Search results for: aquatic vegetation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1013

Search results for: aquatic vegetation

1013 Construction of Submerged Aquatic Vegetation Index through Global Sensitivity Analysis of Radiative Transfer Model

Authors: Guanhua Zhou, Zhongqi Ma

Abstract:

Submerged aquatic vegetation (SAV) in wetlands can absorb nitrogen and phosphorus effectively to prevent the eutrophication of water. It is feasible to monitor the distribution of SAV through remote sensing, but for the reason of weak vegetation signals affected by water body, traditional terrestrial vegetation indices are not applicable. This paper aims at constructing SAV index to enhance the vegetation signals and distinguish SAV from water body. The methodology is as follows: (1) select the bands sensitive to the vegetation parameters based on global sensitivity analysis of SAV canopy radiative transfer model; (2) take the soil line concept as reference, analyze the distribution of SAV and water reflectance simulated by SAV canopy model and semi-analytical water model in the two-dimensional space built by different sensitive bands; (3)select the band combinations which have better separation performance between SAV and water, and use them to build the SAVI indices in the form of normalized difference vegetation index(NDVI); (4)analyze the sensitivity of indices to the water and vegetation parameters, choose the one more sensitive to vegetation parameters. It is proved that index formed of the bands with central wavelengths in 705nm and 842nm has high sensitivity to chlorophyll content in leaves while it is less affected by water constituents. The model simulation shows a general negative, little correlation of SAV index with increasing water depth. Moreover, the index enhances capabilities in separating SAV from water compared to NDVI. The SAV index is expected to have potential in parameter inversion of wetland remote sensing.

Keywords: global sensitivity analysis, radiative transfer model, submerged aquatic vegetation, vegetation indices

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1012 Mapping Stress in Submerged Aquatic Vegetation Using Multispectral Imagery and Structure from Motion Photogrammetry

Authors: Amritha Nair, Fleur Visser, Ian Maddock, Jonas Schoelynck

Abstract:

Inland waters such as streams sustain a rich variety of species and are essentially hotspots for biodiversity. Submerged aquatic vegetation, also known as SAV, forms an important part of ecologically healthy river systems. Direct and indirect human influences, such as climate change are putting stress on aquatic plant communities, ranging from the invasion of non-native species and grazing, to changes in the river flow conditions and temperature. There is a need to monitor SAV, because they are in a state of deterioration and their disappearance will greatly impact river ecosystems. Like terrestrial plants, SAV can show visible signs of stress. However, the techniques used to map terrestrial vegetation from its spectral reflectance, are not easily transferable to a submerged environment. Optical remote sensing techniques are employed to detect the stress from remotely sensed images through multispectral imagery and Structure from Motion photogrammetry. The effect of the overlying water column in the form of refraction, attenuation of visible and near infrared bands in water, as well as highly moving targets, are NIR) key challenges that arise when remotely mapping SAV. This study looks into the possibility of mapping the changes in spectral signatures from SAV and their response to certain stresses.

Keywords: submerged aquatic vegetation, structure from motion, photogrammetry, multispectral, spectroscopy

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1011 Characterization of Fateh Sagar Wetland and Its Catchment Area at Udaipur City, (Raj.) India, Using High Resolution Data

Authors: Parul Bhalla, Sarvesh Palria

Abstract:

Wetlands are areas of land that are either temporarily or permanently covered by water. Wetlands exhibit enormous diversity according to their genesis, geographical location, water regime and chemistry, dominant plants and soil or sediment characteristics. The spatial and temporal characteristics of wetland in terms of turbidity and aquatic vegetation could serve as guiding tool, in conservation prioritization of wetlands. The aquatic vegetation in the wetland is an indicator of the trophic status of the wetland which has a bearing on the water quality, the turbidity level in any wetland is indicative of the quality of the water in it. To conserve and manage wetland resources, it is important to have inventory of wetland and its catchment. Fateh Sagar wetland in Udaipur city is the one of the important wetland for tourism industry and other economic activities in the region. Realizing the importance of the wetland, the present study has been taken up with the specific objective of delineation and characterization of Fateh Sagar wetland in terms of turbidity and aquatic vegetation, using high resolution satellite data such as Cartosat and LISS IV multi-temporal data, which will efficiently bring out the changes in water spread and quality parameters. The catchment of wetland has been also characterized for various features. The study leads in to takes necessary steps to conserve the wetland and its resources.

Keywords: aquatic vegetation, catchment, turbidity status, wetland

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1010 Variation of Manning’s Coefficient in a Meandering Channel with Emergent Vegetation Cover

Authors: Spandan Sahu, Amiya Kumar Pati, Kishanjit Kumar Khatua

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Vegetation plays a major role in deciding the flow parameters in an open channel. It enhances the aesthetic view of the revetments. The major types of vegetation in river typically comprises of herbs, grasses, weeds, trees, etc. The vegetation in an open channel usually consists of aquatic plants with complete submergence, partial submergence, floating plants. The presence of vegetative plants can have both benefits and problems. The major benefits of aquatic plants are they reduce the soil erosion, which provides the water with a free surface to move on without hindrance. The obvious problems are they retard the flow of water and reduce the hydraulic capacity of the channel. The degree to which the flow parameters are affected depends upon the density of the vegetation, degree of submergence, pattern of vegetation, vegetation species. Vegetation in open channel tends to provide resistance to flow, which in turn provides a background to study the varying trends in flow parameters having vegetative growth in the channel surface. In this paper, an experiment has been conducted on a meandering channel having sinuosity of 1.33 with rigid vegetation cover to investigate the effect on flow parameters, variation of manning’s n with degree of the denseness of vegetation, vegetation pattern and submergence criteria. The measurements have been carried out in four different cross-sections two on trough portion of the meanders, two on the crest portion. In this study, the analytical solution of Shiono and knight (SKM) for lateral distributions of depth-averaged velocity and bed shear stress have been taken into account. Dimensionless eddy viscosity and bed friction have been incorporated to modify the SKM to provide more accurate results. A mathematical model has been formulated to have a comparative analysis with the results obtained from Shiono-Knight Method.

