Diurnal and seasonal variations in carbon fluxes in bamboo forests during the growing season in Zhejiang province, China

Bamboo forest is an important forest type in subtropical China and is characterized by fast growth and high carbon sequestration capacity. However, the dynamics of carbon fluxes during the fast growing period of bamboo shoots and their correlation with environment factors are poorly understood. We measured carbon dioxide exchange and climate variables using open-path eddy covariance methods during the 2011 growing season in a Moso bamboo forest(MB, Phyllostchys edulis) and a Lei bamboo forest(LB, Phyllostachys violascens) in Zhejiang province,China. The bamboo forests were carbon sinks during the growing season. The minimum diurnal net ecosystem exchange(NEE) at MB and LB sites were-0.64 and-0.66 mg C m^(-2) s^(-1), respectively. The minimum monthly NEE, ecosystem respiration(RE), and gross ecosystem exchange(GEE) were-99.3 ± 4.03, 76.2 ±2.46, and^(-1)91.5 ± 4.98 g C m^(-2) month^(-1), respectively,at MB site, compared with-31.8 ± 3.44, 70.4 ± 1.41,and^(-1)57.9 ± 4.86 g C m^(-2) month^(-1), respectively, at LB site. Maximum RE was 92.1 ± 1.32 g C m^(-2) month^(-1) at MB site and 151.0 ± 2.38 g C m^(-2) month^(-1) at LB site.Key control factors varied by month during the growing season, but across the whole growing season, NEE and GEE at both sites showed similar trends in sensitivities to photosynthetic active radiation and vapor pressure deficit,and air temperature had the strongest correlation with RE at both sites. Carbon fluxes at LB site were more sensitive to soil water content compared to those at MB site. Both onyear(years when many new shoots are produced) and offyear(years when none or few new shoots are produced)should be studied in bamboo forests to better understand their role in global carbon cycling.

Key challenges and approaches to addressing barriers in forest carbon offset projects

Forest carbon offset(FCO)projects play an increasingly important role in mitigating climate change through market mechanisms in both compliance and voluntary markets.However,there are challenges and barriers to developing an FCO project,such as carbon leakage and cost-eff ectiveness.There have been few attempts to summarize and synthesize all types and aspects of existing challenges and possible solutions for FCO projects.This paper systematically reviews and discusses the current challenges involved in developing FCO projects,and then draws on the experience and lessons of existing projects to show how those challenges were addressed in world-leading voluntary carbon standards,namely the Verifi ed Carbon Standard,the American Carbon Registry,the Climate Action Reserve,and Plan Vivo.These voluntary markets have rich experience in FCO projects and are responsible for a signifi cant share of the market.From the 53 publications used in this analysis,three broad thematic categories of challenges emerged.These were related to methodology,socio-economic implications,and implementation.Methodological challenges,particularly additionality,permanence,and leakage,were the focus of 46%of the selected research papers,while socio-economic challenges,including transaction,social,and opportunity costs,were addressed by 35%.The remaining 19%of the research articles focused on implementational challenges related to monitoring,reporting,and verifi cation.Major voluntary standards adequately addressed most of the methodological and implementational barriers by adopting various approaches.However,the standards did not adequately address socio-economic issues,despite these being the second most frequently discussed theme in the papers analyzed.More research is clearly needed on the socio-economic challenges involved in the development of FCO projects.For the development of high-quality forestry carbon off set projects,there are many challenges and no simple,universal recipe for addressing them.However,it is crucial to build upon the current science and move forward with carbon projects which ensure eff ective,long-term carbon sinks and maximize benefi ts for biodiversity and people;this is particularly important with a growing public and private interest in this fi eld.

Grading of products utilizing bamboo as a substitute for plastic based on environmental effects

To achieve sustainable development goals,mitigate plastic pollution,and promote eco-friendly products,it is crucial to identify key products in the bamboo as a substitute for plastic(BSP)industry and assess their environmental effects.This study proposed a novel evaluation method for the environmental effect of bamboo as a substitute for plastic(EBSP).It focused on the contributions of BSP products in reducing plastic pollution and greenhouse gas emissions.We established a set of EBSP evaluation indicators and developed a grading model,evaluating 30 typical BSP products across six categories.The results showed that the EBSP evaluation model,based on the emission reduction rate of substitution(ERRS),substitution rate of material(SRM),and product renewal ratio(PRR),can accurately quantify the environmental benefits of BSP products.This model has successfully facilitated precise quantification of the EBSP and established a rational and effective grading system for BSP products.The results also demonstrated that the average EBSP ranking across the six categories of BSP products,in descending order,is:disposable bamboo products,bamboo household goods,bamboo packaging products,bamboo engineering materials,bamboo furniture products,and bamboo craft products.Specifically,disposable bamboo products scored an EBSP 1.96 times the overall average,indicating significant environmental benefits.The PRR emerged as a critical factor influencing EBSP.Among BSP products with the same lifespan,those with higher substitution emission reduction efficiency offered more pronounced environmental benefits.Ultimately,the BSP industry should strategically prioritize disposable bamboo products,such as bamboo toothbrushes,cutlery,and lunch boxes.These products should be the primary focus of policy support and central to efforts in product development,design innovation,and market promotion.

The phytolith carbon sequestration in terrestrial ecosystems:the underestimated potential of bamboo forest

Background Terrestrial ecosystems contain significant carbon storage,vital to the global carbon cycle and climate change.Alterations in human production activities and environmental factors affect the stability of carbon storage in soil.Carbon sequestration in plant phytoliths offers a sustainable method for long-term carbon stabilization.Carbon occluded in phytoliths(PhytOC)is a kind of carbon that can be stable and not decomposed for a long time,so it is crucial to conduct more in-depth research on it.Results We undertook a meta-analysis on PhytOC across global terrestrial ecosystems,analyzing 60 articles,encapsulating 534 observations.We observed notable differences in phytolith and PhytOC contents across various ecosystems.Bamboo forest ecosystems exhibited the highest vegetation phytolith and PhytOC content,while soil phytolith content was most prominent in bamboo forests and PhytOC content in croplands.Human activities,such as grassland grazing,had a lesser impact on soil PhytOC transport than actions like cutting and tillage in croplands and forests.Our study separated bamboo ecosystems,analyzing their PhytOC content and revealing an underestimation of their carbon sink capacity.Conclusions Notwithstanding our findings,phytoliths’intricate environmental interactions warrant further exploration,crucial for refining ecosystem management and accurately estimating PhytOC stocks.This deepened understanding lays the foundation for studying phytoliths and the carbon sink dynamics.