Traditional Survey Methods Research Articles

Evaluating new technology for biodiversity monitoring: Are drone surveys biased?

Drones and machine learning‐based automated detection methods are being used by ecologists to conduct wildlife surveys with increasing frequency. When traditional survey methods have been evaluated, a range of factors have been found to influence detection probabilities, including individual differences among conspecific animals, which can thus introduce biases into survey counts. There has been no such evaluation of drone‐based surveys using automated detection in a natural setting. This is important to establish since any biases in counts made using these methods will need to be accounted for, to provide accurate data and improve decision‐making for threatened species. In this study, a rare opportunity to survey a ground‐truthed, individually marked population of 48 koalas in their natural habitat allowed for direct comparison of the factors impacting detection probability in both ground observation and drone surveys with manual and automated detection. We found that sex and host tree preferences impacted detection in ground surveys and in manual analysis of drone imagery with female koalas likely to be under‐represented, and koalas higher in taller trees detected less frequently when present. Tree species composition of a forest stand also impacted on detections. In contrast, none of these factors impacted on automated detection. This suggests that the combination of drone‐captured imagery and machine learning does not suffer from the same biases that affect conventional ground surveys. This provides further evidence that drones and machine learning are promising tools for gathering reliable detection data to better inform the management of threatened populations.

Digital Terrain Models Generated with Low-Cost UAV Photogrammetry: Methodology and Accuracy

Digital terrain model (DTM) generation is essential to recreating terrain morphology once the external elements are removed. Traditional survey methods are still used to collect accurate geographic data on the land surface. Given the emergence of unmanned aerial vehicles (UAVs) equipped with low-cost digital cameras and better photogrammetric methods for digital mapping, efficient approaches are necessary to allow rapid land surveys with high accuracy. This paper provides a review, complemented with the authors’ experience, regarding the UAV photogrammetric process and field survey parameters for DTM generation using popular commercial photogrammetric software to process images obtained with fixed-wing or multicopter UAVs. We analyzed the quality and accuracy of the DTMs based on four categories: (i) the UAV system (UAV platforms and camera); (ii) flight planning and image acquisition (flight altitude, image overlap, UAV speed, orientation of the flight line, camera configuration, and georeferencing); (iii) photogrammetric DTM generation (software, image alignment, dense point cloud generation, and ground filtering); (iv) geomorphology and land use/cover. For flat terrain, UAV photogrammetry provided a horizontal root mean square error (RMSE) between 1 to 3 × the ground sample distance (GSD) and a vertical RMSE between 1 to 4.5 × GSD, and, for complex topography, a horizontal RMSE between 1 to 7 × GSD and a vertical RMSE between 1.5 to 5 × GSD. Finally, we stress that UAV photogrammetry can provide DTMs with high accuracy when the photogrammetric process variables are optimized.

First detection of critically endangered scalloped hammerhead sharks (Sphyrna lewini) in Guam, Micronesia, in five decades using environmental DNA

Among the hammerhead sharks, scalloped hammerheads (Sphyrna lewini) have undergone the steepest population declines worldwide. Due to their high susceptibility to exploitation, the species is now classified as ‘critically endangered’, the most threatened category listed by the International Union for Conservation of Nature. There is an urgent need for data on the distribution of S. lewini to inform the design and implementation of effective conservation management strategies, and mitigate the risk of global extinction. Environmental DNA (eDNA) is emerging as a powerful method to monitor the geographic distribution, population trends, and habitat usage of rare and endangered species. In comparison to traditional survey methods, eDNA methods offer lower cost, higher detection rates, and are non-invasive. At present, there is no targeted eDNA assay for the detection of S. lewini and existing methods to assess their distribution are either fisheries-dependent, leading to bias, or costly and laborious, leading to impracticality in regions of low or unknown abundance. Here we present an optimised workflow for the detection of S. lewini presence using eDNA methods, and apply these to successfully detect scalloped hammerhead sharks in Guam, of the western Pacific Ocean, where their presence has not been scientifically reported since the 1970s. The detection of S. lewini by eDNA survey methods was achieved from a single-day sampling effort, demonstrating the efficacy of the technique and workflow. If implemented, the eDNA survey methods developed here will enable the rapid generation of information on the distribution of scalloped hammerhead sharks in the western Pacific, and likely globally, and assist in the accurate placement of no-take reserves to best enable the species’ recovery.

