Artykuły w czasopismach na temat „Benthic habitat”
Kliknij ten link, aby zobaczyć inne rodzaje publikacji na ten temat: Benthic habitat.
Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych
Sprawdź 50 najlepszych artykułów w czasopismach naukowych na temat „Benthic habitat”.
Przycisk „Dodaj do bibliografii” jest dostępny obok każdej pracy w bibliografii. Użyj go – a my automatycznie utworzymy odniesienie bibliograficzne do wybranej pracy w stylu cytowania, którego potrzebujesz: APA, MLA, Harvard, Chicago, Vancouver itp.
Możesz również pobrać pełny tekst publikacji naukowej w formacie „.pdf” i przeczytać adnotację do pracy online, jeśli odpowiednie parametry są dostępne w metadanych.
Przeglądaj artykuły w czasopismach z różnych dziedzin i twórz odpowiednie bibliografie.
1
Ridgway, Mark S., i J. D. McPhail. "Rival male effects on courtship behaviour in the Enos Lake species pair of sticklebacks (Gasterosteus)". Canadian Journal of Zoology 65, nr 8 (1.08.1987): 1951–55. http://dx.doi.org/10.1139/z87-297.
Pełny tekst źródłaStreszczenie:
Two species of stickleback (Gasterosteus) coexist in Enos Lake, on Vancouver Island. Field observations and trapping data indicate that limnetic males nest on open substrate whereas benthic males nest on substrate in vegetation. Given these habitat differences, we conducted laboratory experiments to determine the effect of conspecific rival nesting males on the courtship behaviour of the two species. Courtships of limnetic fish were longer in duration than those of benthic fish because of longer territorial interactions between limnetic males. Limnetic females, and not benthic females, reduced their positive responses to their male partner when a rival male was present. The cost of competitive courtship, in terms of male competition and female choice, is thus greater in limnetics than benthics. Differences in competitive courtship between the two species are behavioural adaptations to habitats that promote (open habitat, limnetics) or reduce (vegetation, benthics) courtship disruptions.
2
Osuka, Kennedy, Marc Kochzius, Ann Vanreusel, David Obura i Melita Samoilys. "Linkage between fish functional groups and coral reef benthic habitat composition in the Western Indian Ocean". Journal of the Marine Biological Association of the United Kingdom 98, nr 2 (10.10.2016): 387–400. http://dx.doi.org/10.1017/s0025315416001399.
Pełny tekst źródłaStreszczenie:
Benthic habitat composition is a key factor that structures assemblages of coral reef fishes. However, natural and anthropogenic induced disturbances impact this relationship. This study investigates the link between benthic habitat composition and fish functional groups in four countries in the Western Indian Ocean (WIO). Benthic composition of 32 sites was quantified visually from percentage cover of hard and soft corals, rubble, turf, fleshy and crustose coralline algae. At each site, abundance of 12 coral-associated fish functional groups in 50 × 5 m transects was determined. Cluster analysis characterized reefs based on benthic cover and revealed five habitat types (A, B, C, D and E) typified by decreasing cover of hard corals, increasing cover of turf and/or fleshy algae and differences in benthic diversity. Habitat type A was present in all four countries. Other habitats types showed geographic affiliations: notably Comoros sites clustered in either habitats B or E, northern Madagascar had B, C and D type habitats, whereas sites in central Tanzania and northern Mozambique had habitats D and E. Fish functional groups showed significant linkages with some habitat types. The abundances of corallivores, invertivores, detritivores and grazers were higher in habitat B, whereas planktivores and small excavators showed lower abundances in the same habitat. These linkages between benthic habitat types and fish functional groups are important in informing priority reefs that require conservation and management planning.
3
Mohamed, Hassan, Kazuo Nadaoka i Takashi Nakamura. "Semiautomated Mapping of Benthic Habitats and Seagrass Species Using a Convolutional Neural Network Framework in Shallow Water Environments". Remote Sensing 12, nr 23 (7.12.2020): 4002. http://dx.doi.org/10.3390/rs12234002.
Pełny tekst źródłaStreszczenie:
Benthic habitats are structurally complex and ecologically diverse ecosystems that are severely vulnerable to human stressors. Consequently, marine habitats must be mapped and monitored to provide the information necessary to understand ecological processes and lead management actions. In this study, we propose a semiautomated framework for the detection and mapping of benthic habitats and seagrass species using convolutional neural networks (CNNs). Benthic habitat field data from a geo-located towed camera and high-resolution satellite images were integrated to evaluate the proposed framework. Features extracted from pre-trained CNNs and a “bagging of features” (BOF) algorithm was used for benthic habitat and seagrass species detection. Furthermore, the resultant correctly detected images were used as ground truth samples for training and validating CNNs with simple architectures. These CNNs were evaluated for their accuracy in benthic habitat and seagrass species mapping using high-resolution satellite images. Two study areas, Shiraho and Fukido (located on Ishigaki Island, Japan), were used to evaluate the proposed model because seven benthic habitats were classified in the Shiraho area and four seagrass species were mapped in Fukido cove. Analysis showed that the overall accuracy of benthic habitat detection in Shiraho and seagrass species detection in Fukido was 91.5% (7 classes) and 90.4% (4 species), respectively, while the overall accuracy of benthic habitat and seagrass mapping in Shiraho and Fukido was 89.9% and 91.2%, respectively.
4
Hamidah, M., R. A. Pasaribu i F. A. Aditama. "Benthic habitat mapping using Object-Based Image Analysis (OBIA) on Tidung Island, Kepulauan Seribu, DKI Jakarta". IOP Conference Series: Earth and Environmental Science 944, nr 1 (1.12.2021): 012035. http://dx.doi.org/10.1088/1755-1315/944/1/012035.
Pełny tekst źródłaStreszczenie:
Abstract Tidung Island is one of the islands in Kepulauan Seribu, DKI Jakarta, Indonesia. This island has various benthic that live on the coastal areas, and benthic habitat has various functions both ecologically and economically. Nowadays, remote sensing technology is one way to detect benthic habitats in coastal areas. Mapping benthic habitat is essential for sustainable coastal resource management and to predict the distribution of benthic organisms. This study aims to map the benthic habitats using the object-based image analysis (OBIA) and calculate the accuracy of benthic habitat classification results in Tidung Island, Kepulauan Seribu, DKI Jakarta. The field data were collected on June 2021, and the image data used is satellite Sentinel-2 imagery acquired in June 2021. The result shows that the benthic habitat classification was produced in 4 classes: seagrass, rubble, sand, and live coral. The accuracy test result obtained an overall accuracy (OA) of 74.29% at the optimum value of the MRS segmentation scale 15;0,1;0.7 with the SVM algorithm. The results of benthic habitat classification show that the Seagrass class dominates the shallow water area at the research site with an area of 118.77 ha followed by Life Coral 104.809 ha, Sand 43.352 ha, and the smallest area is the Rubble class of 42.28 Ha.
5
Sevastou, K., N. Lampadariou, P. N. Polymenakou i A. Tselepides. "Benthic communities in the deep Mediterranean Sea: exploring microbial and meiofaunal patterns in slope and basin ecosystems". Biogeosciences 10, nr 7 (18.07.2013): 4861–78. http://dx.doi.org/10.5194/bg-10-4861-2013.
Pełny tekst źródłaStreszczenie:
Abstract. The long-held perception of the deep sea consisting of monotonous slopes and uniform oceanic basins has over the decades given way to the idea of a complex system with wide habitat heterogeneity. Under the prism of a highly diverse environment, a large dataset was used to describe and compare spatial patterns of the dominant small-size components of deep-sea benthos, metazoan meiofauna and microbes, from Mediterranean basins and slopes. A grid of 73 stations sampled at five geographical areas along the central-eastern Mediterranean Basin (central Mediterranean, northern Aegean Sea, Cretan Sea, Libyan Sea, eastern Levantine) spanning over 4 km in depth revealed a high diversity, irrespective of the benthic group or level of taxonomic analysis. A common decreasing bathymetric trend was detected for meiobenthic abundance, major taxa diversity and nematode genera richness, but no differences were found between the two habitats (basin vs slope). In contrast, microbial richness is significantly higher at the basin ecosystem and tends to increase with depth. Multivariate analyses (β- and δ-diversity and ordination analysis) complemented these results and underlined the high within-habitat variability of benthic communities. Meiofaunal communities in particular were found to change gradually and vary more towards the abyss. On the other hand, microbial communities were highly variable, even among samples of the same area, habitat and bathymetry. A significant proportion of the variation of benthic communities and their descriptors was explained by depth and proxies of food availability (sedimentary pigments and organic content), but the combination of predictor variables and the strength of the relationship varied depending on the data set used (based on type of habitat, benthic component, taxonomic level). This, along with the observed high within-habitat variability suggests that other factors, which tend to vary at local scale (hydrodynamics, substrate structure, geochemistry, food quality, etc.), may also relate to the observed benthic patterns. Overall, the results presented here suggest that differences in small-size benthos between the basin and slope habitats are neither strong nor consistent; it appears that within-habitat variability is high, differences among depth ranges are important and further investigation of possible environmental drivers of benthic patterns is needed.
6
Ramah, Sundy, Gilberte Gendron, Ranjeet Bhagooli, Mouneshwar Soondur, Andrew Souffre, Rodney Melanie, Priscilla Coopen, Luvna Caussy, Dass Bissessur i Odd A. Bergstad. "Diversity and distribution of the shallow water (23-50 m) benthic habitats on the Saya de Malha Bank, Mascarene Plateau". Western Indian Ocean Journal of Marine Science, nr 2/2021 (20.07.2022): 69–80. http://dx.doi.org/10.4314/wiojms.si2021.2.5.
