Southern Foot Research Articles

Integrating magnetic and stratigraphic data to delineate the subsurface features in and around new Galala City, Northern Galala Plateau, Egypt

ABSTRACTThe Egyptian Government is developing a new city, Galala, above the Northern Galala Plateau, western side of Gulf of Suez between Ain Sukhna and Zafarana. The aim of the study is integrating magnetic and stratigraphic data to delineate the subsurface features beneath the New Galala City, in order to avoid the possible geological hazards. The stratigraphic succession in the study area consists of Precambrian basement complex overlain unconformably by Phanerozoic sequence. The Phanerozoic sequence composed mainly of siliciclastic-dominated rocks superimposed by carbonate-dominated rocks. The carbonate-dominated rocks cover most surface area, whilst the siliciclastic-dominated rocks exposed along eastern and southern foot slope of the Northern Galala Plateau. The observed palaeo-karst surfaces, fissures, caves, sink-holes and fault zones within carbonate rocks may cause some geological hazards in the study area. The total intensity aeromagnetic map was subjected to un-prescribed structural index 3D-Euler Deconvolution (ED), the tilt angle derivative (TDR) and the power spectrum in order to estimate both trends and source depths. The source depths range from 500 m to 4000 m, which result from the Precambrian basement complex. However, the trends of encountered structural elements are mainly NE–SW, NW–SE, NNW–SSE and E–W directions.

The Development of Ecotourism Model at Natural Attractions of Tete Batu Village in East Lombok

Tourist village of Tete Batu is located at Sikur District in East Lombok Regency, Nusa Tenggara Barat Province. With its scenic beauty along the southern foot of Rinjani Mountain and its green, natural, beautiful and mild countryside atmosphere, Tete Batu Village offers economic potential to its community. Tourism sector needs a good tourism development that can develop existing potential with a maximum result. This research was aimed to find the effect of natural attraction development in Tete Batu Village that adopted Ecotourism Model in the interest of increasing the number of tourist arrivals. Technique of data analysis being used was SWOT analysis with qualitative approach. There were two types of data that were collected, namely primary and secondary data. Primary data was obtained through field observation, interview and questionnaire, while secondary data was collected from related literature study. The result showed that natural attractions in Tete Batu village could be developed by using Ecotourism model because its condition could attract tourists and the management was done by the society and based on local nature and culture.

Characteristics of soil organic carbon and total nitrogen under various grassland types along a transect in a mountain-basin system in Xinjiang, China

Soil organic carbon (SOC) and soil total nitrogen (STN) in arid regions are important components of global C and the N cycles, and their response to climate change will have important implications for both ecosystem processes and global climate feedbacks. Grassland ecosystems of Funyun County in the southern foot of the Altay Mountains are characterized by complex topography, suggesting large variability in the spatial distribution of SOC and STN. However, there has been little investigation of SOC and STN on grasslands in arid regions with a mountain-basin structure. Therefore, we investigated the characteristics of SOC and STN in different grassland types in a mountain-basin system at the southern foot of the Altai Mountains, north of the Junggar Basin in China, and explored their potential influencing factors and relationships with meteorological factors and soil properties. We found that the concentrations and storages of SOC and STN varied significantly with grassland type, and showed a decreasing trend along a decreasing elevation gradient in alpine meadow, mountain meadow, temperate typical steppe, temperate steppe desert, and temperate steppe desert. In addition, the SOC and STN concentrations decreased with depth, except in the temperate desert steppe. According to Pearson's correlation values and redundancy analysis, the mean annual precipitation, soil moisture content and soil available N concentration were significantly positively correlated with the SOC and STN concentrations. In contrast, the mean annual temperature, pH, and soil bulk density were significantly and negatively correlated with the SOC and STN concentrations. The mean annual precipitation and mean annual temperature were the primary factors related to the SOC and STN concentrations. The distributions of the SOC and STN concentrations were highly regulated by the elevation-induced differences in meteorological factors. Mean annual precipitation and mean annual temperature together explained 97.85% and 98.38% of the overall variations in the SOC and STN concentrations, respectively, at soil depth of 0–40 cm, with precipitation making the greatest contribution. Our results provide a basis for estimating and predicting SOC and STN concentrations in grasslands in arid regions with a mountain-basin structure.

