我国草地的固碳功能

本文通过综述当前我国草地碳库的研究成果,并利用1982—2011年的遥感影像,估算出我国草地生态系统碳库约为31.2 Pg C,其中96%储存于土壤中。由于我国草地类型多样,分布地域广阔,造成草地植被碳密度分布的空间异质性很高。内蒙古是草地植被碳库最大的省份,其次是西藏和青海,六大牧区的植被碳库占全国草地植被碳库总量的71%。然而,我国90%的天然草地发生不同程度的退化,采取有效的人工管理措施和实施重大的生态建设工程,均对草地碳库的恢复具有明显的作用,说明我国草地有很大的碳汇潜力。     

我国主要农作物生产碳汇结构现状与优化途径

大气中温室气体浓度的增加引起的全球气候变化成为威胁人类生存和发展的一大难题。农作物的碳汇功能对气候变化也起着重要的调节作用。农作物的生产过程既是碳源也是碳汇。本文收集整理分析了我国主要农作物农作系统的相关碳排放参数,估算了农田碳汇碳源效应及其动态变化特征,对作物生产系统的碳投入产出进行定量评价。为我国发展低碳农业规划、政策制定提供了依据,并提出了我国农田碳汇结构的优化途径。     

舰艇水下噪声分析的多输入／输出模型的等效源方法

本文在多用输出／输出模型研究舰艇噪声源贡献的基础上提出了等效源法，当输入等较大时，采用等效源法可使输入数减小，且答等效输入相互独立、传递函数为１、输出自谱是各等效输入自谱之和。，给出了划分等效输入的方法及计算等效输入自谱的公式。     

草地生态系统服务经济价值评估研究

草地是我国面积第二大的陆地生态系统，生态系统服务功能突出，但蕴含的经济价值和相应实现机制有待深入研究。本文基于现有文献，系统评估了全球和中国的草地生态系统服务经济价值与时空变动规律，完成了部分主要生态价值的实证研究。结果表明，全球草地生态服务价值年均为2.19×10¹³美元，相当于2020年全球国内生产总值(GDP)的16.4%；中国草地年均生态服务价值为6.22×10¹²元(相当于2020年GDP的6.13%或农业GDP的80%)，其中草地生态调节功能占比为84%，集中在西藏、内蒙、新疆、青海等省份；生态服务经济价值随着经济发展而不断提高。研究发现，草地生态系统在旅游文化、防沙固沙等方面的潜在经济价值相比已有文献结果更高，但实现相应价值面临诸多挑战。文章提出了提升和实现草地生态服务经济价值的发展战略、试点示范工程、保障措施等建议，以期为该领域发展及实践研究提供参考。     

新形势下发展草地农业保障食物安全的战略思考

在居民膳食结构转型、全球极端天气频发、国际地缘冲突加剧的新形势下，树立大食物观、重视并发挥草地的食物供给功能是提升我国食物安全保障能力和水平的重要依托，因而探讨发展草地农业以保障我国食物安全成为亟需。本文以定性、定量分析相结合的方式，讨论了新形势下发展草地农业的重要价值，阐述了典型国家草地农业发展态势以及对我国的发展启示，进一步测算了我国草地农业对食物安全的贡献潜力。研究认为，天然草原的优质畜产品供给潜力较大，草地农业可强化传统农区食物安全保障功能，农牧交错区将是草食家畜产品的主要生产基地，南方地区是草地农业发展的优势地区。为此建议：加大牧区草原修复力度，合理利用长期禁牧草原；将饲草作为重要作物，加强草类植物育种；发展放牧型栽培草地，缓解天然草地生产压力；优化养殖业结构，发展节粮型草食家畜养殖业；因地制宜“藏粮于草”，增强草地食物供给能力。     

