PeerJ Preprints: Natural Resource Managementhttps://peerj.com/preprints/index.atom?journal=peerj&subject=1415Natural Resource Management articles published in PeerJ PreprintsAll change for climate changehttps://peerj.com/preprints/279822019-09-242019-09-24Tony R Walker
Governments, corporations and individuals all need to take immediate action to help change the global economy toward a circular economy. A circular economy which uses fewer resources and based on renewable clean technologies to help limit global warming to 1.5 °C. The 2018 Intergovernmental Panel on Climate Change (IPCC) report warned that limiting global warming to 1.5 °C above pre-industrial levels would require current greenhouse-gas (GHG) emissions to be cut in half by 2030. Yet actions by governments, corporations and individuals are lagging behind. Many countries are failing their obligations made under the 2015 Paris climate agreement. Even the International Maritime Organization, a United Nations agency set a 50% reduction target of GHG emissions for global shipping by 2050, but this falls short of the IPCC target by 20 years. The United Nations climate summit in New York this week (September 2019) needs to send a strong wake up call to the entire world for us all to change. Change makers like Greta Thunberg has already done that. Individual actions to change consumer behaviour can play a major role to help reduce GHG emissions. Even reducing use of single-use plastics (a petroleum derivative) and incineration can help reduce GHG emissions. GHG emissions from plastics could reach 15% of the global carbon budget by 2050 if not curbed. In Europe, plastic production and incineration emits an estimated ~400 million tonnes of CO2 per year. Therefore, reducing single-use plastic use could curb GHG emissions.
Governments, corporations and individuals all need to take immediate action to help change the global economy toward a circular economy. A circular economy which uses fewer resources and based on renewable clean technologies to help limit global warming to 1.5 °C. The 2018 Intergovernmental Panel on Climate Change (IPCC) report warned that limiting global warming to 1.5 °C above pre-industrial levels would require current greenhouse-gas (GHG) emissions to be cut in half by 2030. Yet actions by governments, corporations and individuals are lagging behind. Many countries are failing their obligations made under the 2015 Paris climate agreement. Even the International Maritime Organization, a United Nations agency set a 50% reduction target of GHG emissions for global shipping by 2050, but this falls short of the IPCC target by 20 years. The United Nations climate summit in New York this week (September 2019) needs to send a strong wake up call to the entire world for us all to change. Change makers like Greta Thunberg has already done that. Individual actions to change consumer behaviour can play a major role to help reduce GHG emissions. Even reducing use of single-use plastics (a petroleum derivative) and incineration can help reduce GHG emissions. GHG emissions from plastics could reach 15% of the global carbon budget by 2050 if not curbed. In Europe, plastic production and incineration emits an estimated ~400 million tonnes of CO2 per year. Therefore, reducing single-use plastic use could curb GHG emissions.Public priorities on locally-driven sea level rise planning on the East Coast of the United Stateshttps://peerj.com/preprints/279332019-09-022019-09-02Adam T Carpenter
Sea Level Rise poses a substantial concern to communities worldwide. Increased inundation, storm surge, salt water intrusion, and other impacts create challenges which will require considerable planning to address. Recognizing the broad and differing scope of sea level rise issues and the variability of policy options to address them, local planning frameworks are necessary in addition to tools and resources available from state and federal governments. To help assess priorities and preferences on sea level rise planning, a survey of 503 persons affiliated with coastal communities on the East Coast of the United States was conducted in December 2017. This survey studied key aspects locally-driven sea level rise plans, including planning priorities, funding options, methods to resolve conflict, and potential responses. Six key findings address these and other concerns to provide the foundation of a locally driven framework for public officials.