Improved detection sensitivity using an optimal eDNA preservation and extraction workflow and its application to threatened sawfishes

Abstract Pressures on coastal ecosystems are increasing and aquatic species that are restricted to these habitats are facing the threat of extinction. However, the true extent of many threatened and rare aquatic species, especially elasmobranchs, remains unclear due to high levels of data deficiency and poor efficacy of traditional survey methods. Sawfishes (Pristidae), a family of shark‐like rays, are among the most threatened and rare elasmobranch species and are difficult to detect in turbid, coastal habitats. Reliable cost‐effective tools to detect these species are urgently needed to increase their conservation potential. Characterization of environmental DNA (eDNA) extracted from water samples has garnered significant appeal for detection of rare and threatened species. To assist conservation and monitoring efforts for sawfishes using eDNA, species‐specific TaqMan quantitative polymerase chain reaction assays were developed and validated to detect 1.25–5 copies of a 12S rRNA gene fragment. Filter samples were collected in Northern Territory, Australia to assess the utility of the developed eDNA assays and compare the efficacy of preservation and extraction workflows for detecting rare species. Dwarf sawfish (Pristis clavata) were detected in three of 20 sites, and there was a significant effect of preservation and extraction workflow on total eDNA yield and subsequent detection success. Longmire's preserved samples extracted using glycogen‐aided precipitation yielded a significantly higher concentration of total eDNA (n = 60; β = 1.27, t(95) = 8.172, P < 0.0001) and yielded positive P. clavata eDNA detections compared to ethanol preserved samples extracted using QIAGEN DNeasy kit, which did not yield any positive detections. The optimized eDNA assays were developed to support monitoring efforts for endangered sawfishes. Importantly, this study demonstrates that choice of preservation and extraction workflow requires careful consideration, especially when detection of rare or threatened species can have important management and conservation outcomes.

Evaluation of a citizen science platform for collecting fisheries data from coastal sea trout anglers

There are often limited data available to support the sustainable management of recreational fisheries. Electronic citizen science platforms (e.g., smartphone applications) offer a cost-effective alternative to traditional survey methods — but these data must be validated. We compared sea trout (Salmo trutta) data from a Danish citizen science platform with three independent traditional surveys: a roving creel survey, an aerial survey, and a recall survey. The comparisons include fisheries data (e.g., catch, release, effort, and fish size structure) and demographic descriptors (e.g., age) that were collected within the same spatial and temporal frame. We found general alignment between recreational sea trout catch and effort data that were provided by citizen scientists, or collected by more traditional survey methods. Our results demonstrate that citizen science data have the potential to supplement traditional surveys, or act as an alternative source of catch and effort data. However, results were from a highly specialized fishery within a limited spatial and temporal frame, so more research is needed to assess their relevance over time and to a broader set of fisheries.

Drone‐based thermal remote sensing provides an effective new tool for monitoring the abundance of roosting fruit bats

AbstractAccurate and precise monitoring of species abundance is essential for determining population trends and responses to environmental change. However, traditional population survey methods can be unreliable and labour‐intensive, which complicates the effective conservation and management of many threatened species. We developed a method of using drone‐acquired thermal orthomosaics to monitor the abundance of grey‐headed flying‐foxes (Pteropus poliocephalus) within tree roosts, an IUCN Red Listed species of bat. We assessed the accuracy and precision of this new method and evaluated the performance of four semi‐automated methods for counting flying‐foxes in thermal orthomosaics, including machine learning and Computer Vision (CV) methods. We found a high concordance between the number of flying‐foxes manually counted in drone‐acquired thermal imagery and the true abundance of flying‐foxes in single roost trees, as obtained from direct on‐ground observation. This indicated that the number of flying‐foxes observed in thermal imagery accurately reflected the true abundance of flying‐foxes. In addition, for thermal orthomosaics of whole roost sites, the number of flying‐foxes manually counted was highly repeatable between the same‐day drone surveys and human counters, indicating that this method produced highly precise abundance estimates independent of the identity/experience of human counters. Finally, the number of flying‐foxes manually counted in drone‐acquired thermal orthomosaics was highly concordant with the counts derived from CV and machine learning‐enabled classification techniques. This indicated that accurate and precise measures of colony abundance can be obtained semi‐automatically, thus greatly reducing the amount of human effort involved for obtaining abundance estimates. Our method is thus valuable for reliably monitoring the abundance of individuals in flying‐fox roosts and will aid in the conservation and management of this globally threatened group of flying‐mammals, as well as other homeothermic arboreal‐roosting species.

