Journal articles: 'Land-water interfaces'

1

Wetzel, Robert G. "Land-water interfaces: Metabolic and limnological regulators." SIL Proceedings, 1922-2010 24, no. 1 (December 1990): 6–24. http://dx.doi.org/10.1080/03680770.1989.11898687.

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Ding, Lilian, Qiyao Li, Jianjun Tang, Jiangfei Wang, and Xin Chen. "Linking Land Use Metrics Measured in Aquatic–Terrestrial Interfaces to Water Quality of Reservoir-Based Water Sources in Eastern China." Sustainability 11, no. 18 (September 5, 2019): 4860. http://dx.doi.org/10.3390/su11184860.

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The effects of anthropogenic land use on the water quality of reservoir-based water sources are understudied. We trained a self-organizing map (SOM) to measure the spatial pattern of nutrients over the course of a year in 61 reservoirs located in eastern China. In the linear regression model and one-way analyses of variance, we found that water quality was influenced by period of the year (flood, low, and normal periods based on rainfall conditions) and reservoir altitude (plains vs. mountains). Our results indicated that land use metrics measured in aquatic–terrestrial interfaces significantly influenced the water quality of reservoirs. The land use intensity (LUI) and the proportion of construction land had a positive correlation with ammonia nitrogen (NH3-N) and chemical oxygen demand (CODMn) concentrations, and redundancy analysis indicated that the percent of landscape (PLAND) represented by construction land was positively correlated with CODMn, NH3-N, total phosphorus (TP), and total nitrogen (TN) concentrations. The proportion of cropland was not correlated with any water quality property except for CODMn concentration. The total explained variance for water quality was highest when the scale was large (the area defined by a 1500 m radius around the reservoir), indicating that management which ensures water safety should be carried out at this scale.

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Ilgen, Anastasia G., Nadine Kabengi, Kevin Leung, Poorandokht Ilani-Kashkouli, Andrew W. Knight, and Lourdes Loera. "Defining silica–water interfacial chemistry under nanoconfinement using lanthanides." Environmental Science: Nano 8, no. 2 (2021): 432–43. http://dx.doi.org/10.1039/d0en00971g.

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B�nziger, Ruth. "A comparative study of the zoobenthos of eight land-water interfaces (Lake of Geneva)." Hydrobiologia 300-301, no. 1 (March 1995): 133–40. http://dx.doi.org/10.1007/bf00024455.

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Liang, Gang, Xinglei Zhao, Jianhu Zhao, and Fengnian Zhou. "Feature Selection and Mislabeled Waveform Correction for Water–Land Discrimination Using Airborne Infrared Laser." Remote Sensing 13, no. 18 (September 11, 2021): 3628. http://dx.doi.org/10.3390/rs13183628.

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The discrimination of water–land waveforms is a critical step in the processing of airborne topobathy LiDAR data. Waveform features, such as the amplitudes of the infrared (IR) laser waveforms of airborne LiDAR, have been used in identifying water–land interfaces in coastal waters through waveform clustering. However, water–land discrimination using other IR waveform features, such as full width at half maximum, area, width, and combinations of different features, has not been evaluated and compared with other methods. Furthermore, false alarms often occur when water–land discrimination in coastal areas is conducted using IR laser waveforms because of environmental factors. This study provides an optimal feature for water–land discrimination using an IR laser by comparing the performance of different waveform features and proposes a dual-clustering method integrating K-means and density-based spatial clustering applications with noise algorithms to improve the accuracy of water–land discrimination through the clustering of waveform features and positions of IR laser spot centers. The proposed method is used for practical measurement with Optech Coastal Zone Mapping and Imaging LiDAR. Results show that waveform amplitude is the optimal feature for water–land discrimination using IR laser waveforms among the researched features. The proposed dual-clustering method can correct mislabeled water or land waveforms and reduce the number of mislabeled waveforms by 48% with respect to the number obtained through traditional K-means clustering. Water–land discrimination using IR waveform amplitude and the proposed dual-clustering method can reach an overall accuracy of 99.730%. The amplitudes of IR laser waveform and the proposed dual-clustering method are recommended for water–land discrimination in coastal and inland waters because of the high accuracy, resolution, and automation of the methods.

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Rood, Stewart B., Michael L. Scott, Mark Dixon, Eduardo González, Christian O. Marks, Patrick B. Shafroth, and Malia A. Volke. "Ecological Interfaces between Land and Flowing Water: Themes and Trends in Riparian Research and Management." Wetlands 40, no. 6 (December 2020): 1801–11. http://dx.doi.org/10.1007/s13157-020-01392-4.

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Bolpagni, Rossano, Alex Laini, Tiziana Mutti, Pierluigi Viaroli, and Marco Bartoli. "Connectivity and habitat typology drive CO2 and CH4 fluxes across land-water interfaces in lowland rivers." Ecohydrology 12, no. 1 (September 14, 2018): e2036. http://dx.doi.org/10.1002/eco.2036.

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Dezső, József, Szabolcs Czigány, Gábor Nagy, Ervin Pirkhoffer, Marcin Słowik, and Dénes Lóczy. "Monitoring soil moisture dynamics in multilayered Fluvisols." Bulletin of Geography. Physical Geography Series 16, no. 1 (June 18, 2019): 131–46. http://dx.doi.org/10.2478/bgeo-2019-0009.

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Abstract The identification of drought-sensitive areas (DSAs) in floodplain Fluvisols of high textural pedodiversity is crucial for sustainable land management purposes. During extended drought periods moisture replenishment is only available by capillary rise from the groundwater. However, moisture flux is often hindered by capillary barriers in the interface between layers of contrasting textures. The results of HYDRUS-1D simulations run on multilayered soil profiles were integrated into textural maps to determine the spatial distribution of water dynamics on the floodplain of the Drava River (SW Hungary). Model runs and field data revealed limited moisture replenishment by capillary rise when both contrasting textural interfaces and sandy layers are present in the profile. By implementing these textural and hydraulic relations, a drought vulnerability map (DSA map) of the operational area of the Old Drava Programme (ODP) was developed. According to the spatial distribution of soils of reduced capillary rise, 52% of the ODP area is likely threatened by droughts. Our model results are adaptable for optimisation of land- and water-management practices along the floodplains of low-energy and medium-sized rivers under humid continental and maritime climates.

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Chu, D. K. Y. "Government Policies, Economic Development, and Possible Environmental Effects at the Land-Water Interfaces of Guangdong Province, China." Marine Resource Economics 3, no. 1 (January 1986): 29–44. http://dx.doi.org/10.1086/mre.3.1.42628916.

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Wahren, A., K. Berkhoff, S. Herrmann, and K. H. Feger. "Building an integrated modeling framework for assessing land-use change and its consequences for areal water balance in mountainous Southwest China." Advances in Geosciences 27 (September 7, 2010): 71–77. http://dx.doi.org/10.5194/adgeo-27-71-2010.

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Abstract. The opening up of China's industry towards market orientation has a distinct impact on natural resources as well as on social structures. The example of rubber introduction in Yunnan province (SW China) shows the mutual interdependencies between economy, natural resources, and social structures. We assess the impacts of rubber introduction and possible development paths in the study area. An integrated modeling framework (NabanFrame) is developed for the catchment of the Naban River (size 270 km2), a tributary to the Mekong River. NabanFrame comprises an agro-economic, ecological, and social model. Altogether they interact with a land-use change model via defined interfaces. Effects on the water cycle are considered by additionally integrating the spatially distributed rainfall-runoff and water balance model AKWA-M® in the model framework. Therefore, a reasonable parameterization is needed to assess the land-use changes on areal water fluxes. The authors conclude that the chosen hydrological model is able to assess the impacts of land conversion (from forest to rubber plantations) on catchment hydrology and address further adaptations to be implemented in the hydrological model.

