World's Waters Research Articles

Driving green purchasing: how knowledge and consciousness shape attitudes and intentions to use plastic bottles in East Java

As a country contributing 1.4 tons of plastic waste to the world's waters, Indonesia requires a mature green concept implementation from various stakeholders. However, it is regrettable that no FMCG company has a comprehensive strategy to commit to switching from single-use plastics. This concept enables companies to play in an underutilized niche market. This study fills the knowledge gap by investigating the complex relationship between environmental knowledge, environmental concern, consumer attitudes, and purchase intentions for plastic-bottled beverages. Data were obtained through an online questionnaire distributed to 297 respondents in the East Java. Data were processed using path analysis, revealing that environmental knowledge and concern, as well as consumer attitudes, have a positive and significant relationship with green purchase intention. Environmental knowledge and concern also positively and significantly affect consumer attitudes. Moreover, positive consumer attitudes can reduce the influence of environmental knowledge and concern on purchasing environmentally friendly products. This confirms that positive consumer attitudes towards environmentally friendly products are not the only factor influencing their purchase intentions.

A standard lexicon of terms for area-based conservation version 1.0.

Target 3 in the Kunming-Montreal Global Biodiversity Framework (GBF) calls for protecting at least 30% of the world's lands and waters in area-based conservation approaches by 2030. This ambitious 30×30 target has spurred great interest among policy makers, practitioners, and researchers in defining and measuring the effectiveness of these types of approaches. But along with this broad interest, there has also been a proliferation of terms and their accompanying abbreviations used to describe different types of conservation areas and their governance, planning, management, and monitoring. The lack of standard terms is hindering the use and assessment of area-based approaches to conserve the world's biodiversity. It is difficult to track progress toward GBF Target 3 or to share learning with other practitioners if different groups of people are using different words to describe the same concept or similar words to talk about different concepts. To address this problem, the International Union for Conservation of Nature's World Commission on Protected Areas commissioned a task force to review existing terms and recommend a standard English-language lexicon for this field based on key criteria. The results were definitions of 37 terms across 6 categories, including types of protected and additional conservation areas (e.g., protected area, additional conservation area), sets of these areas (protected area network, protected area system), their governance and management (governance, rightsholders), assessment (effectiveness, equitability), spatial planning (key biodiversity area), and action planning (value, outcome, objective). Our standard lexicon can provide a common language for people who want to use it and a shared reference point that can be used to translate various terms used by different groups. The common understanding provided by the lexicon can serve as a foundation for collaborative efforts to improve the policies, implementation, assessments, research, and learning about this important set of conservation approaches.

Chemical warfare agents and their risk assessment in Daphnia magna and fish in the Baltic Sea – 15 years of measurements

The Baltic Sea is one of the world's largest brackish waters, it is drained through the Danish Straits into the Kattegat, and almost enclosed by nine countries. The Baltic Sea is one of the world's most polluted water bodies thus facing a wide range of environmental threats towards its water resources, such as fish stocks, and coastal environments and economics. Chemical warfare agents (CWAs) that were dumped following the Second World War are known to occur in intact or degraded states in sediments and are documented to affect benthic fauna and fish as well as having injured fishermen having accidentally caught lumps of CWAs in their nets. However, a thorough mapping of remaining CWAs and degradation products and an understanding of the environmental risks does not exist although more than 75 years have passed. This study compiles and analyzes published/peer-reviewed data, generated since 2005 in five selected comprehensive studies, on sediment measurements of known dumped CWAs and degradation products in the Baltic Sea. As a worst-case approach, sediment concentrations are transformed to concentrations in near-bottom water, which represents Predicted Environmental Concentrations (PECs) to marine biota. To investigate the accuracy and representativeness of toxicological values, which are fundamental in risk assessments, two cases are considered: Case 1 (specificity) uses toxicological data (EC50 or NOEC) for Daphnia magna and fish with applied assessment factors (AF) to derive Predicted No-Effect Concentrations (PNECs) for organoarsenical and non-arsenical CWAs; Case 2 (robustness) uses partly Danish Environmental Quality Standards (DK EQS) for arsenicals, and partly a Water Quality Criterion (WQC) for arsenicals, representing the marine environment. From 872 data points risk quotients (RQs=PEC/PNEC) are calculated. In Case 1 exceedances of risk for the sum of chemicals (sumRQ>1) occur 24 and 1 times for Daphnia magna and fish, respectively, without applying AFs. 263 and 120 exceedances are found for Daphnia magna and fish, respectively, when applying AFs. Case 2 shows 0 (WQC) and 25 (DK EQS) exceedances for arsenicals when using more robust toxicological values, however, at the expense of specificity of chemicals and target species. The results underline the importance of obtaining more representative and accurate toxicological data (lowering AFs) in order to increase the accuracy of the risk estimates. This quantitative state of risk towards representative marine species indicates that there are indeed potential risks, and it qualifies the understanding and debate on the challenges and future actions regarding dumped chemical munitions in the Baltic Sea.

