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961.
洪湖湿地大气调节价值评价研究   总被引:3,自引:3,他引:0  
以洪湖湿地为研究对象,基于现有研究资料对其大气调节服务价值进行了定量评价。结果表明:洪湖湿地大气调节服务总价值为254.52×106元/a,是过去研究结果的11.6倍,其中湿地植物净固定的温室气体价值(包含甲烷折算的排放价值)为58.50×106元/a,表现为较强的碳汇;湿地释放氧气价值为176.51×106元/a,增湿调温价值为19.51×106元/a。洪湖湿地植被净固定温室气体价值、释放氧气价值和增湿调温价值分别占大气调节服务总价值的22.98%、69.35%和7.7%。  相似文献   
962.
基于野外监测数据和碳税法对辽宁双台河口芦苇湿地的固碳价值进行了定量评价。结果表明:辽宁双台河口芦苇湿地总面积为30 815 hm~2,大约占到了自然保护区总面积的20%,其年均净固定二氧化碳(CO_2)量为13 320 kg/hm~2,年甲烷(CH_4)排放的CO_2当量为3 330.3kg/hm~2。将芦苇湿地固定CO_2的正效应减去CH_4排放的负效应,得到辽宁双台河口芦苇湿地的年固碳量为9 989.7 kg CO_2/hm~2,具有较强的碳汇,其总固碳价值为2.37亿元,其中净吸收CO_2的价值为3.16亿元(正效应价值),净排放CH_4的价值为0.79亿元(负效应价值)。  相似文献   
963.
自然环境溶解有机碳(DOC)的组成影响着微生物群落结构,不同微生物类群对有机碳源类型的利用表现出差异。然而,纯菌株的碳源利用选择性及其和盐度的关系却仍不是很清楚。本文采用单碳源纯培养技术、聚合酶链式反应(PCR,Polymerase Chain Reaction)和相关统计方法,研究了青藏高原北部六个湖泊(洱海、青海湖、托素湖、尕海1、尕海2、小柴旦湖)沉积物中的基于不同碳源可培养细菌多样性及其与盐度的响应关系。采用七种不同类型的单碳源(甲酸钠、乙酸钠、丙酮酸钠、乳酸钠、葡萄糖、纤维素、混合氨基酸)进行培养筛选。本文共获得10个细菌分类属,它们分属于假单胞菌属(Pseudomonas)、气单胞菌属(Aeromonas)、希瓦氏菌属(Shewanella)、脱氯单胞菌属(Dechloromonas)、动性球菌属(Planococcus)、盐单胞菌属(Halomonas)、微小杆菌属(Exiguobacterium)、弧菌属(Vibrio)、交替假单胞菌属(Pseudoalteromonas)和芽孢杆菌属(Bacillus)。其中,盐单胞菌属菌株可利用本研究使用的所有碳源类型,说明这类细菌具有广泛碳代谢途径,并潜在地参与了青藏高原北部湖泊碳循环过程。所得的纯菌株利用不同碳链长度的碳源具有选择性,即随着盐度增高,某些菌株更偏向利用结构更加复杂的碳源。总之,盐度不仅影响着纯培养细菌群落多样性,而且还影响着细菌对碳源类型的选择。  相似文献   
964.
黑潮主流径海域海水中的无机碳及其对东海陆架区的影响   总被引:3,自引:2,他引:1  
基于2014年5—6月对黑潮主流径及毗邻东海陆架海区的调查,研究了该区域水体中无机碳体系参数(p H、总碱度TAlk、溶解无机碳DIC及DIC/TAlk)的垂直与水平分布,在此基础上定量评估了黑潮输入对东海陆架海区无机碳收支的影响。结果表明,黑潮水体中DIC、TAlk与DIC/TAlk总体而言随水深增加而升高,p H降低,综合体现了浮游植物生产、海-气界面交换、有机物降解及Ca CO3溶解等过程的影响;上升流中心站位无机碳参数均受较深层水体上涌影响,与黑潮主流径其它站位略有不同。东海陆架海区外侧站位表层、30m层无机碳主要受台湾海峡暖流影响,高p H、低DIC/TAlk的黑潮表层水影响区域局限于东南部;而在底层,低p H、高DIC/TAlk的黑潮入侵流离开黑潮主流径向正北方延伸并抬升至钱塘江口附近;上升流对无机碳的影响持续至表层,其携带的黑潮中层水因此也可能进入陆架海区。水量模型估算黑潮水在5—10月间跨域陆架边缘向东海陆架区输入溶解无机碳总计58798.9×109mol,净输入达37382.9×109mol,而东海向外输出的无机碳绝大部分经由对马海峡进入日本海。  相似文献   
965.
