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1.
《中国地理科学(英文版)》2020,(3)
The impact of human carbon emissions on climate has generated widespread global concern. We selected 24 countries as research objects and analysed the changes in carbon emissions in different countries between the establishment of emission reduction actions in 1990 and 2014. Then, we selected 19 factors representing four categories(economy, population, technology and energy) to explore the key factors that led to changes in carbon dioxide(CO_2) emissions in different countries. Emission reduction actions since 1990 did not lead to marked improvements, and only five countries(Russia, Germany, the United Kingdom, Italy and France) achieved reductions in carbon emissions. The factors that influenced CO_2 emissions varied among countries. In most developing countries, reductions in CO_2 emissions were caused by reductions in poverty and inherent natural conditions. Moreover, the extent of influence of a given factor on CO_2 emissions differed among countries. The global economic crisis may cause similar fluctuations in CO_2 emissions in many countries. Adjustments to energy and industrial structures are the main reason for the reduction in carbon emissions, whereas economic growth and urbanization are the two major contributors to the growth of carbon emissions. According to historical carbon emissions data, a green energy revolution must be implemented to address global climate change and ensure the sustainable development of human societies. 相似文献
2.
如何获取CO2浓度时空分布特征,是气候变化研究中的一个关键问题。本文基于中国碳卫星在吉林航飞试验区的地面观测数据,分析地表CO2浓度与环境变量的相关关系,运用多元线性回归与HASM高精度曲面建模相结合的方法,模拟航飞区地表CO2浓度分布格局。结果表明：CO2浓度空间分布受气象条件的影响较大,短波辐射是影响CO2浓度的重要因素;第1时段整体浓度最高,特别是在西部区域;第2时段CO2浓度高值区东移,呈现西低东高的分布特点;第3时段浓度空间分布与第2时段有类似的特征,但细节存在差异,且高值区缩小;精度对比显示在采样点较少及采样密度不大的情况下,HASM方法的模拟误差小于Kriging方法。因此,这种使用多元线性回归模型通过引入环境变量获得高分辨率趋势面,结合HASM模型进行修正残差提高模拟结果精度的手段,可作为模拟地表CO2浓度时空分布的有效方法。 相似文献
3.
Anthropogenic emission of atmospheric carbon dioxide(CO_2) has led to a rapid increase in atmospheric CO_2 concentration. Increasing atmospheric CO_2 can reduce seawater pH and carbonate ions, which may adversely affect the survival of the larvae of calcareous animals. Cyclina sinensis is a commercially and ecologically important species in several Asian countries. Living in coast shallow waters, this species has experienced the coastal environmental changes frequently throughout its life cycle. In this study, we simulated possible future seawater pH values including 8.2, 7.8 and 7.4 and examined the effects of ocean acidification on the early development of C. sinensis. Clam embryos were incubated for 48 h(2 d) in control and high-CO_2 seawater to compare embryogenesis, larval growth and swimming behavior. Fertilization rate was quite sensitive to pH, and moderate acidification could induce a significant decrease in fertilization rate. However, only extreme acidification could bring significant negative effect to hatching rate, body size, and average path velocity of trochophora. Moreover, with seawater acidification, C. sinensis needs much more time to reach the same developmental stage, which increases the risk of larva survival. Together with recent studies demonstrating negative impacts of high CO_2 on fertilization and larva swimming behavior, the results imply a future decrease of C. sinensis populations in oceans if its acclimation to the predicted environmental alteration does not occur. 相似文献
4.