Sea Level Rise poses a substantial concern to communities worldwide. Increased inundation, storm surge, salt water intrusion, and other impacts create challenges which will require considerable planning to address. Recognizing the broad and differing scope of sea level rise issues and the variability of policy options to address them, local planning frameworks are necessary in addition to tools and resources available from state and federal governments. To help assess priorities and preferences on sea level rise planning, a survey of 503 persons affiliated with coastal communities on the East Coast of the United States was conducted in December 2017. This survey studied key aspects locally-driven sea level rise plans, including planning priorities, funding options, methods to resolve conflict, and potential responses. Six key findings address these and other concerns to provide the foundation of a locally driven framework for public officials.Governance planning for sustainable oceans in a small island statehttps://peerj.com/preprints/279162019-08-272019-08-27Gerald G SinghMarck OduberAndres Cisneros-MontemayorJorge Ridderstaat
Achieving the Sustainable Development Goals (SDGs) will require coordinated policymaking for achievement. Aruba is a Small Island State (SIDS) with 90% of its jobs and GDP dependent on the oceans has prioritized SDG 14 – life below water, or the SDG Ocean goal – for achievement. We have developed a planning process, building off of the the literature on SDG interactions and stratetic policy planning literatures, to guide SDG policy development and implemented it in Aruba. We used a structured expert elicitation process to carry out the analysis for this process. The process involves first identifying priority areas based on determining which SDG Ocean target provides the most co-benefit across other SDGs. Next we determine the SDG areas that most contribute to key SDG Ocean targets. Using this information we determine the key policy areas important for promoting sustainable oceans. Finally, we determine the Aruban ministries and institutions responsible for the various SDG areas and based on which SDG areas are most important for SDG Ocean achievement we visualize a new institutional network to support the achievement of SDG Oceans. First, we determined that while increasing economic benfits for SIDS (SDG 14.7) was the most important SDG Ocean target when considering direct impacts, reducing marine pollution (SDG 14.1), restoring marine habitats (SDG 14.2), and marine protection (SDG 14.5) were the most important SDG Ocean targets when considering indirect impacts. SDG areas with the most beneficial consequences for the SDG Ocean targets were mitigating climate impacts (SDG 13), international partnerships (SDG 17), jobs and economy (SDG 8), conserving terrestrial area (SDG 15), strengthening institutions (SDG 16), and promoting sustainable consumption and production practices (SDG 12). When links between SDGs are not considered, the institutional network supporting sustainable oceans is relatively simple, with the Department of Nature and the Environment most central: it coordinates across the largest number of relevant institutions supporting the SDG Oceans goal. However, when SDG relationships are considered, the institutional network is relatively complex, and the Social and Economic Council is determined to be the most central and important in coordinating activities across the largest number of Aruban instutions that support the SDG Ocean goal. Transitioning to a sustainable future requires policymaking that works across social-ecological dimensions, and need to design coherent and integrative institutional structures with which to do this.
Achieving the Sustainable Development Goals (SDGs) will require coordinated policymaking for achievement. Aruba is a Small Island State (SIDS) with 90% of its jobs and GDP dependent on the oceans has prioritized SDG 14 – life below water, or the SDG Ocean goal – for achievement. We have developed a planning process, building off of the the literature on SDG interactions and stratetic policy planning literatures, to guide SDG policy development and implemented it in Aruba. We used a structured expert elicitation process to carry out the analysis for this process. The process involves first identifying priority areas based on determining which SDG Ocean target provides the most co-benefit across other SDGs. Next we determine the SDG areas that most contribute to key SDG Ocean targets. Using this information we determine the key policy areas important for promoting sustainable oceans. Finally, we determine the Aruban ministries and institutions responsible for the various SDG areas and based on which SDG areas are most important for SDG Ocean achievement we visualize a new institutional network to support the achievement of SDG Oceans. First, we determined that while increasing economic benfits for SIDS (SDG 14.7) was the most important SDG Ocean target when considering direct impacts, reducing marine pollution (SDG 14.1), restoring marine habitats (SDG 14.2), and marine protection (SDG 14.5) were the most important SDG Ocean targets when considering indirect impacts. SDG areas with the most beneficial consequences for the SDG Ocean targets were mitigating climate impacts (SDG 13), international partnerships (SDG 17), jobs and economy (SDG 8), conserving terrestrial area (SDG 15), strengthening institutions (SDG 16), and promoting sustainable consumption and production practices (SDG 12). When links