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Cherry, Julia A., Amelia K. Ward, and G. Milton Ward. "The dynamic nature of land-water interfaces: changes in structure and productivity along a water depth gradient in the Talladega Wetland Ecosystem." SIL Proceedings, 1922-2010 30, no. 6 (January 2009): 977–80. http://dx.doi.org/10.1080/03680770.2009.11902282.

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Sulzberger, B., A. T. Austin, R. M. Cory, R. G. Zepp, and N. D. Paul. "Solar UV radiation in a changing world: roles of cryosphere–land–water–atmosphere interfaces in global biogeochemical cycles." Photochemical & Photobiological Sciences 18, no. 3 (2019): 747–74. http://dx.doi.org/10.1039/c8pp90063a.

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Lincoln, B. J., T. R. E. Simpson, and J. L. Keddie. "Water vapour sorption by the pedal mucus trail of a land snail." Colloids and Surfaces B: Biointerfaces 33, no. 3-4 (February 2004): 251–58. http://dx.doi.org/10.1016/j.colsurfb.2003.10.013.

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14

Moss, Timothy, and Frank Hüesker. "Politicised nexus thinking in practice: Integrating urban wastewater utilities into regional energy markets." Urban Studies 56, no. 11 (November 8, 2017): 2225–41. http://dx.doi.org/10.1177/0042098017735229.

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Infrastructures are key interfaces of urban resource use, connecting production to consumption, cities to their hinterland and energy to water and land use. They have, however, received scant attention in debates on nexus thinking in general, and the urban nexus in particular. Drawing on an emergent critical literature on the nexus in urban studies and science and technology studies, this article examines practices of (attempted) inter-sectoral infrastructure integration at the interface of urban wastewater treatment and regional energy provision in Germany. It analyses the nexus approaches and experiences of eight German cities / city-regions as so-called ‘flexibility providers’ in regional energy markets for electricity, gas and heating. It demonstrates how the practices of wastewater utilities operating in energy markets involve far more than technical adaptation, requiring in addition a major reordering of existing material, spatial and institutional configurations to both wastewater and energy systems. This is proving a deeply political process with important implications for our understanding of socio-technical transitions at the water-energy nexus.

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Yang, Peng, Jun Xia, Chesheng Zhan, Xuejuan Chen, Yunfeng Qiao, and Jie Chen. "Separating the impacts of climate change and human activities on actual evapotranspiration in Aksu River Basin ecosystems, Northwest China." Hydrology Research 49, no. 6 (July 6, 2018): 1740–52. http://dx.doi.org/10.2166/nh.2018.136.

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Abstract Separating the impacts of climate change and human activity on actual evapotranspiration (ET) is important for reducing comprehensive risk and improving the adaptability of water resource systems. In this study, the spatiotemporal distribution of actual ET in the Aksu River Basin, Northwest China, during the period 2000–2015 was evaluated using the Vegetation Interfaces Processes model and Moderate Resolution Imaging Spectroradiometer-Normalized Difference Vegetation Index. The impact of climate change and human activity on actual ET were separated and quantified. The results demonstrated that: (1) the annual pattern of actual ET per pixel exhibited the highest values for arable land (average 362.4 mm/a/pixel), followed by forest land and grassland (average of 159.6 and 142.8 mm/a/pixel, respectively). Significant increasing linear trends (p < 0.05) of 3.2 and 1.8 mm/a were detected in the arable land and forest land time series, respectively; (2) precipitation was the most significant of the selected climate factors (precipitation, average temperature, sunshine duration, and wind speed) for all ecosystems. The second most significant was wind speed; (3) human activity caused 89%, 98%, and 80% of the changes in actual ET of forest, grass, and arable land, respectively, while climate change caused 11%, 2%, and 20% of the changes in actual ET, in the Aksu River Basin during 2000–2015.

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Kogelbauer, I., and W. Loiskandl. "Characterization of sediment layer composition in a shallow lake: from open water zones to reed belt areas." Hydrology and Earth System Sciences 19, no. 3 (March 19, 2015): 1427–38. http://dx.doi.org/10.5194/hess-19-1427-2015.

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Abstract. Lake sediment characterization, a prerequisite for the vulnerability assessment of lake ecosystems, demands reliable in situ methods for the characterization of the sediment layer composition. A unified characterization of lake sediments within lake ecotopes (open water, open water patches within the reed, and the reed) is still a challenge. Each ecotope is covered by different classical scientific disciplines (hydrography and terrestrial remote sensing to soil physics) with their specific characterization methods. Recently, a complementary tool that bridges the gap between land and hydrographic surveying methods was introduced. It is a non-acoustic device that combines two soil physical sensors (a capacitive sensor and a cone penetrometer) and GNSS-positioning in a measuring system (CSPS). The CSPS enables rapid in situ delineation of water–mud–consolidated lakebed interfaces. The system was successfully applied across ecotopes at the Neusiedler See, a well-mixed shallow lake rich in fine-grained sediments. The geo-referenced vertical CSPS profiles show ecotope-specific layer composition. The effects of wind-induced turbidity, particle size, and electrical conductivity were analysed. The water–mud interface was precisely delineated at the open water due to a persistent high water content gradient, equivalent to a lutocline. The penetration resistance (PR) for open water showed either a shallow and highly compacted consolidated lakebed or a consolidated lakebed with a partially compacted layer above, while in the reed the PR smoothly increased until reaching the deepest penetration depths.

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Kogelbauer, I., and W. Loiskandl. "Characterization of sediment layer composition in a shallow lake: from open water zones to reed belt areas." Hydrology and Earth System Sciences Discussions 11, no. 11 (November 13, 2014): 12627–57. http://dx.doi.org/10.5194/hessd-11-12627-2014.

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Abstract. Lake sediment characterization, a pre-requirement for the vulnerability assessment of lake ecosystems, demands reliable in situ methods for the characterization of the sediment layer composition. A unified characterization of lake sediments within different lake ecotopes (open water, open water patches within the reed, and the reed) is still a challenge. Each ecotope is covered by different classical scientific disciplines (hydrography and terrestrial remote sensing to soil physics) with their specific characterization methods. However, a complementary tool that bridges the gap between land- and hydrographic surveying methods is still missing. Therefore a combination of soil physical sensors (a capacitive sensor and a cone penetrometer) in a measuring system (CSPS) was introduced. CSPS is a non-acoustic device for the rapid in situ delineation of water-mud-consolidated lakebed interfaces. The system was successfully applied across the different ecotopes at the Neusiedler See, a well-mixed shallow lake rich in fine-grained sediments. The geo-referenced vertical CSPS profiles show ecotope-specific layer composition. The effect of wind induced turbidity, particle size, and electrical conductivity were analysed. The water–mud interface was precisely delineated at the open water due to a persistent high water content gradient, equivalent to a lutocline. The penetration resistance for open water showed either a shallow and highly-compacted consolidated lakebed or a consolidated lakebed with a partially compacted layer above; while in the reed the penetration resistance smoothly increased until reaching the deepest penetration depths.

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Zhang, Dejian, Wenjie Fu, Qiaoying Lin, and Xingwei Chen. "WOF-SWAT: A Web-Based Open-Source Framework for Investigating the Hydrological Impacts of Climate Change and Human Activities Through Online Simulation and Visualization of SWAT Models." ISPRS International Journal of Geo-Information 8, no. 9 (August 23, 2019): 368. http://dx.doi.org/10.3390/ijgi8090368.

