Artificial Ecosystem

14,000,000 Leading Edge Experts on the ideXlab platform

Scan Science and Technology

Contact Leading Edge Experts & Companies

Scan Science and Technology

Contact Leading Edge Experts & Companies

The Experts below are selected from a list of 12855 Experts worldwide ranked by ideXlab platform

Hong Liu - One of the best experts on this subject based on the ideXlab platform.

  • Effect of solid waste fermentation substrate on wheat (Triticum aestivum L.) growth in closed Artificial Ecosystem
    Life sciences in space research, 2020
    Co-Authors: Dianlei Liu, Beizhen Xie, Hui Liu, Yao Zhikai, Hong Liu
    Abstract:

    Abstract Bioregenerative Life Support System (BLSS) is a closed Artificial Ecosystem and could provide oxygen, food, water and other substrates for long-term deep space survival. The treatment and recycle of the solid waste are crucial and rate-limiting steps in BLSS, and it's reported that the solid waste such as the inedible plants and human feces could be fermented aerobically and then reused as fertilizer for growing plants in BLSS, which may be an effective way to improve the solid waste recycling rate. However, the recycling performance and the effect on the system need to be evaluated. In this study, the fermented and decomposed solid waste product from the 365d BLSS experiment with human involved in Lunar Palace 1 was utilized, and was added to the Hoagland nutrient solution as a supplementary fertilizer in the weight proportion of 5% and 10%, respectively, for the cultivation of wheat (Group-5% and Group-10%). Then, the effects on wheat germination, morphology, photosynthesis, biomass, the conductivity of the cultured substrates and microorganisms were detected and compared with those of the CK group cultured using only Hoagland nutrient solution. The results showed that this planting method had no inhibitory effect on the wheat germination, root length and yield, and might even promote the vegetative growth of wheat in terms of Vigor index, plant height, leaf area and net photosynthesis rate to some extent. The added solid waste fermentation substrate as well as the planting environment in Lunar Palace 1 both had significant influences on the rhizosphere microorganisms of wheat. The bacteria diversity was more abundant than fungi at phylum level, and the relative abundance varied along with the wheat growth period. The relative abundance of the cellulose degrading microorganisms including Actinobacteria and Ascomycota increased in Group-5% and Group-10% compared with CK group along with the growth of wheat. Moreover, the proper reuse of the fermentation substrate could reduce the use of inorganic salts by 9.8%-11.9% and save 40L•m − 2 of water for wheat cultivation. This research has considerable application significance in future deep space exploration.

  • effect of different light intensity on physiology antioxidant capacity and photosynthetic characteristics on wheat seedlings under high co2 concentration in a closed Artificial Ecosystem
    Photosynthesis Research, 2020
    Co-Authors: Jingjing Cui, Hong Liu
    Abstract:

    The growth of plants under high carbon dioxide (CO2) concentrations (≥ 1000 ppm) is explored for the climate change and the bioregenerative life support system (BLSS) environment of long-duration space missions. Wheat (Triticum aestivum L.) is a grass cultivated for cereal grain—a global staple food including astronauts. Light and CO2 are both indispensable conditions for wheat seedlings. This study provides insights on the physiology, antioxidant capacity and photosynthetic characteristics of wheat seedlings under a range of photosynthetic photon flux densities in a closed system simulating BLSS with high CO2 concentration. We found that the Fv/Fm, Fv/F0, chlorophyll content, intrinsic water use efficiencies (WUEi), membrane stability index (MSI), and malondialdehyde (MDA) of wheat seedlings grown under an intermediate light intensity of 600 μmol m−2 s−1 environment were all largest. Interestingly, the high light intensity of 1200 mol m−2 s−1 treatment group exhibits the highest net photosynthetic rate but the lowest MDA content. The stomatal conductance and F0 of high light intensity of 1000 μmol m−2 s−1 treatment group were both significantly higher than that of other groups. Our study provides basic knowledge on the wheat growth in different environments, especially in a closed Ecosystem with Artificial lights.

