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BACKGROUND: Water stress seriously affects the survival of plants in natural ecosystems. Plant resistance to water stress relies on adaptive strategies, which are mainly based on plant anatomy with following relevant functions: (1) increase in water uptake and storage; (2) reduction of water loss; and (3) mechanical reinforcement of tissues. We measured 15 leaf-stem anatomical traits of five dominant shrub species from 12 community plots in the eastern Qaidam Basin to explore adaptive strategies based on plant leaf-stem anatomy at species and community levels. and their relationship with environmental stresses were tested. RESULTS: Results showed that the combination of leaf-stem anatomical traits formed three types of adaptive strategies with the drought tolerance of leaf and stem taken as two coordinate axes. Three types of water stress were caused by environmental factors in the eastern Qaidam Basin, and the established adaptive strategy triangle could be well explained by these environmental stresses. The interpretation of the strategic triangle was as follows: (1) exploitative plant strategy, in which leaf and stem adopt the hydraulic efficiency strategy and safety strategy, respectively. This strategy is mostly applied to plants in sandy desert (i.e., Nitraria tangutorum, and Artemisia sphaerocephala) which is mainly influenced by drought stress; (2) stable plant strategy, in which both leaf/assimilation branches and stem adopt hydraulic safety strategy. This strategy is mostly applied to plants in salty desert (i.e., Kalidium foliatum and Haloxylon ammodendron) which aridity has little effect on them; and (3) opportunistic plant strategy, in which leaf and stem adopt hydraulic safety strategy and water transport efficiency strategy. This strategy is mostly applied to plants in multiple habitats (i.e., Sympegma regelii) which is mainly affected by coldness stress. CONCLUSION: The proposed adaptive strategy system could provide a basis for elucidating the ecological adaptation mechanism of desert woody plants and the scientific management of natural vegetation in the Qinghai-Tibet Plateau.
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Adaptação Fisiológica , Folhas de Planta , Caules de Planta , Folhas de Planta/anatomia & histologia , Folhas de Planta/fisiologia , Caules de Planta/anatomia & histologia , Caules de Planta/fisiologia , Secas , Água/metabolismo , China , Ecossistema , Estresse FisiológicoRESUMO
BACKGROUND AND AIMS: Desiccation tolerance (DT) is crucial for survival in arid environments, where organisms develop strategies in reproduction, maintenance and defence to cope with water scarcity. Therefore, investigating the relationship between reproduction and DT is essential to understand the ecology and adaptive strategies of species. This study explores the connection between the development of male and female gametangia in the moss Bryum argenteum and the decrease in DT during the progression of phenological phases in gametangia and protonema. METHODS: Samples collected from a dry tropical forest in Brazil were cultivated, cloned and subjected to desiccation. Subsequently, the physiological parameters of shoots and protonemata were analysed. Shoot and protonema regeneration were monitored for 28 d after the physiological analyses. Both phases were subjected to control and desiccation treatments. KEY RESULTS: Significant effects of desiccation and sex on the physiological parameters and regeneration capacity of shoots and protonemata were found. Male shoots generally exhibited lower values of Fv/Fm (quantum efficiency of photosystem II) and ÏPSII (effective quantum yield of photosystem II), while females demonstrated higher values and better recovery after desiccation. Protonemata also showed variation in Fv/Fm over time and with sex, with no significant differences in ÏPSII between them. Desiccated male shoots had higher mortality rates and produced fewer new shoots. For females, the regeneration patterns varied between the desiccation-exposed groups and the control, with decreased shoot production, and some protonemata growing into filaments without forming shoots. CONCLUSION: These findings improve our understanding of the ecological responses of bryophytes to desiccation stress and provide insights into their adaptive strategies in challenging environments, such as the possible rarity of males in dioicous moss populations.
