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1.
碳捕集与封存(CCS)技术是当前抑制大气中CO2过快增长的有效方法,但在CCS项目实施过程中仍存在CO2泄漏而影响地表环境及生态的风险.本研究以龙粳31号和龙稻18号为实验对象,模拟研究地质封存CO2以不同速率泄漏对稻田水环境基础水质指标DCO2、pH、DO和ORP的影响,探讨稻田水对地质封存CO2泄漏的响应规律.结果表明:CO2泄漏对稻田水的DCO2、pH、DO和ORP长期影响显著,不同CO2泄漏速率对稻田水质指标的影响差异显著.在各指标平衡后,稻田水各水质指标均呈现明显的日变化规律,其中DCO2呈早晚高、午间低的先减后增规律,而pH、DO和ORP均呈早晚低、午间高的先增后减规律.根据各指标差异性分析,建议将稻田水DCO2作为稻田系统CO2泄漏监测的主要指标,将pH、DO、ORP作为CO2泄漏监测的辅助指标.  相似文献   

2.
缙云山不同土地利用方式下土壤植硅体碳的含量特征   总被引:1,自引:0,他引:1  
罗东海  王子芳  陆畅  黄容  王富华  李娇  高明 《环境科学》2019,40(9):4270-4277
植硅体碳是长期封存土壤有机碳的一种形式,对土壤固碳有重要意义.以西南地区常见的6种土地利用方式(针阔叶混交林、竹林、果园、旱地、水田和荒草地)为研究对象,探讨了不同土地利用方式下植硅体碳含量在不同剖面上(0~20、20~40、40~60和60~100 cm)的分布规律,并估算了植硅体碳储量,分析了陆地生态系统碳汇特征.结果表明,在6种土地利用方式中,竹林土壤有机碳和植硅体含量在土壤剖面上的平均值均为最高,分别为16. 75 g·kg-1和59. 66 g·kg-1.在4个土层,竹林土壤植硅体含量均显著高于其他土地利用方式(P 0. 05).对植硅体碳而言,6种土地利用方式下的土壤植硅体碳平均含量变化范围在0. 55~1. 96 g·kg-1,其中竹林各土层的植硅体碳含量都高于其他土地利用方式.竹林土壤植硅体碳总储量(23. 45 t·hm-2)显著高于其他土地利用方式土壤植硅体碳总储量(P 0. 05).统计分析表明,土壤全硅与土壤植硅体、土壤植硅体碳均表现出极显著的正相关关系(P 0. 01).不同土地利用方式下土壤植硅体与植硅体碳的含量总体表现为随着土层深度的增加而下降,存在一定的表层富集现象.  相似文献   

3.
本文在环境污染责任保险试点调研和数据分析的基础上,总结了近年来环境污染责任保险政策的实践发展趋势,发现环境污染责任保险政策具有趋于强制、投保范围明确且趋同、产品性价比提升、保险市场受政策影响波动大的显著特点,地方试点实践中面临缺少环境风险定价方案、事故预防难开展、政府部门权责不清及数据信息共享缺乏的现实困境;同时在分析环境污染责任保险贵州新一轮试点对环境污染责任保险试点困境的实践突破基础上,总结统一条款、统一风险定价、统一投承保平台的"贵州模式"。基于以上分析本文提出如下建议:进一步明确环境污染责任保险强制的上位法依据,建立全国统一的环境污染强制责任保险管理制度;根据环境风险形成全过程理论,采用"两步走"方式,平衡科学性与成本关系,建立保前风险评估—保后隐患排查标准体系;建立国家—省级—地市多层级多主体环境污染责任保险治理信息化平台。  相似文献   

