The results suggest that regional characteristics and the tree species consumed are the two main factors that drive the decision to use large-diameter logs. While current demand for large-diameter logs is considered low, the results show that demand is present, and there are signs of growing consumption of these logs within the lumber manufacturing industry. As the current machinery that handles medium-diameter logs depreciates, it is expected that companies will respond by either introducing machinery that can accommodate large-diameter logs or changing their products.

DOI： 10.1080/13416979.2021.1998949

再利用木材の流通と市場における課題に関する研究

佐野百香, 岩永青史

木材利用システム研究 Vol. 8 ( 0 ) page： 9 - 12 2022

Participation of Local People in the Payment for Forest Environmental Services Program: A Case Study in Central Vietnam Invited Reviewed International coauthorship International journal

Hoang Phan Bich Ngoc, Takahiro Fujiwara, Seiji Iwanaga, Noriko Sato

Sustainability Vol. 13 ( 22 ) page： 12731 - 12731 2021.11

Actual situations and challenges of timber legality assurance system in Indonesia

Kitayama Shun, Iwanaga Seiji, Harada Kazuhiro

Japanese Journal of International Forest and Forestry Vol. 111 ( 0 ) page： 3 2021.8

Challenges of the Payment for Forest Environmental Services (PFES) program in forest conservation: a case study in Central Vietnam Reviewed International coauthorship International journal

Hoang Phan Bich Ngoc, Takahiro Fujiwara, Seiji Iwanaga, Noriko Sato

Journal of Forest Research Vol. 26 ( 6 ) page： 1 - 10 2021.8

Changes in the Vietnamese Timber Processing Industry: A Case of Quang Tri Province, North Central Region Reviewed International coauthorship International journal

Seiji Iwanaga, Dang Thai Hoang, Hirofumi Kuboyama, Dang Thai Duong, Hoang Huy Tuan, Nguyen Van Minh

Forests Vol. 12 ( 8 ) page： 984 - 984 2021.8

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：MDPI AG

Vietnam’s forestry policies have expanded the area of planted forests in order to meet the supply of raw materials for the timber processing industry. However, the diversity and volume of demand in the industry have also increased, and a shortage of raw materials can be assumed. For clarifying the correspondence of stakeholders, we explore changes in the resource supply behavior of forestry companies and procurement strategies of companies that manufacture lumber for glued laminated timber, medium density fiberboard (MDF) and wood pellets. Next, we discuss issues and future developments surrounding the supply and demand for timber from planted forests. According to a survey of Quang Tri Province, both industrial and on-farm tree planting play an important role in Vietnam’s wood industry. The origin of the supply has been categorized according to its purpose (products). On the other hand, with the declining supply of imported timber and natural forest timber, inquiries from sawmills and glued laminated timber factories for timber from planted forests have increased, and wood pellet manufacturers are facing competition for raw material procurement with MDF manufacturers, and the supply of timber from planted forests is becoming scarce. The key to the solution lies in improving the low productivity of current on-farm tree planting. To this end, forming farmer groups upon the acquisition of forest certification will help achieve economies of scale and bargaining power.

DOI： 10.3390/f12080984

3. Vietnamese Forest Resource Strategies: Shift in Raw Materials to Plantation Forest Timber (The 2020 Spring Symposium held by the Japanese Forest Economic Society “Southeast Asian Forestry in the Post-natural Forest Era”)

IWANAGA Seiji

FOREST ECONOMY Vol. 74 ( 5 ) page： 15 - 15 2021

製材業における国産大径材利用の実態と課題 Reviewed

岩永青史, 早舩真智, 田中亘, 伊神裕司

中部森林研究 Vol. 68 page： 57 - 58 2020.6

Impact of policies on raw material procurement in the Vietnamese timber processing industry: a case study of sawmills in Hue City Reviewed International coauthorship International journal

Seiji Iwanaga, Dang Thai Duong, Ngyen Van Minh

Journal of Forest Research Vol. 25 ( 2 ) page： 59 - 68 2020.3

Vietnamese Forest Resource Strategies: Shift in Raw Materials to Plantation Forest Timber Invited Reviewed

Seiji IWANAGA

Journal of Forest Economics Vol. 66 ( 1 ) page： 35 - 44 2020.3

Policy effects for forest conservation and local livelihood improvements in Vietnam: a case study on Bach Ma National Park Reviewed International coauthorship International journal