The techniques and challenges of GPS surveying for vertical alignments in high-rise buildings

PurposeVertical alignment in high-rise building is a very important aspect. The architects are nowadays interested in improvising untypical complicated morphology in building designs which increase the difficulty in surveying for vertical alignments. Although the GNSS survey techniques are widely applied in constructions, there is a lack of data sources to explicitly expose their applicability in high-rise buildings and the challenges to be considered. This study has been oriented to find out the best suitable GPS survey technique for the vertical alignment in high-rise buildings and the practical challenges to be considered.Design/methodology/approachThe findings have been attained by analyzing the reliable data gained through experts' comments through structured questionnaire survey, case studies and experiments on different GPS survey techniques.FindingsThe findings express that the GPS techniques can be used for vertical alignments in high-rise buildings except for direct setting out for which only RTK GPS can be used. There are some practical challenges to be considered in such GPS applications.Research limitations/implicationsThe findings encourage the research community to further focus on the GNSS survey applications in the constructions of high-rise buildings.Practical implicationsThe research expresses applicability of easier and less time-consumed modern GNSS survey techniques instead of traditional survey methods for expediting building constructions.Social implicationsThe knowledge on such modern rapid survey techniques with accuracy, efficiency and reliability highly affects the process of infrastructure development.Originality/valueThe research presents a useful new knowledge on applying GNSS survey techniques for precise survey requirements in the construction industry and exposes the gateways for further researches and development.

Using culturomics and social media data to characterize wildlife consumption.

Wildlife provides food, medicine, clothing, and other necessities for humans, but overexploitation can disrupt the sustainability of wildlife resources and severely threaten global biodiversity. Understanding the characteristics of consumer behavior is helpful for wildlife managers and policy makers, but the traditional survey methods are laborious and time-consuming. In contrast, culturomics may more efficiently identify the features of wildlife consumption. As a case study of the culturomics approach, we examined tiger bone wine consumption in China based on social media and Baidu search engine data. Tiger bone wine is one of the most purchased tiger products; its consumption is closely related to tiger poaching, which greatly threatens wild tiger survival. We searched a popular social media website for the term "tiger bone wine" and focused on posts that were originally created from 1 January 2012 to 31 December 2018. We filtered and classified posts related to the purchase, sale, or consumption of tiger bone wine and extracted information on providers, consumption motivations, year of production, and place of origin of the tiger bone wines based on the texts and photos of these posts. We found 756 posts related to tiger bone wine consumption, 113 of which mentioned providers of tiger bone wine, including friends (53%), elder relatives (37%), peer relatives (7%), and others (3%). Out of the 756 posts, 266 indicated the motivations of tiger bone wine consumption. Tiger bone wines were consumed as a tonic (34%), medicine (23%), game product (30%), and a symbol of wealth (28%). Some posts indicated ≥2 consumption motivations. These findings were consistent with the search queries from Baidu index. Such information could help develop targeted strategies for tiger conservation. The culturomics approach illustrated by our study is a rapid and cost-efficient way to characterize wildlife consumption.

Meta-analysis shows that environmental DNA outperforms traditional surveys, but warrants better reporting standards.