ANALISIS KADAR KARBOHIDRAT PADA TEH CELUP BERBAHAN DASAR DAUN LAMUN (Enhalus acoroides)

Background: Seagrass is the only flowering plant (angiosperm) that has true root and leaf rhizomes that live submerged in the sea. There are 60 species of seagrass scattered in the world's coastal waters, one type of seagrass that can be used by humans is the seagrass Enhalus acoroides. The economic advantage of Enhalus acoroides leaves can be used as a food ingredient because it has a complete and relatively high nutritional content. Enhalus acoroides leaves can be used as raw material for herbal teas. Herbal teas have a high carbohydrate content, for example in Camellia sinensis tea of ​​0.286%, carbohydrates are one of the chemicals that are needed by the human body. Methods: This study was a descriptive study to determine the value of carbohydrate content in seagrass (Enhalus acoroides) leaf teabags. The research was carried out in March 2022. Sampling of seagrass leaves was carried out in Suli Village, Salahutu District, Central Maluku Regency. The stage of making seagrass teabags was carried out at the Basic Biology Laboratory of FKIP Pattimura University. And the analysis of carbohydrate content was carried out at the Biochemistry Laboratory of the Faculty of Mathematics and Natural Sciences, Pattimura University, Ambon with the type of experimental research. Results: Based on the observations that have been made, the results showed that the carbohydrate content of TL U1 was 5.148%, TL U2 was 5.211%l, TL U3 was 5.165%. With an average carbohydrate of 5.174%. Conclusion: Seagrass leaf teabags (Enhalus acoroides) have a high carbohydrate content and can be a new product that is rich in nutrients.

Aperture-averaged scintillation for a weak underwater turbulence-affected Gaussian beam using the OTOPS model.

The calculation of optical system performance for laser beam propagation in optical turbulence, such as bit error rate (BER), signal-to-noise ratio, and probability of fade, requires the knowledge of scintillation. In this paper, we show the analytical expressions of the aperture-averaged scintillation using a new recently introduced power spectrum of the refractive index fluctuations for underwater turbulence, the oceanic turbulence optical power spectrum (OTOPS). In addition, we use this main result to investigate the impact of weak oceanic turbulence on free-space optical system performance for a propagating Gaussian beam wave. Similar to the atmospheric turbulence case, results show that aperture averaging can reduce the mean BER and the probability of fade several orders of magnitude if the receiver aperture is chosen with a diameter larger than the Fresnel zone, L/k. Being valid for weak turbulence regime in any natural waters, results present the variations of irradiance fluctuations and the performance of underwater optical wireless communication systems depending on the practical values of average temperature and average salinity concentration that can be encountered in any world's waters.

