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Municipal sewage treatment plants yield lots of sewage sludge, which has complex composition, and improper disposal may cause environmental pollution problem. Therefore, proper sludge treatment is important to solve this problem. Traditional sludge disposal methods such as incineration and landfill have the drawbacks of high energy consumption and soil pollution problem. Anaerobic carbon fixation is a new sludge disposal method, which has good application prospect. This study adopted anaerobic carbon fixation to treat dreed sludge. The thermogravimetric analysis was carried out to assess the effects of process parameters (carbonization temperature and time) on the degree of anaerobic carbon fixation of dreed sludge. The influence of process parameters on the physicochemical properties, nutrient indicators, heavy metal content and seed germination index of sludge were investigated. Taking seed germination index as evaluation indicator, the optimum conditions were determined by extreme difference analyses of orthogonal tests. The results indicated that high carbonization temperature and long carbonization time were crucial to ensure that anaerobic carbon fixation of sludge fully competed. Process parameters had significant effects on the properties of sludge. Various performance indicators of sludge treated by anaerobic carbon fixation could meet the standard of municipal sewage treatment plant sludge disposal for landscaping purpose (GB/T 23486--2009), so the treated sludge could be used as landscaping substrate. The optimum carbonization temperature and time were determined as 600 °C and 1.5 h, respectively. In this condition, sludge anaerobic carbon fixation fully competed and the content of toxic and harmful substances such as soluble salts and water-soluble heavy metals in treated sludge were low, which was conductive to seed germination. Seed germination index reached 138. 79%, far higher than the national production quality standard (70%). As a result, anaerobic carbon fixation treatment and effective process parameters adjustment open up new possibility for sludge resource utilization. [ABSTRACT FROM AUTHOR]

Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of New Building Materials / Xinxing Jianzhu Cailiao is the property of New Building Materials Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

CO2 is one of the main greenhouse gases. A large amount of CO2 is released into the atmosphere through industrial production and human activities, leading to a significant increase in global CO2 concentration. This has resulted in the increasing global temperatures, climate warming, and frequent occurrences of extreme weather events, posing a threat to global human security. In order to mitigate the increase of CO2 and address global warming, countries around the world have set carbon peak targets and are committed to carbon capture and utilization. Marine Isochrysis galbana characterizes of a fast growth rate and high carbon-fixing efficiency; moreover, biological carbon sequestration mediated with Isochrysis strain and wastewater synthesized various high-value biologically active substances such as protein, polyunsaturated fatty acids; which is regarded to be a promising way of fixing CO2 . In this review, we firstly summarize the prevalent CO2 capture technologies and compares their advantages and disadvantages. Furthermore, we elaborate the carbon metabolism mechanism of Isochrysis strain for the carbon fixing process, and explain the relationship among the Calvin cycle, TCA cycle, and the metabolism of various biologically active substances during photosynthetic carbon fixation. Based on the photosynthetic carbon-fixing mechanism of Isochrysis strain, we propose some methods about cultivation conditions, photobioreactors and modified microalgal cells by genetic engineering and synthetic biology to improve carbonfixing efficiency for Isochrysis strain. Lastly, we illustrate the correlation between carbon fixation of Isochrysis strain and the synthesis of bioactive components, offering essential details for high valued Isochrysis-derived bioproducts by deep processes. This review will provide essential perspectives to address carbon neutrality by microalgal carbon sequestration and exploit high-value microalgal bioproducts by Isochrysis strain. [ABSTRACT FROM AUTHOR]

[Objective] The synthesis pattern of tea tree chlorophyll by synergistic effect of soil pH and magnesium ions was explored to pro- vide theoretical basis for the cultivation of tea tree and breeding of new variety. (Method) Taking Fuding Dabaicha as the study object, the plant tissue enzyme activity kits were used to determine the synergistic effects of the soil with different pH pH 4 (P1) and pH 5 (P2)] and different magnesium ion concentrations [0 mg/L (To, CK), 50 mg/L (T1), 100 mg/L (T2) and 150 mg/L (T3)] on the key enzymes of chlorophyll synthesis in tea tree, including magnesium chelatase, uroporphyrinogen III synthase and 5-amino ketoglutarate dehydratase. The high-throughput technology was used for transcriptomic sequencing of the leaf slices tissue of Fuding Dabaicha with different treatments, and then the synergistic effect of soil pH and magnesium ion on the synthesis of chlorophyll in tea tree were studied. (Result) The soil pH and magnesium ions had different synergistic effects on the key enzymes of chlorophyll synthesis in tea tree (magnesium chelatase, uroporphyrinogen III synthase and 5-amino ketoglutarate dehydratase). The activities of magnesium chelatase, uroporphyrinogen III synthase and 5-amino ketoglutarate dehydratase treated with P2T, were the highest with 492.41, 336.28 and 132.24 U/L, respectively. The analysis of GO and KEGG functional enrichment showed that the key regulatory genes in the development of Fuding Dabaicha leaves were mainly involved in the processes of carbohydrate metabolism and polysaccharide metabolism. The differentially expressed genes were mainly enriched in starch and sucrose metabolism, stilbenes and other pathways. The analysis of KEGG metabolic pathway of photosynthesis of carbon fixation pathway showed that P2T, treatment significantly improved the carbon fixation pathway of tea tree, and had a promotional effect on both photosynthesis and sugar accumulation. [Conclusion] P2 T1 treatment (the synergistic effects of pH 5 and 50 mg/L magnesium ion) of tea tree has the best effect on chlorophyll synthesis, which is beneficial to the synthesis and accumulation of materials, and is advantageous to the quality and yield of tea tree. [ABSTRACT FROM AUTHOR]