Keywords: bed friction, depth averaged velocity, eddy viscosity, SKM

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1009 Roles of Aquatic Plants on Erosion Relief of Stream Bed

Authors: Jin-Hong Kim

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Roles of the vegetation to mitigate the erosion of the stream bed or to facilitate the deposition of the fine sediments by the species of the aquatic plants were presented. Field investigation on the estimation of the change of the bed level and the estimation of the flow characteristics were performed. The results showed that Phragmites japonica has the mitigation function of 0.3m-0.4m of the erosion in the range of higher than 1.0m/s of flow velocity at the vegetated region. Phragmites communis has the mitigation function of 0.2m-0.3m of the erosion in the range of higher than 0.7m/s of flow velocity at the vegetated region. Salix gracilistyla has greater role than Phragmites japonica and Phragmites communis to sustain the stable channel. It has the mitigation function of 0.4m-0.5m of the erosion in the range of higher than 1.4m/s of flow velocity. Miscanthus sacchariflorus has a weak role compared with that of Phragmites japonica and Salix gracilistyla, but it has still function for sustaining the stable bed. From these results, the vegetation has effective roles to mitigate the erosion or to facilitate the deposition of the stream bed.

Keywords: aquatic plants, Phragmites japonica, Phragmites communis, Salix gracilistyla

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1008 The Influence of the Soil in the Vegetation of the Luki Biosphere Reserve in the Democratic Republic of Congo

Authors: Sarah Okende

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It is universally recognized that the forests of the Congo Basin remain a common good and a complex ecosystem, and insufficiently known. Historically and throughout the world, forests have been valued for the multiple products and benefits they provide. In addition to their major role in the conservation of global biodiversity and in the fight against climate change, these forests also have an essential role in the regional and global ecology. This is particularly the case of the Luki Biosphere Reserve, a highly diversified evergreen Guinean-Congolese rainforest. Despite the efforts of sustainable management of the said reserve, the understanding of the place occupied by the soil under the influence of the latter does not seem to be an interesting subject for the general public or even scientists. The Luki biosphere reserve is located in the west of the DRC, more precisely in the south-east of Mayombe Congolais, in the province of Bas-Congo. The vegetation of the Luki Biosphere Reserve is very heterogeneous and diversified. It ranges from grassy formations to semi-evergreen dense humid forests, passing through edaphic formations on hydromorphic soils (aquatic and semi-aquatic vegetation; messicole and segetal vegetation; gascaricole vegetation; young secondary forests with Musanga cercropioides, Xylopia aethiopica, Corynanthe paniculata; mature secondary forests with Terminalia superba and Hymenostegia floribunda; primary forest with Prioria balsamifera; climax forests with Gilbertiodendron dewevrei, and Gilletiodendron kisantuense). Field observations and reading of previous and up-to-date work carried out in the Luki biosphere reserve are the methodological approaches for this study, the aim of which is to show the impact of soil types in determining the varieties of vegetation. The results obtained prove that the four different types of soil present (purplish red soils, developing on amphibolites; red soils, developed on gneisses; yellow soils occurring on gneisses and quartzites; and alluvial soils, developed on recent alluvium) have a major influence apart from other environmental factors on the determination of different facies of the vegetation of the Luki Biosphere Reserve. In conclusion, the Luki Biosphere Reserve is characterized by a wide variety of biotopes determined by the nature of the soil, the relief, the microclimates, the action of man, or the hydrography. Overall management (soil, biodiversity) in the Luki Biosphere Reserve is important for maintaining the ecological balance.

Keywords: soil, biodiversity, forest, Luki, rainforest

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1007 Effects of Soil Erosion on Vegetation Development

Authors: Josephine Wanja Nyatia

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The relationship between vegetation and soil erosion deserves attention due to its scientific importance and practical applications. A great deal of information is available about the mechanisms and benefits of vegetation in the control of soil erosion, but the effects of soil erosion on vegetation development and succession is poorly documented. Research shows that soil erosion is the most important driving force for the degradation of upland and mountain ecosystems. Soil erosion interferes with the process of plant community development and vegetation succession, commencing with seed formation and impacting throughout the whole growth phase and affecting seed availability, dispersal, germination and establishment, plant community structure and spatial distribution. There have been almost no studies on the effects of soil erosion on seed development and availability, of surface flows on seed movement and redistribution, and their influences on soil seed bank and on vegetation establishment and distribution. However, these effects may be the main cause of low vegetation cover in regions of high soil erosion activity, and these issues need to be investigated. Moreover, soil erosion is not only a negative influence on vegetation succession and restoration but also a driving force of plant adaptation and evolution. Consequently, we need to study the effects of soil erosion on ecological processes and on development and regulation of vegetation succession from the points of view of pedology and vegetation, plant and seed ecology, and to establish an integrated theory and technology for deriving practical solutions to soil erosion problems

Keywords: soil erosion, vegetation, development, seed availability

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1006 Avifaunal Diversity in the Mallathahalli Lake of Bangalore Urban District, Karnataka, India