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This study developed a web-based open-source framework based on the Soil and Water Assessment Tool (SWAT), named WOF-SWAT (web-based open-source framework for SWAT), to investigate individual and combined impacts of climate change, land use change, and point-source pollutants on watershed-scale hydrological and chemical processes. The architecture, workflows, interfaces, and key processes of WOF-SWAT are described and discussed. Using a previously developed well-calibrated hydrological model of the Jinjiang River basin, four scenarios were simulated in WOF-SWAT and other traditional desktop-based tools (i.e., ArcSWAT and SWAT-CUP) to examine the credibility, efficiency, and functionality of WOF-SWAT. The results show that, in combination with a well-calibrated watershed model, WOF-SWAT is sufficiently sound and reasonable to investigate individual and combined impacts of climate change, land use change, and point-source pollutants. We thus conclude that WOF-SWAT can be used as a substitute for other tools to carry out similar tasks in a web-based environment while providing more user-friendly interfaces, accessibility, and efficiency. We also discuss ongoing and possible future efforts to develop WOF-SWAT into a fully-fledged watershed research and management framework.

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Abdulkadir Gidado, Kabir, Mohd Khairul Amri Kamarudin, Nik Ahmad Firdausaq, Aliyu Muhammad Nalado, Ahmad Shakir Mohd Saudi, Muhammad Hafiz Md Saad, and Salisu Ibrahim. "Analysis of Spatiotemporal Land Use and Land Cover Changes using Remote Sensing and GIS: A Review." International Journal of Engineering & Technology 7, no. 4.34 (December 13, 2018): 159. http://dx.doi.org/10.14419/ijet.v7i4.34.23850.

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The land-use and land-cover (LULC) pattern of an area is an outcome of natural and socio-economic factors and their use spatially by man; this LULC varies from the forest, water body, agricultural land and so on. Remote Sensing (RS) and Geographical Information System (GIS) studies have predominantly focused on providing the technical knowledge of, where, and the type of LULC change that has occurred and its impacts on man and the environment. Knowledge about LULC changes is essential for understanding the relationships and interfaces between humans and the natural environment. The purpose of this article is to review the previous studies of the spatiotemporal LULC changes. However, thirty (30) articles were reviewed from 2011 to 2017. However, these articles studied the LULC, classification, changes and change detection analysis, using different methods and software of RS and G.I.S. The finding shows that these articles have overall accuracy assessment ranges from 75% to 95% validations. Also, supervised classification in Maximum Likelihood Algorithm method was mostly employed for the LULC classification. Moreover, these reviewed articles confirmed that LULC changes are imminent as a result of both natural and human factors which lead to increase and decrease of one LULC cover to another. Therefore proper monitoring of LULC changes when applied help the relevant government bodies, agencies and environmental managers utilise the environment to the fullest.

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Han, Shengsheng, Suxia Liu, Shi Hu, Xianfang Song, and Xingguo Mo. "Evapotranspiration on Natural and Reclaimed Coral Islands in the South China Sea." Remote Sensing 13, no. 6 (March 15, 2021): 1110. http://dx.doi.org/10.3390/rs13061110.

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Studies of evapotranspiration on remote tropical coral islands are important to explore and sustain scarce freshwater resources. However, there is a significant knowledge gap between research to evaluate evapotranspiration based on remote sensing methods and the influences of different land use types on water dynamics on reclaimed coral islands. This study applied the remote-sensing-based Vegetation Interfaces Processes (VIP-RS) model to estimate actual evapotranspiration (ETa) on Zhaoshu Island, Yongxing Island, and Yongshu Island in the South China Sea from 2016 to 2019. The results showed that the average annual ETa of Zhaoshu Island, Yongxing Island, and Yongshu Island was 685 mm, 530 mm, and 210 mm, respectively. Annual transpiration (Ec) and soil evaporation (Es) exhibited similar patterns on the natural islands; however, Es controlled the water consumption on the reclaimed islands. Water dynamics exhibited seasonal fluctuations due to the uneven distribution of precipitation (PRP). However, ETa of the natural islands was higher than PRP in the dry season, indicating vegetation has to absorb water from the groundwater to sustain growth. The results also agreed with the analysis of dominant driving factors based on partial correlation analysis, which demonstrated that the Normalized Difference Vegetation Index (NDVI) is the most important factor that influences ETa, while relative humidity (RH) controlled the bare land or sparsely vegetated areas on the reclaimed islands. The setting of different land use types showed that vegetation and built-up or hardened roads took control of evapotranspiration and rainwater collection, respectively, which play important roles in water dynamics on corals islands. The evaluation of ETa based on a remote-sensing-based model overcame the difficulty in fieldwork observation, which improves the certainty and accuracy at a spatial scale. In addition, it gave us a new reference to protect and manage scarce freshwater resources properly.

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Mulsow, C., R. Kenner, Y. Bühler, A. Stoffel, and H. G. Maas. "SUBAQUATIC DIGITAL ELEVATION MODELS FROM UAV-IMAGERY." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2 (May 30, 2018): 739–44. http://dx.doi.org/10.5194/isprs-archives-xlii-2-739-2018.

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The paper presents an approach for the generation of digital elevation models (DEMs) of underwater areas from aerial images. Standard software-products do not provide the possibility to measure correctly through refractive interfaces, such as water. Existing solutions for that problem are based on oriented images and known water levels with the DEM points determined by forward intersection based on reconstructed image ray paths (ray tracing). In this article we present an integrated procedure for image orientation as well as DEM mass point determination from aerial imagery containing both land and underwater areas. The proof of concept was done by capturing UAV imagery of shallow water areas of a high-alpine lake in the Swiss alps. In the paper the processed dataset will be presented. Furthermore, the extraction and matching of image-points observed through water are discussed. The accuracy potential as well as practical limitations of processing multimedia-data are analysed.

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Wang, Yunfei, Yijian Zeng, Lianyu Yu, Peiqi Yang, Christiaan Van der Tol, Qiang Yu, Xiaoliang Lü, Huanjie Cai, and Zhongbo Su. "Integrated modeling of canopy photosynthesis, fluorescence, and the transfer of energy, mass, and momentum in the soil–plant–atmosphere continuum (STEMMUS–SCOPE v1.0.0)." Geoscientific Model Development 14, no. 3 (March 11, 2021): 1379–407. http://dx.doi.org/10.5194/gmd-14-1379-2021.

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Abstract. Root water uptake by plants is a vital process that influences terrestrial energy, water, and carbon exchanges. At the soil, vegetation, and atmosphere interfaces, root water uptake and solar radiation predominantly regulate the dynamics and health of vegetation growth, which can be remotely monitored by satellites, using the soil–plant relationship proxy – solar-induced chlorophyll fluorescence. However, most current canopy photosynthesis and fluorescence models do not account for root water uptake, which compromises their applications under water-stressed conditions. To address this limitation, this study integrated photosynthesis, fluorescence emission, and transfer of energy, mass, and momentum in the soil–plant–atmosphere continuum system, via a simplified 1D root growth model and a resistance scheme linking soil, roots, leaves, and the atmosphere. The coupled model was evaluated with field measurements of maize and grass canopies. The results indicated that the simulation of land surface fluxes was significantly improved by the coupled model, especially when the canopy experienced moderate water stress. This finding highlights the importance of enhanced soil heat and moisture transfer, as well as dynamic root growth, on simulating ecosystem functioning.