Presently, ocean acidification (OA) is escalating at an unprecedented pace, posing a considerable threat to the chemical equilibrium of seawater. This acceleration has the potential to disrupt the marine ecological environment significantly, affecting various organisms. Among these, algae, the primary producers in the ocean, contribute 95% of productivity and play a vital role in material and energy cycling. The increasing acidity in the ocean could alter algae productivity, subsequently impacting material and energy transfer through the marine food web. Such changes may initiate a cascade effect in the food chain, leading to irreversible damage to the entire marine ecosystem. Additionally, algae's heightened sensitivity to environmental changes makes them valuable as "indicator organisms" for monitoring water quality. Therefore, assessing the ecological impact of ocean acidification on algae is crucial for ecological research. This review aims to outline the effects of ocean acidification on the physiological and biochemical processes of algae over recent years. This includes aspects such as photosynthesis, inorganic carbon fixation, growth, calcification, reproduction, as well as metabolic components and microstructure. The review also explores how ocean acidification influences the molecular regulation mechanisms of algae, considering its combined effects with environmental factors and marine pollutants. Furthermore, the article analyzes the limitations of current algae research on ocean acidification and proposes solutions and strategies to address this pressing issue. [ABSTRACT FROM AUTHOR]

Calcium carbide slag was used to replace part of cement in this study to prepare a new type of cementing material, and the influence of cementing materials with different contents of calcium carbide slag on the basic performance and carbon fixation performance of 600 kg/m³ grade foam-reinforced concrete were studied. The results show that calcium carbide slag can increase the porosity of foamed concrete, increase the compressive strength at 28 d and then decrease, and improve the thermal insulation performance. When calcium carbide slag replaces 10% cement, the dry density of foam-reinforced concrete is 595 kg/m³, and the compressive strength of foam-reinforced concrete increases 4.2% to 5.0 MPa at 28 d. When calcium carbide slag replaces 50% cement, the thermal conductivity of foam concrete decreases by 17.1% to 1.131 W⋅m-1⋅K-1. The addition of calcium carbide slag is beneficial to improve the shrinkage of foamed concrete. When the content of calcium carbide slag increases, the shrinkage of foamed concrete decreases first and then expands. Carbonization curing can not only solidify and sequestrate CO2, but also improve the mechanical properties and thermal insulation properties of foamed concrete. The higher the content of calcium carbide slag is, the stronger the carbon fixation ability of foam concrete is. When the content of calcium carbide slag is 50%, the CO2 capture amount reaches 46.02 wt%. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The material flow analysis (MFA) method is widely used in the fields of resource management, environmental governance, and sustainable development evaluation, but the progress of its international research and the paths to support carbon neutrality are still unclear. Therefore, following the logic of ' sorting-integration - expansion,' this study first analyzed 2 148 documents included in the core database of Web of Science from 2000 to 2022 by using CiteSpace bibliometric tools, captured the key knowledge base and topic evolution of the international MFA research, and conducted a detailed review and comprehensive analysis of the MFA frontier application research. Second, by integrating the current status of international MFA research and the paths to carbon neutrality, this study constructed an integrated MFA research framework towards carbon neutrality. Finally, this paper summarized the support paths of MFA application research for the four important carbon reduction sectors and proposed current research deficiencies and future development directions. The main findings include: (J) The key studies in the fields of ' resource management,' ' environmental accounting,' and ' indicators ' could serve as a methodological and theoretical basis for MFA to perform its management, accounting, and evaluation functions. © With the support of the basic research topics of 'industrial ecology,' 'material flow analysis,' and 'material flow management, ' the application research topics of MFA had gradually evolved from the outdated topics of ' nitrogen,' ' Tarragona province,' ' heavy metals,' and ' alloying elements' to the frontier topics of ' municipal solid wastes,' ' iron,' ' circular economy,' ' exposure,' and ' renewable energy,' and the integrated application of MFA with the methodologies of scenario analysis, life-cycle assessment, and input-output modeling had become a mainstream trend. © The integrated MFA research framework towards carbon neutrality consisted of three modules, i.e., theoretical and methodological basis, application research paradigm, and supporting pathway for carbon neutrality, of which the structure of the application research paradigm reflected the core functions of the MFA, i.e., accounting material stocks and flows, assessing material demand and recycling potential, and developing the material management system. The elements of the application research paradigm covered the metabolic object, spatial scale, application triggers, main content, and application purpose of MFA research. ® The studies of MFA application supported the four important carbon reduction sectors in heterogeneous ways, and their relevance to the goal of achieving carbon neutrality needed to be further improved. In future research, MFA can be applied to account for the resource demand and waste generation of specific zero-carbon technologies in the energy production sector, to assess the resource and environmental impacts of end-use electrification, efficiency, and cleaner technologies in the energy consumption sector, to measure the environmental exposures and economic feasibility of the technologies for decarbonization and solid-waste utilization in the industrial and commercial sectors, and to evaluate the metabolic efficiency of nutrients and the performance of biological carbon fixation in the agriculture and forestry sectors. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Molecular Science is the property of Journal of Molecular Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of Botanical Research is the property of Bulletin of Botanical Research Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To investigate the daily variation of net photosynthetic rate of Carallia brachiata (Lour.) Merr. in different seasons and its relationship with physiological ecological factors, the daily variation of net photosynthetic rate and the daily variation of physiological and ecological factors were measured by LCi-SD portable photosynthesizer in spring (April), summer (July), autumn (October) and winter (January). The interactions between the net photosynthetic rate and physiological and ecological factors were analyzed by biostatistical methods (simple correlation analysis, partial correlation analysis and multiple linear regression analysis). The results showed that: (1) The net photosynthetic rate (Pn) showed a "bimodal" curve trend in July, with the phenomenon of "photosynthetic siesta". There was no "photosynthetic siesta" in January, April and October. (2) The daily changes of net photosynthetic rate (Pn) in C. brachiata were affected by physiological ecological factors differently in different seasons. By simple and partial correlation analysis, the main ecological factors in spring were air CO2 concentration (Ca); physiological factors were intercellular CO2 concentration (Ci) and stomatal conductance (Gs). In summer, the main ecological factors were effective photosynthetic radiation (PAR) and leaf temperature (Ti), and the physiological factors were Gs, transpiration rate (Tr) and Ci. In autumn, the main physiological factors were Tr. In winter, the main physiological factors were Tr and Gs. (3) Further multivariate linear analysis showed that Tr was the main factor influencing net photosynthetic rate in autumn and winter. Ci was the main factor affecting net photosynthetic rate in spring, and Gs and Ci were the main factors affecting net photosynthetic rate in summer. [ABSTRACT FROM AUTHOR]