Pełny tekst źródłaStreszczenie:
The Saya de Malha Bank (SMB) is one of the largest and least studied marine banks on the Mascarene Plateau. This study aimed to examine the diversity and distribution of the main benthic habitats in the shallow waters of the SMB (23 to 50 m). The survey was carried out in May 2018 during the EAF-Nansen Indian Ocean Research Expedition using a Remotely Operated Vehicle (ROV) deployed at 15 stations. Four main benthic habitats were investigated and their relative abundance determined during the survey. The 143,110 m2 surveyed area revealed proportional benthic habitat cover of 43.6 ± 22.4, 24.5 ± 21.9, 21.2 ± 27.8, and 10.5 ± 12.6 % for seaweed, abiotic substrate, seagrasses and corals, respectively. The seaweed habitat (43.6 %) was mainly composed of Halimeda spp. It represented up to 77 % of the habitats observed at SS34 (4553 m2). Even though seaweeds are considered seasonal, their dominance at all stations creates an important habitat structure for many organisms. The seagrass habitat (21.2 %) was dominated by Thalassodendron ciliatum. This habitat covered up to 93 % of the area investigated at SS38 (5950 m2) and was found mainly on the eastern side of the bank. The live hard coral habitat (10.5 %) was the highest at SS36-2 (35% of 9819 m2) and was more homogenously spread within the shallow areas. The unstable and the stable bare bottom substrate habitat (24.7 %) characterized as abiotic habitat was mainly composed of bedrock, sand, and rubble. It dominated at SS42 where it constituted 72.5 % of the 5114 m2 investigated and was recorded at all stations. Further research is warranted to better understand the diversity and the distribution of benthic habitats within the shallow waters of the SMB, along with collection of targeted benthic organisms for identification at higher taxonomic levels, to better formulate conservation and management measures and strategies.
7
Alifatri, La Ode, Bayu Prayudha i Kasih Anggraini. "Klasifikasi Habitat Bentik Berdasarkan Citra Sentinel-2 di Kepulauan Kei, Maluku Tenggara". Jurnal Ilmu Pertanian Indonesia 27, nr 3 (1.07.2022): 372–84. http://dx.doi.org/10.18343/jipi.27.3.372.
Pełny tekst źródłaStreszczenie:
Imagery classification has long been used in analyzing remote sensing data. The use of the classification algorithm model can affect the results in interpreting benthic habitats in shallow water. This study aimed to determine the best classification algorithm model for mapping benthic habitat cover through Sentinel-2 satellite imagery. Three algorithm models were employed: Maximum Likelihood Classification (MLC), Minimum Distance Classification (MDC), and Mahalanobis Distance Classification (MaDC). The benthic habitat types were extracted using Lyzenga correction, giving three categories: coral, seagrass, and sand. The results showed that the application algorithm models of the MLC, MDC, and MaDC on the benthic habitat mapping resulted in an accuracy value that was not significantly different at the 95% confidence interval. However, of the three algorithms used, the MaDC algorithm provides the best results in overall accuracy (78.35%) than the MDC (74.45%) and the MLC (74.33%). It shows that the MaDC algorithm can be referred to as the mapped benthic habitat cover in the Kei Islands. However, this algorithm model needs to be continuously studied and compared to other models in other locations.
Keywords: benthic, habitat classification, Kei Islands, sentinel
8
Kocheshkova, Оlga, Еlena Ezhov, Dmitry Dorokhov i Evgenia Dorokhova. "Benthic communities and habitats in the near shore zone of the Curonian Spit (the south–eastern part of the Baltic Sea)". Baltica 27, special (20.02.2014): 45–54. http://dx.doi.org/10.5200/baltica.2014.27.15.
Pełny tekst źródłaStreszczenie:
Benthic communities classified according to species diversity, abundance and composition of dominant complex were defined and mapped. Maps compiled represent the distribution of bottom sediment types, substrata, bathymetry and benthic communities in the pilot area. Combination of data on community distribution and several abiotic habitat features (grain size, substrate types, and photic conditions) allowed recognizing several benthic habitats, according to HELCOM habitat classification. New data on features of coastal benthic biotopes made evident the existence of unique seascape “ancient lagoon mud” in the study area and allowed recommending further establishment of new marine protected areas.
9
Walton, Mark E. M., Jamie Hayes, Mohsin Al-Ansi, Mohamed Abdallah, Ibrahim Al Maslamani, Mohammed Al-Mohannadi, Ismail Al-Shaikh i in. "Towards spatial management of fisheries in the Gulf: benthic diversity, habitat and fish distributions from Qatari waters". ICES Journal of Marine Science 75, nr 1 (27.07.2017): 178–89. http://dx.doi.org/10.1093/icesjms/fsx116.
Pełny tekst źródłaStreszczenie:
Abstract As with many other regions in the world, more complete information on the distribution of marine habitats in the Gulf is required to inform environmental policy, and spatial management of fisheries resources will require better understanding of the relationships between habitat and fish communities. Towed cameras and sediment grabs were used to investigate benthic habitats and associated epifauna, infauna and fish communities in the central Gulf, offshore from the east coast of Qatar, in water depths of between 12 and 52 m. Six different habitats were identified: (i) soft sediment habitats of mud and (ii) sand, and structured habitats of (iii) macro-algal reef, (iv) coral reef, (v) mixed reef, and (vi) oyster bed. The epibenthic community assemblage of the mud habitat was significantly different to that of sand, which in turn differed from the structured habitats of coral reef, mixed reef and oyster bed, with the macroalgal assemblage having similarities to both sand and the other structured habitats. Fish assemblages derived from video data did not differ between habitats, although certain species were only associated with particular habitats. Epibenthic diversity indices were significantly lower in mud, sand and macro-algal habitats, with no differences recorded for fish diversity. Soft sediment grab samples indicated that mud habitats had the highest benthic diversity, with Shannon-Weiner values of >4, and were more diverse than sand with values of 3.3. The study demonstrates high biodiversity in benthic habitats in the central and southwestern Gulf, which may in part be due to the absence of trawling activity in Qatari waters. There is a strong influence of depth on benthic habitat type, so that depth can be used to predict habitat distribution with a high level of accuracy. The presence of outcrops of hard substrata creates a mosaic of patchy shallow structured benthic habitat across extensive areas of the offshore seabed. Such heterogeneity, and the association of commercially exploited fish species with specific habitats, indicates that this region is well suited to a spatial approach to fisheries management.
10
Bowles, David E., i Leroy J. Kleinsasser. "Environmental Determinates of Distribution for Dragonfly Nymphs (Odonata: Anisoptera) in Urban and Non-Urban East Texas Streams, USA". Hydrobiology 1, nr 1 (1.01.2022): 76–88. http://dx.doi.org/10.3390/hydrobiology1010006.
Pełny tekst źródłaStreszczenie:
We collected environmental and habitat data for nymphs of 12 dragonfly species (Odonata: Anisoptera) from 91 stream sites throughout eastern Texas, including urban and non-urban locations. Understanding the relationship of dragonflies to habitat structure and other environmental variables is crucial for the purpose of conserving these insects and better using them as predictive tools for water quality assessments, and refining tolerance values. The objectives of this study were to determine the key environmental variables influencing the diversity and distribution of dragonflies in eastern Texas streams, and further determine if differences in those factors could be observed between urban and nonurban sites. We collected samples separately from benthic habitats and woody snag habitats. Significantly fewer sites were observed to have dragonfly species on snag habitat (mean = 1.25) compared to benthic samples (mean = 14.67) (t-test, p = 0.001). The number of dragonfly species collected among non-urban streams (mean = 9.83) was not significantly different than urban streams (mean = 6.08; t-test, p = 0.07). Detrended correspondence analysis of benthic and snag habitat data collected from non-urban and urban locations showed that most of the species are oriented most closely to benthic habitats in non-urban streams. Snag habitat was shown to be poorly ordinated for all of the species. A canonical correspondence analysis of 29 water quality and habitat variables as environmental determinants of dragonfly diversity and distribution showed that distributional relationships among species are complex and often described by multiple environmental factors.
11
Mohamed, Hassan, Kazuo Nadaoka i Takashi Nakamura. "Automatic Semantic Segmentation of Benthic Habitats Using Images from Towed Underwater Camera in a Complex Shallow Water Environment". Remote Sensing 14, nr 8 (9.04.2022): 1818. http://dx.doi.org/10.3390/rs14081818.
Pełny tekst źródłaStreszczenie:
Underwater image segmentation is useful for benthic habitat mapping and monitoring; however, manual annotation is time-consuming and tedious. We propose automated segmentation of benthic habitats using unsupervised semantic algorithms. Four such algorithms––Fast and Robust Fuzzy C-Means (FR), Superpixel-Based Fast Fuzzy C-Means (FF), Otsu clustering (OS), and K-means segmentation (KM)––were tested for accuracy for segmentation. Further, YCbCr and the Commission Internationale de l’Éclairage (CIE) LAB color spaces were evaluated to correct variations in image illumination and shadow effects. Benthic habitat field data from a geo-located high-resolution towed camera were used to evaluate proposed algorithms. The Shiraho study area, located off Ishigaki Island, Japan, was used, and six benthic habitats were classified. These categories were corals (Acropora and Porites), blue corals (Heliopora coerulea), brown algae, other algae, sediments, and seagrass (Thalassia hemprichii). Analysis showed that the K-means clustering algorithm yielded the highest overall accuracy. However, the differences between the KM and OS overall accuracies were statistically insignificant at the 5% level. Findings showed the importance of eliminating underwater illumination variations and outperformance of the red difference chrominance values (Cr) in the YCbCr color space for habitat segmentation. The proposed framework enhanced the automation of benthic habitat classification processes.
12
Wicaksono, Pramaditya, Prama Ardha Aryaguna i Wahyu Lazuardi. "Benthic Habitat Mapping Model and Cross Validation Using Machine-Learning Classification Algorithms". Remote Sensing 11, nr 11 (29.05.2019): 1279. http://dx.doi.org/10.3390/rs11111279.
