Introduction:Climate warming-induced extreme drought has led to substantial growth decline and extensive tree mortality in forests worldwide, with such phenomena being particularly pronounced in plantation ecosystems. This study aimed to assess the divergent climatic responses of radial growth between healthy and declining Simon poplar (Populus simonii Carr.) plantations. Methods:Separate ring-width chronologies were developed for healthy (1996-2024 period) and declining (1994-2024 period) Simon poplar plantations in the Engebei Ecological Demonstration Zone of Ordos, to explore their differing responses to climate factors. Results:All statistical parameters of the declining chronologies were higher than those of the healthy ones, indicating that the declining chronologies exhibited higher quality and stronger common signals, whereas the healthy chronologies were comparatively weaker. Climate-growth response analyses revealed that radial increments of declining trees displayed significantly greater sensitivity to climatic variability than healthy trees, while the basal area increment showed the opposite pattern-declining trees had markedly lower climatic sensitivity than healthy individuals. As Simon poplar trees enter the growth decline phase, drought stress exerts increasingly strong suppressive effects on radial growth, while the warming-induced stimulation of basal area increment becomes progressively weaker. Discussion:The divergent responses of radial growth and basal area increment to climate variability underscore the key climatic determinants shaping the decline of poplar plantations across the study area. Overall, this study contributes to a mechanistic understanding of climate-driven growth decline in poplar plantations of the Ordos area and provides a scientific basis for ecological restoration and sustainable management of local degraded plantations.

The rapid identification and quantitative detection of pesticides on a portable device is of vital importance for food safety evaluation and human health protection. However, conventional strategies for realizing the reliable, portable and sensitive detection of target analytes are still challenging. In this work, the ordered polymethyl methacrylate (PMMA) microspheres array were employed as template to fabricate PMMA@Ti3C2Tx. Silver nanoparticles (AgNPs) were then uniformly immobilized onto the composite substrate through an in-situ route, generating abundant electromagnetic hotspots. Benefiting from the synergistic electromagnetic and chemical enhancement, a high-performance PMMA@Ti3C2Tx-Ag composite array SERS substrate was successfully fabricated. The prepared array substrate exhibits excellent SERS performance with good uniformity (relative standard deviation, RSD < 5%) and satisfactory stability. It achieves the detection concentration of 10-9 M for probe molecules of crystal violet (CV) and 4-aminothiophenol (4-ATP). For pesticide detection, the substrate realizes trace detection of diquat and triazophos at 10-8 M, while the detection concentration for thiram is 10-7 M. Taking advantage of the unique molecular fingerprint signature of SERS, the platform enables simultaneous identification of various pesticide molecules. Further practical tests were carried out to perform in-situ analysis of pesticide residues on the surfaces of blueberries and cherry tomatoes. The detectable concentrations of target pesticides are well below the maximum residue limits stipulated by the European Union, demonstrating the great potential of the SERS platform for rapid screening applications in food safety monitoring. These results indicate the promising potential of the sensing platform for rapid on-site monitoring of pesticide residues in complex food matrices.

Urbanization drives habitat loss and fragmentation, posing serious threats to biodiversity. Butterfly is a key bioindicator taxon for assessing urban ecosystem health. Many studies have investigated the effects of park features and within-park configuration on butterfly diversity separately. However, their relative importance and potential interactions remain poorly understood. We address this issue based on field-based butterfly surveys with landscape pattern metrics, focusing on the urban parks within the fifth Ring Road of Beijing. We found at the park level, park size was positively correlated only with total abundance, showing no significant association with richness or the Shannon-Wiener index. In contrast, the perimeter-area ratio (PARA) showed a significantly negative correlation with both richness and the Shannon-Wiener index. The within-park configuration also significantly affects butterfly diversity. The mean patch size (AREA_AM) was positively correlated with all three diversity indices, and the largest patch index (LPI) was a significant predictor of the Shannon-Wiener index. The comparison of the relative importance showed that PARA had a stronger negative effect on richness and the Shannon-Wiener index than within-park configuration metrics, highlighting the critical role of park shape. For total abundance, park size was the only significant predictor. More importantly, a significant interaction was observed between park size and PARA for the Shannon-Wiener index. More specifically, the negative effect of PARA diminished with the increase of park size, indicating that optimizing park shape is particularly effective for enhancing butterfly diversity in small parks, whereas increasing total habitat area in large parks can buffer the negative effects of irregular shapes. These findings provide important insights on urban park management for biodiversity conservation.

