Rethinking Wood Waste Removal with Lignin-Based Source Development: How A Wood-Vinegar Business in Taiwan Expands Cross-Sector Collaborations Towards Sustainability

Rethinking Wood Waste Removal with Lignin-Based Source Development: How A Wood-Vinegar Business in Taiwan Expands Cross-Sector Collaborations Towards Sustainability

Published: 2024.11.27
Accepted: 2024.11.27
26
Junior Researcher
Agricultural Policy Research Center, Agricultural Technology Research Institute, Taipei, Taiwan
Junior Researcher
Agricultural Policy Research Center, Agricultural Technology Research Institute, Taipei, Taiwan

ABSTRACT

While livging trees are widely recognized for their crucial role in combating climate change, the management of dead tree parts—whether from natural causes or routine pruning—also demands attention. Common practices such as landfilling or incinerating these materials can exacerbate carbon emissions by releasing stored carbon back into the atmosphere. A rising alternative model with the cradle-to-cradle mindset has been carved out by a wood-vinegar business in Taiwan, utilizing the salvaged tree parts/wood as a resource for developing value-added products. This article explores (1) how the management of discarded tree parts can be reimagined by being incorporated into a more sustainable operating mechanism reducing waste, (2) which goes further bringing more lignin-based woody plants into the picture, while (3) broadening the spectrum of collaborative partners from public agency to corporate sustainability committee articulating the carbon storage glossary. The multiple and on-going partnerships discussed here transcending agriculture and forestry may shed some light on the existing pledge scheme in voluntary sustainability initiatives with policy implications for ideal stakeholders contributing to collective action with social impact.

Keywords: cradle-to-cradle, salvaged wood, lignin-based, sustainability

INTRODUCTION

Broken branches, damaged tree trunks lying on the ground—these are familiar scenes during the monsoon or typhoon season in Taiwan, the handling of which often involves timely removal from the perspective of ‘waste’ treatment. Take the capital Taipei City for example, the city government’s Parks and Street Lights Office (2015) has developed specific guidelines to process typhoon-damaged street/park trees: after preliminary wood classfification reserving wood species of higher economic value for resale, the rest would be delivered to the dumpsite (branches/trunks with diameter wider than 15 centimeters) or incineration (leaves and branches less than 15 centimeters in diameter). Similar rules have also been applied to other open fields such as schoolyards (see Figure 1 for demonstration), with extra effort and expenditure paid to remove the fallen or trimmed/pruned tree parts from the site. 

Either landfilling or incineration, however, has aroused dabate over the respective greenhouse gas (GHG) emission and impact on local air quality (Gómez-Sanabria et al., 2022), especially in the on-going pursuit of sustainability towards decarbonization across various sectors all around the globe. While the strategy of afforestation is believed to combat the rising GHG levels for its role in carbon capture, it seems to be at odds with this routine of rotting or burning discarded wood as waste, releasing carbon to the atmosphere (Morris, 2017). Therefore, the question is: what could possibly be changed for the better?

This article digs into one particular case that attempts to provide an answer by rethinking the management of discarded wood and turning them into value-added products, embedded in an old rural town’s past of charcoal production. The following sections are carved out from companionship with the studied rural entrepreneurial business engaged in Taiwan’s emerging circular economy and regional revitalization policy schemes through field research. As governance along with public policy for sustainable development tends to employ a cross-sectoral approach in itself (Marín-González et al., 2022), the work here would see this case from the perspective of cross-sector collaborations instead of mere technical breakthrough—particularly how it weaves together more and more public and private stakeholders in the region as well as across the country that may shed a new light on the discussion of the burgeoning environmental, social, and corporate governance (ESG) practices towards sustainability.

REIMAGINING THE MANAGEMENT OF DISCARDED TREE PARTS

Other than being burned down only to ashes or going into landfill as rotting logs, the tons of raw wood materials from the mentioned removal tasks may find new meanings and opportunities through the idea of whole-tree utilization. That is, the collection of tree trunks and branches as seen in Figure 1 may not lead to the end/grave in the traditional waste disposal process, but from that point be incorporated into a larger circle of reusing and production.