The study of dark carbon fixation in estuarine wetlands is of great scientific significance for the comprehensive understanding and scientific assessment of the carbon sink potential of estuarine wetlands. Taking Chongming Dongtan as a typical study area, the effects of different wetland vegetation distributions on sediment dark carbon fixation and its key environmental control factors were studied using 14C isotope labeling technology combined with molecular biology research methods. The results showed that: the annual mean values of sediment dark carbon fixation rates in mudflat, Phragmites australis, and Spartina alterniflora wetlands were (1.27±0.66), (0.88±0.40), (1.37±0.63) mmol/(m² · d) C, respectively; there were significant seasonal differences in sediment dark carbon fixation in estuarine wetlands, in which the dark carbon fixation rates increased significantly in summer, but were inhibited by extremely high temperatures; the dark carbon fixation in sediments was promoted by Spartina alterniflora, while that in the Phragmites australis area was reduced relative to the mudflat; different vegetation influenced the dark carbon fixation in the sediment by regulating the NH4+, Fe3+, S2- and the abundance of functional genes (cbbL and cbbM). The results provide a theoretical reference to accurately assess the carbon sink potential and the influence mechanisms of the estuarine wetlands. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Minerals & Processing / Huagong Kuangwu yu Jiagong is the property of Industrial Minerals & Processing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

