Hasil untuk "Physical geography"

Wulan Seizarwati, Naota Hanasaki, Saritha Padiyedath Gopalan et al.

Study region: Greater Jakarta in the Ciliwung-Cisadane River basin, Indonesia Study focus: Over 80 % of Jakarta's domestic water supply is imported from the Citarum River basin. Although this supply theoretically meets 65 % of current domestic water demand, approximately 46.67 % is lost through pipeline leakage. Given the large volumes involved, both leakage and inter-basin water transfer (IBWT) must be explicitly accounted in simulating Jakarta's hydrology and water resources. New hydrological insight for this region: This study presents a refined framework for assessing water allocation and groundwater management in urbanized basins by integrating domestic water supply leakage and IBWT into a distributed hydrological model. Simulations were conducted for the Ciliwung-Cisadane River basin, covering Jakarta, at 30-arcsecond (∼1 km) resolution for the 2004–2013 period. Two leakage mechanisms were modeled: (1) LEAK1, where leakage directly recharges groundwater, and (2) LEAK2, where leakage first infiltrates the soil layer. Multiple scenarios were analyzed, including a baseline condition, leakage influence, and IBWT effects. Results show that leakage contributes 35 %-41 % (95 % confidence interval) of total groundwater recharge, with higher contributions in urban areas. IBWT reduces Jakarta's domestic water deficit by 62.5 % and increases leakage volume by 12 %. The simulations also reveal an urban groundwater recycling process in which leaked water initially intended for domestic use is unintentionally reallocated to support industrial groundwater extraction. By explicitly incorporating these urban hydrological processes, this study provides more realistic, policy-relevant insights for sustainable water resources management.

Luis Alfredo Hernández-Vásquez, Mauricio Rojas-Ascensión, Sergio Reyes Rosas et al.

Urban river degradation demands remediation strategies that are both environmentally sustainable and technically feasible. This study evaluated the performance of Floating Treatment Wetlands (FTWs) vegetated with <i>Chrysopogon zizanioides</i> (vetiver) and incorporating four substrate configurations: leaf litter (LL), red volcanic rock (RVR), corn cobs (CC), and a composite mixture of all three, for the rehabilitation of the “Paseo de Los Ahuehuetes” River in Veracruz, Mexico. Over a 182-day monitoring period, in situ water quality parameters and plant growth responses were systematically assessed. The results indicate that substrate selection is a decisive design factor governing the establishment and development of <i>C. zizanioides</i> in FTWs. Among the substrates tested, LL exhibited the most favorable performance, achieving the highest plant survival (82%), enhanced shoot elongation (71.5 ± 12.1 cm), greater root development (49.7 ± 10.0 cm), and the highest relative growth rate (0.028 g g⁻¹ d⁻¹), with statistically significant differences (<i>p</i> < 0.05) compared to CC. Additionally, localized improvements in water quality within the FTW zone were observed, including an increase in dissolved oxygen (2.07%) and a reduction in total dissolved solids (5.65%), likely associated with intensified rhizospheric processes. Overall, these findings identify leaf litter as a low-cost, locally available, and environmentally sustainable substrate that enhances vetiver establishment in FTWs. The study provides practical, evidence-based criteria for the design of nature-based phytoremediation systems aimed at the restoration of urban river ecosystems.

Christos Tsakalidis, George E. Konidaris, Evangelia Tsoukala et al.

