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عنوان فارسی مقاله:
ارزیابی سیستم هیدرو صوتی ساده برای نقشه برداری از ماکروفیتها در تالاب بسیار کم عمق و گل آلود
عنوان انگلیسی مقاله:
Assessment of a simple hydroacoustic system for the mapping of macrophytes in extremely shallow and turbid lagoon
سال انتشار : 2016
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مقدمه انگلیسی مقاله:
1. Introduction
Shallow coastal waters and estuaries usually are strongly impacted by human-induced eutrophication. In such conditions submerged macrophytes are often replaced by faster growing benthic macroalgae and phytoplankton (Duarte, 1995), and maximum colonization depth of macrophytes is decreased due to reduced light climate near a bottom (Dennison et al., 1993). For this reason, species composition, distribution and abundance of submerged macrophytes are generally considered as water quality indicators under Water Framework Directive (WFD, 2000/60/EC). For example, charophytes are generally considered important indicators of good ecological status in the coastal waters (e.g. Schubert and Blindow, 2003; Selig et al., 2007; Hansen and Snickars, 2014). Established manual techniques for characterising and monitoring aquatic vegetation are both time consuming and labourintensive, and generate observations of very limited spatial extent (Winfield et al., 2007). Such methods as aerial surveys or underwater camera systems provide relatively large-scale assessments of spatial patterns of macrophytes but are highly dependent on waterclarity, roughness of water surface and cloud cover (Madsen, 1993; Hewitt et al., 2004). Hydroacoustic techniques are less dependent on environmental conditions and provide rapid, extensive and spatial referenced data (Winfield et al., 2007). Therefore, this approach receives an increasing attention for the assessment of macrophyte communities. Despite several successful applications of hydroacoustics in the detection and qualitative characterisation of macrophytes (e.g. Xu et al., 2013), there are still limitations (Mielck et al., 2014). For instance, sonars cannot clearly reflect small morphological features of macrophytes, prohibiting the identification to species level even for relatively large kelps (Bajjouk et al., 2015). Fishermen class sonars differ in their technical characteristics, but usually provide side scan sonar data and depth in a single beam-like manner. Although few manufacturers offer proprietary software packages, such as EcoSAV from BioSonic, that are specifi- cally designed to measure plant height, areal coverage and density of macrophytes (Winfield et al., 2007), these solutions are not available for majority of sonar systems. Nonetheless, these characteristics can be estimated manually from echograms, where vegetation is generally visible as a contiguous vertical echo return immediately above the bottom (Depew et al., 2009). Based on the height of echofeatures, the dominant growth form in a stand can be identified (Fortin et al., 1993). For instance, charophytes are usually clarity, roughness of water surface and cloud cover (Madsen, 1993; Hewitt et al., 2004). Hydroacoustic techniques are less dependent on environmental conditions and provide rapid, extensive and spatial referenced data (Winfield et al., 2007). Therefore, this approach receives an increasing attention for the assessment of macrophyte communities. Despite several successful applications of hydroacoustics in the detection and qualitative characterisation of macrophytes (e.g. Xu et al., 2013), there are still limitations (Mielck et al., 2014). For instance, sonars cannot clearly reflect small morphological features of macrophytes, prohibiting the identification to species level even for relatively large kelps (Bajjouk et al., 2015). Fishermen class sonars differ in their technical characteristics, but usually provide side scan sonar data and depth in a single beam-like manner. Although few manufacturers offer proprietary software packages, such as EcoSAV from BioSonic, that are specifi- cally designed to measure plant height, areal coverage and density of macrophytes (Winfield et al., 2007), these solutions are not available for majority of sonar systems. Nonetheless, these characteristics can be estimated manually from echograms, where vegetation is generally visible as a contiguous vertical echo return immediately above the bottom (Depew et al., 2009). Based on the height of echofeatures, the dominant growth form in a stand can be identified (Fortin et al., 1993). For instance, charophytes are usually
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کلمات کلیدی:
Aquatic botany - Terkko Navigator https://www.terkko.helsinki.fi/.../15211701_assessment-of-a-simple... Translate this page Assessment of a simple hydroacoustic system for the mapping of macrophytes in extremely shallow and turbid lagoon. Added 225 days ago (19.08.2016). Marine Science and Technology Centre https://jmtc.ku.lt/index.php?m_id=26&t_id=2&id=11&action...lang... Assessment of a simple hydroacoustic system for the mapping of macrophytes in extremely shallow and turbid lagoon. Aquatic Botany, 134, pp.39-46. Patrício J. Marine Science and Technology Centre https://jmtc.ku.lt/index.php?m_id=26&t_id=2&id=13&action...lang... Assessment of a simple hydroacoustic system for the mapping of macrophytes in extremely shallow and turbid lagoon. Aquatic Botany, 134, pp.39-46. Šiaulys, A. [PDF]A comparison of two hydroacoustic methods for estimating submerged ... www.apms.org/wp/wp-content/uploads/japm-53-02-151.pdf by P RADOMSKI - 2015 - Cited by 2 - Related articles available but different hydroacoustic systems to determine whether ... macrophyte abundance, plant height, and variability in plant height ... heights in shallow waters. In contrast ... considered the most accurate method of estimating plant biomass ..... This system quickly creates maps of dense vegetation when surveyors ... Programme - Universidad de Murcia www.um.es/7eurolag/programme/ 11:30 – Dynamic response of lagoon ecosystems to extreme events (flooding ..... hydroacoustic system for the mapping of macrophytes in extremely shallow and ... Depth limits and minimum light requirements of freshwater macrophytes onlinelibrary.wiley.com/doi/10.1046/j.1365-2427.1997.00183.x/full by AL MIDDELBOE - 1997 - Cited by 251 - Related articles Depth limits and minimum light requirements of freshwater macrophytes ... were independent of light penetration in lakes with very low transparency (Zs < 1 m). ... The relationship between Zc, macrophyte type and lake transparency could be ... hydroacoustic system for the mapping of macrophytes in extremely shallow and ...