CO2 mineralization curing is considered an effective approach to mitigate the impact of the construction industry on global climate change by reacting CO2 with cement-based materials (CBM) (e. g. cement clinker, namely tricalcium silicate, β-dicalcium silicate, tricalcium aluminate and its hydration products, namely calcium hydroxide, amorphous calcium silicate hydrates, hydrated aluminate and sulfate phases) to form calcium carbonate mainly composed of calcite and amorphous silica gel with high degree of polymerization, realizing the storage and utilization of CO2. Attributed to the good stability, filling effect and nucleation effect of the resultant products, the mechanical properties and durability of CBM are effectively improved while better performance is anticipated in a relatively short time compared with other curing technologies. In this paper, the reaction mechanisms and latest research progress of CO2 mineral carbonation-cured CBM are reviewed. The effect of influencing factors, such as pre-condition, relative humidity, water binder ratio, CO2 concentration, curing pressure and temperature on the post-mineralization properties, carbon fixation rate and mineralization degree are evaluated. Finally, based on the current research status and existing problems, suggestions and recommendations for a wider application of CO2 mineralization technology in the future are also provided. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Wildland Fire Science is the property of Journal of Wildland Fire Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, the Water Yield module of InVEST 3.8, the soil erosion equation model (RUSLE) and the soil wind erosion model equation (RWEQ) were used to estimate the four ecosystem service functions of Yixing, including water conservation, soil conservation, wind prevention and sand fixation, carbon fixation and oxygen release, respectively. Then, 10 resistance factors such as elevation and slope were selected to evaluate the resistance level of ecological expansion in Yixing. Finally, the minimum cumulative resistance model (MCR) based on the source sink theory was used to simulate the ecological security pattern of Yixing at county scale. The results showed that: (1) the range of water conservation capacity was 213 mm-1594 mm, the range of soil conservation capacity was 11562.28 t·hm–2-268034.28 t·hm–2, the range of wind break and sand fixation capacity was 0.54 kg·m–2-11.6 kg·m–2 and the range of oxygen release capacity of was 502.82 t·hm–2-1321.83 t·hm–2. The ecological sources were mainly distributed in the Tianmu Mountain in the south, Taihui Lake in the East and Yinghu Lake in the north, Dongwan Lake, Xiwan Lake and Daxihe River in the middle. (2) The resistance level of ecological expansion from low to high accounted for 53.13%, 23.50%, 15.07% and 8.30% of the total area of Yixing City, respectively. The low resistance level area was relatively concentrated in the Eastern Taihu Lake area, the southern Tianmu Mountain area, and the eastern and Xiwan wetland areas in the middle. The lower resistance level was mainly distributed along the low resistance level zone. The middle and high resistance level areas were mainly distributed in agricultural production and residential areas where human activities were relatively intense. (3) The ecological security pattern of “one vein, three lakes, two vertical, five horizontal, and thirteen cores” was constructed in Yixing. Compared with the planned ecological redline, the additional ecological corridors and ecological nodes were beneficial to connect the broken habitats and form a complete ecological network pattern. [ABSTRACT FROM AUTHOR]

Light use efficiency (LUE) is a key parameter connecting light absorption and carbon fixation and understanding the relationship between fluorescence and photosynthesis. Based on the absorbed energy dissipation pathways, LUE can be divided into light use efficiency of photosynthetic (LUEp) and light use efficiency of fluorescence (LUEf). The relationship between LUEp and LUEf of poplar and cork oak and the differences between species were explored in this study, to better understand the mechanism links between solar-induced chlorophyll fluorescence (SIF) and gross primary productivity (GPP) in deciduous broadleaf forests. In this study, the poplar (Populus alba x Populus gllandulosa) and cork oak (Quercus variabilis BI.) seedlings were used as the objects to measure the divergences in SIF and net photosynthetic rate (Pn) under the same soil moisture and nutrient conditions, to explore the responses of LUEp/LUEf to photosynthetically active radiation (PAR). The results showed that, (1) SIF was driven by incident PAR, SIF and PAR were significantly positively correlated. The coefficient of determination (R²) of poplar and cork oak were 0.965 and 0.973, respectively, and LUEf was higher in poplar. Pn gradually increased with increasing PAR. The light saturation point (LSP) of poplar was significantly higher than that of cork oak, which were 998.59 and 674 μmolCO2·m-2·s-1, respectively. (2) Pn first increased with the increasing SIF, and then the Pn of poplar was gradually saturated, while that of cork oak continued to slowly increase. (3) LUEp and LUEf showed significant negative linear correlation, and LUEp/LUEf decreased exponentially with increasing PAR, there was no significant difference in the change pattern and amplitude between tree species. During the daytime, with the increase of PAR, LUEf changed slightly, while LUEp decreased significantly, and the proportion of light energy allocation to carbon assimilation decreased. Therefore, Pn saturated under high light intensity, SIF and GPP showed exponential correlation in intraday scale, and the exponential relationship was consistent across tree species. [ABSTRACT FROM AUTHOR]

