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1.
Sci Rep ; 14(1): 18964, 2024 Aug 16.
Article in English | MEDLINE | ID: mdl-39152170

ABSTRACT

Accurately and quickly estimating the soil organic carbon (SOC) content is crucial in the monitoring of global carbon. Environmental variables play a significant role in improving the accuracy of the SOC content estimation model. This study focuses on modeling methodologies and environmental variables, which significantly influence the SOC content estimation model. The modeling methods used in this research comprise multiple linear regression (MLR), partial least squares regression (PLSR), random forest, and support vector machines (SVM). The analyzed environmental variables include terrain, climate, soil, and vegetation cover factors. The original spectral reflectance (OSR) of Landsat 5 TM images and the spectral reflectivity after the derivative processing were combined with the above environmental variables to estimate SOC content. The results showed that: (1) The SOC content can be efficiently estimated using the OSR of Landsat 5 TM, however, the derived processing method cannot significantly improve the estimation accuracy. (2) Environmental variables can effectively improve the accuracy of SOC content estimation, with climate and soil factors producing the most significant improvements. (3) Machine learning modeling methods provide better estimation accuracy than MLR and PLSR, especially the SVM model which has the highest accuracy. According to our observations, the best estimation model in the study area was the "OSR + SVM" model (R2 = 0.9590, RMSE = 13.9887, MAE = 10.8075), which considered four environmental factors. This study highlights the significance of environmental variables in monitoring SOC content, offering insights for more precise future SOC assessments. It also provides crucial data support for soil health monitoring and sustainable agricultural development in the study area.

2.
Ecol Evol ; 14(7): e70060, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39041022

ABSTRACT

Plant pH is an emerging functional trait that plays important roles in physiological processes and nutrient cycling. However, how root pH varies among plant functional groups (PFGs) and the regulatory factors on a large scale remain unclear. Therefore, we quantified root pH variation of herbaceous plants in four PFGs from 20 sites on the Tibetan Plateau along a 1600 km transect and explored the correlations between root pH and different PFGs, climate and soil conditions. The results showed that the root pH of herbaceous plants was slightly acidic (6.46 ± 0.05). Grasses had the highest root pH (6.91 ± 0.10) across all functional groups (p < .05), whereas legumes had the lowest (5.90 ± 0.08; p < .05). The root pH decreased with mean annual precipitation, aridity index, soil water content and soil stress coefficient, whereas the significant positive correlation with soil pH. PFGs, climate and soil explained 5.39, 11.15 and 24.94% of the root pH variance, respectively. This study provided a comprehensive analysis of root pH patterns in herbaceous plants over a large spatial scale. Root pH was controlled by the combined influence of PFGs, climate and soil properties, with moisture status being the main influential factor. In contrast to the leaf pH, the root pH of herbaceous plants is strongly affected by the soil pH along environmental gradients. Our findings provide new insights into root functional traits and survival strategies of herbaceous plants in alpine ecosystems.