Authors: Vidya Padmakumar, N. C. Tharavathy

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The study was conducted from July 2015 to July 2017 to determine and understand the occurrence, frequency and diversity of avifauna in the Mallathahalli Lake of Bangalore Urban district. During the study period, 46 species of both terrestrial, as well as, aquatic birds belonging to 30 families were identified out of which 9 families were aquatic birds and 21 families were terrestrial birds. There were 4 species of migratory birds out of 46, showing diurnal migration. There was a significant reduce in the number of bird species both terrestrial and aquatic during the summer season and also varied greatly during winters and monsoon. Of the total 24 species of aquatic birds, Fulica atra and Tachybaptus ruficolis were the most common with 100% frequency and the least frequent species with 3.02% frequency was identified as Threskiornis melanocephalus. Among the 22 species of terrestrial birds, Acridotheres tristis had a frequency of 89% and the least frequent was Pycnonotus cafer (4.45%). The most commonly encountered bird species were from the families- Anatidae, Podicipedidae, Ardeidae, Phalacrocoracidae, Rallidae, Accipitridae, Scolopacidae, Charadridae, Laridae, Meropidae, Hirudinidae. All the birds surviving around the area are dependent on the wetland and crop vegetation surrounding the lake, which are deteriorating due to anthropogenic interventions and urbanization which are rising to its peak gradually causing the decline in the avifaunal diversity.

Keywords: Avifaunal diversity, Mallathahalli lake, seasonal migration, urbanization

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1005 Greenland Monitoring Using Vegetation Index: A Case Study of Lal Suhanra National Park

Authors: Rabia Munsaf Khan, Eshrat Fatima

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The analysis of the spatial extent and temporal change of vegetation cover using remotely sensed data is of critical importance to agricultural sciences. Pakistan, being an agricultural country depends on this resource as it makes 70% of the GDP. The case study is of Lal Suhanra National Park, which is not only the biggest forest reserve of Pakistan but also of Asia. The study is performed using different temporal images of Landsat. Also, the results of Landsat are cross-checked by using Sentinel-2 imagery as it has both higher spectral and spatial resolution. Vegetation can easily be detected using NDVI which is a common and widely used index. It is an important vegetation index, widely applied in research on global environmental and climatic change. The images are then classified to observe the change occurred over 15 years. Vegetation cover maps of 2000 and 2016 are used to generate the map of vegetation change detection for the respective years and to find out the changing pattern of vegetation cover. Also, the NDVI values aided in the detection of percentage decrease in vegetation cover. The study reveals that vegetation cover of the area has decreased significantly during the year 2000 and 2016.

Keywords: Landsat, normalized difference vegetation index (NDVI), sentinel 2, Greenland monitoring

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1004 Biological Monitoring: Vegetation Cover, Bird Assemblages, Rodents, Terrestrial and Aquatic Invertebrates from a Closed Landfill

Authors: A. Cittadino, P. Gantes, C. Coviella, M. Casset, A. Sanchez Caro

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Three currently active landfills receive the waste from Buenos Aires city and the Great Buenos Aires suburbs. One of the first landfills to receive solid waste from this area was located in Villa Dominico, some 7 km south from Buenos Aires City. With an area of some 750 ha, including riparian habitats, divided into 14 cells, it received solid wastes from June 1979 through February 2004. In December 2010, a biological monitoring program was set up by CEAMSE and Universidad Nacional de Lujan, still operational to date. The aim of the monitoring program is to assess the state of several biological groups within the landfill and to follow their dynamics overtime in order to identify if any, early signs of damage the landfill activities might have over the biota present. Bird and rodent populations, aquatic and terrestrial invertebrates’ populations, cells vegetation coverage, and surrounding areas vegetation coverage and main composition are followed by quarterly samplings. Bird species richness and abundance were estimated by observation over walk transects on each environment. A total of 74 different species of birds were identified. Species richness and diversity were high for both riparian surrounding areas and within the landfill. Several grassland -typical of the 'Pampa'- bird species were found within the landfill, as well as some migratory and endangered bird species. Sherman and Tomahawk traps are set overnight for small mammal sampling. Rodent populations are just above detection limits, and the few specimens captured belong mainly to species common to rural areas, instead of city-dwelling species. The two marsupial species present in the region were captured on occasions. Aquatic macroinvertebrates were sampled on a watercourse upstream and downstream the outlet of the landfill’s wastewater treatment plant and are used to follow water quality using biological indices. Water quality ranged between weak and severe pollution; benthic invertebrates sampled before and after the landfill, show no significant differences in water quality using the IBMWP index. Insect biota from yellow sticky cards and pitfall traps showed over 90 different morphospecies, with Shannon diversity index running from 1.9 to 3.9, strongly affected by the season. An easy-to-perform non-expert demandant method was used to assess vegetation coverage. Two scales of determination are utilized: field observation (1 m resolution), and Google Earth images (that allow for a better than 5 m resolution). Over the eight year period of the study, vegetation coverage over the landfill cells run from a low 83% to 100% on different cells, with an average between 95 to 99% for the entire landfill depending on seasonality. Surrounding area vegetation showed almost 100% coverage during the entire period, with an average density from 2 to 6 species per sq meter and no signs of leachate damaged vegetation.