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Rahlff, Janina, Helge-Ansgar Giebel, Christian Stolle, Oliver Wurl, Alexander J. Probst, and Daniel P. R. Herlemann. "Overlooked Diversity of Ultramicrobacterial Minorities at the Air-Sea Interface." Atmosphere 11, no. 11 (November 10, 2020): 1214. http://dx.doi.org/10.3390/atmos11111214.

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Members of the Candidate phylum Patescibacteria, also called Candidate Phyla Radiation (CPR), are described as ultramicrobacteria with limited metabolic capacities. Wide diversity and relative abundances up to 80% in anaerobic habitats, e.g., in groundwater or sediments are characteristic for Candidatus Patescibacteria. However, only few studies exist for marine surface water. Here, we report the presence of 40 patescibacterial candidate clades at air-sea interfaces, including the upper water layer, floating foams and the sea-surface microlayer (SML), a < 1 mm layer at the boundary between ocean and atmosphere. Particle-associated (>3 µm) and free-living (3–0.2 µm) samples were obtained from the Jade Bay, North Sea, and 16S rRNA (gene) amplicons were analyzed. Although the abundance of Cand. Patescibacteria representatives were relatively low (<1.3%), members of Cand. Kaiserbacteria and Cand. Gracilibacteria were found in all samples. This suggests profound aerotolerant capacities of these phylogenetic lineages at the air-sea interface. The presence of ultramicrobacteria in the >3 µm fraction implies adhesion to bigger aggregates, potentially in anoxic niches, and a symbiotic lifestyle. Due to their small sizes, Cand. Patescibacteria likely become aerosolized to the atmosphere and dispersed to land with possible implications for affecting microbial communities and associated processes in these ecosystems.

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Pullar, D. "Incorporating level set methods in Geographical Information Systems (GIS) for land-surface process modeling." Advances in Geosciences 4 (August 9, 2005): 17–22. http://dx.doi.org/10.5194/adgeo-4-17-2005.

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Abstract. Land-surface processes include a broad class of models that operate at a landscape scale. Current modelling approaches tend to be specialised towards one type of process, yet it is the interaction of processes that is increasing seen as important to obtain a more integrated approach to land management. This paper presents a technique and a tool that may be applied generically to landscape processes. The technique tracks moving interfaces across landscapes for processes such as water flow, biochemical diffusion, and plant dispersal. Its theoretical development applies a Lagrangian approach to motion over a Eulerian grid space by tracking quantities across a landscape as an evolving front. An algorithm for this technique, called level set method, is implemented in a geographical information system (GIS). It fits with a field data model in GIS and is implemented as operators in map algebra. The paper describes an implementation of the level set methods in a map algebra programming language, called MapScript, and gives example program scripts for applications in ecology and hydrology.

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Rathjens, H., and N. Oppelt. "SWAT model calibration of a grid-based setup." Advances in Geosciences 32 (December 11, 2012): 55–61. http://dx.doi.org/10.5194/adgeo-32-55-2012.

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Abstract. The eco-hydrological model SWAT (Soil and Water Assessment Tool) is a useful tool to simulate the effects of catchment processes and water management practices on the water cycle. For each catchment some model parameters (e.g. ground water delay time, ground water level) remain constant and therefore are used as constant values; other parameters such as soil types or land use are spatially variable and thus have to be spatially discretized. SWAT setup interfaces process input data to fit the data format requirements and to discretize the spatial characteristics of the catchment area. The primarily used configuration is the sub-watershed discretization scheme. This spatial setup method, however, results in a loss of spatial information which can be problematic for SWAT applications that require a spatially detailed description of the catchment area. At present no SWAT interface is available which provides the management of input and output data based on grid cells. To fill this gap, the authors developed a grid-based model interface. To perform hydrological studies, the SWAT user first calibrates the model to fit to the environmental and hydrological conditions of the catchment. Compared to the sub-watershed approach, the grid-based setup significantly increases model computation time and hence aggravates calibration according to established calibration guidelines. This paper describes how a conventional set of sub-watershed SWAT parameters can be used to calibrate the corresponding grid-based model. The procedure was evaluated in a sub-catchment of the River Elbe (Northern Germany). The simulation of daily discharge resulted in Nash-Sutcliffe efficiencies ranging from 0.76 to 0.78 and from 0.61 to 0.65 for the calibration and validation period respectively; thus model performance is satisfactory. The sub-watershed and grid configuration simulate comparable discharges at the catchment outlet (R2 = 0.99). Nevertheless, the major advantage of the grid-based set-up is an enhanced spatial description of landscape units inducing a more realistic spatial distribution of model output parameters.

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Fayolle, Patrice, and Dara W. Childs. "Rotordynamic Evaluation of a Roughened-Land Hybrid Bearing." Journal of Tribology 121, no. 1 (January 1, 1999): 133–38. http://dx.doi.org/10.1115/1.2833794.

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Hybrid bearings represent an attractive alternative to ball bearings for use in highspeed cryogenic turbopumps. However, the internally-developed cross-coupled forces can generate instabilities responsible for a speed limitation of the machine. To reduce these forces and raise the onset speed of instability, the use of deliberately-roughened stators, already successfully tested for liquid “damper” seals, is investigated. Rotor-dynamic results are presented for a five-pocket orifice-compensated hole-pattern-land hybrid bearing tested with water at high speed and high pressure. Experimental data show a good prediction of leakage flow rate and direct damping but a significant improvement in stability compared to a conventional smooth-land hybrid bearing, resulting in an elevation of the onset speed of instability. Comparisons between measurements and predictions from a code developed by San Andres (1994) shows good predictions for flowrate and direct damping but an over prediction for the direct and cross-coupled stiffness coefficients by about 30 and 50 percent, respectively. The use of the Moody friction-factor model is thought to be mainly responsible for the poorer predictions of stiffness coefficients.

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Sánchez-García, Elena, Ángel Balaguer-Beser, Jaime Almonacid-Caballer, and Josep Eliseu Pardo-Pascual. "A New Adaptive Image Interpolation Method to Define the Shoreline at Sub-Pixel Level." Remote Sensing 11, no. 16 (August 12, 2019): 1880. http://dx.doi.org/10.3390/rs11161880.

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This paper presents a new methodological process for detecting the instantaneous land-water border at sub-pixel level from mid-resolution satellite images (30 m/pixel) that are freely available worldwide. The new method is based on using an iterative procedure to compute Laplacian roots of a polynomial surface that represents the radiometric response of a set of pixels. The method uses a first approximation of the shoreline at pixel level (initial pixels) and selects a set of neighbouring pixels to be part of the analysis window. This adaptive window collects those stencils in which the maximum radiometric variations are found by using the information given by divided differences. Therefore, the land-water surface is computed by a piecewise interpolating polynomial that models the strong radiometric changes between both interfaces. The assessment is tested on two coastal areas to analyse how their inherent differences may affect the method. A total of 17 Landsat 7 and 8 images (L7 and L8) were used to extract the shorelines and compare them against other highly accurate lines that act as references. Accurate quantitative coastal data from the satellite images is obtained with a mean horizontal error of 4.38 ± 5.66 m and 1.79 ± 2.78 m, respectively, for L7 and L8. Prior methodologies to reach the sub-pixel shoreline are analysed and the results verify the solvency of the one proposed.

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Pan, Tong, Xiao Jing Li, Hao Peng Wang, and Kai Zhao. "Research on LAI Retrieving Applied for Virtual Reality Simulation of Vegetation." Applied Mechanics and Materials 263-266 (December 2012): 1473–77. http://dx.doi.org/10.4028/www.scientific.net/amm.263-266.1473.