Seiji Iwanaga, Shigeki Yokoyama, Dang Thai Duong, Nguyen Van Minh

Journal of Forest Research Vol. 24 ( 5 ) page： 267 - 274 2019.8

東南アジアにおける木質面材の生産、消費、輸出入の動向

岩永青史, 早舩真智

木材情報 Vol. 339 page： 10-13 2019.8

南洋材丸太および合板をめぐる近年の動向と日本の合板産業

岩永青史, 早舩真智

木材情報 Vol. 338 page： 16-19 2019.7

The tendency of expanding forest certification in Vietnam: Case analysis of certification holders in Quang Tri Province Reviewed International coauthorship

Iwanaga S, Duong DT, Ha TH, Minh NV

JARQ Vol. 53 ( 1 ) page： 67 - 78 2019

Impact of the change in raw material supply on enterprise strategies of the Japanese plywood industry Reviewed International journal

Iwanaga S, Tsuzuki N, Kuboyama H

Journal of Forest Research Vol. 23 ( 6 ) page： 1 - 11 2018

米国における建築用面材利用の歴史的展開から見る日本の合板産業

岩永青史, 久保山裕史, 都築伸行

木材情報 Vol. 326 page： 19-22 2018

Diverse aspects of the forestry management reorganization － Suggestion for forestry business －

OTSUKA Ikumi, HORI Yasuto, YAMADA Shigeki, IWANAGA Seiji, AMANO Tomomasa, KOMAKI Takaaki, MOCHIDA Haruyuki

Bulletin of the Forestry and Forest Products Research Institute Vol. 17 ( 3 ) page： 233 - 248 2018

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：国立研究開発法人森林研究・整備機構森林総合研究所

Downturns in Japanese timber prices are currently discouraging the participation of Japan's forest owners inmanagement practices, to the extent that timberlands are being sold and reforestation and renewal projects are being abandoned. In contrast, some corporate entities that actively require a timber supply are engaging in, and evenexpanding, forest management investment; long-term forest management are also being established. Thus, Japan'sapproach to forest management is undergoing reorganization.In 2008, we had an opportunity to discuss with two major financial institutions about the possibility of the foresttrust in Japan. This study aims to clarify the factors regarding main difficulties of the forestry business through theforest trust indicated by major financial institutions. The obstacles that these institutions faced included uncertaintyin securing cash flow for forestry projects, a potential shortage of cooperating experts and financial institutions, andinstability in the physical status of and rights to the forest properties. In the context of these issues, we describe the conditions affecting the commodification of the forest industry, which has allowed the formation of forestry business active in Japan today.

Social Safeguards in National and Sub-national REDD plus Initiatives: A comparison based on literature review Reviewed

Seiji Iwanaga, Yasuhiro Yokota, Kimihiko Hyakumura

JARQ-JAPAN AGRICULTURAL RESEARCH QUARTERLY Vol. 51 ( 1 ) page： 31 - 43 2017.1

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：JAPAN INT RESEARCH CENTER AGRICULTURAL SCIENCES

REDD+ is an approach to reduce deforestation and forest degradation, using economic incentives to influence behavior. The need for safeguards has emerged to avoid the negative social and environmental impacts caused by an overemphasis of such economic incentives. In the context of safeguards, in addition to the UNFCCC's official efforts, voluntary activities (initiatives) by many organizations have attempted to formulate principles, criteria, indicators and guidelines. In this article, we clarified the elements to enhance social safeguards and discussed how those elements are included in each initiative. We reviewed the literature on the SEPC, SESA and REDD+ SES initiatives, and clarified the focal points and problems relating to social safeguards. We found that benefit-sharing is an important aspect of social safeguards, and that more discussions are needed to enhance initiatives. The REDD+ SES initiative has received little criticism in literature to date and has the best-covered elements including "benefit-sharing" among the three initiatives. If more countries adopt REDD+ SES and more cases can be accumulated to identify problems and solutions, it could become a popular initiative in the international community to enhance the social safeguards in REDD+.