Keywords: biological indicators, biota monitoring, landfill species diversity, waste management

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1003 Mean Velocity Modeling of Open-Channel Flow with Submerged Vegetation

Authors: Mabrouka Morri, Amel Soualmia, Philippe Belleudy

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Vegetation affects the mean and turbulent flow structure. It may increase flood risks and sediment transport. Therefore, it is important to develop analytical approaches for the bed shear stress on vegetated bed, to predict resistance caused by vegetation. In the recent years, experimental and numerical models have both been developed to model the effects of submerged vegetation on open-channel flow. In this paper, different analytic models are compared and tested using the criteria of deviation, to explore their capacity for predicting the mean velocity and select the suitable one that will be applied in real case of rivers. The comparison between the measured data in vegetated flume and simulated mean velocities indicated, a good performance, in the case of rigid vegetation, whereas, Huthoff model shows the best agreement with a high coefficient of determination (R2=80%) and the smallest error in the prediction of the average velocities.

Keywords: analytic models, comparison, mean velocity, vegetation

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1002 Analyzing Impacts of Road Network on Vegetation Using Geographic Information System and Remote Sensing Techniques

Authors: Elizabeth Malebogo Mosepele

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Road transport has become increasingly common in the world; people rely on road networks for transportation purpose on a daily basis. However, environmental impact of roads on surrounding landscapes extends their potential effects even further. This study investigates the impact of road network on natural vegetation. The study will provide baseline knowledge regarding roadside vegetation and would be helpful in future for conservation of biodiversity along the road verges and improvements of road verges. The general hypothesis of this study is that the amount and condition of road side vegetation could be explained by road network conditions. Remote sensing techniques were used to analyze vegetation conditions. Landsat 8 OLI image was used to assess vegetation cover condition. NDVI image was generated and used as a base from which land cover classes were extracted, comprising four categories viz. healthy vegetation, degraded vegetation, bare surface, and water. The classification of the image was achieved using the supervised classification technique. Road networks were digitized from Google Earth. For observed data, transect based quadrats of 50*50 m were conducted next to road segments for vegetation assessment. Vegetation condition was related to road network, with the multinomial logistic regression confirming a significant relationship between vegetation condition and road network. The null hypothesis formulated was that 'there is no variation in vegetation condition as we move away from the road.' Analysis of vegetation condition revealed degraded vegetation within close proximity of a road segment and healthy vegetation as the distance increase away from the road. The Chi Squared value was compared with critical value of 3.84, at the significance level of 0.05 to determine the significance of relationship. Given that the Chi squared value was 395, 5004, the null hypothesis was therefore rejected; there is significant variation in vegetation the distance increases away from the road. The conclusion is that the road network plays an important role in the condition of vegetation.

Keywords: Chi squared, geographic information system, multinomial logistic regression, remote sensing, road side vegetation

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1001 Study of Eatable Aquatic Invertebrates in the River Dhansiri, Dimapur, Nagaland, India

Authors: Dilip Nath

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A study has been conducted on the available aquatic invertebrates in the river Dhansiri at Dimapur site. The study confirmed that the river body composed of aquatic macroinvertebrate community under two phyla viz., Arthropods and Molluscs. Total 10 species have been identified from there as the source of alternative protein food for the common people. Not only the protein source, they are also the component of aquatic food chain and indicators of aquatic ecosystem. Proper management and strategies to promote the edible invertebrates can be considered as the alternative protein and alternative income source for the common people for sustainable livelihood improvement.

Keywords: Dhansiri, Dimapur, invertebrates, livelihood improvement, protein

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1000 Monitoring and Management of Aquatic Macroinvertebrates for Determining the Level of Water Pollution Catchment Basin of Debed River, Armenia

Authors: Inga Badasyan

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Every year we do monitoring of water pollution of catchment basin of Debed River. Next, the Ministry of Nature Protection does modeling programme. Finely, we are managing the impact of water pollution in Debed river. Ecosystem technologies efficiency performance were estimated based on the physical, chemical, and macrobiological analyses of water on regular base between 2012 to 2015. Algae community composition was determined to assess the ecological status of Debed river, while vegetation was determined to assess biodiversity. Last time, experts werespeaking about global warming, which is having bad impact on the surface water, freshwater, etc. As, we know that global warming is caused by the current high levels of carbon dioxide in the water. Geochemical modelling is increasingly playing an important role in various areas of hydro sciences and earth sciences. Geochemical modelling of highly concentrated aqueous solutions represents an important topic in the study of many environments such as evaporation ponds, groundwater and soils in arid and semi-arid zones, costal aquifers, etc. The sampling time is important for benthic macroinvertebrates, for that reason we have chosen in the spring (abundant flow of the river, the beginning of the vegetation season) and autumn (the flow of river is scarce). The macroinvertebrates are good indicator for a chromic pollution and aquatic ecosystems. Results of our earlier investigations in the Debed river reservoirs clearly show that management problem of ecosystem reservoirs is topical. Research results can be applied to studies of monitoring water quality in the rivers and allow for rate changes and to predict possible future changes in the nature of the lake.

Keywords: ecohydrological monitoring, flood risk management, global warming, aquatic macroinvertebrates

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999 Remote Assessment and Change Detection of GreenLAI of Cotton Crop Using Different Vegetation Indices

Authors: Ganesh B. Shinde, Vijaya B. Musande

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Cotton crop identification based on the timely information has significant advantage to the different implications of food, economic and environment. Due to the significant advantages, the accurate detection of cotton crop regions using supervised learning procedure is challenging problem in remote sensing. Here, classifiers on the direct image are played a major role but the results are not much satisfactorily. In order to further improve the effectiveness, variety of vegetation indices are proposed in the literature. But, recently, the major challenge is to find the better vegetation indices for the cotton crop identification through the proposed methodology. Accordingly, fuzzy c-means clustering is combined with neural network algorithm, trained by Levenberg-Marquardt for cotton crop classification. To experiment the proposed method, five LISS-III satellite images was taken and the experimentation was done with six vegetation indices such as Simple Ratio, Normalized Difference Vegetation Index, Enhanced Vegetation Index, Green Atmospherically Resistant Vegetation Index, Wide-Dynamic Range Vegetation Index, Green Chlorophyll Index. Along with these indices, Green Leaf Area Index is also considered for investigation. From the research outcome, Green Atmospherically Resistant Vegetation Index outperformed with all other indices by reaching the average accuracy value of 95.21%.

