人工林碳汇潜力新概念及应用

定量确定森林碳汇潜力有助于科学地评估森林对碳汇的潜在贡献及制定实现这种潜力所需要的经营管理措施。目前,国内外有关森林碳汇潜力缺乏统一的概念及计量方法。在综述国内外有关固碳潜力概念的基础上,引入时间动态构架和可持续性的概念,提出了针对人工林的固碳潜力概念并利用FORECAST模型以杉木人工林为例阐明此概念的实际意义与应用。     

An oriC-like distribution of GATC sites mediates full sequestration of non-origin sequences in Escherichia coli

Sequestration of newly replicated origins is one of the mechanisms required to limit initiation of Escherichia coli chromosome replication to once per generation. Origin sequestration lasts for a considerably longer period of time than the sequestration of other newly replicated regions of the chromosome. The reason for this may be the high number of GATC sites present in the origin. Alternatively, other sequence elements in the origin region may be important for its prolonged sequestration. To distinguish between these possibilities we constructed a DNA fragment containing ten GATC sites distributed with the same spacing as the ten GATC sites in the left half of oriC, but with random sequence between the GATC sites, and inserted it at a non-sequestered chromosome location. Sequestration of this GATC-cluster lasted as long as that of oriC, or even longer. The result shows that the presence of ten GATC sites, distributed as in oriC, is sufficient to cause full sequestration, and that other sequence elements most likely do not contribute to sequestration.     

农林复合系统固碳潜力研究进展

农林复合系统是解决当前资源枯竭、农林用地紧张和实现环境保护的一种可持续土壤管理模式。自《京都议定书》签订以来, 农林复合系统因其较高的固碳潜力引起了科学家的广泛关注。深入理解农林复合系统的固碳过程及其对气候变化、环境条件的改变和管理措施的响应, 是准确地预测农林复合系统在全球变化情景下固碳潜力的关键。该文综述了农林复合系统的概念和分类, 探讨了农林复合系统相比单一系统的固碳潜力及固碳机理, 分析了农林复合系统固碳潜力的测定方法和当前面临的挑战, 综述了气候因子、环境条件和人为管理措施对农林复合系统固碳潜力的影响。我国农林复合系统的固碳潜力相比全球其他区域还处于较低水平, 为提高我国农林复合系统的固碳潜力, 未来需要加强以下四个方面的工作: 扩大农林复合系统的分布面积、加强农林复合系统的合理配置和管理、选择适宜的物种组合和优化系统的群体结构。     

农田土壤固碳措施的温室气体泄漏和净减排潜力

农田土壤固碳措施作为京都议定书认可的大气CO2减排途径受到了广泛关注.研究表明,农田土壤固碳措施在主要农业国家和全球都具有很大的固碳潜力.但是,实施农田土壤固碳措施有可能影响农业中化石燃料消耗和其他农业投入的CO2排放和非CO2温室气体排放.这些土壤碳库以外的温室气体排放变化可能抵消部分甚至全部土壤固碳效果,构成了农田土壤固碳措施的温室气体泄漏.因此,将土壤固碳和温室气体泄漏综合计算的净减排潜力成为了判定土壤固碳措施可行性的首要标准.综述总结了目前较受重视的一些农田措施(包括施用化学氮肥、免耕和保护性耕作、灌溉、秸秆还田、施用禽畜粪便以及污灌)的土壤固碳潜力,温室气体泄漏和净减排潜力研究成果.结果表明,温室气体泄漏可抵消以上措施土壤固碳效益的-241%～660%.建议在今后的研究中,应该关注土壤碳饱和、气候变化及土地利用变化对农田固碳措施温室气体泄漏和净减排潜力的评估结果的影响.     