  • Semi-continuous fermentation of solid waste in closed Artificial Ecosystem: Microbial diversity, function genes evaluation.
    Life sciences in space research, 2019
    Co-Authors: Dianlei Liu, Beizhen Xie, Yingying Dong, Hong Liu
    Abstract:

    Abstract Bioregenerative Life Support System (BLSS) is a closed Artificial Ecosystem and could provide oxygen, food, water and other substances for space survival. Solid waste treatment is a key rate-limiting step in BLSS. In this study, solid wastes including wheat straw, human and yellow mealworm feces were disposed in a semi-continuous bio-convertor for 105 days in a ground-based experimental BLSS platform (Lunar Palace 1). Solid wastes at different periods were sampled and the microbial community variation, functional genes and metabolic pathways were analyzed. The results showed phyla Firmicutes, Bacteroidetes and Proteobacteria predominated in all samples. While microbial community structures at genus level were significantly different, indicating selective enrichment during the 105-day process. The abundance of functional gene related to carbohydrate transport and metabolism was predicted higher on 45-day and 70-day. The metabolic pathway analysis revealed the degradation mechanisms and provided evidence for metabolic regulation.

  • Shifts of microbial communities of wheat (Triticum aestivum L.) cultivation in a closed Artificial Ecosystem.
    Applied microbiology and biotechnology, 2016
    Co-Authors: Youcai Qin, Chen Dong, Nannan Jia, Hong Liu
    Abstract:

    The microbial communities of plant Ecosystems are in relation to plant growing environment, but the alteration in biodiversity of rhizosphere and phyllosphere microbial communities in closed and controlled environments is unknown. The purpose of this study is to analyze the change regularity of microbial communities with wheat plants dependent-cultivated in a closed Artificial Ecosystem. The microbial community structures in closed-environment treatment plants were investigated by a culture-dependent approach, polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), and Illumina Miseq high-throughput sequencing. The results indicated that the number of microbes decreased along with time, and the magnitude of bacteria, fungi, and actinomycetes were 10(7)-10(8), 10(5), and 10(3)-10(4) CFU/g (dry weight), respectively. The analysis of PCR-DGGE and Illumina Miseq revealed that the wheat leaf surface and near-root substrate had different microbial communities at different periods of wheat Ecosystem development and showed that the relative highest diversity of microbial communities appeared at late and middle periods of the plant Ecosystem, respectively. The results also indicated that the wheat leaf and substrate had different microbial community compositions, and the wheat substrate had higher richness of microbial community than the leaf. Flavobacterium, Pseudomonas, Paenibacillus, Enterobacter, Penicillium, Rhodotorula, Acremonium, and Alternaria were dominant in the wheat leaf samples, and Pedobacter, Flavobacterium, Halomonas, Marinobacter, Salinimicrobium, Lysobacter, Pseudomonas, Halobacillus, Xanthomonas, Acremonium, Monographella, and Penicillium were dominant populations in the wheat near-root substrate samples.

  • can closed Artificial Ecosystem have an impact on insect microbial community a case study of yellow mealworm tenebrio molitor l
    Ecological Engineering, 2016
    Co-Authors: Leyuan Li, Beizhen Xie, Chen Dong, Minjuan Wang, Hong Liu
    Abstract:

    Abstract A case study of the effects of rearing yellow mealworm ( Tenebrio molitor L.) in a closed Artificial Ecosystem on their associated microbial communities is presented. Two groups of T. molitor larvae were reared, one in a controlled environment agricultural Ecosystem and another one in an open environment (as a control). Microbial community structures of larval midgut, larval homogenate and frass samples of both groups, and a sample of feed, which was made through the fermentation of plant wastes, were tested by 16S rRNA gene sequencing on the Illumina MiSeq platform. Microbiota differences among the two groups and the feed revealed that the diversities of microbial communities in all samples of both groups decreased compared with the feed, with the lowest in midgut of the both groups. Compared with the three samples from the closed Ecosystem, those from the open environment had higher abundances of Bacillus , Lactococcus , Weissella , Escherichia and Clostridiaceae. Enterococcus and some unclassified Enterobacteriaceae were identified as the predominant bacteria in samples from the closed Ecosystem. The classes Acidobacteria, Planctomycetacia and Sphingobacteria were found in feed, but almost disappeared in the samples of both groups. Possible metabolic and immune effects of the above differences in associated microbial communities on larval growth are discussed. With the aim of improving the rearing efficiency of T. molitor in such a controlled environment agricultural Ecosystem, follow-up study would focus on microbial isolation from the midgut of T. molitor for the preparation of probiotics as well as measures of microbial pathogen control.