Keywords: Fuzzy C-Means clustering (FCM), neural network, Levenberg-Marquardt (LM) algorithm, vegetation indices

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998 A Monitoring System to Detect Vegetation Growth along the Route of Power Overhead Lines

Authors: Eugene Eduful

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This paper introduces an approach that utilizes a Wireless Sensor Network (WSN) to detect vegetation encroachment between segments of distribution lines. The WSN was designed and implemented, involving the seamless integration of Arduino Uno and Mega systems. This integration demonstrates a method for addressing the challenges posed by vegetation interference. The primary aim of the study is to improve the reliability of power supply in areas characterized by forested terrain, specifically targeting overhead powerlines. The experimental results validate the effectiveness of the proposed system, revealing its ability to accurately identify and locate instances of vegetation encroachment with a remarkably high degree of precision.

Keywords: wireless sensor network, vegetation encroachment, line of sight, Arduino Uno, XBEE

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997 The Relationship between Ruins and Vegetation: Different Approaches during the Centuries and within the Various Disciplinary Fields, Investigation of Writings and Projects

Authors: Rossana Mancini

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The charm of a ruin colonised by wild plants and flowers is part of Western culture. The relationship between ruins and vegetation involves a wide range of different fields of research. During the first phase of the research the most important writings and projects about this argument were investigated, to understand how the perception of the co-existence of ruins and vegetation has changed over time and to investigate the various different approaches that these different fields have adopted when tackling this issue. The paper presents some practical examples of projects carried out from the early 1900s on. The major result is that specifically regards conservation, the best attitude is the management of change, an inevitable process when it comes to the co-existence of ruins and nature and, particularly, ruins and vegetation. Limiting ourselves to adopting measures designed to stop, or rather slow down, the increasing level of entropy (and therefore disorder) may not be enough.

Keywords: ruins, vegetation, conservation, archaeology, architecture

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996 Modeling Vegetation Phenological Characteristics of Terrestrial Ecosystems

Authors: Zongyao Sha

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Green vegetation plays a vital role in energy flows and matter cycles in terrestrial ecosystems, and vegetation phenology may not only be influenced by but also impose active feedback on climate changes. The phenological events of vegetation, such as the start of the season (SOS), end of the season (EOS), and length of the season (LOS), can respond to climate changes and affect gross primary productivity (GPP). Here we coupled satellite remote sensing imagery with FLUXNET observations to systematically map the shift of SOS, EOS, and LOS in global vegetated areas and explored their response to climate fluctuations and feedback on GPP during the last two decades. Results indicated that SOS advanced significantly, at an average rate of 0.19 days/year at a global scale, particularly in the northern hemisphere above the middle latitude (≥30°N) and that EOS was slightly delayed during the past two decades, resulting in prolonged LOS in 72.5% of the vegetated area. The climate factors, including seasonal temperature and precipitation, are attributed to the shifts in vegetation phenology but with a high spatial and temporal difference. The study revealed interactions between vegetation phenology and climate changes. Both temperature and precipitation affect vegetation phenology. Higher temperature as a direct consequence of global warming advanced vegetation green-up date. On the other hand, 75.9% and 20.2% of the vegetated area showed a positive correlation and significant positive correlation between annual GPP and length of vegetation growing season (LOS), likely indicating an enhancing effect on vegetation productivity and thus increased carbon uptake from the shifted vegetation phenology. Our study highlights a comprehensive view of the vegetation phenology changes of the global terrestrial ecosystems during the last two decades. The interactions between the shifted vegetation phenology and climate changes may provide useful information for better understanding the future trajectory of global climate changes. The feedback on GPP from the shifted vegetation phenology may serve as an adaptation mechanism for terrestrial ecosystems to mitigate global warming through improved carbon uptake from the atmosphere.

Keywords: vegetation phenology, growing season, NPP, correlation analysis

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995 Vegetation Index-Deduced Crop Coefficient of Wheat (Triticum aestivum) Using Remote Sensing: Case Study on Four Basins of Golestan Province, Iran

Authors: Hoda Zolfagharnejad, Behnam Kamkar, Omid Abdi

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Crop coefficient (Kc) is an important factor contributing to estimation of evapotranspiration, and is also used to determine the irrigation schedule. This study investigated and determined the monthly Kc of winter wheat (Triticum aestivum L.) using five vegetation indices (VIs): Normalized Difference Vegetation Index (NDVI), Difference Vegetation Index (DVI), Soil Adjusted Vegetation Index (SAVI), Infrared Percentage Vegetation Index (IPVI), and Ratio Vegetation Index (RVI) of four basins in Golestan province, Iran. 14 Landsat-8 images according to crop growth stage were used to estimate monthly Kc of wheat. VIs were calculated based on infrared and near infrared bands of Landsat 8 images using Geographical Information System (GIS) software. The best VIs were chosen after establishing a regression relationship among these VIs with FAO Kc and Kc that was modified for the study area by the previous research based on R² and Root Mean Square Error (RMSE). The result showed that local modified SAVI with R²= 0.767 and RMSE= 0.174 was the best index to produce monthly wheat Kc maps.