3.
Sci Total Environ ; 945: 174142, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-38906299

ABSTRACT

Antimicrobial resistance (AMR) poses a severe global health threat, yet the transmission pathways of AMR within communal public environments, where humans and animals interact, remain poorly explored. This study investigated AMR risk pathways, prevalence, and seasonality of extended-spectrum ß-lactamase (ESBL) producing E. coli and K. pneumoniae, and observed practices contributing to environmental contamination within urban, peri-urban, and rural Malawi. Using the SaniPath tool, in August 2020, transect walks across three Malawian study sites identified potential AMR exposure pathways, including drains, standing water, soil, and areas of communal hand contact. Subsequently, from September-2020 to August-2021, 1440 environmental samples were collected at critical points along exposure routes (n = 40/month from each site). These underwent microbiological analysis using chromogenic agar techniques to detect the presence of ESBL E. coli and ESBL K. pneumoniae. Results showed the highest ESBL prevalence in urban environments (68.1 %, 95%CI = 0.64-0.72, p < 0.001) with a higher ESBL presence seen in drains (58.8 %, 95%CI = 055-0.62, p < 0.001) and soil (54.1 %, 95%CI = 0.46-0.62, p < 0.001) compared to other pathways. Environmental contamination was attributed to unavailability and poor condition of sanitation and hygiene infrastructure based on key informant interviews with community leaders (n = 9) and confirmed by independent observation. ESBL prevalence varied between seasons (χ2 (2,N = 1440) = 10.89, p = 0.004), with the highest in the hot-dry period (55.8 % (n = 201)). Prevalence also increased with increased rainfall (for ESBL E.coli). We highlight that community environments are likely to be a crucial component in AMR transmission, evident in the abundance of ESBL bacteria in identified exposure pathways. Additionally, poor sanitation infrastructure and practices coupled with seasonal dynamics further affect the presence of ESBLs in communal environments. Therefore, a context appropriate whole system approach that tackles infrastructure and behavioural factors, supported by effective surveillance is required to impact AMR and a range of aligned development challenges in these settings.


Subject(s)
Environmental Exposure , Escherichia coli , Malawi/epidemiology , Escherichia coli/drug effects , Environmental Exposure/statistics & numerical data , Drug Resistance, Bacterial , Humans , Klebsiella pneumoniae/drug effects , Soil Microbiology , Anti-Bacterial Agents , Environmental Monitoring/methods , beta-Lactamases
4.
Pak J Biol Sci ; 26(4): 193-202, 2023 Mar.
Article in English | MEDLINE | ID: mdl-37779334

ABSTRACT

<b>Background and Objective:</b> Coral reefs on Samalona Island have been under pressure both by natural events and by human (anthropogenic) activities, which have caused area degradation. Research on changes in the area of coral reefs is urgently needed. Hence, the objective of this research was to determine changes in the area of coral reefs from 2017, 2020 and 2023 and to determine the percentage of coral reef cover on Samalona Island. <b>Materials and Methods:</b> The method used to determine changes in the area of coral reef is the (unsupervised) method using Sentinel 2-A imagery and processed with ArcMap 10.8 while determining the percentage of coral reef cover (UPT) and processing with CPCe software. <b>Results:</b> From the results of image processing, it was found that changes occur every 3 years, namely 0.22 Ha, while the results of the accuracy test from the results of image interpretation with a ground check were 87.44%. The results of the percentage of coral reef cover obtained at station I, amounted to 6.99%, at station II 20.55% and at station III, 29.39%. The percentage of coral reef cover on Samalona Island in poor condition refers to the Decree of the Minister of State for the Environment No. 4 of 2001 concerning standard criteria for damage to coral reefs. <b>Conclusion:</b> There is a change in the area of coral reefs on Samalona Island which is heading to a damaged or declining condition every three years from 2017, 2020 to 2023.


Subject(s)
Anthozoa , Coral Reefs , Animals , Humans , Indonesia
5.
Pak J Biol Sci ; 26(5): 266-278, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37859557

ABSTRACT

<b>Background and Objective:</b> Barugaiya Village is one of the villages located in Selayar Islands Regency, South Sulawesi, which has seagrass beds that are spread almost evenly in its waters. Environmental changes are in the form of declining water quality and damage to coastal ecosystems, one of which is seagrass. Therefore, it is necessary to observe changes in the area of seagrass beds in the waters of Barugaiya Village so that it is known how much seagrass has actually been in the area in the last 5 years. <b>Materials and Methods:</b> Observations were made from March to May, 2023 in the waters of Barugaiya Village, Selayar Islands Regency, South Sulawesi. The method used is seagrass classification using Sentinel-2A images corrected by the water column with the Lyzenga algorithm to reduce the effect of depth. <b>Results:</b> The distribution area of seagrass in Barugaiya Village for the 2019-2023 period was 111.03, 107.16, 103.81, 102.54 and 99.70 ha, respectively. Every year there is a decrease in seagrass area, the rate of decline is around 0.02% each year (1.27-3.87 ha). The change in area over the past 5 years has decreased by 0.11% (11.33 ha). <b>Conclusion:</b> Therefore, long-term monitoring of seagrass beds in the waters of Barugaiya Village which are experiencing a decline is needed so that effective management strategies can be identified.