While this principle of reuse regarding tree pruning waste often engages compost/fertilizer (Reyes-Martín et al., 2022) or pulp for papermaking (Duarte da Silva et al., 2013), the case here builds on the place-based prior practice of woodworking and charcoal production. Not pointing to the typical forest product of wood charcoal used as fuel as defined by Food and Agriculture Orgainzation of the United Nations (2022), it is the processing of biochar along with its byproduct of wood vinegar that is at the center of this article, embedded in the background story of international knowledge and technology transfer in the beginning of this century.

The technology transfer of wood-vinegar extraction

Also going by the name ‘mokusaku [もくさく]’ in Japanese, the attempt to extract wood vinegar may not be a new concept nor endemic in terms of thermochemistry, but the localized methods and improved model have continued to be updated in various parts of the world (Okabe et al., 2007; Sangsuk et al., 2023). It all starts with the pyrolysis process usually in the kiln settings in which woody biomass derived from trees is heated to form charcoal (namely carbonization) accompanied by forming vapors at the same time as a chemical change. The liquid smoke generated from the gas and combustion under airless condition through destructive-distillation could thereby be collected and condensed in cold as wood vinegar (Matthew & Zakaria, 2015), a yellowish brown or dark brown liquid known as pyroligneous acid (PA).

While large-scale charcoal production in Taiwan could be dated back to the early 20th century under Japanese colonial rule (Wang, 2017), the realm of its by-product had remained a foreign land to the local charcoal producers/factories. It is not until a series of agricultural science and technology projects engaging industry-academic cooperation supervised by Taiwan’s Ministry of Agriculture (MOA) from 2000 onwards that the mentioned extraction and distillation technology itself be taken to Taiwan (TFRI, 2016). By consulting Japanese scholars on bamboo charcoal and extraction of bamboo vinegar as novel forms of forest products back then, a particular earth mound kiln design was experimented and explored among bamboo forests across the country. The disinfectant and odor removing qualities that come with PA (Grewal et al., 2018) obtained from the pyrolysis of bamboo trees are believed to add value to the local natural resource and help revitalize the regional industry.

Meanwhile in Hsinchu County, Northwestern Taiwan where the number of charcoal factories once reached its peak supplying the highest-quality products for the whole island and Japan’s military/living needs (Wang, 2017), the solid fuel industry has slumped over the decades mainly due to the emerging use of gas, changed planning of land development and several combined reasons (Cheng & Tang, 2004). Instead of closing down the charcoal business like many others in the area did, a former wooden furniture and charcoal factory in the rural town of Dawoko in Hsinchu County has been inspired by the above technological progress involving carbonization and vapor collection to gradually turn the tables transforming itself into the studied case of wood-vinegar business today by investing in the extraction device and technology know-how handled by the domestic Industrial Technology Research Institute (field interview). Not going into the technical details here, the article aims to draw upon an overview of the processing flow to illustrate how the game-changing business operating mechanism established could provide an alternative solution to the trajectory of discarded tree parts for the better.

No wood left behind: Recycling, reusing and upcycling salvaged raw wood materials

What really distinguishes this studied rural business from others first is the material source of choice. It offers free-of-charge help for various sites to take the burden of removing tonnes of dead raw wood from natural disasters or regular tree trimming—a task that was supposed to cost extra for involving logistics or horticulture companies. While any other firm working with raw wood could have chosen imported materials from overseas, such a business choice may not be a problem-solving one concerning the environmental impact. Here the recycling of salvaged wood materials is sourced from outdoor fields mostly in (but not cofined to) the surrounding townships and nearby counties (field notes), and would be succeeded by the following processes:

  1. Classification: each batch of wood materials would be sorted based on (a) tree species (considering importance in economic and ecological value), (b) hardwood or softwood types, (c) diameter in tree branches/trunks, (d) quality, etc., into different groups for diverged purposes.
  2. Preliminary treatments after collection: sundrying and being precut for storage.
  3. Chunky log reservation (if applicable): logs and branches wider in diameter or higher in economic value would be reserved for hand-made woodwork. The experienced artisans under the firm as well as voluntary apprenticies from nearby towns together are dedicated to producing solid wood furniture pieces large and small for sale online and onsite.
  4. Carbonization: the rest of the wood scraps would go into the earth mound kiln to produce (a) biochar while collecting (b) the crude condensed PA with intrinsic smoky smell at the same time. Both are applicable for being used as organic fertilizers in farming practices, while the collected biochar could also be packaged as dehumidifier packets. The latter would go through another series of sedimentation, filtration and distillation to come up with isolated refined wood vinegar that is more stable and skin safe. With the professional kiln system at play, the biochar production process would not release carbon dioxide to the open air.
  5. Into production lines and the consumer market: the refined/finely distilled wood vinegar would be later formulated as the main active ingredient with other plant-derived ones by the third party of partnered chemical engineers through research and development (R&D) partnerships. The formula would be manufactured into lines of customizable eco-friendly cleaning products suitable for all purposes. Over the past decade, the studied business has already accumulated a large consumer following, especially among pet-friendly households with odor removing needs.
  6. Back to the roots: besides retail distribution, the end products would be delivered back to the sites from which the raw wood materials are sourced, through donation or procurement. For instance, in cases where salvaged tree parts are collected from schoolyards, a proportion of the biochar products would be donated to the campus working as soil fertilizer, odor absorber or dehumidifier, along with batches of cleaning products for school faculty and students to use and fresh up the classrooms.

Take a batch of tree branches and chunks trimmed down from a university in Hsinchu City for example, in terms of scale and the conversion of wood waste via pyrolysis. Five tons of the wood materials undergoing the above processes could come up with roughly one ton of biochar and one ton of crude wood vinegar altogether. If the batch were to be delivered to the incineration plant facility as it used to be, it would cost the school US$1,000-3,000. But the processed materials with disinfectant and odor removing qualities could go on to be manufactured into cleaning products ranging from mosquito repellents to hand sanitizers, with values equivalent to at least US$12.5 thousand at market price (field notes).

In stark contrast to the frequently known cradle-to-grave waste disposal process where the dead tree parts are to be thrown away, here they would make it into a circle of reusing and reducing the ‘waste’, processed into new value-added products and returning to where they are sourced in the first place—certainly a cradle-to-cradle philosophy (see Figure 2) making the end products ‘circular.’ A more detailed diagram would be illustrated in the later section with site-specific examples.

MORE TO COME: WOODY PLANTS and beyond

As wood by definition is “a structural tissue found in the stems and roots of trees and other woody plants (Maiti et al., 2016, Chapter 7),” one characteristic shared in common among these plant-based materials is the composition of lignin (the key structural materials in the formation of the plant cell wall especially in wood and bark), cellulose and hemicellulose that altogether go on to form PA during pyrolysis (Matthew & Zakaria, 2015). The same logic of wood vinegar extraction could hence work for other woody plants not necessarily growing with superlative height or wide trunk diameter as people tend to imagine. This section illustrates how the list of lignin-based materials eligible for extracting the effective ingredient continues, attributing to experimental practices and co-ventures undertaken by rural stakeholders from various backgrounds with the same objective of reducing waste. An overview of three partnerships is covered here, the trajectory of which has indeed opened more co-opportunities and been expanding the range of accessible material sources.

Crop residues from the local farming practices

In the rural town of Dawoko in Hsinchu County where the main protagonists in this case study are situated, the local agricultural activities are also faced with the waste dilemma. Common crop residues from fruit trees or paddy fields are often considered of no use by local producers, most likely to be openly burned or idly placed (field notes). At the forefront of building ties with local producers, the District Agricultural Research and Extension Station (DARES) under the umbrella of MOA herein plays an intermediary role linking together the studied business lending out the biochar kiln and the local cooperative to experiment on reusing the harvest or pruning waste.