between SDGs are not considered, the institutional network supporting sustainable oceans is relatively simple, with the Department of Nature and the Environment most central: it coordinates across the largest number of relevant institutions supporting the SDG Oceans goal. However, when SDG relationships are considered, the institutional network is relatively complex, and the Social and Economic Council is determined to be the most central and important in coordinating activities across the largest number of Aruban instutions that support the SDG Ocean goal. Transitioning to a sustainable future requires policymaking that works across social-ecological dimensions, and need to design coherent and integrative institutional structures with which to do this.Natural history of the critically endangered salamander Pseudoeurycea robertsihttps://peerj.com/preprints/279112019-08-202019-08-20Armando SunnyCarmen Caballero-ViñasLuis Duarte-deJesusFabiola Ramírez-CoronaJavier ManjarrezGiovanny González-DesalesXareni P. PachecoOctavio Monroy-VilchisAndrea González-Fernández
Mexico is one of the most diverse countries that is losing a large amount of forest due to land use change, these data put Mexico in fourth place for global deforestation rate, therefore, Mexico occupies the first place in number of endangered species in the world with 665 endangered species. It is important to study amphibians because they are among the most threatened vertebrates on Earth and their populations are rapidly declining worldwide due primarily to the loss and degradation of their natural habitats. Pseudoeurycea robertsi is a micro-endemic and critically endangered Plethodontid salamander from the Nevado de Toluca Volcano and to date almost nothing is known about its natural history therefore, we survey fourteen sites of the Nevado de Toluca Volcano a mountain that is part of the Trans-Mexican Volcanic Belt, Mexico. We carry out the most exhaustive sampling scheme of this species throughout the Nevado de Toluca Volcano to know the number of individuals and the microhabitat features associated with the presence of P. robertsi. Likewise, we carry out a morphometric study and coloration measurements of P. robertsi individuals and we determine the potential distribution of P. robertsi and the other 3 species of pletodontids present in the NTV using ecological niche modeling and to determine the most important habitat features associated with the presence of salamander species, as well as to know the niche overlap among salamander species. This information will help raise conservation strategies for this micro-endemic and critically endangered salamander.
Mexico is one of the most diverse countries that is losing a large amount of forest due to land use change, these data put Mexico in fourth place for global deforestation rate, therefore, Mexico occupies the first place in number of endangered species in the world with 665 endangered species. It is important to study amphibians because they are among the most threatened vertebrates on Earth and their populations are rapidly declining worldwide due primarily to the loss and degradation of their natural habitats. Pseudoeurycea robertsi is a micro-endemic and critically endangered Plethodontid salamander from the Nevado de Toluca Volcano and to date almost nothing is known about its natural history therefore, we survey fourteen sites of the Nevado de Toluca Volcano a mountain that is part of the Trans-Mexican Volcanic Belt, Mexico. We carry out the most exhaustive sampling scheme of this species throughout the Nevado de Toluca Volcano to know the number of individuals and the microhabitat features associated with the presence of P. robertsi. Likewise, we carry out a morphometric study and coloration measurements of P. robertsi individuals and we determine the potential distribution of P. robertsi and the other 3 species of pletodontids present in the NTV using ecological niche modeling and to determine the most important habitat features associated with the presence of salamander species, as well as to know the niche overlap among salamander species. This information will help raise conservation strategies for this micro-endemic and critically endangered salamander.Management options for addressing the persistent and unresolved CITES issue of Madagascar’s rosewood stocks and stockpilehttps://peerj.com/preprints/278892019-08-082019-08-08Lucienne WilméJohn L. InnesDerek SchuurmanBruno RamamonjisoaMarion LangrandCharles V. BarberRhett A. ButlerGeorge WittemyerPatrick O. Waeber
Stocks and stockpiles of CITES (the Convention on International Trade in Endangered Species of wild fauna and flora) listed wildlife, including animal and plant-derived products, remain a complex, unresolved issue. The biggest challenges lie in the prevention of further illegal sourcing of—and trade in—products originating from wild populations of threatened species. Stocks can function as a buffer during lean periods or as a mechanism used for speculation. As we outline in this paper, the current situation in Madagascar precludes non-detriment findings intended to enable sustainable use of standing rosewood populations. Backed by the World Bank, the previous Malagasy government was in the process of promoting the sale of massive stocks and stockpiles of confiscated precious woods in order to reach a zero stocks goal, this being ostensibly to halt the illegal sourcing and trafficking of rosewood. We propose and analyse four potential options for stocks management by presenting