Decades of environmental DNA (eDNA) method application, spanning a wide variety of taxa and habitats, has advanced our understanding of eDNA and underlined its value as a tool for conservation practitioners. The general consensus is that eDNA methods are more accurate and cost‐effective than traditional survey methods. However, they are formally approved for just a few species globally (e.g., Bighead Carp, Silver Carp, Great Crested Newt). We conducted a meta‐analysis of studies that directly compare eDNA with traditional surveys to evaluate the assertion that eDNA methods are consistently “better.”Environmental DNA publications for multiple species or single macro‐organism detection were identified using the Web of Science, by searching “eDNA” and “environmental DNA” across papers published between 1970 and 2020. The methods used, focal taxa, habitats surveyed, and quantitative and categorical results were collated and analyzed to determine whether and under what circumstances eDNA outperforms traditional surveys.Results show that eDNA methods are cheaper, more sensitive, and detect more species than traditional methods. This is, however, taxa‐dependent, with amphibians having the highest potential for detection by eDNA survey. Perhaps most strikingly, of the 535 papers reviewed just 49 quantified the probability of detection for both eDNA and traditional survey methods and studies were three times more likely to give qualitative statements of performance. Synthesis and applications: The results of this meta‐analysis demonstrate that where there is a direct comparison, eDNA surveys of macro‐organisms are more accurate and efficient than traditional surveys. This conclusion, however, is based on just a fraction of available eDNA papers as most do not offer this granularity. We recommend that conclusions are substantiated with comparable and quantitative data. Where a direct comparison has not been made, we caution against the use of qualitative statements about relative performance. This consistency and rigor will simplify how the eDNA research community tracks methods‐based advances and will also provide greater clarity for conservation practitioners. To this end suggest reporting standards for eDNA studies.

EDNA Detection of Native and Invasive Crayfish Species Allows for Year-Round Monitoring and Large-Scale Screening of Lotic Systems

Effective management of both endangered native and invasive alien crayfishes requires knowledge about distribution, monitoring of existing and early detection of newly established populations. Complementary to traditional survey methods, eDNA sampling has recently emerged as a highly sensitive non-invasive detection method to monitor crayfish populations. To advance the use of eDNA as detection tool for crayfish we used a twofold approach: 1) we designed a novel set of specific eDNA-assays for all native (Austropotamobius torrentium, Austropotamobius pallipes, Astacus astacus) and the most relevant invasive crayfish species (Pacifastacus leniusculus, Faxonius limosus, Faxonius immunis) in Central Europe. To ensure specificity each primer pair was tested in silico, in vitro, and in situ; 2) we assessed the influence of spatio-temporal variables (distance to upstream population, season, stream size) on eDNA detection in seven streams using two different detection methods (qualitative endpoint PCR and quantitative droplet digital PCR, ddPCR). The newly developed eDNA assays successfully detected all crayfish species across different lotic and lentic habitats. eDNA detection rate (endpoint PCR) and eDNA-concentration (ddPCR) were significantly influenced by distance and season. eDNA detection was successful up to 7 km downstream of the source population and across all seasons, although detectability was lowest in winter. eDNA detection rate further decreased with increasing stream size. Finally, eDNA-concentration correlated positively with estimated upstream population size. Overall, we provide near operational eDNA assays for six crayfish species, enabling year-round detection, which represents a clear benefit over conventional methods. Due to its high sensitivity, eDNA detection is also suitable for the targeted search of as-yet unrecorded or newly emerging populations. Using quantitative ddPCR might further allow for a rough estimation of population size, provided that the identified spatio-temporal factors are accounted for. We therefore recommend implementing eDNA-detection as a complementary survey tool, particularly for a large-scale screening of data-deficient catchments or a year-round monitoring.

