How China Is Turning Mangroves and Seagrass Into Governable Carbon Assets

China’s push toward carbon neutrality by mid-century has pulled the ocean into the center of its climate machinery, and a new study examines how that transformation actually works on the ground. Published in Regional Environmental Change, the research traces how blue carbon—the carbon stored in mangroves, salt marshes, seagrass meadows, and fisheries-related sinks such as seaweed and shellfish—has moved from a broad ecological aspiration to an operational policy domain with accounting standards, measurement protocols, and local pilot projects. The central argument is striking: blue carbon is not a pre-given natural object that policy simply adopts. Instead, it is iteratively defined, quantified, verified, and recalibrated through policy narratives, standard-setting, methodological rule-making, and local experimentation. The ocean, in other words, has been re-coded as a governable arena expected to deliver measurable mitigation outcomes under the country’s dual-carbon agenda of peaking emissions and achieving neutrality.

The study, authored by Wanhao Zhang, draws on Jasanoff’s concept of sociotechnical imaginaries—shared visions of desirable futures that organize knowledge production and institutional arrangements. Using this lens, the analysis asks how uncertain marine ecological processes become things that administrative systems can count, compare, supervise, and hold accountable. The empirical foundation combines thematic analysis of national and coastal local policy documents, industry standards, accounting guidelines, and regional methodologies with semi-structured interviews conducted between February and July 2025 with twelve domain experts spanning policy design, marine carbon sink research, and market-facing practice in project development, verification, and trading. The author is explicit about the sampling logic: experts were recruited purposively, not randomly, to assemble strategically relevant expertise rather than statistical representation, and the study deliberately captures an institutional field in rapid evolution rather than a settled governance system.

Four main findings emerge from the analysis. The first concerns how blue carbon is constructed as a governable climate space by design. National policy documents increasingly write mangroves, salt marshes, and seagrass beds into action repertoires that link ecological restoration to mitigation goals, baseline surveys, monitoring requirements, and capacity-building tasks. But this framing becomes institutionally consequential only when calculability is built, and that is where standards matter most. The implementation of HY/T 0349-2022, a national technical standard effective from 1 January 2023, is described as pivotal: by placing multiple marine sequestration processes within a unified accounting frame, it allows local governments, project developers, and platforms to claim their numbers are produced under a national standard and are therefore traceable and comparable in principle. Standards here function as metrological infrastructure—the shared boundaries, indicators, and procedural logics through which heterogeneous coastal processes become administratively recognizable.

The second finding describes what the author calls a two-wheel structure. At the center, national policy provides direction and a unified accounting language; around it, coastal jurisdictions experiment with device-based arrangements that make that language operable. This is not a simple top-down implementation story. Local pilots often proceed precisely because the rules are not fully closed, and their visible outputs—project records, transaction traces, compensation cases, platform listings—generate concrete pressure points that feed back into institutional refinement. Along the coastal wetland pathway, Zhanjiang’s mangrove practices make the accounting-to-transaction chain demonstrable, Shenzhen embeds mangroves into carbon-inclusion schemes through local accounting guidance, and Xiamen links trading, finance, and restoration through platform and fund-like arrangements. In fisheries-related sink enhancement, experimentation looks more portfolio-like, bundling protocols, trading trials, pledge loans, judicial compensation, and insurance to complete incentive and risk-governance functions when verification is difficult and returns are uncertain.

The third finding directly challenges a common assumption about environmental markets. The bottleneck to market-facing blue carbon in China is not a lack of willingness to trade. It is whether blue carbon can be made verifiable, regulatable, and affordable to maintain once pulled into high-accountability settings such as trading, offsetting, or judicial compensation. The entry of mangrove-related methodologies into the China Certified Emission Reductions voluntary regime in October 2023 marks a transition from pilotable idea to rule-mediated eligibility. Yet methodology building is a continuous compromise between environmental integrity and operability. The 2025 methodology release for seagrass restoration, which explicitly favors practicality through the use of default parameters, illustrates the trade-off: if monitoring, reporting, and verification become too expensive or data access too demanding, a scientifically ambitious method can become governance-inert. As the interviews show, verification is where scientific uncertainty becomes an implementation issue—researchers worry about parameter stability and model applicability, while local governments and firms worry about budgets, staffing, and the way uncertainty amplifies into asset-value and compliance risks.