Amino acid control of autophagic sequestration and protein degradation in isolated rat hepatocytes

Sequestration of the inert cytosolic marker [14C]sucrose by sedimentable organelles was measured in isolated rat hepatocytes made transiently permeable to sucrose by means of electropermeabilization. Lysosomal integrity, protein degradation, autophagic sequestration, and other cellular functions were not significantly impaired by the electric treatment. Hepatocytes sequestered sucrose at an initial rate of approximately 10%/h, which is threefold higher than the estimated rate of autophagic-lysosomal protein degradation. Almost one-third would appear to represent mitochondrial fluid uptake; the rest was nearly completely and specifically inhibited by 3-methyladenine (3MA) and can be regarded as autophagic sequestration. A complete amino acid mixture was somewhat less inhibitory than 3MA, and partially antagonized the effect of the latter. This paradoxical effect, taken together with the high sequestration rate, may suggest heterogeneity as well as selectivity in autophagic sequestration. There was no detectable recycling of sequestered [14C]sucrose between organelles and cytosol. Studies of individual amino acids revealed histidine as the most effective sequestration inhibitor. Leucine may have a regulatory function, as indicated by its unique additive/synergistic effect, and a combination of Leu + His was as effective as the complete amino acid mixture. Asparagine inhibited sequestration only 20%, i.e., its very strong effect on overall (long-lived) protein degradation must partially be due to post-sequestrational inhibition. The lysosomal (amine-sensitive) degradation of short-lived protein was incompletely inhibited by 3MA, indicating a contribution from nonautophagic processes like crinophagy and endocytic membrane influx. The ability of an amino acid mixture to specifically antagonize the inhibition of short-lived protein degradation by AsN + GIN (but not by 3MA) may suggest complex amino acid interactions at the level of fusion between lysosomes and other vesicles in addition to the equally complex interactions at the level of autophagic sequestration.     

Sequestration in Plasmodium falciparum malaria: sticky cells and sticky problems

Plasmodium falciparum is unique among the human malarias in displaying the phenomenon of sequestration, in which mature infected erythrocytes adhere to post-capillary and capillary venular endothelium. In this review, Tony Berendt, David Ferguson and Chris Newbold describe the molecular and cellular biology of sequestration and cytoadherence. Potential host receptors identified to date that are expressed on endothelial cells (CD36, thrombospondin and ICAM-1) and the parasite-mediated changes in the infected erythrocyte (knob formation, senescence and the expression of parasite-derived neoantigens) are considered as well as the relevance of sequestration as a virulence factor in human disease and its potential role in parasite biology.     

Long‐term organic carbon sequestration in tidal marsh sediments is dominated by old‐aged allochthonous inputs in a macrotidal estuary

Tidal marshes are vegetated coastal ecosystems that are often considered as hotspots of atmospheric CO₂ sequestration. Although large amounts of organic carbon (OC) are indeed being deposited on tidal marshes, there is no direct link between high OC deposition rates and high OC sequestration rates due to two main reasons. First, the deposited OC may become rapidly decomposed once it is buried and, second, a significant part of preserved OC may be allochthonous OC that has been sequestered elsewhere. In this study we aimed to identify the mechanisms controlling long‐term OC sequestration in tidal marsh sediments along an estuarine salinity gradient (Scheldt estuary, Belgium and the Netherlands). Analyses of deposited sediments have shown that OC deposited during tidal inundations is up to millennia old. This allochthonous OC is the main component of OC that is effectively preserved in these sediments, as indicated by the low radiocarbon content of buried OC. Furthermore, OC fractionation showed that autochthonous OC is decomposed on a decadal timescale in saltmarsh sediments, while in freshwater marsh sediments locally produced biomass is more efficiently preserved after burial. Our results show that long‐term OC sequestration is decoupled from local biomass production in the studied tidal marsh sediments. This implies that OC sequestration rates are greatly overestimated when they are calculated based on short‐term OC deposition rates, which are controlled by labile autochthonous OC inputs. Moreover, as allochthonous OC is not sequestered in‐situ, it does not contribute to active atmospheric CO₂ sequestration in these ecosystems. A correct assessment of the contribution of allochthonous OC to the total sedimentary OC stock in tidal marsh sediments as well as a correct understanding of the long‐term fate of locally produced OC are both necessary to avoid overestimations of the rate of in‐situ atmospheric CO₂ sequestration in tidal marsh sediments.     

Prediction of the effect of immunoglobulin therapy in ITP

The correlation between the response to high-dose immunoglobulin therapy (IVIg) and the sequestration pattern of Indium-labeled platelets (In-PLT) in the body was studied in 9 patients with chronic idiopathic thrombocytopenic purpura (ITP). Patients that has prominent platelet sequestration in the spleen responded to IVIg. In these patients, splenic sequestration decreased by 20-30% after IVIg without significant changes in hepatic sequestration. This finding suggests that the blocking of splenic Fc receptors with immunoglobulin minimized the destruction of sensitized platelets. However, patients who had almost equal platelet sequestration in the liver and spleen did not respond to IVIg. In these patients, hepatic sequestration decreased after IVIg, whereas splenic sequestration increased. Thus, it appears that estimating the platelet sequestration pattern using In-PLT is useful for predicting the effects of IVIg.     

