Analysis of a Tropical Warm Spring Microbiota Using 16S rRNA Metabarcoding

The Ikogosi Warm Spring is a unique ecological niche in Western Nigeria with an average temperature and pH of 38°C and 5.8 respectively. It mixes with an adjacent cold spring (28°C & pH 7.6), about 100 meters from source, yielding a confluence body of water of 32°C and pH 7.7. To explore the bacterial community structure of this uncommon environment and to scan for potentially useful bacteria, metagenomes extracted directly from five samples (source and mid-point of warm spring;source and midpoint of cold spring, and the confluence) were analyzed. Using the MiSeq Illumina next generation sequencing protocols, the V3-V4 region of the 16S rRNA gene pool was sequenced and analyzed by QIIME (Quantitative Insights into Microbial Ecology) and R software. At least 11% (47,446) of all the sequences were unknown to any of the databases employed. Bacterial diversity and abundance at the source of both springs were extremely low, accounting for less than 0.07% of the total sequence reads at the confluence, 100 m downstream. In contrast to the highly diversified mesophilic confluence community where 21 different phyla were identified, only 4 and 5 phyla were recovered from the source-point of the warm spring and cold spring respectively. The most prevalent phyla in all samples were members of the versatile Proteobacteria (35% - 50% relative abundance), and the hardy Firmicutes (33% - 40%). Operational taxonomic units (OTUs) obtained from all the samples averaged at 1414. Temperature and pH were equally significant predictors of genomic diversity and richness, with the warm and cold spring sources having less than 5 bacteria phyla. Exiguobacterium sp. (a potential plastic degrader) and other deep rooted bacteria were found in the warm spring while the cold spring outflow contained among others such as Rubrobacter sp. and Chloroflexi sp. (which is close to the phylogenetic root of the domain Bacteria). Many taxonomically unresolved sequences could indicate the presence of potentially novel bacteria in this unique body of water and underscores the need to systematically mine these rare genetic reservoirs for biotechnological applications. Moreover, such tropical hydrothermal ecosystems could contain some unknown primitive bacteria at the origins of life.

Contribution of Global Warming and Atmospheric Circulation to the Hottest Spring in Eastern China in 2018

The spring of 2018 was the hottest on record since 1951 over eastern China based on station observations,being 2.5°C higher than the 1961−90 mean and with more than 900 stations reaching the record spring mean temperature.This event exerted serious impacts in the region on agriculture,plant phenology,electricity transmission systems,and human health.In this paper,the contributions of human-induced climate change and anomalous anticyclonic circulation to this event are investigated using the newly homogenized observations and updated Met Office Hadley Centre system for attribution of extreme events,as well as CanESM2(Second Generation Canadian Earth System Model)simulations.Results indicate that both anthropogenic influences and anomalous anticyclonic circulation played significant roles in increasing the probability of the 2018 hottest spring.Quantitative estimates of the probability ratio show that anthropogenic forcing may have increased the chance of this event by ten-fold,while the anomalous circulation increased it by approximately two-fold.The persistent anomalous anticyclonic circulation located on the north side of China blocked the air with lower temperature from high latitudes into eastern China.Without anthropogenic forcing or without the anomalous circulation in northern China,the occurrence probability of the extreme warm spring is significantly reduced.

Changes in Mixed Layer Depth and Spring Bloom in the Kuroshio Extension under Global Warming

The mixed layer is deep in January-April in the Kuroshio Extension region. This paper investigates the response in this region of mixed layer depth （MLD） and the spring bloom initiation to global warming using the output of 15 models from CMIP5. The models indicate that in the late 21st century the mixed layer will shoal and the MLD reduction will be most pronounced in spring at about 33~N on the southern edge of the present deep-MLD region. The advection of temperature change in the upper 100 m by the mean eastward flow explains the spatial pattern of MLD shoaling in the models. Associated with the shoaling mixed layer, the onset of spring bloom inception is projected to advance due to the strengthened stratification in the warming climate.

