Ecoregional and temporal dynamics of dugong habitat use in a complex coral reef lagoon ecosystem

Mobile marine species display complex and nonstationary habitat use patterns that require understanding to design effective management measures. In this study, the spatio-temporal habitat use dynamics of the vulnerable dugong (Dugong dugon) were modelled from 16 satellite-tagged individuals in the coral reef lagoonal ecosystems of New Caledonia, South Pacific. Dugong residence time was calculated along the interpolated tracks (9371 hourly positions) to estimate intensity of use in three contrasting ecoregions, previously identified through hierarchical clustering of lagoon topographic characteristics. Across ecoregions, differences were identified in dugong spatial intensity of use of shallow waters, deeper lagoon waters and the fore-reef shelf outside the barrier reef. Maps of dugong intensity of use were predicted from these ecological relationships and validated with spatial density estimates derived from aerial surveys conducted for population assessment. While high correlation was found between the two datasets, our study extended the spatial patterns of dugong distribution obtained from aerial surveys across the diel cycle, especially in shallow waters preferentially used by dugongs at night/dusk during high tide. This study has important implications for dugong conservation and illustrates the potential benefits of satellite tracking and dynamic habitat use modelling to inform spatial management of elusive and mobile marine mammals.

Conventional and UAV-Based Aerial Surveys for Long-Term Monitoring (1954–2020) of a Highly Active Rock Glacier in Austria

Rock glaciers are creep phenomena of mountain permafrost. Speed-up has been observed on several rock glaciers in recent years and attributed to climate change. Although rare, related long-term studies are nevertheless essential to bring a climate perspective to creep velocity changes. In the present study, we focused on changes both in the surface creep velocity and volume of the Leibnitzkopf rock glacier (Hohe Tauern Range, Austria) in the period 1954–2020. We applied 3D change detection using aerial images of both conventional (12 epochs between 1954 and 2018) and unmanned aerial vehicle (UAV)-based aerial surveys (2 epochs, 2019 and 2020), and combined this with ground and air temperature data. Photogrammetric processing (structure-from-motion, multi-view stereo) of the multi-temporal dataset resulted in high-resolution digital orthophotos/DOPs (5–50 cm spatial resolution) and digital elevation models/DEMs (10–50 cm grid spacing). Georeferencing was supported by five externally triangulated images from 2018, bi-temporal aerial triangulation of the image data relying on stable ground around the rock glacier, measured ground control points (2019 and 2020), and measured camera locations (PPK-GNSS) of the UAV flight in 2020. 2D displacement vectors based on the multi-temporal DOPs and/or DEMs were computed. Accuracy analyses were conducted based on geodetic measurements (2010–2020) and airborne laser scanning data (2009). Our analyses show high multi-annual and inter-annual creep velocity variabilities with maxima between 12 (1974–1981) and 576 cm/year (2019–2020), always detected in the same area of the rock glacier where surface disintegration was first observed in 2018. Our volume change analyses of the entire landform for the period 1954–2018 do not indicate any significant changes. This suggests little permafrost ice melt and/or general low ice content of the rock glacier. Analyses of the temperature data reveal a close relationship between higher temperatures and rock glacier acceleration despite the high probability of low ice content. This suggests that hydrogeological changes play an important role in the rock glacier system. The paper concludes with a summary of technical improvements and recommendations useful for rock glacier monitoring and a general view on the kinematic state of the Leibnitzkopf rock glacier.

Challenges for the computer vision community

Computer vision (CV) is rapidly advancing as a tool to make conservation science more efficient, for example, by accelerating the annotation of images from camera traps and aerial surveys. However, before CV can become a widely used approach, several core technology challenges need to be addressed by the CV community. Taking into consideration several case studies in CV where tremendous progress has been made since the emergence of deep learning, this chapter will introduce core concepts in CV, survey several areas where CV is already contributing to conservation, and outline key challenges for the CV community that will facilitate the adoption of CV in mainstream conservation practice.

THE STUDY OF THE “CETUS” UNMANNED AERIAL VEHICLE FOR TOPOGRAPHIC AERIAL SURVEYING

The work aims to analyze and study the possibilities of using “Cetus” unmanned aerial vehicle (UAV) for performing topographic aerial surveys. The authors developed and tested aircraft-type UAV for topographic aerial photography. The studies were conducted on a specialized landfill, at which there is an appropriate number of situational points whose coordinates are determined with high accuracy. These points were used as both reference and control points. The obtained UAV aerial survey materials were subjected to a phototriangulation process to determine the orientation elements and to analyze, first and foremost, the angular orientation elements. The surveying was carried out on a mountainous territory, where the spatial coordinates of 37 situational points were determined by the method of ground-based GPS survey with an average accuracy of up to 0.05 m. These points were used as reference and control points. Aerial photography was performed in such a way that the scale of the images was as uniform as possible. The design solutions implemented in the Cetus UAV provide all the possibilities to perform aerial surveys of territories in strict compliance with the projected flight parameters. UAV equipment provides the necessary real-time correction of the position of the aerial camera. At the same time the optimum straightness of routes, stability of scales and mutual overlapping of pictures is reached. Regarding the accuracy of obtaining the spatial coordinates of the points of terrain objects, using “Cetus” UAV surveys, plans can even be made on a scale of even 1: 1000. As a result of the creation of the UAV “Cetus”, it became possible to perform the topographic aerial survey of the territories and to create large-scale orthophotos that fully meet the instructions. As a result of testing the “Cetus” UAV, it can be used in production processes when drawing up topographic plans for a large-scale series: 1: 1000 – 1: 5000, which will significantly save the cost of performing topographic work.