PRESENCE STATE OF TRACE ELEMENTS IN THE OHTAKIGAWA RIVER WATERSHED FROM THE FOOT OF Mt. ONTAKE

This paper is aimed at understanding the influence of Mt. Ontake volcanic activity on the water quality of the Ohtakigawa River watershed. For this purpose, various properties of trace elements are obtained. The Ohtakigawa, which flows along the southern foot of Mt. Ontake, has several tributaries such as Nigorigawa River, Shirakawa River, Shimokurosawa River, and Uguigawa River. Seven sampling stations were selected in the four tributaries (four points) and the Ohtakigawa (three points). Filtration of samples wascarried out with teflon filter paper (PTFE, 0.5μm, φ 47mm), and the samples were separated into dissolved and suspended matters. Trace elements contained in them were analyzed by using the ICPE. The concentrations of the trace elements were high in the following order: the Nigorigawa (Al: 6.16mg L-1), the Ohtakigawa after the confluence of the Nigorigawa (Al: 1.92mg L-1 and 0.88mg L-1), and the others (Al: 0.06-0.70mg L-1). This result indicates that among the four tributaries, the Nigorigawa plays a predominantrole in the change in the water quality of the Ohtakigawa.

Simulation on photosynthetic-CO2 response of Quercus variabilis and Robinia pseudoacacia in the southern foot of the Taihang Mountain, China.

In this study, leaf photosynthetic CO2-response curves of Quercus variabilis and Robinia pseudoacacia were measured using a Li-6400XT photosynthetic measurement system in the southern foot of the Taihang Mountain, China. The rectangular hyperbola model (RH), nonrectangular hyperbola model (NRH) andYe model (YZP) were used to fit photosynthetic-CO2 response curves and compare photosynthetic parameters, including the maximum net photosynthetic rate (Amax), the initial carboxylation rate (η), light respiration rate (Rp), CO2 compensation point (CCP) and CO2 saturation point (CSP). Compared with the NRH and YZP models, Amax, η, Rp and CCP obtained by the RH model were higher, and were 59.8%, 128.6%, 133.4% and 19.8% higher than the measured values. The accuracy of the RH model was lower and its relative error was higher than that of the NRH and YZP models.Compared with the RH and YZP models, Amax fitted by the NRH model was higher, and was 11.1% higher than the measured value. η, Rp and CCP fitted by the NRH model were closer to the measured values. CO2 saturation phenomenon of photosynthesis could be simulated by the YZP model, and Amax and CSP were fitted well. Amax, Rp and CCP in the shaded leaves of Q. variabilis were 31.3%, 5.2% and 14.3% lower than those in the sunlit leaves. Amax, Rp and CCP in shaded leaves of R. pseudoacacia were 23.5%, 11.0% and 5.4% more than those in the sunlit leaves. η in the shaded leaves of Q. variabilis and R. pseudoacacia were 6.9% and 7.0% higher than those in the sunlit leaves, respectively. Rp and CCP of R. pseudoacacia leaves had linear relationships with temperature (T) and photosynthetic active radiation (PAR), and η had a significant relationship with stomatal conductance (gs). η of Q. variabilis leaves was linearly correlated with PAR and gs, and CCP was affected by T and relative humidity. Amax of Q. variabilis leaves had significant positive linear relationships with RH and gs.

The Transfiguration of Agriculture and Rural for 150 Years in the Southern Foot of Yatsugatake in Yamanashi Prefecture, and the Future

The Transfiguration of Agriculture and Rural for 150 Years in the Southern Foot of Yatsugatake in Yamanashi Prefecture, and the Future

Time and place changes concentration of nitrite nitrogen in the southwestern part of the Slovak Republic