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It is the key process for developing usability of virtual reality simulation of vegetation taking into account soil, chemistry elements of water, temperature and humidity of land surface, and lighting. Retrieving the characteristics of vegetation from remote sensing data effectively and exactly, building the relationship between remote sensing data and interfaces of VR-vegetation models are important. The paper discusses dense vegetation model, nondense vegetation model, and two-stream approximation model applied for LAI retrieving, analyzes the efficiency of the methods; presents the process and method of LAI retrieving based on FPAR. The research offers the key methods and theoretic support for virtual reality simulation of vegetation based on spatial remote sensing information. The research is the primary work of digital agriculture, and important for monitoring corn growth and estimating in northeast of China.

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Fujita, S., P. Holmlund, K. Matsuoka, H. Enomoto, K. Fukui, F. Nakazawa, S. Sugiyama, and S. Surdyk. "Radar diagnosis of the subglacial conditions in Dronning Maud Land, East Antarctica." Cryosphere Discussions 6, no. 3 (May 24, 2012): 1781–837. http://dx.doi.org/10.5194/tcd-6-1781-2012.

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Abstract. In order to better understand the spatial distribution of subglacial environments, ground-based radar sounding data for a total distance of ~3300 km across Dronning Maud Land, East Antarctica, were analyzed. The relationship between geometrically corrected bed returned power [Pcbed]dB in decibels and ice thickness H was examined. When H is smaller, [Pcbed]dB was found to decrease simply with increasing H, which is explicable by the thickness variation of dielectric attenuation. However, an anomalous increase in [Pcbed]dB at larger H occurred, which was independent of the choice of radar frequencies or radar-pulse widths. We suggest that the existence of water at the ice/substrate interfaces at larger H caused this anomalous increase. We herein propose a new analytical method using these features to delineate frozen and temperate bed areas. Approximately two-thirds of the investigated area was found to have a temperate bed. Basal melting tends to occur when H is larger and the surface elevation is lower. In other words, beds inland of the ice sheet tend to be temperate, with the exception of subglacial high mountains. In contrast, beds of coastal areas tend to be frozen, with the exception of fast-flowing ice at subglacial lowland or troughs. These observations suggest that subglacial water is dominantly produced at the bed of wide inland plateau and that the water is discharged to the sea dominantly through a bed of fast-flowing ice. We also found that a 20-km-wide bed in the subglacial high mountains of an inland plateau near Dome Fuji is frozen, suggesting the existence of very old ice above the bed.

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Brewer, Matthew C., and Clifford F. Mass. "Projected Changes in Heat Extremes and Associated Synoptic- and Mesoscale Conditions over the Northwest United States." Journal of Climate 29, no. 17 (August 22, 2016): 6383–400. http://dx.doi.org/10.1175/jcli-d-15-0641.1.

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Abstract A number of studies have suggested that heat waves will increase in frequency, intensity, and duration under anthropogenic global warming. However, changes to heat extremes and temperature distributions in general are less understood in regions of complex terrain and substantial land–water contrasts. Such surface variations are important in the northwest United States, where synoptic- and mesoscale circulations interact with local topography and land–water interfaces to produce heat waves that have substantial impacts on fire weather, air quality, wind energy, and the population in general. Thus it is crucial to identify how the synoptic- and mesoscale circulations that drive such local extremes will change in a warming world. This paper analyzes changes to the conditions associated with heat extremes over the northwest United States by utilizing global and regional climate models. A maximum in 700-hPa warming is projected over the northwest United States and southwest Canada, with low-level warming attenuated near the coast. Soil moisture declines are projected over the region, which further enhances future extremes. It is found that low-level zonal wind distributions over the northwest United States become narrower, leading to fewer days with strong offshore flow. This is important since extreme warming events are associated with the strongest offshore/downslope flow. Historical and future regional temperature distributions are described and it is shown that although CMIP5 models predict increases in heat extremes for west Oregon and Washington, these increases are less than for inland areas.

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Trimmel, Heidelinde, Philipp Weihs, David Leidinger, Herbert Formayer, Gerda Kalny, and Andreas Melcher. "Can riparian vegetation shade mitigate the expected rise in stream temperatures due to climate change during heat waves in a human-impacted pre-alpine river?" Hydrology and Earth System Sciences 22, no. 1 (January 18, 2018): 437–61. http://dx.doi.org/10.5194/hess-22-437-2018.

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Abstract. Global warming has already affected European rivers and their aquatic biota, and climate models predict an increase of temperature in central Europe over all seasons. We simulated the influence of expected changes in heat wave intensity during the 21st century on water temperatures of a heavily impacted pre-alpine Austrian river and analysed future mitigating effects of riparian vegetation shade on radiant and turbulent energy fluxes using the deterministic Heat Source model. Modelled stream water temperature increased less than 1.5 ∘C within the first half of the century. Until 2100, a more significant increase of around 3 ∘C in minimum, maximum and mean stream temperatures was predicted for a 20-year return period heat event. The result showed clearly that in a highly altered river system riparian vegetation was not able to fully mitigate the predicted temperature rise caused by climate change but would be able to reduce water temperature by 1 to 2 ∘C. The removal of riparian vegetation amplified stream temperature increases. Maximum stream temperatures could increase by more than 4 ∘C even in annual heat events. Such a dramatic water temperature shift of some degrees, especially in summer, would indicate a total shift of aquatic biodiversity. The results demonstrate that effective river restoration and mitigation require re-establishing riparian vegetation and emphasize the importance of land–water interfaces and their ecological functioning in aquatic environments.

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Rumiano, Florent, Elodie Wielgus, Eve Miguel, Simon Chamaillé-Jammes, Hugo Valls-Fox, Daniel Cornélis, Michel De Garine-Wichatitsky, Hervé Fritz, Alexandre Caron, and Annelise Tran. "Remote Sensing of Environmental Drivers Influencing the Movement Ecology of Sympatric Wild and Domestic Ungulates in Semi-Arid Savannas, a Review." Remote Sensing 12, no. 19 (October 2, 2020): 3218. http://dx.doi.org/10.3390/rs12193218.

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Interfaces between protected areas and their peripheries in southern Africa are subject to interactions between wildlife and livestock that vary in frequency and intensity. In these areas, the juxtaposition between production and conservation land uses in a context of increasing anthropisation can create issues associated with human-wildlife coexistence and raises concerns for biodiversity conservation, local development and livelihoods. This literature review aimed at addressing the need to consolidate and gather in one article current knowledge on potential uses of satellite remote sensing (SRS) products by movement ecologists to investigate the sympatry of wildlife/domestic ungulates in savanna interface environments. A keyword querying process of peer reviewed scientific paper, thesis and books has been implemented to identify references that (1) characterize the main environmental drivers impacting buffalo (Syncerus caffer caffer) and cattle (Bos taurus & Bos indicus) movements in southern Africa environments, (2) describe the SRS contribution to discriminate and characterize these drivers. In total, 327 references have been selected and analyzed. Surface water, precipitation, landcover and fire emerged as key drivers impacting the buffalo and cattle movements. These environmental drivers can be efficiently characterized by SRS, mainly through open-access SRS products and standard image processing methods. Applying SRS to better understand buffalo and cattle movements in semi-arid environments provides an operational framework that could be replicated in other type of interface where different wild and domestic species interact. There is, however, a need for animal movement ecologists to reinforce their knowledge of remote sensing and/or to increase pluridisciplinary collaborations.

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Layek, Mrinal Kanti, Palash Debnath, Probal Sengupta, and Abhijit Mukherjee. "Delineation of Sedimentary Facies and Groundwater-Sea Water Disposition in an Intertidal Zone of the Bay of Bengal using GPR and VES." Journal of Environmental and Engineering Geophysics 23, no. 2 (June 2018): 235–49. http://dx.doi.org/10.2113/jeeg23.2.235.

