泥炭与煤形成环境对比研究现状

煤地质学一直偏重于对煤和含煤地层的地层学和沉积学的研究。近３０年来逐渐重视从现代聚煤作用产物－泥炭和泥炭沼泽的角度揭示,印证成煤环境问题。但苦于寻找古代煤层的合适的类比物。８０年代以来,人们逐渐把注意力集中在东南亚热带木本穹丘状高位泥炭的泥炭地,获得了大量数据资料和观察结果,开创了泥炭与煤形成环境对比研究的新局面。     

Tropical peatlands: current plight and the need for responsible management

Peatlands are important carbon stores, but when drained (e.g. for agriculture), this carbon is released to the atmosphere as carbon dioxide (CO₂, a greenhouse gas). Globally, at least 15% of peatlands have been drained, mostly in Europe and South‐east Asia, and are responsible for 5% of human‐derived CO₂ emissions. Peatlands have been exploited for generations, but not without local to global consequences, particularly in South‐East Asia. However, recognition of the continuous environmental toll caused by peatland exploitation is leading to a need to change attitudes and practices, in order to propel a move towards a more balanced and responsible use of peat in both northern and tropical peatlands.     

Effects of Lateral Variation in Vegetation and Basin ‘Dome’ Shape on Tropical Lowland Peat Stabilisation in the Kota Samarahan-Asajaya Area, West Sarawak, Malaysia

Field surveys indicate lateral variation in peat humification levels （von Post） in dominantly occurring fibric,fibric to hemic,sapric and hemie to sapric peats across a gradient from the margin towards the centre of tropical lowland peat domes.Cement-peat stabilisation can be enhanced by adding mineral soil fillers （silt,clays and fine sands） obtained from Quaternary floodplain deposits and residual soil （weathered schist）.The unconfined compressive strength （UCS） of the stabilised cement-mineral soil fifler-peat mix increases with the increased addition of selected mineral soil filler.Lateral variation in the stabilised peat strength （UCS） in the top 0 to 0.5 m layer was found from the margin towards the centre of the tropical lowland peat dome.The variations in the UCS of stabilised tropical lowland peats along a gradient from the periphery towards the centre of the peat dome are most likely caused by a combination of factors due to variations in the mineral soil or ash content of the peat and horizontal zonation or lateral variation in the dominant species of the plant assemblages （due to successive vegetation zonation of the peat swamp forest from the periphery towards the centre of the tropical lowland peat dome）.     

Blanket mire formation at the Cross Lochs, Sutherland, northern Scotland

A brief review of the genesis of blanket peats is presented, together with detailed analyses of basal peats from northern Scotland. Particular attention is paid to local factors affecting peat growth and the problems of sampling and interpretation arising from them. Macrofossil and loss-on-ignition analyses of four peat-mineral interfaces solve many of the terminological problems of such profiles and indicate that interpretations based on field stratigraphy alone are uncertain. Pollen analyses of two profiles from contrasting microtopographic situations show well-defined vegetational change associated with early peat development. Fully organic ombrotrophic peat is present from 6805 ± 50 BP at one site, following anthropogenic burning from c . 7500 BP and partial recovery of the open birch woodland. A change from birch woodland to Calluna heath occurs at approximately the same time on a more freely drained site with much later peat development, following further burning from 4890 ± 65 BP. Anthropogenic activity is clearly associated with changes in soil and vegetation preceding peat formation, and the role of climatic factors remains equivocal.     