Toward a High Spatial Resolution Aerial Monitoring Network for Nature Conservation—How Can Remote Sensing Help Protect Natural Areas?

Aerial surveys have always significantly contributed to the accurate mapping of certain geographical phenomena. Remote sensing opened up new perspectives in nature monitoring with state-of-the-art technical solutions using modern onboard recording equipment. We developed the technical background and the methodology that supports detailed and cost-effective monitoring of a network of natural areas, thereby detecting temporal changes in the spatial pattern of land cover, species, biodiversity, and other natural features. In this article, we share our experiences of the technical background, geometric accuracy and results of comparisons with selected Copernicus Land Monitoring products and an Ecosystem Map based on the testing of our methodology at 25 sites in Hungary. We combined a high-spatial-resolution aerial remote sensing service with field studies to support an efficient nature conservation monitoring network at 25 permanent sites. By analyzing annually (or more frequently) orthophotos taken with a range of 0.5–5 cm spatial resolution and 3D surface models of aerial surveys, it is possible to map the upper canopy of vegetation species. Furthermore, it allows us to accurately follow the changes in the dynamics at the forest edge and upper canopy, or the changes in species’ dominance in meadows. Additionally, spatial data obtained from aerial surveys and field studies can expand the knowledge base of the High-Resolution Aerial Monitoring Network (HRAMN) and support conservation and restoration management. A well-conducted high-resolution survey can reveal the impacts of land interventions and habitat regeneration. By building the HRAMN network, nature conservation could have an up-to-date database that could prompt legal processes, establish protection designation procedures and make environmental habitat management more cost-effective. Landscape protection could also utilize the services of HRAMN in planning and risk reduction interventions through more reliable inputs to environmental models.

The experience of dividing the potential fields of Donbass into background, residual and local components and some results of interpretation

Статья посвящена определению оптимальных процедур обработки и разделения потенциальных полей на фоновую, остаточную и локальную составляющие, а также обсуждению некоторых результатов. Актуальность работы определяется необходимостью разработки геофизической основы для минерагенического анализа системы Донецкого складчатого сооружения. Цель исследования. Выбор оптимальных процедур обработки геофизических данных и разделение потенциальных полей на фоновую, остаточную и локальную составляющие, оценка возможности использования полученных результатов для минерагенического анализа Донецкого складчатого сооружения. Методы исследования. Исходными материалами для исследования послужили результаты аэросъемочных работ в цифровом формате, проведенных в 2011 году компанией «Аэрогеофизика» с использованием современных высокоточных приборов. А для приграничной полосы с Украиной – материалы аналоговых аэрогеофизических съемок, проведенных до 2000 г. Подразделение исходных полей на составляющие компоненты проведено с использованием методов математического преобразования исходных данных с использованием отечественного программного комплекса ГИС Интегро. Оценка информативности преобразования комплекса исходных данных решалась с привлечением технологии статистического зондирования геополей COSCAD 3D, а также технологии решения обратной задачи гравиразведки и магниторазведки. Результаты исследования. Разработана технология, обеспечивающая составление сводных карт потенциальных полей с использованием материалов разновысотных аэросъемок на основе отечественной геоинформационной системы ГИС Интегро. Установлены оптимальные процедуры и осуществлено подразделение исходных магнитного и гравитационного полей на региональную, остаточную и локальную компоненты. При выделении локальнй составляющей аномалий магнитного поля впервые для исследуемого района выделены и прослежены протяженные зоны слабоинтенсивных положительных магнитных аномалий. Установлено, что эти аномалии связаны с разломами, приуроченными к осевым плоскостям линейных антиклиналей и отражают увеличение намагниченности горных пород в связи с гидротермально-метасоматическими преобразованиями. Распространение выявленных ранее золоторудных проявлений в существенной мере контролируется вновь обнаруженными зонами слабоинтенсивных магнитных аномалий. Это позволяет придать высокую значимость выделяемых линейных аномальных зон как критериев для решения задач минерагенического районирования The article is devoted to determining the optimal procedures for processing and dividing potential fields into background, residual, and local components, as well as discussing some of the results. The relevance of the work is determined by the need to develop a geophysical basis for the mineralogical analysis of the Donetsk folded structure system. Aim. To select the optimal procedures for processing geophysical data and to divide potential fields into background, residual and local components, to evaluate the possibility of using the results obtained for mineragenic analysis of the Donetsk folded structure. Methods.The initial materials for the study were the results of aerial surveys in digital format conducted in 2011 by the company "Aerogeofizika" using modern high-precision instruments. And for the border strip with Ukraine – the materials of analog aerogeophysical surveys conducted before 2000. The division of the source fields into components was carried out using the methods of mathematical transformation of the source data using the domestic GIS Integro software package. The evaluation of the informativeness of the transformation of the source data complex was solved using the COSCAD 3D statistical sounding of geofields, as well as the technology for solving the inverse problem of gravity and magnetic exploration. Results. A technology has been developed that provides the compilation of summary maps of potential fields using materials from different-altitude aerial surveys based on the domestic GIS Integro geoinformation system. Optimal procedures were established and the initial magnetic and gravitational fields were divided into regional, residual, and local components. When identifying the local component of magnetic field anomalies, extended zones of low-intensity positive magnetic anomalies were identified and traced for the first time in the study area. It is established that these anomalies are associated with faults confined to the axial planes of linear anticlines and reflect an increase in the magnetization of rocks due to hydrothermal-metasomatic transformations. The spread of previously identified gold-ore manifestations is significantly controlled by newly discovered zones of low-intensity magnetic anomalies. This makes it possible to attach high importance to the identified linear anomalous zones as criteria for solving problems of mineragenic zoning