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1.
J Environ Manage ; 356: 120564, 2024 Apr.
Article En | MEDLINE | ID: mdl-38479283

Robust quantification of vegetative biomass using satellite imagery using one or more forms of machine learning (ML) has hitherto been hindered by the extent and quality of training data. Here, we showcase how ML predictive demonstrably improves when additional training data is used. We collated field datasets of pasture biomass obtained via destructive sampling, 'C-Dax' reflective measurements and rising plate meters (RPM) from ten livestock farms across four States in Australia. Remotely sensed data from the Sentinel-2 constellation was used to retrieve aboveground biomass using a novel machine learning paradigm hereafter termed "SPECTRA-FOR" (Spectral Pasture Estimation using Combined Techniques of Random-forest Algorithm for Features Optimisation and Retrieval). Using this framework, we show that the low temporal resolution of Sentinel-2 in high latitude regions with persistent cloud cover leads to extensive gaps between cloud-free images, hindering model performance and, thus, contemporaneous ability to forecast real-time pasture biomass. By leveraging the spectral consistency between Sentinel-2 and Planet Lab SuperDove to overcome this limitation, we used ten spectral bands of Sentinel-2, four bands of Sentinel-2 as a proxy for pre-2022 SuperDove (referred to as synthetic SuperDove or SSD), and the actual SuperDove (ASD), given that SuperDove imagery has a higher resolution and more frequent passage compared with Sentinel-2. Using their respective bands as input features to SPECRA-FOR, model performance for the ten bands of Sentinel-2 were R2 = 0.87, root mean squared error (RMSE) of 439 kg DM/ha and mean absolute error (MAE) of 255 kg DM/ha, while that for SSD increased to an R2 of 0.92, RMSE of 346 kg DM/ha and MAE = 208 kg DM/ha. The study revealed the importance of robust data mining, imagery harmonisation and model validation for accurate real-time modelling of pasture biomass with ML.


Machine Learning , Satellite Imagery , Satellite Imagery/methods , Biomass , Farms , Australia
2.
Mar Pollut Bull ; 198: 115818, 2024 Jan.
Article En | MEDLINE | ID: mdl-38000263

Floating marine debris (FMD) is one of the world's most concerning issues due to its potential impact on biodiversity, communities, and ecosystem services. FMD transport and concentrations are driven by fronts, generated by oceanographic processes, and the accumulation of FMD has been reported in gyres, eddies, tidal fronts, salinity fronts, and coastal fronts. This study explores the relationship between fronts and FMD accumulation in the Gulf of Maine (GoM) and the surrounding coastal areas (USA). Frontal edge detection algorithms were applied to sea surface temperature (SST) imagery from the Moderate-resolution Imaging Spectroradiometer (MODIS) between 2002 and 2012. Frontal location is spatially correlated with FMD concentrations collected by the Sea Education Association. Higher concentrations of FMD are associated with frontal frequencies (FF) of 5-10 %. FMD is trapped between fronts and the coastline in accumulation zones. These results highlight the need to consider coastal FMD hotspots, given these are areas of high biodiversity value.


Biodiversity , Ecosystem , Temperature , Satellite Imagery , Salinity , Plastics , Environmental Monitoring/methods , Waste Products/analysis
3.
Alcohol Clin Exp Res (Hoboken) ; 47(8): 1570-1581, 2023 Aug.
Article En | MEDLINE | ID: mdl-37578682