暖冬及倒春寒天气对平欧杂种榛的影响及对策

平欧大榛子在我国栽培历史较短,由于品种多,栽培地域广泛,各地气候、土壤条件差异较大,加上种植者对各品种特性了解不足,生产上出现了各种各样的问题。该文就暖冬及倒春寒天气对平欧大榛子影响情况进行调查,并分析原因、提出应对的解决措施,希望能为种植户及拟发展该产业者提供帮助。

气候变化背景下青海省春小麦水分盈亏率时空分布特征

本研究旨在科学评价青海省春小麦种植区农业气候变化情况,并合理利用降水资源。采用线性倾向估计、突变检验、空间插值等方法,分析了1991—2021年青海省春小麦生育期气候要素变化趋势及水分盈亏率时空变化特征,并用通径法分析各气象要素与春小麦水分盈亏率的关系。结果表明:青海省春小麦生长期间,气温、≥0℃积温、降水量分别以0.3℃/10 a、50.7℃/10 a、23.6 mm/10 a的速率极显著上升,日照时数以66.6 h/10 a的速率极显著下降,各生育阶段变化趋势显著性不同;全生育期、茎叶生长期、孕穗开花期、灌浆成熟期水分盈亏率每年分别以0.864、1.020、0.464、1.771的百分率增加,孕穗开花阶段增加不显著,全生育期水分盈亏率于2011年发生突变;从地区分布结果来看,水分盈亏率由东向西逐渐减小,河湟谷地水分亏缺较少,青海湖盆地次之,柴达木盆地水分亏缺严重;降水量对水分盈亏率产生显著的正效应,日照、风速、最低气温对水分盈亏率产生显著负效应。研究表明,青海省春小麦种植区气候呈现暖湿化趋势,并且春小麦水分亏缺问题严重,但亏缺程度有所减缓。该研究有助于掌握青海春小麦种植区的气候变化规律,并提高应对干旱灾害风险的能力。

Spring mesoscale high in the western South China Sea

A recurring spring mesoscale eddy in the western South China Sea （SCS） is studied using remote sensing data and historical in situ observations. The feature first appears east of the central Vietnam coast in Febru- ary as a high sea-level anomaly, grows rapidly to a well-developed anticyclonic eddy by March, matures in April, and decays in May. Besides the warm-core feature, it also has an inherent low-salinity property, so it is named ＂spring mesoscale high （SMH）＂. Though with clear interannual variation in terms of intensity and spatial coverage, the SMH always emerges in the region between ll0~E and l14~E and between 12~N and 16~N. The formation of SMH is ascribed to the combined effects of wind forcing and releasing of po- tential energy set up by winter monsoon. In particular, the wind-stress curl plays an important role in its development, maintenance, and dissipation.

创作与表演双重视角下的当代筝乐演绎——以《暖春》的演奏实践为例

《暖春》是作曲家赵曦应湖北省音乐家协会古筝专业委员会委约,从2020年2月至2021年2月,历时一年创作的古筝与管弦乐队作品,作曲家以此讴歌为武汉送来“暖春”的人们。文章以作品创作构思、乐谱完善、演绎过程为依据,着重探讨了创作与表演双重视角下的交互融合对作品演绎所产生的积极意义。

INTERANNUAL VARIATION IN HEAT CONTENT OF THE WESTERN PACIFIC WARM POOL AND ITS EFFECT ON EASTERN ASIAN CLIMATE ANOMALIES

Using the 1980-2010 winter GODAS oceanic assimilations, study is conducted of the winter heat content(HC) established in the subsurface layer(5 to 366 m in depth) over the western Pacific warm pool(WP), followed by investigating the HC spatiotemporal characteristics, persistence and the impacts on the climate anomalies of neighboring regions. Results are as follows: 1) the pattern of integral consistency is uncovered by the leading EOF1(PC1) mode of HC interannual variability, the year-to-year fluctuation of the time coefficients being well indicative of the interannual anomaly of the WP winter subsurface-layer thermal regime. The HC variation is bound up with El Ni觡o-Southern Oscillation, keeping pronounced autocorrelation during the following two seasons and more, with the persistence being more stable in comparison to sea surface temperature anomaly in the equatorial middle eastern Pacific; 2) the winter HC anomalies produce lasting effect on the WP thermal state in the following spring and summer and corresponding changes in the warm water volume lead to the meridional transport and vertical exchange of warm water, which exerts greater impacts upon the sea surface temperature/heat flux over the warm pool per se and neighboring regions, especially in the Philippine Sea during the posterior spring and summer; 3) the increase in the winter HC corresponds to the spring outgoing longwave radiation(OLR) decrease and richer precipitation over the waters east to the Philippine Sea and the resultant convective heating anomalies are responsible for the rise of geopotential isobaric surfaces over tropical and subtropical western North Pacific, thereby producing effect on the western Pacific subtropical high(anomaly). Subsequently, the sea-surface heat flux exchange is intensified in the warm pool, a robust anomalous cyclone shows up at lower levels, air-sea interactions are enhanced and abnormal convective heating occurs, together making the winter HC anomalies even more closely associated with the variation in the summer subtropical high. As a result, the WP winter HC can be used as an effective predictor of the variation in spring/summer western Pacific subtropical high and the strength of summer monsoon over the northwestern Pacific.