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Dessecação , Adaptação Fisiológica/fisiologia , Brotos de Planta/fisiologia , Brotos de Planta/crescimento & desenvolvimento , Bryopsida/fisiologia , Reprodução/fisiologia , BrasilRESUMO
INTRODUCTION: Developing realistic expectations of future old age constitutes an adaptational process which facilitates the anticipation of and adjustment to challenges, such as relocation to a nursing home. Developing such expectations might minimize the negative impacts of relocation. This pre-registered study examined (1) to which extent lower levels and declines in health (i.e., functional limitations and self-rated health) and life satisfaction before relocation were associated with higher levels and increases in expectations to relocate and (2) to which extent higher expectations to relocate were associated with more positive changes in health and life satisfaction after relocation. METHODS: Using data from the Health and Retirement Study (HRS; 2006-2018), we selected older adults (aged 65 years and older) who relocated to a nursing home. We used latent growth curve models to assess the longitudinal links between self-reported measures of health, life satisfaction, and expectations to relocate to a nursing home from up to 7 years before (n = 1,048) until up to 5 years after relocation (n = 307). RESULTS: As hypothesized, more functional limitations and lower self-rated health were related to higher expectations of relocation. Surprisingly, changes in expectations to relocate were not related to changes in health and life satisfaction before relocation. Moreover, expectations to relocate were not associated with changes in health and life satisfaction after relocation. CONCLUSION: The absence of a link between expectations to relocate to a nursing home with changes in health and well-being suggests that these expectations did not constitute adaptational processes before or after this transition.
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The agile remote sensing satellite scheduling problem (ARSSSP) for large-scale tasks needs to simultaneously address the difficulties of complex constraints and a huge solution space. Taking inspiration from the quantum genetic algorithm (QGA), a multi-adaptive strategies-based higher-order quantum genetic algorithm (MAS-HOQGA) is proposed for solving the agile remote sensing satellites scheduling problem in this paper. In order to adapt to the requirements of engineering applications, this study combines the total task number and the total task priority as the optimization goal of the scheduling scheme. Firstly, we comprehensively considered the time-dependent characteristics of agile remote sensing satellites, attitude maneuverability, energy balance, and data storage constraints and established a satellite scheduling model that integrates multiple constraints. Then, quantum register operators, adaptive evolution operations, and adaptive mutation transfer operations were introduced to ensure global optimization while reducing time consumption. Finally, this paper demonstrated, through computational experiments, that the MAS-HOQGA exhibits high computational efficiency and excellent global optimization ability in the scheduling process of agile remote sensing satellites for large-scale tasks, while effectively avoiding the problem that the traditional QGA has, namely low solution efficiency and the tendency to easily fall into local optima. This method can be considered for application to the engineering practice of agile remote sensing satellite scheduling for large-scale tasks.
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Many emerging invasive weeds display rapid adaptation against different stressful environments compared to their natives. Rapid adaptation and dispersal habits helped invasive populations have strong diversity within the population compared to their natives. Advances in molecular marker techniques may lead to an in-depth understanding of the genetic diversity of invasive weeds. The use of molecular techniques is rapidly growing, and their implications in invasive weed studies are considered powerful tools for genome purposes. Here, we review different approach used multi-omics by invasive weed studies to understand the functional structural and genomic changes in these species under different environmental fluctuations, particularly, to check the accessibility of advance-sequencing techniques used by researchers in genome sequence projects. In this review-based study, we also examine the importance and efficiency of different molecular techniques in identifying and characterizing different genes, associated markers, proteins, metabolites, and key metabolic pathways in invasive and native weeds. Use of these techniques could help weed scientists to further reduce the knowledge gaps in understanding invasive weeds traits. Although these techniques can provide robust insights about the molecular functioning, employing a single omics platform can rarely elucidate the gene-level regulation and the associated real-time expression of weedy traits due to the complex and overlapping nature of biological interactions. We conclude that different multi-omic techniques will provide long-term benefits in launching new genome projects to enhance the understanding of invasive weeds' invasion process.