Subject(s)
Ecosystem , Water Quality , Indonesia , Algorithms
6.
Sci Total Environ ; 905: 167102, 2023 Dec 20.
Article in English | MEDLINE | ID: mdl-37717759

ABSTRACT

Lake Erie is the most at risk of the Great Lakes for degraded water quality due to non-point source pollution caused by agricultural activities in the lake's watershed. The extent and temporal patterns of nutrient loading from these agricultural activities is influenced by the timing of agronomic events, precipitation events, and water flow through areas of natural filtration within the watershed. Downstream impacts of these nutrient loading events may be moderated by the co-loading of functionally relevant biogeochemical cycling microbial communities from agricultural soils. This study quantified loading patterns of these communities from tile drain sources, assessed whether functional communities from agricultural sources influenced downstream microbial functionality, and investigated how distance from agricultural sources, storm events, and areas of natural filtration altered nutrient cycling and nutrient fluxes in aquatic and sediment environments. Water and sediment samples were collected in the Wigle Creek watershed in Ontario, from tile drains through to Lake Erie, from May to November 2021, and microbial nitrogen (N) and phosphorous (P) cycling capacity (quantitative PCR), and nutrient levels were evaluated. Results showed that N and P functional groups were co-loaded with nutrients, with increased loading occurring during storm events and during agricultural activities including fertilization and harvest. Overall functional capacity in the aquatic environment decreased with distance from the agricultural sources and as water transited through natural filtration areas. In contrast, the sediment environment was more resilient to both agricultural disturbances and abiotic factors. This study expands our understanding of when and where different stages of N and P cycling occurs in agriculturally impacted watersheds, and identifies both seasons and regions to target with nutrient mitigation strategies.


Subject(s)
Lakes , Water Quality , Agriculture , Phosphorus/analysis , Soil , Nitrogen/analysis , Environmental Monitoring/methods
7.
PeerJ ; 11: e15850, 2023.
Article in English | MEDLINE | ID: mdl-37750078

ABSTRACT

Visual line transect (VLT) surveys are central to the monitoring and study of marine mammals. However, for cryptic species such as deep diving cetaceans VLT surveys alone suffer from problems of low sample sizes and availability bias where animals below the surface are not available to be detected. The advent of passive acoustic monitoring (PAM) technology offers important opportunities to observe deep diving cetaceans but statistical challenges remain particularly when trying to integrate VLT and PAM data. Herein, we present a general framework to combine these data streams to estimate abundance when both surveys are conducted simultaneously. Secondarily, our approach can also be used to derive an estimate of availability bias. We outline three methods that vary in complexity and data requirements which are (1) a simple distance sampling (DS) method that treats the two datasets independently (DS-DS Method), (2) a fully integrated approach that applies a capture-mark recapture (CMR) analysis to the PAM data (CMR-DS Method) and (3) a hybrid approach that requires only a subset of the PAM CMR data (Hybrid Method). To evaluate their performance, we use simulations based on known diving and vocalizing behavior of sperm whales (Physeter macrocephalus). As a case study, we applied the Hybrid Method to data from a shipboard survey of sperm whales and compared estimates to a VLT only analysis. Simulation results demonstrated that the CMR-DS Method and Hybrid Method reduced bias by >90% for both abundance and availability bias in comparison to the simpler DS -DS Method. Overall, the CMR-DS Method was the least biased and most precise. For the case study, our application of the Hybrid Method to the sperm whale dataset produced estimates of abundance and availability bias that were comparable to estimates from the VLT only analysis but with considerably higher precision. Integrating multiple sources of data is an important goal with clear benefits. As a step towards that goal we have developed a novel framework. Results from this study are promising although challenges still remain. Future work may focus on applying this method to other deep-diving species and comparing the proposed method to other statistical approaches that aim to combine information from multiple data sources.