Warm compaction behaviors of iron-based powder lubricated by different kinds of graphite

Warm compaction behaviors and their affecting factors such as compaction temperature, compaction pressure and lubricant concentration were studied. Effect of die wall lubrication on the powder’s warm compaction behavior was also studied. The use of smaller size colloidal graphite investigated can give a higher compact density and lesser spring back effect than the use of flake graphite.

热解温度和氮肥用量影响生物炭的减排和增产效应

【目的】研究生物炭性质与氮肥用量对河套灌区春玉米田温室气体排放和产量的影响,为河套灌区高效利用生物炭固碳减排提供理论支撑。【方法】试验采用室内培养与田间试验相结合的方法,供试材料为秸秆生物炭和竹炭。田间试验设常规施氮300 kg/hm^(2)对照(N)、常规氮量配施秸秆炭(SB+N)、常规氮量配施竹炭(BB+N)、减氮50%配施秸秆炭(SB+50%N)、减氮50%配施竹炭(BB+50%N)。采用静态暗箱–气象色谱法测定春玉米田温室气体排放量,并测定玉米产量。室内培养试验中分别制备热解温度为200℃、400℃和600℃的秸秆炭(S)和竹炭(B)加入土壤中,平衡3天后施入N 300 kg/hm^(2)开始恒温恒湿培养,共培养14天。监测了不同培养时间土壤中N_(2)O、CO_(2)及CH_(4)气体的排放通量。【结果】与N处理相比,SB+N、BB+N、SB+50%N和BB+50%N处理0—5 cm深土壤温度分别提高了0.50℃、1.84℃、0.35℃和1.37℃,0—10 cm深土壤温度分别提高了0.43℃、1.83℃、0.39℃和1.11℃;0—10 cm土壤含水率分别提高13.70%、8.90%、12.33%和8.90%。与N处理相比,在春玉米整个生育期内SB+N、BB+N、SB+50%N和BB+50%N处理的土壤N_(2)O累积排放量分别减少了21.91%、23.16%、25.98%和28.17%(P<0.05);SB+N和BB+N处理的CO_(2)累积排放量分别提高了7.96%和9.94%(P<0.05),而SB+50%N和BB+50%N处理的分别降低了11.54%和10.74%(P<0.05);整个春玉米生育期各生物炭处理的CH_(4)累积排放量为负值,显著低于N处理(P<0.05);SB+N、BB+N、SB+50%N和BB+50%N处理土壤的全球增温潜势(GWP)分别降低了23.26%、23.98%、27.00%和29.14%,温室气体排放强度(GHGI)分别降低了27.24%、28.97%、32.57%和34.68%(P<0.05)。生物炭添加能够提高玉米产量,SB+N、BB+N、SB+50%N和BB+50%处理较N处理分别增加5.47%、7.01%、8.26%和8.47%(P<0.05)。培养试验发现生物炭能够减少土壤N_(2)O和CO_(2)的排放。N_(2)O和CO_(2)的排放通量随生物炭热解温度升高而减少,在相同热解温度下,竹炭的减排效果优于秸秆炭。各处理下土壤CH_(4)的排放均表现为碳汇,其中600℃制备的竹炭对CH_(4)的吸收量最高。【结论】施用生物炭能够改善土壤温度和土壤含水率,并显著降低N_(2)O和CH_(4)累积排放量,但常规施氮量下施用生物炭会提高CO_(2)累积排放量。施用生物炭能够显著提高春玉米的产量并降低春玉米田GWP和GHGI。培养试验进一步说明了竹炭的减排效果优于秸秆炭,高热解温度的生物炭减排效果优于低热解温度生物炭,综合考虑田间与室内培养试验的结果、环境效益和经济效益,减氮50%配施竹炭的处理是河套灌区春玉米田提高产量并减少温室气体排放较为合适的措施。