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A combination of geophysical study including ground penetrating radar (GPR) and vertical electrical sounding (VES) was done to identify different shallow-subsurface depositional features in an intertidal coast of the eastern parts of India, adjoining the Bay of Bengal (BoB) (Chandipur, Odisha state). The study was aimed to understand the variation of sedimentary depositional sequences, prograding to the ocean from land, as well as towards the confluence of a river channel with the BoB. Six VES points and 85 GPR traverses were taken in the intertidal flat. The data were calibrated with sedimentary sequences retrieved from simultaneously drilled boreholes in four locations. Resistivity data clearly demonstrate the subsurface sediment layer boundaries with water saturation variability, up to 156 m below ground surface (bgs). The data suggest thickening of brackish water saturated clay layers towards the southwestern part. GPR data were capable of resolving the geometry of intertidal dunes, buried palaeo-channels, erosional surface, water table, eolian deposit of sand, and washover delta depositional features which are all present in this study area. Several erosional surfaces, related to sedimentary processes, e.g., delta overwash processes, were clearly demarcated. The study also successfully identified and visualized the saline-fresh groundwater interfaces and submarine ground water discharge (SGD) zones. Consequently, based on these data, a conceptual model of the depositional and erosional history of the sedimentation of the area, as well as the coastal hydrogeological disposition, was conceived.

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McNicol, Gavin, Zhongjie Yu, Z. Carter Berry, Nathan Emery, Fiona M. Soper, and Wendy H. Yang. "Tracing plant–environment interactions from organismal to planetary scales using stable isotopes: a mini review." Emerging Topics in Life Sciences 5, no. 2 (February 26, 2021): 301–16. http://dx.doi.org/10.1042/etls20200277.

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Natural isotope variation forms a mosaic of isotopically distinct pools across the biosphere and flows between pools integrate plant ecology with global biogeochemical cycling. Carbon, nitrogen, and water isotopic ratios (among others) can be measured in plant tissues, at root and foliar interfaces, and in adjacent atmospheric, water, and soil environments. Natural abundance isotopes provide ecological insight to complement and enhance biogeochemical research, such as understanding the physiological conditions during photosynthetic assimilation (e.g. water stress) or the contribution of unusual plant water or nutrient sources (e.g. fog, foliar deposition). While foundational concepts and methods have endured through four decades of research, technological improvements that enable measurement at fine spatiotemporal scales, of multiple isotopes, and of isotopomers, are advancing the field of stable isotope ecology. For example, isotope studies now benefit from the maturation of field-portable infrared spectroscopy, which allows the exploration of plant–environment sensitivity at physiological timescales. Isotope ecology is also benefiting from, and contributing to, new understanding of the plant–soil–atmosphere system, such as improving the representation of soil carbon pools and turnover in land surface models. At larger Earth-system scales, a maturing global coverage of isotope data and new data from site networks offer exciting synthesis opportunities to merge the insights of single-or multi-isotope analysis with ecosystem and remote sensing data in a data-driven modeling framework, to create geospatial isotope products essential for studies of global environmental change.

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35

Lama, Furbe, Sudeep Thakuri, Narayan Prasad Ghimire, and Rabin Malla. "Ecotone vegetation and water quality of Rara and Begnas Lakes, Nepal." Himalayan Biodiversity 6 (December 2, 2018): 27–37. http://dx.doi.org/10.3126/hebids.v6i0.33529.

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Land-water interfaces of lakes are highly dynamic and are responsible for the stability and maintenance of ecosystems. This study was carried out to understand the ecotone vegetation and the physico-chemical characteristics of waters of Begnas and Rara lakes of Nepal. For vegetation survey, line transects (perpendicular bi-sector to lake boundary), were used along the lake boundaries at an interval of 500 m; three quadrats of 1 m x 1 m size were laid on each line transect (off shore, boundary line, and on shore). All vegetation species in the sample quadrates were recorded. For probing water quality, lakes were divided into three blocks, then sampling was conducted on a consecutive day. Physico-chemical parameters —temperature, pH, electric conductivity (EC), dissolved oxygen (DO), total dissolved solid (TDS), ammonia, and nitrate—were measured. A total of 55 species under 38 families and 28 orders were recorded from ecotone of Begnas lake. In Rara lake, 56 species of 41 families and 22 orders were recorded. Poaceae was the dominant largest family in Begnas which was followed by Asteraceae. In Rara lake, Rosaceae was the dominant family which was followed by Pinaceae. Temperature, pH, and DO values decreased with depth, but EC and TDS e increased with depth, in both Begnas and Rara lakes. Ammonia and Nitrate were below the detectable limit of the instrument, indicating low nutrient contents of both lakes. The study established the baseline information about the diversity of ecotone vegetation; both the lakes show clear changes in physiochemical parameters with lake depths.

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Bedoya-Soto, Juan, Germán Poveda, and David Sauchyn. "New Insights on Land Surface-Atmosphere Feedbacks over Tropical South America at Interannual Timescales." Water 10, no. 8 (August 17, 2018): 1095. http://dx.doi.org/10.3390/w10081095.

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We present a simplified overview of land-atmosphere feedbacks at interannual timescales over tropical South America as structural sets of linkages among surface air temperature (T), specific humidity at 925 hPa (q925), volumetric soil water content (Θ), precipitation (P), and evaporation (E), at monthly scale during 1979–2010. Applying a Maximum Covariance Analysis (MCA), we identify the modes of greatest interannual covariability in the datasets. Time series extracted from the MCAs were used to quantify linear and non-linear metrics at up to six-month lags to establish connections among variables. All sets of metrics were summarized as graphs (Graph Theory) grouped according to their highest ENSO-degree association. The core of ENSO-activated interactions is located in the Amazon River basin and in the Magdalena-Cauca River basin in Colombia. Within the identified multivariate structure, Θ enhances the interannual connectivity since it often exhibits two-way feedbacks with the whole set of variables. That is, Θ is a key variable in defining the spatiotemporal patterns of P and E at interannual time-scales. For both the simultaneous and lagged analysis, T activates non-linear associations with q925 and Θ. Under the ENSO influence, T is a key variable to diagnose the dynamics of interannual feedbacks of the lower troposphere and soil interfaces over tropical South America. ENSO increases the interannual connectivity and memory of the feedback mechanisms.

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Marvez, Eduardo, Debra Houry, Steven Weiss, Juliette Saussy, and Dawne Orgeron. "A land-water interface collision." Prehospital Emergency Care 3, no. 3 (January 1999): 260–62. http://dx.doi.org/10.1080/10903129908958948.

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Downing, John P., Michel Meybeck, James C. Orr, R. R. Twilley, and H. W. Scharpenseel. "Land and water interface zones." Water, Air, & Soil Pollution 70, no. 1-4 (October 1993): 123–37. http://dx.doi.org/10.1007/bf01104992.

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39

Andrés, Luis San, Thomas Soulas, and Patrice Fayolle. "A Bulk-Flow Model of Angled Injection Lomakin Bearings." Journal of Engineering for Gas Turbines and Power 129, no. 1 (March 1, 2002): 195–204. http://dx.doi.org/10.1115/1.2227032.

