Research on the Spatial and Temporal Differences of China’s Provincial Carbon Emissions and Ecological Compensation Based on Land Carbon Budget Accounting

The establishment of a complete carbon ecological compensation mechanism is of great significance for China to achieve “carbon peak and carbon neutrality” as soon as possible. From the perspective of land carbon budget accounting, this paper measures the carbon emissions and the value of carbon ecological compensation in 30 provinces in China from 2010 to 2019, by constructing a carbon ecological compensation model, and analyzes it from both time and space perspectives. The study found that: (1) during the period 2010–2019, China’s carbon absorption remained basically stable, and woodland and grassland were the main carriers of China’s land carbon absorption. The total carbon sequestration of woodland and grassland showed a pattern of being high in the west and low in the east, and the total carbon sequestration of cultivated land showed a pattern of being high in the east and low in the west. (2) Construction land is the main source of carbon emissions in China. Cultivated land carbon emissions mainly come from major agricultural provinces such as Henan and Heilongjiang, while construction land carbon emissions are mainly concentrated in energy-consuming provinces such as Shandong and Shanxi. (3) After revising the carbon compensation benchmark value, it is found that provinces such as Guangdong and Jiangsu should receive carbon ecological compensation, while provinces dominated by heavy industries such as Shanxi and Shandong need to pay corresponding carbon compensation fees. Finally, this article puts forward corresponding policy recommendations, such as that China should give full play to the role of the government and the market, accelerate the optimization and improvement of the ecological resource asset property rights system, and optimize the development and utilization of land.

Fullerite C60 optical constants in the C 1s NEXAFS region

Using data on the absorption cross sections the refraction coefficient spectral dependence n(E) and the spectra of the remaining optical coefficients (reflection coefficient, phase shift, and atomic form factor) in the fullerite C60 C 1s near edge X-ray absorption fine structure (NEXAFS) region (280–350 eV) were determined. For the n(E) calculations the Kramers-Kronig integral relations (KKRs) were used. The KKR computations were performed using data on atomic carbon absorption cross sections in the 10–30000 eV range and on solid and gaseous C60 – in the 0–120 eV. Absorption cross section spectrum in the fullerite C60 C 1s NEXAFS region were measured.

Methodological approaches to the formation of a unified national system of monitoring and accounting of carbon balance and greenhouse gas emissions on lands of the agricultural fund of the Russian Federation

Methodological approaches to the formation of a unified national system for monitoring and accounting the balance of carbon and greenhouse gas emissions are considered. The purpose, typification, requirements for the spatial placement of “carbon” polygons, assessment of the carbon absorption capacity of forests and agricultural ecosystems in the Russian Federation, the standard methodology recommended by the international community for assessing carbon stocks in soils, which should be applied in the Russian Federation to ensure comparability of the results of greenhouse gas accounting between countries, determination of the carbon absorption capacity of natural ecosystems and soils are discussed. The potential of carbon uptake by agricultural soils is shown. The list of indicators for assessing soil carbon according to the IPCC methodology for Tiers 2 and 3 is given. Taking into account the analysis of international practice, as well as on the basis of theoretical and applied experience of national science, the priority measures have been developed, they are aimed at working out and implementation of the national strategy for the use of terrestrial ecosystems in order to regulate greenhouse gas emissions to mitigate climate change.

A Decrease in Carbon Absorption Potential Due to Timber Harvesting in Natural Forest

Timber harvesting is an activity in producing wood to supply the lumber industry. However, timber harvesting brought consequences such as decreasing carbon sequestration potential of natural forests. This study aimed to determine the reduction in the potential for carbon sequestration due to timber harvesting in natural forests. Data were collected using non-destructive methods through stand inventory before felling for all tree species, cruising results report, and tree distribution maps. Biomass was calculated using the existing allometric, and carbon stocks were calculated using the Intergovernmental Panel on Climate Change method. The results showed that there were 238 trees (65.29 m3) of stands in the study area (6 ha) based on stand inventory before felling. Potential biomass and carbon storage before trees felling were 16.12 ton ha-1 and 7.58 ton ha-1, respectively. Potential biomass and carbon storage after tree felling were 5.15 ton ha-1 and 2.42 ton ha-1, respectively. Carbon absorption before and after tree felling is 28.37 ton CO2eq ha-1 and 4.44 ton CO2eq ha-1, respectively. Carbon emissions during tree felling was 18.93 ton CO2eq ha-1 (81.00%). The application of environmentally friendly wood harvesting shall be carried out appropriately to minimize a decrease in carbon absorption from timber harvesting. Keywords: biomass, carbon emission, timber harvesting

Analisis Perubahan Penutupan Lahan dan Potensi Karbon di Taman Hutan Raya Pocut Meurah Intan, Aceh Indonesia