To begin with, pruned branches from pear trees (see Figure 3) are collected, classified, sundried and precut before heading into the kiln, which goes on to collect the smoke to be condensed into PA. Rice husks from the harvesting season are also treated following the same route. In return for the input of crop residues, the processed biochar (see Figure 4) and crude wood vinegar are later sent back to the producers to be used as soil fertilizer or plant growth enhancer; safe to say, what is from the field goes back to the field in this cycle of reusing crop residues as a source of lignin-based raw materials. The mechanism not only eases the burden for local producers but also creates a positive circular community cutting down waste. From there, the collaborative spirit goes on to include more stakeholders beyond the county border in the following paragraphs.

Fighting the war against invasive alien plant species

Taiwan as a mountainous island with various mountain and hill ranges either public or private owned promises to be a nursery for lignin-based materials. Not just the well-known species like cypress trees, there are many other unexpected ones in this category. An example of the latter includes a rising invasive plant Mikania micrantha Kunth native to the sub-tropical zones of North, Central, and South America yet now thriving across Taiwan, also known as the bitter vine and considered among 100 of the world's worst invasive alien species (Lowe et al., 2000). Once the fast-growing vine has climbed onto and covered any other vegetation, it can smother the native trees and agricultural crops, killing plants and/or decreasing yield, all in all posing a threat to the local biodiversity and ecosystem (CABI International, 2022). The official approach by the authorities in forest management, namely Taiwan’s then Forestry Bureau (the current Forestry and Nature Conservation Agency, FANCA under the MOA framework) had called for voluntary vine removal from the public across the country with cash incentives. Such removal tasks, however, are not only budget-consuming but also inevitably continue to accumulate many collected vines (as seen in Figure 5) in various counties weighing a ton, usually followed by the traditional treatment in wood waste management, that is going into landfilling/incineration afterwards. In precise numbers from 2009 up to fiscal year 2022, 11,116 tons of bitter vines had been collected costing more than US$1.6 million on purchasing from the public, exclusive of other fundings for local governments on this matter at more than US$29.7 million (Public Television Service Foundation, 2023). How to protect the local ecosystem in the cost-effective and more sustainable way has certainly become a challenge.

Fighting the war against invasive alien plant species

Taiwan as a mountainous island with various mountain and hill ranges either public or private owned promises to be a nursery for lignin-based materials. Not just the well-known species like cypress trees, there are many other unexpected ones in this category. An example of the latter includes a rising invasive plant Mikania micrantha Kunth native to the sub-tropical zones of North, Central, and South America yet now thriving across Taiwan, also known as the bitter vine and considered among 100 of the world's worst invasive alien species (Lowe et al., 2000). Once the fast-growing vine has climbed onto and covered any other vegetation, it can smother the native trees and agricultural crops, killing plants and/or decreasing yield, all in all posing a threat to the local biodiversity and ecosystem (CABI International, 2022). The official approach by the authorities in forest management, namely Taiwan’s then Forestry Bureau (the current Forestry and Nature Conservation Agency, FANCA under the MOA framework) had called for voluntary vine removal from the public across the country with cash incentives. Such removal tasks, however, are not only budget-consuming but also inevitably continue to accumulate many collected vines (as seen in Figure 5) in various counties weighing a ton, usually followed by the traditional treatment in wood waste management, that is going into landfilling/incineration afterwards. In precise numbers from 2009 up to fiscal year 2022, 11,116 tons of bitter vines had been collected costing more than US$1.6 million on purchasing from the public, exclusive of other fundings for local governments on this matter at more than US$29.7 million (Public Television Service Foundation, 2023). How to protect the local ecosystem in the cost-effective and more sustainable way has certainly become a challenge.

The Hualien Division of FANCA is one of the government agencies that have been seeking ways to reuse this invasive alien plant species under the framework of an emerging project, and vinegar extraction out of it stands as a starting point exloring the possibility of adding value to the collected vines while cutting down waste. The public agency first teamed up with the academia to conduct research on the direct usage of bitter vinegar on human body as mosquito repellent (Lu et al., 2016), showing good activity against Staphylococcus aureus with a high susceptibility percentage (99.9%). With the prior knowledge and positive research results at hand, it went on to work with the rural business studied here to commercialize and manufacture a whole new line of bitter-vine-vinegar-based cleaning and disinfectant products to the consumer market in the formulation of herbal ingredients only. The project launches 7 products ranging from laundry detergent and odor-removing multi-purpose cleaner to body wash and disinfectant hand cream.