Received: 2016-10-24 | Accepted: 2017-04-19 | Available online: 2017-06-20 http://dx.doi.org/10.15414/afz.2017.20.01.41-44 Concentrations of nitrite nitrogen in the water flow Caradice brook were evaluated in the years 2005-2010. Caradice brook springs in the mountains of Pohronský Inovec in the southern foot of Drienka hill and it is the right tributary of the Hron River, into which mouth near the village Kozarovce. Its length is 11.1 km. Samples of the water in longitudinal profile of the watercourse were carried out from six sampling sites, on a regular basis, in the second decade of the month. The places of taking samples were localized to include all real sources causing the pollution of watercourse. The average concentration of nitrite nitrogen during the whole period represented a value of 0.05 mg dm -3 . Its share in total inorganic forms of nitrogen (N-NO 3 - , N-NH 4 + , N-NO 2 - ) represented 1.98%. Depending on the time of sampling the lowest average concentration for the whole period was recorded in February (0.032 mg dm -3 ). Its highest average concentration was detected in May (0.065 mg dm -3 ). Seasonal dynamics regularity of concentrations of nitrite nitrogen during the whole monitored period is not reflected. Effect of sampling sites on the nitrite nitrogen concentration in the water flow was as significant as the influence of the month. In the longitudinal profile of the watercourse, we generally observed a tendency of gradual increase in the concentration from the first to the last sampling site. The lowest average concentration of nitrite nitrogen (0.025 mg dm -3 ) was found in the sampling site, which was located under the forest ecosystem and the highest (0.066 mg dm -3 ) in the sampling point located below the village Kozarovce. The most significant increase in the average concentration was found in the sampling site located under Caradice municipalities and Kozarovce, which may indicate contamination of sewage water flow. In the regulation of the Government of the Slovak Republic No. 269/2010 Coll. the recommended value for nitrite nitrogen is 0.02 mg dm -3 . Calculated values of 90-th percentile (P90) of this indicator in all sampling sites were lower than the recommended value of government regulations. Keywords: nitrite nitrogen, water flow, water quality References ABER, J.D. et al. (2002) Is Nitrogen Deposition Altering the Nitrogen Status of Northeastern Forests. American Geophysical Union . Vol. 31, 6 pp. BABOSOVA, M. and NOSKOVIC, J. (2014) The quality of atmospheric precipitation in the area of Nitra - Lower Malanta . Nitra: Slovak University of Agriculture in Nitra. 64 p. Barancikova, G. et al. (2009) Environmental Chemistry . Presov: Presov University. 251 p. BUDAY, J. (2002) Intensification of the process of removing nitrogen from sewage - substrate and product inhibition of nitrification. Bratislava, pp. 92. KABELKOVA-JANCARKOVA, I. (2002) Nitrification dynamics in a small watercourse. Water management , vol. 52, no. 8, pp. 221 – 224. Konecný, V. (1998) Geological map of the Stiavnicke hills and Pohronsky Inovec . VEDA: Bratislava. LICHVAROVA, M. et al. (2006) Properties of water. Project KEGA 3/3004/05. GOVERNMENT DECREE of the Slovak Republic No. 269/2010 Coll. NOSKOVIC, J. et al. (2010) Zitavsky luh – abiotic components . Nitra: Slovak University of Agriculture in Nitra. 157 p. NOSKOVIC, J. et al. (2011) Nature Reserve Aluvium Žitava water quality . Nitra: Slovak University of Agriculture in Nitra. 105 p. PITTER, P. (1999) Hydrochemie. Prague, pp. 568. PITTER, P. (2009) Hydrochemie. 4 th ed. Prague, pp. 568. SEBIŇ, M., PEKAROVA, P. and MIKLANEK, P. (2007) Evaluation and indirect estimation of nitrate losses from the agricultural microbasin Rybarik. Biologia , vol. 62, no. 5, pp. 569-572. VALENT, P. et al. (2011) Analysis of nitrate concentrations using nonlinear time series models. Journal of Hydrology and Hydrochemics , vol. 59, no. 3, pp. 157 – 170. doi: http://dx.doi.org/10.2478/v10098-011-0013-9

A2-15 南麓での火山層序と全岩化学組成からみた開聞岳火山の形成史(新燃岳2011年噴火と南九州の火山,口頭発表)

A2-15 南麓での火山層序と全岩化学組成からみた開聞岳火山の形成史(新燃岳2011年噴火と南九州の火山,口頭発表)

Fractured gravels and fracture system in the southern foot of the Sekita Mountains, Niigata-Nagano prefectural border region, central Japan

Fractured gravels and fracture system in the southern foot of the Sekita Mountains, Niigata-Nagano prefectural border region, central Japan