Christoph Hinz - One of the best experts on this subject based on the ideXlab platform.

  • transpiration and plant water relations of evergreen woody vegetation on a recently constructed Artificial Ecosystem under seasonally dry conditions in western australia
    Hydrological Processes, 2012
    Co-Authors: Willis Gwenzi, Erik J. Veneklaas, Timothy M. Bleby, Isa A. M. Yunusa, Christoph Hinz
    Abstract:

    Understanding transpiration and plant physiological responses to environmental conditions is crucial for the design and management of vegetated engineered covers. Engineered covers rely on sustained transpiration to reduce the risk of deep drainage into potentially hazardous wastes, thereby minimizing contamination of water resources. This study quantified temporal trends of plant water potential (ψp), stomatal conductance (gs), and transpiration in a 4-year-old evergreen woody vegetation growing on an Artificial sandy substrate at a mine waste disposal facility. Transpiration averaged 0.7 mm day−1 in winter, when rainfall was frequent, but declined to 0.2 mm day−1 in the dry summer, when the plants were quite stressed. In winter, the mean ψp was −0.6 MPa at predawn and −1.5 MPa at midday, which were much higher than the corresponding summer values of −2.0 MPa and −4.8 MPa, respectively. The gs was also higher in winter (72.1–95.0 mmol m−2 s−1) than in summer (<30 mmol m−2 s−1), and negatively correlated with ψp (p < 0.05, r2 = 0.71–0.75), indicating strong stomatal control of transpiration in response to moisture stress. Total annual transpiration (147.2 mm) accounted for only 22% of the annual rainfall (673 mm), compared with 77% to 99% for woody vegetation in Western Australia. The low annual transpiration was attributed to the collective effects of a sparse and young vegetation, low moisture retention of the sandy substrate, and a superficial root system constrained by high subsoil pH. Amending the substrate with fine-textured materials should improve water storage of the substrate and enhance canopy growth and deep rooting, while further reducing the risk of deep drainage during the early stages of vegetation establishment and in the long term. Overall, this study highlights the need to understand substrate properties, vegetation characteristics, and rainfall patterns when designing Artificial Ecosystems to achieve specific hydrological functions. Copyright © 2011 John Wiley & Sons, Ltd.

  • Transpiration and plant water relations of evergreen woody vegetation on a recently constructed Artificial Ecosystem under seasonally dry conditions in Western Australia
    Hydrological Processes, 2012
    Co-Authors: Willis Gwenzi, Erik J. Veneklaas, Timothy M. Bleby, Isa A. M. Yunusa, Christoph Hinz
    Abstract:

    Understanding transpiration and plant physiological responses to environmental conditions is crucial for the design and management of vegetated engineered covers. Engineered covers rely on sustained transpiration to reduce the risk of deep drainage into potentially hazardous wastes, thereby minimizing contamination of water resources. This study quantified temporal trends of plant water potential (ψp), stomatal conductance (gs), and transpiration in a 4-year-old evergreen woody vegetation growing on an Artificial sandy substrate at a mine waste disposal facility. Transpiration averaged 0.7 mm day−1 in winter, when rainfall was frequent, but declined to 0.2 mm day−1 in the dry summer, when the plants were quite stressed. In winter, the mean ψp was −0.6 MPa at predawn and −1.5 MPa at midday, which were much higher than the corresponding summer values of −2.0 MPa and −4.8 MPa, respectively. The gs was also higher in winter (72.1–95.0 mmol m−2 s−1) than in summer (

  • field scale spatial variability of saturated hydraulic conductivity on a recently constructed Artificial Ecosystem
    Geoderma, 2011
    Co-Authors: Willis Gwenzi, Christoph Hinz, Karen W Holmes, I R Phillips, Ian J Mullins
    Abstract:

    Abstract Saturated hydraulic conductivity ( K s ) influences water storage and movement, and is a key parameter of water and solute transport models. Systematic field evaluation of K s and its spatial variability for recently constructed Artificial Ecosystems is still lacking. The objectives of the present study were; (1) to determine saturated hydraulic conductivity of an Artificial Ecosystem using field methods (Philip–Dunne, and Guelph permeameters), and compare their results to the constant-head laboratory method; (2) to evaluate the spatial variability of K s using univariate and geostatistical analyses, and (3) to evaluate the ability of five pedotransfer functions to predict K s . The results showed that K s varied significantly (p  K s values were very high for all methods (38.6–77.9 m day − 1 ), exceeding values for natural sandy soils by several orders of magnitude. The high K s values and low coefficients of variation (26–44%) were comparable to that of well-sorted unconsolidated marine sands. Geostatistical analysis revealed a spatial structure in surface K s data described by a spherical model with a correlation range of 8 m. The resulting kriged map of surface K s showed alternating bands of high and low values, consistent with surface structures created by wheel tracks of construction equipment. Vertical K s was also spatially structured, with a short correlation range of 40 cm, presumably indicative of layering caused by post-construction mobilization and deposition of fine particles. K s was linearly and negatively correlated with dry soil bulk density (ρ b ) (r 2  = 0.73), and to a lesser extent silt plus clay percentage ( Si  +  C ) (r 2  = 0.21). Combining both ρ b and Si  +  C significantly (p  K s (r 2  = 0.76). However, evaluation of five PTFs developed for natural soils showed that they all underestimated K s by an order of magnitude, suggesting that application of water balance simulation models based on such PTFs to the present study site may constitute a bias in model outputs. Overall, the study demonstrated the influence of material handling, construction procedures and post-construction processes on the magnitude and spatial variability of K s on a recently constructed Artificial Ecosystem. These unique hydraulic properties may have profound impacts on soil moisture storage, plant water relations and water balance fluxes on Artificial Ecosystems, particularly where such landforms are intended to restore pre-disturbance ecological and hydrological functions.

Willis Gwenzi - One of the best experts on this subject based on the ideXlab platform.

  • transpiration and plant water relations of evergreen woody vegetation on a recently constructed Artificial Ecosystem under seasonally dry conditions in western australia
    Hydrological Processes, 2012
    Co-Authors: Willis Gwenzi, Erik J. Veneklaas, Timothy M. Bleby, Isa A. M. Yunusa, Christoph Hinz
    Abstract:

    Understanding transpiration and plant physiological responses to environmental conditions is crucial for the design and management of vegetated engineered covers. Engineered covers rely on sustained transpiration to reduce the risk of deep drainage into potentially hazardous wastes, thereby minimizing contamination of water resources. This study quantified temporal trends of plant water potential (ψp), stomatal conductance (gs), and transpiration in a 4-year-old evergreen woody vegetation growing on an Artificial sandy substrate at a mine waste disposal facility. Transpiration averaged 0.7 mm day−1 in winter, when rainfall was frequent, but declined to 0.2 mm day−1 in the dry summer, when the plants were quite stressed. In winter, the mean ψp was −0.6 MPa at predawn and −1.5 MPa at midday, which were much higher than the corresponding summer values of −2.0 MPa and −4.8 MPa, respectively. The gs was also higher in winter (72.1–95.0 mmol m−2 s−1) than in summer (<30 mmol m−2 s−1), and negatively correlated with ψp (p < 0.05, r2 = 0.71–0.75), indicating strong stomatal control of transpiration in response to moisture stress. Total annual transpiration (147.2 mm) accounted for only 22% of the annual rainfall (673 mm), compared with 77% to 99% for woody vegetation in Western Australia. The low annual transpiration was attributed to the collective effects of a sparse and young vegetation, low moisture retention of the sandy substrate, and a superficial root system constrained by high subsoil pH. Amending the substrate with fine-textured materials should improve water storage of the substrate and enhance canopy growth and deep rooting, while further reducing the risk of deep drainage during the early stages of vegetation establishment and in the long term. Overall, this study highlights the need to understand substrate properties, vegetation characteristics, and rainfall patterns when designing Artificial Ecosystems to achieve specific hydrological functions. Copyright © 2011 John Wiley & Sons, Ltd.