Subject(s)
Caniformia , Sperm Whale , Animals , Cetacea , Acoustics , Bias
8.
PeerJ ; 11: e15766, 2023.
Article in English | MEDLINE | ID: mdl-37637176

ABSTRACT

The Indonesian island of Sulawesi has a unique geology and geography, which have produced an astoundingly diverse and endemic flora and fauna and a fascinating biogeographic history. Much biodiversity research has focused on the regional endemism in the island's Central Core and on its four peninsulas, but the biodiversity of the island's many upland regions is still poorly understood for most taxa, including amphibians and reptiles. Here, we report the first of several planned full-mountain checklists from a series of herpetological surveys of Sulawesi's mountains conducted by our team. In more than 3 weeks of work on Gunung Galang, a 2,254 m peak west of the city of Tolitoli, Sulawesi Tengah Province, on Sulawesi's Northern Peninsula, we recovered nearly fifty species of reptiles and amphibians, more than a dozen of which are either new to science or known but undescribed. The incompleteness of our sampling suggests that many more species remain to be discovered on and around this mountain.


Subject(s)
Biodiversity , Checklist , Indonesia , Geography , Geology
9.
Heliyon ; 9(7): e18052, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37483771

ABSTRACT

The Asiatic black bear (Ursus thibetanus) is considered one of the largest carnivores inhabiting different territories including coniferous and broad-leaved forests, extending from sea level to the elevation of 4300 m. The Kaghan and Siran Valleys in Pakistan's District Mansehra were the location of the current study. To evaluate the altitudinal distribution and seasonal movement of Asiatic black bears in the region, we used three approaches (sign distribution survey, questionnaire-based survey, and scat collecting). A total of 1858 bear signs were observed during the field survey, the highest number of signs was dig marks (1213) followed by plant uprooting. Dig marks (MER: 7.574) were observed repeatedly in each potential site of both valleys followed by plant uprooting (MER: 1.594). Similarly, the altitudinal distribution of black bears was determined through the frequency of signs concerning elevation (m). Elevation of the study area ranged from 1300 to 3500 m and the most abundant population was recorded at the elevation of 2501-3000 m followed by 2001-2500 m. About 52% of local communities encountered black bears during the summer season in the field followed by Spring (23%.8) and winter (15.3%). Manshi Reserver forest (24.5%) from Kaghan and Panjul Reserve forest (31.6) from Siran Valley are the potential summer migratory spots. Eleven scat samples were collected with a 0.103 encounter rate (ER). Most of the scats (about 70%) were observed within the maize crop field in the summer season at low elevation, while just 30% of the scat was observed in the winter season in the forest.

10.
Foods ; 12(13)2023 Jun 28.
Article in English | MEDLINE | ID: mdl-37444243

ABSTRACT

Food choices that shape human diets and health are influenced by various socio-economic factors. Vietnam struggles to meet many nutrition targets where links between food choice and diet have not been widely explored. This study assesses the food choice motives, based on a 28-item food choice questionnaire (FCQ), and the diet quality of 603 adults in three sites (urban, peri-urban, and rural) in northern Vietnam. We assess diet quality using the Diet Quality Index-Vietnam (DQI-V) which consists of variety, adequacy, moderation, and balance components. Using factor analysis, we grouped FCQ items into five factors: health focus, sensory appeal, mood ethics, convenience, and familiarity. The structural equation modeling indicates that food choice motives significantly impact the DQI-V and its components but in different directions. The results show that sensory appeal has a positive association with the overall DQI-V score, while having a negative impact on the variety component. Findings present a potential trade-off issue for interventions and policies related to food products. Nutrition knowledge is positively associated with all elements of diet quality across all three study sites. Vietnamese agrobiodiversity could be better utilized to increase dietary diversity. Differentiated policies are necessary to address the poor dietary diversity and adequacy in northern Vietnam.