模拟氮沉降对荆条灌木“肥岛”土壤养分的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 模拟氮沉降对荆条灌木“肥岛”土壤养分的影响 DOI: 10.5846/stxb201607211485 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（31270750） Effects of simulated nitrogen deposition on soil nutrients of Vitex negundo L. var. “fertile islands” Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:氮沉降的增加，可能会对土壤养分造成更为显著的影响，目前关于大气氮沉降对植物"肥岛"效应中土壤养分的影响鲜有报道。于河南省太行山南麓地区，以NH4NO3为供施氮源，按土层深度采集土样，以模拟氮沉降方法（3个水平，无氮CK、低氮2 gN m-2 a-1处理、中氮12gN m-2 a-1处理和高氮24gN m-2 a-1处理），分析了氮沉降对太行山荆条灌木（Vitex negundo L.var.）"肥岛"土壤中有机质、全氮和速效磷含量的影响。结果表明：灌木"肥岛"中全氮和速效磷含量，总体表现出随氮沉降量增长而增加的趋势；氮沉降显著增加了土壤表层有机质、氮、磷的含量；高氮沉降与CK相比引起的各土层间养分差异更显著；随着氮沉降水平的增加，冠幅内外和土层间养分差异增大，土壤养分的增长率随之加大；氮沉降在一定程度内加剧了"肥岛"的富集效应，且氮沉降量越大，这种富集效应越显著。这些研究结果可为研究灌木"肥岛"对外源氮的响应机制及保育作用提供参考。 Abstract:Nitrogen deposition may have a significant effect on soil nutrients; however, research regarding the influence of atmospheric nitrogen deposition on the soil nutrients of the plant "fertile islands" is limited. In this field study, we analyzed the Vitex negundo L. var. "fertile islands" distributed in the southern foot of the TaiHang Mountain Range, Henan Province. Simultaneously, ammonium nitrate (NH4NO3) was selected as the nitrogen source, and soil samples were collected from different soil depths. The research simulated nitrogen deposition (three levels, including a low-nitrogen treatment, 2 gN m-2 a-1; secondary-nitrogen treatment, 12 gN m-2 a-1; and high-nitrogen treatment, 24 gN m-2 a-1) to analyze the impacts on organic matter, total nitrogen, and available phosphorus contents embedded in the "fertile islands". The results demonstrated that the amount of total nitrogen and available phosphorus contents in "fertile islands" increased with the increase in nitrogen deposition. Organic matter, nitrogen, and phosphorus contents on the soil surface increased obviously with increased nitrogen deposition. Compared with that of the control, the differences in the nutrient contents of soil layers caused by high nitrogen deposition were more obvious. Nutrient differences between the crown and soil layers increased, and the soil nutrients increased with the increase in nitrogen deposition. Nitrogen deposition intensified the "fertile island" aggregation effect to a certain extent, which became more prominent as a result of the increased nitrogen deposition. The results provide a baseline to analyze the response mechanisms and conservation function of nitrogen fertilization in "fertile islands". 参考文献 相似文献 引证文献

The Maritime Approaches to Ancient Byblos (Lebanon)

ABSTRACTMaritime trade between Levantine coastal cities over the millennia is attested in numerous ancient sources. Information from these textual and iconographic works often describes the timber trade between Byblos and Egypt. However, no physical trace of a Bronze Age harbor has been discovered around ancient Byblos. After 17 years of field investigation, a harbor basin has finally been located at the southern foot of the ancient city. In 2011, the geo-archaeological research program Byblos and the Sea was launched to shed new light on the maritime approaches to Byblos. Several indications confirm the location of a silted-in harbor basin, most probably the harbor, which is so vividly described in the Report of Wenamun.

Connection between the appearance of γ-ray sources and Hα line impact linear polarization in the July 23, 2002 flare

During our spectropolarimetric observations of the 2B/4.8X flare on July 23, 2002, with the Large Solar Vacuum Telescope (LSVT), we detected impact linear polarization in the southern ribbon. The maximum polarization exceeded 10%. On the whole, the polarization was observed only for ~6 min out of almost 2 h of observations of this flare. At this time, the Hα line profiles had a deep central self-reversal. We have compared the LSVT observations with the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) data, where the locations of γ-ray emission were obtained for the first time. A careful comparison has revealed that the effects in the Hα line were observed in a region <10″ located between two X-ray sources in the southern ribbon. According to the RHESSI data, a γ-ray source attributable to a beam of high-energy (~1 MeV) electrons was observed at the same place. The events in the corona and the upper chromosphere also coincide in time with the observed effects in the Hα line. The two X-ray sources are assumed to represent a common footpoint of the southern foot of the loop bifurcated due to the precipitation of high-energy electrons. It is suggested that the penetration of these electrons into the dense layers of the chromosphere could lead to impact polarization and a decrease of the Hα line intensity in the southern ribbon of the flare, in contrast to the northern ribbon where a typical hard X-ray source with an energy ~20–120 keV was observed; there were no self-reversal at the Hα line center and polarization.