The carboxyl terminus of the hamster beta-adrenergic receptor expressed in mouse L cells is not required for receptor sequestration

The structural basis for agonist-mediated sequestration and desensitization of the beta-adrenergic receptor (beta AR) was examined by oligonucleotide-directed mutagenesis of the hamster beta AR gene and expression of the mutant genes in mouse L cells. Treatment of these cells with the agonist isoproterenol corresponded to a desensitization of beta AR activity. A mutant receptor that bound agonist but did not couple to adenylate cyclase showed a dramatically reduced sequestration response to agonist stimulation. In contrast, beta AR mutants in which the C-terminus was truncated and/or in which two regions that have been proposed as phosphorylation substrates for cAMP-dependent protein kinase were removed showed normal sequestration responses. These results demonstrate that agonist-mediated sequestration of the beta AR can occur in the absence of the C-terminus of the protein and reveal a strong correlation between effective coupling to Gs and sequestration.     

Determination of intracellular organelles implicated in daunorubicin cytoplasmic sequestration in multidrug-resistant MCF-7 cells using fluorescence microscopy image analysis

BACKGROUND: Anthracycline resistance is known to be mediated by P-glycoprotein (P-gp) or multidrug-resistance related protein (MRP) as well as intracellular sequestration of drugs. METHODS: The resistance phenotype of doxorubicin-selected MCF-7(DXR) human breast adenocarcinoma cell line was characterized by cellular and nuclear daunorubicin efflux, P-gp and MRP expression and apoptosis induction. Daunorubicin sequestration was investigated through organelle markers (lysosomes, endoplasmic reticulum and Golgi apparatus) and daunorubicin co-localization by dual-color image analysis fluorescence microscopy using high numerical aperture objective lenses to achieve the smallest field depth and the best lateral resolution. Signal to noise and specificity ratios were optimized for daunorubicin and organelle fluorescent probes labeling. RESULTS: An original image analysis procedure was developed to investigate daunorubicin and organelles co-localization. The reliability of the image analysis was controlled through chromatic shift and intensity linearity measurement using calibrated microbeads. The main contribution (65%) of Golgi vesicles in daunorubicin sequestration was demonstrated. Although no rational relationship could be established between daunorubicin sequestration and apoptosis induction, no apoptosis was observed in MCF-7(DXR) cells. CONCLUSIONS: In addition to P-glycoprotein mediated drug efflux and without MRP overexpression, MCF-7(DXR) daunorubicin resistance phenotype involves drug sequestration within intracellular vesicles identified as Golgi vesicles and resistance to apoptosis induction.     

1990-2030年中国主要陆地生态系统碳固定服务时空变化

以中国森林、草地、湿地等主要陆地生态系统为研究对象,估算了植被和土壤有机碳固定量现状与近20年生态系统碳固定变化量,预测了未来20年3种不同社会经济发展情景下主要陆地生态系统的碳固定潜力,评估了我国主要陆地生态系统碳固定服务的现状、过去变化及未来潜力。结果表明：（1）2010年,中国主要陆地生态系统碳固定总量达17.29PgC,其中植被碳固定量8.70PgC,30cm深度土壤有机碳固定量8.59PgC。其中,森林碳固定量占73.26%,草地占21.55%,湿地占5.18%。（2）1990-2000年,我国主要陆地生态系统碳固定总量减少了2.15%,其中森林、草地和湿地分别减少了1.12%、0.97%、20.19%。2000-2010年,碳固定总量增加了2.92%,其中森林增加了3.72%,草地和湿地分别减少了0.62%和5.59%。（3）前、后两个10年相比,碳固定总量从轻微下降转变为轻微上升趋势。其中,森林碳固定量从下降趋势转变为上升趋势,说明生态工程成效明显。草地碳固定量处于基本持衡态势,碳固定减少量和减少比例有所下降,湿地碳固定量的下降趋势亦有所缓解,说明草地退化、湿地破坏趋势有所遏制,但仍需要重点关注。（4）至2030年,3种社会经济发展情景下,我国主要陆地生态系统碳固定总量将呈现较明显的上升态势,增量可达430.11-498.06TgC,增加比例5.15-5.97%,以森林碳固定量增加为主,而草地碳固定服务呈现微弱减少态势。     