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Genômica , Plantas Daninhas , Plantas Daninhas/genética , Fenótipo , Adaptação FisiológicaRESUMO
IMPORTANCE: The hyperarid Dalangtan Playa in the western Qaidam Basin, northwestern China, is a unique terrestrial analog of Mars. Despite the polyextreme environments of this area, habitats below translucent rocks capable of environmental buffering could serve as refuges for microbial life. In this study, the hybrid assembly of Illumina short reads and Nanopore long reads recovered high-quality and high-continuity genomes, allowing for high-accuracy analysis and a deeper understanding of extremophiles in the sheltered soils of the Dalangtan Playa. Our findings reveal self-supporting and metabolically versatile sheltered soil communities adapted to a hyperarid and hypersaline playa, which provides implications for the search for life signals on Mars.
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Microbiota , Solo , China , Microbiologia do Solo , Clima DesérticoRESUMO
The greasyback shrimp, Metapenaeus ensis, suffers from ammonia-N stress during intensive factory aquaculture. Optimizing ammonia-N stress tolerance has become an important issue in M. ensis breeding. The metabolic and adaptive mechanisms of ammonia-N toxicity in M. ensis have not been comprehensively understood yet. In this study, a large number of potential simple sequence repeats (SSRs) in the transcriptome of M. ensis were identified. Differentially expressed genes (DEGs) in the gill and hepatopancreas at 24 h post-challenges under high concentrations of ammonia-N treatment were detected. We obtained 20,108,851-27,681,918 clean reads from the control and high groups, assembled and clustered a total of 103,174 unigenes with an average of 876 bp and an N50 of 1189 bp. Comparative transcriptome analyses identified 2000 different expressed genes in the gill and 2010 different expressed genes in the hepatopancreas, a large number of which were related to immune function, oxidative stress, metabolic regulation, and apoptosis. The results suggest that M. ensis may counteract ammonia-N toxicity at the transcriptome level by increasing the expression of genes related to immune stress and detoxification metabolism, and that selected genes may serve as molecular indicators of ammonia-N. By exploring the genetic basis of M. ensis' ammonia-N stress adaptation, we constructed the genetic networks for ammonia-N adaptation. These findings will accelerate the understanding of M. ensis' ammonia-N adaptation, contribute to the research of future breeding, and promote the level of factory aquaculture of M. ensis.
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Penaeidae , Animais , Amônia/toxicidade , Amônia/metabolismo , Brânquias , Perfilação da Expressão Gênica , TranscriptomaRESUMO
Water salinity, pH, and nitrite concentration are considered environmental factors affecting the growth rate, survival, health, and physiological conditions of aquatic animals. The identification of key genes that are involved in the response to environmental stressors is essential for controlling stress in aquatic animals and sustainable aquaculture. In this study, RNA sequencing was performed to identify the differentially expressed genes (DEGs) and biological pathways that are involved in the response of the hepatopancreas to environmental stressors, including low salinity stress, nitrite stress, low pH stress, and high pH stress. The DEGs were enriched in biological pathways related to immune response, energy metabolism, oxidative stress response, hemostasis, and enzymatic activity of the hepatopancreas. In addition to the identification of DEGs related to each stressor, some DEGs were found to be expressed among all groups. The most important overlapping DEGs under multiple stressors were juvenile hormone esterase-like protein 2 (JHE-like), myosin light chain, C-type lectin 2, myosin-9-like, anti-lipopolysaccharide factor 1 (ALF-1), peroxisomal acyl-coenzyme An oxidase 1-like (ACX1), hepatic lectin-like, venom phosphodiesterase 2-like, hemolymph clottable protein-like (CP), cathepsin L, and Ras-like protein 2. The results of the present study provide additional information regarding the transcriptional response of the hepatopancreas to low salinity, nitrite, low pH, and high pH stress. Moreover, the discovery of several overlapping DEGs among different stressors provided a better understanding of the molecular function of the hepatopancreas.
