Variation of lipid class composition in Nitzschia laevis as a response to growth temperature change.

Three local isolates of the green alga Tetraselmis sp. identified as the most promising microalgae species for outdoor mass cultivation with high potential for biodiesel production due to high amounts of total lipids and high lipid productivity were employed in this study. The aim of the study was to compare three halophilic Tetraselmis strains (Tetraselmis MUR-167, MUR-230 and MUR-233) grown in open raceway ponds over long periods with respect to their specific growth rate and lipid productivity without additional CO2 and with CO2 addition regulated at pH 7.5 by using a pH-stat system. Attention also was given to the overall culture condition including contaminating organisms, biofilm development due to cell adhesion and cell clump formation. 

All tested Tetraselmis strains in this study were successfully grown outdoors in open raceway ponds in hypersaline fertilised medium at 7 % w/v NaCl over a period of more than two years. A marked effect of CO2 addition on growth and productivities was observed at high solar irradiance and temperatures between 15 – 33 oC. However, differences were identified between the three Tetraselmis strains in biofilm development, specific growth rate and lipid productivity in association with solar irradiance and temperature. Study of Tetraselmis MUR-167 was terminated after two years of outdoor cultivation due to stickiness and biofilm development on the pond walls, with a consequent decline in specific growth and productivities. Tetraselmis MUR-230 and MUR-233 showed quite similar annual specific growth and average productivities of 12 g (ash free dry weight) m-2 d-1 and 5.3±0.4 g m-2 d-1 in semi-continuous culture over a period of 365 days for biomass and lipid respectively; however MUR-233 had a higher specific growth rate and higher lipid productivity at higher temperatures in comparison with MUR-230. Further studies were carried out on Tetraselmis MUR-233 in 2 m2, 20 m2 and 200 m2 raceway ponds at a pilot plant in Karratha, West Australia. 

Comparison between Perth and Karratha showed that Tetraselmis MUR-233 had up to three times higher biomass productivities in winter and 40 % higher during summer in Karratha. Appreciable differences in specific growth during semicontinuous cultivation were observed in 2 m2 raceway ponds compared to the 20 m2 and 200 m2 ponds accompanied with a decline in biomass productivity of up to 20 % with increasing pond size. Highest biomass productivities of 30 g (ash free dry weight) m-2 d-1 and a lipid content of up to 43 % based on ash free dry weight was achieved at an optimum cell density of 60 x 104 cells .mL-1 combined with 0.4 daily dilution and CO2 addition even under hyper saline conditions. These results were obtained at 25 MJ .m-2 solar irradiance and temperatures between 15 – 31 oC. Tetraselmis MUR-230 and MUR-233 with CO2 addition and regulated pH out-competed the major contaminating organisms, the diatoms. Tetraselmis MUR-230 grew successfully with different N-sources such as ammonium chloride, urea and sodium nitrate, the highest cellular lipids obtained with urea and sodium nitrate. Cellular carbohydrates in Tetraselmis MUR-230 increased five times under N-depletion and CO2 addition. 

In summary, this study demonstrates the feasibility of outdoor large scale cultivation of the halophilic Tetraselmis strains MUR-230 and MUR-233 with a high potential as feedstock for biofuel and carbon dioxide mitigation. The sustainability is underlined by the fact that the Tetraselmis strains were able to grow in hot and dry areas using only seawater as water source.

Saline microalgae for biofuels: Outdoor culture from small-scale to pilot scale

Aims The response of plant leaf functional traits to flooding in salt marshes is not only helpful in exploring the internal correlation between leaf plasticity mechanism and photosynthetic characteristics, but also of vital significance for gaining a better understanding on the stress resistance strategies of plants in salt marsh wetlands. The aim of this study is to investigate the responses of leaf functional traits of Saussurea salsa to flooding with the changes of water-logging durations. Methods The research site was located in provincial migratory bird nature reserve in Xiao Sugan Lake, Gansu Province, China (39.22°–39.35° N, 94.45°–94.59° E). A sample belt was selected from the edge of the lakeshore to the end of the perennial tidewater line in the low-lying area along the north side of Xiao Sugan River. The duration of water-logging in the salt marsh wetland was measured base on the water level marked by the flood rise and retreat marks in Xiao Sugan Lake over the years. The sample belt was divided into 3 plots according to the water-logging duration: low flooding area (water-logging duration: 30–90 days); medium flooding area (waterlogging duration: 90–150 days); and deep flooding area (water-logging duration: 150–210 days). Six subplots (2 m × 2 m) of S. salsa were selected from each of the three plots for a total of 18 subplots. We investigated community characteristics and population traits of S. salsa, soil moisture and soil electrical conductivity (EC). Six ©植物生态学报 Chinese Journal of Plant Ecology 686 植物生态学报 Chinese Journal of Plant Ecology 2019, 43 (8): 685–696 www.plant-ecology.com plants per subplot were selected for photosynthesis and chlorophyll fluorescence measurements. Foliar samples collected from each of the six S. salsa were taken to the laboratory for measurements of leaf traits (leaf area, thickness, dry mass and chlorophyll content). Important findings The results showed that S. salsa changed the covariation strategy of S. salsa foliar morphology and photosynthesis with the extension of water-logging duration. In the low flooding area, S. salsa adopted fleshy lobular pattern with small specific leaf area (SLA), high effective quantum yield of photosynthetic system II (PSII) photochemistry in light (Y(II)) and low quantum yield of regulated energy dissipation (Y(NPQ)). However, S. salsa grew in the deep flooding area adopted completely opposite covariation strategy in foliar morphology and photosynthesis compared with those grew in the low flooding area. We observed a significant correlation between SLA and Y(II), photochemical quenching (QP), and Y(NPQ), as well as a significant positive correlation between the quantum yield of non-regulated energy dissipation (Y(NO)) and chlorophyll a content (Ca), chlorophyll b content (Cb) in all of the three plots. Under the influence of the spatio-temporal evolution pattern of still water in the flooded area of Xiao Sugan Lake, S. salsa population achieved the balance of the photosynthetic carbon budget by changing the morphological characteristics of leaves, such as leaf area, leaf thickness and SLA, timely adjusting the photosynthetic characteristics, such as Y(NPQ) and Y(II). Saussurea salsa showed strong tolerance to water and salt heterogeneity, reflecting the leaf plasticity and resistance mechanism of salt marsh wetland plant under extreme environments.