The Impact of Different Drugs on Daphnias Capacity to Survive, Growth, and Reproduce

Abstract: There may be drugs in many of the world's surface waters, but not much is known about how these chemicals affect aquatic life. We used Daphnia magna, a common species of freshwater zooplankton, to test how dangerous single drugs and drug combinations are in water. During both the short-term and long-term pharmacological bioassays, we looked at the life span, appearance, size, number of eggs laid at rest, number of offspring, and percentage of males in the population. We also looked at the rates of death among newborns. The acute stage only lasted six days, but the chronic stage lasted thirty (sex ratio). The Daphnia with a single drug at concentrations ranging from 1 to 100 lg/l didn't change how the organism normally worked. When clofibric acid was given to Daphnia at a concentration of 10 lg/l, their ability to reproduce was much better than when they were given fluoxetine at a concentration of 36 lg/l. Both of these outcomes were better than expected. When fluoxetine at 36 lg/l and clofibric acid at 100 lg/l were given together, they killed a lot of people. When the same dose of fluoxetine was mixed with 10 lg/l of clofibric acid, it caused the carapaces to be misshapen and the setae to move around. The number of males to females in a Daphnia culture changed after it was given three to five antibiotics at doses between 30 and 500 lg/l.

Shipping accident analysis in restricted waters: Lesson from the Suez Canal blockage in 2021

Global shipping flows through strategically important restricted waters such as Panama and Suez Canals, and hence accidents occurring in the Canals will cause serious disruptions to global supply chains. In this paper, a new data-driven Bayesian network (BN) based risk model is developed to investigate how risk factors jointly generate impact on different types of maritime accidents within restricted waters. A new risk database involving 25 factors has been developed by manual analysis of all the recorded accidents from 2005 to 2021 that occurred in the world's important restricted waters including key maritime canals, channels and straits. A data-driven BN model is constructed to analyse the key risk influential factors (RIFs) contributing to such accidents. The model is verified by sensitivity analysis and real accident cases. Further, it is tested by the already known information of the 2021 Suez Canal blockage case to generate useful insights and draw the lessons to learn. In a retrospective analysis using the currently available limited information on the Suez Canal case, the implication of the case study shows a plausible explanation for the observed findings by scenario analysis. The findings can be applied to backward risk cause diagnosis for accident investigation and forward risk prediction for accident prevention in restricted waters to avoid the reoccurrence of similar accident to the Suze Canal blockage.

Global meta‐analysis reveals diverse effects of microplastics on freshwater and marine fishes

AbstractMicroplastic debris is a globally ubiquitous pollutant with diverse consequences for fishes, ranging from severe negative impacts to neutral, or even, positive effects. In the present study, we conducted a systematic review and meta‐analysis of experimental and observational studies to test for the impacts of microplastic exposure on freshwater, estuarine and marine fishes across diverse taxonomies, geographies, and ecosystem contexts. We report evidence for the detrimental, albeit variable, impacts of microplastics, including reduced consumption, altered feeding behavior, obstructed digestion and assimilation, decreased growth, and compromised immunity. By contrast, microplastics appeared to invoke neutral responses in several other ecological and physiological processes, such as body condition, fecundity, hatching success and survival. The results from this study also point to the mismatch between the types, shapes, and sizes of microplastics investigated in experimental settings versus those found in fish in the wild, as well as a striking difference between the 728 fish species investigated for microplastic contamination in the wild versus the only 22 fish species evaluated for the effects of microplastics in the laboratory. The present study reiterates the necessity for more consistent methodological approaches to analyzing and reporting the effects of microplastic exposure, including greater taxonomic breadth and the use of environmentally relevant polymers in future studies. Furthermore, model simulations that explore individual‐ and population‐level implications of realistic exposure scenarios are needed. Overall, the current weight of evidence supports continued management and policy actions to reduce the microplastic production, use, and release into the world's waters.

The Latest Developments in Radiation-Grafted Anion-Exchange Polymer Electrolytes for Low Temperature Electrochemical Systems