The compositions, distribution and its interaction with rocks of the evolving pore fluids controls the distribution of carbonate cements and reservoir storage spaces. The reservoir quality of the red-bed sandstone reservoirs in the Dongying Depression was investigated by an integrated and systematic analysis including carbonate cement petrology, mineralogy, carbon and oxygen isotope ratios and fluid inclusions. The investigation was also facilitated by probing the mineral origins, precipitation mechanisms, pore fluid evolution and distribution, and water-rock interaction of carbonate cements and their influences on reservoir quality. Diagenetic-evolving fluids in the interbedded mudstones are the main source for the precipitation of calcite cements that completely fill the intergranular volume (CFIV calcite) with heavier oxygen and carbon isotopes. The ferro-carbonate cements in the reservoir sandstone are enriched in lighter carbon and oxygen isotopes. In addition to the cations released by the conversion of clay minerals in reservoirs, products of organic acid decarboxylation and the associated feldspar dissolution process provide important sources for such carbonate cementation. The carbon isotopes of CO2 and the oxygen isotopic composition of fluids equilibrated with the CFIV calcite, ferro-calcite, dolomite and ankerite cements indicate that the pore in the red-bed reservoirs experienced high salinity fluids, which evolved from the early-formed interbedded mudstones, through organic acid input and to organic acid decarboxylation. Pore fluids from nearby mudstones migrated from the edge to the centre of sandbodies, causing strong calcite cementation along the sandbody boundaries and forming tight cementation zones. Pore fluids associated with organic CO2 and acids and organic acid decarboxylation are mainly distributed in the internal portion of sandbodies, causing feldspar dissolution and precipitation of ferro-carbonate cements. The distribution of pore fluids caused the zonal distribution of carbonate cements in sandbodies during different periods. This may be advantageous to preserve the porosity of reservoirs as exemplified by the distribution of high-quality reservoirs in the red-bed sandbodies.  相似文献   
966.
The emissions reduction pledges made by individual countries through the 2015 Paris Agreement represent the current global commitment to mitigate greenhouse gas emissions in the face of the enduring climate crisis. Natural lands carbon sequestration and storage are critical for successful pathways to global decarbonization (i.e., as a negative emissions technology). Coastal vegetated habitats maintain carbon sequestration rates exceeding forest sequestration rates on a per unit area basis by nearly two orders of magnitude. These blue carbon habitats and their associated carbon sequestration benefits are vulnerable to losses from land-use change and sea-level rise. Incorporation of blue carbon habitats in climate change policy is one strategy for both maintaining these habitats and conserving significant carbon sequestration capabilities. Previous policy assessments have found the potential for incorporation of coastal carbon sequestration in national-level policies, yet there has – to date – been little inclusion of blue carbon in the national-scale implementation of Paris commitments. Recently, sub-national jurisdictions have gained attention as models for pathways to decarbonization. However, few previous studies have examined sub-national level policy opportunities for operationalizing blue carbon into climate decision-making. California is uniquely poised to integrate benefits from blue carbon into its coastal planning and management and its suite of climate mitigation policies. Here, we evaluated legal authorities and policy contexts addressing sequestration specifically from blue carbon habitats. We synthesized the progressive action in California’s approaches to mitigate carbon emissions including statutory, regulatory, and non-regulatory opportunities to incorporate blue carbon ecosystem service information into state- and local-level management decisions. To illustrate how actionable blue carbon information can be produced for use in decision-making, we conducted a spatial analysis of blue carbon sequestration in several locations in California across multiple agencies and management contexts. We found that the average market values of carbon sequestration services in 2100 ranged from $7,730 to $44,000 per hectare and that the social cost of carbon sequestration value was 1.3 to 2.7 times the market value. We also demonstrated that restoration of small areas with high sequestration rates can be comparable to the sequestration of existing marshes. Our results illustrate how accessible information about carbon sequestration in coastal habitats can be directly incorporated into existing policy frameworks at the sub-national scale. The incorporation of blue carbon sequestration benefits into sub-national climate policies can serve as a model for the development of future policy approaches for negative emissions technologies, with consequences for the success of the Paris Agreement and science-based decarbonization by mid-century.  相似文献   
967.