The plight of Amazonia's oldest peatland

Peatlands are globally important ecosystems in terms of biodiversity, hydrology, and for the role they play in the carbon cycle. They store approximately one‐third of the carbon contained in the terrestrial biosphere, whilst covering only approximately 3% of the land and freshwater surface. Tropical peatlands represent an important component of this carbon store and can be found in Asia, Africa, South and Central America. However, tropical peatlands are also under severe threat of destruction from human activities including deforestation, agricultural expansion and resource exploitation. In South America, the Pastaza–Marañon foreland basin (PMFB) in NW Peru represents the most carbon dense landscape in Amazonia due to an abundance of peatlands, including nutrient‐poor ombrotrophic peat domes and river‐influenced minerotrophic swamps. The Aucayacu peatland in the PMFB is a nutrient‐poor peat dome and represents the oldest peatland yet reported in Amazonia. It is a relatively large peatland—it is estimated that Aucayacu has maximum dimensions of 33 km (NW‐SE) by 15 km (NE‐SW) (Fig. 1 ). The flora of the site is characterized by stunted vegetation due to low nutrient status, known as ‘pole’ and ‘dwarf’ forest, which at Aucayacu grows above a patchy understory of grasses and ferns (Fig. 2 ). Recent research has shown that Aucayacu has laid down peat up to 7.5 m deep in ～ 8900 years.     

Microfacies and depositional environment of Tertiary Tanjung Enim low rank coal, South Sumatra Basin, Indonesia

The South Sumatra basin is among the most important coal producing basins in Indonesia. Results of an organic petrography study on coals from Tanjung Enim, South Sumatra Basin are reported. The studied low rank coals have a mean random huminite reflectance between 0.35% and 0.46% and are dominated by huminite (34.6–94.6 vol.%). Less abundant are liptinite (4.0–61.4 vol.%) and inertinite (0.2–43.9 vol.%). Minerals are found only in small amounts (0–2 vol.%); mostly as iron sulfide.Based on maceral assemblages, the coals can be grouped into five classes: (1) humotelinite-rich group, (2) humodetrinite-rich group, (3) humocollinite-rich group, (4) inertinite-rich group and (5) humodetrinite–liptinite-rich group. Comparing the distribution of maceral assemblages to the maceral or pre-maceral assemblages in modern tropical domed peat in Indonesia reveals many similarities. The basal section of the studied coal seams is represented typically by the humodetrinite–liptinite-rich group. This section might be derived from sapric or fine hemic peat often occurring at the base of modern peats. The middle section of the seams is characterized by humotelinite-rich and humocollinite-rich groups. The precursors of these groups were hemic and fine hemic peats. The top section of the coal seams is typically represented by the humodetrinite-rich or inertinite-rich group. These groups are the counterparts of fibric peat at the top of the modern peats. The sequence of maceral assemblages thus represents the change of topogenous to ombrogenous peat and the development of a raised peat bog.A comparison between the result of detailed maceral assemblage analysis and the paleodepositional environment as established from coal maceral ratio calculation indicates that the use of coal maceral ratio diagrams developed for other coal deposits fails to deduce paleo-peat development for these young tropical coals. In particular, mineral distribution and composition should not be neglected in coal facies interpretations.     

Peatland GDGT records of Holocene climatic and biogeochemical responses to the Asian Monsoon

Branched and isoprenoidal glycerol dialkyl glycerol tetraether (GDGT) membrane lipids have been widely used to reconstruct past climate and environmental change. They are not, however, widely applied to peat deposits and the controls on their distributions in peats remain unclear. Here, we present a high resolution record of branched and isoprenoid GDGT concentrations and distributions from a peat core from the Tibetan Plateau that spans the last 13 kyr, a period characterised by distinct dry and wet periods in the region. The lowest concentrations of total branched glycerol dialkyl glycerol tetraethers (brGDGTs) occurred during a presumably dry interval in the mid-Holocene, suggesting that brGDGTs-producing bacteria are less productive under such conditions, perhaps reflecting their putative anaerobic ecology. The mean annual air temperature (MAT) estimates derived from the methylation index of brGDGTs and cyclisation ratio of brGDGTs (MBT′/CBT) are higher than present mean annual temperature in the region and closer to summer temperatures, perhaps due to seasonal production of brGDGTs. The downcore distributions of isoprenoidal and branched GDGTs are dominated by GDGT-0 and brGDGT II, respectively. The high fractional abundances of GDGT-0 in warm and especially wet intervals suggest that these conditions are favourable for some groups of methanogenic archaea. The mid-Holocene dry interval is associated with an increase in the fractional and absolute abundance of crenarchaeol, which could be indicative of enhanced ammonia-oxidising archaeal-mediated nitrogen cycling under these conditions. Taken together, variations of GDGT concentrations in peats appear to document the response of microbial processes to climate change and variations in the biogeochemical environment.     