4.
Shifts in the carbon balance of high-latitude ecosystems could result from differential responses of vegetation and soil processes to changing moisture and temperature regimes and to a lengthening of the growing season. Although shrub expansion and northward movement of treeline should increase carbon inputs, the effects of these vegetation changes on net carbon exchange have not been evaluated. We selected low shrub, tall shrub, and forest tundra sites near treeline in northwestern Alaska, representing the major structural transitions expected in response to warming. In these sites, we measured aboveground net primary production (ANPP) and vegetation and soil carbon and nitrogen pools, and used these data to parameterize the Terrestrial Ecosystem Model. We simulated the response of carbon balance components to air temperature and precipitation trends during 1981–2000. In areas experiencing warmer and dryer conditions, Net Primary Production (NPP) decreased and heterotrophic respiration (R H ) increased, leading to a decrease in Net Ecosystem Production (NEP). In warmer and wetter conditions NPP increased, but the response was exceeded by an increase in R H ; therefore, NEP also decreased. Lastly, in colder and wetter regions, the increase in NPP exceeded a small decline in R H , leading to an increase in NEP. The net effect for the region was a slight gain in ecosystem carbon storage over the 20 year period. This research highlights the potential importance of spatial variability in ecosystem responses to climate change in assessing the response of carbon storage in northern Alaska over the last two decades.  相似文献   

5.
China encourages the demonstration of carbon capture and storage (CCS) projects. In an effort to identify gaps and provide suggestions for environmental risk management of carbon dioxide (CO2) geological storage in China, this article presents a concise overview of potential health, safety and environmental (HSE) risks and environmental management regulations for CO2 geological storage in Australia, Japan, the United States (USA), the European Union (EU), and the United Kingdom (UK). The environmental impact assessment (EIA) experience of Shenhua Ordos Coal-to-Liquid (CTL) Project and PetroChina Jilin Oil Field enhanced oil recovery (EOR) is subsequently analyzed in light of our field investigation, and gaps in current EIA guidelines that are applicable to CO2 geological storage projects are identified. It is found that there are no specific environmental risk regulations suitable for CO2 storage in China, and environmental risk management lags behind the development of CCS technology, which presents a challenge to demonstration enterprises in terms of assessing environmental risk. One major challenge is the overestimation or underestimation of this risk on the part of the enterprise, and another is a lack of applicable regulations for government sectors to supervise the risk throughout CCS projects. Therefore, there is a pressing need for China to formulate environmental management regulations that include environmental risk assessment, mandatory monitoring schemes, environmental emergency plans, and related issues.  相似文献   

6.
滨海湿地碳、氮储量的分布可能受盐沼植被和外源沉积物的综合影响.本文以长江口典型滨海湿地为研究对象,分别在崇明东滩湿地北部、中部和南部设置3条样线,根据外源沉积物的区域特征研究了3种主要盐沼植被(芦苇(Phragmites australis)、互花米草(Spartina alterniflora)、海三棱藨草(Scirpus mariqueter))和土壤中的有机碳(TOC)、总氮(TN)的季节变化及空间特征.结果显示,崇明东滩湿地北、中部为淤积型滩涂,南部呈侵蚀态势.盐沼植被中芦苇和互花米草生物量TOC、TN累积量均显著高于海三棱藨草带.北、中样线的相同植被类型中的土壤TOC、TN显著高于南样线.高潮滩的芦苇带土壤TOC储量高于中潮滩的互花米草带,而互花米草带土壤TN储量略高于芦苇带,海三棱藨草带和光滩土壤TOC、TN储量最低.盐沼植被类型显著影响土壤各层次TOC和TN储量的分布,其中,0~10 cm层次储量受植被类型和表层外源沉积物空间特征的交互作用影响.  相似文献   