Dental wear analyses of extinct animals offer key insights into their dietary preferences and in turn contribute substantially to palaeoenvironmental reconstructions, leading to more accurate interpretations about past ecosystems. This study employs dental mesowear analysis on Pliocene and Pleistocene elephants and mammoths from several localities in Northern Greece (Ptolemais Basin, Mygdonia Basin, Drama Basin, and the Neapolis-Grevena Basin), aiming to classify them into three main dietary categories (browsers, mixed-feeders, grazers) and investigate potential niche partitioning. The method relies on documenting the wear pattern of molar surfaces through angle measurements on the enamel ridges, which reflect the average annual diet of the examined taxon and in turn the annual ecological conditions of the studied area. Prior to the palaeodietary study and in order to ensure the taxonomic attribution of the examined specimens, a taxonomic review was conducted which confirmed the presence of the mammoths <i>Mammuthus rumanus</i>, <i>Mammuthus meridionalis</i> (southern mammoth), and <i>Mammuthus trogontherii</i> (steppe mammoth), and the European straight-tusked elephant <i>Palaeoloxodon antiquus</i>. Dental mesowear results indicate a grazing diet for <i>M.</i> (cf.) <i>rumanus</i>, a mainly browsing diet for <i>M. meridionalis</i> but mixed-feeding to grazing for the subspecies <i>Mammuthus meridionalis vestinus</i>, a grazing one for <i>M. trogontherii</i>, and a wide diet spectrum for <i>P. antiquus</i>, including browsing, mixed-feeding and grazing, depending on the locality. This study expands our knowledge on the palaeoecology of Greek proboscideans and further highlights the importance of mesowear analysis on proboscidean teeth for palaeodietary and palaeoenviromental inferences.

Yujia Pei, Jiahong Liu, Jia Wang et al.

Study Region: Beijing Study focus: Urbanization has altered the processes of the hydrological cycle in cities, further affecting their precipitation extremes. This study utilizes Weather Research and Forecasting model (WRF) to investigate the sensitivity of extreme precipitation to urbanization, exemplified by analyzing the ''23·7'' extraordinary rainstorm in Beijing.Two comparative urban development scenarios (1980 and 2020) were designed, using the real underlying surface as the static geographic data for the WRF model. Furthermore, the reliability of the model results was validated through an analysis of the extreme precipitation event that occurred in July 2021, reinforcing the findings of this study. New Hydrological Insights for the Region: The simulated precipitation is well represented by using the underlying surface data post-urbanization. Furthermore, the study reveals that urbanization has augmented the total rainfall of two extreme precipitation events in Beijing: the ''23·7'' event and the event on July 12, 2021. Specifically, there was an increase of 19.1 mm and 7.1 mm, respectively, in the rainfall within the core urban area during these two extreme precipitation events, when comparing the underlying surface scenarios from 1980 to 2020. Analyzing the impact mechanism, weakened horizontal winds in the urban core prolong water vapor residence, altering land surface energy balance to boost temperature and convection, both contributing to urban-induced precipitation increase.

Ludovic Ravanel, Jacques Mourey, Lorig Tamian et al.

L’alpinisme est une pratique sportive qui dépend fortement des conditions des milieux physiques dans lesquels elle se développe. Les alpinistes doivent ainsi faire face à des aléas glaciaires et périglaciaires importants, tels que ceux qui affectent les deux principaux itinéraires d’ascension du mont Blanc (4808 m ; Alpes européennes occidentales) : les chutes de pierres dans le Grand Couloir de l’aiguille du Goûter sur la Voie Royale et les chutes de séracs sur le versant NNO du mont Blanc du Tacul sur l’itinéraire des Trois Monts. Les aléas dans ces deux secteurs ainsi que la fréquentation ont été mesurés grâce à un dispositif multicapteurs et à des acquisitions photographiques automatiques, respectivement. Sur le premier site, où l'on déplore une très forte accidentalité avec en moyenne 3,7 décès par an, 17 768 passages ont été comptabilisés au cours de l’été 2019 et 2 648 signaux sismiques ont été classés comme des chutes de pierres ayant affecté le Grand Couloir. Le risque de décès associé à ces chutes de pierres, dont la fréquence est dépendante des températures et de la présence d’eau liquide dans le terrain, serait de 1,7 × 10-4. Au Tacul, où en moyenne 0,6 décès se produit chaque année, 6 770 passages ont été relevés au cours de l’été 2017, ainsi que 31 chutes de séracs sans lien avec les températures. Le risque de décès y est de 8,3 × 10-5. L'aléa est également quantifié pour chacune des traces faites sur le versant glaciaire. Les résultats obtenus permettent de préciser les risques encourus par les alpinistes et de favoriser des stratégies de réduction des risques.