Opaline and Al–Si phytoliths from a tropical mire system of West Malaysia: abundance, habit, elemental composition, preservation and significance

Abundant and unique opaline and Al–Si phytoliths and opaline bioliths have been discovered in Holocene peat deposits of tropical Tasek Bera in Peninsular Malaysia. These are secreted mainly by plants (higher plants and algae) and incorporated in the sediment cycle during the rapid biomass turnover. Many wetland plants have entire skeletons secreted. The study shows that differing plant parts of same species as well as same parts of differing plant species incorporate different amounts of elements. Whilst deciduous trees of the swamp forest have phytoliths enriched in Al, most phytoliths of palms, sedges and grasses of the littoral swamp are composed of opaline silica. Incorporation of Al and many other elements into relatively stable phytoliths is the result of high evapotranspiration rate and ample plant-available elements and can serve to detoxify the soil solution. Because of the abundance of such opaline and Al–Si structures, spongillid and algal remains in acid peat-accumulating environments, tropical peatlands represent repositories of Si and Al, which together with variable amounts of other elements could provide the prime material for silicate neoformation during later diagenetic processes. Neoformation of minerals from bioliths would explain the scarcity of biogenic remains in Carboniferous and Tertiary coal deposits. Furthermore, incorporation of major elements in phytoliths may limit the rate of leaching of these elements in an environment where biomass turnover is rapid, thus reducing the loss of nutrients and other plant-essential elements. Most nutrients of tropical peats are recycled by plants within the top 150 cm and an upward migration of plant-essential elements, such as Mg, Ca, or P, but also of Si and Al, occurs during peat accumulation. Such elemental cycling strongly influences the geochemical composition of the peats during mire evolution. Utilizing Al for normalization of major and minor elements of tropical peats for paleoclimatic and paleodepositional analyses may thus result in incorrect interpretations.     

Characterization and quantification of inorganic constituents of tropical peats and organic-rich deposits from Tasek Bera (Peninsular Malaysia): implications for coals

Since the Carboniferous, tropical latitudes have been the site of formation of many economic coal deposits, most of which have a restricted range of mineralogical composition as a result of their depositional environment, climatic conditions, and diagenesis. Mineralogical and microscopic investigations of tropical peats from Tasek Bera, Peninsular Malaysia, were performed in order to better understand some of these factors controlling the nature, distribution and association of inorganic matter in peat-forming environments. Distribution and nature of the inorganic fraction of peat deposits give insight into the weathering conditions and detrital input into the mire system. Because the inorganic composition of peat deposits is determined by plant communities, height of water table, and climate, the results of the quantitative and qualitative analysis can be used to reconstruct palaeoclimatic conditions.Tasek Bera is a peat-accumulating basin in humid tropical Malaysia with organic deposits of low- to high-ash yield and thus representative of many ancient peat-forming environments. Clay minerals dominate the mineralogical composition of the peat and organic-rich sediments, while quartz and clays dominate the underlying siliciclastic deposits. Kaolinite is the most abundant clay mineral in the organic deposits with minor amounts of illite and vermiculite. Particle size analyses indicate that >50% of the inorganic detrital fraction is <2 μm. Most detrital quartz grains range in size from fine silt to fine sand. The fine sand fraction accounts for a maximum of 5 wt.% of the inorganic constituents. In addition, abundant biogenic and non-biogenic, Al- and Si-rich amorphous matter occur. In the ombrotrophic (low-nutrient) environment, biogenic inorganic material contributes up to >75% of the ash constituents. As a consequence, the vegetational communities make an important contribution to the inorganic and overall ash composition of peats and coals. The ash content of the often inundated peat consists on average of 10% opaline silica from diatoms and sponge spicules, while the ash of the top deposits may have up to 50% biogenic silica. Hence, Al- and Si-hydroxides and the opaline silica from diatoms and sponges represent a large repository of Al and Si, which may form the basis of mineral transformation, neoformation and alteration processes during coalification of the peat deposits. As a result, most coal deposits from paleotropical environments are anticipated to have little to no biogenic inorganic material but high amounts of secondary clays, such as kaolinite (detrital kaolinite, resilisified kaolinite, or desilisified gibbsite) or illite, and various amounts of detrital and authigenetic quartz.     