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Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The reasonable pyrolysis temperature of sludge was determined to make the biochar have good Cu(II) adsorption capacity and maximum carbon sequestration potential. Biochar was prepared from the sludge of wastewater treatment plant in Chongqing at different pyrolysis temperatures, and its physical properties was characterized by X-ray diffraction, X-ray fluorescence and Fourier transform infrared spectroscopy, the effect of pyrolysis temperature on the adsorption of Cu(II) was evaluated by the adsorption of biochar; and the carbon sequestration potential of biochar at different pyrolysis temperatures was evaluated by carbon retention (YC), fixed carbon yield (YFC) and thermal stability. The results showed that the adsorption capacity difference of biochar for Cu(II) was little when the pyrolysis temperature was lower than 300 ℃. However, with the increase of pyrolysis temperature above 300 ℃, the adsorption capacity of Cu(II) on biochar decreased. The ash in biochar is mainly SiO2, it did not contribute to the adsorption of Cu(II) on biochar, the adsorption capacity of biochar for Cu(II) was restricted by oxygen-containing functional groups and specific surface area. In addition, YFC could comprehensively measure the carbon sequestration effect of biochar than YC or thermal stability alone. The YFC of 300 ℃ biochar was the largest and the carbon fixation effect was the best. Considering the adsorption capacity of Cu(II) and carbon sequestration potential, it was suggested that the pyrolysis temperature of biochar prepared from municipal sludge in mountainous cities should be set at 300 ℃. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to investigate the correlation between photosynthetic characteristics and physiological-ecological factors as well as the changes of photosystem PSII activity in Rhodomyrtus tomentosa under different seasons.【Method】In the experiment, 3-year-old R. tomentosa was used as the test material, and the measurement studies were conducted in spring（April）, summer（July）, autumn（October） and winter（January） using LCi-SD portable photosynthesizer and hand-held chlorophyll fluorescent fluoropen（FP110PAR-FluorPen）.【Result】‘Midday depression of photosynthesis’ in net photosynthetic rate（Pn） in both spring and winter was caused by stomatal limitation, and the ‘midday depression of photosynthesis’ in Pn in summer was caused by non-stomatal limitation. ‘Midday depression of photosynthesis’ in summer was caused by non-stomatal limitation. Stomatal conductance（Gs）, relative humidity（HR） and intercellular CO2 concentration（Ci） were the main factors affecting Pn in spring, while effective photosynthetic radiation（PAR） was the main factor affecting Pn in summer. Transpiration rate（Tr）, Gs and Ci were the main factors affecting Pn in autumn, while Tr and air CO2 concentration（Ca） were the main factors affecting Pn in winter. The PSII activity（Fv/Fm） of the photosystem was the highest in summer and the lowest in winter, and the energy captured by R. tomentosa antenna pigments（ABS/RC） was the highest in spring. Quantum yield（QY） was the highest in summer and the lowest in autumn under photostasis. The QY under darkness was maximum in summer, minimum in spring, and the highest in autumn for NPQ（non-chemical quenching）. The R. tomentosa QY was the greatest in spring and winter at a light intensity of 100 μmol/（m²·s）, and decreased with increasing light intensity in summer and autumn. The Fv/Fm of R. tomentosa photosystem PSII showed an increasing trend with the increase of light intensity in different seasons.【Conclusion】Environmental changes in different seasons can lead to the phenomenon of ‘midday depression of photosynthesis’ of stomatal limitation and non-stomatal limitation in R. tomentosa. The effect of physiological ecological factors on photosynthesis was different in different seasons. R. tomentosa’s photosystem PSII activity（Fv/Fm） was summer>autumn>spring>winter, while its ABS/RC was spring>autumn>summer>winter. The QY under photostasis was summer>winter>spring>autumn, and the maximum QY was summer>winter>autumn>spring. [ABSTRACT FROM AUTHOR]

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Net Primary Productivity (NPP) of vegetation is considered one of the main indicators for the carbon fixation capacity of ecosystems in the carbon cycle, particularly for the adaptability of ecosystems to climate change. Among them, the typical phenological factors are the key components of the ecosystem functions in many biological processes, including the Start of the Growing Season (SOS), End of the Growing Season (EOS), and Length of the Growing Season (LOS). However, it is still lacking in the relative importance of phenological and climatic factors to the NPP. The contribution of phenological factors (SOS, EOS, and LOS) to the interannual change of NPP has not been well quantified, due to the complex ecosystem. Therefore, this study aims to extract the phenological information of vegetation using a Cardiovascular-Ames-Stanford Approach (CASA) model, in order to examine the characteristics of spatial and temporal changes of NPP. The Normalized Vegetation Index (NDVI) was used from the MODIS data in Beijing from 2001 to 2020. The interaction between meteorological factors, phenological changes, and NPP was then explored using linear regression, trend analysis, and structural equation modeling. The results show that the SOS was gradually advanced by 0.57 each year on average from 2001 to 2020 over more than 70% of the regions, whereas, the EOS was gradually postponed by an average of 0.51 days per year over more than 90% of the regions. The NPP vegetation increased significantly from 2001 to 2020 (P < 0.05), where the growth rate was greater in the last 10 years than that in the first 10 years. The average annual NPP value was greater in the northern region than that in the southern. There was a strong correlation between the phenological factors (SOS, and LOS) and NPP (P<0.05). The pixel-by-pixel analysis also found that the SOS, LOS, and NPP were significantly correlated in the areas with more than 75% vegetation coverage. The NPP was also significantly affected by the advance of SOS and extension of LOS (P<0.05). The NPP increased by 3.74 g/m² for every single day advance of SOS, while by 2.65 g/m² for every single day extension of LOS. There was no significant effect of the EOS delay in autumn on the NPP. A coupling effect of phenology and climatic factors varied with the season. There was a greater indirect effect of climate through changing phenology (SOS and EOS) on the NPP in spring and autumn, compared with the direct. By contrast, the NPP was more directly affected by climatic factors, temperature, and rainfall in summer. In conclusion, the spring phenological change was an important driving factor for the interannual variation in the NPP. Furthermore, the annual NPP increased to the phenological advance. The findings can also provide an important supplement to determine the vegetation productivity response to the climate change in urban areas. [ABSTRACT FROM AUTHOR]

