After ten years of fieldwork in Taiwan’s remote mountain regions, researchers have identified an 84.1-meter (276-foot) Taiwania fir, now recognized as the tallest tree documented in East Asia. The team also found dense forests containing dozens of giant Taiwania firs, suggesting that other giant trees may remain hidden in Taiwan’s rugged interior.

The study, published in Frontiers in Forests and Global Change, was conducted by a team led by Rebecca Chia-Chun Hsu of the Institute of Taiwan Forestry Research, in collaboration with researchers Chi-Kuei Wang and Chung-Cheng Lee of National Cheng Kung University. Starting in 2014, the group, known as the Taiwan tree seekers, located and measured trees that had previously gone unrecorded by combining traditional field surveys with laser-based mapping and the help of citizen scientists.

The researchers found that the giant trees generally grow at elevations of about 2,087 meters and on slopes with an average inclination of 40 degrees. This combination of elevation and rugged terrain makes conventional tree surveys extremely difficult.

A Decade of Ground-Truthing

In August 2014, a systematic search began when scientists from the Taiwan Forestry Research Institute visited the Cilan conservation area to measure the ‘Chilan Three Sisters’, a group of Taiwania firs known locally but not formally recorded. The tallest tree was 69.3 meters high and had a trunk almost three meters wide. The Tree Project, a group of professional climbers from Australia, photographed the trees in 2017 and helped draw greater attention to Taiwan’s giant forests.

During a subsequent expedition near Mt. Benya and Great Ghost Lake, the team hiked for four days with their equipment to reach the study area. This experience showed how difficult it is to estimate the height of giant trees from the ground, since visual estimates can be unreliable in densely wooded, multi-layered old-growth forests. Although the team measured one tree at 71.7 meters, they concluded that ground-based surveys alone would not be sufficient for such a large and complex landscape.

LiDAR and a Problem With the Landscape

To improve their search, Hsu’s team collaborated with Wang and Lee’s remote sensing group at National Cheng Kung University and adopted LiDAR technology. LiDAR uses laser pulses from aircraft to create three-dimensional models of the forest, including estimates of tree height. However, Taiwan’s rugged topography caused the automated software to misinterpret cliffs and abrupt elevation changes as extremely tall trees.

Human reviewers proved more effective than the automated software at identifying these geological false positives. In 2020, hundreds of citizen scientists began examining the LiDAR profile images manually to distinguish real cases from artifacts. By the end of 2022, the Taiwan Giant Tree Map had identified 941 trees taller than 65 meters.

The researchers concluded that combining airborne laser scanning with crowdsourced image reviews and expert analysis can greatly reduce terrain-related errors in estimating tree heights.

Finding the “Heaven Sword”

In 2023, the mapping project led the team to a candidate for Taiwan’s tallest tree, which could be reached after traveling 20 kilometers down a river and then spending two days climbing. A direct measurement established the tree’s height at 84.1 meters, making it the tallest tree ever documented in Taiwan and East Asia. The team called it the ‘Heaven Sword of the Da’an River’. The Indigenous Rukai people have a name for trees of this kind and describe them as ones that ‘hit the moon’. By early 2026, researchers had documented 10 Taiwania firs taller than 70 meters, including two that exceeded 80 meters.

The mapping effort also brought the team back to the Great Ghost Lake region, nearly ten years after their initial visit. There, they identified about 30 large Taiwania firs growing together in an ancient stand, which the team began calling ‘temples of giants.’ In a hectare of forest near Mt. Benya, they recorded 11 individual trees exceeding 65 meters in height.

What the Giants Are Storing

The importance of these forests goes beyond their height. In 2024, Hsu’s team, in collaboration with 15 citizen scientists, surveyed Tao Tree Valley, home to Taiwan’s third-tallest tree, to determine how much carbon the forest stores. They found a carbon density of 1,384.5 megagrams per hectare, without including the root systems. The estimate is comparable to carbon-storage densities reported for some of the world’s most carbon-rich forests, including giant eucalypt forests in Tasmania. The researchers noted that their estimate did not include root systems and may have underestimated the forest’s true carbon storage.

The researchers still do not know how many other giant trees remain hidden in Taiwan’s mountains. However, the combination of LiDAR mapping, citizen science, and field verification gives them a way to search terrain that would otherwise be nearly impossible to survey systematically.

Austin Burgess is a writer and researcher with a background in sales, marketing, and data analytics. He holds an MBA, a Bachelor of Science in Business Administration, and a data analytics certification. His work focuses on breaking scientific developments, with an emphasis on emerging biology, cognitive neuroscience, and archaeological discoveries.

In recent years, forests have emerged as pivotal players in global climate mitigation efforts, representing one of the most promising nature-based climate solutions available today. These ecosystems sequester approximately 31% of anthropogenic carbon dioxide emissions annually, providing a critical buffer against the accelerating pace of climate change. However, the reliability of forest carbon credit systems—mechanisms designed to monetize and incentivize carbon sequestration efforts—has come under intense scrutiny. A groundbreaking study published in the journal Biological Diversity unveils deep-rooted methodological flaws that cast profound doubt on the environmental integrity of current carbon credit frameworks, signaling a crisis of confidence across global carbon markets.

