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31.
湿地是自然界中重要的“碳汇”,其碳储量变化对全球气候变化和温室效应有重要的影响.选择地理位置独特的黑龙江兴凯湖自然保护区作为研究区,根据保护区内不同土壤类型采集表层(0~20 cm)土壤样品,利用遥感解译的保护区土地利用图、土壤储碳量和植物固碳量计算公式,核算兴凯湖自然保护区生态系统固碳服务总量,同时借鉴瑞典碳税法和中国造林成本法,估算兴凯湖保护区固碳服务功能价值为4.9亿元.结果显示,兴凯湖自然保护区湿地固碳服务功能高于全国平均水平,且高于同纬度同属东北平原的莫莫格湿地,为保护区今后的保护管理策略提供了有效的参考依据.  相似文献   
32.
The karst mountain areas of Southwest China contain barren farmland soils and suffer from nutritional and water deficiencies that affect crop productivity. Hence,it is imperative to apply suitable fertilizers to restore soil fertility and maintain crop yield. The aim of this study is to investigate the effects of mineral-organic fertilizer(MOF)made of potassic rock and organic waste on the growth of crops. For this purpose, green Chinese cabbage grown using three different fertilization methods including MOF,inorganic fertilizer(IF), and a control was evaluated. We determined soil water content, agronomic characteristics,and biomass of green Chinese cabbage in different treatments. Furthermore, surface runoff from the pot experiments and soil leachate from pot experiments were collected to determine water temperature, pH, and cation and anion concentrations. The results demonstrate thatMOF can improve the soil water-holding capacity of soil,and the basic agronomic characteristics of the cabbage treated with MOF were superior to those with IF. Using MOF can promote the increase in cabbage biomass.Additionally, the concentration of inorganic carbon(largely in the form of HCO_3^-) in surface runoff water treated by MOF was higher than the other treatments, establishing carbon sequestration potential. This work provides a novel and environmentally friendly fertilization pattern in karst areas, which will improve crop yield and also increase the carbon sequestration potential of crops.  相似文献   
33.
松辽盆地是中国主要的能源基地,随着中国振兴东北老工业基地政策的实施,如何应对工业和经济发展带来的CO_2排放量的增加,将成为亟需解决的问题。在盆地内进行CO_2地质储存将成为盆地内解决该问题的主要技术选择之一。以松辽盆地为研究对象,在深入分析松辽盆地CO_2地质储存条件的基础上,从储存规模、储存安全性和社会环境风险及经济适宜性4个方面综合考虑,构建了由16个指标组成的松辽盆地CO_2地质储存适宜性评价指标体系,利用灰色关联分析法对松辽盆地33个二级构造单元进行了盆地级适宜性评价工作,评价结果为进一步场地级目标靶区的筛选提供了科技支撑。  相似文献   
34.
We present a numerical study for 3D time‐lapse electromagnetic monitoring of a fictitious CO2 sequestration using the geometry of a real geological site and a suite of suitable electromagnetic methods with different source/receiver configurations and different sensitivity patterns. All available geological information is processed and directly implemented into the computational domain, which is discretized by unstructured tetrahedral grids. We thus demonstrate the performance capability of our numerical simulation techniques. The scenario considers a CO2 injection in approximately 1100 m depth. The expected changes in conductivity were inferred from preceding laboratory measurements. A resistive anomaly is caused within the conductive brines of the undisturbed reservoir horizon. The resistive nature of the anomaly is enhanced by the CO2 dissolution regime, which prevails in the high‐salinity environment. Due to the physicochemical properties of CO2, the affected portion of the subsurface is laterally widespread but very thin. We combine controlled‐source electromagnetics, borehole transient electromagnetics, and the direct‐current resistivity method to perform a virtual experiment with the aim of scrutinizing a set of source/receiver configurations with respect to coverage, resolution, and detectability of the anomalous CO2 plume prior to the field survey. Our simulation studies are carried out using the 3D codes developed in our working group. They are all based on linear and higher order Lagrange and Nédélec finite‐element formulations on unstructured grids, providing the necessary flexibility with respect to the complex real‐world geometry. We provide different strategies for addressing the accuracy of numerical simulations in the case of arbitrary structures. The presented computations demonstrate the expected great advantage of positioning transmitters or receivers close to the target. For direct‐current geoelectrics, 50% change in electric potential may be detected even at the Earth's surface. Monitoring with inductive methods is also promising. For a well‐positioned surface transmitter, more than 10% difference in the vertical electric field is predicted for a receiver located 200 m above the target. Our borehole transient electromagnetics results demonstrate that traditional transient electromagnetics with a vertical magnetic dipole source is not well suited for monitoring a thin horizontal resistive target. This is due to the mainly horizontal current system, which is induced by a vertical magnetic dipole.  相似文献   
35.