On average, every liter of finely distilled vinegar could be collected from 1.4 liter of roughly distilled one produced by around 42 kilograms of bitter vines (Yu, 2023). The conversion rate may not be the highest among all lignin-based raw materials, but it does help tackle the problem of managing collected vines and create new rules for plants that are widely considered of no value or use. This attempt to reuse the collected woody plants also led to the public agency’s move to sign a Memorandum of Understanding (MOU) with the studied business in 2023, marking as how public and private actors could work hand in hand for the same goal of reducing waste as well as value addition with applicable technology.

Into the woods of ESG collaboration

And not just public actors are stepping in, private partners have also voluntarily joined this party. Besides working with actors in the primary sector as stated earlier, another private partner that may seem surprising at first glance is a subsidiary of the electro-optical and semiconductor manufacturing corporation BenQ-AUO Group specialized in display technologies headquartered in Taiwan’s Silicon Valley, namely Hsinchu Science Park. But looking into the site-specific information in more detail, including how the subsidiary is located roughly 34 kilometers south of the wood-vinegar business, it only makes the former an ideal local rural stakeholder to work with. And it is the intersection of these businesses—a vast mountainous area in Beipu, Hsinchu County for industrial land use spanning 30 to 40 hectares purchased by the corporation two decades ago functioning as the corporate R&D training and convention center that has made the collaboration possible and rolling. Not a one-time investment, this collaboration has become a lasting circular use of the wood materials within the field’s boundary and been incorporated into the corporate supply chain relationships.

To be more exact, the raw materials targeted in this case come from the private forests surrounding the educational training and convention center, the name Mabuville of which means hemp forests in Chinese with half of its covered area to be conservation of native hemp trees [Trema orientalis (L.) Blume], camphor trees [Cinnamomum camphora (L.) Presl] and many more. With the same logic of no wood left behind, the regular thinning practices from managing the nature trails in the woods lead to the ideal reusable resources here, namely removing a proportion of the trees to provide more growing space for the remaining ones. Each year, the tree logs collected from the forest thinning could weigh up to ten tons, which used to go into landfill or incineration creating no further benefits (field notes). By participating in the reuse mechanism and production cycle discussed throughout this article, the batches of raw wood materials have hereby been turned into hundreds of thousands of bottled cleaning products and sets of sturdy solid-wood furniture customized to the corporate needs on various levels.

Firstly, the product development caters to the nature of the training and convention center’s lodge and functions venues in terms of product range and unique formula on demand. A set of 6 cleaning and personal hygiene products including shampoo, body wash, body lotion and more is produced blending the wood vinegar extracted from the site-specific woody materials, ready-to-use and refillable in the accommodation facility open to the corporate employees and visitors alike. The solid wood stools and chairs made of the same source also stand as statement pieces in the center’s lobby and café area, as well as in private rooms.

Another appealing aspect is how this collaboration speaks directly to the corporate sustainability vision for seeking “eco-friendly alternatives to chemical treatments”, “creating positive influence on the local biodiversity and conservation,” and “driving the expansion of circular economy…such as designing and selling circular products, recycling process materials, and reducing waste (AUO, 2024).” The cleaning products developed here get to not only return to the place of origin again, but also enter the consumer market under the subsidiary’s self-owned brand marketing the niche of naturally derived green products in stark contrast to other cleaning supplies on the market full of fossil fuel-based ingredients. What’s more, by working with the chief sustainability officer (CSO) for the whole corporate group who also supervises the field of Mabuville, the collaboration goes on expanding its influence on the wider networks of subsidiary companies and factories under the same manufacturing group through internal ‘green procurement,’ that is purchasing goods and services with a reduced environmental impact. In the first half of this year (2024) alone, five tons of the PA-based end products have been delivered to the mentioned semiconductor factories across the country (field interview) and would continue to be distributed. The scale illustrates how the reuse mechanism has already been incorporated into part of the corporation’s internal structure rather than serving as a short-term investment. Together, the actions of reusing the raw wood from on-site thinning practices have earned the parties both 3rd Winner in FY 2023 Social Innovation and Buying Power Procurement Award, and Special Award in Environmental Sustainability presented by Taiwan’s Ministry of Economic Affairs (2023), and continue to be promoted as one of the leading ESG projects in Taiwan (CommonWealth Magazine, 2023).