The composition of fish species shows little seasonal variation in eDNA based survey at urban streams

Biodiversity in the city is becoming important as cities are expanded. Thus, the cost-efficient and accurate methodology for the investigation of biota has been consistently demanded. Environmental DNA (eDNA) is one of the emerging tools to supplement traditional survey methods and improve the efficiency of the survey. Summer (from July to August) is the monsoon period in South Korea, so it is excluded from the survey period because of the unstable aquatic environment, the safety of investigators, and accessibility to study sites. On the other hand, spring and autumn (from March to October), excluding the flooding season, are considered suitable times for the survey. This study compared fish composition and distribution by season in summer and autumn using eDNA to identify the change of fish composition and determine the suitability of the eDNA survey for seasonal fish investigation at urban streams. The number of eDNA reads, fish composition, and their community structures was changed according to the season. The total eDNA read was 2.3 times more in October (1,419,062) than in July (3,202,626). In addition, compared to the summer when 13 families and 33 species were detected, 13 families and 35 species were detected in fall. A total of 13 families and 32 species were detected in common. Three species (Acheilognathus rhombeus, Tachysurus fulvidraco, Pungtungia herzi) more were identified, and one (Hemiculter leucisculus) was not detected in October. The result described that the distribution rate of fish species has changed in the study area. Especially, the appearance of invasive species increased from 14 to 20 sites and the habitat range of invasive species was extended in October than July. However, there was no significant difference in richness and diversity except for abundance among fish community structures. This result revealed that eDNA survey methods can identify changes in the composition and distribution of fish by season. Furthermore, based on the little fluctuation in the species appearing according to the season, the study suggested that eDNA can be used to complement traditional survey methods by conducting fish surveys regardless of the survey period.

A roadmap for integrating eDNA in Australian marine park monitoring

Australia has one of the world’s largest marine park estates. At 3.3 million km2, it spans an area three times larger than Germany, France, and the UK combined. Managing and monitoring such a vast and often remote area is logistically challenging and expensive. Current monitoring of Australian parks is decentralised and depends on traditional survey methods. As a result, real-time data on the state of Australia’s marine parks is incomplete, hampering effective management. Environmental DNA has been suggested as a potential solution to some of these challenges, but practical large-scale applications remain largely lacking in Australia. To overcome this, we are developing a roadmap towards integrating eDNA methods in marine park monitoring. We present an overview of the current state of marine monitoring in Australia marine, identify the aspects of bio-monitoring that eDNA can best contribute to, and suggest pathways towards best practice use of eDNA for resource managers in Australia and globally.

Does building development in Dhaka comply with land use zoning? An analysis using nighttime light and digital building heights

Zoning is an important tool to regulate the use of land and to characterize built form over land, and thus to facilitate urban sustainability. Availability of reliable data is crucial for monitoring land use zoning, which contributes directly to the success of the Sustainable Development Goals (SDGs) in general, and SDG Goal 11 for sustainable cities and communities in particular. However, obtaining this valuable information using traditional survey methods is both costly and time-consuming. Remote sensing technology overcomes these challenges and supports urban policymaking and planning processes. This study unveils a novel approach to developing a cost-effective method for identifying building types using Sentinel-2A, Visible Infrared Imaging Radiometer Suite (VIIRS)–based nighttime light (NTL) data, and TanDEM-X–based Digital Surface Model (DSM) data. A newly developed index for this study, the Normalized Difference Steel Structure Index (NDSSI), is useful for rapidly mapping industrial buildings with steel structures. The implementation status of Dhaka’s existing land use plan was evaluated by analyzing the spatial distribution of different types of building uses. This study classifies residential, commercial, and industrial buildings within Dhaka using building height, and nighttime light emission. The experimental results reveal that about 67% of commercial and 51% of industrial buildings within the Dhaka Metropolitan Area (DMA) do not comply with the land use zoning by the Detailed Area Plan (DAP). It also reveals that approximately 10% of commercial buildings, 9% of industrial buildings, and 6% of residential buildings have encroached upon conservation zones (such as open space, flood-prone zones, water bodies, and proposed areas for future road extension). A major constraint in the study was the low spatial resolution of the nighttime light dataset, which made it difficult to distinguish individual sources of light. Still, the methodological approaches proposed in this study are expected to promote reduced costs and efficacious decision-making in urban transformation and to help achieve SDG 11, especially in developing countries.