《中国海洋湖沼学报》2021,(5)
The climate variability induced by the El Ni?o-Southern Oscillation(ENSO) cycle drives significant changes in the physical state of the tropical Western Pacific,which has important impacts on the upper ocean carbon cycle.During 2015-2016,a super El Ni?o event occurred in the equatorial Pacific.Suspended particulate matter(SPM) data and related environmental observations in the tropical Western Pacific were obtained during two cruses in Dec.2014 and 2015,which coincided with the early and peak stages of this super El Ni?o event.Compared with the marine environments in the tropical Western Pacific in Dec.2014,an obviously enhanced upwelling occurred in the Mindanao Dome region;the nitrate concentration in the euphotic zone almo st tripled;and the size,mass concentration,and volume concentration of SPM obviously increased in Dec.2015.The enhanced upwelling in the Mindanao Dome region carried cold but eutrophic water upward from the deep ocean to shallow depths,even into the euphotic zone,which disrupted the previously N-limited conditions and induced a remarkable increase in phytoplankton blooms in the euphotic zone.The se results reveal the mechanism of how nutrient-limited ecosystems in the tropical Western Pacific respond to super El Ni?o events.In the context of the ENSO cycle,if predicted changes in biogenic particles occur,the proportion of carbon storage in the tropical Western Pacific is estimated to be increased by more than 52%,ultimately affecting the regional and possibly even global carbon cycle.This paper highlights the prospect for long-term prediction of the impact of a super El Ni?o event on the global carbon cycle and has profound implications for understanding El Ni?o events. 相似文献
5.
大气二氧化碳是开展全球气候变化和碳循环研究的关键数据。卫星遥感技术与模式模拟相结合的反演方法已成为获取该数据的重要手段,但模式输入参数本身的误差会对大气二氧化碳反演精度产生影响,须在反演算法设计中加以关注。本文利用RTTOV10快速辐射传输模式模拟Aqua/AIRS红外探测仪17个大气二氧化碳反演通道,计算了这些通道上大气顶出射辐射对温度廓线、臭氧廓线、水汽廓线、地表温度和地表发射率的参数误差的不确定性,并与二氧化碳增加0.5%时造成的不确定性进行对比,分析二氧化碳对上述参数误差的敏感性。结果表明,温度廓线误差是干扰AIRS大气二氧化碳反演的主要因素,其次是臭氧廓线误差,而水汽廓线、地表温度和地表发射率的误差对二氧化碳反演的影响在除去个别通道后可忽略不计。最后,本文以通道为单位,确定了各通道上的高敏感参数、敏感参数和不敏感参数,为二氧化碳反演通道的选择和反演算法的设计提供了参考。 相似文献
6.
It is widely accepted that global warming, which results from the increase of carbon dioxide(CO2) in the atmosphere, has a negative impact on human beings. Forests are the largest terrestrial ecosystem and play an important role in carbon sequestration. Many studies have documented that a mixed-species forest can sequester more carbon than single species forests, depending on the site conditions. Therefore, uneven-aged mixed-species forest management has been receiving more and more attention. In 2008, an experiment with five silvicultural models for Pinus massoniana(Chinese red pine) plantation, i.e., four transformation treatments(A1-A4) and one control treatment(A5) was conducted in the Experimental Center of Tropical Forestry of Chinese Academy of Forestry in Pingxiang City, in southwestern Guangxi Zhuang Autonomous Region, southern China. The four transformation treatments(A1-A4) enriched Castanopsis hystrix, Manglietia glance, Erythrophleum fordii and Quercus griffithii with differed richness and composition after thinning(removed 70% of trees), while no silvicultural treatment was used in the control treatment A5. In this study, we compared the carbon sequestration capacity of these five silvicultural models based on periodic annual increment and growth rate. Our results indicated that all the transformation treatments performed significantly better in carbon sequestration than the control treatment. A significant difference was also observed amongst the transformation treatments. Moreover, the transformation treatment A1 with enrichment species Castanopsis hystrix(350 trees·ha^-1) and Manglietia glance(350 trees·ha^-1) was determined to be the optimal model for maximum carbon sequestration because of its high tree-level growth rate and high economic value of enriched plantings, which could be popularized in other places. Our results further confirmed that management using mixed-species forests is a better approach to combat climate change than using monoculture forests. 相似文献
7.