Characteristics and Mechanisms of the Subseasonal Eastward Extension of the South Asian High

Abstract This study investigates the features of eastward extension of the South Asian high (SAH) and its connection with diabatic heating and rainfall over eastern Asia on subseasonal time scales. The causes of SAH’s eastward extension are examined by potential vorticity (PV) diagnosis with emphasis on the joint role of diabatic heating feedback and midlatitude wave train. The SAH’s eastward extension features eastward propagation of a wave train across Eurasia. Among the wave train, the migration of weak high from the western flank of the Tibetan Plateau (TP) to the east of TP contributes to the SAH’s eastward extension at the early stage. When the SAH approaches its easternmost position, a strong negative PV (positive geopotential height) center prevails to the east of the TP at 200 hPa. The associated anomalies in diabatic heating and rainfall include the anomalous heating and above-normal rainfall over the South China Sea (SCS) and subtropical western Pacific occurring 12 days before the SAH’s easternmost stretch, and then anomalous cooling and below-normal rainfall over the southern foot of the TP and southern China and heating and above-normal rainfall over the northern TP and northern China a week later. The anomalous heating and ascending motion over the northern TP and northern China act to increase negative PV locally at 200 hPa. The cooling and descending induce positive PV over southern China. The north–south dipolar structure of PV anomaly with the climatological northerly flow is favorable to southward advection of a negative PV anomaly at 200 hPa. The anomalous heating over the SCS–western Pacific helps to develop a below-normal rainfall condition over southern China via inducing a lower-level anomalous cyclone over coastal region. These processes are conducive to the SAH’s eastward extension at its later stage.

Amphithalea ornata (Podalyrieae, Fabaceae), a rare new species from the Western Cape Province, South Africa

The new species, Amphithalea ornata, from the Worcester Valley in the Western Cape Province of South Africa, forms part of a group of four species with pedunculate inflorescences. Among these species it is most similar to Amphithalea spinosa but differs in its non-spinescent habit, shorter peduncles, and large, imbricate calyx lobes. A. ornata is restricted to the Breede River Valley where it occurs in Breede Shale Renosterveld at the southern foot of the Droëriviersberg, south of Worcester.

A Study of “kunigo”: the Todaiji Fuko that existed at the southern foot of Mt. Fuji, from the Nara to the Heian Eras

A Study of “kunigo”: the Todaiji Fuko that existed at the southern foot of Mt. Fuji, from the Nara to the Heian Eras

Increasing trends in heavy rain during the warm season in eastern Japan and its relation to moisture variation and topographic convergence

ABSTRACTUsing 34 years of hourly observational data collected from 1976 to 2009, the frequency of hourly heavy‐rain events during the warm season in eastern Japan was studied. A significant regional trend of heavy rain was not recognized over the area as a whole; however, stations with increasing trends in heavy rain were detected when daytime convergences towards the central mountains were strong. These stations were concentrated in a mesoscale region at the southern foot of the mountains in the northern Kanto district. In addition, the surface‐specific humidity (qsfc) in the mountainous region nearby also displayed an increasing trend, which was correlated with the increasing frequency of hourly heavy‐rain events. It is thought that the mechanism driving the recent increasing trend in heavy rain is an increase in qsfc in the mountainous region under the conditions that mesoscale convergence of surface winds developed.

The transition from Alboran to Algerian basins (Western Mediterranean Sea): Chronostratigraphy, deep crustal structure and tectonic evolution at the rear of a narrow slab rollback system