11.
Mar Pollut Bull ; 193: 115056, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37352804

ABSTRACT

Recent studies have demonstrated that plankton can be a key pathway for the uptake and transfer of contaminants entering the marine environment up to top predators. The plankton-contaminant MERITE-HIPPOCAMPE cruise was devoted to quantifying contaminants in water and the whole plankton size range (10 size fractions) at 10 stations along a north-south transect in the western Mediterranean Sea from the French to the Tunisian coasts through the Provençal and Algerian basins. Pumping and filtering devices and net sampling have been used for collecting very high amounts of small particles and planktonic organisms in the chlorophyll maximum layer (CML). The present paper characterizes the zooplankton components for which the contaminant measurements were carried out. At each station, a horizontal towed Hydro-Bios net with a 60 µm mesh-size net was used to discriminate 5 size-fractions from 60 µm to a few mm. For each size-fraction, one part of the sample was used for dry weight measurements and the other one for estimating the contribution to biomass of detritus, phytoplankton, and among zooplankton of the major taxonomic groups based on the imagery tools ZOOSCAN and FLOWCAM. In each zooplankton size fraction, metabolic rates were calculated from the size spectrum to estimate trophic and excretion fluxes flowing through this fraction. These observations were compared to a similar analysis of tows in the upper layer (vertical) and the surface layer (horizontal). The total sampled biomass concentration at the CML was higher than in the water column (COL) and much higher than at the surface (SURF) in most of the stations, but in the CML and COL a substantial contribution was due to detritus mostly concentrated in the smallest size-fractions (60-200 µm and 200-500 µm). Absolute values of zooplankton biomass show neither a clear spatial pattern nor a significant difference between strata. The CML layer was dominated by copepods similarly to COL and SURF, but presented a higher contribution of nauplii and a near absence of appendicularians. At some stations, crustaceans and gelatinous plankton could be important contributors to CML. The zooplankton biomass composition of the two smallest fractions (<500 µm) was dominated by nauplii, small copepods and, occasionally, by small miscellaneous organisms (mostly pteropodes). In contrast, clear differences between stations appeared for the largest fractions (>500 µm) due to large crustaceans, gelatinous organisms, and chaetognaths. These changes in biomass composition according to size fractions suggest a progressive trophic shift from dominant herbivory in the smallest fractions to more contrasted trophic structure (including carnivory) in the largest fractions. The daily carbon demand and the N and P excretion of zooplankton were on average higher at the CML but with no significant difference with COL. The zooplankton grazing represented 2.7 to 22.7 % of the phytoplankton stock per day, whereas its excretion represented a daily N and P recycling compared to dissolved inorganic nitrogen and phosphorus stocks ranging respectively from 0.2 to 19 % and from 0 to 21 %. This information should help in the interpretation of the content of various contaminants in zooplankton fractions.


Subject(s)
Copepoda , Plankton , Animals , Zooplankton , Chlorophyll/analysis , Biomass , Phytoplankton , Water , Food Chain
12.
PeerJ ; 11: e15558, 2023.
Article in English | MEDLINE | ID: mdl-37334130