新型数字矩阵处理器SC64

数字矩阵处理器SC64拥有64个通道的模拟输入／输出,从SC64处理器的面板显示可以清楚地看到那个通道是模拟音频信号输入或是模拟音频信号输出,也还可以查看到该通道是数字音频信号输入或数字音频信号输出,详见下图1。这种64通道的输入／输出安排成8个组（A、B、C、D、E、F、G、H组）,每组有8个输入／输出接口槽,通过这些接口槽容易构建出种种不同的负载结构,模拟输入接口槽能接纳带有Mic／Line开关选择和可提供需要幻像电源的宽带音频信号源。另外,本机还设有两个高速传输选择接口槽,用于将来的高速宽带音频信号的输入／输出传输。所有这些结构都安装在标准2U型的机架内。     

碳包Ni纳米晶的形成及其特性

用直流碳弧法制备出碳包Ni金属纳米晶.在石墨阳极复合棒中掺入不同组份的Ni，研究其对碳包Ni纳米晶，富勒烯等碳微团特性的影响结果表明：碳包Ni纳米晶含Ni和石墨，不含碳化物和氧化物；纳米品数量随Ni增加而增加．而纳米晶的粒径出现极值；Ni催化碳微团石墨化并使C60／70产率下降；碳包Ni金属纳米晶单位质量的饱和磁化强度随Ni的增加而增加     

秦巴山脉区域生态系统服务重要性评价及生态安全格局构建

秦巴山脉地区生态系统的生态安全格局对维护我国中部地区生态系统结构健康、控制生态过程起着关键性的作用,构建合理的生态安全格局是保障该地区生态安全的有效措施。本研究在对秦巴山脉地区水源涵养、物种多样性、生态固碳和土壤保持服务功能重要性评估的基础上,根据这四项生态服务功能在生态资产价值中所占比重赋予权重,结合生态系统敏感性分析结果,采用景观生态的源汇理论,利用热点分析工具识别秦巴山脉地区生态源地。运用最小累积阻力模型识别潜在生态廊道,在此基础上结合区域内河流水系、关键物种分布特征、自然保护区分布等要素形成带状生态廊道和踏脚石生态廊道;最终形成由6大重要生态斑块、10条河流廊道、2条生物通道,以及26处踏脚石廊道组成的秦巴山脉地区生态安全格局。基于生态系统服务功能重要性的生态安全格局构建,是在生态服务现状基础上提出的规划策略,可为秦巴山脉地区国家公园规划布局,区域生态保护规划和生态文明建设提供重要依据。     

FOXPRO2．6中数组的应用

本文从以下八个方面对ＦＯＸＰＲＯ２．６在数组的扩充应用方面做了详细的研究和介绍：输入和修改记录；数据库内记录的移动和复制；修改库结构；生成菜单列表选项；获得目录和文件信息；数组的排序和查找；数据的计算；多用户下数据更新的检查。使得数组的应用跳出了原来的狭小范围，功能大大加强     

当前我国碳汇林业发展探究

随着国民经济的快速增长，二氧化碳的排放量也逐渐增加，主要是由消耗化石燃料引起的。二氧化碳的增加，影响着气候的变化，使得一些地方出现极端天气、随着全球气温的上升，海平面也不断攀升等。森林可以吸收二氧化碳，缓解全球气候变暧。因此，增加森林碳汇成为应对气候变化的一种有效措施。本文在阐述有关碳汇林业的相关理论之外，还对我国发展碳汇林业的意义进行了分析，并从多个方面介绍了我国目前碳汇林业的发展，并结合了我国的实际情况，就我国碳汇林业的发展提出了一些可行性的建议。     

基于统计数据郑州市全口径碳汇估算研究

由于地处华北平原,郑州市域内农田面积较多,约占44.40％,而森林和城市绿化面积相对较少.目前,我国的碳汇主要估算对象是林业资源,常常忽略了农田和城市绿化碳汇资源.为全面了解郑州市全口径碳汇情况,利用郑州市的统计数据,估算了郑州市森林碳汇(乔木林、竹林、经济林、灌木林等)、农田碳汇(小麦、玉米、蔬菜、瓜果等)和城市绿化...     