Anion-exchange membranes (AEM) are being developed for use in electrochemical technologies including fuel cells (AEMFC),water electrolysis (AEMWE for green hydrogen), electrolysers for CO2 reduction (CO2RR), and reverse electrodialysis (RED). Radiation-grafted AEMs (RG-AEM) represent a promising class of AEM that can exhibit high conductivities (OH- conductivities of > 200 mS cm-1 at temperatures above 60 °C) and favourable in situ water transport characteristics). Hence, RG-AEMs have shown significant promise when tested in AEMFCs alongside powdered radiation-grafted anion-exchange ionomers (RG-AEI), producing high performances and promising durabilities [Energy Environ. Sci., 12, 1575 (2019) and Nature Commun., 11, 3561 (2020)], even at temperatures above 100 °C [Dekel et al., J. Power Sources Adv., 5, 100023 (2020)].An Achilles heel with RG-AEM types is that they can swell excessively in water and have large dimensional changes between the dehydrated and hydrated states. This limits the ion-exchange capacities (IEC) that can be used: excessive IECs in RG-AEM will cause excessive swelling and poorer robustness. This clearly indicates that additional crosslinking is needed. As Kohl et al. have highlighted, optimised crosslinking can lead to production of high-IEC AEMs that are both robust enough to be < 20 µm in thickness and also low swelling [e.g. J. Electrochem. Soc., 166, F637 (2019)], allowing truly world-leading AEMFC performances.RG-AEMs are also being used as a screening platform for down-selecting different (cationic) head-group chemistries for use in RED cells (a salinity gradient power technology), where different head-groups may lead to different AEM characteristics such as: in-cell resistance (when in contact with aqueous electrolytes), permselectivity, and fouling characteristics (when real world waters such as industrial brines, seawater and freshwater are used). It was evident very early on in these studies that RG-AEMs (desirably) exhibit extremely low resistances but also (undesirably) very low permselectivities when un-crosslinked (less than the required 90%+ permselectivity). Our work on RG-type cation-exchange membranes [Sustainable Energy Fuels, 3, 1682 (2019)] clearly shows that introduction of crosslinking can improve permselectivity.Crosslinking always involves a compromise, where its introduction can improve a membrane characteristic (e.g. reduced swelling or improved permselectivity) but also leads to lower conductivities or poorer transport of chemical species through the membranes. Hence, crosslinking types and levels need to be carefully controlled. With RG-AEMs (made by electron-beam activation (peroxidation) of inert polymer films, followed by grafting of monomers and post-graft amination), we have a choice of introducing crosslinking at various stages. The figure below summarises the two different approaches to crosslinking that will be discussed in the presentation: adding a divinyl-type crosslinker into the grafting mixture or adding a diamine-type crosslinker into the amination step.This presentation will present a selection of recent RG-AEM and RG-AEI developments from a number of projects:(1) REDAEM: AEMs for RED cells [EPSRC Grant EP/R044163/1];(2) CARAEM: Novel RG-AEMs for AEMFCs and AEMWE [EPSRC Grant EP/T009233/1];(3) SELECTCO2: RG-AEMs being tested in CO2RR cells [EU Horizon 2020 grant agreement 851441].This presentation will show:(a) RG-AEMs made from thin high density polyethylene (HDPE) precursors appear better for application in AEMFCs, while RG-AEMs from made from thicker ETFE precursors appear to be better for CO2RR cells and RED;(b) RG-AEMs can be made using a variety of crosslinking strategies;(c) RG-AEIs can be made using ETFE powders and give optimal performance after cryogrinding down to micrometer sizes; Figure 1

Occurrence, source apportionment, and pollution assessment of per- and polyfluoroalkyl substances in a river across rural and urban areas

Forty-three novel and legacy per- and polyfluoroalkyl substances (PFASs) in water and sediments from the Chaobai River (Beijing) were quantified. The total PFASs concentrations varied from 0.04 to 31.3 ng/L in water with significant spatial but insignificant seasonal variations, and changed from 0.03 to 4.29 ng/g in sediment with insignificant spatial but significant seasonal variations. The PFASs concentrations in water from the upstream across the rural area reflected the background level due to the extremely low concentration and very few detected PFASs. The consumer products and metal plating/textile were the predominant pollution sources of PFASs in winter and summer, respectively, for both water and sediment samples. Integrating the determined baseline value, the distribution of PFASs concentrations, and the ecological risks of PFASs, three criteria were proposed, which divide the PFASs concentrations in water into four pollution levels, i.e., insignificant, low, medium, and high. According to the suggested criteria, 96.4% of the PFASs levels in upstream was insignificant pollution, which decreased to 50.4% in downstream and 50.8% in reservoirs. The PFASs in China's and world's surface waters demonstrated similar pollution patterns, with PFOA, PFOS, and PFHxA being the top 3 polluted PFASs. This study makes a small step forward the development of water quality standard for PFASs, which is of great importance for pollution control and risk management of PFASs.