Carbon Sequestration in Reclaimed Minesoils

Minesoils are drastically influenced by anthropogenic activities. They are characterized by low soil organic matter (SOM) content, low fertility, and poor physicochemical and biological properties, limiting their quality, capability, and functions. Reclamation of these soils has potential for resequestering some of the C lost and mitigating CO₂ emissions. Soil organic carbon (SOC) sequestration rates in minesoils are high in the first 20 to 30 years after reclamation in the top 15 cm soil depth. In general, higher rates of SOC sequestration are observed for minesoils under pasture and grassland management than under forest land use. Observed rates of SOC sequestration are 0.3 to 1.85 Mg C ha^{? 1} yr^{? 1} for pastures and rangelands, and 0.2 to 1.64 Mg C ha^{? 1} yr^{? 1} for forest land use. Proper reclamation and postreclamation management may enhance SOC sequestration and add to the economic value of the mined sites. Management practices that may enhance SOC sequestration include increasing vegetative cover by deep-rooted perennial vegetation and afforestation, improving soil fertility, and alleviation of physical, chemical and biological limitations by fertilizers and soil amendments such as biosolids, manure, coal combustion by-products, and mulches. Soil and water conservation are important to SOC sequestration. The potential of SOC sequestration in minesoils of the US is estimated to be 1.28 Tg C yr^?1, compared to the emissions from coal combustion of 506 Tg C yr^{? 1}.     

河南封丘县域农田土壤固碳速率空间变异特征及其影响因素

农田土壤固碳速率是评价土壤固碳效应和潜力的重要指标,精确估算区域农田土壤固碳速率对土壤地力及环境效应均具有重要意义.本研究选取黄淮海平原典型潮土区河南省封丘县为研究区域,按照土壤利用-土壤类型联合单元布点法,于2011年采集了70个耕层土样,测定了土壤有机碳含量、机械组成、容重、pH,并与全国第二次土壤普查(1981年)数据进行对比分析,结合地统计方法和GIS技术研究了该地区近30年农田土壤固碳速率的空间变异特征,利用显著性检验、回归分析、方差分析等方法定量分析了该区域农田土壤固碳速率的影响因素.结果表明: 近30年封丘县域土壤固碳速率平均值为0.33 t C·hm^-2·a^-1,变异系数为74%,属于中等变异性;土壤固碳速率的变化在东西方向上表现为西高东低、中部高南北低,呈片状分布,区域结构性因素是引起农田土壤固碳速率空间分布差异的主导因素,如土壤类型、机械组成、容重、pH,可解释空间变异的59.5%,其次是随机性因素,如秸秆还田量、施肥量,可解释空间变异的40.5%.     

Vegetation carbon sequestration in Chinese forests from 2010 to 2050

Forests store a large part of the terrestrial vegetation carbon (C) and have high C sequestration potential. Here, we developed a new forest C sequestration (FCS) model based on the secondary succession theory, to estimate vegetation C sequestration capacity in China's forest vegetation. The model used the field measurement data of 3161 forest plots and three future climate scenarios. The results showed that logistic equations provided a good fit for vegetation biomass with forest age in natural and planted forests. The FCS model has been verified with forest biomass data, and model uncertainty is discussed. The increment of vegetation C storage in China's forest vegetation from 2010 to 2050 was estimated as 13.92 Pg C, while the average vegetation C sequestration rate was 0.34 Pg C yr^?1 with a 95% confidence interval of 0.28–0.42 Pg C yr^?1, which differed significantly between forest types. The largest contributor to the increment was deciduous broadleaf forest (37.8%), while the smallest was deciduous needleleaf forest (2.7%). The vegetation C sequestration rate might reach its maximum around 2020, although vegetation C storage increases continually. It is estimated that vegetation C sequestration might offset 6–8% of China's future emissions. Furthermore, there was a significant negative relationship between vegetation C sequestration rate and C emission rate in different provinces of China, suggesting that developed provinces might need to compensate for undeveloped provinces through C trade. Our findings will provide valuable guidelines to policymakers for designing afforestation strategies and forest C trade in China.     