Jingzhao Feng, Yile Chen, Senyu Lou et al.

AbstractThe change in the land spatial structure affects regional development and stability. In the context of the construction of the Guangdong-Hong Kong-Macao Greater Bay Area, studying the spatial structure changes in its important cities will contribute to the coordinated development of the region. This study uses spatial analysis and coupling models to explore the basic characteristics and evolutionary trends of the land spatial structure in Zhongshan city in 2000, 2011, 2022, and 2035. Through research, it is found that (1) in general, the urban space is divided into different geometric forms by the water network system. The spatial structure of living land is ‘fragmentation-aggregation-aggregation and fragmentation’. (2) Ecological land is concentrated in the southeast and remained relatively stable. Productive land accounts for the largest proportion in Northeast China, becoming the main area of agricultural development. (3) From 2022 to 2035, the area of productive land will increase in different ranges under four scenarios, and the area of productive land will increase the fastest under the urbanization development scenario (UDS). (4) The ecological land area increases only in the ecological protection scenario (EPS), and the area decreases in the other three scenarios. An increase in construction land area occurs in the urbanization development scenario (UDS) and nature development scenario (NDS). (5) The habitat quality of Zhongshan city showed a significant decline from 2000 to 2022. In 2035, the habitat quality will significantly improve in the ecological protection scenario (EPS) and sustainable development scenario (SDS) scenarios, and the ecological regions in Southeast China will be significantly clustered and expanded.

Jinwook Lee, Chulsang Yoo

Most empirical formulae for the basin concentration time (Tc) and storage coefficient (K) focus on estimating the representative values under the ordinary condition, with their return period being a maximum of 100–200 years. Under more extreme conditions, those parameters should be modified to consider faster velocity conditions. The main objective of this study is to examine the possibility of determining these parameters corresponding to the given peak velocity (vp) at the basin outlet. Two issues are involved in this problem; one is whether Tc can be fully expressed by vp, while the other is whether K is still linearly proportional to Tc under extreme conditions. In this study, these two issues are resolved by the theoretical review of these parameters, as well as an analysis of the rainfall–runoff events collected at the Chungju Dam basin, Korea. It is observed that as vp increases, Tc and K decrease. Their relationship is close to inverse but in linear proportion. That is, strong linear relationships are found among Tc, K, and vp. As a result, the ratio of K to Tc is found to be almost identical, regardless of vp. This ratio at a basin can be assumed as a basin characteristic that is unchanged, regardless of the size of rainfall events. HIGHLIGHTS Strong linear relationships at the basin outlet are found among the basin concentration time, storage coefficient, and peak velocity.; The ratio of the storage coefficient to the concentration time is found to be almost identical, regardless of the peak velocity.; The ratio of the storage coefficient to the concentration time can be assumed as an unchanged basin characteristic, regardless of the size of rainfall events.;

Hugo Martins, Paulo Carvalho, Nuno Almeida

O conhecimento sobre o perfil dos turistas é fundamental para que as entidades gestoras de destinos e operadores turísticos possam definir, implementar e monitorizar estratégias adequadas para captar novos visitantes, fidelizar turistas e reinventar constantemente a oferta em função das características da componente de mercado associada à procura. É assim que se justifica a presente investigação, centrada no Parque Nacional da Peneda-Gerês (PNPG) e suportada em inquéritos por questionário aos visitantes que utilizaram unidades de alojamento, em período pré-pandemia, entre junho e outubro. Apresenta-se uma caracterização social, económica e profissional dos turistas, bem como os resultados inerentes às suas motivações e expectativas em relação a este destino turístico consagrado de Portugal, com especial incidência nos segmentos de natureza e de touring cultural e paisagístico. As principais conclusões da pesquisa configuram informação da maior relevância não só para os agentes locais da atividade turística como para as entidades com responsabilidade no planeamento e gestão do turismo regional e nacional.