Peat mounds of southwest Tasmania: Possible origins

Small mounds of peat rise several metres above the level of the water‐table at Melaleuca Inlet and Louisa Plains on the buttongrass plains in southwest Tasmania. Possible origins of the peat mounds have been explored by pollen analysis and radiocarbon dating of a set of samples taken from a vertical section of one peat mound at Melaleuca. The peat accumulation is entirely of Holocene age although the mound is underlain by sapric peats preserving a cold climate palynoflora of probable Late Pleistocene age. Peats at and near the base of the mound accumulated under a heath sedgeland during the earliest Holocene while after about 7630 a BP the peat‐forming vegetation was shrub‐dominated. The radiocarbon data indicate two main phases of overall peat accumulation, between 7630 and 5340 a BP (Middle Holocene) and between 4450 and 450 a BP (Late Holocene), that were interrupted by a wildfire which burnt into the surface peats. The maintenance of high surface and internal levels of moisture almost certainly was the critical factor behind the low incidence of in situ fires burning into the surface peats on the mound. The perennial influx of groundwater below the mound is a possible origin that fits well with our observations, although the expansion and contraction of soils cannot be discounted as an initiating factor. Enhanced nutrient input from birds may have helped promote growth in the peat‐forming communities. The data do not support the mounds being eroded remnants of a former blanket peat cover or being due to periglacial activity. The peat mounds of southwest Tasmania deserve maximum protection because of their rarity in the Australian landscape and, it seems, elsewhere.     

成煤母质形成环境对热成因煤层气氢碳同位素的影响:不同气候环境的草本沼泽泥炭热模拟实验

煤层气的成因研究可以为煤层气勘探与开发提供科学依据,然而,煤层气的氢碳同位素组成受多种因素的影响,以前较多的研究是成气母质性质和成熟度对煤层气氢碳同位素的影响,对于成煤物质形成的气候环境对热解煤层气同位素的影响尚不清楚.热解模拟了高纬度寒冷干旱和低纬度热带湿润环境的草本泥炭,对热解烃类气体的氢碳同位素组成及其差异性进行了研究.研究结果表明:与低纬度热带湿润环境中形成的草本泥炭相比较,高纬度寒冷干旱环境的草本泥炭热解甲烷、乙烷和丙烷具有轻的氢同位素组成和重的碳同位素组成,并且从泥炭连续热解至R_o分别为2.5%、3.5%和5.5%时,甲烷、乙烷和丙烷δD值分别平均降低-17‰~-10‰、-32‰~-28‰和-25‰~-17‰,甲烷和乙烷δ13C值分别平均升高2.9‰~3.6‰和0.9‰~1.1‰.认为这种同位素差异起因于气候环境对形成泥炭的植物氢碳同位素组成的影响.建立了高纬度寒冷干旱和低纬度热带湿润环境中形成的成煤有机质热解烃类气体氢碳同位素组成与R_o之间的关系式,同时也建立了烃类气体的碳和氢同位素之间的关系式.这些研究成果为不同气候环境下形成的成煤有机质生成的煤层气成因研究提供了科学依据.      