The Electron-ion collider in China (EicC) is a proposed future electron-ion collider designed to achieve a high luminosity, with a center-of-mass energy ranging from 15 to 20 GeV. Excellent particle identification (PID) with extensive momentum coverage is essential for investigating exclusive and semi-inclusive processes, as well as enabling precise 3D imaging of the nucleon structure in the EicC experiment. To meet its PID requirement, the EicC Collaboration has proposed the conceptual design of various Cherenkov detectors, including the DIRC in the barrel region and the RICH in the endcap region. It also involving the TOF detector for PID in the low momentum region. The GEANT4 simulation, which integrate advanced optical transmission models and image reconstruction algorithms, have been conducted to study and optimize the performance of these detectors.

Nitrous acid (HONO) is a key precursor of OH radical, initiating daytime photochemistry. But its sources remain highly uncertain, particularly in suburban mountain area affected by urban transport. In summer 2023, intensive observations were conducted at the Mangshan (MS, 659 m) site, located along the prevailing southerly pathway from urban Beijing, with the Institute of Chemistry Chinese Academy of Sciences (ICCAS, 59 m) in the city center as an urban reference. Elevated HONO concentrations were observed at MS (average: 0.42 ± 0.31 ppb; maximum: 1.62 ppb). Multiple lines of evidence demonstrated that high pollutants levels at MS were strongly influenced by emissions from urban area and mountain foot through the “urban-mountain” transport chain and upslope valley winds. Daytime source analysis revealed that NO + OH homogeneous reaction only explained ∼ 7 % of observed HONO, indicating strong additional sources (Pother, average: 0.94 ± 0.42 ppb/h; maximum: 2.35 ppb/h). Photo-enhanced NO2 heterogeneous reactions and nitrate photolysis represented additional sources. The majority of unexplained HONO (∼ 48.7 %) was attributed to transport and secondary formation on transport. HONO photolysis contributed 79.3 % to OH production at MS, higher than 73.6 % at ICCAS and exceeding values at other mountain sites. Overall, Beijing urban emissions significantly enhanced HONO and oxidation capacity in the suburban mountain area through the “urban-mountain” transport chain. This study provides important evidence for understanding pollution transport and oxidation processes under complex terrain, with direct implications for improving regional air quality modeling and formulating targeted pollution control strategies.

Urbanization is accompanied by a series of potential issues, among which the urban heat island (UHI) effect is a major concern. While urban ventilation corridors play a crucial role in addressing the UHI effect and fine particulate matter (PM2.5) pollution, research on the diffusion mechanism of PM2.5-bound compounds are limited, especially those of per- and polyfluoroalkyl substances (PFAS). In this work, we analyze the levels of 67 PFAS in PM2.5 along urban ventilation corridors, and utilize air-mass reaction trajectories to study their transport mechanisms. Overall, 23 PFAS involved in atmospheric transport were identified at meteorological stations. The median ΣPFAS concentration in the cold season (274 pg/m3) was significantly higher than that in the warm season (114 pg/m3), with trifluoroacetic acid (TFA) being the dominant homologue. Emissions from traditional fluorochemical industries and the use of fluorinated alternatives represented the main sources. Interesting, during the cold season (when prevailing northwesterly winds occur), a marked increase in PM2.5-bound PFAS level was measured at the northwest corner. Trajectory models and potential source contribution functions revealed that high-altitude mountainous terrain in the northwest prevents wind from entering the city. Meanwhile, changes in air pressure led to southeasterly winds, which could carry TFA and PM2.5 northwestward along urban ventilation corridors, contributing 24-45% and 35-38% of the total mass, respectively. This study provides the first insight into the impact of urban ventilation corridors on the migration of particulate PFAS, which is of great significance for understanding local PFAS transport, not release, among urban clusters.