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Penaeidae , Transcriptoma , Animais , Estresse Fisiológico/genética , Nitritos/metabolismo , Estresse Oxidativo , Hepatopâncreas/metabolismoRESUMO
AIMS: Studies examining the use of specific emotion regulation (ER) strategies in patients with severe alcohol use disorder (AUD) are mainly focused on intergroup comparisons to the detriment of intragroup variability. Yet, these patients are in fact characterized by emotional deficits of varying severity, and we seek to identify different patterns of ER strategies in people with AUD during their first year of abstinence. METHODS: Based on the ER strategies used by a large sample of patients with AUD, we applied cluster analysis to identify the existence of subgroups using distinct patterns of adaptive and nonadaptive strategies. To characterize these groups, we compared their clinical characteristics and then their emotional regulation strategies to those of control consumers. RESULTS: A first cluster, representing 61% of the sample, is constituted by individuals with high adaptive strategy scores and high nonadaptive strategy scores; a second cluster, representing 39% of the sample, corresponds to individuals with low adaptive strategy scores and high nonadaptive strategy scores. The individuals in these two clusters differed in terms of anxiety level and abstinence time. Compared with control consumers, the use of nonadaptive ER strategies remained lower for the two clusters, while the use of adaptative strategies differed. CONCLUSIONS: Our results support the idea of considering the heterogeneity of emotional capacities in individuals with AUD during the first year of abstinence. The identification of these profiles suggests either the existence of different adaptive ER capacities at baseline or a specific recovery of adaptive strategies over this period.
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Alcoolismo , Regulação Emocional , Humanos , Alcoolismo/psicologia , Emoções/fisiologia , Consumo de Bebidas Alcoólicas , Análise por Conglomerados , Abstinência de ÁlcoolRESUMO
The water lily (Nymphaea tetragona) is an ancient angiosperm that belongs to the Nymphaeaceae family. As a rooted floating-leaf plant, water lilies are generally cultivated in fresh water, therefore, little is known about their survival strategies under salt stress. Long-term salt stress causes morphological changes, such as the rapid regeneration of floating leaves and a significant decrease in leaf number and surface area. We demonstrate that salt stress induces toxicity soon after treatment, but plants can adapt by regenerating floating leaves that are photosynthetically active. Transcriptome profiling revealed that ion binding was one of the most-enriched GO terms in leaf-petiole systems under salt stress. Sodium-transporter-related genes were downregulated, whereas K+ transporter genes were both up- and downregulated. These results suggest that restricting intracellular Na+ importing while maintaining balanced K+ homeostasis is an adaptive strategy for tolerating long-term salt stress. ICP-MS analysis identified the petioles and leaves as Na-hyperaccumulators, with a maximum content of over 80 g kg-1 DW under salt stress. Mapping of the Na-hyperaccumulation trait onto the phylogenetic relationships revealed that water lily plants might have a long evolutionary history from ancient marine plants, or may have undergone historical ecological events from salt to fresh water. Ammonium transporter genes involved in nitrogen metabolism were downregulated, whereas NO3--related transporters were upregulated in both the leaves and petioles, suggesting a selective bias toward NO3- uptake under salt stress. The morphological changes we observed may be due to the reduced expression of genes related to auxin signal transduction. In conclusion, the floating leaves and submerged petioles of the water lily use a series of adaptive strategies to survive salt stress. These include the absorption and transport of ions and nutrients from the surrounding environments, and the ability to hyperaccumulate Na+. These adaptations may serve as the physiological basis for salt tolerance in water lily plants.
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Nymphaea , Filogenia , Estresse Salino , Folhas de Planta/metabolismo , Tolerância ao Sal/genética , Regulação da Expressão Gênica de Plantas , Estresse FisiológicoRESUMO
The aim of this study was to gain a better understanding of how Tulipa luanica adapts to growth in soil with higher concentrations of heavy metals and to assess potential toxic effects using various biomarkers, in comparison to Tulipa kosovarica, a typical serpentine species. For this purpose, we analyzed the concentrations of Al, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, and Zn in the soil, as well as their accumulation in plants and their associated stress effects. The results indicate that, despite the presence of some metals in very high concentrations in the soil (Al, Fe, Mn, and Ni), they are translocated in minimal amounts within plant organs, particularly in T. luanica. Nearly all metals exhibited significantly higher concentrations in T. kosovarica when compared to T. luanica. Based on the analysis of biomarkers, it is apparent that T. luanica shows greater sensitivity to these conditions. This is evident through the decreased activity of δ-aminolevulinic acid dehydratase and levels of δ-aminolevulinic acid, malondialdehyde, and glutathione observed in T. luanica. It appears that T. luanica effectively restricts the absorption of metals in serpentine soils; however, it experiences oxidative stress induced by these metals, setting it apart from the more resilient T. kosovarica.