a framework linking forest management with socio-economic objectives and comparative risks. Destruction (burning) of the known stocks would send out a strong conservation message and has the strongest chance of halting further sourcing, which happens mostly in protected areas and is therefore illegal. National trade is the option in which a precious timber sector would process the woods in stocks. This option is the most beneficial for development. Opening the stocks for exportation through international trade achieves the smallest number of objectives in relation to both forests and socio-economic indicators, but comes with the highest risks in terms of curbing further illegal logging. Banking represents a fourth option, which essentially postpones any decision related to stocks management by storing the stocks for extended periods. None of the four management options is able to ensure a sustainable solution that can resolve the issues surrounding the precious timber stocks. The approaches put forward are either just ‘more good’, or ‘less good’. If a country is seriously interested in conserving its biodiversity, any government has to ensure that no other sectorial changes will counteract, or potentially undermine, the efforts to protect the environment. Stocks management will be on agenda at the upcoming COP18 in Geneva, 17–28 August 2019.
Stocks and stockpiles of CITES (the Convention on International Trade in Endangered Species of wild fauna and flora) listed wildlife, including animal and plant-derived products, remain a complex, unresolved issue. The biggest challenges lie in the prevention of further illegal sourcing of—and trade in—products originating from wild populations of threatened species. Stocks can function as a buffer during lean periods or as a mechanism used for speculation. As we outline in this paper, the current situation in Madagascar precludes non-detriment findings intended to enable sustainable use of standing rosewood populations. Backed by the World Bank, the previous Malagasy government was in the process of promoting the sale of massive stocks and stockpiles of confiscated precious woods in order to reach a zero stocks goal, this being ostensibly to halt the illegal sourcing and trafficking of rosewood. We propose and analyse four potential options for stocks management by presenting a framework linking forest management with socio-economic objectives and comparative risks. Destruction (burning) of the known stocks would send out a strong conservation message and has the strongest chance of halting further sourcing, which happens mostly in protected areas and is therefore illegal. National trade is the option in which a precious timber sector would process the woods in stocks. This option is the most beneficial for development. Opening the stocks for exportation through international trade achieves the smallest number of objectives in relation to both forests and socio-economic indicators, but comes with the highest risks in terms of curbing further illegal logging. Banking represents a fourth option, which essentially postpones any decision related to stocks management by storing the stocks for extended periods. None of the four management options is able to ensure a sustainable solution that can resolve the issues surrounding the precious timber stocks. The approaches put forward are either just ‘more good’, or ‘less good’. If a country is seriously interested in conserving its biodiversity, any government has to ensure that no other sectorial changes will counteract, or potentially undermine, the efforts to protect the environment. Stocks management will be on agenda at the upcoming COP18 in Geneva, 17–28 August 2019.Twisted tale of the tiger: the case of inappropriate data and deficient sciencehttps://peerj.com/preprints/273492019-07-312019-07-31Qamar QureshiRajesh GopalYadvendradev V Jhala
Publications in peer reviewed journals are often looked upon as tenets on which future scientific thought is built. Published information is not always flawless and errors in published research should be expediently reported, preferably by a peer review process. We review a recent publication by Gopalaswamy et al (doi:10.1111/2041-210X.12351) that challenges the use of “double sampling” in large scale animal surveys. Double sampling is often resorted to as an established economical and practical approach for large scale surveys since it calibrates abundance indices against absolute abundance, thereby potentially addressing the statistical shortfalls of indices. Empirical data used by Gopalaswamy et al. to test their theoretical model, relate to tiger sign and tiger abundance referred to as an Index Calibration experiment (IC-Karanth). These data on tiger abundance and signs should be paired in time and space to qualify as a calibration experiment for double sampling, but original data of IC-Karanth show lags of (up to) several years. Further, data points used in the paper do not match the original sources. We show that by use of inappropriate and incorrect data collected through a faulty experimental design, poor parameterization of their theoretical model, and selectively-picked estimates from literature on detection probability, the inferences of this paper are highly questionable. We highlight how the results of Gopalaswamy et al. were further distorted in popular media. If left unaddressed, Gopalaswamy et al. paper could have serious implications on statistical design of large-scale animal surveys by propagating unreliable inferences.