Antigen-specific lymphocyte sequestration in lymphoid organs: lack of essential roles for alphaL and alpha4 integrin-dependent adhesion or Galphai protein-coupled receptor signaling

Selective lymphocyte sequestration was described over 30 years ago as the transient withdrawal of Ag-specific lymphocytes from the circulation as a result of their activation in secondary lymphoid organs. We used a TCR-transgenic adoptive transfer system to further characterize the Ag and adjuvant dependence of this process in mice. In addition, we examined the contribution of the alpha(L) and alpha(4) integrin chains as well as Galpha(i) protein-coupled receptor signaling to the retention of Ag-specific T cells in peripheral lymph nodes. Our results demonstrate that selective lymphocyte sequestration is T cell autonomous and adjuvant independent, and that the duration of sequestration is not controlled by the continued presence of Ag in secondary lymphoid organs. This process is not critically dependent on the alpha(L) and alpha(4) integrin chains or Galpha(i) protein-coupled receptor signaling. Selective lymphocyte sequestration may be mediated by redundant mechanisms and/or controlled by novel or nonclassical adhesion or trafficking molecules.     

The impact of nitrogen deposition on carbon sequestration in European forests and forest soils

An estimate of net carbon (C) pool changes and long‐term C sequestration in trees and soils was made at more than 100 intensively monitored forest plots (level II plots) and scaled up to Europe based on data for more than 6000 forested plots in a systematic 16 km × 16 km grid (level I plots). C pool changes in trees at the level II plots were based on repeated forest growth surveys At the level I plots, an estimate of the mean annual C pool changes was derived from stand age and available site quality characteristics. C sequestration, being equal to the long‐term C pool changes accounting for CO₂ emissions because of harvest and forest fires, was assumed 33% of the overall C pool changes by growth. C sequestration in the soil were based on calculated nitrogen (N) retention (N deposition minus net N uptake minus N leaching) rates in soils, multiplied by the C/N ratio of the forest soils, using measured data only (level II plots) or a combination of measurements and model calculations (level I plots). Net C sequestration by forests in Europe (both trees and soil) was estimated at 0.117 Gton yr^?1, with the C sequestration in stem wood being approximately four times as high (0.094 Gton yr^?1) as the C sequestration in the soil (0.023 Gton yr^?1). The European average impact of an additional N input on the net C sequestration was estimated at approximately 25 kg C kg^?1 N for both tree wood and soil. The contribution of an average additional N deposition on European forests of 2.8 kg ha^?1 yr^?1 in the period 1960–2000 was estimated at 0.0118 Gton yr^?1, being equal to 10% of the net C sequestration in both trees and soil in that period (0.117 Gton yr^?1). The C sequestration in trees increased from Northern to Central Europe, whereas the C sequestration in soil was high in Central Europe and low in Northern and Southern Europe. The result of this study implies that the impact of forest management on tree growth is most important in explaining the C pool changes in European forests.     

草原固碳量估算方法及其敏感性分析

 通过提高草地管理水平来增加草地生态系统的碳储量, 是一种低成本的固碳减排途径。固碳量的确定是固碳成本估算中的重要组成部分, 目前国际上通用的草地固碳量估算方法有两种: 碳储量变化法和碳通量法。该文以禁牧为固碳措施, 通过敏感性分析讨论了这两种方法对草原固碳成本估算的适宜性。结论得出: 在一定牧压强度范围和一定面积研究区内, 固碳成本与牧压强度成线性增长关系, 与研究区面积成非线性关系, 表现出“饱和增长”的趋势; 与碳通量法相比, 碳储量变化法对牧压强度和研究区面积都较不敏感。造成这种差异的主要原因是不同方法选取的研究区及其放牧强度背景不同。从草地生态系统过程看, 碳储量变化法与碳通量法在本质上是一致的, 二者都较适于草原禁牧措施下的固碳量和固碳成本的估算, 可根据获取数据类型的不同而采用不同的方法。     