北京东灵山森林木本植物物候对气温响应的季节差异

[目的]明确北京东灵山暖温带森林木本植物不同物候期对气候变暖响应的季节性差异。[方法]本文利用2003-2019年北京市暖温带森林24种木本植物的6种物候期数据,采用偏最小二乘回归和相关分析计算各物候期对季节气温响应的最优相关时段,并应用Wilcoxon符号秩检验对比各物候期对相关时段内气温响应敏感度的差异。[结果]展叶始期、始花期和盛花期对气温响应的最优相关时段分别为物候期前48、64、55 d(3月上中旬至4月底、5月上中旬),该时段内气温每升高1℃,始花期平均提前6.38 d,显著高于展叶始期(提前4.52 d)和盛花期(提前5.05 d)。萌芽期对气温的响应方式与上述3种物候期不同,其最优相关时段为秋冬季10月28日至下一年1月14日,其次是冬春季3月11日至4月14日(萌芽期前34 d)和夏季7月14日至8月27日。秋冬季相关时段气温每上升1℃,萌芽期提前5.48 d,显著高于冬春气温使其提前的天数(3.71 d),而夏季气温上升1℃使萌芽期推迟9.74 d,与其他均显著不同。与普遍的观点不同,叶变色期和落叶期对气温响应的最优相关时段为春夏季4月初至7月中下旬,而对夏秋季(8月下旬至9月中下旬)气温响应显著的物种很少。在气温上升1℃的情况下,春夏季相关时段气温使叶变色期和落叶期分别提前7.12和9.55 d,而夏秋季气温使其分别推迟2.27、5.96 d。近50年,研究点冬末春初(2、3月)气温的上升速度是其他月份的2倍以上,而秋冬季(10—12月)气温无显著变化。[结论]北京东灵山森林木本植物各物候期对不同季节气温的响应方式和强度具有显著差异,且各季节气温的变化呈现不一致性,这可能会对从植物个体到生态系统的各个层次都产生深刻的影响。

电视剧《三泉溪暖》的生态美学研究

中央广播电视总台CCTV一套热播的电视剧《三泉溪暖》延续了鲁剧一以贯之的温暖现实主义风格,展现出浓郁的时代气息与齐鲁风情,且立意鲜明深刻,极富生态文明观念,呈现了一幅人与自然和谐共生的乡村式发展图景。文章从生态美学的维度对电视剧《三泉溪暖》进行分析,不仅深入挖掘和解读作品中的思想价值与现实意义,更为创新和转型现代乡村治理提供了有益思考,为当下可持续发展语境下乡村振兴的潜在问题与现实困境探索了可供参考的解决之道。

山东半岛温泉的地热属性及其特征

从山东半岛所处的板块构造位置和局部的控热构造入手 ,根据地热传导的理论 ,对山东半岛温泉的地热属性进行研究分析 ,认为山东半岛温泉地热属性为濒临板缘高温地热带的板内中低温地热系统 ,它以偏高的大地热流值为地热背景 ,以局部控热构造聚敛的大地热流为热源 ,以地形高差影响和相应的水力压差作用为动力 ,入渗的大气降水吸收岩石中的热量而被加热 ,并沿断裂出露形成温泉地热水。