Irene Marzolff, Mario Kirchhoff, Robin Stephan et al.

Monitoring woody cover by remote sensing is considered a key methodology towards sustainable management of trees in dryland forests. However, while modern very high resolution satellite (VHRS) sensors allow woodland mapping at the individual tree level, the historical perspective is often hindered by lack of appropriate image data. In this first study employing the newly accessible historical HEXAGON KH-9 stereo-panoramic camera images for environmental research, we propose their use for mapping trees in open-canopy conditions. The 2–4 feet resolution panchromatic HEXAGON satellite photographs were taken 1971–1986 within the American reconnaissance programs that are better known to the scientific community for their lower-resolution CORONA images. Our aim is to evaluate the potential of combining historical CORONA and HEXAGON with recent WorldView VHRS imagery for retrospective woodland change mapping on the tree level. We mapped all trees on 30 1-ha test sites in open-canopy argan woodlands in Morocco in the field and from the VHRS imagery for estimating changes of tree density and size between 1967/1972 and 2018. Prior to image interpretation, we used simulations based on unmanned aerial system (UAS) imagery for exemplarily examining the role of illumination, viewing geometry and image resolution on the appearance of trees and their shadows in the historical panchromatic images. We show that understanding these parameters is imperative for correct detection and size-estimation of tree crowns. Our results confirm that tree maps derived solely from VHRS image analysis generally underestimate the number of small trees and trees in clumped-canopy groups. Nevertheless, HEXAGON images compare remarkably well with WorldView images and have much higher tree-mapping potential than CORONA. By classifying the trees in three sizes, we were able to measure tree-cover changes on an ordinal scale. Although we found no clear trend of forest degradation or recovery, our argan forest sites show varying patterns of change, which are further analysed in Part B of our study. We conclude that the HEXAGON stereo-panoramic camera images, of which 670,000 worldwide will soon be available, open exciting opportunities for retrospective monitoring of trees in open-canopy conditions and other woody vegetation patterns back into the 1980s and 1970s.

A. Joseph, D. Phillips

G. Petts

Shingo Sakai, Ruako Takatori, Mika Nomura et al.

Abstract Background Facial skin care (FSC) is an important routine for Japanese women. Hand motions during FSC physically affect psychological state. However, it is very difficult to evaluate hand motions during personal and complex FSC. The objective of this study was to find out objective and quantitative parameters for hand motions during facial skin care (FSC). Women who enjoy and soothe during FSC (Enjoyment group (E group), n = 20) or not (non-enjoyment group (NE group), n = 19) were recruited by an advance questionnaire. The same lotion, emulsion, and cream were provided to all subjects, and they used sequentially in the same way as the women’s daily FSC. The motion of the marker on the back side of the right middle finger during FSC was tracked by a motion capture system. The heart rate variability (HRV) was also measured before and after FSC for evaluating psychological effect. Results The averaged acceleration (Avg. ACC), approximate entropy (ApEn), and power law scaling exponent (Rest γ) of the cumulative duration of slow motion from the sequential data of acceleration were evaluated. Compared to the NE group, the E group showed a lower Avg. ACC when using emulsion (p = 0.005) and cream (p = 0.007), a lower ApEn when using emulsion (p = 0.003), and a lower Rest γ (p = 0.024) when using all items, suggesting that compared to the NE group, the E group had more tender and regular motion, and sustainable slow motions, especially in the use of emulsion. In the E group, the low/high-frequency component of HRV decreased significantly after FSC, suggesting suppression of sympathetic activity (p = 0.045). NE group did not. For all subjects, ApEn and Rest γ showed significantly positive correlation with the increase in the low/high-frequency component of HRV after FSC (p < 0.01). ApEn showed significantly negative correlation with the increase in the high-frequency component of HRV after FSC (p < 0.05). Avg. ACC did not show significant correlation with them. These results suggested that the behavior of FSC influences the autonomic nerve system. Conclusions ApEn and Rest γ are useful parameters for evaluating quality of hand motions during FSC.