7.
There is huge knowledge gap in our understanding of many terrestrial carbon cycle processes. In this paper, we investigate the bounds on terrestrial carbon uptake over India that arises solely due to CO 2 -fertilization. For this purpose, we use a terrestrial carbon cycle model and consider two extreme scenarios: unlimited CO2-fertilization is allowed for the terrestrial vegetation with CO2 concentration level at 735 ppm in one case, and CO2-fertilization is capped at year 1975 levels for another simulation. Our simulations show that, under equilibrium conditions, modeled carbon stocks in natural potential vegetation increase by 17 Gt-C with unlimited fertilization for CO2 levels and climate change corresponding to the end of 21st century but they decline by 5.5 Gt-C if fertilization is limited at 1975 levels of CO2 concentration. The carbon stock changes are dominated by forests. The area covered by natural potential forests increases by about 36% in the unlimited fertilization case but decreases by 15% in the fertilization-capped case. Thus, the assumption regarding CO2-fertilization has the potential to alter the sign of terrestrial carbon uptake over India. Our model simulations also imply that the maximum potential terrestrial sequestration over India, under equilibrium conditions and best case scenario of unlimited CO2-fertilization, is only 18% of the 21st century SRES A2 scenarios emissions from India. The limited uptake potential of the natural potential vegetation suggests that reduction of CO2 emissions and afforestation programs should be top priorities.  相似文献   

8.
以印江槽谷型喀斯特石漠化地区11种植被类型(人工纯林、人工混交林、天然纯林、天然混交林、疏林、竹林、经果林、灌木林、石山地、宜林地、草地)为研究对象,分析了植被碳储量的空间分布格局,并对区域植被固碳速率、碳储量进行了估算,并预测了理论最大固碳潜力。结果表明:印江研究区植被碳储量空间分布为,乔木层(25.06 t/hm2) > 灌木层(3.51 t/hm2) > 草本层(1.10 t/hm2),其平均固碳速率为10.63 t/(hm2·a),植被碳储量为172.23×103 t,植被理论最大固碳潜力为94.02 t/hm2。研究结果对于评价和估计印江槽谷型喀斯特石漠化地区森林的碳汇功能,以及提高碳储量有重要意义。  相似文献   

9.
为阐明施加秸秆及配施生物炭对茉莉花园土壤碳(TC)、氮(TN)、磷(TP)和铁(Fe)含量及其生态化学计量学特征的影响,并探讨土壤活性有机碳及碳库管理指数的响应,以福州茉莉园土壤为研究对象,设置对照、秸秆、秸秆配施生物炭3种处理样地,对施加处理下福州茉莉花园0~10 cm表层土壤碳、氮、磷、铁含量和生态化学计量学特征进行测定和分析.结果表明:不同施加处理下,茉莉园土壤TC、TN含量均值表现为秸秆配施生物炭处理>秸秆处理>对照处理(p<0.05),TP含量均值表现为秸秆处理>秸秆配施生物炭处理>对照处理(p<0.05),土壤Fe含量均值表现为秸秆处理大于对照和秸秆配施生物炭处理,显著增加了茉莉花园表层土壤铁含量(p<0.05).其次,秸秆配施生物炭处理较对照和秸秆处理提高了土壤C/N、C/P、C/Fe、N/P、N/Fe、P/Fe (p<0.05);茉莉花园0~10 cm土壤碳储量、氮储量、磷储量均值表现为秸秆配施生物炭处理显著高于对照处理(p<0.05),提高比例分别为46.5%、20.2%、10.2%,土壤铁储量表现为秸秆处理>对照处理>秸秆配施生物炭处理.此外,秸秆施加处理提高了土壤活性有机碳(CN),增加了土壤碳库活度指数(CPAI)和土壤碳库管理指数(CPMI);秸秆配施生物炭处理同样大幅度提升了土壤总有机碳含量,并显著提高了土壤碳库指数(CPI),但这部分主要是活性较低的稳态碳(CNA),因此,秸秆配施生物炭降低了土壤碳库活度(CPA)、土壤碳库活度指数(CPAI)和土壤碳库管理指数(CPMI).总体来看,从土壤固碳角度考虑,秸秆配施生物炭是更合理的利用措施.  相似文献   