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Metais Pesados , Poluentes do Solo , Tulipa , Solo , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Metais Pesados/toxicidade , Metais Pesados/análise , Monitoramento Ambiental/métodosRESUMO
Withania coagulans is a valuable medicinal plant with high demand, but its wild growth and local usage pose a threat to its natural habitat. This study aims to understand the plant's growth, anatomy, and physiology in different environmental conditions to aid in conservation and re-vegetation efforts. Fifteen differently adapted populations of Withania coagulans were collected from diverse ecological regions, viz., (i) along the roadside, (ii) hilly areas, (iii) barren land, and (iv) wasteland to unravel the adaptive mechanisms that are responsible for their ecological success across heterogenic environments of Punjab, Pakistan. The roadside populations had high values of photosynthetic pigments, total soluble proteins, root endodermis thickness, stem and leaf cortical thickness, and its cell area. The populations growing in hilly areas showed better growth performance such as vigorous growth and biomass production. Additionally, there was enhanced accumulation of organic osmolytes (glycine betaine and proline), chlorophyll content (chl a/b), and enlarged epidermal cells, cortical cells, vascular bundles, metaxylem vessels, and phloem region in roots. In case of stem area, epidermal thickness, cortical thickness, vascular bundle, and pith area showed improved growth. However, the barren land population showed significant increase in carotenoid contents, vascular bundle area, and metaxylem area in roots, and xylem vessels and phloem area in stems and leaves. The wasteland population surpassed the rest of the populations in having greater root dry weight, higher shoot ionic contents, increased root area, thick cortical, and vascular bundle area in roots. Likewise, cortical thickness and its cell area, and pith area in stems, whereas large vascular bundles, phloem region, and high stomatal density were recorded in leaves. Subsequently, natural populations showed the utmost behavior related to tissue organization and physiology in response to varied environmental conditions that would increase the distribution and survival of species.
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Plantas Medicinais , Withania , Animais , Withania/metabolismo , Espécies em Perigo de Extinção , Monitoramento Ambiental , Clorofila/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismoRESUMO
The countries along the Belt and Road (B&R) are characterized by fragile ecosystems and underdevelopment economy. International trade usually transferred the eco-environmental negative impacts to developing countries. How to avoid the conflict between economic development and eco-environmental protection is the primary concern of building the Green Silk Road. To discover the adaptive strategies for ensuring the sustainability of the social-ecosystem in countries along the B&R, this study analyzes the supply-consumption relationship of ecological resources by simulating the flow of net primary productivity between the ecosystem and the social system. The results show that: (1) The flow of ecological resources between agricultural and husbandry systems have effectively alleviated the local ecological pressure caused by animal husbandry in countries along the B&R. Animal husbandry in developed countries economize the local ecological resources by importing feed, while mitigating the grazing pressure by utilizing the local crop residues in underdeveloped agricultural countries. (2) International trade not only enables countries with insufficient ecological resources to meet their demands by importing ecological products and thus alleviate ecosystem pressure, but also promotes countries with sufficient ecological resources to transform their resource advantages into economic advantages by exporting without at the expense of ecological sustainability. (3) For underdeveloped countries, the dependence of economic development on ecological resources is at the expense of the living demands of residents, only if the economy could have leap-forward improvement the allocation of ecological resources within the social system would be inclined to living demands. These adaptive approaches not only provide the evidences of ecological-social sustainable development by promoting the reasonable flow and allocation of ecological resources, but also imply the necessary assistance for the underdeveloped countries to guarantee the basic human well-being in economic development.