The eastern Alboran basin and its transition to the Algerian basin is a key area in the Mediterranean realm where controversial kinematic and geodynamical models are proposed. Models imply striking differences regarding the nature of the crust, the prevalence of brittle faulting and ductile shear, the origin of magmatism, the style of Miocene deformation and the driving mechanisms of the Alboran plate kinematics. Combining a new chronostratigraphic chart of the Alboran and Algerian basins based on the Habibas (HBB-1) core drill, deep seismic sections striking WSW-ENE and SSE-NNW, and potential field data, we re-assess the tectonic evolution that controlled the sedimentation and basement deformation of the westernmost limit of the Algerian basin and its transition with the Alboran domain. A WSW-directed extensional tectonic phase has shaped a stretched continental crust with typical tilted blocks along ∼100km from Burdigalian to Tortonian times, which is assumed to result from the WSW-directed migration of the Alboran block driven by a narrow slab rollback. In the Algerian basin, this event was followed by the emplacement of an oceanic-type crust. Potential field signatures of the deep basin as well as geometrical correlations with onland outcrops of inner zones suggest a minimum WSW-directed displacement of the Alboran terrane of ∼200km. At the southern foot of the Algerian basin, the continent-ocean transition is sharp and may result from the westward propagation of a slab tear at depth, forming two segments of STEP (Subduction-Transform Edge Propagator) margins. Our results support models of intense shear tractions at the base of an overriding plate governed by slab rollback-induced mantle flow. Finally, Messinian salt tectonics affected overlying deposits until today. A late Tortonian to Quaternary dominantly transpressive tectonic episode linked to the Africa-Iberia convergence post-dates previous events, deforming the whole margin.

富士山南麓の地下水水質，流動と窒素汚染

富士山南麓の地下水水質，流動と窒素汚染

Góry Hemos jako miejsce schronienia, baza wypadowa i punkt obserwacyjny w świetle bułgarsko-bizantyńskich zmagań zbrojnych okresu wczesnego średniowiecza

After the analysis of sources (coming mainly from the period of the 8th–9th centuries), the author of the article claims that still from the outset of the khanate on the lower Danube, Bulgarians made the Haemus Mountains (Stara Planina and Sredna Gora) a permanent protective barrier from behind which they could launch their attacks against the territory of Byzantine Thrace. The mountains functioned as an attack outpost (680/681, 763 and 792) and a convenient observation post, which was used to monitor the Byzantine military stationed both at the northern as well as southern foot of the range (708, 763, 811). The mountains were also used as a shelter to which the defeated Bulgarian troops would retreat (763, 811).

The interplay between adjacent Adige and Po alluvial systems and deltas in the late Holocene (Northern Italy)

The alluvial plain behind the southern Venice Lagoon, in northern Italy, is characterised by the presence of a complex network of alluvial ridges formed by the aggradation of channel deposits and natural levees. They are the geomorphological products of the interaction between the Adige and Po during the late Holocene. New geomorphological and stratigraphic data provided a detailed reconstruction of the evolution of the Po-Adige alluvial plain and allowed for defining the relation with the migration of delta lobes in the southern Venice Lagoon and near the Adriatic coast. Three cross sections (total of 28 manual boreholes) were obtained using a hand auger through two alluvial ridges built by the Adige River: the first two on the Conselve ridge (in the locations of Conselve and Santa Margherita, respectively) and the third across the modern Adige alluvial ridge. Radiocarbon dating was carried out on 9 peat samples. These data, coupled with a DTM, allowed the identification of a confluence between the Adige and Po during the Bronze Age. They also enabled the identification of the timing of major Adige and Po avulsions and the correlation with the 5.0-1.5 ka cal. BP development of a delta-mouth sedimentary system recognised in the southern Venice Lagoon. The results show that major avulsive events in the upstream tracts of the Po and Adige Rivers forced the migration of delta lobes. The delta system in the southern Venice Lagoon was fed by the Saline-Cona Po branch from about 4-3 ka cal. BP. This implies that the Po delta extended as far as 30 km north of the present-day river position. In this time frame, the Adige did not directly reach the sea, as it was a tributary of the Po at Agna. The northernmost lobe of the Po delta was thus fed by the sedimentary input of both the Po and Adige. The subsequent deactivation of the Saline-Cona Po branch through avulsion just upstream of Rovigo, around 3 ka cal. BP, led to a southwards shift of the Po delta system. The Adige still flowed through the Conselve ridge and kept its mouth in the same area. From 3 ka cal. BP to Roman times, the river constructed its own delta in the southern Venice Lagoon, prograding on the previous northern Po delta lobe. The Adige avulsion at Bonavigo during the early Middle Ages led to the abandonment of the Montagnana-Este-Conselve course long the southern foot of the Euganean Hills. As a consequence, the delta in the southern Venice Lagoon was also definitely abandoned and the Adige River started to construct another delta in its present-day position, about 15 km further to the south.