《山地科学学报》2020,17(7):1636-1651
The soil carbon pool which is the sum of soil organic carbon(SOC) and soil inorganic carbon(SIC) is the second largest active store of carbon after the oceans and it is an important component of the global carbon cycle. Hence, accurate estimation of SOC and SIC as important carbon reservoirs in terrestrial ecosystems using fast, inexpensive and non-destructive methods is crucial for planning different climate change policies. The aim of the current research was to examine the effectiveness of Vis-NIR(visible and near-infrared spectroscopy: 350-2500 nm) and MIR(mid-infrared spectroscopy: 4000-400 cm~(-1)) to characterize and estimate soil organic matter(SOM) and carbonates as main components of soil carbon stocks in Juneqan, Charmahal va Bakhtiari, Iran. To do so, a total of 548 soil samples from this area were collected(October 2015) and analyzed in laboratory(August 2017). In order to develop models capable of predicting SOM and carbonates content, seven spectral preprocessing methods comprising Absorbance(Abs), De-trending(Det), Continuum removal(CR), Savitzky-Golay derivatives(SGD), standard normal variate transformation(SNV), multiplicative scatter correction(MSC) and Normalization by range(NBR) were conducted along with five multivariate methods including Random Forest(RF), Partial Least-Squares Regression(PLSR), Artificial Neural Network(ANN), Support Vector Machine(SVM) and Gaussian Process Regression(GPR). The content of carbonates caused spectral reflectance intensity to augment on several ranges of spectrum and strong absorption feature at 2338 nm in the Vis-NIR and 714, 850, 870, 1796, 2150 and 2510 cm~(-1) in the MIR spectra range. SOM absorbed energy in several ranges, but also showed specific peaks in MIR. Both facts are associated with the structure of carbonates and SOM and its interaction with energy. The best combination of preprocessing and calibration models for carbonates quantification in Vis-NIR spectra was Det/PLSR(R~2= 0.74, RPD= 2.19, RMSE= 6.45). For SOM, it was Det/PLSR(R~2= 0.82, RPD= 2.41, RMSE= 0.75). The Det/RF(R~2= 0.87, RPD= 2.44, RMSE= 0.66) for the quantification of SOM and MSC/RF(R~2= 0.84, RPD= 2.84, RMSE= 5.50) for carbonates in MIR spectra range showed the greatest results. The stronger occurrence of spectral bands in MIR as well as the specificity of the absorption features indicated that this range produced better predictions. The obtained results highlighted the significant role of soil spectroscopy technique in predicting SOC and soil carbonates as key components of soil carbon stocks in the study area. Therefore, this technique can be used as a more cost-effective, time saving and nondestructive alternative to traditional methods of soil analysis. 相似文献
8.
The possible global sea level rise and its magnitude in the next century induced by the doubling of atmospheric carbon dioxide
concentration are briefly discussed. The rates of crustal sinking, ground surface aggradation, and sediment compaction which
might give rise to the regional characteristics of relative sea level (RSL) changes, are studied in detail. Attention is focused
on the following problems that are closely associated to the sea level rise in the next century: 1) the flood susceptibility
of the low-lying East China plains in the next century and its historical evidences, 2) the frequency of disastrous floods
and storm surges, 3) the aggradational rate and the potential danger to the dikes along the Changjiang River's lower reaches
and 4) the salt water intrusion and the water quality in the Changjiang River estuary. The study shows that the adverse impacts
would be very great even if only the lower estimate of sea-level rise in the next century is considered. Therefore, comprehensive
research must be conducted and decision must be made to cope with the approaching sealevel rise.
Han Jiagu, 1984. The impact of geographical changes on the history of Tianjin, paper submitted to the Symposium of Environmental
Changes. 相似文献
9.
流动人口的职住情绪能够反映其工作与生活状态。本研究首先基于2017年北京市微博大数据,利用jieba分词结合人工筛选得到流动人口发布的微博文本;其次,对Roberta-wwm-ext-large模型进行迁移学习识别北京全人群与流动人口的微博情绪;然后,结合POI数据与微博发布时间得到流动人口的职住分布;最后,基于微博情绪与职住分布得到流动人口的职住情绪,利用Getis-Ord Gi*挖掘职住情绪的空间聚集模式,采用地理探测器分析影响职住情绪热点分布的因素。实验表明,北京流动人口情绪均值（0.56）稍低于北京全人群（0.57）（P<0.01）,但整体表现为积极;从空间分布来看,流动人口在东、西城区情绪均衡,西北部科技创新区情绪相对于流动人口情绪均值较为低落,而东南部中心商务区、文化交流区及国际化社区情绪较高涨;从情绪与职住的关系来看,流动人口的工作情绪与从事的工作类型有关（q=0.03,P<0.05）,高新技术产业园、工业园、物流产业园的流动人口从业人员的工作情绪相对于流动人口工作情绪均值较为消极,健康产业园、文化创意产业园、农业园的流动人口从业人员的工作情绪较积极;流动人口的居住情绪与居住环境有关（q=0.06,P<0.1）,居住在远郊区的流动人口情绪相对于流动人口居住情绪均值较为消极,居住在近郊高密度的流动人口情绪较为积极。因此,相关部门应重点关注从事高新技术产业、工业、物流产业的流动人口以及居住在远郊区的流动人口。 相似文献
10.