DOI： 10.6090/jarq.51.31

A Consideration on the Function of Oil Palm Plantation Development as Land Sparing for Protected Areas (Academic Article):A Case Study in Gunung Palung National Park and its Surrounding Area in West Kalimantan, Indonesia Reviewed

ONDA Nariaki, YANAGISAWA Shota, OTA Masahiko, IWANAGA Seiji

FOREST ECONOMY Vol. 70 ( 6 ) page： 1 - 21 2017

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：一般財団法人林業経済研究所

「ランド・スペアリング」は、一定の土地の生産性を高めることで、その他の土地の生物多様性保全を図る概念である。ランド・スペアリングのアプローチは、今後予想される人口増加に伴う食糧安全保障と生物多様性保全との両立のあり方を検討する目的で議論されてきた。本研究ではこの概念を援用し、集約的な土地利用の1つであるアブラヤシ農園の開発が自然保護区および地域社会に与えた影響を検討することで、アブラヤシ農園のランド・スペアリングとしての機能を評価した。インドネシア、西カリマンタン州に位置するアブラヤシ農園およびグヌンパルン国立公園に隣接する集落において、60世帯を対象とした訪問面接調査を行った。その結果、アブラヤシ農園の開発に伴い、地域住民の主たる生計手段が違法伐採を含む伐採労働からアブラヤシ農園からの収入へと変化し、国立公園の森林資源保全に寄与したことが確認され、アブラヤシ農園のランド・スペアリングとしての機能が示された。一方、世帯間においてはアブラヤシ農園収入の多寡に応じた経済的格差が認められ、今後さらに拡大することが懸念された。

DOI： 10.19013/rinrin.70.6_1

建築用木質製品利用の変遷における合板の位置づけ

岩永青史, 都築伸行, 久保山裕史

木材利用システム研究 Vol. 3 page： 15-18 2017

＜書評＞国際資源管理認証：エコラベルがつなぐグローバルとローカル

岩永青史

森林科学 Vol. 79 page： 40-40 2017

特集「現代インドネシアの森林をめぐる所有と利用」

岩永青史, 藤原敬大

林業経済研究 Vol. 62 ( 1 ) page： . 2016.3

Forest conservation and rehabilitation policies in Vietnam: their assessments and local responses

Masuda M, Iwanaga S, Kaida N, Yoshino K

Tropics Vol. 24 ( 4 ) page： 139-140 2016

国産材輸出の現状と望ましい輸出形態の検討

岩永青史

関東森林研究 Vol. 67 ( 1 ) page： 157-158 2016

The effect of forestland allocation to the livelihoods of local people in the North Central Coast of Vietnam: A case in Nam Dong district Reviewed

Thi Thuy Phuong Nguyen, Masuda Misa, Iwanaga Seiji

TROPICS Vol. 24 ( 4 ) page： 169 - 180 2016

Language：English Publishing type：Research paper (scientific journal) Publisher：JAPAN SOCIETY OF TROPICAL ECOLOGY

Forestland allocation (FLA) policy in Vietnam aimed at conserving forests and improving local livelihoods. In regard to the effectiveness of FLA, some authors reported improvements in forest cover and quality, whereas others stated inappropriate implementation process and minor impacts on household income. Hence, this study examined whether disturbances in initial stage still existed, how allocated forestlands were utilized, and how FLA contributed to local livelihoods under different forest management regimes. D village of Nam Dong district, where FLA was introduced in 1995, was selected as a case, and 78 households were randomly selected for household interviews. The results revealed that shifting cultivation, once widely reported in mountainous regions, had already ceased before our survey. Natural forests allocated to groups were mainly utilized for non-wood forest product (NWFP) collection, regardless of whether those users had an allocation. Individually allocated areas were converted to acacia and recently to rubber plantations. The rotation of acacia plantation was five to seven years with intercropping cassava in the initial stage. FLA contributed to adjusting an uneven distribution of farmland and income, but the effect remained nominal. The role of FLA in income generation was limited due to small allocation area per household (1.50ha on average). Switching to rubber trend was another reason of limited income derived from FLA. Therefore NWFP played a more significant role in the household economy than plantation yields. Investment in livestock was first preference of respondents, which suggests the importance of small-scale livestock rearing in the areas facing land shortage.