Pełny tekst źródłaStreszczenie:
This research was aimed at developing the mapping model of benthic habitat mapping using machine-learning classification algorithms and tested the applicability of the model in different areas. We integrated in situ benthic habitat data and image processing of WorldView-2 (WV2) image to parameterise the machine-learning algorithm, namely: Random Forest (RF), Classification Tree Analysis (CTA), and Support Vector Machine (SVM). The classification inputs are sunglint-free bands, water column corrected bands, Principle Component (PC) bands, bathymetry, and the slope of underwater topography. Kemujan Island was used in developing the model, while Karimunjawa, Menjangan Besar, and Menjangan Kecil Islands served as test areas. The results obtained indicated that RF was more accurate than any other classification algorithm based on the statistics and benthic habitats spatial distribution. The maximum accuracy of RF was 94.17% (4 classes) and 88.54% (14 classes). The accuracies from RF, CTA, and SVM were consistent across different input bands for each classification scheme. The application of RF model in the classification of benthic habitat in other areas revealed that it is recommended to make use of the more general classification scheme in order to avoid several issues regarding benthic habitat variations. The result also established the possibility of mapping a benthic habitat without the use of training areas.
13
Nababan, Bisman, La Ode Khairum Mastu, Nurul Hazrina Idris i James P. Panjaitan. "Shallow-Water Benthic Habitat Mapping Using Drone with Object Based Image Analyses". Remote Sensing 13, nr 21 (5.11.2021): 4452. http://dx.doi.org/10.3390/rs13214452.
Pełny tekst źródłaStreszczenie:
Spatial information on benthic habitats in Wangiwangi island waters, Wakatobi District, Indonesia was very limited in recent years. However, this area is one of the marine tourism destinations and one of the Indonesia’s triangle coral reef regions with a very complex coral reef ecosystem. The drone technology that has rapidly developed in this decade, can be used to map benthic habitats in this area. This study aimed to map shallow-water benthic habitats using drone technology in the region of Wangiwangi island waters, Wakatobi District, Indonesia. The field data were collected using a 50 × 50 cm squared transect of 434 observation points in March–April 2017. The DJI Phantom 3 Pro drone with a spatial resolution of 5.2 × 5.2 cm was used to acquire aerial photographs. Image classifications were processed using object-based image analysis (OBIA) method with contextual editing classification at level 1 (reef level) with 200 segmentation scale and several segmentation scales at level 2 (benthic habitat). For level 2 classification, we found that the best algorithm to map benthic habitat was the support vector machine (SVM) algorithm with a segmentation scale of 50. Based on field observations, we produced 12 and 9 benthic habitat classes. Using the OBIA method with a segmentation value of 50 and the SVM algorithm, we obtained the overall accuracy of 77.4% and 81.1% for 12 and 9 object classes, respectively. This result improved overall accuracy up to 17% in mapping benthic habitats using Sentinel-2 satellite data within the similar region, similar classes, and similar method of classification analyses.
14
Fukunaga, Atsuko, Randall K. Kosaki, Kailey H. Pascoe i John H. R. Burns. "Fish Assemblage Structure in the Northwestern Hawaiian Islands Is Associated with the Architectural Complexity of Coral-Reef Habitats". Diversity 12, nr 11 (15.11.2020): 430. http://dx.doi.org/10.3390/d12110430.
Pełny tekst źródłaStreszczenie:
The architectural complexity of coral-reef habitat plays an important role in determining the assemblage structure of reef fish. We investigated associations between the reef habitats and fish assemblages in the Northwestern Hawaiian Islands (NWHI) using in situ fish counts and data on habitat metrics and benthic community composition that were obtained from three-dimensional (3D) photogrammetric reconstructions of the surveyed sites. The structure of fish assemblage as a whole on the basis of Bray–Curtis dissimilarity, species richness and the abundances of herbivores and piscivores were associated with habitat metrics, with higher levels of architectural complexity generally supporting greater numbers of fish species and individuals. Benthic cover did not explain additional variation in these variables after the effects of habitat metrics were taken into account. Corallivorous fish was the only group that showed positive associations with both habitat metrics and benthic cover (Acropora and Pocillopora corals). The total fish abundance and the abundances of planktivores and invertivores did not show associations with either habitat metrics or benthic cover. This study suggests that an appropriate combination of habitat metrics can be used to account sufficiently for the effects of habitat architecture on fish assemblages in reef monitoring efforts in the NWHI.
15
Li, Jiwei, Steven R. Schill, David E. Knapp i Gregory P. Asner. "Object-Based Mapping of Coral Reef Habitats Using Planet Dove Satellites". Remote Sensing 11, nr 12 (18.06.2019): 1445. http://dx.doi.org/10.3390/rs11121445.
Pełny tekst źródłaStreszczenie:
High spatial resolution benthic habitat information is essential for coral reef protection and coastal environmental management. Satellite-based shallow benthic composition mapping offers a more efficient approach than traditional field measurements, especially given the advancements in high spatial and temporal resolution satellite imagery. The Planet Dove satellite constellation now has more than 150 instruments in orbit that offer daily coverage at high spatial resolution (3.7 m). The Dove constellation provides regularly updated imagery that can minimize cloud in tropical oceans where dense cloud cover persists. Daily image acquisition also provides an opportunity to detect time-sensitive changes in shallow benthic habitats following coral bleaching events, storms, and other disturbances. We developed an object-based coral reef habitat mapping approach for Dove and similar multispectral satellites that provides bathymetry estimation, bottom reflectance retrieval, and object-based classification to identify different benthic compositions in shallow coastal environments. We tested our approach in three study sites in the Dominican Republic using 18 Dove images. Benthic composition classification results were validated by field measurements (overall accuracy = 82%). Bathymetry and bottom reflectance significantly contributed to identifying benthic habitat classes with similar surface reflectance. This new object-based approach can be effectively applied to map and manage coral reef habitats.
16
Nandika, Muhammad Rizki, Azura Ulfa, Andi Ibrahim i Anang Dwi Purwanto. "Assessing the Shallow Water Habitat Mapping Extracted from High-Resolution Satellite Image with Multi Classification Algorithms". Geomatics and Environmental Engineering 17, nr 2 (30.01.2023): 69–87. http://dx.doi.org/10.7494/geom.2023.17.2.69.
Pełny tekst źródłaStreszczenie:
Remote sensing technology is reliable in identifying the distribution of seabed cover yet there are still challenges in retrieving the data collection of shallow water habitats than with other objects on land. Classification algorithms based on remote sensing technology have been developed for application to map benthic habitats, such as Maximum Likelihood, Minimum Distance, and Support Vector Machine. This study focuses on examining those three classification algorithms to retrieve information on the benthic habitat in Pari Island, Jakarta using visual interpretation data for classification, and data field measurements for accuracy testing. This study used five classes of benthic objects, namely sand, sand-seagrass, rubble, seagrass, and coral. The results show how the proposed approach in this study provides an overall good classification of marine habitat with an accuracy produced 63.89–81.95%. The Support Vector Machine algorithm produced the highest accuracy rate of about 81.95%. The Support Vector Machine algorithm at a very high spatial resolution is considered to be capable of identifying, monitoring, and performing the rapid assessment of benthic habitat objects.
17
Sativa, Denianto Yoga, I. Gede Nano Septian i Febrian Kusuma Atmanegara. "Benthic Habitat Mapping Using Sentinel-2A Satellite Imagery in Serewe Bay". Jurnal Biologi Tropis 22, nr 1 (26.12.2021): 55–61. http://dx.doi.org/10.29303/jbt.v22i1.3157.
Pełny tekst źródłaStreszczenie:
Serewe Bay is an important area for sustainable fisheries. This information on benthic habitats is important to know for sustainable management. However, at the moment there is no information on the distribution of benthic habitats in Serewe Bay. The research utilizes Sentinel 2A satellite imagery where the image used is obtained through the earthexplorer.usgs.gov website. Image data will be analyzed through several correction analysis processes, namely reflectance correction, sunglint, and water column or Lyzenga in order to obtain an image display that can be used to identify benthic habitats in Serewe Bay. In addition, a field data survey was also carried out to test the accuracy of the results of processing the Sentinel 2A satellite image of Serewe Bay. Image processing results show that there are 3 categories of benthic habitats, namely Seagrass, Sand and Mixed habitats in which there are macroalgae, dead coral, and coral fractures. The results of the field survey and accuracy calculations show that the accuracy of sentinel 2A image processing in Serewe Bay reaches 63.41% with the dominant benthic distribution consisting of seagrass, mixed benthic habitat and sand. Meanwhile, the calculation of the area of important benthic habitats such as seagrass beds in Serewe Bay can reach 156 Ha.
18
Friedman, S. T., S. A. Price, K. A. Corn, O. Larouche, C. M. Martinez i P. C. Wainwright. "Body shape diversification along the benthic–pelagic axis in marine fishes". Proceedings of the Royal Society B: Biological Sciences 287, nr 1931 (22.07.2020): 20201053. http://dx.doi.org/10.1098/rspb.2020.1053.
Pełny tekst źródłaStreszczenie:
Colonization of novel habitats can result in marked phenotypic responses to the new environment that include changes in body shape and opportunities for further morphological diversification. Fishes have repeatedly transitioned along the benthic–pelagic axis, with varying degrees of association with the substrate. Previous work focusing on individual lineages shows that these transitions are accompanied by highly predictable changes in body form. Here, we generalize expectations drawn from this literature to study the effects of habitat on body shape diversification across 3344 marine teleost fishes. We compare rates and patterns of evolution in eight linear measurements of body shape among fishes that live in pelagic, demersal and benthic habitats. While average body shape differs between habitats, these differences are subtle compared with the high diversity of shapes found within each habitat. Benthic living increases the rate of body shape evolution and has led to numerous lineages evolving extreme body shapes, including both exceptionally wide bodies and highly elongate, eel-like forms. By contrast, we find that benthic living is associated with the slowest diversification of structures associated with feeding. Though we find that habitat can serve as an impetus for predictable trait changes, we also highlight the diversity of responses in marine teleosts to opportunities presented by major habitats.