本文以贵州省东南部三州为研究区,运用连续生物量转换因子法和平均生物量法,通过2010年森林清查小班数据,建立了24类优势树种的森林植被碳密度与林龄之间的关系。同时,估算了1990-2010年间贵州省东南部森林植被生物量及其碳蓄积量,分析了碳蓄积量的时空变化特征,并预测出2050年该区域森林植被的固碳潜力。结果显示:(1)2010年贵州省东南部森林植被碳蓄积量为106.22 TgC,占贵州省森林植被碳蓄积量的63.01%,占全国森林植被碳蓄积量的1.36%;平均碳密度32.44 MgC/hm2,是贵州省森林植被平均碳密度的93%,全国森林植被平均碳密度的76%,碳密度空间分布呈现由西部向东部增加趋势且东部高于平均水平。(2)1990-2000年间森林植被碳蓄积量增加了30.67 TgC;2000-2010年间森林植被碳蓄积量增加了49.55 TgC,其中,退耕还林导致森林植被碳蓄积量增加了31.09 TgC。(3)以2010年为基准年,假设40 a后贵州省东南部森林面积保持稳定,且不考虑轮伐期的未来情景下,至2050年该区域森林植被碳蓄积量将达到153.38 TgC,其增量可达47.16 TgC,表明贵州省东南部森林具有较大的碳增汇潜力。  相似文献   
36.
Time‐lapse seismic analysis is utilized in CO2 geosequestration to verify the CO2 containment within a reservoir. A major risk associated with geosequestration is a possible leakage of CO2 from the storage formation into overlaying formations. To mitigate this risk, the deployment of carbon capture and storage projects requires fast and reliable detection of relatively small volumes of CO2 outside the storage formation. To do this, it is necessary to predict typical seepage scenarios and improve subsurface seepage detection methods. In this work we present a technique for CO2 monitoring based on the detection of diffracted waves in time‐lapse seismic data. In the case of CO2 seepage, the migrating plume might form small secondary accumulations that would produce diffracted, rather than reflected waves. From time‐lapse data analysis, we are able to separate the diffracted waves from the predominant reflections in order to image the small CO2 plumes. To explore possibilities to detect relatively small amounts of CO2, we performed synthetic time‐lapse seismic modelling based on the Cooperative Research Centre for Greenhouse Gas Technologies (CO2CRC) Otway project data. The detection method is based on defining the CO2 location by measuring the coherency of the signal along diffraction offset‐traveltime curves. The technique is applied to a time‐lapse stacked section using a stacking velocity to construct offset‐traveltime curves. Given the amount of noise found in the surface seismic data, the predicted minimum detectable amount of CO2 is 1000–2000 tonnes. This method was also applied to real data obtained from a time‐lapse seismic physical model. The use of diffractions rather than reflections for monitoring small amounts of CO2 can enhance the capability of subsurface monitoring in CO2 geosequestration projects.  相似文献   
37.