Horizontal Calibration of Vessels with UASs

Knowledge of offset vectors from vessel mounted sonars, to systems such as Inertial Measurement Units and Global Navigation Satellite Systems is crucial for accurate ocean mapping applications. Traditional survey methods, such as employing laser scanners or total stations, are used to determine professional vessel offset distances reliably. However, for vessels of opportunity that are collecting volunteer bathymetric data, it is beneficial to consider survey methods that may be less time consuming, less expensive, or which do not involve bringing the vessel into a dry dock. Thus, this article explores two alternative methods that meet this criterion for horizontally calibrating vessels. Unmanned Aircraft Systems (UASs) were used to horizontally calibrate a vessel with both Structure from Motion photogrammetry and aerial lidar while the vessel was moored to a floating dock. Estimates of the horizontal deviations from ground truth, were obtained by comparing the horizontal distances between targets on a vessel, acquired by the UAS methods, to multiple ground truth sources: a survey-grade terrestrial laser scan and fiberglass tape measurements. The investigated methods were able to achieve horizontal deviations on the order of centimeters with the use of Ground Control Points.

Spectral Response of Winter Crops Using Multi-temporal Sentinel-2 MSI Data in Visnagar Taluka, Gujarat State

Developing Countries like India has more than half of the population engaged in fishery, agriculture etc. and agriculture drives the economy of the Nation. Traditional survey methods are tedious and time consuming, however, with advancement in Remote Sensing Technology data for Agriculture monitoring can be obtained at local and regional scale. The present study demonstrates the use of multi-year multi-date Sentinel-2 MSI data for winter crop monitoring in in Visnagar taluka Mahesansa district of Gujarat state. Multi-temporal Sentinel-2 data covering study area for the winter crop period from November-2018 to March-2019 was downloaded from https://earthexplorer.usgs.gov/ .The major objective of this study was to monitor site-specific crop growth in different villages of Visnagar Taluka by generating Normalized Difference Vegetation Index (NDVI) profiles of major winter crops. The spectral behavior of wheat, mustard, Fennel and castor crops during active growth stages was studied. The results indicated that different winter crops can be discriminated using the data during the early growth phases like flag-leaf emergence to flowering stages of these crops. Even it was observed that the spectral response of normal-sown and late-sown wheat crop have quite distinct spectral behavior as compared to other winter crops. In this study, the NDVI profiles of different winter crops indicated that Last week of January to first week of February, when all the winter crops were at grand growth stages of grain filling and grain-milk, pod formation (mustard & castor) stages have similar NDVI values, therefore during this period major winter crops in this region may not be possible to discriminate using single date satellite data.

The Drone Revolution of Shark Science: A Review

Over the past decade, drones have become a popular tool for wildlife management and research. Drones have shown significant value for animals that were often difficult or dangerous to study using traditional survey methods. In the past five years drone technology has become commonplace for shark research with their use above, and more recently, below the water helping to minimise knowledge gaps about these cryptic species. Drones have enhanced our understanding of shark behaviour and are critically important tools, not only due to the importance and conservation of the animals in the ecosystem, but to also help minimise dangerous encounters with humans. To provide some guidance for their future use in relation to sharks, this review provides an overview of how drones are currently used with critical context for shark monitoring. We show how drones have been used to fill knowledge gaps around fundamental shark behaviours or movements, social interactions, and predation across multiple species and scenarios. We further detail the advancement in technology across sensors, automation, and artificial intelligence that are improving our abilities in data collection and analysis and opening opportunities for shark-related beach safety. An investigation of the shark-based research potential for underwater drones (ROV/AUV) is also provided. Finally, this review provides baseline observations that have been pioneered for shark research and recommendations for how drones might be used to enhance our knowledge in the future.

Digital Transformation and New Methods of Sociological Research

Today, digital transformation assists us to search for information on the Internet, to digitize data, to store and broadcast it conveniently; however, digital transformation changes not only the quality of technologies, but also the social reality, the structure of society, the ways of social interactions, the social actor, and research methods. Four breakthrough technologies — cloud computing, big data, artificial intelligence, and the Internet of things — determine the direction of these changes. The question is how sociology may use these technologies for its own purposes. In this paper, the outdated approaches of authorities are considered in relation to the monitoring criteria they use to evaluate their activities. We emphasize the potential to obtain representative data by using traditional survey methods. Nevertheless, changes in the socio-psychological characteristics of respondents actualize the transition from mass surveys to big data analysis and force us to replace directly posed questions with the indirect confirmation of hypotheses. The new technologies open greater opportunities for building correlations, identifying hidden patterns, and making predictions than it was possible till now. Thus, we need scientifically based coherent patterns across individual factors in order not to see cause-and-effect relationships in random matches. Research community has to develop these patterns.
 Keywords: Digital Transformation, Big Data, Cloud Computing, Artificial Intelligence, the methods of sociological research