Publications in peer reviewed journals are often looked upon as tenets on which future scientific thought is built. Published information is not always flawless and errors in published research should be expediently reported, preferably by a peer review process. We review a recent publication by Gopalaswamy et al (doi:10.1111/2041-210X.12351) that challenges the use of “double sampling” in large scale animal surveys. Double sampling is often resorted to as an established economical and practical approach for large scale surveys since it calibrates abundance indices against absolute abundance, thereby potentially addressing the statistical shortfalls of indices. Empirical data used by Gopalaswamy et al. to test their theoretical model, relate to tiger sign and tiger abundance referred to as an Index Calibration experiment (IC-Karanth). These data on tiger abundance and signs should be paired in time and space to qualify as a calibration experiment for double sampling, but original data of IC-Karanth show lags of (up to) several years. Further, data points used in the paper do not match the original sources. We show that by use of inappropriate and incorrect data collected through a faulty experimental design, poor parameterization of their theoretical model, and selectively-picked estimates from literature on detection probability, the inferences of this paper are highly questionable. We highlight how the results of Gopalaswamy et al. were further distorted in popular media. If left unaddressed, Gopalaswamy et al. paper could have serious implications on statistical design of large-scale animal surveys by propagating unreliable inferences.Public opinion of captive cetacean attractions: A critique of Wassermannet al. (2018)https://peerj.com/preprints/278522019-07-112019-07-11Heather M Manitzas HillKelly Jaakkola
Wassermann et al. (2018, https://doi.org/10.7717/peerj.5953) argued that previous public opinion research about marine mammal attractions should be considered unreliable due to possible biases in study design, which may have influenced participants’ responses. As in all scientific endeavors, reducing bias in order to gather more objective, evidence-based information is a worthy and commendable goal. Unfortunately, Wassermann et al. fell short in their efforts to produce an unbiased investigation into the beliefs of the general public about captive marine mammal attractions, due to a number of methodological flaws and biases in their own study. Specific concerns include a non-representative sample, methodological issues with data collection and coding procedures, a lack of reliability between data published and data provided, a failure to demonstrate inter-coder reliability, a failure to control for sequence effects in quantitative data, misrepresentation of databetween text and tables, and biased over-interpretation of qualitative responses. These errors undermine the authors’ conclusions and indeed render their findings uninterpretable. To achieve the goal of an unbiased understanding of public opinion about marine mammal attractions, further research on this topic is warranted using rigorous and sound scientific methodology.