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Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of South China Normal University (Natural Science Edition) / Huanan Shifan Daxue Xuebao (Ziran Kexue Ban) is the property of Journal of South China Normal University (Natural Science Edition) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective]The purpose of this stndy was to identify the distribution characteristics of nutrient elements in the soil of Yuanmou county, to grasp the nutrient problem of the soil in this area, to come up with reasonable suggestions for land use and improvement, to improve the technical level of land management and design in the area, to use the land scientifically and promote the healthy development of the agricultural economy. [ Method] A total of 2368 topsoil samples were collected at a density of 1. 2 s amples/km² throughout Yuanmou county, using the method combining traditional geochemistry, geology, and ecology, which were combined into 513 analysis samples, and 510 components were remained after screening and processing. The characteristic parameters of the data were analyzed using Excel, SPSS, etc., and the mathematical models of abnormal el ements were established. Finally, with reference to the rel evant specifications, GeolPAS and ArcGIS were used to create the maps and integrate the results. [Result] The distribution of organic carbon (Corg), nitrogen (N), phosphorus (P), potassium oxide (K2 0), magnesium oxide (MgO), manganese (Mn), molybdenum (Mo), zinc (Zn), total iron (TFe2O3), copper (Cu), and boron (B) in the topsoil of Yuanmou county was balanced. Among them, the main element Corg and N content were low overall, and their correlation coefficient was significantly positive (R² ~ 0 . 66). The balance of sulfur (S) and cal cium oxide (CaO) was lower than other el ements, which showed abnormalities, and there were no abnormalities in trace el ements. The results of comprehensive grade evaluation of nutrient elements showed that the rich area were mainly distributed in the northwest of Jiangyi town, the line of Wumao villageJiangbian town-Huangguayuan town-Pingtian towns, Laocheng town and the southeast of Y angjie town, which was consistent with the distribution of the main agricultural areas in Yuanmou county. [ Conclusion] There were two causes of the low contents of Corg and N were mainly two: (i) the sandy content of the soil was generally high, and its ability of water and fertilizer conservation was not strong; (ii) The biological carbon and N fixation capacity was weak in most of the areas with low vegetation shade, except for the concentrated area of cultivated land. The CaO ratio of cultivated land in the study area was relatively high, and the CaO content in the soil was low in equilibrium affected by human, which did not caused soil pollution and soil deterioration. The high level of S deficiency was related to the lack of organic sulfur in the soil due to the fragile ecosystem in the dry hot valley. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To explore the more efficient regulation mechanism of lipid accumulation in Desmodesmus sp. under mixotrophic condition, Desmodesmus sp. were cultivated unde autotrophic and mixotrophic conditions, and differences of lipid accumulation of Desmodesmus sp. under two cultivation conditions were compared using transcriptome sequencing. The results showed that the mixotrophic group had 1081 up-regulated genes, 575 down-regulated genes, and 23 331 non-significantly differentially expressed genes. The enrichment of the differential gene GO term was mainly in the molecular function, biological process and cell components of photosynthesis, such as thylakoid, photosystem I, chlorophyll binding, photosynthetic electron transport, light response and dark response etc. The enrichment of KEGG pathway was mainly characterized as photosynthesis, followed by fatty acid elongation, protein processing in the endoplasmic reticulum, and starch and sucrose synthesis. Under mixotrophic condition, reduced PS II's demand for light energy was reduced, but photosynthetic electron transport was enhanced, and more ATP and NADPH were produced for carbon fixation in photosynthesis and other metabolic activities of cells. The enhancement of lipid accumulation was mainly due to the enhancement of glycolytic pathway, which produced more acetyl- CoA for fatty acid production and promoting fatty acids production. [ABSTRACT FROM AUTHOR]

In order to realize the real-time, continuous and accurate detection of the plant’s CO2 absorption rate in the measurement of plant carbon fixation, in this paper, based on quartz enhanced photoacoustic spectroscopy（QEPAS）, the absorption wavelength of 1 580.039 5 nm in infrared region was selected as the spectrum line to be mearsued, and a plant carbon sequestration measurement and detection system was built, the lower limit of the gas volume fraction detection of the system was 65×10-6. Under the condition of consistent light intensity, temperature and plant growth, the CO2 absorption rate of the Spathiphyllum kochii, Ficus elastica, Chlorophytum comosum and Epipremnum aureum was detected for many times within one hour. The relative error between the daily carbon sequestration per unit leaf area and the reference value in the literature was less than 7 %, which proved that the QEPAS-based plant carbon sequestration detection system could detect the CO2 absorption rate of plants in real time and continuously, and estimate the carbon sink capacity of plants. [ABSTRACT FROM AUTHOR]