  • Transpiration and plant water relations of evergreen woody vegetation on a recently constructed Artificial Ecosystem under seasonally dry conditions in Western Australia
    Hydrological Processes, 2012
    Co-Authors: Willis Gwenzi, Erik J. Veneklaas, Timothy M. Bleby, Isa A. M. Yunusa, Christoph Hinz
    Abstract:

    Understanding transpiration and plant physiological responses to environmental conditions is crucial for the design and management of vegetated engineered covers. Engineered covers rely on sustained transpiration to reduce the risk of deep drainage into potentially hazardous wastes, thereby minimizing contamination of water resources. This study quantified temporal trends of plant water potential (ψp), stomatal conductance (gs), and transpiration in a 4-year-old evergreen woody vegetation growing on an Artificial sandy substrate at a mine waste disposal facility. Transpiration averaged 0.7 mm day−1 in winter, when rainfall was frequent, but declined to 0.2 mm day−1 in the dry summer, when the plants were quite stressed. In winter, the mean ψp was −0.6 MPa at predawn and −1.5 MPa at midday, which were much higher than the corresponding summer values of −2.0 MPa and −4.8 MPa, respectively. The gs was also higher in winter (72.1–95.0 mmol m−2 s−1) than in summer (

  • field scale spatial variability of saturated hydraulic conductivity on a recently constructed Artificial Ecosystem
    Geoderma, 2011
    Co-Authors: Willis Gwenzi, Christoph Hinz, Karen W Holmes, I R Phillips, Ian J Mullins
    Abstract:

    Abstract Saturated hydraulic conductivity ( K s ) influences water storage and movement, and is a key parameter of water and solute transport models. Systematic field evaluation of K s and its spatial variability for recently constructed Artificial Ecosystems is still lacking. The objectives of the present study were; (1) to determine saturated hydraulic conductivity of an Artificial Ecosystem using field methods (Philip–Dunne, and Guelph permeameters), and compare their results to the constant-head laboratory method; (2) to evaluate the spatial variability of K s using univariate and geostatistical analyses, and (3) to evaluate the ability of five pedotransfer functions to predict K s . The results showed that K s varied significantly (p  K s values were very high for all methods (38.6–77.9 m day − 1 ), exceeding values for natural sandy soils by several orders of magnitude. The high K s values and low coefficients of variation (26–44%) were comparable to that of well-sorted unconsolidated marine sands. Geostatistical analysis revealed a spatial structure in surface K s data described by a spherical model with a correlation range of 8 m. The resulting kriged map of surface K s showed alternating bands of high and low values, consistent with surface structures created by wheel tracks of construction equipment. Vertical K s was also spatially structured, with a short correlation range of 40 cm, presumably indicative of layering caused by post-construction mobilization and deposition of fine particles. K s was linearly and negatively correlated with dry soil bulk density (ρ b ) (r 2  = 0.73), and to a lesser extent silt plus clay percentage ( Si  +  C ) (r 2  = 0.21). Combining both ρ b and Si  +  C significantly (p  K s (r 2  = 0.76). However, evaluation of five PTFs developed for natural soils showed that they all underestimated K s by an order of magnitude, suggesting that application of water balance simulation models based on such PTFs to the present study site may constitute a bias in model outputs. Overall, the study demonstrated the influence of material handling, construction procedures and post-construction processes on the magnitude and spatial variability of K s on a recently constructed Artificial Ecosystem. These unique hydraulic properties may have profound impacts on soil moisture storage, plant water relations and water balance fluxes on Artificial Ecosystems, particularly where such landforms are intended to restore pre-disturbance ecological and hydrological functions.

Beizhen Xie - One of the best experts on this subject based on the ideXlab platform.

  • Effect of solid waste fermentation substrate on wheat (Triticum aestivum L.) growth in closed Artificial Ecosystem
    Life sciences in space research, 2020
    Co-Authors: Dianlei Liu, Beizhen Xie, Hui Liu, Yao Zhikai, Hong Liu
    Abstract:

    Abstract Bioregenerative Life Support System (BLSS) is a closed Artificial Ecosystem and could provide oxygen, food, water and other substrates for long-term deep space survival. The treatment and recycle of the solid waste are crucial and rate-limiting steps in BLSS, and it's reported that the solid waste such as the inedible plants and human feces could be fermented aerobically and then reused as fertilizer for growing plants in BLSS, which may be an effective way to improve the solid waste recycling rate. However, the recycling performance and the effect on the system need to be evaluated. In this study, the fermented and decomposed solid waste product from the 365d BLSS experiment with human involved in Lunar Palace 1 was utilized, and was added to the Hoagland nutrient solution as a supplementary fertilizer in the weight proportion of 5% and 10%, respectively, for the cultivation of wheat (Group-5% and Group-10%). Then, the effects on wheat germination, morphology, photosynthesis, biomass, the conductivity of the cultured substrates and microorganisms were detected and compared with those of the CK group cultured using only Hoagland nutrient solution. The results showed that this planting method had no inhibitory effect on the wheat germination, root length and yield, and might even promote the vegetative growth of wheat in terms of Vigor index, plant height, leaf area and net photosynthesis rate to some extent. The added solid waste fermentation substrate as well as the planting environment in Lunar Palace 1 both had significant influences on the rhizosphere microorganisms of wheat. The bacteria diversity was more abundant than fungi at phylum level, and the relative abundance varied along with the wheat growth period. The relative abundance of the cellulose degrading microorganisms including Actinobacteria and Ascomycota increased in Group-5% and Group-10% compared with CK group along with the growth of wheat. Moreover, the proper reuse of the fermentation substrate could reduce the use of inorganic salts by 9.8%-11.9% and save 40L•m − 2 of water for wheat cultivation. This research has considerable application significance in future deep space exploration.

  • Semi-continuous fermentation of solid waste in closed Artificial Ecosystem: Microbial diversity, function genes evaluation.
    Life sciences in space research, 2019
    Co-Authors: Dianlei Liu, Beizhen Xie, Yingying Dong, Hong Liu
    Abstract:

    Abstract Bioregenerative Life Support System (BLSS) is a closed Artificial Ecosystem and could provide oxygen, food, water and other substances for space survival. Solid waste treatment is a key rate-limiting step in BLSS. In this study, solid wastes including wheat straw, human and yellow mealworm feces were disposed in a semi-continuous bio-convertor for 105 days in a ground-based experimental BLSS platform (Lunar Palace 1). Solid wastes at different periods were sampled and the microbial community variation, functional genes and metabolic pathways were analyzed. The results showed phyla Firmicutes, Bacteroidetes and Proteobacteria predominated in all samples. While microbial community structures at genus level were significantly different, indicating selective enrichment during the 105-day process. The abundance of functional gene related to carbohydrate transport and metabolism was predicted higher on 45-day and 70-day. The metabolic pathway analysis revealed the degradation mechanisms and provided evidence for metabolic regulation.

  • can closed Artificial Ecosystem have an impact on insect microbial community a case study of yellow mealworm tenebrio molitor l
    Ecological Engineering, 2016
    Co-Authors: Leyuan Li, Beizhen Xie, Chen Dong, Minjuan Wang, Hong Liu
    Abstract:

    Abstract A case study of the effects of rearing yellow mealworm ( Tenebrio molitor L.) in a closed Artificial Ecosystem on their associated microbial communities is presented. Two groups of T. molitor larvae were reared, one in a controlled environment agricultural Ecosystem and another one in an open environment (as a control). Microbial community structures of larval midgut, larval homogenate and frass samples of both groups, and a sample of feed, which was made through the fermentation of plant wastes, were tested by 16S rRNA gene sequencing on the Illumina MiSeq platform. Microbiota differences among the two groups and the feed revealed that the diversities of microbial communities in all samples of both groups decreased compared with the feed, with the lowest in midgut of the both groups. Compared with the three samples from the closed Ecosystem, those from the open environment had higher abundances of Bacillus , Lactococcus , Weissella , Escherichia and Clostridiaceae. Enterococcus and some unclassified Enterobacteriaceae were identified as the predominant bacteria in samples from the closed Ecosystem. The classes Acidobacteria, Planctomycetacia and Sphingobacteria were found in feed, but almost disappeared in the samples of both groups. Possible metabolic and immune effects of the above differences in associated microbial communities on larval growth are discussed. With the aim of improving the rearing efficiency of T. molitor in such a controlled environment agricultural Ecosystem, follow-up study would focus on microbial isolation from the midgut of T. molitor for the preparation of probiotics as well as measures of microbial pathogen control.