温度、盐度对海月水母碟状体生长及存活的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 温度、盐度对海月水母碟状体生长及存活的影响 DOI: 10.5846/stxb202011092876 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金资助项目 (41906138，31770458)；辽宁省农业科学院院长基金项目(2021MS0505)；大连市高层次人才创新支持计划项目(2019RQ064) Effects of temperature and salinity on the growth and survival of moon jellyfish (Aurelia coerulea) ephyrae Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:海月水母为我国近海主要大型灾害水母种类之一,当自然环境适宜其生长与繁殖时,易出现暴发性的增殖现象,严重破坏了我国近岸海洋生态系统的稳点与平衡。采用实验生态学方法,研究了温度(2.5、5、7.5、10、15、20、25、27.5、30℃)和盐度(15、20、25、30、35、40)对海月水母碟状体存活与生长的影响,实验共进行30d。结果显示,在实验设置的温盐范围内,温度、盐度均显著影响碟状体的存活与生长。在盐度15-35条件下,海月水母碟状体可以在温度2.5-25℃存活,在15-25℃范围内可正常生长;在温度20-25℃和盐度20-30条件下适宜海月水母碟状体生长,其中温度20℃和盐度25条件下海月水母碟状体特定生长率达到最大。与盐度相比,温度对碟状体的影响较大,在盐度15-35条件下,随着温度的升高,碟状体的伞径逐渐增大,其碟状体形态向水母体形态的转变速度加快。在达到临界点25℃时,若继续升高温度,碟状体的生存率与生长率显著下降。温度与盐度对海月水母碟状体的生存与生长具有明显的交互效应,碟状体在实验过程中表现出在较低温度条件下提高了对较高盐度的适应性。研究表明,温度、盐度的变化显著影响碟状体的生长与存活,直接导致碟状体种群数量变动,进而影响成熟水母体种群数量。结论为进一步探索大型水母暴发的生态环境机理提供重要科学依据。 Abstract:Gelatinous zooplankton are recognized as key components of aquatic ecosystems, and their outbreaks have been examined in recent years. The moon jellyfish Aurelia coerulea is one of the most common gelatinous zooplankton inhabiting many parts of the world's coastal waters, and outbreaks of this species have been reported from various regions. A key step toward better knowledge of the causes and mechanisms of mass occurrences in scyphozoan jellyfish is to assess the extent of environmentally-induced effects on the phenotype of different phases in their complex life cycle. Moon jellyfish Aurelia coerulea has been reported to have high mortality during the ephyra stage, which potentially affects the population size of the later medusa stage. The effects of the physical environment, especially temperature and salinity, are even more unclear. Laboratory experiments were carried out to quantify the extent of environmentally induced changes in Aurelia coerulea ephyrae morphology, and subsequent effects on ephyrae growth and survival, in response to temperature and salinity. We tested the effects of temperature (2.5, 5, 7.5, 10, 15, 20, 25, 27.5 and 30 ℃) and salinity (15, 20, 25, 30, 35 and 40) on the survival and growth under control conditions. The experiment lasted for 30 days. Results showed that both temperature and salinity significantly affected the ephyrae development, growth and survival. In the salinity 15-35, the ephyrae could survival under 2.5-25℃, and grow in 15-25℃.The suitable temperature and salinity for the survival and growth of the jellyfish ephyrae was 20-25℃ and 20-30. The bell diameter of ephyrae at 20℃ and 25 was the highest. Compared with the salinity, the effect of temperature on the survival and growth of ephyrae was more significantly. In the salinity of 15-35, the bell diameter of ephyrae increased with the temperature increased and the duration of development shortened and mortality decreased as the temperature increased in 2.5℃ to 25℃.There were significant interactions between temperature and salinity on the ephyrae, which manifested as with the temperature decreasing, the adaptability of ephyrae to higher salinity was enhanced. The results showed that in salinity of 40, the survival of ephyrae in lower temperature groups (2.5-15℃) were higher than those in higher temperature groups (20-30℃). In temperature 5-15 ℃, the specific growth rate of ephyrae was higher in salinity of 35 than those in other salinity groups, whereas the highest special growth rate was in salinity of 20 under the temperature groups 20 and 25℃. The suitable temperature and salinity in the field would therefore elevate ephyrae survival rate, accelerate individual development, and thus ensure the population size of medusae. The results will play a very important role in making clear the seasonal dynamic changes of ephyrae population and revealing the outbreak mechanism. 参考文献 相似文献 引证文献