IntroductionTree transpiration plays a critical role in water cycling and energy balance, contributing to the regulation of urban microclimates. Rapid urbanization has created pronounced urban–rural environmental differences that can substantially alter tree transpiration and its regulatory mechanisms, yet these effects remain poorly understood.MethodsWe investigated the transpiration patterns of Pinus tabuliformis, a native tree species in Beijing, based on a 10-year dataset (2014-2023) of sap flow and environmental measurements collected from contrasting urban and rural sites. Linear models, piecewise structural equation modeling (piecewise SEM), and boundary line analysis were used to quantify transpiration responses to environmental drivers across contrasting urban and rural conditions, identify environmental thresholds, and assess stomatal regulation strategies under contrasting environmental conditions.ResultsThe results showed that transpiration rates were significantly higher at the urban site, with mean daily rates approximately threefold greater than those at the rural site, and peak transpiration occurring 1.3 h earlier. The responses of transpiration to environmental drivers differed between sites. For example, transpiration increased with vapor pressure deficit (VPD) and plateaued at approximately 1.76 kPa at the urban site, whereas it increased initially but declined beyond a threshold of 1.33 kPa at the rural site. Transpiration at the urban site was primarily driven by photosynthetically active radiation (PAR), indicating energy-limited conditions, whereas at the rural site it was mainly constrained by soil moisture, reflecting water-limited conditions. These differences were associated with contrasting stomatal regulation strategies, with rural trees exhibiting higher sensitivity to VPD (m/gcref = 0.86) and stronger stomatal control under water-limited conditions.DiscussionOur results demonstrate that long-term urban-rural environmental differences reshape transpiration patterns, environmental responses, and stomatal regulation strategies in trees. These findings provide new insights into tree water-use strategies under urbanization and suggest that atmospheric drought and soil water availability jointly regulate transpiration responses across contrasting habitats. Our study also provides key parameters for improving ecohydrological models and urban forest management.

Urban areas are the major anthropogenic source of atmospheric CO2, thus making long-term and continuous observations of their carbon emission dynamics extremely important. The COVID-19 lockdown served as a natural experiment that provided a unique opportunity to analyse the contribution of human activities to CO2 emissions from urban areas. In 2020, Beijing experienced COVID-19 confinement with different levels of restrictions on social mobility and economic activity, resulting in reductions in CO2 emissions. To investigate the response mechanisms of CO2 flux to restriction measures, we analysed CO2 flux data obtained using the eddy covariance technique from 2015 to 2020, and compared CO2 flux during the COVID-19 confinement period in 2020 with the preceding years (2015-2019) and across various levels of confinement. The results showed that: (1) the annual CO2 flux was 2.1 ± 0.2 kg C/(m2·yr) in 2020, which showed a significant reduction of 31.8 % compared to the adjacent 2019; (2) the reduction in CO2 flux was closely related to the level of restrictions on human activities; (3) most reductions occurred during the morning (85.7 %) and evening (32.7 %) peak traffic times, indicating that commuting-related transportation is a primary contributor to urban CO2 emissions. It is suggested that measures that reduce transportation-related CO2 sources should be considered as priorities for reducing urban CO2 emissions. The dynamic variation of urban CO2 flux captured by the eddy covariance technology is conductive to strengthening the supervision of the implementation of urban carbon emission reduction policies, promoting the achievement of dual carbon goals.

Ground-level ozone (O3) pollution has been a severe environmental and health problem for decades. The importance of biogenic volatile organic compounds (BVOCs) in the formation of tropospheric photochemistry O3 has been highlighted, especially in areas of rapid urbanization. We conducted simultaneous measurements of trace gases, including NO, NOX, O3, and BVOCs (i.e., isoprene and α-pinene), in the urban and rural forest areas of Beijing to determine the relationships between them. The results highlight the differences between the urban and rural forest areas of Beijing in terms of ambient air concentrations of BVOCs and O3, and the interrelationships between BVOCs, NOX, and ozone were quantified. Moreover, the isoprene concentration was found to be higher in the atmosphere of the urban site than of the rural site, which had higher α-pinene concentrations and higher O3 concentrations. The NOX concentration was higher at the urban site than at the rural site, and there was a significant exponential relationship between NOX and O3 at the urban site, indicating that the impact of NOx on O3 at the urban site was greater than that at the rural site. The O3 concentration increased with rising isoprene and α-pinene in both sites. In the case of substantially increased BVOC concentrations, declining NOX concentrations strongly promote the formation of O3. Consideration should be given to planting tree species with low-BVOC emissions, as they are crucial for mitigating O3 pollution in urban areas. Additionally, the relationships between BVOCs, NOX, and O3 should be considered in policymaking related to O3 control.