The rigorous analysis, spearheaded by environmental scientists from Yangtze University and Beijing Normal University, meticulously dissects the complex architecture of forest carbon credit systems and identifies four principal structural weaknesses that collectively undermine their trustworthiness. Foremost among these is the use of subjective assessments of additionality, a core concept requiring that credited emissions reductions would not have occurred in the absence of the project. Present carbon credit models predominantly rely on static historical baselines to calculate additionality, yet only an alarming 6% of REDD+ credits—credits allocated under the United Nations’ Reducing Emissions from Deforestation and Forest Degradation program—provide robust empirical evidence to substantiate genuine additional carbon mitigation.

Beyond the critical challenge of additionality, the permanence of carbon sequestration—signifying the long-term retention of carbon stock in forest biomass—is grossly overestimated by current standards. This overestimation is particularly precarious in light of escalating ecological disturbances linked to climate change including wildfires, prolonged droughts, pestilence outbreaks, and inadvertent carbon leakage where forest degradation shifts to unmonitored regions. The failure to appropriately incorporate these growing risks into permanence calculations means that many credited projects likely exaggerate their true contribution to climate mitigation, presenting an illusory picture of impact.

The study further reveals that leakage accounting—the assessment and adjustment for project-driven emissions displacement—is critically underdeveloped. Prevailing methodologies apply a modest average leakage deduction of only 7%, a figure that starkly contrasts with empirical findings suggesting leakage rates ranging from 10% to a staggering 70%. Such systemic under-accounting inflates the perceived net climate benefits of these forest projects, enabling an artificially optimistic valuation of carbon credits within international markets and undermining carbon trading integrity.

Compounding these shortcomings are the conspicuous omissions of biophysical impacts such as albedo and evapotranspiration effects in carbon accounting. Forest ecosystems substantially influence Earth’s energy balance through their reflectance properties and water cycling functions. Neglecting these elements obscures the true net climate impact, as alterations in surface albedo can significantly offset the cooling benefits gained from carbon sequestration, thereby diluting the overall effectiveness of forest-based interventions in climate regulation.

The collective failure to address these intertwined issues has deep ramifications not only for the credibility of carbon markets but also for biodiversity conservation and community well-being, which are often marginalized in project implementation. Insufficient local community involvement and opaque benefit-sharing arrangements risk alienating indigenous stakeholders, raising social equity concerns, and jeopardizing the sustainability and durability of mitigation efforts.

In response to these multifaceted challenges, the research team advocates for a transformative overhaul of forest carbon credit systems through a data-driven, science-based, and integrative accounting framework. Central to this reform is the replacement of static baselines with dynamic monitoring systems that leverage high-frequency remote sensing technologies alongside advanced machine learning algorithms. This approach enables objective, continuous, and quantitative assessments of additionality, dramatically enhancing transparency and scientific rigor in credit issuance.

Addressing permanence requires the establishment of a comprehensive three-tier risk management architecture comprised of prevention, buffering, and insurance mechanisms. This tiered system proactively mitigates disturbances by integrating biodiversity conservation as a mandatory compliance criterion rather than considering it a supplemental benefit, thus embedding ecosystem resilience at the heart of carbon project governance.

Transparency and standardization are equally emphasized through the call for stringent Monitoring, Reporting, and Verification (MRV) protocols. The use of cutting-edge technologies such as Light Detection and Ranging (LiDAR) and environmental DNA (eDNA) is prescribed to ensure precise biomass and biodiversity assessments. Additionally, mandatory disclosure of datasets and verification methodologies aims to foster independent third-party audits, enhancing accountability and stakeholder confidence in carbon accounting practices.

Sociopolitical dimensions are also addressed, with the framework highlighting the critical necessity of formalized community governance structures and the institutionalization of Free, Prior, and Informed Consent (FPIC) procedures. These mandates ensure that forest-dependent communities retain decision-making power and equitable access to the socioeconomic benefits derived from carbon sequestration projects, thereby reinforcing local stewardship and long-term project viability.

While the introduction of these rigorous standards is expected to contract the overall volume of carbon credits issued—reflecting a more conservative and realistic accounting of mitigation gains—the resultant credits will embody higher integrity and trustworthiness. This qualitative transformation is paramount for forest carbon credits to evolve from contested commodities susceptible to skepticism into robust and reliable assets underpinning credible global climate governance.

The implications of this research are profound. By embedding scientific rigor and standardized risk management, forest carbon credits can realize their full potential as durable climate mitigation tools while simultaneously safeguarding biodiversity and respecting community rights. This paradigm shift promises to restore confidence among stakeholders, catalyze more effective climate finance mechanisms, and advance global efforts to stabilize the Earth’s climate system.

Ultimately, this work underscores a crucial message: nature-based climate solutions like forests must be governed by scientifically sound and socially just frameworks. Only through such commitment to transparency, accuracy, and inclusivity can these natural assets deliver genuine and lasting contributions to the fight against climate change.

Subject of Research: Not applicable
Article Title: Restoring Trust: Rebuilding the Forest Carbon Credit System Through Scientific Rigor
News Publication Date: June 17, 2026
Web References: http://dx.doi.org/10.1002/bod2.70026
References: Chen, Xiaoqian, and Shaokun Li. 2026. “Restoring Trust: Rebuilding the Forest Carbon Credit System Through Scientific Rigor,” Biological Diversity: 1–5.
Image Credits: Xiaoqian Chen, and Shaokun Li
Keywords: Environmental sciences, Carbon emissions, Biodiversity conservation, Climate change mitigation, Risk management, Deforestation, Community ecology, Albedo, Resource policy, Environmental economics, Sustainable development, Land use, Climate change adaptation, Forestry, Carbon, Environmental policy, Environmental impact assessments, Environmental management, Remote sensing, Forest ecosystems