With respect to the different hydrological responses of catchments, even the adjacent ones, in mountainous regions, there are a great number of motivations for classifying them into homogeneous clusters. These motivations include prediction in ungauged basins (PUB), model parameterization, understanding the potential impact of environmental changes, transferring information from gauged catchments to the ungauged ones. The present study investigated the similarity of catchments through the hydro-climatological pure time-series of a 14-year period from 2001 to 2015. Data sets encompass more than 13,000 month-station streamflow, rainfall, and temperature data obtained from 27 catchments in Utah State as one of the eight mountainous states of the USA. The identification, analysis, and interpretation of homogeneous catchments were investigated by applying the four approaches of clustering, K-means, Ward, and SOM (Self-Organized Map) and a newly proposed Wavelet-Entropy-based (WE-SOM) clustering method. By using two clustering evaluation criteria, 3, 5, and 6 clusters were determined as the best numbers of clusters, depending on the method employed, where each cluster represents different hydro-climatological behaviors. Despite the absence of geographic characteristics in input data matrix, the results indicated a regionalization in agreement with topographic characteristics. Considering the dependency of the hydrological behavior of catchments on the physiographic field aspects and characteristics, WE-SOM method demonstrated a more acceptable performance, compared to the other three conventional clustering methods, by providing more clusters. WE-SOM appears to be a promising approach in catchment clustering. It preserves the topological structure of data which can, as a result, be proofed in a greater number of clusters by dividing data into higher numbers of distinct clusters with similar altitudes of catchments in each cluster. The results showed the aptitude of wavelets to quantify the time-based variability of temperature, rainfall and streamflow, in the way contributing to the regionalization of diverse catchments. 相似文献
11.
Oceanic uptake of anthropogenic carbon dioxide results in a decrease in seawater pH, a process known as "ocean acidification". The pearl oyster Pinctada fucata, the noble scallop Chlamys nobilis, and the green-lipped mussel Perna viridis are species of economic and ecological importance along the southern coast of China. We evaluated the effects of seawater acidification on clearance, respiration, and excretion rates in these three species. The animals were reared in seawater at pH 8.1 (control), 7.7, or 7.4. The clearance rate was highest at pH 7.7 for P. fucata and at pH 8.1 for C. nobilis and P. viridis. The pH had little effecton the respiration rate of P. fucata and P. viridis. In contrast, the respiration rate was significantly lower atpH 7.4 in C. nobilis. The excretion rate was significantly lower at pH 7.4 than pH 8.1 for all species. Theresults indicate that the reduction in seawater pH likely affected the metabolic process (food intake, oxygenconsumption, and ammonia excretion) of these bivalves. Different species respond differently to seawateracidification. Further studies are needed to demonstrate the exact mechanisms for this effect and evaluateadaptability of these bivalves to future acidified oceans. 相似文献
12.
High-precision isotope composition determinations using multicollector, magnetic-sector inductively coupled plasma mass spectrometry (MC-ICPMS) have recently revealed that some transition metal isotopes such as those of Mo, Fe, Cu, Zn etc. can be used as biogeochemical tracers in global change research.The Mo isotope system may be useful in paleoredox investigations indicating that δ^97 ^95Mo in seawater may co-vary with changes in the relative proportions of anoxic and oxic sedimentation in the ocean, and that this variation may be recorded in δ^97 ^95Mo of anoxic sediments. The Mo continental flux into the oceans and the global Mo isotope budget can be estimated from δ^97 ^95M0 values. The Fe isotope composition in seawater is an important issue because Fe plays a controlling role in biological productivity in the oceans and its abundance in seawater may have substantial effect on climate changes. Iron isotope fractionations could result from bio- and abio-processes and have about 0.1% variation ( δ^56 ^54Fe), so Fe isotopes considered alone cannot be used to distinguish the products of abiotic and biotic Fe processing in geological records. Cu and Zn isotopes are also used as biogeochemical tracers, but the researches are relatively less. This review mainly focuses on the methods for preparation, purification and determination of new isotope tracer samples, and on isotope applications in marine environmental changes. 相似文献
13.