2011年以来,我国碳排放权交易市场建设不断加快,碳排放权交易机制不断健全完善,其中基准线法被确定为全国碳交易初始配额分配的主要方法。电解铝行业是我国能源消耗和碳排放的重点部门,尽早将该行业纳入碳市场对于行业减排、纵深推进全国碳市场交易以及应对国际碳边境调节机制政策均有重要意义。基于2018年电解铝行业直报的碳排放相关数据,确定了我国电解铝行业开展全国碳交易的基准线方案。结果显示,电解铝行业宜选取8.12~8.15 t CO2/t铝作为基准线取值,不需设置区域差异调整系数。同时为保证电解铝行业碳交易的顺利开展,还需尽快确定行业配额方案,进一步完善企业排放量的监测、报告和核查以提高核查填报数据质量,以及进一步研究电解铝行业碳排放核算的范围。  相似文献   
968.
Voluntary offsetting of flight-related emissions is an important cornerstone of passengers’ individual efforts to contribute to climate change mitigation. Hence, many scientific studies have tried to assess people’s willingness-to-pay to offset their own flight-related carbon emissions. Up-to-date, these studies are overwhelmingly grounded in hypothetical stated-preference approaches, with very limited knowledge about external validity. Here, we report on an observational field study involving a final sample of 63,520 bookings made with a European airline, allowing us to gauge actual willingness-to-pay for carbon dioxide compensation in a revealed-preference approach. Our pre-registered study shows that the median willingness-to-pay to voluntarily offset a ton of carbon dioxide from flight-related emissions is zero, with the mean willingness-to-pay being around 1 EUR. Aggregated voluntary willingness-to-pay thus dramatically falls short of current prices to offset carbon dioxide, for example through the EU-ETS. Our results thereby question the suitability of self-reported, hypothetical assessments of offsetting and raise caution about the effectiveness of offsetting schemes, which currently do not very successfully internalize flight-related cost of emissions.  相似文献   
969.
As a hard-to-abate sector, the iron and steel industry is responsible for 22% of China’s total carbon emissions and therefore plays a crucial role in achieving China’s carbon peaking and neutrality target. Nearly 90% of China’s iron and steel output is produced with coal-based blast furnaces, which results in high carbon emission intensity. To peak China’s carbon emissions and achieve the carbon neutrality target, it is essential to accelerate the application of breakthrough technologies such as carbon capture and storage (CCS) and hydrogen-based steel-making. This paper estimates the future CO2 emissions from China’s iron and steel industry in pathways that consider the influence of different technology portfolios, technology maturity, decarbonization of power systems, and future steel production output. The results show that using currently available technology, China’s iron and steel industry can reduce CO2 emissions by more than 50%. However, it cannot achieve the neutrality target without using innovative technologies. By combining conventional strategies with net-zero emission technologies such as CCS and hydrogen metallurgy, approximately 80–90% emission reduction can be achieved, thus leading to a carbon neutrality pathway, which can meet the 1.5°C targets of the carbon budget limit either. In the future, carbon emissions' reduction potential will be influenced by the decarbonization of power systems and the diffusion rate of innovative technologies. To achieve carbon neutrality, it is essential to act sooner and faster.  相似文献   
970.
Carbon removal – also known as negative emissions technologies, or greenhouse gas removal – represents a core pillar of post-Paris climate policy, signaling for enhancing and constructing carbon sinks to balance emissions sources on route to ambitious temperature targets. We build on Amory Lovins’ “hard” and “soft” alternatives for energy pathways to illuminate how foundational experts, technologists, and policy entrepreneurs think about different modes of resource inputs, infrastructure and livelihoods, and decision-making, regarding ten nature-based and engineered carbon removal approaches. Based on 90 original interviews, we show that hard and soft paths reflect different conceptions of systems, spaces, and societal involvement. We highlight that pathways depend on diverging concepts of economies-of-scale (capturing carbon at the largest possible scale, versus catalyzing systemic co-benefits) and carbon management (a waste product within conventional climate governance, versus diverse end-uses and values to be diversely governed). Our analysis further emphasizes two key uncertainties: whether renewables can be upscaled to allow synergies rather than tradeoffs between carbon removal and more widespread energy demands, and whether carbon certification can expand spatially to navigate long supply chains, and conceptually to incentivize diverse co-benefits. Experts remain motivated by antecedent concerns over land-use management and extractive industries, and that exploitative systems will – without guardrails – be replicated by inertia.  相似文献   
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