The fourth finding identifies the structural bottlenecks that persist across the whole system: cross-department coordination, uneven local capacity, and unresolved risk allocation. Blue carbon cuts across environment, natural resources, forestry, agriculture, and carbon market administration, with baseline data, sea-use tenure, project approval, verification, and trading regulation often sitting in different institutional hands. When competence boundaries do not align, coordination costs rise and uncertainty travels along the chain, only to be magnified in trading or compensation settings where accountability is high. The long-horizon nature of many projects sharpens the problem: restoration outcomes are exposed to storms and ecological disturbances, long-term stewardship depends on local fiscal and technical capacity, and where restoration interferes with existing aquaculture and sea-use arrangements, blue carbon becomes a negotiated question of compensation and redistribution rather than a mere accounting exercise.

One of the study’s most suggestive interpretive moves is its reading of local financial and legal instruments. Insurance, index insurance, pledge loans, funds, and judicial compensation appear repeatedly across coastal pilots, and the author argues their frequency is diagnostic rather than celebratory. They are institutional attempts to distribute shocks, stabilize expectations, and make participation thinkable under long time horizons and uncertain returns. Their presence does not mean risk is solved; it signals where the governance system is most exposed. Sustainable market-facing blue carbon, on this account, depends on whether such risk-sharing and revenue-stabilization mechanisms can become replicable—visible, predictable, and institutionally backed enough that developers, local governments, verifiers, and buyers can discern credible responsibility boundaries.

The analysis also reframes what local experimentation is for. Rather than treating pilots as mere implementation tests or market demonstrations, the study characterizes them as feedback infrastructures. By putting accounting rules, verification arrangements, and incentives into practice, pilots expose problems that remain invisible in policy texts—inconsistent baselines, coordination burdens, verification gaps, unstable demand, and unclear supervisory interfaces. These frictions constrain local scaling, but they generate practical knowledge that informs subsequent standard-setting. Local assemblages therefore have a dual role: they publicly enact the claim that blue carbon can be counted, financed, compensated, or exchanged, while simultaneously revealing the institutional costs of making those claims credible. Calculability itself emerges as both anchor and boundary—it enables participation in markets and programs, but also determines which pathways, regions, and actors can credibly enter high-accountability settings, producing inclusion and exclusion at the same time.

The study is careful to state its limits. China’s blue carbon institutions remain in rapid development, and the purposive expert sample was designed to identify governance mechanisms and implementation frictions, not to represent all affected groups—particularly local communities, fishers, and aquaculture households. The research does not use longitudinal project-level monitoring data and therefore cannot directly assess the realized carbon performance, environmental integrity, durability, or distributive consequences of individual projects. Those caveats matter for readers hoping for proof that blue carbon projects deliver their promised climate benefits; this study is about institutional architecture, not measured sequestration outcomes.

Even within those limits, the conclusions travel beyond China. Ecological carbon sinks do not become credible climate assets simply because they can be quantified or traded; their governability depends on arrangements capable of sustaining verification, coordinating responsibilities across fragmented mandates, supporting durable implementation capacity, and allocating long-horizon risk. Blue carbon governance, the study concludes, is better understood as an iterative process in which imaginaries, technical rules, institutional devices, and practical constraints are continuously brought into alignment—standardisation first, methodology next, piloting thereafter, with each round of practice exposing choke points that travel back into rule-making. The broader challenge, on this reading, is not simply to bring nature into the market, but to build the institutional conditions under which claims about nature can remain credible, actionable, and accountable over time.

Subject of Research: The institutional and technical processes making marine blue carbon governable in China's climate policy

Article Title: Making blue carbon governable in China: standardisation, local experimentation and policy implications

Article References: Zhang, W. (2026). Making blue carbon governable in China: standardisation, local experimentation and policy implications. Regional Environmental Change, 26(4), Article 220. https://doi.org/10.1007/s10113-026-02711-x

Image Credits: AI Generated

DOI: 10.1007/s10113-026-02711-x

Keywords: blue carbon, China, carbon neutrality, mangroves, seagrass, carbon markets, MRV, standardisation, climate governance, marine carbon sinks, policy pilots, sociotechnical imaginaries