A herpetological survey of Edith L. Moore Nature Sanctuary

Urban herpetology deals with the interaction of amphibians and reptiles with each other and their environment in an urban setting. As such, well-preserved natural areas within urban environments can be important tools for conservation. Edith L. Moore Nature Sanctuary is an 18-acre wooded sanctuary located west of downtown Houston, Texas and is the headquarters to Houston Audubon Society. This study compared iNaturalist data with results from visual encounter surveys and aquatic funnel traps. Results from these two sources showed 24 species belonging to 12 families and 17 genera of herpetofauna inhabit the property. However, several species common in surrounding areas were absent. Combination of data from community science and traditional survey methods allowed us to better highlight herpetofauna present in the park besides also identifying species that may be of management concern for Edith L. Moore. 

Assess the Distribution of Informal Green Space Using Google Street View in Ichikawa City, Japan

The green space provides many benefits for social, environment and ecological for urban life. There is the need to develop a proper plan to ensure the well-being of residents by use other space as supplemental for urban green space (UGS). Informal green space (IGS) was long use as a solution for shortage of UGS and being used widely in recently years. However, it hardly analyzes and manages IGS efficient by traditional survey method because of its characteristics. Google street view (GSV) is a geospatial platform provided free large ground-based database 3600 photographs along streets that available on web interface. It is high possibility to use GSV in assess the distribution of IGS for managing and planning urban greenery and master plan. Ichikawa city, Chiba, Japan covers 57.45 km² while provides about 7.28m² green space area per capita, far from meet the requirement 10m². By choosing this city, the field survey result of previous research could be used to compare to evaluate the accuracy of the remote sensing method. GSV images are downloaded by Street View Download 360 from the network of interval point along the road to detect IGS. After considering the time to acquire GSV and other factors, the 78 meters distance is chosen. The DeepLab V3+ is employed as a semantic segmentation tool and be trained to classify and labeled objects in pictures then separate IGS to surround environment. The map of IGS distribution will be produced from the output data of DeepLab V3+ by using ArcGIS. The final map will be compared with the data of IGS distribution that were recorded in the research of northern part of Ichikawa in 2020 to evaluate the efficiency of this method.

Interannual variability in acoustic detection of blue and fin whale calls in the Northeast Atlantic High Arctic between 2008 and 2018

Northern Hemisphere blue and fin whales are regular summer migrants to Arctic waters. Given the profound changes the Arctic is currently undergoing due to global warming, changes in habitat use and distribution of these migratory species are predicted. In this study, 3 passive acoustic recorders, 2 in Fram Strait about 95 km apart and 1 north of the Svalbard Archipelago (Atwain), were used to investigate the spatial and temporal vocal occurrence of these species in the Northeast Atlantic High Arctic. Acoustic data were available for 7 years for western Fram Strait (WFS), 2.5 years for central Fram Strait (CFS) and 3 years for Atwain. At both Fram Strait locations, most blue whale call detections occurred from August through October, though recently (2015-2018) in WFS a clear increase in blue whale call rates was detected in June/July, suggesting an expansion of the seasonal occurrence of blue whales. In WFS, fin whale calls were detected intermittently, at low levels, almost year-round. In CFS, fin whale calls were more frequent but occurred mainly from July through December. At Atwain, blue whale detections commenced in July, both species were recorded in September/October and fin whale calls extended into November. Results from this study provide novel long-term baseline information about the occurrence of blue and fin whales at extreme northerly locations, where traditional ship-based survey methods are seasonally limited. Continued sampling will support investigation of how environmental change influences cetacean distribution and habitat use.