山东半岛蓝色经济区土壤有机碳储量及固碳潜力分析   总被引:1,自引:0,他引:1  
土壤碳储量研究在碳循环和全球变化中具有重要意义,但以往碳储量计算结果受到数据来源的制约。山东省多目标区域地球化学调查采用双层网格化采样和分析,获取了大密度、高精度土壤有机碳数据,为土壤碳库的准确计算奠定了基础。笔者利用这些数据计算了山东半岛蓝色经济区表层(0~20 cm)、中上层(0~100 cm)及全层(0~160 cm)的土壤有机碳(SOC)密度和储量,并对其空间分布特征及固碳潜力进行了研究。结果显示,经济区内3种土壤层次的碳库组成不同,表层SOC储量占总碳(TC)储量的71.67%,随深度增加所占比例逐渐减小,而无机碳(SIC)储量所占比例逐渐增加,全层二者所占比率较为接近:表层SOC储量为132.64 Mt,碳密度为2.06 kg/m2;中上层为458.27 Mt,碳密度为7.11 kg/m2;全层为619.96 Mt,碳密度为9.61 kg/m2。各层SOC密度处于全国偏低水平,且在不同土壤类型、地貌类型、土地利用类型之间有一定差异:褐土土表层SOC密度最高(2.48 kg/m2),风沙土最低(0.91 kg/m2);灌溉水田表层SOC密度最高(3.45 kg/m2),菜地最低(1.61 kg/m2)。表层SOC密度分布总体上呈现为沿海地区低、鲁北平原和胶莱盆地中等、山地丘陵和中低山区偏高的分布格局。从第二次土壤普查和本次多目标调查数据所建立的回归方程分析发现,在今后一定时期内,本区表层土壤总体表现为“碳汇”效应,未来可净增总有机碳(TOC)量60.94 Mt,其中“碳源”量5.07 Mt,“碳汇”量65.97 Mt。  相似文献   
38.
The ecological consequences of grassland afforestation in arid/semiarid sandy regions are not well known with respect to tree species and stand age. The present study quantifies the changes in above- and belowground carbon (C) stocks following afforestation in the southeastern Keerqin Sandy Lands with species of Mongolian pine and poplar. We studied 15-, 24-, and 30-year-old Mongolian pine plantations, 7-, 11-, and 15-year-old poplar plantations, and adjacent grasslands. The results show that total ecosystem C stocks increased following grassland afforestation. Aboveground C stocks increased at a rate of 2.75 Mg C ha−1 yr−1 in the poplar plantations, and 1.06 Mg C ha−1 yr−1 in the Mongolian pine plantations. Mineral soil C stocks decreased during the early stage of forest establishment, but recovered with increasing stand age. Root C stock increased significantly in the Mongolian pine plantations, but the poplar plantations showed no such increase relative to the grassland. Our results indicate that afforestation of the grassland in the southeastern Keerqin Sandy Lands would sequester more C than would continuous grassland. Tree species selection and stand developmental age should be considered in planning future afforestation projects.  相似文献   
39.
地理国情普查成果应用实践与探索   总被引:1,自引:0,他引:1  
分析了地理国情普查和监测的内涵、意义及其成果、产品,并针对当前的热点问题,对地理国情普查成果的应用进行了探索,为确立测绘地理信息部门新的发展方向奠定了良好的研究基础。  相似文献   
40.
土壤作为陆地生态系统的重要组成部分,土壤碳储量研究在全球碳循环变化中意义重大。利用山东省多目标区域地球化学调查(2003年)获得的双层网格化大密度、高精度土壤有机碳(SOC)含量数据,估算了全省0~20 cm、0~100 cm及0~160 cm的土壤碳密度和储量,并对SOC密度和储量的时空变化规律及土壤固碳潜力进行研究。结果表明:(1)山东省0~20 cm、0~100 cm和0~160 cm土层SOC密度分别为222 kg/m2、764 kg/m2、1009 kg/m2,各土层SOC密度均明显低于全国平均水平(319 kg/m2、1164 kg/m2和1534 kg/m2);(2)0~20 cm表层SOC密度分布总体呈现为沿海地区低,鲁西北平原、鲁东丘陵中等,鲁中南山区偏高的分布格局;(3)与18年前第二次土壤普查(1985年)数据对比,表层SOC密度从143 kg/m2升高到222 kg/m2,全省陆域(1570万km2)0~20 cm表层SOC储量则由22641 Mt增加至35065 Mt,净增了12424 Mt,SOC密度以0044 kg/(m2·a)的平均速率在土壤中积累,整体表现为“碳汇”效应;据估算,尚有50523 Mt的固碳潜力。  相似文献   
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