神农架大九湖不同生境表土磷脂脂肪酸揭示的微生物群落结构差异

磷脂脂肪酸(phospholipid fatty acid,PLFAs)是活体微生物细胞膜的重要组成部分,微生物通过改变细胞膜中PLFA组成,快速响应环境变化.目前,表土PLFAs研究主要集中于季节和植被群落变化对微生物群落结构影响,对于不同生境下表土PLFAs揭示的微生物群落结构的差异性尚不明确.基于此,对神农架大九湖7种不同生境表土进行PLFAs研究.结果表明,表土样品PLFAs集中分布于C₁₄到C₁₉;除湿生泥炭沼泽和湿生半退化沼泽生境外,其他生境以n16:0为主峰.不同生境的PLFAs含量差异较大,沼泽生境TPLFAs含量是草甸及阔叶林生境下的3~8倍.PLFAs组成还揭示出生境间主要受到pH和含水率的影响,微生物群落结构存在差异.不同生境下表层土壤PLFAs揭示的微生物丰度和群落结构具有一定的相似性及差异性.运用PLFAs对微生物量及微生物群落结构的划分将有助于更好的了解区域生态系统中微生物群落结构的变化,为研究微生物参与碳循环及古生态研究奠定基础.      

Petrological and organic geochemical investigation of recent peats with known environments of deposition

A series of recent peat samples from tropical, sub-tropical and temperate locations were investigated using coal petrographical and organic geochemical techniques. Maceral and biomarker compositions were examined to see if they correlated or diverged from the known environment of deposition of the peats.The proportion of humotelinite was related to the water depth and the frequency of dry periods. The pH and trophic level have a modifying influence on the preservation of tissues. Furthermore, the proportions of sclerotinite in the peats seem to reflected the oxygen status in the mire, which was also mirrored in the abundance of humic and fulvic acids.A facies diagram was calculated for the peat samples to see how maceral indices would fare in interpreting their known environments of deposition. The results proved to be generally unsuccessful as the herbaceous and woody peats did not always give the predicted high humodetrinite and humotelinite compositions, respectively.The aliphatic hydrocarbon fraction from the extracts of the peat samples show that mainly odd-numbered n-alkanes are present. Diterpenoids, triterpenoids and hopanoids were found in most samples and were mainly unsaturated in nature. The relative proportion of hopanoids in pears appears to be related to bacterial activity in acidic environments. De-A-triterpenoids were also detected in the peat stage of diagenesis.In an angiosperm dominated peat type (Mariscus), polycyclic aromatic triterpenoids were present in the aromatic fraction of the extract. Their occurrence and proportion appears to be related to the degree of humification. In a Taxodium peat, mono-, di-and triaromatic diterpenoids were detected. The presence of these aromatic biomarkers indicate the rapid formation of these compounds in the peat stage, mainly mediated by microbial activity.     

Conceptual models for short‐eccentricity‐scale climate control on peat formation in a lower Palaeocene fluvial system,north‐eastern Montana (USA)

Fluvial systems in which peat formation occurs are typified by autogenic processes such as river meandering, crevasse splaying and channel avulsion. Nevertheless, autogenic processes cannot satisfactorily explain the repetitive nature and lateral continuity of many coal seams (compacted peats). The fluvial lower Palaeocene Tullock Member of the Fort Union Formation (Western Interior Williston Basin; Montana, USA ) contains lignite rank coal seams that are traceable over distances of several kilometres. This sequence is used to test the hypothesis that peat formation in the fluvial system was controlled by orbitally forced climate change interacting with autogenic processes. Major successions are documented with an average thickness of 6·8 m consisting of ca 6 m thick intervals of channel and overbank deposits overlain by ca 1 m thick coal seam units. These major coal seams locally split and merge. Time‐stratigraphic correlation, using a Cretaceous–Palaeogene boundary event horizon, several distinctive volcanic ash‐fall layers, and the C29r/C29n magnetic polarity reversal, shows consistent lateral recurrence of seven successive major successions along a 10 km wide fence panel perpendicular to east/south‐east palaeo‐flow. The stratigraphic pattern, complemented by stratigraphic age control and cyclostratigraphic tests, suggests that the major peat‐forming phases, resulting in major coal seams, were driven by 100 kyr eccentricity‐related climate cycles. Two distinct conceptual models were developed, both based on the hypothesis that the major peat‐forming phases ended when enhanced seasonal contrast, at times of minimum precession during increasing eccentricity, intensified mire degradation and flooding. In model 1, orbitally forced climate change controls the timing of peat compaction, leading to enhancement of autogenic channel avulsions. In model 2, orbitally forced climate change controls upstream sediment supply and clastic influx determining the persistence of peat‐forming conditions. At the scale of the major successions, model 2 is supported because interfingering channel sandstones do not interrupt lateral continuity of major coal seams.     