DOI： 10.3759/tropics.24.169

Status of forest development and opportunity cost of avoiding forest conversion in Ba Be National Park, Vietnam Reviewed

Other Link： https://jlc.jst.go.jp/DN/JLC/20021065888?from=CiNii

Tu Anh Nguyen, Masuda Misa, Iwanaga Seiji

TROPICS Vol. 24 ( 4 ) page： 153 - 167 2016

Language：English Publishing type：Research paper (scientific journal) Publisher：JAPAN SOCIETY OF TROPICAL ECOLOGY

This study aimed to discover the status of several types of forest and based on the opportunity costs of REDD+ to identify which greenhouse gas (GHG) emission mitigation options can be implemented in different forest types in Ba Be National Park, Vietnam. From 1990 to 2000, forest in the study area faced a high rate of forest cover loss and degradation. During the next decade from 2000 to 2010, total forest cover increased gradually. However, the natural forest area still decreased. In our household survey (n＝103), respondents reported that main drivers of deforestation and forest degradation in those areas were timber extraction for commercial or subsistence purposes, shifting cultivation, inadequate forest management, bribes to forest rangers, felling trees for firewood and bamboo shoots, and conversion to Mo (Manglietia conifera) and other perennial plants. There are some differences in those drivers between the three villages surveyed. From 2000 to 2010, several land use changes such as the conversion of poor timber forest into recovered timber forest, medium timber forest into poor timber forest and planted forest into bare land with scattered trees caused more than 8,000tCO2e emissions per year. In regard to opportunity costs, most of the avoidance options have negative opportunity costs, which mean potential benefits. Within the current carbon market price, the avoidance can be applied to reduce approximately 7,900tCO2e emissions (about 98% reduction) per year in the three communes surveyed.

DOI： 10.3759/tropics.24.153

Other Link： https://jlc.jst.go.jp/DN/JLC/20021065932?from=CiNii

Prospects and challenges of reducing emissions from deforestation and forest degradation in Central Kalimantan Province, Indonesia Reviewed

Motoshi Hiratsuka, Shyam Krishna Paudel, Seiji Iwanaga, Hirofumi Yaginuma, Amano Masahiro

International Journal of Environment and Sustainable Development Vol. 15 ( 1 ) page： 49 - 66 2016

Language：English Publishing type：Research paper (scientific journal) Publisher：Inderscience Enterprises Ltd.

Indonesia is rapidly progressing in terms of reducing emissions from deforestation and forest degradation (REDD plus) preparedness. We carried out a detailed feasibility study to develop and implement a new mechanism of the REDD plus for Central Kalimantan, a REDD pilot province of Indonesia. Several REDD plus activities were implemented in Paduran Mulia Village of Central Kalimantan. Remote sensing data was used to detect land use changes in the study area and was complemented by ground inventory to assess the actual carbon stock of the forest. The study found that land cover and uses have significantly been changed since last 30 years. Considering 2008 as a base year, we estimated that the total emission reduction would be 9,344 Gg CO2 in the next 20 years (about 450 Gg CO2/year). The results indicated the optimistic scenario with significant emission reduction if the proposed REDD plus activities were implemented successfully.

DOI： 10.1504/IJESD.2016.073334

Sustainability of Timber Production by Farm Forestry in Private Forest : A Case Study in Tasikmalaya, West Java, Indonesia Reviewed

IWANAGA Seiji

Journal of Forest Economics Vol. 62 ( 1 ) page： 75 - 83 2016

Authorship：Lead author,　Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：林業経済学会

In Java Island, Indonesia, where shows active utilization of private forest (PF) timber by timber processing industry, the relation between behaviors by the government, timber processing company, sawmill and farmer and the transition of forest area was analyzed. The most effective policy was request for acquisition of certification for a place of timber's origin. In Tasikmalaya District, the check of certification grasped the real situation of timber utilization. Meanwhile, the demand expansion of PF timber increased amount of timber production by farmers and decreased forest area. Tree planting by farmers increased forest area in 2007. However, because of continuous of purchasing price increase, timber cutting was continued at a faster rate than plantation and it decreased forest area in 2010. Furthermore, sawmills were established in associate with demand expansion and the total capacity of sawmilling was exceed timber supply in amount. As a result, sawmills fell into timber shortage. From these results, the flow "decrease of natural forest area → shortage of timber supply → utilization of PF timber → increase of PF area" and the existence of next scenario "increase of PF timber utilization → decrease of PF area" was clarified.