Finally, turning the thinned tree parts within the subsidiary’s boundary into biodegradable solid-wood furniture to be used on site also gets to speak the corporate carbon-related glossary, one of the key factors winning over the corporate sustainability committee. As it is understood that every part of a tree stores carbon, the latter could go on to be stored longertimes not releasing to the atmosphere as long as the wood materials are not burnt to ashes or decayed (USDA, 2020). The duration of carbon storage in wood products taking the form of houses or furniture derived from forests sustainably managed may even last centuries, as outlined by the Intergovernmental Panel on Climate Change (IPCC) of the United Nations (2007). The knowledge base allows the wood-vinegar business to also provide the service of calculating the stored carbon in the artisan-handmade wood furniture under the IPCC Guidelines (MOA, 2008), estimated with information on each batch of raw wood materials, including tree species, wood type, volumn, dry weight and so on—all already covered by the preparatory routines in management of the collected raw materials as depicted in the second section of this work. 

This on-going collaboration since FY 2023 categorized as sustainable actions of forest management and circular economy by the corporate annual sustainability report has demonstrated vividly the cradle-to-cradle philosophy, namely how the circular products have been processed from waste and continued the journey back to where they are sourced (see Figure 6 for more on-site details), all in all creating positive and renewable cycles. With sustainability at heart and technology at work, the studied business has certainly come a long way from lower-revenue charcoal production to the entire value chain of green products.

DISCUSSION AND CONCLUSIONS: FUTURE ENDEAVORS BRIDGING BUSINESS AND SUSTAINABILITY

Returning to title of this article in a nutshell: the rural business studied here has approached what was considered wood waste in the past as reusable lignin-based resource inspiring development of new products and a new niche circular economy market. Circular use of the salvaged lignin-based materials by the extraction and purification technology has spanned consumer fields of biotechnology, cleaning supplies, hygiene and skincare, and likely many more to come. More importantly, it has not done so all by itself. Starting from the technology transfer to locating the raw material suppliers, it takes a whole village of both public actors engaging research institutes or the academia and private actors such as agricultural producers and other business entities to contribute to the wood-derived upcycling.

By looking into and beyond the alternative perspective of waste management behind the studied case, the point of this article is to illustrate how the shared sustainability goals such as cutting down waste and nature/ecosystem conservation could multiply the positive influence through solution-oriented partnerships, bringing together a larger network of stakeholders transcending agriculture, forestry and manufacturing. Especially with the rising flow of ESG commitment leading various types and sectors of businesses today, the converging field may open up more opportunities in the collective pursuit of sustainability. How to help facilitate the larger picture of ideal stakeholders working together for the same goal and making the effort easier coming along may be the imminent challenge, with implications for future endeavors enrolling stakeholders in both reusable material supply and technology advancement, as well as corporations with capacities for exerting the ESG-related influence.

Identifying and matching ideal stakeholders

To put sustainable waste management to good use—that is reducing, recycling and reusing, pairing optimal technologies (including but not confined to the wood-vinegar extraction discussed here) with the potential source of reusable raw materials would be a good starting point creating positive change from landfilling/incineration. To ever alter the status quo, the stakeholder mapping shall consider who gets to have the most positive influence on the existing bulky waste collection, and that would lead to local public agencies—more precisely Departments of Environmental Protection at local level in Taiwan as prioritized stakeholders that can make a difference to the current waste management model. Trial projects working through public-private partnerships shall be a viable move, with the shared objective of cutting down waste and generating more value that could give back to the community/society.