  • Microbial community structure and succession of airborne microbes in closed Artificial Ecosystem
    Ecological Engineering, 2016
    Co-Authors: Yi Sun, Beizhen Xie, Chen Dong, Minjuan Wang, Du Xiaojie, Hong Liu
    Abstract:

    Abstract Microbes play a significant role in achieving substance circulation and regeneration in closed Artificial Ecosystems (CAES) such as bioregenerative life support system (BLSS), greenhouses, and aquaria. In order to understand the pattern of microbial development inside such closed systems, a ground-based closed comprehensive BLSS experimental system named “Lunar Palace 1 (LP1)” was established and a 105-day manned BLSS experiment was carried out in LP1 by our team. During this closed experiment, airborne microbes in the closed cabins of LP1 were sampled and the development and succession law of microorganisms were analyzed using both plate cultivation and molecular biology methods. The results indicated that the dominant bacteria in the air of LP1 were Cupriavidus, Afipia, Delftia, Cyanobacteria and Enterococcus and the dominant fungi were Penicillium, Alternaria, Aspergillus and Cochliobolus, which included not only ubiquitous environmental microorganisms but also opportunistic pathogens. And the succession of dominant microbes’ composition also provided an important experience for solving the problem of microbial contamination in CAES and set a solid foundation for establishing more targeted microbial prevention and control measures in long-term multi-crew closed BLSS experiments in the future.

  • Effects of different elevated CO2 concentrations on chlorophyll contents, gas exchange, water use efficiency, and PSII activity on C3 and C4 cereal crops in a closed Artificial Ecosystem.
    Photosynthesis Research, 2015
    Co-Authors: Minjuan Wang, Beizhen Xie, Chen Dong, Liu Hui, Liu Guanghui, Hong Liu
    Abstract:

    Although terrestrial CO2 concentrations [CO2] are not expected to reach 1000 μmol mol−1 (or ppm) for many decades, CO2 levels in closed systems such as growth chambers and greenhouses can easily exceed this concentration. CO2 levels in life support systems (LSS) in space can exceed 10,000 ppm (1 %). In order to understand how photosynthesis in C4 plants may respond to elevated CO2, it is necessary to determine if leaves of closed Artificial Ecosystem grown plants have a fully developed C4 photosynthetic apparatus, and whether or not photosynthesis in these leaves is more responsive to elevated [CO2] than leaves of C3 plants. To address this issue, we evaluated the response of gas exchange, water use efficiency, and photosynthetic efficiency of PSII by soybean (Glycine max (L.) Merr., ‘Heihe35’) of a typical C3 plant and maize (Zea mays L., ‘Susheng’) of C4 plant under four CO2 concentrations (500, 1000, 3000, and 5000 ppm), which were grown under controlled environmental conditions of Lunar Palace 1. The results showed that photosynthetic pigment by the C3 plants of soybean was more sensitive to elevated [CO2] below 3000 ppm than the C4 plants of maize. Elevated [CO2] to 1000 ppm induced a higher initial photosynthetic rate, while super-elevated [CO2] appeared to negate such initial growth promotion for C3 plants. The C4 plant had the highest ETR, φPSII, and qP under 500–3000 ppm [CO2], but then decreased substantially at 5000 ppm [CO2] for both species. Therefore, photosynthetic down-regulation and a decrease in photosynthetic electron transport occurred by both species in response to super-elevated [CO2] at 3000 and 5000 ppm. Accordingly, plants can be selected for and adapt to the efficient use of elevated CO2 concentration in LSS.

Peter J. Bentley - One of the best experts on this subject based on the ideXlab platform.

  • Artificial Ecosystem Algorithm Applied to Multi-Line Steel Scheduling
    2019 IEEE Congress on Evolutionary Computation (CEC), 2019
    Co-Authors: Manal T. Adham, Peter J. Bentley
    Abstract:

    Steel production scheduling is recognised as a major global industry with some of the most difficult industrial logistical problems. Galvanised steel can be used as a raw material for the automotive or construction industries. This paper focuses on scheduling four lines involved in the production of galvanised steel. Specifically, we consider lines in ArcelorMittal's manufacturing plant. ArcelorMittal is one of the largest steel producers in the world. The lines considered include the following: (a) Pickling Line, (b) Tandem Mill Line, (c) Hot Dip Galvanizing Line 1, and (d) Hot Dip Galvanizing Line 2. We apply four variants of the Artificial Ecosystem Algorithm to the multi-line steel scheduling problem. In addition, we compare their performance against several alternative solutions including Simulated Annealing, Tabu Search, Hill Climbing, Branch and Bound, Monte Carlo Tree Search, Genetic Algorithm, Cuckoo Search and Particle Swarm Optimisation.