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This paper introduces a bulk-flow model for prediction of the static and dynamic force coefficients of angled injection Lomakin bearings. The analysis accounts for the flow interaction between the injection orifices, the supply circumferential groove, and the thin film lands. A one control-volume model in the groove is coupled to a bulk-flow model within the film lands of the bearing. Bernoulli-type relationships provide closure at the flow interfaces. Flow turbulence is accounted for with shear stress parameters and Moody’s friction factors. The flow equations are solved numerically using a robust computational method. Comparisons between predictions and experimental results for a tangential-against-rotation injection water Lomakin bearing show that novel model well predicts the leakage and direct stiffness and damping coefficients. Computed cross-coupled stiffness coefficients follow the experimental trends for increasing rotor speeds and supply pressures, but quantitative agreement remains poor. A parameter investigation shows evidence of the effects of the groove and land geometries on the Lomakin bearing flowrate and force coefficients. The orifice injection angle does not influence the bearing static performance, although it largely affects its stability characteristics through the evolution of the cross-coupled stiffnesses. The predictions confirm the promising stabilizing effect of the tangential-against-rotation injection configuration. Two design parameters, comprised of the feed orifices area and groove geometry, define the static and dynamic performance of Lomakin bearing. The analysis also shows that the film land clearance and length have a larger impact on the Lomakin bearing rotordynamic behavior than its groove depth and length.

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Oliver, Y. M., E. C. Lefroy, R. Stirzaker, and C. L. Davies. "Deep-drainage control and yield: the trade-off between trees and crops in agroforestry systems in the medium to low rainfall areas of Australia." Australian Journal of Agricultural Research 56, no. 10 (2005): 1011. http://dx.doi.org/10.1071/ar04213.

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In the dryland cropping areas of southern Australia, at risk from dryland salinity, tree belts can improve water management by taking up water unused by crops, with the risk that crop yield will be reduced through competition. As there are few direct markets for tree products grown in the medium to low rainfall areas, the design of agroforestry systems becomes important in reducing the trade-off in crop yield. This study examined some factors that influence the trade-off between crop yield and deep-drainage control in order to develop design guidelines for medium to low rainfall agroforestry. Twenty-one sites in the grain-growing region of Western Australia and southern New South Wales were surveyed over 2 years for crop yields, tree leaf area index, and estimated recharge, providing data from 32 tree–crop interfaces on the relative influence of environmental factors and farming system characteristics on the trade-off between water management and crop yield. The factors most strongly correlated with higher yields were water-gaining sites, orientation that provided shelter from southerly to north-westerly (S, SW, W, NW) winds, and tree age (<10 years). The factors most strongly correlated with the area of cropped land protected against deep drainage were tree age (>10 years), lighter soil types, and low rainfall (<400 mm). Economic analysis of the trade-off required to produce a particular deep-drainage reduction target produced 3 groups of sites: (1) those where trees resulted in a gross margin increase of $15/ha and an estimated deep-drainage reduction of 52% (n = 3), (2) those with a gross margin loss of $49/ha and estimated deep-drainage reduction of 47% (n = 11), and (3) those with a gross margin loss of $163/ha and a deep-drainage reduction of 37% (n = 18). None of the 3 sites in the first group were in the most favourable class in both years, highlighting the vulnerability of a relatively fixed farming system to climate variability.

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van Griensven, A., P. Ndomba, S. Yalew, and F. Kilonzo. "Critical review of the application of SWAT in the upper Nile Basin countries." Hydrology and Earth System Sciences Discussions 9, no. 3 (March 20, 2012): 3761–88. http://dx.doi.org/10.5194/hessd-9-3761-2012.

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Abstract. The Soil and Water Assessment Tool (SWAT) is a hydrological simulation tool that is widely applied within the Nile basin. Up to date, more than 20 peer reviewed papers describe the use of SWAT for a variety of problems in the upper Nile basin countries, such as erosion modeling, land use modeling, climate change impact modeling and water resources management. The majority of the studies are clustered in the tropical highlands in Ethiopia and around Lake Victoria. The popularity of SWAT is attributed to the fact that the tool is freely available and that it is readily applicable through the development of Geographic Information System (GIS) based interfaces and its easy linkage to sensitivity, calibration and uncertainty analysis tools. The online and free availability of basic GIS data that are required for SWAT made its applicability more straight forward even in data scarce areas. However, the easy use of SWAT may not always lead to knowledgeable models. In this paper, we aim at critically reviewing the use of SWAT in the context of the modeling purpose and problem descriptions in the tropical highlands of the Nile Basin countries. A number of criteria are used to evaluate the model set-up, model performances, physical representation of the model parameters, and the correctness of the hydrological model balance. On the basis of performance indicators, the majority of the SWAT models were classified as giving satisfactory to very good results. Nevertheless, the hydrological mass balances as reported in several papers contained losses that might not be justified. Several papers also reported unrealistic parameter values. More worrying is that many papers lack this information. For this reason, it is difficult to give an overall positive evaluation to most of the reported SWAT models. An important gap is the lack of attention that is given to the vegetation and crop processes. None of the papers reported any adaptation to the crop parameters, or any crop related output such as leaf area index, biomass or crop yields. A proper simulation of the land cover is important for obtaining correct runoff generation, evapotranspiration and erosion computations. It is also found that a comparison of SWAT applications on the same or similar case study but by different research teams and/or model versions resulted in very different results. It is therefore recommended to try to find better methods to evaluate the representativeness of the distributed processes and parameters, especially when land use studies are envisaged or predictions of the future through environmental changes. The main recommendation is that more details on the model set-up, the parameters and outputs should be provided in the journal papers or supplementary materials in order to allow for a more stringent evaluation of these models.

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Parnell, John, and Sean McMahon. "Physical and chemical controls on habitats for life in the deep subsurface beneath continents and ice." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 374, no. 2059 (January 28, 2016): 20140293. http://dx.doi.org/10.1098/rsta.2014.0293.

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The distribution of life in the continental subsurface is likely controlled by a range of physical and chemical factors. The fundamental requirements are for space to live, carbon for biomass and energy for metabolic activity. These are inter-related, such that adequate permeability is required to maintain a supply of nutrients, and facies interfaces invite colonization by juxtaposing porous habitats with nutrient-rich mudrocks. Viable communities extend to several kilometres depth, diminishing downwards with decreasing porosity. Carbon is contributed by recycling of organic matter originally fixed by photosynthesis, and chemoautotrophy using crustal carbon dioxide and methane. In the shallow crust, the recycled component predominates, as processed kerogen or hydrocarbons, but abiotic carbon sources may be significant in deeper, metamorphosed crust. Hydrogen to fuel chemosynthesis is available from radiolysis, mechanical deformation and mineral alteration. Activity in the subcontinental deep biosphere can be traced through the geological record back to the Precambrian. Before the colonization of the Earth's surface by land plants, a geologically recent event, subsurface life probably dominated the planet's biomass. In regions of thick ice sheets the base of the ice sheet, where liquid water is stable and a sediment layer is created by glacial erosion, can be regarded as a deep biosphere habitat. This environment may be rich in dissolved organic carbon and nutrients accumulated from dissolving ice, and from weathering of the bedrock and the sediment layer.

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Indumati, S., R. B. Oza, Y. S. Mayya, V. D. Puranik, and H. S. Kushwaha. "Dispersion of pollutants over land–water–land interface: Study using CALPUFF model." Atmospheric Environment 43, no. 2 (January 2009): 473–78. http://dx.doi.org/10.1016/j.atmosenv.2008.09.030.

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44

van Griensven, A., P. Ndomba, S. Yalew, and F. Kilonzo. "Critical review of SWAT applications in the upper Nile basin countries." Hydrology and Earth System Sciences 16, no. 9 (September 20, 2012): 3371–81. http://dx.doi.org/10.5194/hess-16-3371-2012.