(Invited) Cross-Linked Radiation-Grafted Anion-Exchange Membranes for Energy Conversion Systems: When to Cross-Link?

Anion-exchange membranes (AEM) are being developed for use in a wide range of electrochemical energy technologies including fuel cells (AEMFC), H2-generating electrolysers (AEM-WE), CO2 reduction cells (CO2ER), and reverse electrodialysis (RED). An interesting class of AEM is radiation-grafted types (RG-AEM), which can exhibit very high conductivities and favourable in situ water transport characteristics. Hence, RG-AEM have shown significant promise in application in AEMFCs, producing high performances and promising durabilities [Energy Environ. Sci., 12, 1575 (2019) and Nature Commun., 11, 3561 (2020)]. An Achilles heel with RG-AEM types is that they can swell excessively in water and have large dimensional changes between the dehydrated and hydrated states. This limits the ion-exchange capacities (IEC) that can be used: excessive IECs in RG-AEM will cause excessive swelling and poorer robustness. This clearly indicates that additional crosslinking is needed. As Kohl et al. have highlighted, optimised crosslinking can lead to production of high-IEC AEMs that are both robust enough to be < 20 µm in thickness and also low swelling [e.g. J. Electrochem. Soc., 166, F637 (2019)], allowing truly world-leading AEMFC performances.RG-AEMs are also being used as a screening platform for down-selecting different (cationic) head-group chemistries for use in RED cells (a salinity gradient power technology) [active UK EPSRC grant EP/R044163/1], where different head-groups may lead to different AEM characteristics such as: in-cell resistance (when in contact with aqueous electrolytes), permselectivity, and fouling characteristics (when real world waters such as industrial brines, seawater and freshwater are used). It was evident very early on in these studies that RG-AEMs (desirably) exhibit extremely low resistances but also (undesirably) very low permselectivities when un-crosslinked (less than the required 90%+). Our work on RG-type cation-exchange membranes [Sustainable Energy Fuels, 3, 1682 (2019)] clearly shows that introduction of crosslinking can improve permselectivity.Crosslinking always involves a compromise, where its introduction can improve a membrane characteristic (e.g. reduced swelling or improved permselectivity) but also leads to lower conductivities or poorer transport of chemical species through the membranes. Hence, crosslinking types and levels need to be carefully controlled. With RG-AEMs (made by electron-beam activation (peroxidation) of inert polymer films, followed by grafting of monomers and post-graft amination), we have a choice of introducing crosslinking at various stages. The figure below summarises the two different approaches to crosslinking that will be discussed in the presentation: adding a divinyl-type crosslinker into the grafting mixture or adding a diamine-type crosslinker into the amination step.This presentation will present the results from an initial investigation of these two crosslinking approaches. As well as crosslinking in the amination stage being practically easier and more repeatable (we used N,N,N',N'-tetramethyl-1,6-hexane diamine (TMHDA) as a model diamine, being readily commercially available) compared to adding divinylbenzene (DVB – a model commercially available divinyl crosslinking agent) in the grafting step, we will show that such diamine crosslinking also enhances desirable properties (such as permselectivity) with less sacrifice of conductivity (less increases in resistance) compared to the use of DVB crosslinking. Figure 1