19
Br Ginting, Devica Natalia, i Anang Dwi Purwanto. "Semi-Automatic Classification Model on Benthic Habitat Using Spot-7 Imagery in Penerusan Bay, Bali". Jurnal Segara 17, nr 3 (21.12.2021): 185. http://dx.doi.org/10.15578/segara.v17i3.9771.
Pełny tekst źródłaStreszczenie:
Benthic habitats are one of the interesting marine resources and its existence must be preserved. Provision of up-to-date benthic habitat information requires a relatively large amount of time and money. The use of remote sensing technology is one of the best solution. This study aims to develop a semi-automatic processing model that is fast, accurate, and with broad spatial coverage. The satellite image data used is the SPOT-7 image acquired on April 11th, 2018. The method used is a supervised classification with a decision tree algorithm. The analysis was carried out using a script developed in the open-source R application. The results showed that the model used was able to accelerate the processing of benthic habitat extracted from the initial process to the classification. The model developed is able to classify habitat classes based on the training sample data provided so that it does not affect the user’s ability to determine the habitat class. The resulting model accuracy is 93.6%. The validation of the resulting classification showed an overall accuracy of 59% and a kappa accuracy of 0.46. It is necessary to carry out further research by increasing quality and quantity of training samples from each object of benthic habitats and developing scripts in order to produce better mapping accuracy.
20
Rahmani, Elvita, I. Wayan Gede Astawa Karang i I. Dewa Nyoman Nurweda Putra. "Pemetaan Habitat Bentik Menggunakan Citra Sentinel-2A dan Unmanned Aerial Vehicle (UAV) di Perairan Pemuteran, Bali". Journal of Marine Research and Technology 5, nr 1 (28.02.2022): 29. http://dx.doi.org/10.24843/jmrt.2022.v05.i01.p06.
Pełny tekst źródłaStreszczenie:
The benthic habitat has a huge ecological and economic role in the sustainability of the coastal environment and is vulnerable to change. The importance of the existence of the benthic habitat requires identification and monitoring of the habitat's existence and status. One of the technologies that can be utilized is remote sensing technology, which is able to provide solutions to the limitations of conventional methods, such as time that is relatively long, costly, and difficult to reach remote and risky areas. Selection of sensing vehicles takes into consideration the needs and desired qualities because the sensors brought in to detect habitats have different abilities. Sentinel-2A imagery is an open-source satellite with a 10 m spatial resolution capability, while the image from Unmanned Aerial Vehicle (UAV) has a high spatial resolution of up to 1 cm per pixsel depending on flight level. The purpose of this study is to identify the degree of accuracy and the scattered conditions of the benthic habitat by the sentinel-2A imagery and the UAV imagery in mapping the benthic habitat in the shallow waters of Pemuteran. The two images for classification use classification based objects and accuracy tests using the confusion matrix method. Based on field observations, five kinds of habitat composition with vast dead corals, dead coral, rubble, biorock, sand, and stone sand are 13.63 ha, 1.45 ha, 0.87 ha, 6.05 ha, and 1.67 ha on the sentinel-2A imagery and 12.86 ha, 1.54 ha, 0.18 ha, 7.32 ha, and 1.76 ha on the UAV imagery. The Sentinel-2a's imagery capability in mapping the benthic habitat is adopted by 73.95%, whereas the UAV imagery is 81.51%. The value of accuracy obtained in the study shows the use of remote sensing data using both imagery can be used for the mapping of habitat benthic.
21
Kruschel, Claudia, i Stewart T. Schultz. "Aggressive Predation Drives Assembly of Adriatic Fish Communities". Diversity 12, nr 4 (30.03.2020): 130. http://dx.doi.org/10.3390/d12040130.
Pełny tekst źródłaStreszczenie:
We performed over 19,000 lure-assisted, underwater visual fish census transects at over 140 shallow coastal sampling locations in the mid- eastern Adriatic sea of the Croatian mainland and islands, recording all fish taxa observed, their predatory behavior in response to the lure, and the cover of benthic habitats with which they were associated. We hypothesized that prey habitat preference was a learned or selected response to aggressive behavior by piscivorous mesopredators, and predicted that mobile prey would be spatially segregated from aggressive predators into different benthic habitats within local sampling sites. We found that aggressive piscivores were primarily wait-chase or cruise-chase mesopredators that preferentially foraged along heterogeneous habitat edges within juxtapositions of rock, unconsolidated sediment, macroalgae (Cystoseira spp.) and seagrass (usually Posidonia oceanica). Prey species and less aggressive piscivores avoided these heterogeneous habitats and preferred more homogeneous habitats that the aggressive predators in turn avoided. We found strong and consistent spatial segregation between aggressive predators on the one hand, and less aggressive predators and prey on the other hand. These results are consistent with the hypothesis that aggressive behavior by piscivorous species is the primary organizing force shaping assembly of fish communities at our study sites, driving preference and occupancy of heterogeneous and homogeneous benthic habitats. Management of shallow benthic resources should recognize the value of complementarity in habitats allowing coexistence of predators and prey through contrasting habitat preferences.
22
Murkin, Henry R., i John A. Kadlec. "Responses by benthic macroinvertebrates to prolonged flooding of marsh habitat". Canadian Journal of Zoology 64, nr 1 (1.01.1986): 65–72. http://dx.doi.org/10.1139/z86-010.
Pełny tekst źródłaStreszczenie:
This study examined the seasonal differences in benthic invertebrate densities and biomass within the dominant vegetation types in a series of 5-ha experimental marshes in south central Manitoba. Following periods of normal water depths, the marshes were flooded to 1 m above the existing cattail beds for up to 2 years to determine the benthic invertebrate response to prolonged above-normal flooding of the marsh habitat. Benthic invertebrate densities and biomass were low during periods of normal water depths when compared with levels later during flooding. The benthic response to flooding was primarily within the herbivore–detritivore group, especially nonpredaceous chironomids. All cover types other than former open-water sites showed increases in benthos densities, biomass, and numbers of taxa following flooding. The increases following flooding appear to be related to the death of the belowground components of the emergent vegetation, the availability of coarse organic litter early in flooding, and the development of fine particulate organic matter during flooding.
23
Bellchambers, Lynda M., Scott N. Evans i Jessica J. Meeuwig. "Abundance and size of western rock lobster (Panulirus cygnus) as a function of benthic habitat: implications for ecosystem-based fisheries management". Marine and Freshwater Research 61, nr 3 (2010): 279. http://dx.doi.org/10.1071/mf09031.
Pełny tekst źródłaStreszczenie:
Ecosystem-based fisheries management (EBFM) requires the expansion of fisheries research programs to include the relationship between target species and their habitats such that trophic and other ecological interactions can be assessed. The western rock lobster (Panulirus cygnus) is an ecologically important species that supports Australia’s most valuable single-species fisheries. We tested the relationship between abundance and size of western rock lobster and benthic habitats based on the annual independent breeding stock survey and benthic towed video transects. The work was undertaken at Dongara, Jurien Bay and Lancelin, Western Australia between 2005 and 2007. Abundance of western rock lobster was significantly but moderately related to benthic habitat (adjR2 = 0.28), with high abundances associated with high cover of mixed assemblage and Ecklonia sp. Size was effectively predicted by habitat (adjR2 = 0.65) with larger lobsters found in mixed assemblages with sponge and smaller lobsters associated with mixed assemblage with Ecklonia sp. Our study has shown that understanding the influence of habitat and fishing pressure on the abundance and size of targeted species is a critical step in the effective implementation of EBFM.
24
Hafizt, Muhammad, Marindah Yulia Iswari i Bayu Prayudha. "Kajian Metode Klasifikasi Citra Landsat-8 untuk Pemetaan Habitat Bentik di Kepulauan Padaido, Papua". Oseanologi dan Limnologi di Indonesia 2, nr 1 (5.05.2017): 1. http://dx.doi.org/10.14203/oldi.2017.v2i1.69.
Pełny tekst źródłaStreszczenie:
<strong>Assessment of Landsat-8 Classification Method for Benthic Habitat Mapping in Padaido Islands, Papua.</strong> Indonesia is the biggest archipelagic country in the world with an area of coral reefs of 39,583 km.This area has to be managed effectively and efficiently utilizing satellite remote sensing technique capable of mapping of benthic habitat coverage, such as coral reefs, seagrasses, macroalgae, and bare substrates. The technique is supported by the availability of Landsat-8 OLI satellite images that have been recording the regions of Indonesia continuously every 16 days. This research was carried out in June 2015 in parts of Padaido Islands, Papua. This area was selected due to high coral reef damages. This study utilized Landsat-8 OLI to compare two classification methods, namely pixel based and object based methods using ‘maximum 2 likelihood’ (ML) and ‘example based feature extraction’ classifications, respectively, after water column correction (Lyzenga method). The results showed that both methods produced benthic habitat maps with 7 class covers. The pixel-based classification resulted in a better overall accuracy (47.57%) in the mapping of benthic habitats than object-based classification approach (36.17%). Thus, the ML classification is applicable for benthic habitat mapping in Padaido Islands. However, the consistency of this method must be analyzed in many diffrent locations of Indonesian waters.
25
Moraes, Karlos, Allan T. Souza, Mojmír Vašek, Daniel Bartoň, Petr Blabolil, Martin Čech, Romulo A. dos Santos i in. "Openness of Fish Habitat Matters: Lake Pelagic Fish Community Starts Very Close to the Shore". Water 13, nr 22 (20.11.2021): 3291. http://dx.doi.org/10.3390/w13223291.