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Abstract. The Soil and Water Assessment Tool (SWAT) is an integrated river basin model that is widely applied within the Nile basin. Up to date, more than 20 peer-reviewed papers describe the use of SWAT for a variety of problems in the upper Nile basin countries, such as erosion modelling, land use and climate change impact modelling and water resources management. The majority of the studies are focused on locations in the tropical highlands in Ethiopia and around Lake Victoria. The popularity of SWAT is attributed to the fact that the tool is freely available and that it is readily applicable through the development of geographic information system (GIS) based interfaces and its easy linkage to sensitivity, calibration and uncertainty analysis tools. The online and free availability of basic GIS data that are required for SWAT made its applicability more straightforward even in data-scarce areas. However, the easy use of SWAT may not always lead to appropriate models which is also a consequence of the quality of the available free databases in these regions. In this paper, we aim at critically reviewing the use of SWAT in the context of the modelling purpose and problem descriptions in the tropical highlands of the Nile basin countries. To evaluate the models that are described in journal papers, a number of criteria are used to evaluate the model set-up, model performances, physical representation of the model parameters, and the correctness of the hydrological model balance. On the basis of performance indicators, the majority of the SWAT models were classified as giving satisfactory to very good results. Nevertheless, the hydrological mass balances as reported in several papers contained losses that might not be justified. Several papers also reported the use of unrealistic parameter values. More worrying is that many papers lack this information. For this reason, most of the reported SWAT models have to be evaluated critically. An important gap is the lack of attention that is given to the vegetation and crop processes. None of the papers reported any adaptation to the crop parameters, or any crop-related output such as leaf area index, biomass or crop yields. A proper simulation of the land cover is important for obtaining correct runoff generation, evapotranspiration and erosion computations. It is also found that a comparison of SWAT applications on the same or similar case study but by different research teams and/or model versions resulted in very different results. It is therefore recommended to find better methods to evaluate the representativeness of the distributed processes and parameters (especially when land use studies are envisaged) or predictions of the future through environmental changes. The main recommendation is that more details on the model set-up, the parameters and outputs should be provided in the journal papers or supplementary materials in order to allow for a more stringent evaluation of these models.

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Le Roy, Emilie, Virginie Sanial, Matthew A. Charette, Pieter van Beek, François Lacan, Stéphanie H. M. Jacquet, Paul B. Henderson, et al. "The <sup>226</sup>Ra–Ba relationship in the North Atlantic during GEOTRACES-GA01." Biogeosciences 15, no. 9 (May 17, 2018): 3027–48. http://dx.doi.org/10.5194/bg-15-3027-2018.

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Abstract. We report detailed sections of radium-226 (226Ra, T1∕2 = 1602 years) activities and barium (Ba) concentrations determined in the North Atlantic (Portugal–Greenland–Canada) in the framework of the international GEOTRACES program (GA01 section – GEOVIDE project, May–July 2014). Dissolved 226Ra and Ba are strongly correlated along the section, a pattern that may reflect their similar chemical behavior. Because 226Ra and Ba have been widely used as tracers of water masses and ocean mixing, we investigated their behavior more thoroughly in this crucial region for thermohaline circulation, taking advantage of the contrasting biogeochemical patterns existing along the GA01 section. We used an optimum multiparameter (OMP) analysis to distinguish the relative importance of physical transport (water mass mixing) from nonconservative processes (sedimentary, river or hydrothermal inputs, uptake by particles and dissolved–particulate dynamics) on the 226Ra and Ba distributions in the North Atlantic. Results show that the measured 226Ra and Ba concentrations can be explained by conservative mixing for 58 and 65 % of the samples, respectively, notably at intermediate depth, away from the ocean interfaces. 226Ra and Ba can thus be considered conservative tracers of water mass transport in the ocean interior on the space scales considered here, namely, on the order of a few thousand kilometers. However, regions in which 226Ra and Ba displayed nonconservative behavior and in some cases decoupled behaviors were also identified, mostly at the ocean boundaries (seafloor, continental margins and surface waters). Elevated 226Ra and Ba concentrations found in deepwater in the West European Basin suggest that lower Northeast Atlantic Deep Water (NEADWl) accumulates 226Ra and Ba from sediment diffusion and/or particle dissolution during transport. In the upper 1500 m of the West European Basin, deficiencies in 226Ra and Ba are likely explained by their incorporation in planktonic calcareous and siliceous shells, or in barite (BaSO4) by substitution or adsorption mechanisms. Finally, because Ba and 226Ra display different source terms (mostly deep-sea sediments for 226Ra and rivers for Ba), strong decoupling between 226Ra and Ba were observed at the land–ocean boundaries. This is especially true in the shallow stations near the coasts of Greenland and Newfoundland where high 226Ra ∕ Ba ratios at depth reflect the diffusion of 226Ra from sediment and low 226Ra ∕ Ba ratios in the upper water column reflect the input of Ba associated with meteoric waters.

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Pringle, Catherine M., and Mary Barber. "The Land–Water Interface: Science for a Sustainable Biosphere1." Ecological Applications 10, no. 4 (August 2000): 939–40. http://dx.doi.org/10.1890/1051-0761(2000)010[0939:tlwisf]2.0.co;2.

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Drees, L., J. Kusche, and R. Roscher. "MULTI-MODAL DEEP LEARNING WITH SENTINEL-3 OBSERVATIONS FOR THE DETECTION OF OCEANIC INTERNAL WAVES." ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences V-2-2020 (August 3, 2020): 813–20. http://dx.doi.org/10.5194/isprs-annals-v-2-2020-813-2020.

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Abstract. The observation of waves that propagate along density interfaces inside the ocean poses a significant challenge, as their visible surface signatures are much lower compared to their internal amplitudes. However, monitoring internal waves is important as they redistribute large amounts of energy, play a role in mixing and vertical heat transfer, and modify water and nutrient transports. Although satellite observations would allow global monitoring of internal waves at constant time intervals, their automatic detection is challenging: In optical images, internal waves are hardly visible and can be obscured by clouds, whereas radar data have limitations in coastal regions and their spatial coverage is not perfect. Furthermore, the occurrence of internal waves can be confused with other ocean phenomena. In this work, we present an automated detection framework for internal waves based on multiple data sources in order to compensate for the shortcoming of single data sources. In our application, we use Ocean and Land Color Imager and Synthetic Aperture Radar Altimeter data. Our contributions are (1) we develop a multi-modal deep neural network SONet with multi-streams and late fusion, which performs a classification on the basis of training with both modalities, and (2) we establish a method to deal with missing modalities. Experiments in the Amazon Shelf region show SONet achieves adequate results when both modalities are available, but also when only a single modality is available. By exploiting correlations between the modalities, SONet classifies OLCI images off the SRAL ground track better than uni-modal network ONet, which describes a great advantage of our multi-modal network.

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Pe'eri, Shachak, Lynnette V. Morgan, William D. Philpot, and Andrew A. Armstrong. "Land-Water Interface Resolved from Airborne LIDAR Bathymetry (ALB) Waveforms." Journal of Coastal Research 62 (March 2011): 75–85. http://dx.doi.org/10.2112/si_62_8.

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Dominguez, Larry. "Beyond Biology: Can We Reconcile the Land–Water–Humankind Interface?" Fisheries 38, no. 2 (February 8, 2013): 84–86. http://dx.doi.org/10.1080/03632415.2013.760279.

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Akegbejo-Samsons, Yemi. "Climate change impacts on fisheries production in land-water interface." IOP Conference Series: Earth and Environmental Science 6, no. 29 (February 1, 2009): 292022. http://dx.doi.org/10.1088/1755-1307/6/29/292022.

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Journal articles on the topic 'Land-water interfaces'

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