Morphological and photosynthetic physiological characteristics of Saussurea salsa in response to flooding in salt marshes of Xiao Sugan Lake, Gansu, China

Preliminary heating of 15-16-day-old wheat (Triticum aestivum L.) plants for 3 h at 37–38°C (heat shock, HS) increased the tolerance of photosynthetic electron transport (determined as the reduction of 2,6-dichlorophenol indophenol by isolated chloroplasts) toward heating of leaves at 42–48°C in high light (100 klx). At the same time, HS did not affect the activity of the xanthophyll cycle reactions in the 30–48°C temperature range. HS exposure induced an increase in the thylakoid length, the number of grana, and the average number of thylakoids per granum. The volume of the thylakoid system increased 1.4-fold. Such indices as the total content of chlorophylls (a + b), the chlorophyll a/b ratio, as well as the contents of individual carotenoids, chloroplast membrane proteins, and the soluble leaf proteins remained unchanged. The de novo photosynthetic membrane formation was accompanied by the 1.5-fold increase in major chloroplast lipids. It was concluded that, in mature wheat chloroplasts, HS induced the formation of thylakoids characterized by a changed molecular structure and by increased lipid/protein and lipid/chlorophyll ratios.

Heat shock increases thermotolerance of photosynthetic electron transport and the content of chloroplast membranes and lipids in wheat leaves

Polyploidy is an important evolutionary force in plants and may have significant impact on plant breeding. In this study, expression changes between diploid and tetraploid Dioscorea zingiberensis C. H. under control and high temperature conditions were investigated by sequence-related amplified polymorphism (SRAP)-cDNA display approach. Up to 2.7% of the expression changes induced by genome doubling were detected in the tetraploid D. zingiberensis relative to its diploid progenitor. Under high temperature stress, a “random transcriptome response” pattern employed with 6.3% of the expression changes were detected in diploid plants, while, an “activation transcriptome response” pattern developed with 6.9% expression changes were detected in tetraploid plants. This result indicated that there might be ploidy dependent pattern of transcriptomic response to high temperature environment, which might contribute to the evolutionary success of polyploids.

/pdf/different-patterns-of-transcriptomic-response-to-high-2r9ufx60ax.pdf

Different patterns of transcriptomic response to high temperature between diploid and tetraploid Dioscorea zingiberensis C. H.

High irradiance (HI) and high temperature (HT) increased in chloroplasts the content of monogalactosyldiacylglycerol (MGDG) and decreased the contents of digalactosyldiacylglycerol (DGDG), sulfoquinovosyldiacylglycerol (SQDG), and phosphatidylinositol (PI). HI and HT accelerated the transformation of DGDG to MGDG. The contents of unsaturated fatty acids in chloroplasts increased, while those of saturated fatty acids decreased. The contents of total carotenoids, neoxanthin, violaxanthin, lutein, and β-carotene increased first, then decreased. The content of chlorophyll decreased. HI caused the unfolding of thylakoids that was not resumed after a 72-h recovery.

Effect of high irradiance and high temperature on chloroplast composition and structure of Dioscorea zingiberensis

At present, there is little research on the impact of small hydropower stations on aquatic biodiversity. In order to investigate whether the existence of small hydropower stations has a significant impact on the aquatic biodiversity of their watersheds, we conducted a systematic study on the abundance of plankton, benthic animal, fish and microorganism in the watersheds of 15 small hydropower stations in Qionglai City. The results showed that 59 species of phytoplankton from 3 divisions, 16 species of zooplankton from 4 categories, 25 species of benthic animal from 3 phyla and 30 species of fish were found in the study basin. The analysis of the physical and chemical indicators of water bodies and the distribution characteristics of aquatic organisms found that the operation of small diversion-type power stations in Qionglai City changed part of the aquatic habitat in the basin, with a greater impact on the activities of large aquatic animals (fish) and a smaller impact on plankton and microorganism, and the intensity of the impact was shown as fish > benthic animal > plankton > microorganism. The small hydropower stations in this study have an impact but not significant on the aquatic biodiversity in the Baimo and Wenjing River in the Qionglai City, and this study provides a data reference for the comprehensive assessment of the environmental impact of small hydropower stations.

https://www.frontiersin.org/articles/10.3389/fevo.2022.940606/pdf

Effects of Small Hydropower Stations Along Rivers on the Distribution of Aquatic Biodiversity

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

F. Y. Liao

Author Tools

Chat about Author

Papers

Effect of high irradiance and high temperature on chloroplast composition and structure of Dioscorea zingiberensis

Effects of Small Hydropower Stations Along Rivers on the Distribution of Aquatic Biodiversity