10.
固体废物越境转移是一个国际关注的问题。由于对废物全部无害化处理成本太昂贵,发达国家往往为保护本国环境而向境外转移倾倒。接受固体废物的发展中国家往往沦为被转移国的垃圾场。对此,国际社会以及中国政府都给予了高度关注。目前,中国控制固体废物越境污染转移的法律制度主要建立在《固体废物污染环境防治法》上,大致包括:固体废物的进口管理制度、固体废物处置配套制度、法律责任制度以及救济制度等。但是,现行制度仍然存在缺陷,如调整范围过窄;配套法律制度非常欠缺,缺乏固体废物标准体系;救济方式不足;责任限制不够严厉等。这些不足需要立法进一步完善。  相似文献   

11.
The Regional Greenhouse Gas Initiative for the northeastern states of the U.S. allows for terrestrial carbon (C) sequestration offsets generated by afforestation activities only. This paper estimates the maximum potential quantity and associated costs of increasing the storage of carbon by afforestation of existing agricultural land in the 11 states of the Northeast United States. The focus of the work was to describe location, the quantity, and at what cost it would be economically attractive to shift agricultural production to afforestation to increase carbon storage in the region. Widely available data sets were used to (1) identify spatially-explicit areas for lower costs carbon offsets and (2) estimate carbon supply curves related to afforestation of agricultural land over three time periods (10, 20, and 40 years). Carbon accumulation and total carbon offset project costs were estimated at a county scale and combined to identify expected costs per ton of carbon dioxide equivalents (CO2e). Large variation in estimated costs per ton of CO2e are driven by varying carbon accumulation potentials and opportunity costs of taking land out of agricultural production, as well as the duration of the project activity. Results show that the lowest cost carbon offset projects will be in certain counties of Maine, Vermont, and New York. Pasture land, with lower opportunity costs, generally presents the opportunity for lower cost carbon offset projects relative to cropland. This analysis estimates that afforestation of pasture land in the northeast will not become economically attractive until the price rises above 10 per metric tonne (MT) CO < sub > 2 < /sub > e and that up to 583 million MT could be economically sequestered if the price were to rise to10 per metric tonne (MT) CO2e and that up to 583 million MT could be economically sequestered if the price were to rise to 50 per MT CO2e, based on a 40-year project life. With regard to cropland in the northeast, afforestation does not become economically advantageous for land owners until the price rises above $40 per MT CO2e. It is estimated that up to 487,000 MT could be sequestered from cropland if the price were to rise to $40 per MT CO2e. It is estimated that up to 487,000 MT could be sequestered from cropland if the price were to rise to 50 per MT CO2e, based on a 40-year project life.  相似文献   

12.
Concern about the issue of permanence andreversibility of the effects of carbon sequestrationhas led to the need to devise accounting methods thatquantify the temporal value of storing carbon that hasbeen actively sequestered or removed from theatmosphere, as compared to carbon stored as a resultof activities taken to avoid emissions. This paperdescribes a method for accounting for the atmosphericeffects of sequestration-based land-use projects inrelation to the duration of carbon storage. Firstly,the time period over which sequestered carbon shouldbe stored in order to counteract the radiative forcingeffect of carbon emissions was calculated, based onthe residence time and decay pattern of atmosphericCO2, its Absolute Global Warming Potential. Thistime period was called the equivalence time, andwas calculated to be approximately 55 years. From thisequivalence time, the effect of storage of 1 tCO2 for 1 year was derived, and found to besimilar to preventing the effect of the emission of0.0182 tCO2. Potential applications of thistonne.year figure, here called the equivalencefactor, are then discussed in relation to theestimation of atmospheric benefits over time ofsequestration-based land use projects.  相似文献   