Physicochemical characteristics and levels of microbial activity in some florida peat swamps

Although microorganisms are certainly present in swamp and marsh peats, their geochemical role has not been demonstrated, in spite of their importance in determining the input to coalification processes. In order to obtain information on the gross level of microbial activity in the natural habitats, a broad-spectrum test for a type of enzyme important in the respiration of all organisms has been applied to cores of peat from a number of different environments in the Florida Everglades. In most cases, the respiratory activity in the upper layer is comparable to that in a fertile mineral soil, and this level of activity is found also at greater depths in several cores. In addition, some properties of the peat that tend to define their character as habitats for microorganisms were determined. pH values close to neutrality were observed at all sites. Chlorinity and total ionic strength naturally were high in the coastal swamps; seasonal variations in profiles in the brackish areas somewhat away from the coast suggested that some bulk flow of water through the peat into the porous limestone bedrock occurs in the rainy season. Eh profiles, regarded as empirical characterizations of environments, did differ considerably between saline and fresh water peats, though on a graphite indicator electrode were more positive than might have been expected in systems in which sulfate reduction was active. However, in these non-equilibrium systems, the potential recorded apparently depends on the nature of the electrode material used.     

泥炭沉积与气候变化的泥炭记录

气候变化是影响全球泥炭沼泽分布和演化的最重要的因子之一,而泥炭地由于自身的特点成为过去气候变化的良好地质档案。在介绍泥炭沉积过程及不同类型的泥炭沼泽的发育特点基础上,从过去气候变化的常用泥炭记录和泥炭地碳记录等方面总结了国际上针对泥炭地反演气候变化研究的若干重要进展,重点剖析了泥炭腐殖化度、植物残体、有壳变形虫、生物标志化合物、同位素和孢粉等泥炭地过去气候变化重建的代用指标的适用范围和优缺点,同时也分析了泥炭地碳累积和碳循环等热点研究问题。最后从泥炭地作为过去气候变化的记录档案、泥炭地对现在气候变化的响应与反馈及在泥炭地进行现场气候变化监测与实验等方面对泥炭地与气候变化研究进行了展望。     

Sedimentology of Fraser River delta peat deposits: A modern analogue for some deltaic coals

On the Recent lobe of the Fraser River delta peat accumulation has actively occurred on the distal lower dilta plain, the transition between upper and lower delta plains, and the alluvial plain.Distal lower delta plain peats developed from widespread salt and brackish marshes and were not influenced appreciably by fluvial activity. Lateral development of the marsh facies were controlled by compaction and eustatic sea level rise. The resulting thin, discontinuous peat network contains numerous silty clay partings and high concentrations of sulphur. Freshwater marsh facies formed but were later in part eroded and altered by transgressing marine waters. The peats overlie a thin, fluvial, fining-upward sequence which in turn overlies a thick, coarsening-upward, prodelta—delta front succession.Lower delta plain—upper delta plain peats initially developed from interdistributary brackish marshes and were later fluvially influenced as the delta prograded. The thickest peats occur in areas where distributary channels were abandoned earliest. Sphagnum biofacies replace sedge-grass-dominated communities except along active channel margins, where the sedge-grass facies is intercalated with overbank and splay deposits. The peats are underlain by a relatively thin sequence of fluvial deposits which in turn is underlain by a major coarsening-upward delta front and pro-delta sequence.Alluvial plain peats accumulated in back swamp environments of the flood plain. Earliest sedge-clay and gyttjae peats developed over thin fining-upward fluvial cycles or are interlaminated with fine-grained flood deposits. Thickest accumulations occur where peat fills small avulsed flood channels. Overlying sedge-grass and Sphagnum biofacies are horizontally stratified and commonly have sharp boundaries with fine-grained flood sediments. At active channel margins however, sedge-grass peats are intercalated with natural levee deposits consisting of silty clay. These levees reduce both the number and size of crevasse splay deposits.Coal originating from peats of the different environments of the Fraser delta would vary markedly in character. Peats of the lower delta plain will form thin lenticular coal seams with numerous splits and have a high ash and sulphur content. Peats from the lower to upper delta plain will be laterally extensive and of variable thickness and quality. Basal portions of the seams will contain numerous splits and have a high sulphur content whereas upper portions will be of higher quality. Peats from the upper delta plain—alluvial plain will form thick, isolated and laterally restricted coal seams characterized by low ash and sulphur contents.     