Pełny tekst źródłaStreszczenie:
Fish communities differ significantly between the littoral and the pelagic habitats. This paper attempts to define the shift in communities between the two habitats based on the European standard gillnet catch. We sampled the benthic and pelagic habitats from shore to shore in Lake Most and Římov Reservoir (Czech Republic). The 3 m deep pelagic nets were spanned across the water body at equal distances from two boundary points, where the depth was 3.5 m. The benthic community contained more fish, more species, and smaller individuals. The mild sloped littoral with a soft bottom attracted more fish than the sloping bank with a hard bottom and less benthos and large Daphnia. The catch of the pelagic nets was dominated by eurytopic fish—rudd (Scardinius erythrophthalmus) and roach (Rutilus rutilus) in Most and bleak (Alburnus alburnus) in Římov. With the exception of one case where overgrown macrophytes extended the structured habitat, the largest shift from the benthic to the pelagic community was observed only in the first pelagic gillnet above the bottom depth of 3.5 m. Open water catches were relatively constant with small signs of decline towards the middle of the lake. The results indicate that the benthic gillnet catch is representative of a very limited area and volume, while most of the volume is dominated by the pelagic community. This has important consequences for the assessment of the community parameters of the whole lake following the European standards for gillnet sampling design.
26
Ross, P. M., S. F. Thrush, J. C. Montgomery, J. W. Walker i D. M. Parsons. "Habitat complexity and predation risk determine juvenile snapper (Pagrus auratus) and goatfish (Upeneichthys lineatus) behaviour and distribution". Marine and Freshwater Research 58, nr 12 (2007): 1144. http://dx.doi.org/10.1071/mf07017.
Pełny tekst źródłaStreszczenie:
Early research into the distribution of juvenile snapper (Pagrus auratus) indicated that complex habitats were not important during early life stages. Recent studies in soft-sediment environments, however, have shown juvenile snapper to be more abundant in areas of complex habitat. No previous studies have investigated how and why this species uses both reef and soft-sediment habitats. Therefore, we examined the role of topographic complexity in influencing juvenile snapper distribution and habitat use, providing both field and laboratory evidence for the importance of complex benthic habitats for juvenile snapper and goatfish (Upeneichthys lineatus). Underwater visual censuses showed both species to be most abundant over sand flats adjacent to rocky reef habitats, a distribution that may balance the requirements of food acquisition and predator avoidance. In aquaria experiments, where juvenile snapper were given a choice between habitat with and without shelter, the use of shelter habitat increased significantly in the presence of a predatory threat. This demonstration of the use of complex habitat as shelter highlights the importance of benthic complexity for juvenile snapper and suggests that the management of essential habitats could enhance juvenile survivorship and should have an important role to play in sustainable management of exploited species.
27
Fukunaga, Atsuko, John Burns, Brianna Craig i Randall Kosaki. "Integrating Three-Dimensional Benthic Habitat Characterization Techniques into Ecological Monitoring of Coral Reefs". Journal of Marine Science and Engineering 7, nr 2 (28.01.2019): 27. http://dx.doi.org/10.3390/jmse7020027.
Pełny tekst źródłaStreszczenie:
Long-term ecological monitoring of reef fish populations often requires the simultaneous collection of data on benthic habitats in order to account for the effects of these variables on fish assemblage structure. Here, we described an approach to benthic surveys that uses photogrammetric techniques to facilitate the extraction of quantitative metrics for characterization of benthic habitats from the resulting three-dimensional (3D) reconstruction of coral reefs. Out of 92 sites surveyed in the Northwestern Hawaiian Islands, photographs from 85 sites achieved complete alignment and successfully produced 3D reconstructions and digital elevation models (DEMs). Habitat metrics extracted from the DEMs were generally correlated with one another, with the exception of curvature measures, indicating that complexity and curvature measures should be treated separately when quantifying the habitat structure. Fractal dimension D64, calculated by changing resolutions of the DEMs from 1 cm to 64 cm, had the best correlations with other habitat metrics. Fractal dimension was also less affected by changes in orientations of the models compared to surface complexity or slope. These results showed that fractal dimension can be used as a single measure of complexity for the characterization of coral reef habitats. Further investigations into metrics for 3D characterization of habitats should consider relevant spatial scales and focus on obtaining variables that can complement fractal dimension in the characterization of reef habitats.
28
Dauvin, Jean-Claude, Jean-Philippe Pezy, Emmanuel Poizot, Sophie Lozach i Alain Trentesaux. "A Multidisciplinary Approach for A Better Knowledge of the Benthic Habitat and Community Distribution in the Central and Western English Channel". Journal of Marine Science and Engineering 10, nr 8 (12.08.2022): 1112. http://dx.doi.org/10.3390/jmse10081112.
Pełny tekst źródłaStreszczenie:
About 80% of the seabed of the English Channel (EC) is covered by coarse sediment, from coarse sand to pebbles. Quantitative data on the benthic macrofauna in these types of sediment remains are rare due to the difficulty of using grab corers in such hard substrates. The deepest central part of the EC (45–101 m depth) was prospected during two VIDEOCHARM surveys in June 2010 and June 2011 to increase knowledge of such sublittoral coarse sediment benthic habitats. Sampling focussed on a longitudinal transect in the deepest part of the EC (13 boxes), extending from the western approach to the Greenwich meridian. Both indirect (side scan sonar, Remote Operated Vehicule) and direct (grab sampling with benthos determination, and grain-size analyses) approaches were used and combined, permitting description of the benthic habitats and communities using seven methods. Five benthic EUNIS habitats (European Nature Information System) were reported: MC3215, MD3211, MC4, MC3212 and MC4215, of which two extended main habitats (MC3211 and M23212) corresponded to an eastern/western gradient from sandy gravel to sandy gravel and pebbles sediment. Three other spatially discrete habitats were associated with poor coarse sand and gravel habitats as well as sandy gravel and pebbles with the presence of the brittle star Ophiothrix fragilis. Taxonomic richness of both extended habitats was on the same order of magnitude as the coarse sand habitat reported elsewhere in the EC, whilst the abundances were among the lowest in deeper areas with low nutrient input and low primary production. The epifauna appeared relatively homogenous in this type of sediment at the scale of the sampling area and was not determined to assign a EUNIS habitat/class. ROV footage illustrated the presence of large epifauna and provided valuable information to ground truth in other sampling methods such as side scan sonar mosaic. Grab photos showing surface sediment was relevant to determine the sediment type, whilst granulometric analyses gave additional information on fine particles content (typically very low).
29
Beauchard, O., S. Mestdagh, L. Koop, T. Ysebaert i PMJ Herman. "Benthic synecology in a soft sediment shelf: habitat contrasts and assembly rules of life strategies". Marine Ecology Progress Series 682 (20.01.2022): 31–50. http://dx.doi.org/10.3354/meps13928.
Pełny tekst źródłaStreszczenie:
Biological traits of benthic macroinvertebrates from a large area of the North Sea soft sediments were used to explore habitat occupancy within seascapes of contrasting hydrodynamics. The area, the Dutch sector of the North Sea, is mainly composed of 2 habitats: shallow dynamic bottoms of heterogeneous geomorphologies and deep homogeneous muddy bottoms. Higher within-habitat heterogeneity was hypothesized to more specifically select benthic life strategies according to environmental filtering, i.e. through the action of abiotic forces. Functional community patterns were explored through the RLQ method, which relates habitat and trait variables, at different spatial scales of specific seascape heterogeneity, and functional diversity indices were used to shed light on community assembly mechanisms. Locally, 3 associations between habitat characteristics and biological traits were shown to correspond with predictions of life history theories, whereas only 2 emerged when considering all types of seascapes. This spatial scale-dependence was explained by abiotic alternations masked over the larger scale at which all the existing strategies could not be properly disentangled. The relative composition in strategies obeyed specific assembly rules as identified by functional diversity indices. Seascape geomorphology was locally discriminant of functional patterns, and could account for biodiversification, much beyond basic taxonomic counts. Whereas habitats of higher physical stability hosted the taxonomically richest communities, stress or disturbance frequency increased functional variations within communities due to different strategist habitat occupancies. This study proposes a generic mechanism of benthic community structuring in soft sediment shelves.
30
Shiozawa, Dennis K. "The seasonal community structure and drift of microcrustaceans in Valley Creek, Minnesota". Canadian Journal of Zoology 64, nr 8 (1.08.1986): 1655–64. http://dx.doi.org/10.1139/z86-249.
Pełny tekst źródłaStreszczenie:
Microcrustaceans represent a poorly known component of stream systems. This study examined the seasonal abundance of copepods and cladocerans found in Valley Creek, Washington County, Minnesota. Both benthic densities as well as drift rates were quantified. A total of 16 species was collected in quantitative benthic samples and two additional species occurred in drift samples. The Valley Creek microcrustaceans could be classified into two general groups, those residing in depositional stream habitats similar to a lake or pond littoral and favoring an epibenthic lifestyle, and those found in more erosional habitats where a hyporheic lifestyle is more likely. The microcrustacean community also demonstrated a distinct seasonality with peak abundance in the spring and early summer. Sediment size compositon also demonstrated a seasonal change but detrital composition did not. Microcrustacean drift generally paralleled changes in benthic density but in several cases it tended to lag behind the changes in the benthos. This lag could be due to a seasonal siltation of the sediments, which would compress the habitat volume available to interstitial meiofaunal elements.
31
Bullimore, Ross D., Nicola L. Foster i Kerry L. Howell. "Coral-characterized benthic assemblages of the deep Northeast Atlantic: defining “Coral Gardens” to support future habitat mapping efforts". ICES Journal of Marine Science 70, nr 3 (23.01.2013): 511–22. http://dx.doi.org/10.1093/icesjms/fss195.