Keywords: crop coefficient, remote sensing, vegetation indices, wheat

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994 Robust Method for Evaluation of Catchment Response to Rainfall Variations Using Vegetation Indices and Surface Temperature

Authors: Revalin Herdianto

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Recent climate changes increase uncertainties in vegetation conditions such as health and biomass globally and locally. The detection is, however, difficult due to the spatial and temporal scale of vegetation coverage. Due to unique vegetation response to its environmental conditions such as water availability, the interplay between vegetation dynamics and hydrologic conditions leave a signature in their feedback relationship. Vegetation indices (VI) depict vegetation biomass and photosynthetic capacity that indicate vegetation dynamics as a response to variables including hydrologic conditions and microclimate factors such as rainfall characteristics and land surface temperature (LST). It is hypothesized that the signature may be depicted by VI in its relationship with other variables. To study this signature, several catchments in Asia, Australia, and Indonesia were analysed to assess the variations in hydrologic characteristics with vegetation types. Methods used in this study includes geographic identification and pixel marking for studied catchments, analysing time series of VI and LST of the marked pixels, smoothing technique using Savitzky-Golay filter, which is effective for large area and extensive data. Time series of VI, LST, and rainfall from satellite and ground stations coupled with digital elevation models were analysed and presented. This study found that the hydrologic response of vegetation to rainfall variations may be shown in one hydrologic year, in which a drought event can be detected a year later as a suppressed growth. However, an annual rainfall of above average do not promote growth above average as shown by VI. This technique is found to be a robust and tractable approach for assessing catchment dynamics in changing climates.

Keywords: vegetation indices, land surface temperature, vegetation dynamics, catchment

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993 Aquatic Intervention Research for Children with Autism Spectrum Disorders

Authors: Mehmet Yanardag, Ilker Yilmaz

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Children with autism spectrum disorders (ASD) enjoy and success the aquatic-based exercise and play skills in a pool instead of land-based exercise in a gym. Some authors also observed that many children with ASD experience more success in attaining movement skills in aquatic environment. Properties of the water and hydrodynamic principles cause buoyancy of the water and decrease effects of gravity and it leads to allow a child to practice important aquatic skills with limited motor skills. Also, some authors experience that parents liked the effects of the aquatic intervention program on children with ASD such as improving motor performance, movement capacity and learning basic swimming skills. The purpose of this study was to investigate the effects of aquatic exercise training on water orientation and underwater working capacity were measured in the pool. This study included in four male children between 5 and 7 years old with ASD and 6.25±0.5 years old. Aquatic exercise skills were applied by using one of the error less teaching which is called the 'most to least prompt' procedure during 12-week, three times a week and 60 minutes a day. The findings of this study indicated that there were improvements test results both water orientation skill and underwater working capacity of children with ASD after 12-weeks exercise training. It was seen that the aquatic exercise intervention would be affected to improve working capacity and orientation skills with the special education approaches applying children with ASD in multidisciplinary team-works.

Keywords: aquatic, autism, orientation, ASD, children

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992 Reducing Metabolism Residues in Maintenance Goldfish (Carrasius auratus auratus) by Phytoremediation Plant

Authors: Anna Nurkhasanah, Hamzah Muhammad Ihsan, Nurul Wulandari

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Water quality affects the body condition of aquatic organisms. One of the methods to manage water quality, usually called phytoremediation, involves using aquatic plants. The purpose of this study is to find out the best aquatic plants to reducing metabolism residues from aquatic organism. 5 aquariums (40x30x30 cm) containing 100 grams from each 4 different plants such as water hyacinth (Eichhornia crassipes), salvinia (Salvinia molesta), cabomba (Cabomba caroliniana), and hydrilla (Hydrilla verticillata), thirteen goldfis (Carrasius auratus auratus) are maintained. The maintenance is conducted through a week and water quality measurements are performed three times. The results show that pH value tends to range between 7,22-8,72. The temperature varies between 25-26 °C. DO values varies between 5,2-10,5 mg/L. Amoniac value is between 0,005–5,2 mg/L. Nitrite value is between 0,005 mg/L-2,356 mg/L. Nitrate value is between 0,791 mg/L-1,737 mg/L. CO2 value is between 2,2 mg/L-6,1 mg/L. The result of survival rate of goldfish for all treatments is 100%. Based on this study, the best aquatic plant to reduce metabolism residues is hydrilla.

Keywords: phytoremediation, goldfish, aquatic plants, water quality

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991 The Impacts Of Hydraulic Conditions On The Fate, Transport And Accumulation Of Microplastics Pollution In The Aquatic Ecosystems

Authors: Majid Rasta, Xiaotao Shi, Mian Adnan Kakakhel, Yanqin Bai, Lao Liu, Jia Manke

Abstract:

Microplastics (MPs; particles <5 mm) pollution is considered as a globally pervasive threat to aquatic ecosystems, and many studies reported this pollution in rivers, wetlands, lakes, coastal waters and oceans. In the aquatic environments, settling and transport of MPs in water column and sediments are determined by different factors such as hydrologic characteristics, watershed pattern, rainfall events, hydraulic conditions, vegetation, hydrodynamics behavior of MPs, and physical features of particles (shape, size and density). In the meantime, hydraulic conditions (such as turbulence, high/low water speed flows or water stagnation) play a key role in the fate of MPs in aquatic ecosystems. Therefore, this study presents a briefly review on the effects of different hydraulic conditions on the fate, transport and accumulation of MPs in aquatic ecosystems. Generally, MPs are distributed horizontally and vertically in aquatic environments. The vertical distribution of MPs in the water column changes with different flow velocities. In the riverine, turbulent flow causing from the rapid water velocity and shallow depth may create a homogeneous mixture of MPs throughout the water column. While low velocity followed by low-turbulent waters can lead to the low level vertical mixing of MP particles in the water column. Consequently, the high numbers of MPs are expected to be found in the sediments of deep and wide channels as well as estuaries. In contrast, observing the lowest accumulation of MP particles in the sediments of straights of the rivers, places with the highest flow velocity is understandable. In the marine environment, hydrodynamic factors (e.g., turbulence, current velocity and residual circulation) can affect the sedimentation and transportation of MPs and thus change the distribution of MPs in the marine and coastal sediments. For instance, marine bays are known as the accumulation area of MPs due to poor hydrodynamic conditions. On the other hand, in the nearshore zone, the flow conditions are highly complex and dynamic. Experimental studies illustrated that maximum horizontal flow velocity in the sandy beach can predict the accumulation of MPs so that particles with high sinking velocities deposit in the lower water depths. As a whole, it can be concluded that the transport and accumulation of MPs in aquatic ecosystems are highly affected by hydraulic conditions. This study provided information about the impacts of hydraulic on MPs pollution. Further research on hydraulics and its relationship to the accumulation of MPs in aquatic ecosystems is needed to increase insights into this pollution.

Keywords: microplastics pollution, hydraulic, transport, accumulation

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990 Hazardous Vegetation Detection in Right-Of-Way Power Transmission Lines in Brazil Using Unmanned Aerial Vehicle and Light Detection and Ranging

Authors: Mauricio George Miguel Jardini, Jose Antonio Jardini

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Transmission power utilities participate with kilometers of circuits, many with particularities in terms of vegetation growth. To control these rights-of-way, maintenance teams perform ground, and air inspections, and the identification method is subjective (indirect). On a ground inspection, when identifying an irregularity, for example, high vegetation threatening contact with the conductor cable, pruning or suppression is performed immediately. In an aerial inspection, the suppression team is mobilized to the identified point. This work investigates the use of 3D modeling of a transmission line segment using RGB (red, blue, and green) images and LiDAR (Light Detection and Ranging) sensor data. Both sensors are coupled to unmanned aerial vehicle. The goal is the accurate and timely detection of vegetation along the right-of-way that can cause shutdowns.

Keywords: 3D modeling, LiDAR, right-of-way, transmission lines, vegetation

Procedia PDF Downloads 129
989 Application of Rapid Eye Imagery in Crop Type Classification Using Vegetation Indices

Authors: Sunita Singh, Rajani Srivastava

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For natural resource management and in other applications about earth observation revolutionary remote sensing technology plays a significant role. One of such application in monitoring and classification of crop types at spatial and temporal scale, as it provides latest, most precise and cost-effective information. Present study emphasizes the use of three different vegetation indices of Rapid Eye imagery on crop type classification. It also analyzed the effect of each indices on classification accuracy. Rapid Eye imagery is highly demanded and preferred for agricultural and forestry sectors as it has red-edge and NIR bands. The three indices used in this study were: the Normalized Difference Vegetation Index (NDVI), the Green Normalized Difference Vegetation Index (GNDVI), and the Normalized Difference Red Edge Index (NDRE) and all of these incorporated the Red Edge band. The study area is Varanasi district of Uttar Pradesh, India and Radial Basis Function (RBF) kernel was used here for the Support Vector Machines (SVMs) classification. Classification was performed with these three vegetation indices. The contribution of each indices on image classification accuracy was also tested with single band classification. Highest classification accuracy of 85% was obtained using three vegetation indices. The study concluded that NDRE has the highest contribution on classification accuracy compared to the other vegetation indices and the Rapid Eye imagery can get satisfactory results of classification accuracy without original bands.

Keywords: GNDVI, NDRE, NDVI, rapid eye, vegetation indices

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988 Influence of Physicochemical Water Quality Parameters on Abundance of Aquatic Insects in Rivers of Perak, Malaysia

Authors: Nur Atirah Hasmi, Nadia Nisha Musa, Hasnun Nita Ismail, Zulfadli Mahfodz

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The effect of water quality parameters on the abundance of aquatic insects has been studied in Batu Berangkai, Dipang, Kuala Woh and Lata Kinjang Rivers, Perak, northern peninsular Malaysia. The focuses are to compare the abundance of aquatic insects in each sampling areas and to investigate the physical and chemical factors (water temperature, depth of water, canopy, water velocity, pH value, and dissolved oxygen) on the abundance of aquatic insects. The samples and data were collected by using aquatic net and multi-probe parameter. Physical parameters; water velocity, water temperature, depth, canopy cover, and two chemical parameters; pH value and dissolved oxygen have been measured in situ and recorded. A total of 631 individuals classified into 6 orders and 18 families of aquatic insects were identified from four sampling sites. The largest percentage of samples collected is from order Plecoptera 35.8%, followed by Ephemeroptera 32.6%, Trichoptera 17.0%, Hemiptera 8.1%, Coleoptera 4.8%, and the least is Odonata 1.7%. The aquatic insects collected from Dipang River have the highest abundance of 273 individuals from 6 orders and 13 families and the least insects trapped at Lata Kinjang which only have 64 individuals from 5 orders and 6 families. There is significant association between different sampling areas and abundance of aquatic insects (p<0.05). High abundance of aquatic insects was found in higher water temperature, low water velocity, deeper water, low pH, high amount of dissolved oxygen, and the area that is not covered by canopy.