Effect of Oil Palm Plantation Development in Establishment Phase on Local People's Livelihood Strategies and Perception of Land Tenure in Peat Land : A Case Study in Kapuas District, Central Kalimantan, Indonesia Reviewed

IWANAGA Seiji, ANAKURA Natsuko, ONDA Nariaki, AMANO Masahiro

Journal of Forest Economics Vol. 61 ( 1 ) page： 75 - 85 2015

Authorship：Lead author,　Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：林業経済学会

Oil palm plantation has a negative impact on Global warming on particularly on peat land that is not suitable for agriculture. This survey focuses on two factors that change the source of income and economic condition of the local people in Central Kalimantan where peat land abounds, and the perception that oil palm plantation requires conversion of custom land where traditionally utilized by them. It also clarifies the impact of the establishment phase of oil palm plantations on employment and the local society. And, based on the results, we discuss desirable livelihood strategy for local people. Findings of the survey confirm that the main source of income for young households is oil palm plantations that engage them as labor while the older households' income come from managing small private rubber plantations. However, households engaged as labor in oil palm plantations also wished to own rubber plantations and were concerned about losing custom land that the oil palm plantation companies were buying. The local people are largely dependent on uncertain plantation labor for their livelihood, and as they do not have many alternative sources of income, it is necessary for them to lower any risk by retaining custom land, which is one of their important sources of income.

Circumstances and Possibility of Entry into Melaleuca (Melaleuca cajupti) Timber Market in Indonesia : Toward Generation of New Income Source for Local People in the REDD+ Project Reviewed

Carrying capacity approach to forest management in developing countries

Masuda M, Iwanaga S, Shiga K, Prasetyo L, Damayanti E

The international forestry review: Sustaining forests, sustaining people (Abstract of XXIV IUFRO World Congress, 5-11 October 2014, Salt Lake City, USA) Vol. 16 ( 5 ) page： 464-465 2014

IWANAGA Seiji, HIRATSUKA Motoshi, YAGINUMA Hirofumi

Journal of Forest Economics Vol. 60 ( 3 ) page： 25 - 36 2014

Authorship：Lead author,　Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：林業経済学会

To improve the livelihood of local people involved in the Reducing Emissions from Deforestation and Forest Degradation and the role of conservation, sustainable management of forests and enhancement of forest carbon stocks in developing countries (REDD+) project, we examined the necessary factors to incorporate Melaleuca (Melaleuca cajupti) timber production as a new income source. At PM Village, with Central Kalimantan as research target, we conducted Project Cycle Management (PCM) to investigate Melaleuca timber production. Findings clarified that the main problem was access to the timber market. Therefore, we conducted market surveys to search for and develop a distribution channel. We discovered two markets for Melaleuca timber; market of a small-diameter timber and a middle-diameter timber. Eventually, it became apparent that there was no room to enter the small-diameter market. In the middle-diameter market, a shortage of timber was occurring simultaneously with an increase in Melaleuca demand because the amount of timber available from Kalimantan (e.g., Meranti: Shorea spp.) had decreased. In PM Village, there were no middle-diameter trees, so forest management (i.e., silviculture) was identified as an objective for the area. Moreover, forest management in this area has become additionality of the REDD+ project. Accordingly, it is anticipated that Melaleuca grown in peatlands will generate profitable income for REDD+ projects in other peatland areas.

Estimation of potential GHG emission reduction through corresponded REDD plus activities in Remote Area in Central Kalimantan, Indonesia: Case study in the Paduran Area Reviewed

Hiratsuka M, Iwanaga S, Tsuzuki H, Yaginuma H

Open Journal of Forestry Vol. 4 ( 04 ) page： 338 - 348 2014

＜書評＞日本・アジアの森林と林業労働, 信州大学森林政策学研究会編, 小池正雄・三木敦朗監修, 川辺書林, 2013年9月, 335ページ, 2,160円(税込), ISBN978-4-906529-76-6

岩永青史

森林科学 Vol. 71 ( 0 ) page： . 2014

Effects of contract tree farming by timber processing companies on forest resources:A case study in Tasikmalaya, West Java, Indonesia Reviewed International coauthorship

Iwanaga S, Wijaya CI

Proceedings of 12th Science Council of Asia Conference page： 67 - 68 2013

Effect on forest of employment structure and land use in transmigration village, Central Kalimantan, Indonesia : Discussion of problems in implementing REDD plus Reviewed

Onda Nariaki, Iwanaga Seiji, Anakura Natsuko, Wijaya Chandra Irawadi, Amano Masahiro