近20年东北气候变暖对春玉米生长发育及产量的影响

【目的】探求东北三省近20年气候变暖对春玉米生长发育进程及产量的影响,为东北地区气候变暖下粮食安全问题提供理论依据。【方法】选取东北黑龙江、吉林和辽宁省三省进行区域研究,利用东北地区近20年气候观察数据和春玉米长期观测数据,通过相关和回归等数理统计方法系统分析东北三省春玉米生长季的气候因子(温度和降水量)与春玉米生育进程数据和历史产量数据之间的关系。【结果】东北地区1989—2009年春玉米生长季日最高温度、最低温度以及平均温度均呈明显上升趋势,气候倾向率每年分别为0.050、0.045和0.044℃,表现为春玉米生育期间白天增温幅度较夜间增温幅度大,降水量变化不显著。近20年黑龙江省各试验站平均播种日期变化趋势是每年提前0.10 d,而吉林省、辽宁省各试验站每年分别推迟0.18和0.21 d。黑龙江省、吉林省以及辽宁省各试验站春玉米平均成熟日期变化趋势分别每年推迟0.39、0.35和0.55 d,平均生育期天数变化趋势分别每年增加0.49、0.17和0.34 d,成熟日期推迟的幅度大于播种日期的推迟幅度导致三省试验站春玉米生育天数增加。对1991—2006年东北地区审定品种生育期数据与气候数据关系进行相关性分析表明,黑龙江省最高温度(Tmax)上升会延长审定品种生育期,而吉林和辽宁省春玉米的审定品种生育期与平均温度(Tavg)、最高温度(Tmax)和最低温度(Tmin)均呈现为正相关。采用T检验法分析春玉米审定品种生育期和试验站春玉米生育期关系表明,黑龙江和辽宁省的审定品种和试验站春玉米生育天数呈一致的增加趋势,且无显著性差异。采用线性偏回归测验法分析品种和气候因子对春玉米生育期影响重要性的结果表明,品种生育期的延长是导致春玉米生育期不断延长的主要原因。三省春玉米近20年平均产量表现为增加趋势,其趋势由小到大的次序是辽宁省、吉林省以及黑龙江省,越往北其产量增加趋势越大,产量增加越明显。东北各省地级市1989-2009年面板数据分析表明,东北地区平均温度(Tavg)、最高温度(Tmax)和最低温度(Tmin)的变化均会影响春玉米的产量。温度上升,东北部产量增加明显,尤其是黑龙江省东部的三江平原地区,而东北地区西南部减产。【结论】受气候变暖的影响,东北春玉米品种对气候变暖是逐步适应,可以利用其适应潜力,通过春玉米品种改良和调整播期等措施来适应气候变暖,从而提高春玉米产量。

模拟增温对半干旱雨养区春小麦物质生产与分配的影响

为了明确未来气候变化对半干旱区春小麦生产的影响,了解增温条件下春小麦不同生长阶段物质生产的响应特点以及光合产物在不同器官中的分配特征,利用开放式红外增温系统设置不同的温度梯度,即不增温(对照)、增温1和2℃,模拟田间增温对春小麦物质生产与分配的影响。结果表明:温度增加,春小麦发育加快,全生育期明显缩短,增温1和2℃,比对照分别缩短7和11 d;从各器官干物质生产来看,相对于对照,在增温1、2℃处理下,叶干物质质量在三叶期分别增加了11.23%和27.49%,在拔节期及其以后分别平均降低了20.12%和30.83%。茎干物质质量在拔节期及其以前分别平均增加了17.30%和30.30%,拔节期以后分别平均降低了13.19%和22.09%。根干物质质量在孕穗期及其以前分别平均增加了10.26%和23.30%,孕穗期以后分别平均降低了15.79%和26.05%。穗干物质质量分别平均降低16.43%和29.00%;增温处理下春小麦物质生产随时间的响应规律主要是由净同化率的变化所致;从各器官干物质分配来看,与对照相比,增温1、2℃处理下,春小麦叶和穗干物质质量占全株干物质质量的比例在整个生育期分别平均下降了8.32%、12.01%和0.56%、3.40%,且增温幅度越大,下降的越多。增温1、2℃处理下,茎和根干物质质量占全株干物质质量的比例在整个生育期分别平均增加了3.92%、6.25%和3.86%、8.71%,且增温幅度越大,增加的越多。结果为中国半干旱区春小麦对全球气候变化下的敏感性及适应性研究提供理论参考。

青岛即墨温泉喷流沉积物及其沉积模式

本文应用XRD测试技术和岩石地层学方法、生物地层学方法,将即墨温泉地热区第四系划分为层Ⅰ、层Ⅱ1、层Ⅱ2和层Ⅲ,根据沉积物中所含石膏、岩盐等与温泉地热水相关的自生矿物的空间分布和以直隶小旋螺(Gyraulus chihliensis)为代表的腹足类陆生软体动物化石,以及以土星介(Illyocypris sp.)为代表的节肢动物介形虫化石的空间分布,确立Ⅱ1层为温泉喷流沉积,是第四纪活动断裂控制的地球化学异常的产物,以此建立起温泉喷流沉积模式。