13.
Carbon dioxide (CO2) capture and storage is increasingly being considered as an important climate change mitigation option. This paper explores provisions for including geological CO2 storage in climate policy. The storage capacity of Norway's Continental Shelf is alone sufficient to store a large share of European CO2 emissions for many decades. If CO2 is injected into oil reservoirs there is an additional benefit in terms of enhanced oil recovery. However, there are significant technical and economic challenges, including the large investment in infrastructure required, with related economies of scale properties. Thus CO2 capture, transportation and storage projects are likely to be more economically attractive if developed on a large scale, which could mean involving two or more nations. An additional challenge is the risk of future leakages from storage sites, where the government must take on a major responsibility. In institutional and policy terms, important challenges are the unsettled status of geological CO2 storage as a policy measure in the Kyoto Protocol, lack of relevant reporting and verification procedures, and lack of decisions on how the option should be linked to the flexibility mechanisms under the Kyoto Protocol. In terms of competitiveness with expected prices for CO2 permits under Kyoto Protocol trading, the relatively high costs per tonne of CO2 stored means that geological CO2 storage is primarily of interest where enhanced oil recovery is possible. These shortcomings and uncertainties mean that companies and governments today only have weak incentives to venture into geological CO2 storage.  相似文献   

14.
土壤污染治理与开发的环境经济调控对策研究   总被引:20,自引:5,他引:15  
尝试从环境经济角度出发,对比分析国内外土壤污染治理与开发过程中的经济责任认定体系,指出我国存在着土壤污染责任主体不明确、污染治理费用无人负担、市场化机制有待完善等问题,提出在土壤污染治理与开发过程中明确政府、污染者、新地块开发商以及当地社区和居民的经济责任、建立污染治理基金管理模式以及完善土壤污染治理资金筹措与管理机制等方面的调控对策。  相似文献   

15.
生态补偿是通过经济手段促进生态保护与受益地区利益共享的制度设计,是促进我国生态文明建设的重要举措。秦岭是我国重点生态功能区,国家重要的生态安全屏障。生态补偿作为协调秦岭地区生态环境保护和社会经济发展的制度安排,有助于推动该区生态环境的保护与可持续利用,对实现秦岭地区社会经济可持续发展、促进人与自然和谐共生具有重要意义。本文系统梳理了秦岭生态补偿相关理论研究与实践,主要包括秦岭在区域调水、森林生态效益、生物多样性保护、矿产资源开发等方面的生态补偿研究,以及秦岭生态补偿相关政策法规制定、南水北调、退耕还林(草)以及生态移民搬迁等具体生态保护工程补偿实践,并从补偿对象、补偿标准、公众参与、补偿方式几个角度探讨了秦岭生态补偿存在的问题,提出了秦岭生态补偿研究的建议与对策。  相似文献   

16.
杨奇丽  郭景 《地球与环境》2016,44(4):441-446
采用GC-MS联用系统对三个兰州市典型湿地的沉积物生物标志物——正构烷烃的组成进行了测定,分析了湿地沉积物中正构烷烃组成特征并探讨了其指示的污染源信息。研究结果表明,兰州市湿地沉积物中正构烷烃主要存在高碳数组分奇偶优势显著的单峰型和低碳、高碳组分都有奇偶优势的双峰型两种分布形式;CPI指数分析表明兰州市湿地沉积物中正构烷烃贡献的高碳数部分来源于湿地周围的高等陆生植物,而低碳数部分来源于化石燃料残余。此外,研究发现采石场湿地和银滩湿地公园污染源效应较统一,而雁滩公园污染源受频繁人为活动影响而显示出明显的多元性。  相似文献   

17.
松属(Pinus L.)约113种,是松科现代属中最原始的类群。松属植物种类丰富且研究领域广泛,对其已经积累的资料数据进行系统梳理总结十分必要。本文通过总结国内外松属大化石资料,结合分子系统发育、地质背景和地理隔离事件讨论了其地史分布及植物地理学意义;该属化石在早白垩世至全新世地层中均有记录。化石证据表明松属很可能在早白垩世(之前)起源于西欧地区,从这一起源地通过北大西洋陆桥扩散到北美洲东部,而东亚的类群可能是从北美洲西部经过白令陆桥散布的。在晚白垩世分化出双维管束松亚属Subgenus Pinus L.及单维管束松亚属Subgenus Strobus (D. Don) Lemmon,前者更接近祖先类群。古新世由于全球显著增温以及白垩纪末期大灭绝等地质事件的影响使松属数量急剧减少,在晚始新世至中新世时期随着气温转凉转冷再次分化扩散,中新世达到其发展高峰且分布面貌与现代类群近似。松属多样性时空历史可能和新生代气候变迁及晚新生代构造运动塑造的山地隆升等环境变化紧密相关。  相似文献   