ABSTRACT

Birds are often obligate to specific habitats which can result in study areas with complex boundaries due to sudden changes in vegetation or other features. This can result in study areas with concave arcs or that include holes of unsuitable habitat such as lakes or agricultural fields. Spatial models used to produce species' distribution and density estimates need to respect such boundaries to make informed decisions for species conservation and management. The soap film smoother is one model for complex study regions which controls the boundary behaviour, ensuring realistic values at the edges of the region. We apply the soap film smoother to account for boundary effects and compare it with thin plate regression spline (TPRS) smooth and design-based conventional distance sampling methods to produce abundance estimates from point-transect distance sampling collected data on Hawai'i 'Akepa Loxops coccineus in the Hakalau Forest Unit of the Big Island National Wildlife Refuge Complex, Hawai'i Island, USA. The soap film smoother predicted zero or near zero densities in the northern part of the domain and two hotspots (in the southern and central parts of the domain). Along the boundary the soap film model predicted relatively high densities where 'Akepa occur in the adjacent forest and near zero elsewhere. The design-based and soap film abundance estimates were nearly identical. The width of the soap film confidence interval was 16.5% and 0.8% wider than the width of the TPRS smooth and design-based confidence intervals, respectively. The peaks in predicted densities along the boundary indicates leakage by the TPRS smooth. We provide a discussion of the statistical methods, biological findings and management implications of applying soap film smoothers to estimate forest bird population status.


Subject(s)
Passeriformes , Soaps , Animals , Ecosystem , Forests , Population Density
13.
Sci Total Environ ; 883: 163677, 2023 Jul 20.
Article in English | MEDLINE | ID: mdl-37105488

ABSTRACT

The largest actively cycling terrestrial carbon pool, soil, has been disturbed during latest centuries by human actions through reduction of woody land cover. Soil organic carbon (SOC) content can reliably be estimated in laboratory conditions, but more cost-efficient and mobile techniques are needed for large-scale monitoring of SOC e.g. in remote areas. We demonstrate the capability of a mobile hyperspectral camera operating in the visible-near infrared wavelength range for practical estimation of soil organic carbon (SOC) and nitrogen content, to support efficient monitoring of soil properties. The 191 soil samples were collected in Taita Taveta County, Kenya representing an altitudinal gradient comprising five typical land use types: agroforestry, cropland, forest, shrubland and sisal estate. The soil samples were imaged using a Specim IQ hyperspectral camera under controlled laboratory conditions, and their carbon and nitrogen content was determined with a combustion analyzer. We use machine learning for estimating SOC and N content based on the spectral images, studying also automatic selection of informative wavelengths and quantification of prediction uncertainty. Five alternative methods were all found to perform well with a cross-validated R2 of approximately 0.8 and an RMSE of one percentage point, demonstrating feasibility of the proposed imaging setup and computational pipeline.

14.
Mol Ecol ; 32(13): 3747-3762, 2023 07.
Article in English | MEDLINE | ID: mdl-37060060

ABSTRACT

The processes governing soil bacteria biogeography are still not fully understood. It remains unknown how the importance of environmental filtering and dispersal differs between bacterial taxonomic and functional biogeography, and whether their importance is scale-dependent. We sampled soils across the Tibet plateau, with distances among plots ranging from 20 m to 1550 km. Taxonomic composition of bacterial community was characterized by 16S amplicon sequencing and functional community composition by qPCR targeting 9 functional groups involved in N dynamics. Factors representing climate, soil and plant community were measured to assess different facets of environmental dissimilarity. Both bacterial taxonomic and functional dissimilarities were more related to abiotic dissimilarity than biotic (vegetation) dissimilarity or distance. Taxonomic dissimilarity was mostly explained by differences in soil pH and mean annual temperature (MAT), while functional dissimilarity was linked to differences in soil N and P availabilities and N:P ratio. Soil pH and MAT remained the main determinants of taxonomic dissimilarity across spatial scales. In contrast, the explanatory variables of N-related functional dissimilarity varied across the scales, with soil moisture and organic matter having the highest role across short distances (<~330 km), and available P, N:P ratio and distance being important over long distances (>~660 km). Our results demonstrate how biodiversity dimension (taxonomic versus functional aspects) and spatial scale influence the factors driving soil bacterial biogeography.