K. Fujita, H. Inoue, T. Izumi et al.

Coseismic avalanches and rockfalls, as well as their simultaneous air blast and muddy flow, which were induced by the 2015 Gorkha earthquake in Nepal, destroyed the village of Langtang. In order to reveal volume and structure of the deposit covering the village, as well as sequence of the multiple events, we conducted an intensive in situ observation in October 2015. Multitemporal digital elevation models created from photographs taken by helicopter and unmanned aerial vehicles reveal that the deposit volumes of the primary and succeeding events were 6.81 ± 1.54  ×  10⁶ and 0.84 ± 0.92  ×  10⁶ m³, respectively. Visual investigations of the deposit and witness statements of villagers suggest that the primary event was an avalanche composed mostly of snow, while the collapsed glacier ice could not be dominant source for the total mass. Succeeding events were multiple rockfalls which may have been triggered by aftershocks. From the initial deposit volume and the area of the upper catchment, we estimate an average snow depth of 1.82 ± 0.46 m in the source area. This is consistent with anomalously large snow depths (1.28–1.52 m) observed at a neighboring glacier (4800–5100 m a.s.l.), which accumulated over the course of four major snowfall events between October 2014 and the earthquake on 25 April 2015. Considering long-term observational data, probability density functions, and elevation gradients of precipitation, we conclude that this anomalous winter snow was an extreme event with a return interval of at least 100 years. The anomalous winter snowfall may have amplified the disastrous effects induced by the 2015 Gorkha earthquake in Nepal.

Abdoul Aziz Gning, Philippe Orban, Julie Gesels et al.

Study region: Senegal River Delta. Study focus: The Senegal River Delta is a strategic region for the development of irrigated agriculture. Despite a Sahelian climatic context, the management of the river with dams ensures water availability throughout the year. With the intensification of agriculture, degradation of cultivated soils is observed, mostly linked to the existence of a shallow salty aquifer. In this context, regional surveys were performed to characterize groundwater–surface water interactions and to identify the impact of artificial river management and agricultural intensification on the evolution of groundwater dynamics and chemistry. New hydrological insights for the region: Results show that groundwater far away from rivers and outside irrigated plots has evolved from marine water to brines under the influence of evapotranspiration. Near rivers, salinity of groundwater is lower than seawater and groundwater mineralization seems to evolve in the direction of softening through cationic exchanges related to permanent contact with fresh water. Despite large volumes of water used for rice cultivation, groundwater does not show any real softening trend in the cultivated parcels. Results show that the mechanisms that contribute to repel salt water from the sediments correspond to a lateral flush near permanent surface water streams and not to vertical drainage and dilution with rainfall or irrigation water. It is however difficult to estimate the time required to come back to more favorable conditions of groundwater salinity.

Artem Kouchinsky

The following specimen/sample accession numbers and accompanying information are updated

Achille C. Varzi, Barry Smith

Kate Shannon, Melanie L. A. Rusch, J. Shoveller et al.

Erika Maria da Silva Sousa, Edenilson Andrade Ferreira, Maria Valdirene Araújo Rocha

O presente trabalho representa uma tentativa de análise das alterações da área do Balneário Curva São Paulo, localizado na zona sudeste da cidade de Teresina, capital do Estado do Piauí. O artigo tem o objetivo de identificar as principais alterações causadas pela intervenção antrópica na área de estudo ao longo do tempo, bem como propor novas formas de intervenção mais adequadas, utilizando como recursos metodológicos imagens de satélite retrospectivas adquiridas através do software gratuito Google Earth, fotografias retiradas pelos autores e relatos dos moradores das áreas circundantes ao Balneário Curva São Paulo. Onde foi possível concluir que a ação antrópica agiu desde a implantação do balneário, tanto no desmatamento das áreas verdes quanto na poluição das águas do Rio Poti.

S. Ousley, R. Jantz, Donna Freid

庄子 貞雄, 南條 正巳, R. Dahlgren