Pełny tekst źródłaStreszczenie:
Abstract Bullimore, R. D., Foster, N. L., and Howell, K. L. 2013. Coral-characterized benthic assemblages of the deep Northeast Atlantic: defining “Coral Gardens” to support future habitat mapping efforts – ICES Journal of Marine Science, 70: 511–522. Providing statistically robust maps of habitat distributions on which to base spatial planning and management of the marine area is reliant upon established and agreed descriptions and definitions of habitats. “Coral Gardens” is an Oslo–Paris Convention (OSPAR) listed habitat, which currently cannot be reliably mapped as a result of poorly developed deep-sea habitat classification systems and habitat definitions. The aim of this study is to assess and inform development of the current definition of this habitat to support future mapping efforts. This study uses multivariate community analysis of video data to identify deep-sea benthic assemblages characterized by coral taxa and thus constituting a potential “coral gardens” habitat. Assemblages are assessed against a set of qualifying criteria, derived from current definitions of “coral gardens”, first at the assemblage level then sample by sample. The current definition of “coral gardens” captures a range of benthic assemblages, thus “Coral Gardens” cannot be considered a single “habitat”. While 19 assemblages are identified as being characterized by one or more coral garden taxa, only 8 meet the qualifying criteria. It is suggested that the current definition incorporates descriptions of the different “Coral Gardens” assemblages together with guidance on threshold densities for coral species specific to each assemblage type.
32
Broadbent, HA, SE Grasty, RF Hardy, MM Lamont, KM Hart, C. Lembke, JL Brizzolara i S. Murawski. "West Florida Shelf pipeline serves as sea turtle benthic habitat based on in situ towed camera observations". Aquatic Biology 29 (30.01.2019): 17–31. http://dx.doi.org/10.3354/ab00722.
Pełny tekst źródłaStreszczenie:
The use of marine offshore benthic habitats by sea turtles is poorly characterized due to the difficulty of obtaining in situ data. Understanding benthic habitat use that is important to the species’ reproduction, foraging, and migrations is critical for guiding management decisions. A towed camera-based assessment survey system (C-BASS) equipped with environmental sensors was used to characterize and assess benthic habitats on the West Florida Shelf (WFS) from 2014 to 2018. During these cruises, sea turtles were opportunistically observed during the surveys, and critical in situ data such as spatiotemporal information, species identification, habitat use, behavior, and environmental data were collected and evaluated. In total, 79 sea turtles were observed during 97 transects of approximately 2700 km of seafloor, which was recorded on 380 h of video. Several sea turtle species were spotted within the WFS, including loggerhead Caretta caretta, Kemp’s ridley Lepidochelys kempii, and green turtles Chelonia mydas. These opportunistic sightings revealed an area of high use on the WFS, an anthropogenic structure known as the Gulfstream natural gas pipeline (GSPL). C-BASS survey results suggest that 2 sea turtle species (C. caretta and L. kempii) utilize this artificial structure primarily as a resting area. We emphasize the importance of combining habitat mapping techniques (towed underwater video and multibeam bathymetry/backscatter) with tracking technology to better understand the fine-scale habitat use of sea turtles.
33
Subarno, Tarlan, Vincentius Paulus Siregar i Syamsul Bahri Agus. "OBIA AND BTM INTEGRATION FOR MAPPING HABITAT COMPLEXITY OF CORAL REEFS ON HARAPAN-KELAPA ISLANDS, KEPULAUAN SERIBU". Coastal and Ocean Journal (COJ) 2, nr 1 (10.05.2018): 11–22. http://dx.doi.org/10.29244/coj.2.1.11-22.
Pełny tekst źródłaStreszczenie:
The habitat complexity is indirectly closely related to reef fish abundance. This study aims to map reefs habitat complexity by integrating object-based image analysis (OBIA) and habitat complexity analysis using benthic terrain modeler (BTM). The datasets used were SPOT-7 imagery and water depth derived from satellite imagery. The ground check was conducted to collect field data used as reference for classification and accuracy assessment of classification results. Classification of SPOT-7 imagery was performed using support vector machines (SVM) algorithm, by grouping shallow waters habitats into 4 classes on level 2 and 3 classes on level 3. Accuracy assessment was done by confusion matrix and resulting overall accuracy (OA) 83.55% for level 2 and 79.66% for level 3. The habitat complexity was analyzed using rugosity analysis method (Arc-Chord Ratio) from benthic terrain modeler (BTM) to obtain rugosity index in reefs area. The substrate covers were obtained from OBIA and complexity of habitats were obtained from BTM, then the overlay result shows varying rugosity index on the reef area in Harapan-Kelapa Islands.
Keywords:
coral reefs, OBIA, habitat complexity, rugosity
34
Kim, Taihun, Dae-Won Lee, Han-Jun Kim, Yun-Hwan Jung, Young-Ung Choi, Jung-Hee Oh, Tae-Hoon Kim, Do-Hyung Kang i Heung-Sik Park. "Estimation of the Benthic Habitat Zonation by Photo-Quadrat Image Analysis along the Fringing Reef of Weno Island, Chuuk, Micronesia". Journal of Marine Science and Engineering 10, nr 11 (3.11.2022): 1643. http://dx.doi.org/10.3390/jmse10111643.
Pełny tekst źródłaStreszczenie:
Benthic habitat zonation is described from in situ observations and seabed photographs taken from the coastal area of Weno Island, Chuuk, Micronesia. Habitat groups, types, and boundaries are defined by visible substratum characteristics (i.e., in situ and by digital imaging of photo-quadrats along transect lines), and by cluster and ordination analyses using relative coverage percentage of identified classification categories. The statistical similarity between habitat groups is determined by Analysis of similarity (ANOSIM). Benthic habitat groups with significant influence on the determination of habitat type are isolated by the similarity percentage (SIMPER) test. In addition to the standard practices of using transect lines and collecting data in accordance with the already well-implemented and thoroughly-tested benthic habitat classification scheme for tropical reef monitoring, we applied simple statistics that enable comparative data interpretation. Our simple, repeatable methods provide a framework for benthic habitat-related monitoring research that allows the comparison of results across regions.
35
Hart, Kristen M., David G. Zawada, Autumn R. Sartain i Ikuko Fujisaki. "Breeding loggerhead marine turtles Caretta caretta in Dry Tortugas National Park, USA, show high fidelity to diverse habitats near nesting beaches". Oryx 50, nr 2 (29.12.2014): 283–88. http://dx.doi.org/10.1017/s0030605314000854.
Pełny tekst źródłaStreszczenie:
AbstractWe used satellite telemetry to identify in-water habitat used by individuals in the smallest North-west Atlantic subpopulation of adult nesting loggerhead turtles Caretta caretta during the breeding season. During 2010, 2011 and 2012 breeding periods, a total of 20 adult females used habitats proximal to nesting beaches with various levels of protection within Dry Tortugas National Park. We then used a rapid, high-resolution, digital imaging system to map habitat adjacent to nesting beaches, revealing the diversity and distribution of available benthic cover. Turtle behaviour showing measurable site-fidelity to these diverse habitats has implications for managing protected areas and human activities within them. Protecting diverse benthic areas adjacent to loggerhead turtle nesting beaches here and elsewhere could provide benefits for overall biodiversity conservation.
36
Bissoli, Lorena B., i Angelo F. Bernardino. "Benthic macrofaunal structure and secondary production in tropical estuaries on the Eastern Marine Ecoregion of Brazil". PeerJ 6 (28.02.2018): e4441. http://dx.doi.org/10.7717/peerj.4441.
Pełny tekst źródłaStreszczenie:
Tropical estuaries are highly productive and support diverse benthic assemblages within mangroves and tidal flats habitats. Determining differences and similarities of benthic assemblages within estuarine habitats and between regional ecosystems may provide scientific support for management of those ecosystems. Here we studied three tropical estuaries in the Eastern Marine Ecoregion of Brazil to assess the spatial variability of benthic assemblages from vegetated (mangroves) and unvegetated (tidal flats) habitats. A nested sampling design was used to determine spatial scales of variability in benthic macrofaunal density, biomass and secondary production. Habitat differences in benthic assemblage composition were evident, with mangrove forests being dominated by annelids (Oligochaeta and Capitellidae) whereas peracarid crustaceans were also abundant on tidal flats. Macrofaunal biomass, density and secondary production also differed between habitats and among estuaries. Those differences were related both to the composition of benthic assemblages and to random spatial variability, underscoring the importance of hierarchical sampling in estuarine ecological studies. Given variable levels of human impacts and predicted climate change effects on tropical estuarine assemblages in Eastern Brazil, our data support the use of benthic secondary production to address long-term changes and improved management of estuaries in Eastern Brazil.
37
Abaza, Valeria, Camelia Dumitrache i Adrian Filimon. "The Status of the Sedimentary Benthic Broad Habitats and their Associated Communities in the Romanian Marine Area in 2020". Cercetări Marine - Recherches Marines 51, nr 1 (12.01.2021): 64–79. http://dx.doi.org/10.55268/cm.2021.51.64.
Pełny tekst źródłaStreszczenie:
"The management of marine areas are guided by environmental policies, such as European Union’s Marine Strategy Framework Directive (MSFD), Water Framework Directive (WFD) and Habitats Directive, all requiring periodic assessment and reporting. In 2020, the macrozoobenthos was monitored on the entire Black Sea Romanian shelf at depths ranging between 10 and 100 m. Out of the 43 sampling points of the marine monitoring network, 56 samples were collected in 22 selected stations distributed among broad sedimentary habitat types in Romanian waters in three marine reporting units (variable salinity waters, coastal waters and marine waters). Six types of sedimentary habitats were identified in the above-mentioned marine reporting units according to Marine Strategy Framework Directive (MSFD). Marine Strategy Framework Directive (MSFD) clearly specifies that assessment must take into consideration benthic broad habitat types, including their associated biological communities. To assess the ecological status according to the MSFD of macrozoobenthos from the Romanian shore, M-AMBI*(n) index was used. Following the assessment, the ecological status of the macrozoobenthic communities was determined as good in all three marine reporting units. The data collected in 2020 will contribute to the six-year assessment of the benthic broad habitats and establishment of thresholds for different sub-types. Key-Words: Black Sea, macrozoobenthos, benthic habitat types, M-AMBI *(n) index, environmental status "
38
Schill, Steven R., Valerie Pietsch McNulty, F. Joseph Pollock, Fritjof Lüthje, Jiwei Li, David E. Knapp, Joe D. Kington i in. "Regional High-Resolution Benthic Habitat Data from Planet Dove Imagery for Conservation Decision-Making and Marine Planning". Remote Sensing 13, nr 21 (21.10.2021): 4215. http://dx.doi.org/10.3390/rs13214215.