n order to understand characteristics and significance of carbon(C), nitrogen(N), phosphorus(P)and stable carbon isotope composition(δ13C)in plant leaves of three typical aquatic plants under different growth environments, three life forms of aquatic plants including emerging plant(Phragmites australis), emersion plant(Eichhornia crassipes) and submerged plant(Ceratophyllum demersumin) of the Huixian karst wetland were selected as study objects. The differences of carbon isotope compositions of interspecies and different habitat conditions were studied, and the percentage of HCO-3 uptaken from water by aquatic photosynthesis was also estimated using the double-meta model. The results were as follows:(1)The foliar δ13C of three diffirent plant life forms ranged from -28.47‰～-21.69‰ with an average of -24.83‰. There were significant differences among species, and the sequence of relative value was Ceratophyllum demersum>Eichhornia crassipes>Phragmites australis, and among the three types of plants,Phragmites australis and Ceratophyllum demersum show the lowest and highest δ13 C, respectively.(2)For three types of halophytes,δ13C showed significantly positive correlations with foliar C, N and P. The δ13C was also positively correlated with the contents of organic matter, available nitrogen, total nitrogen, available phosphorus and total phosphorus of sediment. All types of halophytes showed a negative correlation among δ13C, C/N, N/P and C/P.(3)The foliar N/P ratio of halophytes was 10.34, indicating a co-limitation by N and P for halophyte growth in the Huixian karst wetland.(4)These results suggested that three halophytes were adapted to environment through a high water use efficiency at the expense of decreased nitrogen use efficiency, and might improve C sequestration by increasing phosphorus use efficiency in the habitat of low water availability.(5)The value of HCO-3 carbon sequestration by photosynhesis was 159.60 t·a-1·km-2 for Phragmites australis, 10.80 t·a-1·km-2 for Eichhornia crassipes, 9.24 t·a-1·km-2 for Ceratophyllum demersum, with a mean value of 59.88 t·a-1·km-2. Different plant life forms, pathways of carbon fixation in photosynthesis and micro-environment were the important factors on affecting plant foliar δ13C in the Huixian karst wetland. [ABSTRACT FROM AUTHOR]

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Mycosystema is the property of Mycosystema Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As a special ecological and geographical region, the Tibetan Plateau provides various ecosystem services for the surrounding areas. Does the ecosystem service perceive differently from the public who have regional characteristic respectively? Meanwhile, would the regional difference influence the valuation of the Tibetan Plateau and ecological management measures? Based on 13254 questionnaires from 27 cities in China, this paper aims to value the ecosystem service and the drivers of public willingness to pay, and probe into the spatial heterogeneity in the above- mentioned verdict. The results show that: (1) The sorts of average maximum willing payment are: Northeast and North regions (1185.7 yuan/year) > Southeast coastal region (1021.1 yuan/year) > Northwest region (1012.3 yuan/year) > Central region (957.1 yuan/year) > Southwest region (894.7 yuan/year). (2) The allocation proportion sequence of ecosystem services is sorted as water conservation > carbon fixation > soil retention > biodiversity conservation > pollution decomposition > aesthetic existence. The allocation proportion of payment has no spatial heterogeneity in water conservation and aesthetic. The people in Northwest and Southwest regions are willing to pay more in soil retention, while those in Southeast coastal, Southwest and Central regions are willing to pay more compared with North region in pollution decomposition. It is difficult to grasp the spatial heterogeneity in carbon fixation and biodiversity conservation. (3) The drivers of public willingness to pay are ordered as ecosystem management attitudes > subjective indicators > objective indicators. (4) The types of ecosystem services and the level of urban development are the dominant factors for the regional differences of payment amount. The spatial difference has no influence on water conservation and aesthetic existence, and the objective indicators of the first-tier cities link less tighter to the payments than others do. Spatial distance only affected the correlation between biodiversity conservation and per capita monthly income. The findings can enhance the publicity of ecosystem management in the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Southern Agriculture is the property of Journal of Southern Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As a typical land consolidation type, there is great significance for mastering regularity of carbon effect in land reclamation systematically by analyzing carbon effect mechanisms and calculation methods under the new situation of strengthening ecological civilization construction and "carbon fixation & emission reduction". Following the principle of system theory and starting from the time logic of land reclamation project cycles, this study illustrated the carbon effect mechanism from three aspects, including land structure, construction implementation, and project management. Meanwhile, the carbon emission coefficient method and comprehensive comparative analysis were used to calculate carbon emission for eight projects in Guangxi. The results illustrated that the carbon effect mechanism for temporary land reclamation based on project time logic included:Carbon effect Ⅰ for land structure and for construction implementation, carbon effect Ⅱ for construction implementation and for land structure, and carbon management effect. During the project cycle, the carbon effects of each project was -24.41~78.74 t (negative for carbon emissions and positive for carbon sequestration), respectively, including the carbon effects caused by land structure change at 3.66~82.50 t, carbon effects from construction implementation at -33.57~-0.78 t, and carbon effects from later management at -13.48~0.01 t. The main influencing factors of the carbon effect in land structure were that the root canopy has become smaller after reclamation and its carbon fixation capability had been reduced accordingly. Moreover, the main influencing factor of the carbon effect in construction implementation was material consumption, especially cement. The main influencing factors of carbon management effects were soil fertilization for three years after reclamation and the use of large quantities of chemical fertilizers, which had increased carbon emissions. The implementation of stripping and using plow layer soil, emphasizing the carbon sequestration capacity of woodland after reclamation, and reducing the consumption of industrial materials will be important measures for low-carbon reclamation of temporary land, which occupies cultivated land resources and occupies woodland resources and has a damage degree of moderate or above. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Biochar can repair soil, replace fossil fuels, and adsorb environmental pollutants. Biochar helps to reduce greenhouse gas emissions and prevent environmental pollution. Its application value is very large and its use range is wide. At present, there are problems such as large differences in quality of straw-based biochar products, inconsistencies in characteristics and test methods. This paper systematically studied the quality requirements of biochar at home and abroad. The research put forward the biochar evaluation index system of fertilizer application, energy carbon, activated carbon and other application directions. Focusing on straw biochar, the study analyzed the meanings and influencing factors of physical, chemical, thermochemical, surface chemistry and toxic pollutants. The results showed that the content of C element in straw biochar was generally higher than 40%, and the pH value was alkaline, generally 7.0-10.3. Straw biochar contained a certain amount of nutrients and could be used as a fertilizer supplement, but it was necessary to prevent the risk of heavy metals exceeding the standard. The straw-like biochar had a calorific value of 20-30 MJ/kg, a fixed carbon content of 40%-70%, and a volatile content of 15%-25%, which was close to the medium and low volatile bituminous coal, could be used as an energy carbon application. The straw biochar had high alkali metal and chlorine content, low ash melting point, so it needed to prevent slagging and corrosion problems. The specific surface area of straw biochar was <500m2/g, the pore size distribution was concentrated near mesopores, and the CEC value was <50 cmol/kg. The most important functional group on the surface of biochar was oxygen-containing functional group, and the number of basic functional groups was average, which was greater than the number of acidic functional groups. Biochar had a large specific surface area, a rich surface pore diameter, and a certain adsorption property, which could be used for activated carbon. The contents of toxic pollutants PAHs, PCBs and PCDD/Fs in biochar were below the limits. Biochar had a stable structure, which was conducive to carbon fixation, and it had rich surface pore structure and strong adsorption, and it can prevent environmental pollution and reduce greenhouse gas emissions. The research put forward the biochar quality evaluation index and index range requirements for fertilizer application, energy carbon, activated carbon and other application directions, and recommended the measurement standards of the corresponding indicators. The number of indicators was: fertilizer carbon included 21 items, energy carbon included 19 items, and activated carbon included 7 items. It was recommended to develop biochar quality evaluation and grading standards as soon as possible to provide technical support for promoting the multi-value and high value utilization of biochar products, and further accelerating the industrial application of biochar. [ABSTRACT FROM AUTHOR]