Size, shape, and diversity in phytoplankton

Cell Morphology Phytoplankton, the unicellular photosynthetic organisms of the world's surface waters, display a bewildering variety of cell shapes and sizes. Ryabov et al. analyzed how shape relates to taxonomic diversity across a large sample of phytoplanktonic data from a range of oceanic regions. Classifying the sample into 38 geometric shapes, they found that the taxa with the greatest diversity of species tended to be those of compact shape and intermediate volume, whereas diversity decreased exponentially with increased cell elongation and cell surface area. These patterns will contribute to our understanding of the evolutionary and ecological forces shaping planktonic diversity and how accelerating changes in the marine environment might affect future patterns of planktonic community composition. Ecol. Lett. 10.1111/ele.13680 (2021).

Spectral Characteristics of Plastic Debris in the Beach: Case Study of Makassar Coastal Area

Plastic debris becomes a global problem that threatens the coastal ecosystems, and the supralittoral area (beach) turns to be a place for plastic debris to accumulate. Data from the United Nations (UN) states that Indonesia is the second plastic debris contributor in world waters. This study aimed to examine the spectral characteristics of plastic debris accumulated on the beach. The data was collected from the coast of Makassar at 3 different stations: Jenneberang River estuary, Losari Beach and Tallo River estuary. The spectral sample was measured using a 4000 A spectroradiometer that works on a wavelength spectrum of 340 - 1040 nm. The results showed that the optimum value for plastic debris identification in the coastal area at low tide (dry sand) is 450-670 nm and at high tide (wet sand) is 450-950 nm. This value will be a reference in the remote sensing method, especially multispectral classification in mapping plastic debris found in coastal areas, and will be one solution to effectively mapping plastic debris.

Why does N-limitation persist in the world's marine waters?

Primary production of vast regions of the world's estuarine, coastal and pelagic ocean waters is limited by availability of fixed nitrogen; this despite the fact that a highly diverse suite of microorganisms potentially capable of fixing N2 (eubacteria and cyanobacteria), inhabit these waters. Theoretically, diazotrophs should supply the N needs to balance the N required to support primary production, assuming other key limiting nutrients, phosphorus and iron, are available and energy requirements are met. In practice however, N2 fixation often does not meet ecosystem-scale N demands, even when these nutrients are replete. The problem lies with the fact that optimal rates of N2 fixation are often controlled by additional environmental factors, including light and organic matter availability, turbulence, and high levels of dissolved oxygen which can suppress this process in N-deplete surface waters. In addition, rates of N loss via denitrification and anammox can exceed N2 fixation and external N inputs on annual scales in coastal and pelagic waters, including those experiencing eutrophication. This creates a situation where chronic N limitation persists, even in the presence of anthropogenic nitrogen enrichment. Many aquatic ecosystems exhibit a perpetual “hunger” for fixed N to support primary and higher levels of production and this is likely to continue over forseeable biological and geologic timescales.

Why does N-limitation persist in the world's marine waters?

Why does N-limitation persist in the world's marine waters?

A patent defence approach to sharing aquaculture genetic resources across jurisdictional areas

Access and benefit sharing (ABS) of genetic resources is a concept that is increasingly important for product development in aquaculture. ABS regulates the way aquatic genetic resources can be accessed from the world's waters and how the benefits that result from their use are shared between the providers and users of genetic resources and their derivatives. This article gives an overview of the multiple approaches to sharing aquaculture genetic resources under ABS regimes across the three jurisdictional areas in which they are found—waters within national jurisdiction, beyond national jurisdictions and in the Antarctic Treaty Area. It highlights the complexity and inconsistencies relating to obligations for technology transfer across the various regimes and the implications this has for sharing genetic resources for use in aquaculture. It offers a practical solution to navigating this complexity by using an evolving patent defence approach consistent with the World Trade Organisation's Agreement on Trade‐Related Aspects of Intellectual Property Rights (TRIPS). It concludes that this approach can guide the resolution of legal challenges that ABS regimes across the jurisdictional areas have in common, which concern derivatives and commercial use of genetic resources.