Pełny tekst źródłaStreszczenie:
High-resolution benthic habitat data fill an important knowledge gap for many areas of the world and are essential for strategic marine conservation planning and implementing effective resource management. Many countries lack the resources and capacity to create these products, which has hindered the development of accurate ecological baselines for assessing protection needs for coastal and marine habitats and monitoring change to guide adaptive management actions. The PlanetScope (PS) Dove Classic SmallSat constellation delivers high-resolution imagery (4 m) and near-daily global coverage that facilitates the compilation of a cloud-free and optimal water column image composite of the Caribbean’s nearshore environment. These data were used to develop a first-of-its-kind regional thirteen-class benthic habitat map to 30 m water depth using an object-based image analysis (OBIA) approach. A total of 203,676 km2 of shallow benthic habitat across the Insular Caribbean was mapped, representing 5% coral reef, 43% seagrass, 15% hardbottom, and 37% other habitats. Results from a combined major class accuracy assessment yielded an overall accuracy of 80% with a standard error of less than 1% yielding a confidence interval of 78–82%. Of the total area mapped, 15% of these habitats (31,311.7 km2) are within a marine protected or managed area. This information provides a baseline of ecological data for developing and executing more strategic conservation actions, including implementing more effective marine spatial plans, prioritizing and improving marine protected area design, monitoring condition and change for post-storm damage assessments, and providing more accurate habitat data for ecosystem service models.
39
Mayer-Pinto, Mariana, Miguel G. Matias i Ross A. Coleman. "The interplay between habitat structure and chemical contaminants on biotic responses of benthic organisms". PeerJ 4 (3.05.2016): e1985. http://dx.doi.org/10.7717/peerj.1985.
Pełny tekst źródłaStreszczenie:
Habitat structure influences the diversity and distribution of organisms, potentially affecting their response to disturbances by either affecting their ‘susceptibility’ or through the provision of resources that can mitigate impacts of disturbances. Chemical disturbances due to contamination are associated with decreases in diversity and functioning of systems and are also likely to increase due to coastal urbanisation. Understanding how habitat structure interacts with contaminants is essential to predict and therefore manage such effects, minimising their consequences to marine systems. Here, we manipulated two structurally different habitats and exposed them to different types of contaminants. The effects of contamination and habitat structure interacted, affecting species richness. More complex experimental habitats were colonized by a greater diversity of organisms than the less complex habitats. These differences disappeared, however, when habitats were exposed to contaminants, suggesting that contaminants can override effects of habitats structure at small spatial scales. These results provide insight into the complex ways that habitat structure and contamination interact and the need to incorporate evidence of biotic responses from individual disturbances to multiple stressors. Such effects need to be taken into account when designing and planning management and conservation strategies to natural systems.
40
van Denderen, P. D., S. G. Bolam, R. Friedland, J. G. Hiddink, K. Norén, A. D. Rijnsdorp, M. Sköld, A. Törnroos, E. A. Virtanen i S. Valanko. "Evaluating impacts of bottom trawling and hypoxia on benthic communities at the local, habitat, and regional scale using a modelling approach". ICES Journal of Marine Science 77, nr 1 (20.11.2019): 278–89. http://dx.doi.org/10.1093/icesjms/fsz219.
Pełny tekst źródłaStreszczenie:
Abstract Bottom trawling disturbance and hypoxia are affecting marine benthic habitats worldwide. We present an approach to predict their effects on benthic communities, and use the approach to estimate the state, the biomass relative to carrying capacity, of the Baltic Sea at the local, habitat, and regional scale. Responses to both pressures are expected to depend on the longevity of fauna, which is predicted from benthic data from 1558 locations. We find that communities in low-salinity regions mostly consist of short-lived species, which are, in our model, more resilient than those of the saline areas. The model predicts that in 14% of the Baltic Sea region benthic biomass is reduced by at least 50%, whereas an additional 8% of the region has reductions of 10–50%. The effects of hypoxia occur over larger spatial scales and lead to a low state of especially deep habitats. The approach is based on a simple characterization of the benthic community, which comes with high uncertainty, but allows for the identification of benthic habitats that are at greatest risk and prioritization of management actions at the regional scale. This information supports the development of sustainable approaches to manage impact of human activities on benthic ecosystems.
41
Kenny, Andrew J., Chris Jenkins, Daniel Wood, Stefan G. Bolam, Peter Mitchell, Callum Scougal i Adrian Judd. "Assessing cumulative human activities, pressures, and impacts on North Sea benthic habitats using a biological traits approach". ICES Journal of Marine Science 75, nr 3 (10.11.2017): 1080–92. http://dx.doi.org/10.1093/icesjms/fsx205.
Pełny tekst źródłaStreszczenie:
Abstract The application of a biological traits analysis, in the present study, has allowed benthic habitat sensitivities and their risk of impact to be mapped at a spatial scale appropriate for the assessment of the North Sea ecoregion. This study considered habitat impacts associated with five important marine sectors; bottom fishing, marine aggregate dredging, sediment disposal, renewable energy devices (tidal, waves, and wind) and the oil and gas sectors, both individually and cumulatively. The significance of the “actual” footprint of impact arising from these human activities and their associated pressures (sediment abrasion, sediment removal, smothering, and placement of hard structures) is presented and discussed. Notable differences in sensitivity to activities are seen depending on habitat type. Some of the more substantial changes in benthic habitat function evaluated are potentially associated with the placement of hard structures in shallow mobile sedimentary habitats, which result in a shift in habitat dominated by small, short-living infaunal species, to a habitat dominated by larger, longer-lived, sessile epibenthic suspension feeders. In contrast, the impacts of bottom fishing, dredging and disposal activities are all assessed to be most severe when executed in deep, sedimentary habitats. Such assessments are important in supporting policies (e.g. spatial planning) directed towards ensuring sustainable “blue-growth,” through a better understanding of the potential ecological impacts associated with human activities operating across different habitat types. The aim of this study is to provide a better understanding of the spatial extent of selected human activities and their impacts on seabed habitats using a biological trait-based sensitivity analysis.
42
Zhang, Yamian, Yi Zhu, Aojie Zuo, Li Wen i Guangchun Lei. "Numerical Response of Migratory Shorebirds to Prey Distribution in a Large Temperate Arid Wetland, China". Scientifica 2016 (2016): 1–9. http://dx.doi.org/10.1155/2016/1297603.
Pełny tekst źródłaStreszczenie:
Wuliangsuhai Lake provides important breeding and stopover habitats for shorebirds. The health of this wetland ecosystem is rapidly deteriorating due to eutrophication and water pollution and environmental management is urgently needed. To explore the connections among ecosystem health, prey density, and shorebird populations, we conducted surveys of both the benthic macroinvertebrates and shorebirds in the shorebird habitat of the wetland during the 2011 autumn migration season. The abundance of both shorebirds and benthic macroinvertebrates varied significantly in both space and time. Our data showed a clear association between shorebird populations and the density of benthic macroinvertebrates, which explained 53.63% of the variation in shorebird abundance. The prey density was strongly affected by environmental factors, including water and sediment quality. Chironomidae were mainly found at sites with higher total phosphorus, but with lower sediment concentrations of Cu. Lymnaeidae were mainly found at sites with a higher pH, lower salinity, and lower concentrations of total phosphorus and Cu. Habitats with very high concentrations of total phosphorus, heavy metals, or salinity were not suitable for benthic macroinvertebrates. Our findings suggest that the reductions of nutrient and heavy metal loadings are crucial in maintaining the ecological function of Wuliangsuhai as a stopover habitat for migratory shorebirds.
43
Tillin, H. M., S. I. Rogers i C. L. J. Frid. "Approaches to classifying benthic habitat quality". Marine Policy 32, nr 3 (maj 2008): 455–64. http://dx.doi.org/10.1016/j.marpol.2007.06.008.
Pełny tekst źródła
44
Mohamed, Hassan, Kazuo Nadaoka i Takashi Nakamura. "Towards Benthic Habitat 3D Mapping Using Machine Learning Algorithms and Structures from Motion Photogrammetry". Remote Sensing 12, nr 1 (1.01.2020): 127. http://dx.doi.org/10.3390/rs12010127.
Pełny tekst źródłaStreszczenie:
The accurate classification and 3D mapping of benthic habitats in coastal ecosystems are vital for developing management strategies for these valuable shallow water environments. However, both automatic and semiautomatic approaches for deriving ecologically significant information from a towed video camera system are quite limited. In the current study, we demonstrate a semiautomated framework for high-resolution benthic habitat classification and 3D mapping using Structure from Motion and Multi View Stereo (SfM-MVS) algorithms and automated machine learning classifiers. The semiautomatic classification of benthic habitats was performed using several attributes extracted automatically from labeled examples by a human annotator using raw towed video camera image data. The Bagging of Features (BOF), Hue Saturation Value (HSV), and Gray Level Co-occurrence Matrix (GLCM) methods were used to extract these attributes from 3000 images. Three machine learning classifiers (k-nearest neighbor (k-NN), support vector machine (SVM), and bagging (BAG)) were trained by using these attributes, and their outputs were assembled by the fuzzy majority voting (FMV) algorithm. The correctly classified benthic habitat images were then geo-referenced using a differential global positioning system (DGPS). Finally, SfM-MVS techniques used the resulting classified geo-referenced images to produce high spatial resolution digital terrain models and orthophoto mosaics for each category. The framework was tested for the identification and 3D mapping of seven habitats in a portion of the Shiraho area in Japan. These seven habitats were corals (Acropora and Porites), blue corals (H. coerulea), brown algae, blue algae, soft sand, hard sediments (pebble, cobble, and boulders), and seagrass. Using the FMV algorithm, we achieved an overall accuracy of 93.5% in the semiautomatic classification of the seven habitats.