气候变暖将显著降低引黄灌区春小麦产量和氮磷钾养分吸收

【目的】探索宁夏引黄灌区春小麦不同生育时期氮(N)、磷(P)、钾(K)养分吸收利用对气候变暖的响应机制,为预测气候变暖对干旱半干旱区春小麦生长的影响提供依据。【方法】试验于2018年3月在宁夏银北引黄灌区宁夏大学试验站进行。供试春小麦品种为‘宁春50号’,供试肥料为磷酸二铵和尿素。采用自动控制红外线辐射器进行野外增温,每个小区内分别设置一组红外灯管作为增温装置、一套自动控温电子设备与一组可移动温度传感器作为控温装置,增温装置直接连接控温装置以使增温梯度达到预设水平,增温时间为昼夜不间断增温。以春小麦冠层自然温度为对照温度(增温0℃,CK),设置4个增温梯度(0.5℃、1℃、1.5℃、2.0℃)处理。于苗期、拔节、抽穗、灌浆、灌浆后10天、成熟期采集植株样品,测定叶、茎、穗的N、P、K养分含量,计算地上部各器官的养分累积吸收量、养分分配率和地上部植株养分累积量,并测定春小麦植株地上部干物重和产量。【结果】增温0.5℃,春小麦植株苗期干物重、拔节期地上部各器官N、P、K养分含量及养分累积吸收量均显著高于CK。增温1.0℃,苗期植株N、K含量和N素吸收量以及拔节期叶片的N、P、K含量显著高于CK,较对照提高3.2%~23.7%。增温1.5℃,仅苗期植株K含量显著高于CK,较对照提高22.2%。增温2.0℃,从苗期开始各项指标均显著低于CK。拔节期以后,除增温0.5℃春小麦K素含量与CK差异不显著外,其余指标均显著低于CK,春小麦成熟期小穗数、穗粒数、千粒重、产量均随温度的升高呈下降的趋势,增温2.0℃,分别较对照降低53.7%、24.1%、13.4%、21.7%。增温梯度越大,各指标下降的幅度越大。【结论】春小麦苗期温度升高0.5℃~1.0℃尚有利于拔节期前春小麦对N、P、K养分的吸收,但拔节期后增温超过1.0℃以上都会对N、P、K养分吸收产生显著负作用,导致使生育后期干物质的累积量减少,千粒重、穗粒数等降低,并最终导致产量和品质的下降。

胶东半岛温泉的地热特征

胶东半岛位于欧亚板块与太平洋板块边缘内侧 ,是地壳长期稳定缓慢隆起地段 ,区内地质构造发育 ,大部分温泉出露在背斜核部 ,NE、NNE向与 NW、NNW向断裂交汇处。地热系统属中低温深循环对流型 ,略为偏高的大地热流是其主要热源 ,地表水是地下热水的补给水源 ,地下水通过发育在花岗岩和变质岩中的断层或断裂破碎带 ,下渗和深循环对流 ,在径流过程中不断吸取围岩热量成为热水 ,沿断裂上升过程中 ,与地下浅部裂隙水混合而成为化学成分各异 ,温度高低不等的温泉水。

青海高原不同海拔高度区小麦生长对气候变暖的响应

利用青海高原上两个不同海拔高度区农业气象观测站1980—2007年的观测资料,就低海拔地(民和)和高海拔地(诺木洪)的气候变化及其对春小麦生长发育和产量的影响差异进行研究。结果显示:28年来民和和诺木洪两站均存在变暖趋势,且高海拔地区的线性增暖幅度大于低海拔地区。春小麦对气候变暖的响应表现在低海拔地区播种期提前,成熟期基本没有变化,生育期延长,产量下降;高海拔地区播种期推迟,成熟期提前,生育期缩短,产量波动较大。春小麦生长期内日平均气温每升高1℃,高海拔地区春小麦生育期缩短11.7 d,而低海拔地区无显著变化。分蘖期是两地小麦生育时期变化的转折点,是环境与群体的"缓冲者"。

山东半岛温泉的分布规律与成因

根据对山东半岛地热场特征、区域地质构造、岩浆活动与温泉分布关系的研究以及地热水化学特征的分析，认为温泉的形成与分布主要受断裂构造的控制。温泉的形成机理为深循环－地热增温，即大气降水或第四系潜水沿断裂带深循环，在正常地温梯度下吸收地球内热增温形成热水，再沿断裂破碎带上涌至地表而形成温泉。温泉水温取决于地下水循环深度，按笔者提出的经验公式推算，山东半岛１４处温泉水的最小循环深度界于１５０３～３０８４ｍ间。