Wassermann et al. (2018, https://doi.org/10.7717/peerj.5953) argued that previous public opinion research about marine mammal attractions should be considered unreliable due to possible biases in study design, which may have influenced participants’ responses. As in all scientific endeavors, reducing bias in order to gather more objective, evidence-based information is a worthy and commendable goal. Unfortunately, Wassermann et al. fell short in their efforts to produce an unbiased investigation into the beliefs of the general public about captive marine mammal attractions, due to a number of methodological flaws and biases in their own study. Specific concerns include a non-representative sample, methodological issues with data collection and coding procedures, a lack of reliability between data published and data provided, a failure to demonstrate inter-coder reliability, a failure to control for sequence effects in quantitative data, misrepresentation of databetween text and tables, and biased over-interpretation of qualitative responses. These errors undermine the authors’ conclusions and indeed render their findings uninterpretable. To achieve the goal of an unbiased understanding of public opinion about marine mammal attractions, further research on this topic is warranted using rigorous and sound scientific methodology.Variation characteristics of stem water content in Lagerstroemia indica and its response to microenvironmenthttps://peerj.com/preprints/277722019-06-022019-06-02Hao LiangMeng ZhangYandong ZhaoChao GaoHailan Wang
To achieve a rational allocation of limited water resources, and formulation of an appropriate irrigation system, this research studied the change characteristics of stem water content (StWC) in plant and its response to micro-environmental factors. In this study, the StWC and micro-environmental factors of Lagerstroemia indica in Beijing were continuously observed by BD-IV plant stem water content sensor and a forest microclimate monitoring station from 2017 to 2018. The variation of StWC and its correlation with environmental factors were analyzed. The results showed the StWC of Lagerstroemia indica varies regularly day and night during the growth cycle. Meanwhile, the rising time, valley time, and falling time of StWC were various at the different growth stages of Lagerstroemia indica. The results of correlation analysis between StWC and micro-environmental factors indicated that the StWC of Lagerstroemia indica was positively correlated with air relative humidity, while it was negatively correlated with total radiation and air temperature. The multiple regression equation of StWC and micro-environmental factors of Lagerstroemia indica was StWC = 11.789-1.402Rn-0.931T-1.132Ws+0.933RH-3.368ST+2.168SMC, and the coefficient of determination of the equation was of 0.87. Furthermore, the results illustrated that the irrigation should pay attention to supplementing irrigation in time during the peak growing season of fruit.
To achieve a rational allocation of limited water resources, and formulation of an appropriate irrigation system, this research studied the change characteristics of stem water content (StWC) in plant and its response to micro-environmental factors. In this study, the StWC and micro-environmental factors of Lagerstroemia indica in Beijing were continuously observed by BD-IV plant stem water content sensor and a forest microclimate monitoring station from 2017 to 2018. The variation of StWC and its correlation with environmental factors were analyzed. The results showed the StWC of Lagerstroemia indica varies regularly day and night during the growth cycle. Meanwhile, the rising time, valley time, and falling time of StWC were various at the different growth stages of Lagerstroemia indica. The results of correlation analysis between StWC and micro-environmental factors indicated that the StWC of Lagerstroemia indica was positively correlated with air relative humidity, while it was negatively correlated with total radiation and air temperature. The multiple regression equation of StWC and micro-environmental factors of Lagerstroemia indica was StWC = 11.789-1.402Rn-0.931T-1.132Ws+0.933RH-3.368ST+2.168SMC, and the coefficient of determination of the equation was of 0.87. Furthermore, the results illustrated that the irrigation should pay attention to supplementing irrigation in time during the peak growing season of fruit.Seismic stratigraphy of the broad, low-gradient continental shelf of the Palaeo-Agulhas Plain, South Africahttps://peerj.com/preprints/277572019-05-242019-05-24Hayley C CawthraPeter FrenzelAnnette HahnJohn ComptonLukas GanderMatthias Zabel
The continental shelf of the Palaeo-Agulhas Plain (PAP) is scattered with Pleistocene deposits with subdued topography. Their exaggerated lateral extension is the expression of a flat underlying substrate and availability of accommodation space, depositional processes and response to glacio-eustatic sea-level change have influenced deposition and distribution of these units. We present new results for the upper ~30 m (up to ~200 ka) of the stratigraphic record in this area and show that this shelf offers the opportunity to examine the response of a stable tectonic setting to the effects of sea-level change. This paper presents the results of extensive sub-bottom profiling surveys and chronostratigraphic investigations from marine sediment vibracores. Radiocarbon and Optically stimulated Luminescence dates are integrated into a seismic stratigraphic model composed of twenty Quaternary units, where two depositional sequences are bounded by shelf-wide unconformities. The upper sequence was cored where Pleistocene deposits were observed to be close to the seafloor and are draped in a thin veneer of marine shelf sediment and allow us to describe the environments of deposition of the PAP. The most pervasive stratigraphic pattern in these shelf deposits is made up of the depositional sequence remnant of the Falling Stage Systems Tract (FSST) forced regression from Marine Isotope Stage 5e–2. The other dominant stratigraphic group is the Transgressive Systems Tract (TST) associated with the Postglacial Marine Transgression. Surprisingly, the TST makes up an almost equal proportion of deposits in both sequences in the sedimentological record as the FSST, despite the shorter temporal span of the TST. The sub-bottom profiles were acquired on regional surveys extending from the Breede River in the west to Plettenberg Bay in the east, and to a maximum depth of 110 m below Mean Sea Level, with the exception of one ~200 m deep shelf-edge profile.