How cross-sector ESG projects could potentially take shape

As the buzzwords surrounding ESG strategies have been transforming the corporate world along with the common pledge to conserve biodiversity ever since the United Nations Biodiversity Conference (COP15) took place (Attwell, 2023), the internal nature of such projects in tangible actions, on the contrary, seems to be rarely seen. The work here illustrates the on-going ESG collective actions may address and complement this narrative in Taiwan and suggest how enterprises do not have to do it alone. It is proved that the environmental and social considerations of reducing waste and forest conservation do act as the common ground for the studied rural business and a larger corporation working together towards a more sustainable waste management model plus an entire value chain of producing green cleaning products.

With all, not all business entities have the similar internal organizational structure that could enable the circular use on site as with the discussed corporate case scenario here. But it is also this void that might allow inviting more light in and put the studied wood-vinegar business at the intermediary position able to help match nonprofit third parties of reusable raw material suppliers (such as public parks and schools as mentioned in previous sections, to name a few) with corporations willing to invest in the shared goal exerting the positive social impact through sustainable procurement or sponsorship. Such a mechanism of customizable pact following the above stream of matching ideal stakeholders could create a win-win situation that shall benefit all parties involved. This way, it also speaks to the current proposal by Taiwan’s MOA (2024) seeking to foster ESG projects targeting ecosystem conservation, rural villages and livelihoods, with potentials for more rural-urban linkages by bridging together interested parties including but not confined to rural stakeholders.

REFERENCES

Attwell, W. (2023, October 26). Comment: Why biodiversity is about to go mainstream in ESG investing. Reuters. https://www.reuters.com/sustainability/land-use-biodiversity/comment-why...

AUO Corporation. (2024). AUO 2023 Annual Sustainability Report. Retrieved from https://www.auo.com/upload/media/sustainability/CSR/AUO-2023%20Sustainab...

CABI International. (2022). Mikania micrantha (bitter vine). In CABI Compendium. https://doi.org/10.1079/cabicompendium.34095

Cheng, C.Y. & Tang, H. P. (2004). Exploratory research on the charcoal production industry in Hsinchu region. Hsinchu City Archives Quarterly, 29: 44-63.

CommonWealth Magazine Editorial Board. (2023, October 12). When corporations become partners in catalyzing regional revitalization: Three leading cases. CommonWealth Magazine. https://smiletaiwan.cw.com.tw/article/6685

Duarte da Silva, MJ., Bezerra, BS., Gomes Battistelle, RA. & De Domenico Valarelli, I. (2013). Prospects for the use of municipal tree pruning wastes in particleboard production. Waste Management & Research, 31(9):960-965. doi:10.1177/0734242X13495101

Food and Agriculture Organization of the United Nations [FAO]. (2022). FAO Yearbook of Forest Products 2020. FAO Publishing. https://doi.org/10.4060/cc3475m

Gómez-Sanabria, A., Kiesewetter, G., Klimont, Z., Schoepp, W. & Haberl, H. (2022). Potential for future reductions of global GHG and air pollutants from circular waste management systems. Nature Communications 13(106). https://doi.org/10.1038/s41467-021-27624-7

Grewal, A., Abbey, L., & Gunupuru, L.R. (2018). Production, prospects and potential application of pyroligneous acid in agriculture. Journal of Analytical and Applied Pyrolysis, 135: 152-159. https://doi.org/10.1016/j.jaap.2018.09.008

Intergovernmental Panel on Climate Change of the United Nations [IPCC]. (2007). Increasing off-site carbon stocks in wood products and enhancing product and fuel substitution. Retrieved from https://archive.ipcc.ch/publications_and_data/ar4/wg3/en/ch9s9-4-2-4.html

Lowe, S., Browne, M., Boudjelas, S. & De Poorter, M. (2000). 100 of the world’s worst invasive alien Species: A selection from the Global Invasive Species Database. World Conservation Union (IUCN).