Elemental carbon (EC) and metals are two important parts of atmospheric black carbon (BC). However, little information is available regarding the interaction between them and its impacts on the reactive oxygen species (ROS) formation and physiological antioxidants depletion. In this study, we chose six most frequently detected metals (Cu(Ⅱ), Fe(Ⅲ), Mn(Ⅱ), Cr(Ⅲ), Pb(Ⅱ) and Zn(Ⅱ)) in BC and examined their interactions with EC in the ROS generation and glutathione (GSH) oxidation. Results showed that only Cu(Ⅱ) and EC synergically promoted the GSH oxidation and hydroxyl radical (•OH) generation. Other five metals had negligible effects on the GSH oxidation regardless of the presence or absence of EC. The synergistic interaction between Cu(Ⅱ) and EC could be attributed to the superior electrical conductivity of EC. In the process, EC transferred electrons from the adjacent GSH to Cu(Ⅱ) through its graphitic carbon framework to yield Cu(Ⅰ) and GSH radical. Cu(Ⅰ) further reacted with dioxygen to generate •OH, which eventually led to the oxidation of GSH. Our results revealed a new driving force inducing the ROS formation and GSH depletion as well as provided novel insights into the risk assessment of BC.

Nitrous acid (HONO), a key precursor of hydroxyl radicals (OH), is one of the factors affecting atmospheric chemistry and air quality. Currently, the proposed sources of HONO are not able to fully explain observed HONO concentrations. In this study, a comprehensive field observation of HONO was conducted in the autumn of 2021 in urban Beijing. The box model using a default Master Chemical Mechanism (MCM) was unable to reproduce the observed HONO concentrations with a normalized mean bias (NMB) of −92.8%. The NMB improved to −46.1% after the inclusion of seven additional HONO formation pathways. Several factors like vehicle emission factor (1.23%) and nocturnal NO2 heterogeneous uptake coefficient on the ground surface (8.25 × 10−6) were calculated based on observational data. The enhancement factor for nocturnal NO2 heterogeneous conversion was established as a function of relative humidity (RH) and incorporated into the model, which compensated for the missing nocturnal HONO sources and well-reproduced the observed HONO concentrations, with an NMB of −5.1%. The major source of HONO at night was found to be the heterogeneous reaction of NO2 on the ground surface, contributing up to 85.6%. During the daytime, it was the homogeneous reaction of NO with OH, accounting for 41.8%. The daytime primary source of OH was mainly the photolysis of HONO, which constituted 73.6% and therefore promoted the formation of secondary pollutants and exacerbated haze events.

Carbonyls have an important effect on atmospheric chemistry and human health because of their high electrophilicity. Here, high-throughput screening of carbonyl molecules in complex aerosol samples was achieved by combining targeted derivatization with non-targeted analysis using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Results showed that water-soluble organic matter (WSOM) in PM2.5 contains a large variety of carbonyls (5147 in total), accounting for 17.6 % of all identified organic molecules. Compared with non-carbonyl molecules, carbonyl molecules are more abundant in winter than in summer, and have unique molecular composition and chemical parameters. For the first time, a significant positive correlation was found between the abundance of carbonyl molecules and the dithiothreitol (DTT) activities of WSOM, and the elimination of the carbonyl group remarkably reduced the DTT activities, highlighting the pivotal role of carbonyls in determining the oxidative potential (OP) of organic aerosol. Among various molecules, oxidized aromatic compounds containing the carbonyl group produced in winter contributed more to the enhancement of DTT activity, which could be used as potential markers of atmospheric oxidative stress. This study improves our understanding of the chemical diversity and environmental health effects of atmospheric carbonyls, emphasizing the need for targeted strategies to mitigate the health risks associated with carbonyl-rich aerosols.

The intermittent ozone (O3) exposure of crops to alternating high and low concentrations is common in fields, but its impact on crop production has not been thoroughly investigated. In this study, two widely planted and O3-sensitive crops, winter wheat and soybean, were intermittently exposed to elevated O3 concentrations in open-top chambers. The results showed that the winter wheat and soybean yields significantly decreased with O3 exposure (AOT40, cumulative hourly O3 concentration above 40 ppb) (p < 0.001). The relative yield losses were 0.99% per AOT40 for winter wheat and 1.2% per AOT40 for soybean, respectively. The responses of the crop biomasses to elevated O3 concentrations were lower than that of crop yield. Although the O3-induced crop yield and biomass losses under continuous O3 exposure were greater than those under intermittent O3 exposure, the differences were not statistically significant. Therefore, we can conclude that the effects of elevated O3 concentrations on crops are closely related to the exposure dose but not significantly related to the temporal distribution of elevated O3 concentrations. This study improves our understanding of how crop production responds to intermittent O3 exposure.