The technology of carbon capture, utilization, and storage (CCUS) is an important component of carbon neutral technology systems. To confirm the carbon storage potential of CO 2 foamed concrete (CFC), this study addressed the principle of carbon storage in CFC materials. It is apparent that carbon storage of CFC materials includes carbon fixation in concrete skeletons and carbon storage in CFC bubbles. The carbon fixation of CFC skeletons is realized by CO 2 mineralization. As the concrete skeleton in CFC is in the CO 2 atmosphere, the carbonation of CFC materials or CO 2 mineralization is more complete. Research shows that the carbonation rate of CFC materials can reach almost 30% after acidification, foaming with high CO 2 pressure and curing in the atmosphere. The carbonation rate is higher than the rate in concrete curing with CO 2 . A mathematical model was established to calculate carbon fixation capacity in CFC materials, and the carbon fixation and storage capacity in CFC material were estimated. The results showed that more than 99% carbon storage of CFC was realized by the chemical carbonization of the concrete skeleton. Comparatively, the potential of carbon storage in the bubble of CFC was small. In this study, carbon storage capacity was divided into three categories, i.e., theoretical maximum capacity, relative reliable capacity, and expected capacity or potential. The carbonation rate for theoretical maximum capacity was 100%, when all the concrete was considered to be carbonated. As the carbonation rate of concrete during the whole life cycle is approximately 55% all over the world, 50% was set as the carbonation rate for relative reliable capacity calculation. If at high temperatures, CO 2 curing with high pressure or accessory ingredients applied to silicate concrete can improve carbonation rate to be over 80%, when the carbon storage capacity is considered to be expected capacity or potential. In 2017-2021, the theoretical maximum capacity of carbon storage was 3.623×10 9 t CO 2 in China, with 7.25×10 8 t·a -1 . The relative reliable capacity was 3.75×10 8 t·a -1 , and the expected capacity was 5.80×10 8 t·a -1 . If the carbonation rate was 30%, the carbon storage of concrete produced annually in China during the whole life cycle reached 2.18×10 8 t, which was more than the carbon sink of Daxing'anling forest for one year. In coal electricity integrated mining areas and large thermal, metallurgical, cement chemical, and other high-energy consuming enterprises, CFC has a good prospect of development to promote the recycling of solid waste and waste gas. Meanwhile, it is pointed out that the stability of CFC before solidification is a technical problem to be solved in the next step.