  • CEC - Artificial Ecosystem Algorithm Applied to Multi-Line Steel Scheduling
    2019 IEEE Congress on Evolutionary Computation (CEC), 2019
    Co-Authors: Manal T. Adham, Peter J. Bentley
    Abstract:

    Steel production scheduling is recognised as a major global industry with some of the most difficult industrial logistical problems. Galvanised steel can be used as a raw material for the automotive or construction industries. This paper focuses on scheduling four lines involved in the production of galvanised steel. Specifically, we consider lines in ArcelorMittal’s manufacturing plant. ArcelorMittal is one of the largest steel producers in the world. The lines considered include the following: (a) Pickling Line, (b) Tandem Mill Line, (c) Hot Dip Galvanizing Line 1, and (d) Hot Dip Galvanizing Line 2. We apply four variants of the Artificial Ecosystem Algorithm to the multi-line steel scheduling problem. In addition, we compare their performance against several alternative solutions including Simulated Annealing, Tabu Search, Hill Climbing, Branch and Bound, Monte Carlo Tree Search, Genetic Algorithm, Cuckoo Search and Particle Swarm Optimisation.

  • Evaluating clustering methods within the Artificial Ecosystem Algorithm and their application to bike redistribution in London
    Bio Systems, 2016
    Co-Authors: Manal T. Adham, Peter J. Bentley
    Abstract:

    This paper proposes and evaluates a solution to the truck redistribution problem prominent in London's Santander Cycle scheme. Due to the complexity of this NP-hard combinatorial optimisation problem, no efficient optimisation techniques are known to solve the problem exactly. This motivates our use of the heuristic Artificial Ecosystem Algorithm (AEA) to find good solutions in a reasonable amount of time. The AEA is designed to take advantage of highly distributed computer architectures and adapt to changing problems. In the AEA a problem is first decomposed into its relative sub-components; they then evolve solution building blocks that fit together to form a single optimal solution. Three variants of the AEA centred on evaluating clustering methods are presented: the baseline AEA, the community-based AEA which groups stations according to journey flows, and the Adaptive AEA which actively modifies clusters to cater for changes in demand. We applied these AEA variants to the redistribution problem prominent in bike share schemes (BSS). The AEA variants are empirically evaluated using historical data from Santander Cycles to validate the proposed approach and prove its potential effectiveness.

  • an Artificial Ecosystem algorithm applied to the travelling salesman problem
    Genetic and Evolutionary Computation Conference, 2014
    Co-Authors: Manal T. Adham, Peter J. Bentley
    Abstract:

    An Ecosystem inspired algorithm that aims to take advantage of highly distributed computer architectures is proposed. Our motivation is to grasp the phenomenal properties of Ecosystems and use them for large-scale real-world problems. Just as an Ecosystem comprises of many separate components that adapt together to form a single synergistic whole, the Artificial Ecosystem Algorithm (AEA) solves a problem by adapting subcomponents such that they fit together and form a single optimal solution. Typical biology inspired algorithms like GA, PSO, BCO, and ACO, represent candidate solutions as individuals in a population. However, AEA uses populations of solution components that are solved individually such that they combine to form the candidate solution. Like species in an Ecosystem, AEA has different species that represent sub-parts of the solution, these species evolve and cooperate to form a complete solution.

  • GECCO (Companion) - An Artificial Ecosystem algorithm applied to the travelling salesman problem
    Proceedings of the 2014 conference companion on Genetic and evolutionary computation companion - GECCO Comp '14, 2014
    Co-Authors: Manal T. Adham, Peter J. Bentley
    Abstract:

    An Ecosystem inspired algorithm that aims to take advantage of highly distributed computer architectures is proposed. Our motivation is to grasp the phenomenal properties of Ecosystems and use them for large-scale real-world problems. Just as an Ecosystem comprises of many separate components that adapt together to form a single synergistic whole, the Artificial Ecosystem Algorithm (AEA) solves a problem by adapting subcomponents such that they fit together and form a single optimal solution. Typical biology inspired algorithms like GA, PSO, BCO, and ACO, represent candidate solutions as individuals in a population. However, AEA uses populations of solution components that are solved individually such that they combine to form the candidate solution. Like species in an Ecosystem, AEA has different species that represent sub-parts of the solution, these species evolve and cooperate to form a complete solution.