The Bohai Sea is one of the most polluted marine areas in China with polycyclic aromatic hydrocarbons (PAHs) due to its unique hydrological and geographical environment. To investigate differences in PAH concentrations, composition, and particle-water partitioning before and after the rainy reason, water samples were collected during two surveying voyages covering most of the area of the Bohai Sea. Total and dissolved PAH concentrations were higher during the June voyage (total PAHs: 32.29 & PLUSMN; 15.18 ng/L, dissolved PAHs: 31.25 & PLUSMN; 15.26 ng/L) than the August voyage (total PAHs: 15.98 & PLUSMN; 6.39 ng/L, dissolved PAHs: 11.21 & PLUSMN; 5.59 ng/L). The opposite trend was observed for particulate PAHs (June: 1.04 & PLUSMN; 1.01 ng/L, August: 4.78 & PLUSMN; 2.96 ng/L). Among particulate PAHs, an unusually high proportion (65.07%) of low-molecular-weight (LMW) PAHs was observed during the August voyage, which was significantly higher than the proportion during the June voyage (21.86%). This high proportion was inconsistent with the general distribution of PAHs in the aquatic environment according to their physicochemical properties. The excess LMW PAHs adsorbed on suspended particulate matter arose mainly from soil affected by the petrochemical industry of the Bohai Economic Rim, and were carried with particles on runoff into the Bohai Sea during the rainy season. An estimated 5.49 t of LMW PAHs transitioned from the particulate phase to the dissolved phase during the rainy season. This transfer of LMW PAHs from coastal soil to the water column may be an important source of PAHs in the Bohai Sea.

城市是人类居住和活动最集中地区,其CO2排放量占世界总排放量的 71％,城市碳排放规律研究对全球碳减排工作具有重要意义.利用涡动相关技术观测了北京市某街区 2015 年至 2016 年的CO2通量,重点研究了不同时间尺度和气象条件下的CO2通量的日变化规律,分析了影响城市CO2通量的社会及自然因素.结果表明,CO2通量日变化特征具有(1)明显的早晚"双峰型"特征,早晚高峰分别出现在早上 7:30-9:30 和晚上 17:30-20:30;(2)周末特征:周末早高峰时间延迟,晚于工作日约1.5h,且峰值低了约 10.8％,但晚高峰时间提前,且峰值高于工作日约 10.6％;(3)季节特征:冬季CO2通量均值和早高峰值明显高于其他季节,夏季中午具有明显低峰区;(4)风向特征:在不同来风方向上,CO2通量的日变化峰值差异很大;(5)天气特征:阴天双峰特征比晴天明显.研究表明CO2通量日变化主要与交通流量动态变化关系最为密切,其次要受到植被的影响.因此,交通减排和植被增汇对于控制城市碳排放具有重要意义.

The natural manipulative experimentꎬ by controlling influencing factors appropriately to study changes in the ecosystem under natural conditionsꎬ has become more and more popular with ecologists. This articleꎬ which focused on the experimental design methods of urban ecology ( such as artificial gradientsꎬ natural gradients and urban construction experiments)ꎬ environmental factors ( such as air pollutionꎬ heat islandsꎬ nightlight and surface hardening) and the response of urban ecosystems (such as communitiesꎬ green spacesꎬ green roofs and watersheds)ꎬ reviewed a great number of cases using natural manipulative experiments in urban ecology at home and abroad. It also summarized the characteristics of the natural manipulative experiment of urban ecologyꎬ pointed out that the main problems which should be considered in the urban ecology manipulative experimentꎬ and proposed the main development direction in the future: (1) Manipulative experiments on the compound impact of multiple environmental factorsꎻ (2) Manipulative experiments on the response of the ecosystem structure and functionꎻ (3) Long-term near-natural manipulative experimentsꎻ (4) Large-scale network of manipulative experimentsꎻ (5) Manipulative experiments on the urban ecological restoration and construction. We hope that