采伐对豫西退耕还林工程固碳的影响

以豫西退耕还林工程重点县嵩县为研究对象,收集了嵩县2002—2010年退耕还林工程逐年实施的造林面积、树种等数据,利用合适的人工林蓄积量生长方程和和中国退耕还林后的土壤有机碳变化的研究结果,结合各树种的木材密度、生物量扩展因子、碳含量等参数,在采伐和无采伐两种情景模式下对其退耕还林工程在2002—2050年的碳储量及其变化进行估算。结果表明:2010年,工程林总碳储量为0.470 Tg(Tg=10~(12)g),工程实施期间,工程前期碳储量高于后期;土壤有机碳库在2002—2010年期间年固碳量均为负值,表现为碳排放,2011年后土壤年固碳量开始增加;在两种情境模式下,工程林年固碳量最高峰都在2015年,2033年以后采伐情景的年固碳量大于无采伐情景。预计到2020、2030、2040和2050年,嵩县退耕还林工程在无采伐情境下的固碳增汇潜力分别为0.760、1.464、1.852和1.985 Tg,在采伐情景下的固碳增汇潜力分别为0.760、1.240、1.657和2.000 Tg,从长时间来看,豫西退耕还林工程林在采伐情景下具有较大的碳汇潜力,因此,对退耕还林工程林实施适度的采伐可以提高工程的碳汇能力。     

黄土丘陵区土壤有机碳固存对退耕还林草的时空响应

研究了黄土丘陵区土壤有机碳固存对退耕还林草的时空响应特征,分析了退耕还林草对土壤有机碳的近期影响和长期效应。结果表明,1)从黄土丘陵区退耕还林草的土壤固碳效应整体而言,相对于坡耕地,退耕还林和退耕撂荒具有显著的土壤碳增汇效应,而退耕还草、退耕还果没有明显土壤碳增汇效应。以天然草地土壤有机碳密度为目标,撂荒地表层土壤有机碳增汇潜力可达8.3 t/hm2。2)以10a为界,退耕还林草的近期土壤碳增汇效应不明显,而10a后土壤碳增汇效应逐渐明显,退耕还林、还灌、撂荒和坡耕地的固碳效应差异显著。3)在评估黄土丘陵区退耕还林草的土壤固碳效应时应当注重长期固碳效应。4)退耕还林草的土壤固碳效应主要受还林草方式及年限的影响,二者分别可解释55.6%和24.1%的有机碳变异性;地形因子可解释8.5%的有机碳变异性。在评估该区退耕还林的土壤固碳效应时应当充分考虑退耕年限和地形因子的影响。5)人工刺槐林地、人工柠条林地以及撂荒地深层土壤(100—200 cm)有机碳密度占2 m土体有机碳密度的35%—40%,而且随着植被恢复深层土壤有机碳密度显著增加。6)在估算黄土丘陵区退耕还林土壤固碳效应时应该考虑深层碳累积。如果按1 m土层的土壤有机碳密度计算,会严重低估退耕还林草的土壤固碳量。     

Trends and scenarios of the carbon budget in postagricultural Puerto Rico (1936–2060)

Contrary to the general trend in the tropics, Puerto Rico underwent a process of agriculture abandonment during the second half of the 20th century as a consequence of socioeconomic changes toward urbanization and industrialization. Using data on land‐use change, biomass accumulation in secondary forests, and ratios between gross domestic product (GDP) and carbon emissions, we developed a model of the carbon budget for Puerto Rico between 1936 and 2060. As a consequence of land abandonment, forests have expanded rapidly since 1950, achieving the highest sequestration rates between 1980 and 1990. Regardless of future scenarios of demography and land use, sequestration rates will decrease in the future because biomass accumulation decreases with forest age and there is little agricultural land remaining to be abandoned. Due to high per‐capita consumption and population density, carbon emissions of Puerto Rico have increased dramatically and exceeded carbon sequestration during the second half of the 20th century. Although Puerto Rico had the highest percent of reforestation for a tropical country, emissions during the period 1950–2000 were approximately 3.5 times higher than sequestration, and current annual emission is almost nine times the rate of sequestration. Additionally, while sequestration will decrease over the next six decades, current socioeconomic trends suggest increasing emissions unless there are significant changes in energy technology or consumption patterns. In conclusion, socioeconomic changes leading to urbanization and industrialization in tropical countries may promote high rates of carbon sequestration during the decades following land abandonment. Initial high rates of carbon sequestration can balance emissions of developing countries with low emission/GDP ratio. In Puerto Rico, the socioeconomic changes that promoted reforestation also promoted high‐energy consumption, and resulted in a net increase in carbon emissions.