BACKGROUND: High-resolution ecological momentary assessment (HR-EMA) can assess acute alcohol responses during naturalistic heavy drinking episodes. The goal of this study was to use HR-EMA to examine drinking behavior and subjective responses to alcohol in risky drinkers (moderate-severe alcohol use disorder [MS-AUD], heavy social drinkers [HD]) and light drinkers (LD). We expected that risky drinkers would endorse greater alcohol stimulation and reward, with lower sedation, than LD, even when controlling for amount of alcohol consumed. METHODS: Participants (N = 112; 54% male, M ± SD age = 27.2 ± 4.2 years) completed smartphone-based HR-EMA during one typical alcohol drinking occasion and one non-alcohol-drinking occasion in their natural environment. Participants were prompted to complete next-day surveys that assessed drinking-related outcomes, study acceptability, and safety. RESULTS: HR-EMA prompt completion rates were excellent (92% and 89% for the alcohol and nonalcohol episodes, respectively). The MS-AUD group consumed the most alcohol with the highest estimated blood alcohol concentration (eBAC) by the end of the alcohol drinking episode (0.14 g/dL) versus LD (0.02 g/dL), with HD intermediate (0.10 g/dL). Relative to LD, MS-AUD and HD endorsed greater positive effects of alcohol (stimulation, liking, and wanting). CONCLUSIONS: This study is the first to use HR-EMA to measure and compare real-world acute alcohol responses across diverse drinker subgroups, including persons with MS-AUD. Results demonstrate that risky drinkers experience heightened pleasurable effects measured in real-time during natural-environment alcohol responses. Rather than drinking excessively to eventually achieve desirable subjective effects, risky drinkers show sensitivity to positive alcohol effects throughout a heavy drinking episode.

4.
Mar Pollut Bull ; 191: 114929, 2023 Jun.
Article En | MEDLINE | ID: mdl-37075560

To mitigate marine debris and promote sustainable marine industries, legislation and regulations surrounding the management of marine debris have been adopted worldwide. One of the most well-known and important agreements is the International Convention for the Prevention of Pollution from Ships (MARPOL), which focuses on reducing all types of ship-sourced marine pollution. MARPOL Annex V, which deals with the disposal of solid waste, came into force on 31 December 1988. However, was only amended to include a complete ban on waste disposal as of 1 January 2013. Assessing the effectiveness of key regulations is fundamental for supporting evidence-based decisions regarding the management of our oceans. Here, we evaluated whether MARPOL Annex V translated into a decrease in the incidence of shipping- and commercial fishing-sourced debris on remote beaches in Australia using 14 years of standardised, community-driven data. From 2006 to 2020 there was a significant change over time in the density of fishing and shipping debris on Australian beaches; debris density increased up to 2013 followed by a decrease until mid-2017. Although the new regulation started in January 2013, the decrease in density was not recorded until one year later. The decline was only observed for 4 years, reinforcing the existence of lags between the implementation of international agreements and the corresponding potential reduction in debris in the environment. This provides compelling evidence that international agreements and policies by themselves are not enough to solve the debris problem, with improved implementation and enforcement also required. We discuss future perspectives and solutions to reduce ocean-sourced litter inputs into the ocean and highlight the urgent need for action.


Environmental Monitoring , Plastics , Australia , Bathing Beaches , Environmental Pollution , Waste Products , Water Pollution
5.
Psychol Addict Behav ; 37(2): 258-266, 2023 Mar.
Article En | MEDLINE | ID: mdl-36326673

OBJECTIVE: Subjective responses to alcohol play a key role in the development and maintenance of risky drinking and alcohol use disorder (AUD). The social and environmental context where drinking occurs may moderate alcohol's subjective effects, but ecologically valid studies of these associations are limited. The present study used high-resolution ecological momentary assessment (HR-EMA) targeting real-world binge drinking episodes to examine associations among drinking context, alcohol consumption, and subjective responses to alcohol. METHOD: Young adult heavy drinkers (N = 61; 57% male) completed two smartphone-based, 3-hr HR-EMA of drinking context (social context and location), alcohol use, and subjective responses (alcohol stimulation, sedation, feeling, liking, and wanting more). Analyses examined the associations between drinking context and subjective alcohol responses, accounting for demographic characteristics and individual differences in alcohol consumption. RESULTS: Most (85%) participants reported binge drinking during real-world drinking events. Estimated blood alcohol concentration (eBAC) and alcohol stimulation and reward (liking, wanting) were greater when participants drank with others (vs. alone) and in a bar/restaurant (vs. other location). Sedation was higher when drinking alone versus with others. CONCLUSIONS: The present study extends prior laboratory-based research and shows that subjective responses during naturalistic binge drinking episodes may be influenced by drinking context. Drinking with others and in bars and restaurants may increase alcohol consumption, enhance alcohol's rewarding effects, and lead to more alcohol-related harm in at-risk drinkers. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Binge Drinking , Blood Alcohol Content , Young Adult , Humans , Male , Female , Binge Drinking/epidemiology , Ecological Momentary Assessment , Ethanol , Alcohol Drinking
6.
Dev Change ; 50(2): 426-444, 2019 Mar.
Article En | MEDLINE | ID: mdl-31007272