Subject(s)
Soil Microbiology , Soil , Tibet , Soil/chemistry , Bacteria/genetics , Biodiversity , Plants
15.
Environ Monit Assess ; 195(5): 532, 2023 Apr 03.
Article in English | MEDLINE | ID: mdl-37009929

ABSTRACT

Shoreline analysis helps to understand the coastal dynamism for decision-making in coastal management. As there are still doubts in transect-based analysis, this study attempts to understand the influence of transect intervals in shoreline analysis. Shorelines were delineated on high-resolution satellite images in Google Earth Pro for twelve beaches in Sri Lanka under different spatial and temporal scales. Shoreline change statistics were calculated using Digital Shoreline Analysis System in the ArcGIS 10.5.1 software under 50 transect interval scenarios, and influence of the transect interval for shoreline change statistics were interpreted using standard statistical methods. Transect interval error was calculated with respect to the 1 m scenario as this has the best beach representation. Results revealed that there is no any significant difference (p > 0.05) of shoreline change statistics between 1 and 50 m scenarios in each beach. Furthermore, it was found that the error was extremely low up to 10 m scenario and then after it was subject to fluctuate in an unpredictable manner (R2 < 0.5). Overall, the study concludes that the influence of the transect interval is negligible and 10-m transect interval is ideal in shoreline analysis for the highest efficacy in small sandy beaches.


Subject(s)
Environmental Monitoring , Geographic Information Systems , Environmental Monitoring/methods , Software , Sri Lanka
16.
PeerJ ; 11: e14881, 2023.
Article in English | MEDLINE | ID: mdl-36874968

ABSTRACT

Although camera trapping has been effectively used for wildlife monitoring, its application to multihabitat insects (i.e., insects requiring terrestrial and aquatic ecosystems) is limited. Among such insects, perching dragonflies of the genus Sympetrum (darter dragonflies) are agroenvironmental indicators that substantially contribute to agricultural biodiversity. To examine whether custom-developed camera traps for perching dragonflies can be used to assess the relative population density of darter dragonflies, camera trapping, a line-transect survey of mature adult dragonflies, and a line-transect survey of exuviae were conducted for three years in rice paddy fields in Japan. The detection frequency of camera traps in autumn was significantly correlated with the density index of mature adults recorded during the transect surveys in the same season for both Sympetrum infuscatum and other darter species. In analyses of camera-detection frequency in autumn and exuviae in early summer, a significant correlation was observed between the camera-detection frequency of mature adults and the exuviae-density index in the following year for S. infuscatum; however, a similar correlation was not observed for other darter species. These results suggest that terrestrial camera trapping has the potential to be effective for monitoring the relative density of multihabitat users such as S. infuscatum, which shows frequent perching behavior and relatively short-distance dispersal.


Subject(s)
Odonata , Animals , Population Density , Ecosystem , Specific Gravity , Agriculture
17.
Data Brief ; 47: 108984, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36860409

ABSTRACT

We measured the relative abundance of sea turtles using standardized transect surveys conducted during the summer and fall of 2013 in neritic waters surrounding the Mississippi River delta in Louisiana, USA. Data comprise sea turtle locations, observation circumstances, and environmental covariates recorded at the beginning of each transect and at the time of each turtle observation. Turtles were recorded by species and size class, as well as location in the water column and the distance the turtle was from the transect line. Transects were performed on an 8.2 meter vessel with two observers atop a 4.5 meter elevated platform, with vessel speed standardized at ∼15 km/hr. These data are the first to describe relative abundance of sea turtles observed from small vessels in this region. Detection of turtles <45 cm SSCL and data detail are greater than aerial surveys. The data serve to inform resource managers and researchers regarding these protected marine species.