Keywords: aquatic insect, physicochemical parameter, river, water quality

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987 Image Processing and Calculation of NGRDI Embedded System in Raspberry

Authors: Efren Lopez Jimenez, Maria Isabel Cajero, J. Irving-Vasqueza

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The use and processing of digital images have opened up new opportunities for the resolution of problems of various kinds, such as the calculation of different vegetation indexes, among other things, differentiating healthy vegetation from humid vegetation. However, obtaining images from which these indexes are calculated is still the exclusive subject of active research. In the present work, we propose to obtain these images using a low cost embedded system (Raspberry Pi) and its processing, using a set of libraries of open code called OpenCV, in order to obtain the Normalized Red-Green Difference Index (NGRDI).

Keywords: Raspberry Pi, vegetation index, Normalized Red-Green Difference Index (NGRDI), OpenCV

Procedia PDF Downloads 290
986 2D Surface Flow Model in The Biebrza Floodplain

Authors: Dorota Miroslaw-Swiatek, Mateusz Grygoruk, Sylwia Szporak

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We applied a two-dimensional surface water flow model with irregular wet boundaries. In this model, flow equations are in the form of a 2-D, non-linear diffusion equations which allows to account spatial variations in flow resistance and topography. Calculation domain to simulate the flow pattern in the floodplain is congruent with a Digital Elevation Model (DEM) grid. The rate and direction of sheet flow in wetlands is affected by vegetation type and density, therefore the developed model take into account spatial distribution vegetation resistance to the water flow. The model was tested in a part of the Biebrza Valley, of an outstanding heterogeneity in the elevation and flow resistance distributions due to various ecohydrological conditions and management measures. In our approach we used the highest-possible quality of the DEM in order to obtain hydraulic slopes and vegetation distribution parameters for the modelling. The DEM was created from the cloud of points measured in the LiDAR technology. The LiDAR reflects both the land surface as well as all objects on top of it such as vegetation. Depending on the density of vegetation cover the ability of laser penetration is variable. Therefore to obtain accurate land surface model the “vegetation effect” was corrected using data collected in the field (mostly the vegetation height) and satellite imagery such as Ikonos (to distinguish different vegetation types of the floodplain and represent them spatially). Model simulation was performed for the spring thaw flood in 2009.

Keywords: floodplain flow, Biebrza valley, model simulation, 2D surface flow model

Procedia PDF Downloads 497
985 Urban Vegetation as a Mitigation Strategy for Urban Heat Island Effect a Case of Kerala

Authors: Athul T.

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Kerala cities in India are grappling with an alarming rise in temperatures fueled by the Urban Heat Island (UHI) effect. This phenomenon, exacerbated by rapid urbanization and climate change, poses a significant threat to public health and environmental well-being. In response to this growing concern, this study investigates the potential of urban vegetation as a powerful mitigation strategy against UHI. The study delves into the intricate relationship between micro-climate changes, UHI intensity, and the strategic placement of greenery in alleviating these effects. Utilizing advanced simulation software, the most effective vegetation types and configurations for maximizing UHI reduction will be identified. By analyzing the current state of Kozhikode's urban vegetation and its influence on microclimates, this study aims to tailor actionable strategies for Kerala cities, potentially paving the way for a more sustainable and thermally comfortable urban future.

Keywords: urban heat island, climate change, micro climate, urban vegetation

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984 Experiment on Artificial Recharge of Groundwater Implemented Project: Effect on the Infiltration Velocity by Vegetation Mulch

Authors: Cheh-Shyh Ting, Jiin-Liang Lin

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This study was conducted at the Wanglung Farm in Pingtung County to test the groundwater seepage influences on the implemented project for artificial groundwater recharge. The study was divided into three phases. The first phase, conducted on natural groundwater that was recharged through the local climate and growing conditions, observed the natural form of vegetation species. The original plants were flooded, and after 60 days it was observed that of the original plants only Goosegrass (Eleusine indica) and Black heart (Polygonum lapathifolium Linn.) remained. Direct infiltration tests were carried out, and calculations for the effect of vegetation on infiltration velocity of the recharge pool were noted. The second phase was an indoor test. Bahia grass and wild amaranth were selected as vegetation roots. After growth, the distribution of different grassroots was observed in order to facilitate a comparison permeability coefficient calculated by the amount of penetration and to explore the relationship between density and the efficiency to groundwater recharge. The third phase was the root tomography analysis, further observation of the development of plant roots using computed tomography technology. Computed Tomography, also known as (CT), is a diagnostic imaging examination, normally used in the medical field. In the first phase of the feasibility study, most non-aquatic plants wilted and died within seven days. In seven days, the remaining plants were used for experimental infiltration analysis. Results showed that in eight hours of infiltration test, Eleusine indica stems averaged 0.466 m/day and wild amaranth averaged 0.014 m/day. The second phase of the experiment was conducted on the remains of the plant a week in it had died and rotted, and the infiltration experiment was performed under these conditions. The results showed eight hours in end of the infiltration test, Eleusine indica stems averaged 0.033 m/day, and wild amaranth averaged 0.098 m/day. Non-aquatic plants died within two weeks, and their rotted remains clogged the pores of bottom soil particles, causing obstruction of recharge pool infiltration. Experiment results showed that eight hours in the test the average infiltration velocity for Eleusine indica stems was 0.0229 m/day and wild amaranth averaged 0.0117 m/day. Since the rotted roots of the plants blocked the pores of the soil in the recharge pool, which resulted in the obstruction of the artificial infiltration pond and showed an immediate impact on recharge efficiency. In order to observe the development of plant roots, the third phase used computed tomography imaging. Iodine developer was injected into the Black heart, allowing its cross-sectional images to be shown on CT and to be used to observe root development.

Keywords: artificial recharge of groundwater, computed tomography, infiltration velocity, vegetation root system

Procedia PDF Downloads 309