Lu, K. Z., Lin, T. W. & Hu, Z. H. (2014). Pyroligneous acid extracted from bitter vine proved effective against midges. Taiwan Forestry Journal, 40(5): 58-65. https://ga.ndhu.edu.tw/var/file/6/1006/img/3921/564591850.pdf

Maiti, R., Parra, A.C. & Rodriguez, H.G. (2016). Wood characteristics. In Maiti, R., Rodriguez, H.G. & Ivanova N.S. (Eds.), Autoecology and ecophysiology of woody shrubs and trees: Concepts and applications (pp. 83-110). John Wiley & Sons, Inc.

Mathew, S. & Zakaria, ZA. (2015). Pyroligneous acid-the smoky acidic liquid from plant biomass. Applied Microbiology and Biotechnology, 99(2).

Marín-González, F., Moganadas, S.R., Paredes-Chacín, A.J., Yeo, S.F. & Subramaniam, (2022). Sustainable local development: Consolidated framework for cross-sectoral cooperation via a systematic approach.  Sustainability, 14, 6601. https://doi.org/10.3390/su14116601

Ministry of Agriculture [MOA], Taiwan. (2008). Estimation of carbon sequestration capacity. Retrieved from https://www.moa.gov.tw/ws.php?id=17871

Ministry of Agriculture [MOA], Taiwan. (2023). Fostering ESG projects in the agricultural sector. Retrieved from https://www.moa.gov.tw/theme_data.php?theme=news&sub_theme=agri&id=8943

Morris, Jeffrey. (2017). Recycle, bury, or burn wood waste biomass?: LCA answer depends on carbon accounting, emissions controls, displaced fuels, and impact costs. Journal of Industrial Ecology, Yale University, 21(4): 844-856.

Ministry of Agriculture, Taiwan. (2024). ESG projects in the agricultural sector. Retrieved from https://www.moa.gov.tw/theme_data.php?theme=news&sub_theme=agri&id=8943

Okabe, T., Inamori, Y., Morita, Y., Fukuda, K., Arii, T., Anzai, E. & Fuku, T. (2007). Development of mokusaku oil obtained by pyrolysis of wood. Transactions of the Materials Research Society of Japan, 32(4): 1163-1166.

Parks and Street Lights Office, Public Works Department, Taipei City Government. (2015). Guidelines on Management of Storm-Damaged Trees. Retrieved from https://pkl.gov.taipei/cp.aspx?n=04CDA9075D68308A

Public Television Service Foundation. (2023). Pyrolysis of bitter vine: Turning green cancer into green gold. Retrieved from https://ourisland.pts.org.tw/content/10019

Reyes-Martín, M.P., Ortiz-Bernad, I., Lallena, A.M., San-Emeterio, L.M., Martínez-Cartas, M.L. & Ondoño, E.F. (2022). Reuse of pruning waste from subtropical fruit trees and urban gardens as a source of nutrients: Changes in the physical, chemical, and biological properties of the soil. Applied Sciences, 12(1):193. https://doi.org/10.3390/app12010193

Sangsuk, S., Buathong, C. & Suebsiri, S. (2023). Modified Iwate kiln for production of good quality charcoal and high volume of wood vinegar. Fuel Communications, 17. https://doi.org/10.1016/j.jfueco.2023.100095.

Taiwan Forestry Research Institute [TFRI], Ministry of Agriculture. (2016). New thinking in modern agriculture: Utilization of biochar and wood/bamboo vinegar. Forestry Research Newsletter, 23(6): 6-9.

United States Department of Agriculture [USDA]. (2020). Forest Carbon FAQs. Retrieved from https://www.fs.usda.gov/sites/default/files/Forest-Carbon-FAQs.pdf

Wang, H. H. (2017). The development of charcoal industry in Hsinchu state under the Japanese colonial rule of Taiwan. Taiwan Historica, Academia Sinica, 68(4): 81-116.

Yu, S.F. (2023, January 05). From Green Cancer to Green Gold: Transforming bitter vines into disinfectant cleaning products. AgriHarvest. https://www.agriharvest.tw/archives/95615

 

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