许厂煤矿下组煤中蕴藏着较为丰富的瓦斯、二氧化碳资源。下组煤位于瓦斯风化带内,含瓦斯、二氧化碳和氮气等气体,瓦斯含量与埋藏深度呈正相关关系,主要存在低含量瓦斯、二氧化碳抽采率、二氧化碳资源化转换等技术方面的问题。从国家相关优惠政策、资源优势、煤与煤层气一体化开发技术、近水平长钻孔定向钻进技术、煤层压裂造缝技术、煤层注气增产技术和瓦斯、二氧化碳气体提纯技术等关键技术的发展程度,结合煤矿的下组煤层的开采方案,认为许厂煤矿有着较好的煤炭与瓦斯、二氧化碳一体化开发利用前景。 相似文献
14.
A super El Ni?o event occurred in the equatorial Pacific during 2015-2016,accompanied by considerable regional eco-hydro-climatic variations within the Mindanao Dome(MD)upwelling system in the tropical western Pacific.Using timeseries of various oceanic data from 2013 to 2017,the variability of eco-hydro-climatic conditions response to the 2015/2016 super El Ni?o in the upper 300 m of the MD region are analyzed in this paper.Results showed that during the 2015/2016 super El Ni?o event,the upwelling in the MD region was greatly enhanced compared to those before and after this El Ni?o event.Upwelling Rossby waves and the massive loss of surface water in the western Pacific were suggested to be the main reasons for this enhanced upwelling.De-creased precipitation caused by changes in large-scale air-sea interaction led to the increased surface salinities.Changes in the struc-tures of the thermohaline and nutrient distribution in deep waters contributed to the increased surface chlorophyll a,suggesting a po-sitive effect of El Ni?o on surface carbon storage in the MD region.Based on the above analysis,the synopsis mechanism illustrating the eco-hydro-climatic changing processes over the MD upwelling system responding to the El Ni?o event was proposed.It high-lights the prospect for the role played by El Ni?o in local eco-hydro-climatic effects,which has further profound implications for understanding the influence of the global climate changes on the ocean carbon cycle. 相似文献
15.
以全球变暖和极端气候为主要特征的气候变化已成为世界各国普遍关注的重大环境问题,全球性的碳排放问题亟待解决已是非常明确的科学共识。然而城市能源消耗尤其是在街道街区尺度能源消耗空间定量化研究目前较少,不利于城市采取精准控制、优化能源结构和减少碳排放措施。本文以资源型城市荆门作为案例城市,以夜间遥感数据、POI等空间数据为基础,定量化分析影响交通、产业和建筑部门碳排放的关键因素车流量、建筑面积和主要用能企业的空间分布数据,实现城市能源消费街道尺度空间可视化,并探讨城镇化和工业化对街道尺度城市能源消费的影响。结果发现工业部门能源消费的持续增长是该市能源消费总量增长的主要驱动因子,72个乡镇（街道）中,以产业能耗为主的10个乡镇（街道）占荆门市能源消费总量达68%。荆门市总用能量在2005—2015年增长82.82万 tce,然而同时用能量高于10 000 tce的乡镇减少了4个,说明荆门市能源消耗提高并呈现集中化趋势。研究结论能够填补以城市或城区为最小单元统计城市能源消费情况所不能发现问题,提出了更加精准的降低荆门市能耗的途径,以期为同类中小资源型城市转型实现绿色发展提供借鉴。 相似文献
16.