Japanese Journal of Forest Planning Vol. 46 ( 2 ) page： 45 - 56 2013

Authorship：Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：森林計画学会

Large-scale forest development, natural forest harvesting, and oil palm planting have created employment opportunities for rural people in transmigration villages in Indonesia. However, large-scale forest development is expected to decline owing to the introduction of the REDD+ scheme. This study aimed to discuss the problems of implementing REDD+ from the perspective of the livelihood structure and land-use system in the PM transmigration village in Pulang Pisau District, Central Kalimantan Province. The majority of migrant workers in the village were engaged in forest development. In addition, the trend of occupations in Central Kalimantan Province was consistent with its history of forest development. In PM village, 55.3% of owned land was not utilized, and subsistence crop cultivation and rubber planting were conducted on a part of owned land. All cultivation and planting activities were conducted on owned or leased lands in the village; therefore, the surrounding national forest was not required to be cleared for cultivation or rubber-planting activities. Households engaged in migrant work and who had accumulated land abandoned by other villagers were involved in rubber-planting activities. Therefore, in the case of transmigration villages who have accumulated land through population exodus, assistance in tree crop cultivation would be effective to create a future cash income source as an alternative to forest development-related employment opportunities.

DOI： 10.20659/jjfp.46.2_45

Policies and resource situations of private forests in Indonesia : A case study in Tana Toraja District, South Sulawesi Province

Shift in raw materials for the wood processing industry in Java Island, Indonesia: A perspective from the post natural forest era Reviewed

Iwanaga S, Masuda M

TROPICS Vol. 22 ( 3 ) page： 119 - 129 2013

( 28 ) page： 101-112 2012.3

Trial for Local People's Forestry Establishment in Partnership with Timber Processing Company in Indonesia

Vol. 0 ( 83 ) page： 42-47 2012.1

Effects of Contract Planting by Timber Processing Companies for Farmers : A Case Study in Tasikmalaya, West Java, Indonesia Reviewed

IWANAGA Seiji

Journal of Forest Economics Vol. 58 ( 2 ) page： 14 - 22 2012

Authorship：Lead author,　Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：林業経済学会

In Java, where private forest area has been recently increasing, I examined the relations between Timber Processing Company B and farmers, who produce timber sourced from the private forests, through contract planting that implemented by Company B. A field survey in Tasikmalaya District, where the most contract planting was undertaken as compared to the rest of Java, revealed that, from 1999, farmers had been undertaking tree planting and harvesting according to the prices offered by the company. Because of the lack of supply control, the company resorted to contract planting. Contract planting was undertaken on both private land and government-owned agricultural estate land. The ratio of intercropping, which reflects diverse management strategies, was higher in the latter, as in private land without contract planting. Moreover, households that undertook planting on private land were likely to do so with a focus on timber production. These facts imply that contract planting on private land is quite favorable for the stable supply of timber production. However, there is the risk of the company purchasing the timber at lower prices because it has discretion to decide the time of harvest and purchase price.

Strategy of a timber processing company for ensuring raw materials and supply potential of private land: a case study in Tasikmalaya, West Java, Indonesia Reviewed

ポスト天然林時代におけるジャワ島の木材加工産業の資源戦略と私有林の役割 Reviewed

岩永青史

筑波大学 page： 1 - 82 2012

Production and distribution system of nipa-shingle in the Philippines Reviewed

飯田祥史, 岩永青史, 増田美砂

Bulletin of Tsukuba University Forests ( 27 ) page： 109 - 122 2011.3

岩永青史, 赤羽洋, 御田成顕

Bulletin of Tsukuba University Forests ( 26 ) page： 1 - 16 2010.3

Preference of Farmers in a Nation-wide Afforestation Program and the Possibility to Create Private Forests : A Case Study in Wonogiri District, Central Java Reviewed

IWANAGA Seiji, SHIGA Kaori, DAMAYANTI Ellyn K, MASUDA Misa

Journal of Forest Economics Vol. 55 ( 2 ) page： 1 - 9 2009

Authorship：Lead author,　Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：林業経済学会

This study aimed at examining what kind of people would support conversion of farmland to tree plantations under the framework of National Movement of Rehabilitation of Forests and Land, a nation-wide afforestation program started in 2003. Wonogiri district, an agricultural marginal area, was selected as the case and interviews to randomly selected participants of the program in 2003 were conducted at three villages. The results revealed that the differences in geographical conditions at village level, either flat easy-access or mountainous hard-access, did not much affect the performance of the program. Significant relations were found at the household level in: (1) gross income from non-agricultural sector and motivations and (2) motivations and arrangement of seedlings. And, it was clarified that the stakeholders, who could create private forest, were people who aimed at plantation itself and who planted according to "government's manual". From these results, we concluded that to increase the rate of getting mature forest, it is necessary to decrease given incentive in order to exclude people who do not aim at plantation itself.