Addressing climate change has become a common issue around the world in the 21st century and equally an important mission in Chinese forestry.Understanding the development of monitoring and assessment of forest biomas...Addressing climate change has become a common issue around the world in the 21st century and equally an important mission in Chinese forestry.Understanding the development of monitoring and assessment of forest biomass and carbon storage in China is important for promoting the evaluation of forest carbon sequestration capacity of China.The author conducts a systematic analysis of domestic publications addressing＂monitoring and assessment of forest biomass and carbon storage＂in order to understand the development trends,describes the brief history through three stages,and gives the situation of new development.Towards the end of the 20th century,a large number of papers on biomass and productivity of the major forest types in China had been published,covering the exploration and efforts of more than 20 years,while investigations into assessment of forest carbon storage had barely begun.Based on the data of the 7th and 8th National Forest Inventories,forest biomass and carbon storage of the entire country were assessed using individual tree biomass models and carbon conversion factors of major tree species,both previously published and newly developed.Accompanying the implementation of the 8th National Forest Inventory,a program of individual tree biomass modeling for major tree species in China was carried out simultaneously.By means of thematic research on classification of modeling populations,as well as procedures for collecting samples and methodology for biomass modeling,two technical regulations on sample collection and model construction were published as ministerial standards for application.Requests for approval of individual tree biomass models and carbon accounting parameters of major tree species have been issued for approval as ministerial standards.With the improvement of biomass models and carbon accounting parameters,thematic assessment of forest biomass and carbon storage will be gradually changed into a general monitoring of forest biomass and carbon storage,in order to realize their dynamic monitoring in national forest inventories.Strengthening the analysis and assessment of spatial distribution patterns of forest biomass and carbon storage through application of remote sensing techniques and geostatistical approaches will also be one of the major directions of development in the near future.展开更多
Underground gas storages(UGSs)rebuilt from gas reservoirs is the most popular UGS type in the world.It accounts for 75%of the total active gas of all gas storages.In order to design more scientific and reliable geolog...Underground gas storages(UGSs)rebuilt from gas reservoirs is the most popular UGS type in the world.It accounts for 75%of the total active gas of all gas storages.In order to design more scientific and reliable geological schemes for constructing the underground gas storages rebuilt from gas reservoirs and optimize the UGS operation parameters,we analyzed the UGS basic characteristics of multi-cycle high-rate injection and production.Then,the dynamic sealing capacity of traps and the wateregas high-speed interactive flow mechanism of UGSs rebuilt from gas reservoirs with complex geological conditions were investigated by both physical simulation and numerical simulation.Finally,the key technologies for evaluating the dynamic sealing capacity of caprocks and faults and the storage capacity parameters were developed.Some results were obtained.First,the alternating stress in the process of UGS injection and production weakens the original static capillary sealing capacity and mechanical integrity of caprocks to different extents,and the trap sealing capacity can be quantified and evaluated comprehensively by using dynamic breakthrough pressures,shear safety indexes and other indicators.Second,a UGS capacity design method based on effective gas-bearing pores was developed according to the local pore-based recovery mechanism revealed in the high-speed gasewater mutual flooding test.Field application in the multi-layer UGS of H shows that these technologies provide an effective guidance for the design of geologic schemes.After five cycles of injection and production,its ramp-up ratio reached 91.8%and the peak shaving capacity increased quickly to 36.3×10^(8)m^(3)from 2.7×10^(8)m^(3)in the early stage of production.Moreover,the operation indicators matched well with the design.展开更多
基金funded by the State Forestry Administration of China
文摘Addressing climate change has become a common issue around the world in the 21st century and equally an important mission in Chinese forestry.Understanding the development of monitoring and assessment of forest biomass and carbon storage in China is important for promoting the evaluation of forest carbon sequestration capacity of China.The author conducts a systematic analysis of domestic publications addressing＂monitoring and assessment of forest biomass and carbon storage＂in order to understand the development trends,describes the brief history through three stages,and gives the situation of new development.Towards the end of the 20th century,a large number of papers on biomass and productivity of the major forest types in China had been published,covering the exploration and efforts of more than 20 years,while investigations into assessment of forest carbon storage had barely begun.Based on the data of the 7th and 8th National Forest Inventories,forest biomass and carbon storage of the entire country were assessed using individual tree biomass models and carbon conversion factors of major tree species,both previously published and newly developed.Accompanying the implementation of the 8th National Forest Inventory,a program of individual tree biomass modeling for major tree species in China was carried out simultaneously.By means of thematic research on classification of modeling populations,as well as procedures for collecting samples and methodology for biomass modeling,two technical regulations on sample collection and model construction were published as ministerial standards for application.Requests for approval of individual tree biomass models and carbon accounting parameters of major tree species have been issued for approval as ministerial standards.With the improvement of biomass models and carbon accounting parameters,thematic assessment of forest biomass and carbon storage will be gradually changed into a general monitoring of forest biomass and carbon storage,in order to realize their dynamic monitoring in national forest inventories.Strengthening the analysis and assessment of spatial distribution patterns of forest biomass and carbon storage through application of remote sensing techniques and geostatistical approaches will also be one of the major directions of development in the near future.
基金supported by PetroChina Major Science and Technology Project“Study and application of geological and gas reservoir engineering technologies for underground gas storages”(No.:2015E-4002).
文摘Underground gas storages(UGSs)rebuilt from gas reservoirs is the most popular UGS type in the world.It accounts for 75%of the total active gas of all gas storages.In order to design more scientific and reliable geological schemes for constructing the underground gas storages rebuilt from gas reservoirs and optimize the UGS operation parameters,we analyzed the UGS basic characteristics of multi-cycle high-rate injection and production.Then,the dynamic sealing capacity of traps and the wateregas high-speed interactive flow mechanism of UGSs rebuilt from gas reservoirs with complex geological conditions were investigated by both physical simulation and numerical simulation.Finally,the key technologies for evaluating the dynamic sealing capacity of caprocks and faults and the storage capacity parameters were developed.Some results were obtained.First,the alternating stress in the process of UGS injection and production weakens the original static capillary sealing capacity and mechanical integrity of caprocks to different extents,and the trap sealing capacity can be quantified and evaluated comprehensively by using dynamic breakthrough pressures,shear safety indexes and other indicators.Second,a UGS capacity design method based on effective gas-bearing pores was developed according to the local pore-based recovery mechanism revealed in the high-speed gasewater mutual flooding test.Field application in the multi-layer UGS of H shows that these technologies provide an effective guidance for the design of geologic schemes.After five cycles of injection and production,its ramp-up ratio reached 91.8%and the peak shaving capacity increased quickly to 36.3×10^(8)m^(3)from 2.7×10^(8)m^(3)in the early stage of production.Moreover,the operation indicators matched well with the design.