18.
徐自为  张智杰 《环境科学研究》2018,31(11):1909-1917
为全面认识干旱区不同土地利用类型时空变化对区域生态系统碳储量的影响,以地处塔克拉玛干沙漠边缘生态脆弱区的新疆尉犁县为研究对象,基于详细的土地利用变更调查数据(2010-2016年),利用ArcGIS平台和InVEST模型,分析生态系统碳储量对土地利用变化尤其是二级土地利用类型变化的响应.结果表明:①研究区内,无论是区域平均碳密度还是灌木林地、其他林地、其他草地等主要土地利用类型的碳密度均较低,而面积较少的有林地和天然牧草地碳密度相对较高,因此对这些土地利用类型应着重加强保护.②2010-2016年新疆尉犁县碳存储量净减少24.23×104 t,这主要是由于其他草地、其他园地和果园等土地利用类型被开垦为水浇地,或被建设用地、交通用地占用所导致,而同时研究区内有林地和水浇地面积增加带来了碳储量的提高.③从空间变化看,受不同区域土地利用变化方式的影响,碳储量变化特征也有显著差异,但总体上变化敏感区域集中在塔里木河周边县、乡镇及兵团所在地等人类活动聚集区,这些区域平均碳密度较高,土地利用变化也更为剧烈.④尽管由于开垦行为带来耕地面积增加,从而使得研究区耕地总碳储量增加242.77×104 t,但由于塔里木河沿岸碳密度较高的耕地被建设用地占用,新增耕地多来源于土壤碳储量较低的其他草地等土地利用类型,导致耕地平均碳密度有所下降.研究显示,建设用地占用耕地、林地、草地等地类是尉犁县碳储量减少的重要原因,而林业建设能够带来碳储量增加.因此建议:一方面,推进林、草地建设提高区域生态系统固碳能力;另一方面,重点保护塔里木河周边碳密度较高区域,严控耕地开垦或建设用地占用,同时加强耕地保护,防止通过补充碳密度较低的耕地来弥补碳密度较高区域耕地的流失.   相似文献   

19.
根据主体特征,将污染转嫁分为涉外污染转嫁和内部污染转嫁。其法律责任包括行政责任,民事责任和刑事责任。分别就这三种责任的构成要件及责任分担,作了具体分析,并提出了作者的见解。  相似文献   

20.
李楠  刘盈  王震 《环境科学学报》2020,40(2):707-715
产品碳足迹以碳标签的形式日益广泛地应用于产品供应链,通过影响企业和消费者行为而有效地促进全球碳减排.然而产品碳足迹核算标准种类繁多,不同标准对产品碳足迹的核算规定存在差异,致使其核算结果难于有效对比.本文以胶版印刷纸为例,对比分析了目前最权威的3个国际标准PAS2050、GHG Protocol和ISO14067,识别了三者对于8点产品碳足迹核算要素的不同规定,定量解析了标准差异对产品碳足迹核算的影响.结果表明,3个标准规定的差异可导致产品碳足迹核算结果产生较大的不确定性,GHG Protocol和ISO14067结果分别比PAS2050高61%和49%,其中,"碳存储、消费者交通、固定资产和延迟排放加权影响"4个方面的差异对案例产品碳足迹影响最为显著.因此,按照产品类别制定统一的核算要求是碳标签交流对比的基本前提,明晰的标准规定是降低核算结果不确定性的必要途径.  相似文献   

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