This article challenges Horner and Hulme's call to move from 'international development' to 'global development' with a reaffirmation of the classical traditions of development studies. With some adaptation to fit the changing contemporary context, these traditions not only remain relevant but also recover vital insights that have been obscured in the various fashionable re-imaginings of development. In particular, development thinking and agendas in the past were much more radical and ambitious in addressing the imperatives of redistribution and progressive forms of transformation in the context of stark asymmetries of wealth and power. Such ambition is still needed to address the nature and scale of challenges that continue to face the bulk of countries in the world, particularly given the persistence if not deepening of asymmetries. This reaffirmation is elaborated by addressing three major weaknesses in Horner and Hulme's arguments. First, they do not actually define development, but instead treat it as simply poverty and inequality dynamics, which are better understood as outcomes rather than causes. Second, despite their assertion that the study of (international) development was primarily concerned with between-country inequalities, this is not true. Domestic inequality was in fact central to both development theory and policy since the origins of the field. Third, the authors ignore the rise of neoliberalism from the late 1970s onwards and the profound crisis that this caused to development outside of East Asia and perhaps India, which the jargon of 'global' implicitly obfuscates and even condones. Rather, the experiences of East Asia and in particular China arguably vindicate classical approaches in development studies.

7.
World Econ ; 41(12): 3359-3378, 2018 Dec.
Article En | MEDLINE | ID: mdl-30842691

Current debates about the role of external finance in development mostly overlook the insights from early development economics that late industrialisation generates a structural tendency to run trade deficits, thereby exacerbating rather than relieving external foreign exchange constraints. The developmental role of external finance is therefore based on its strategic marginal contribution to relieve such constraints. External debt in particular also allows countries to pursue industrial strategies without reliance on foreign direct investment. These insights are revisited in this paper as a critical input to both mainstream and heterodox contemporary scholarship on debt and development. While the mainstream generally avoids discussion of state-led industrial policy, the heterodox has converged on a view that developing countries should avoid external finance. The contrasting external account histories of South Korea and Brazil are examined to demonstrate the validity of the classic insights and the contemporary fallacies. While the South Korean case speaks much to its geopolitical context, this does not necessarily refute the principle that post-war late development engenders an intensive demand for external finance, which must be met if industrialisation strategies are not to be stymied, as in the case of Brazil, no matter how effectively domestic strategies are conceived and implemented.

8.
Mar Pollut Bull ; 124(1): 51-55, 2017 Nov 15.
Article En | MEDLINE | ID: mdl-28693807

An increasing number of studies highlight the risk of plastic pollution in the marine environment. However, systematic longitudinal data on the distribution and abundance of plastic debris remain sparse. Here we present the results of a two-year study of plastic pollution within the Tasman Sea, contrasted with a further year of data from the same region, in order to document how the density of debris varies across years in this area. Surface net tows were collected between Hobart, Tasmania and Sydney, Australia during the spring of 2013 and 2014 and compared with a subset of data from autumn 2012 from the same region. Substantial inter-annual variation in mean plastic abundance was observed over the three year period, ranging from to 248.04-3711.64pieceskm-2, confirming the need for multiple years of sampling to fully estimate the extent of, and trends in, plastic pollution.


Environmental Monitoring , Plastics/analysis , Waste Products/analysis , Water Pollutants/analysis , Australia , Pacific Ocean , Seasons , Water Pollution/analysis
9.
Sensors (Basel) ; 16(12)2016 Dec 07.
Article En | MEDLINE | ID: mdl-27941596