Perubahan penutupan lahan merupakan sektor penyumbang emisi gas rumah kaca terbesar, termasuk di dalamnya adalah pemanfaatan lahan. Analisis tutupan lahan menjadi bagian penting dalam menentukan jumlah potensi karbon yang tersedia. Penelitian bertujuan untuk menganalisis perubahan tutupan lahan dari tahun 2003 hingga 2018 dan menghitung potensi karbon di Taman Hutan Raya Pocut Meurah Intan dengan luas objek penelitian 6.215 ha. Penelitian dilaksanakan selama 5 (lima) bulan. Penelitian ini menggunakan metode stock difference, yaitu metode perhitungan luas tutupan lahan dan stok karbon pada dua titik waktu. Hasil penelitian menunjukkan bahwa perubahan luas tertinggi tahun 2018 seluas 263 ha dan terendah tahun 2009 seluas 108 ha. Lahan terbuka meningkat seluas 100 ha, pemukiman 81 ha, semak belukar 65 ha, pertanian lahan kering campur semak 32 ha. Sementara hutan lahan kering sekunder menurun 79 ha, hutan tanaman 76 ha, savanna 21 ha dan pertanian lahan kering 103 ha. Selama kurun waktu 15 tahun berdasarkan kelas penutupan lahan, cadangan karbon tertinggi pada tahun 2003 sebesar 656.053 ton, terendah tahun 2012 sebesar 620.992 ton. Laju serapan karbon tertinggi pada periode tahun 2015-2018 sebesar 94.615 ton CO2 dan terendah pada periode tahun 2009-2012 sebesar 1.981 ton CO2. Laju emisi tertinggi pada periode tahun 2003-2006 sebesar 79.559 ton CO2 dan terendah periode tahun 2006-2009 sebesar 9.069 ton CO2. Peningkatan serapan karbon diakibatkan oleh meningkatnya luas tutupan lahan pada hutan lahan kering sekunder dan adanya pemanfaatan lahan untuk pertanian lahan kering campur semak.ABSTRACTChanges in land cover are the largest contributor to greenhouse gas emissions, including land use. Land cover analysis is an important part in determining the potential amount of carbon available. The study aims to analyze changes in land cover from 2003 to 2018 and calculating the carbon potential in the Pocut Meurah Intan Forest Park with a research object area of 6,215 ha. The research was conducted for 5 (five) months. This research uses the stock difference method, namely the method of calculating land cover area dan stok karbon pada dua titik waktu. The results showed that the highest area change in 2018 was 263 ha and the lowest was in 2009 at 108 ha. Open land increased by 100 ha, settlement 81 ha, scrub 65 ha, dry land agriculture mixed with shrubs 32 ha. Meanwhile, secondary dry land forest decreased by 79 ha, plantation forest 76 ha, savanna 21 ha and dry land agriculture 103 ha. Over a 15 year period based on land cover class, the highest carbon stock in 2003 was 656,053 tons, the lowest was in 2012 at 620,992 tons. The highest carbon absorption rate in the 2015-2018 period was 94,615 tons of CO2 and the lowest was in the 2009-2012 period of 1,981 tons of CO2. The highest emission rate in the 2003-2006 period was 79,559 tonnes of CO2 and the lowest for the 2006-2009 period was 9,069 tonnes of CO2. The increase in carbon sequestration is caused by the increase in land cover in secondary dryland forest and the use of land for mixed dry land agriculture.

Effects of black carbon morphology on brown carbon absorption estimation: from numerical aspects

In this work, we developed a numerical method to investigate the effects of black carbon (BC) morphology on the estimation of brown carbon (BrC) absorption using the absorption Ångström exponent (AAE) methods. Pseudo measurements of the total absorption were generated based on several morphologically mixed BC models, then the BrC absorption was inferred based on different BC AAE methods. By investigating the estimated BrC absorption at different parameters, we have demonstrated under what conditions the AAE methods can provide good or bad estimations. As recent studies have shown that both externally and internally mixed BC still exhibits a relatively small fractal dimension value, the AAE = 1 method is still a reasonable method to estimate the BrC absorption as the AAE of fluffy BC does not deviate significantly from 1. However, the deviation between the “true” and the estimated BrC mass absorption cross section (MAC) should also be carefully considered as sometimes the MAC deviation estimated using the AAE = 1 method can reach a value that is comparable to the true BrC MAC for internally mixed particles. The Mie AAE method can just provide relatively reasonable estimations for small particles, and the BrC absorption deviations estimated using the Mie AAE methods are rather substantial for large particles. If the BC core still exhibits a fluffy structure, the deviation between the true and the estimated BrC MAC can reach 4.8 and 5.8 m2/g for large externally and internally mixed particles, respectively. Even for a compact BC core, the BrC MAC deviation estimated using the Mie AAE method can reach approximately 2.8 m2/g when the BC size is large. By comparing the AAE of spherical BC and detailed BC models, we found that the AAE does not deviate significantly from 1 if BC presents a fluffy fractal structure, while it varies considerably with particle size if BC exhibits a spherical structure, and the AAE value of spherical BC can vary from a negative value to approximately 1.4. The precalculated wavelength dependence of AAE (WDA) method does not necessarily improve the estimations. In many cases, the WDA method even provides a worse estimation than the BC AAE =1 and Mie AAE methods. Our results showed that the WDA does not deviate significantly from 0 if the BC core presents a fluffy structure, while the WDA of spherical BC can vary significantly as the particle size changes. The deviation between the true and the estimated BrC MAC using the WDA method can reach approximately 9 m2/g for externally mixed particles, which is far more than BrC MAC itself. As recent studies have shown that BC commonly exhibits a fluffy structure but not a spherical structure, the estimation of BrC absorption based on the AAE method should carefully consider the effects of BC morphologies.