Modeling global water use for the 21st century: the Water Futures and Solutions (WFaS) initiative and its approaches

Abstract. To sustain growing food demand and increasing standard of living, global water use increased by nearly 6 times during the last 100 years, and continues to grow. As water demands get closer and closer to the water availability in many regions, each drop of water becomes increasingly valuable and water must be managed more efficiently and intensively. However, soaring water use worsens water scarcity conditions already prevalent in semi-arid and arid regions, increasing uncertainty for sustainable food production and economic development. Planning for future development and investments requires that we prepare water projections for the future. However, estimations are complicated because the future of the world's waters will be influenced by a combination of environmental, social, economic, and political factors, and there is only limited knowledge and data available about freshwater resources and how they are being used. The Water Futures and Solutions (WFaS) initiative coordinates its work with other ongoing scenario efforts for the sake of establishing a consistent set of new global water scenarios based on the shared socio-economic pathways (SSPs) and the representative concentration pathways (RCPs). The WFaS "fast-track" assessment uses three global water models, namely H08, PCR-GLOBWB, and WaterGAP. This study assesses the state of the art for estimating and projecting water use regionally and globally in a consistent manner. It provides an overview of different approaches, the uncertainty, strengths and weaknesses of the various estimation methods, types of management and policy decisions for which the current estimation methods are useful. We also discuss additional information most needed to be able to improve water use estimates and be able to assess a greater range of management options across the water–energy–climate nexus.

Ecological research and management of intermittent rivers: an historical review and future directions

SummaryRivers and streams that do not flow permanently (herein intermittent rivers;IRs) make up a large proportion of the world's inland waters and are gaining widespread attention. We review the research onIRs from its early focus on natural history through to current application in management and policy.The few early studies of the ecology ofIRs were largely descriptive. Nevertheless, in the 1970s, synthesis of this sparse research complemented work on temporary standing waters to found a powerful framework for much of the subsequent research onIRs.Research on the ecology and biogeochemistry ofIRs continues to fuel our understanding of resistance and resilience to drying and flooding as disturbances. Syntheses of the growing literature, including cross‐continental and cross‐climate comparisons, are revealing the generality and individuality of ecological and ecosystem responses to flow cessation and surface water loss. Meanwhile, increasing numbers of experiments test the causality of these responses.Much of the increased consideration ofIRs in research, management and policy is driven by the observed and projected shifts in flow regimes from perennial to intermittent associated with changes in land and water use and climate, superimposed on the high incidence of natural intermittency. The need to protect and better manageIRs is prompting researchers to develop new or modified methods to monitor flow status and assess the ecological condition of these systems.Intermittent river research and management will benefit from greater exploration of aquatic–terrestrial linkages, wet–dry cycling and temporal dynamics, more‐detailed mapping and predictive modelling of flow intermittency and the application of metapopulation and metacommunity concepts alongside multiple‐stressors and novel‐ecosystems research. By building on existing knowledge, continuing to develop quantitative models and distribution maps and using experiments to test hypotheses and concepts, we can further ecological understanding and wise management of these ubiquitous ecosystems.

A new geographical record of Polycera hedgpethi Er. Marcus, 1964 (Nudibranchia: Polyceridae) and evidence of its established presence in the Mediterranean Sea, with a review of its geographical distribution

This article reports the first record of the Nudibranch Polycera hedgpethi in the Lagoon of Venice (Italy), as well as its established presence in the Mediterranean Sea after its first record in 1986 in lake Fusaro (Naples). In less than 50 years P. hedgpethi has spread throughout the world's temperate and subtropical waters, preferring protected coastal environments and other semi-enclosed coastal water bodies such as ports, harbours and lagoons. Shipping is the most likely vector. The species distribution shows a temperate–subtropical range, at about 7–45° of latitude both North and South. Polycera hedgpethi was collected during a survey in 2009 and its presence confirmed for the following two years. All individuals collected were found attached to the bryozoan Bugula neritina, to which it is linked trophically, suggesting a determined pattern of distribution. The present finding is the northernmost record for the species.