Ocean color remote sensing significantly contributes to our understanding of phytoplankton distribution and abundance and primary productivity in the Southern Ocean (SO). However, the current SO in situ optical database is still insufficient and unevenly distributed. This limits the ability to produce robust and accurate measurements of satellite-based chlorophyll. Based on data collected on cruises around the Antarctica Peninsula (AP) on January 2014 and 2016, this research intends to enhance our knowledge of SO water and atmospheric optical characteristics and address satellite algorithm deficiency of ocean color products. We collected high resolution in situ water leaving reflectance (±1 nm band resolution), simultaneous in situ chlorophyll-a concentrations and satellite (MODIS and VIIRS) water leaving reflectance. Field samples show that clouds have a great impact on the visible green bands and are difficult to detect because NASA protocols apply the NIR band as a cloud contamination threshold. When compared to global case I water, water around the AP has lower water leaving reflectance and a narrower blue-green band ratio, which explains chlorophyll-a underestimation in high chlorophyll-a regions and overestimation in low chlorophyll-a regions. VIIRS shows higher spatial coverage and detection accuracy than MODIS. After coefficient improvement, VIIRS is able to predict chlorophyll a with 53% accuracy.


Algorithms , Chlorophyll/analysis , Optical Phenomena , Remote Sensing Technology , Water/chemistry , Antarctic Regions , Chlorophyll A , Computer Simulation , Light , Oceans and Seas
10.
J Phycol ; 51(5): 859-71, 2015 Oct.
Article En | MEDLINE | ID: mdl-26986883

Seaweed morphology is often shaped by the hydrodynamic environment. However, exposure to air at low tide represents an additional factor potentially affecting the morphology of intertidal species. Here, we examined the relationships between the morphology of Hormosira banksii, an important intertidal habitat-forming seaweed in southern Australia, and environmental factors across multiple spatial scales around the island of Tasmania, Australia. Tasmania is surrounded by a diverse coastline with differences in wave exposure, tidal parameters, and temperature. We sampled Hormosira from four regions (100s km apart), three sites (10s km apart) within each region, and two zones (meters apart; eulittoral and sublittoral) at each site, and measured multiple morphological variables to test for differences in morphology at those different spatial scales. Thirteen environmental variables reflecting wave exposure, tidal conditions, and temperature for each site were generated to assess the relationship between Hormosira morphology and environmental variation. Morphology varied at all spatial scales examined. Most notably, north coast individuals had a distinct morphology, generally having smaller vesicles and shorter fronds, compared to other regions. Tidal conditions were the main environmental factors separating north coast sites from other sites and tidal regime was identified as the best predictor of morphological differences between regions. In contrast to other studies, we found little evidence that wave exposure was associated with morphological variation. Overall, our study emphasizes the role of tidal conditions, associated with emersion stress during low tide, in affecting the morphology of intertidal seaweeds.

11.
Mar Environ Res ; 99: 106-16, 2014 Aug.
Article En | MEDLINE | ID: mdl-24838080

The transformation of estuaries by human activities continues to alter the biogeochemical balance of the coastal ocean. The disruption of this balance can negatively impact the provision of goods and services, including fisheries, commerce and transportation, recreation and esthetic enjoyment. Here we examine a link, between the Elkhorn Slough and the coastal ocean in Monterey Bay, California (USA) using a novel application of fatty acid and pigment analysis. Fatty acid analysis of filtered water samples showed biologically distinct water types between the Elkhorn Slough plume and the receiving waters of the coastal ocean. A remarkable feature of the biological content of the plume entering the coastal ocean was the abundance of bacteria-specific fatty acids, which correlated well with concentrations of colored dissolved organic matter (CDOM). Pigment analysis showed that plume waters contained higher concentrations of diatoms and cryptophytes, while the coastal ocean waters showed higher relative concentrations of dinoflagellates. Bacteria and cryptophytes can provide a source of labile, energy-rich organic matter that may be locally important as a source of food for pelagic and benthic communities. Surface and depth surveys of the plume show that the biogeochemical constituents of the slough waters are injected into the coastal waters and become entrained in the northward flowing, nearshore current of Monterey Bay. Transport of these materials to the northern portion of the bay can fuel a bloom incubator, which exists in this region. This study shows that fatty acid markers can reveal the biogeochemical interactions between estuaries and the coastal ocean and highlights how man-made changes have the potential to influence coastal ecological change.


Biomarkers/analysis , Diatoms/physiology , Dinoflagellida/physiology , Estuaries , Fresh Water/chemistry , Microbiota/physiology , Water Movements , Analysis of Variance , California , Chromatography, Gas , Chromatography, High Pressure Liquid , Fatty Acids/analysis , Pacific Ocean , Pigments, Biological/analysis , Species Specificity
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