Peroxyacetyl nitrate (PAN) is a typical secondary photochemical product in the atmospheric environment with significant adverse effects on human health and plant growth. In this study, PAN and other pollutants, as well as meteorological conditions were observed intensively from August to September in 2022 at a typical urban sampling site in Beijing, China. The mean and maximum PAN concentrations during the observation period were 1.00 +/- 0.97 ppb and 4.84 ppb, respectively. Severe photochemical pollution occurred during the observation period, with the mean PAN concentration about 3.1 times higher than that during the clean period. There was a good positive correlation between O3 and PAN, and their correlation was higher during the O3 exposure period than that during the clean period. The simulated results by box-model coupled with the Master Chemical Mechanism (MCM v3.3.1) showed that the O3 -related reactions were the largest sources of OH radicals during O3 exposure period, which was conducive to the co -contamination of PAN and O3. Acetaldehyde (CH3CHO) and methylglyoxal (MGLY) were the largest OVOCs precursors of peroxyacetyl radicals (PA), with the contributions to the total PA generated by OVOCs about 67 % - 83 % and 17 % - 30 %, respectively. The reduction of emissions from liquefied petroleum gas (LPG) and solvent usage has the highest reduction effect on PAN and O3, followed by the control of gasoline vehicle exhaust emissions. This study deepens the understanding of the PAN photochemistry in urban areas with high O3 background conditions and the impact of anthropogenic activities on the photochemical pollution. Meanwhile, the findings of this study highlight the necessity of strengthening anthropogenic emissions control to effectively reduce the co -contamination of PAN and O3 in Beijing in the future.

城市植物是城市生物多样性的重要组成部分.城市植物多样性的长期定点监测与研究对保护城市生物多样性具有重要的意义.本文基于2007、2014和2020年对北京城区中的植物物种的三次实地调查结果,整理出北京城区植物物种名录数据集.本数据集包括维管植物物种130科535属1059种.通过对北京城区植物物种的全面摸底调查和长期监测,为城市植物多样性时空格局、植物对城市变化环境的响应等方面的研究提供数据支持.

Despite the importance of landscape design and water-resources management for urban planning, urban-forest transpiration was seldom estimated in situ. Detailed data on different urban trees’ water resource use and the effect of climatic fluctuations on their transpiration behaviour in different timescales are limited. In this study, we used a thermal dissipation method to measure the sap flux density (Js) of three urban tree species (Pinus tabulaeformis Carrière, Cedrus deodara (Roxb.) G. Don, and Robinia pseudoacacia Linn.) from 1 May 2008 to 30 April 2016 in Beijing Teaching Botanical Garden. The effects of environmental factors on sap flux density (Js) in different timescales were also analyzed. The results showed that there were significant differences in the sap flux density of three trees species in daily, seasonal, and interannual timescales. The hourly, seasonal, and interannual mean sap flux density of Pinus tabulaeformis were higher than that of Cedrus deodara and Robinia pseudoacacia. The seasonal mean Js of Pinus tabulaeformis, Cedrus deodara, and Robinia pseudoacacia in summer were 18.67, 16.19, and 41.62 times that in winter over 2008–2015. The annual mean sap flux density of Pinus tabulaeformis was 1.25–1.72 and 1.26–1.82 times that Cedrus deodara and Robinia pseudoacacia over 2008–2015. The Js responses in three tree species to environmental factors varied differently from daily to interannual timescales. The pattern of day-to-day variation in Js of three urban tree species corresponded closely to air temperature (Ta), soil temperature (Ts), solar radiation (Rs), and vapor pressure deficit (VPD). The Jarvis–Stewart model based on Ta, Rs, and VPD was more suitable for the sap flux density simulation of Pinus tabulaeformis than Cedrus deodara and Robinia pseudoacacia. The main factor affecting the sap flux density of Pinus tabulaeformis and Cedrus deodara was Ta in seasonal timescales. However, the main factor affecting the sap flux density of Robinia pseudoacacia was Ts. The interannual variations in the Js of Pinus tabulaeformis and Robinia pseudoacacia were mainly influenced by wind speed (w) and soil water content (SWC), respectively. The selected environmental factors could not explain the variation in the sap flux density of Cedrus deodara in an interannual timescale. The findings of the present study could provide theoretical support for predicting the water consumption of plant transpiration under the background of climate change in the future.