18.
Int Health ; 15(Suppl 1): i6-i17, 2023 03 24.
Article in English | MEDLINE | ID: mdl-36960807

ABSTRACT

BACKGROUND: Participatory research methods promote collaborations between researchers and communities to collectively overcome implementation challenges for sustainable social change. Programmes usually take a top-down approach to addressing such challenges. This study developed and piloted contextualised participatory methods to identify community structures that could improve the equity of medicine administration for neglected tropical diseases (NTDs) in northern and southern Nigeria. METHODS: Participants and researchers conducted transect walks and social mapping to understand which community-based structures could be used to maximise accessibility and acceptability of medicines for NTDs. RESULTS: Using visual participatory methods with a diverse set of stakeholders facilitated the identification of new structures within the community that could be used to improve the equity of medicine distribution and access. Available materials such as sticks, stones and leaves were appropriately used by respondents in the rural areas, which increased meaningful engagement irrespective of their literacy level. Structures identified included Qur'anic schools, football grounds, mechanics shops, shrines, village head's houses and worship centres. Challenges in using these structures for medicine distribution included resistance from school authorities and restrictions to women's access due to traditions and norms, particularly within palaces and mosques. CONCLUSIONS: This article highlights the importance of meaningful community engagement methods and engaging gatekeepers in visual participatory methods. It emphasizes the importance of including divergent views of various population groups in order to ensure that all communities are reached by NTDs programmes.


Subject(s)
Neglected Diseases , Schools , Humans , Female , Nigeria , Neglected Diseases/drug therapy , Neglected Diseases/epidemiology , Social Change
19.
PeerJ ; 11: e15061, 2023.
Article in English | MEDLINE | ID: mdl-36945356

ABSTRACT

Halimeda tuna (J. Ellis & Solander) J.V. Lamouroux is the only Halimeda species found in the Mediterranean Sea, and it is an important habitat former. In the northern Adriatic, H. tuna is among the ten most abundant seaweeds in the upper-infralittoral belt in spring and autumn. The modular thalli consist of serially arranged calcified segments. Calcification is closely related to photosynthesis, which causes alkalinization of the inter-utricular space and triggers aragonite formation. Understanding of the complex patterns of segment shape plasticity in relation to CaCO3content at different depth levels is still incomplete. Geometric morphometrics was used to investigate H. tuna segment shape variation on the depth transect at Cape Madona Nature Monument in the northern Adriatic Sea. The position on the thallus and the CaCO3 content of each studied segment were recorded, allowing slight changes in mineral content to be detected at the microscale of the segments. Our results showed that shape, size, or asymmetry of H. tuna segments were not significantly affected by depth. On the other hand, plants that grew deeper were generally more calcified. The apical and subapical segments contributed to the increase in CaCO3 content at the deeper sites, whereas the basal segments did not. This indicates that reniform or oval segments positioned apically or subapically play a key role in calcification of H. tuna in Mediterranean ecosystems.


Subject(s)
Chlorophyta , Seaweed , Animals , Ecosystem , Calcification, Physiologic , Tuna , Carbonates
20.
Insects ; 14(2)2023 Feb 15.
Article in English | MEDLINE | ID: mdl-36835760

ABSTRACT

Insects are important components of biodiversity and play significant roles in the steppe ecosystem. They are abundant, easy to sample, and sensitive to changing conditions, making them useful indicators of environmental changes. This study aims to describe patterns (α and ß) of insect diversity across two steppe types (a typical steppe and a desert steppe) along the Eastern Eurasian Steppe Transect (EEST), as well as evaluate the effects of environmental variables in determining these patterns and the influence of plant diversity alterations on these effects. To this end, we collected 5244 individual insects and found an n-shaped diversity distribution along the latitudinal gradient and a significant difference in insect communities across the two steppe types. Further, the Mantel test and path analysis indicate that climate and grazing activities combine to influence insect diversity, and these effects are mediated through plant diversity, strongly supporting the role of bottom-up effects in situations of climatic and grazing pattern changes. Moreover, the contribution of plant diversity varied with steppe types and insect functional groups, with greater effects seen in the typical steppe and herbivorous insects. This indicated the importance of protecting species diversity in steppes through managing plant diversity and assessments of local environmental factors such as grazing intensity and temperature.

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