LIU Qingzhi HU Yangdong 《中国海洋大学学报(英文版)》2008,7(1):43-47
Using molecular dynamics （MD） simulation, the diffusion of oxygen, methane, ammonia and carbon dioxide in water was simulated in the canonical NVT ensemble, and the diffusion coefficient was analyzed by the clustering method. By comparing to the conventional method （using the Einstein model） and the differentiation-interval variation method, we found that the results obtained by the clustering method used in this study are more close to the experimental values. This method proved to be more reasonable than the other two methods. 相似文献
17.
采用二氧化碳爆破致裂为激发干热岩储层提供了一种新的技术思路和途径。为了探究二氧化碳爆破致裂激发干热岩储层的作用效果, 开展了二氧化碳爆破致裂干热岩储层作用范围的数值模拟研究。考虑实际开采过程中钻井液对井壁附近干热岩储层的降温影响, 采用以温差为变量的拟合函数设置损伤区储层材料参数, 用洗井后井壁附近储层温度分布函数设置损伤区储层温度场, 并借助炸药爆破的相关理论、公式设置爆破荷载, 结合COMSOL软件模拟了二氧化碳爆破致裂激发干热岩储层的过程。结果表明, 二氧化碳爆破致裂干热岩过程中存在多次应力集中作用, 且在炮孔附近压应力集中造成压碎区, 压碎区外拉应力作用形成裂隙区; 储层的初始温度以及定压片厚度都会影响二氧化碳爆破致裂激发干热岩储层的作用效果, 其中初始温度对爆破压碎区范围影响较大, 对裂隙区范围影响较小, 定压片厚度改变对压碎区范围影响较小, 主要影响爆破裂隙区的分布。本研究成果可为干热岩地热能后续的开采利用提供理论支持和参考。 相似文献
18.
为了阐明喀斯特水库对河流水体碳循环造成的影响, 总结了近年来喀斯特流域筑坝作用对不同形态碳迁移转化和环境影响的研究进展。通过光谱学、稳定及放射性同位素等手段等对喀斯特地区河流-水库系统中的溶解无机碳(DIC)、溶解有机碳(DOC)、颗粒无机碳(PIC)和颗粒有机碳(POC)迁移转化及其控制机制的研究, 发现喀斯特水库碳循环展现出明显的季节性分布特征以及梯级水库群可能会进一步放大单个水库的生态效应, 这一结果不仅极大地促进了人们对水库碳循环的认识, 还有利于探索河流碳循环中"遗失"的碳汇以及更加准确的评估岩溶水库在全球河流碳循环中扮演的角色。喀斯特水库相比非喀斯特水库对人为活动加剧的影响可能具有更强的响应强度, 这也意味着喀斯特水库在全球变暖的趋势中发挥的作用需要得到更准确的评估, 而在未来的研究中, 通过不同分析手段从微观到宏观系统性的总结不同形态碳迁移转化特点将更准确的回答该问题。 相似文献
19.
随着生活水平的提高,人们越来越青睐含有多种微量元素的饮用天然矿泉水。受环境变化和人为因素的影响,天然矿泉水水源地受到了不同程度的污染和破坏。为了使这一有利资源得到更加有效的保护和利用,开展饮用天然矿泉水卫生防护区设定的探索成一有力举措。本文以济南某天然矿泉水为例,在调查研究的基础上,利用玫瑰图裂隙法,使该饮用天然矿泉水的卫生防护区"向源"设定,一定程度上解决了原矿泉水井卫生防护区设置存在的局限和不足,从而精准发力,落实各项保护措施。 相似文献
20.
森林碳蓄积量估算方法及其应用分析 总被引：7，自引：0，他引：7
近些年来,森林锐减、土地退化、环境污染、生物多样性丧失,特别是人类活动产生的C02浓度急剧上升和由此导致的温室效应等是目前人类面临最严峻的全球环境变化问题,所以全球碳循环问题日益成为全球变化与地球科学研究领域的前沿与热点问题,其中陆地生态系统碳循环又是全球碳循环中最复杂、受人类活动影响最大的部分。而森林生物量占整个陆地生态系统生物量的90%,因此,为了正确评估森林在全球碳平衡中的作用,了解森林生态系统在碳循环中的作用,森林的碳动态研究正日益成为人们关注的重点。本文总结了估算森林固碳量的几种方法--样地清查法、模型模拟法和遥感估算法,分析了它们的特点及应用等有关问题。 相似文献