The continental shelf of the Palaeo-Agulhas Plain (PAP) is scattered with Pleistocene deposits with subdued topography. Their exaggerated lateral extension is the expression of a flat underlying substrate and availability of accommodation space, depositional processes and response to glacio-eustatic sea-level change have influenced deposition and distribution of these units. We present new results for the upper ~30 m (up to ~200 ka) of the stratigraphic record in this area and show that this shelf offers the opportunity to examine the response of a stable tectonic setting to the effects of sea-level change. This paper presents the results of extensive sub-bottom profiling surveys and chronostratigraphic investigations from marine sediment vibracores. Radiocarbon and Optically stimulated Luminescence dates are integrated into a seismic stratigraphic model composed of twenty Quaternary units, where two depositional sequences are bounded by shelf-wide unconformities. The upper sequence was cored where Pleistocene deposits were observed to be close to the seafloor and are draped in a thin veneer of marine shelf sediment and allow us to describe the environments of deposition of the PAP. The most pervasive stratigraphic pattern in these shelf deposits is made up of the depositional sequence remnant of the Falling Stage Systems Tract (FSST) forced regression from Marine Isotope Stage 5e–2. The other dominant stratigraphic group is the Transgressive Systems Tract (TST) associated with the Postglacial Marine Transgression. Surprisingly, the TST makes up an almost equal proportion of deposits in both sequences in the sedimentological record as the FSST, despite the shorter temporal span of the TST. The sub-bottom profiles were acquired on regional surveys extending from the Breede River in the west to Plettenberg Bay in the east, and to a maximum depth of 110 m below Mean Sea Level, with the exception of one ~200 m deep shelf-edge profile.Off-line and on-line optical monitoring of microalgal growthhttps://peerj.com/preprints/277442019-05-192019-05-19Hugo-Enrique Lazcano-HernandezGabriela AguilarGabriela DzulRodrigo PatiñoJavier Arellano-Verdejo
The growth of Chlamydomonas reinhardtii microalgae cultures was successfully monitored, from classic off-line optical techniques (optical density and fluorescence) to on-line analysis of digital images. In this study, it is shown that the chlorophyll fluorescence ratio F685/F740 has a linear correlation with the logarithmic concentration of microalgae. Moreover, with digital images, the biomass concentration was correlated with: the luminosity of the images through an exponential equation, and the length of penetration of a superluminescent blue beam (λ=440 nm), through an inversely proportional function. Outcomes of this study are useful to monitor both research and industrial microalgae cultures.
The growth of Chlamydomonas reinhardtii microalgae cultures was successfully monitored, from classic off-line optical techniques (optical density and fluorescence) to on-line analysis of digital images. In this study, it is shown that the chlorophyll fluorescence ratio F685/F740 has a linear correlation with the logarithmic concentration of microalgae. Moreover, with digital images, the biomass concentration was correlated with: the luminosity of the images through an exponential equation, and the length of penetration of a superluminescent blue beam (λ=440 nm), through an inversely proportional function. Outcomes of this study are useful to monitor both research and industrial microalgae cultures.