黑碳在全球气候和环境系统中的作用及其在相关研究中的意义

燃烧形成的黑碳粒子进入大气中可影响辐射平衡,导致全球气候变暖,其沉降在河流、湖泊、海洋、土壤等环境中对全球生物地球化学循环起到重要的作用,成为当前国际地球科学研究的热点问题。综述了黑碳的定义及排放、沉降、降解过程,并总结了其在现在及过去环境和气候系统中的重要作用与研究意义。黑碳是全球惰性有机碳库的重要组成部分,在全球慢速碳循环中发挥潜在作用。因其具有很强的吸光特性,它在区域气候变暖过程中扮演重要角色。沉降在不同地质载体中的黑碳难以降解,可以保存几百万年,为地质历史时期古气候和古环境重建研究提供重要信息。海洋沉积物过去数百万年的黑碳记录指示了天然火的演化信息,晚第四纪黄土剖面黑碳也指示了天然火的变化信息,最近千年的湖泊和冰芯黑碳记录既反映了天然火的信息,也指示人类活动的信号。未来黑碳研究应进一步关注标准测量方法,以真正理解黑碳在全球气候与环境系统中的作用。     

Climate Change and Silk Road Civilization Evolution in Arid Central Asia: Progress and Issues

Arid central Asia is one of the regions most sensitive to global climate change, as well as the region with dramatically hydrological changes and fragile ecosystems. The region includes the main body of the ancient Silk Road, which played a key role in the cultural exchange and the rise and fall of Silk Road civilization. Scientific assessment of the risks faced by the sustainable development of human society in the arid central Asia under the background of global warming is a major scientific issue that has received much attention. The study of the relationship between cultural exchange, development of Silk Road civilization and climate change can provide a scientific basis for understanding the evolution rules of human-land relationship on different timescales in this area. This study summarized the research progress in the history of cultural exchanges, the rise and fall of Silk Road civilization, climate change during the Holocene, forcing mechanisms of climate and hydrological change on different timescales, as well as the process and rule of human-environment interaction. On this basis, we proposed that the study of the temporal and spatial patterns of Holocene climate change and the evolution of Silk Road civilization in arid central Asia, as well as the research on the interaction mechanisms between human and environment, are obviously insufficient. Solving the problems of regional imbalance of climate change and cultural evolution in arid central Asia and strengthening the cross-disciplinary study of geoscience and archaeology are effective ways to promote the study of climate change and changes of Silk Road civilization, which has important scientific and practical significance for understanding the evolution of human-land relations in the region, coping with the challenges of climate change, and serving the “One Belt, One Road” strategy.     

未来不同排放情景下气候变化预估研究进展

概述未来不同排放情景下气候变化预估研究的主要进展。首先,对用于开展气候变化预估研究的不同复杂程度的气候系统及地球系统模式及其模拟能力进行了简要的介绍,指出虽然目前气候系统模式在很多方面存在着较大的不确定性,但大体说来可提供当前气候状况的可信模拟结果;进而介绍了IPCC不同的排放情景,以及不同排放情景下全球与东亚区域气候变化预估的主要结果。研究表明,尽管不同模式对不同情景下未来气候变化预估的结果存有差异,但对未来50～100年全球气候变化的模拟大体一致,即全球将持续增温、降水出现区域性增加。在此基础上,概述了全球气候模式模拟结果的区域化技术,并重点介绍了降尺度方法的分类与应用。同时对气候变化预估的不确定性进行了讨论。最后,对气候变化预估的研究前景进行了展望,并讨论了未来我国气候变化预估研究的重点发展方向。