福州市PM2.5中碳组分的污染特征研究

于2015年3月-2016年1月在福州市八个点位采集春夏秋冬四个季节的大气细颗粒物PM_2.5样品,共861个,采用热光反射法测定了PM_2.5中的含碳物质OC、EC,探讨OC、EC的浓度水平、季节变化、相关性、OC/EC的比值以及二次有机碳(SOC)的分布特征。结果表明,福州市大气PM_2.5中OC的浓度范围为(6.2~10.8)μg/m3,EC的浓度范围为(2.0~4.1)μg/m3,总碳TC在PM_2.5中所占的比例范围为(28.7~34.6)%。各点位中OC、EC的季节变化特征为春>冬>秋>夏。OC/EC的比值均大于2.0左右,说明各点位PM_2.5中存在二次有机碳。运用OC/EC最小比值法对SOC的含量进行估算,SOC年平均浓度为3.8μg/m3,占OC含量的46.8%。SOC对PM_2.5的贡献率春、冬季比夏、秋季高,这可能与夏季温度高、光照强烈有利于光化学反应进行有关。夏、秋、冬三个季节OC与EC的相关性较好,春季OC与EC的相关性差,说明夏秋冬三季节OC与EC的来源相同,春季OC与EC来源相对复杂。OC和EC中不同温度段的碳组分构成和TC与K+的相关性分析表明汽油车尾气排放、燃煤排放、生物质燃烧是福州大气碳质组分的主要来源。     

The aesthetics of water and land: a promising concept for managing scarce water resources under climate change

The eastern Mediterranean faces a severe water crisis: water supply decreases due to climate change, while demand increases due to rapid population growth. The GLOWA Jordan River project generates science-based management strategies for maximizing water productivity under global climate change. We use a novel definition of water productivity as the full range of services provided by landscapes per unit blue (surface) and green (in plants and soil) water. Our combined results from climatological, ecological, economic and hydrological studies suggest that, in Israel, certain landscapes provide high returns as ecosystem services for little input of additional blue water. Specifically, cultural services such as recreation may by far exceed that of food production. Interestingly, some highly valued landscapes (e.g. rangeland) appear resistant to climate change, making them an ideal candidate for adaptive land management. Vice versa, expanding irrigated agriculture is unlikely to be sustainable under global climate change. We advocate the inclusion of a large range of ecosystem services into integrated land and water resources management. The focus on cultural services and integration of irrigation demand will lead to entirely different but productive water and land allocation schemes that may be suitable for withstanding the problems caused by climate change.     

A catchment-scale carbon and greenhouse gas budget of a subarctic landscape

This is the first attempt to budget average current annual carbon (C) and associated greenhouse gas (GHG) exchanges and transfers in a subarctic landscape, the Lake Tornetr?sk catchment in northern Sweden. This is a heterogeneous area consisting of almost 4000 km2 of mixed heath, birch and pine forest, and mires, lakes and alpine ecosystems. The magnitudes of atmospheric exchange of carbon in the form of the GHGs, CO2 and CH4 in these various ecosystems differ significantly, ranging from little or no flux in barren ecosystems over a small CO2 sink function and low rates of CH4 exchange in the heaths to significant CO2 uptake in the forests and also large emissions of CH4 from the mires and small lakes. The overall catchment budget, given the size distribution of the individual ecosystem types and a first approximation of run-off as dissolved organic carbon, reveals a landscape currently with a significant sink capacity for atmospheric CO2. This sink capacity is, however, extremely sensitive to environmental changes, particularly those that affect the birch forest ecosystem. Climatic drying or wetting and episodic events such as insect outbreaks may cause significant changes in the sink function. Changes in the sources of CH4 through increased permafrost melting may also easily change the sign of the current radiative forcing, due to the stronger impact per gram of CH4 relative to CO2. Hence, to access impacts on climate, the atmospheric C balance alone has to be weighed in a radiative forcing perspective. When considering the emissions of CH4 from the mires and lakes as CO2 equivalents, the Tornetr?sk catchment is currently a smaller sink of radiative forcing, but it can still be estimated as representing the equivalent of approximately 14000 average Swedish inhabitants' emissions of CO2. This can be compared with the carbon emissions of less than 200 people who live permanently in the catchment, although this comparison disregards substantial emissions from the non-Swedish tourism and transportation activities.     