45
Chiasson, Wayne B., David LG Noakes i F. William H. Beamish. "Habitat, benthic prey, and distribution of juvenile lake sturgeon (Acipenser fulvescens) in northern Ontario rivers". Canadian Journal of Fisheries and Aquatic Sciences 54, nr 12 (1.12.1997): 2866–71. http://dx.doi.org/10.1139/f97-194.
Pełny tekst źródłaStreszczenie:
The spatial and temporal distribution and relative abundance of juvenile lake sturgeon (Acipenser fulvescens) and benthic macroinvertebrates were examined in the Mattagami and Groundhog rivers, tributaries of the Moose River in northern Ontario, Canada. Relative density and diversity of the benthic fauna were low, the most common taxa being Ablabesmyia sp. (Diptera) and Hexagenia sp. (Ephemeroptera). Benthic organisms were most abundant in substrate dominated by sand and clay. An appreciable portion of the riverbed was strewn with wood chips and was particularly depauperate of macrobenthos. Lake sturgeon foraged exclusively on the benthos, especially taxa of Ephemeroptera, Diptera, and Trichoptera. Hexagenia was the only prey species in greater density in sturgeon stomachs than in the benthos. The largest concentration of juvenile lake sturgeon was found adjacent to substrate dominated by sand and clay. Gillnet catches of lake sturgeon suggest that they are more active at night, which may enhance their foraging success. In these northern rivers, the trophic status of juvenile lake sturgeon is marginalized by an impoverished food supply, in part the consequence of habitat loss resulting from anthropogenic activities.
46
Sudarso, Jojok, Imroatushshoolikhah, Aiman Ibrahim, Siti Aisyah i Laela Sari. "Evaluasi Rehabilitasi Riparian Sungai Ranggeh dengan Indikator Komunitas Makrozoobenthos". Oseanologi dan Limnologi di Indonesia 5, nr 2 (30.08.2020): 105. http://dx.doi.org/10.14203/oldi.2020.v5i2.311.
Pełny tekst źródłaStreszczenie:
<strong>Evaluation of Riparian Rehabilitation in River River Usingthe Macrozoobenthos Community Indicator. </strong>Macrozoobenthos organism is one of aquatic biota which is often used to assess the ecosystems health of river.The evaluation of riparian habitat rehabilitation using benthic macroinvertebrates has been commonly used in many countries. The purposes of this study were to evaluate the impact of Ranggeh river riparian rehabilitation and to determine environmental parameters that influenced benthic macroinvertebrate communities in Ranggeh River. This research was conductedfrom February to September 2019. Benthic macroinvertebrate Benthic macroinvertebrates, river, evaluation, EPT, rehabilitationsamples were collected using Hess Sampler in a sampling area of 0.2 m<sup>2</sup>. This evaluation was carried out after two months since the rehabilitation of riparian habitat completed. The results show that rehabilitation of the riparian habitat has changed the community, in the aspects of biological metrics of taxa number, abundance, and taxa numbersof Ephemeroptera, Plecoptera, and Trichoptera (EPT). Furthermore, the taxa number and EPT metrics increased after habitat rehabilitation, however the abundance decreased slightly. In addition, the taxa number metric was positively correlated with conductivity parameter (r = 0.8), but negatively correlatedto turbidity (r = -0.91) and pH (r = -0.77). Meanwhile, the EPT metric was negatively correlated with turbidity parameters (r = -0.76) and %<em>embeddedness</em> (r = -0.94). The total abundance metric was not sensitive to the parameters measured in this study. Meanwhile, biological metrics for taxa number and EPT can be used to assess rehabilitation success of river ecosystem habitats
47
Mello, H. Lee, Abigail M. Smith i Anna C. L. Wood. "Voluntary fishing restrictions alone do not promote growth of bryozoan-dominated biogenic habitat on the Otago shelf, southeastern New Zealand". ICES Journal of Marine Science 78, nr 4 (1.04.2021): 1542–53. http://dx.doi.org/10.1093/icesjms/fsab056.
Pełny tekst źródłaStreszczenie:
Abstract On the continental shelf, New Zealand bryozoans dominate ecologically-important three-dimensional benthic habitat providing structural complexity which hosts a wide variety of fauna, including economically valuable species (e.g. oysters and blue cod). The association between these species and bryozoan-dominated biogenic habitat commonly results in trawling damage to the benthos; eliminating pressure from destructive fishing practices could support bryozoan regrowth. In 2002, a voluntary fishing restriction was designated over part of one such bryozoan-dominated biogenic habitat, but the efficacy of this ban has not been assessed. Statutory marine protected areas have been proposed in the same area; they aim to achieve bryozoan protection and recovery. A comparison of the bryozoan fauna using benthic images from 2003 and 2019 from the Otago shelf, South Island, New Zealand/Te Waipounamu, Aotearoa shows that a 17-year voluntary fishing ban has been ineffective at increasing the cover and richness of bryozoan-dominated biogenic habitat on the Otago shelf. This study provides a baseline for future monitoring and develops useful metrics for recovery, while calling for further research on the biology and ecology of habitat-forming bryozoans.
48
Giraldo-Ospina, Ana, Gary A. Kendrick i Renae K. Hovey. "Depth moderates loss of marine foundation species after an extreme marine heatwave: could deep temperate reefs act as a refuge?" Proceedings of the Royal Society B: Biological Sciences 287, nr 1928 (10.06.2020): 20200709. http://dx.doi.org/10.1098/rspb.2020.0709.
Pełny tekst źródłaStreszczenie:
Marine heatwaves (MHWs) have been documented around the world, causing widespread mortality of numerous benthic species on shallow reefs (less than 15 m depth). Deeper habitats are hypothesized to be a potential refuge from environmental extremes, though we have little understanding of the response of deeper benthic communities to MHWs. Here, we show how increasing depth moderates the response of seaweed- and coral-dominated benthic communities to an extreme MHW across a subtropical–temperate biogeographical transition zone. Benthic community composition and key habitat-building species were characterized across three depths (15, 25 and 40 m) before and several times after the 2011 Western Australian MHW to assess resistance during and recovery after the heatwave. We found high natural variability in benthic community composition along the biogeographic transition zone and across depths with a clear shift in the composition after the MHW in shallow (15 m) sites but a lot less in deeper communities (40 m). Most importantly, key habitat-building seaweeds such as Ecklonia radiata and Syctothalia dorycarpa which had catastrophic losses on shallow reefs, remained and were less affected in deeper communities. Evidently, deep reefs have the potential to act as a refuge during MHWs for the foundation species of shallow reefs in this region.
49
Têtu, Catherine, Sean Mitchell, Charles MacInnis i Barry R. Taylor. "Restoration of a Nova Scotia stream to enhance Atlantic salmon provides few benefits to benthic invertebrates". Proceedings of the Nova Scotian Institute of Science (NSIS) 48, nr 2 (7.05.2016): 211. http://dx.doi.org/10.15273/pnsis.v48i2.6656.
Pełny tekst źródłaStreszczenie:
Stream restoration is often undertaken with the goal of improving habitat for one focal species, most often a salmonid fish such as trout or salmon. Improvements in channel structure, especially the flushing of silt from sediments, should also benefit benthic invertebrate communities, but studies to date suggest substantial changes in benthic communities following restoration are not common. In a third-order Nova Scotia stream, we examined the effect of successful restoration to improve habitat for spawning Atlantic salmon on benthic invertebrate communities at sites where clogging of the bottom cobble with fine silt had been alleviated. In a long-term comparison of two restored sites and two degraded sites, only six of 24 insect taxa showed increased population density five or seven years after restoration. In a second comparison of a comparatively undisturbed site against a newly restored site and a site restored eight years earlier, only three invertebrate taxa appeared to respond positively and consistently to restoration. In both studies there were no substantial changes in total invertebrate density, taxa richness, Simpson’s diversity index or other community metrics over five years, except for a decline in the EPT/Chironomids ratio in the second study. Ordination of sites by correspondence analysis showed that, in both studies, benthic communities at unrestored control sites and restored sites were clearly different and did not become more similar through time. A long-term restructuring of the benthic community in the entire brook is suggested by the appearance of silt-intolerant shredders (Lepidostoma, Leuctra) among the most abundant members of the benthos in the second study, replacing silt-tolerant collectors (Tricorythodes, Optioservus) that dominated the earlier study. Habitat factors unaffected by in-stream restoration (frequent high discharge, lack of woody debris) limit benthic communities more than substratum quality.
50
Bakirman, T., M. U. Gumusay i I. Tuney. "MAPPING OF THE SEAGRASS COVER ALONG THE MEDITERRANEAN COAST OF TURKEY USING LANDSAT 8 OLI IMAGES". ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B8 (24.06.2016): 1103–5. http://dx.doi.org/10.5194/isprs-archives-xli-b8-1103-2016.
Pełny tekst źródłaStreszczenie:
Benthic habitat is defined as ecological environment where marine animals, plants and other organisms live in. Benthic habitat mapping is defined as plotting the distribution and extent of habitats to create a map with complete coverage of the seabed showing distinct boundaries separating adjacent habitats or the use of spatially continuous environmental data sets to represent and predict biological patterns on the seafloor. Seagrass is an essential endemic marine species that prevents coast erosion and regulates carbon dioxide absorption in both undersea and atmosphere. Fishing, mining, pollution and other human activities cause serious damage to seabed ecosystems and reduce benthic biodiversity. According to the latest studies, only 5–10% of the seafloor is mapped, therefore it is not possible to manage resources effectively, protect ecologically important areas. In this study, it is aimed to map seagrass cover using Landsat 8 OLI images in the northern part of Mediterranean coast of Turkey. After pre-processing (e.g. radiometric, atmospheric, water depth correction) of Landsat images, coverage maps are produced with supervised classification using in-situ data which are underwater photos and videos. Result maps and accuracy assessment are presented and discussed.