裂解温度,裂解时间和原料气流量对CVD法生产碳纳米管的影响

用ＣＶＤ法生产碳纳米管时，裂解温度、裂解时间和原料气流量大小对碳纳米管的产率、形态有很大影响，其中以裂解温度的影响最大。适宜的裂解温度、裂解时间和原料气流量有利于提高碳纳米管的产率和产量。在一定范围内提高裂解温度，可得到缺陷较少的碳纳米管     

The carbon balance of Africa: synthesis of recent research studies

The African continent contributes one of the largest uncertainties to the global CO(2) budget, because very few long-term measurements are carried out in this region. The contribution of Africa to the global carbon cycle is characterized by its low fossil fuel emissions, a rapidly increasing population causing cropland expansion, and degradation and deforestation risk to extensive dryland and savannah ecosystems and to tropical forests in Central Africa. A synthesis of the carbon balance of African ecosystems is provided at different scales, including observations of land-atmosphere CO(2) flux and soil carbon and biomass carbon stocks. A review of the most recent estimates of the net long-term carbon balance of African ecosystems is provided, including losses from fire disturbance, based upon observations, giving a sink of the order of 0.2 Pg C yr(-1) with a large uncertainty around this number. By comparison, fossil fuel emissions are only of the order of 0.2 Pg C yr(-1) and land-use emissions are of the order of 0.24 Pg C yr(-1). The sources of year-to-year variations in the ecosystem carbon-balance are also discussed. Recommendations for the deployment of a coordinated carbon-monitoring system for African ecosystems are given.     

一种新型储氢材料─纳米炭纤维的制备及其储氢特性

利用气相流动催化法和高压容积法对纳米炭纤维的大量制备及其储氢特性进行了研究　结果表明,利用在小型装置上优化的制备工艺参数,在反应空间扩大７倍的中型装置中可以实现纳米炭纤维的大量制备　在制备过程中加入扰流管能够改变炉管中的气流状态,从而影响纳米炭纤维的直径和产率　扰流管放置在适宜的区域,能够得到直径较细、纯净、碳源转化率达３０％的纳米炭纤维　实验发现纳米炭纤维的表面处理是影响其储氢性能的主要因素,经过适当表面处理的纳米炭纤维,其储氢容量达到 １０％     

Carbon in the atmosphere and terrestrial biosphere in the 21st century

The release of carbon dioxide from fossil-fuel combustion and land-use change has caused a significant perturbation in the natural cycling of carbon between land, atmosphere and oceans. Understanding and managing the effects of this disruption on atmospheric composition and global climate are likely to be amongst the most pressing issues of the 21st century. However, the present-day carbon cycle is still poorly understood. One remarkable feature is that an increasing amount of atmospheric carbon dioxide appears to be being absorbed by terrestrial vegetation. I review the recent evidence for the magnitude and spatial distribution of this 'terrestrial carbon sink', drawing on current research on the global atmospheric distribution and transport of carbon dioxide, oxygen and their isotopes; direct measurement of CO(2) fluxes above various biomes; and inventories of forest biomass and composition. I review the likely causes of these carbon sinks and sources and their implications for the ecology and stability of these biomes. Finally, I examine prospects and key issues over coming decades. Within a few years, satellite measurements of atmospheric CO(2) and forest biomass, coupled with 'real-time' biosphere-atmosphere models, will revolutionize our understanding of the terrestrial carbon cycle. Controlling deforestation and managing forests has the potential to play a significant but limited part in reaching the goal of stabilizing atmospheric CO(2) concentrations. However, there are likely to be limits to the amount of carbon storage possible in natural vegetation, and, in the long term, terrestrial carbon storage may be unstable, with the potential to accelerate rather than brake global warming.