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Dispersal is a critical, but costly, stage of life. During the active phase of dispersal-called transience-individuals face many costs, from increased mortality to reduced foraging opportunities. One cost that is often assumed, but rarely explicitly tested, is the energy expended in making large dispersal movements. However, this cost is not only determined by the distance individual's move, but also how they move. Using high-resolution GPS tracking of dispersing and resident vulturine guineafowl (Acryllium vulturinum), we show that transient individuals exhibit distinct movement behaviours-travelling farther, faster and straighter-that result in a significant reduction in the energetic costs of making large displacements. This strategy allows dispersing birds to travel, on average, 33.8% farther each day with only a 4.1% cost increase and without spending more time moving. Our study suggests that adaptive movement strategies can largely mitigate movement costs during dispersal, and that such strategies may be common.
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Movimento , HumanosRESUMO
BACKGROUND: Understanding the ecological strategies of urban trees to the urban environment is crucial to the selection and management of urban trees. However, it is still unclear whether urban tree pit cover will affect plant functional traits. Here, we study the response of urban trees to different tree pit covers, analyzed the effects of different cover types on soil properties and their trade-off strategies based on leaf functional traits. RESULTS: We found that there were obvious differences in the physical properties of the soil in different tree pit covers. Under the different tree pit cover types, soil bulk density and soil porosity reached the maximum under cement cover and turf cover, respectively. We found that tree pit cover significantly affected the leaf properties of urban trees. Leaf thickness, chlorophyll content index and stomatal density were mainly affected by soil bulk density and non-capillary porosity in a positive direction, and were affected by soil total porosity and capillary porosity in a negative direction. Leaf dry matter content and stomata area were mainly negatively affected by soil bulk density and non-capillary porosity, and positively affected by soil total porosity and capillary porosity. Covering materials of tree pits promoted the functional adjustment of plants and form the best combination of functions. CONCLUSION: Under the influence of tree pit cover, plant have low specific leaf area, stomata density, high leaf thickness, chlorophyll content index, leaf dry matter content, leaf tissue density and stomata area, which belong to "quick investment-return" type in the leaf economics spectrum.
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Adaptação Fisiológica , Fraxinus/crescimento & desenvolvimento , Jardinagem/métodos , Folhas de Planta/crescimento & desenvolvimento , Solo/química , Árvores/crescimento & desenvolvimento , China , Cidades , Plásticos , MadeiraRESUMO
Ammonia, one of the major limiting environment factors in aquaculture, may pose a threat to the shrimp growth, reproduction and survival. In this study, to understand molecular differences of transcriptomic and metabolomic responses and investigate the tolerance mechanisms underlying ammonia stress in Litopenaeus vannamei, ammonia-tolerant family (LV-AT) and ammonia-sensitive family (LV-AS) of these two extreme families were exposed to high-concentration (NH4Cl, 46â¯mg/L) ammonia for 24â¯h. The comparative transcriptome analysis between ammonia-treated and control (LV-C) groups revealed involvement of immune defense, cytoskeleton remodeling, antioxidative system and metabolic pathway in ammonia-stress response of L. vannamei. Likewise, metabolomics analysis showed that ammonia exposure could disturb amino acid metabolism, nucleotide metabolism and lipid metabolism, with metabolism related-genes changed according to RNA-seq analysis. The comparison of metabolite and transcript profiles between LV-AT and LV-AS indicated that LV-AT used the enhanced glycolysis and tricarboxylic acid (TCA) cycle strategies for energy supply and ammonia excretion to adapt high-concentration ammonia. Furthermore, some of genes involved in the detoxification and ammonia excretion were highly expressed in LV-AT. We speculate that the higher ability of ammonia excretion and detoxification and the accelerated energy metabolism for energy supplies might be the adaptive strategies for LV-AT relative to LV-AS after ammonia stress. Collectively, the combination of transcriptomics and metabolomics results will greatly contribute to incrementally understand the stress responses on ammonia exposure to L. vannamei and supply molecular level support for evaluating the environmental effects of ammonia on aquatic organisms. The results further constitute new sights on the potential molecular mechanisms of ammonia adaptive strategies in shrimps at the transcriptomics and metabolomics levels.
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Amônia/toxicidade , Metabolismo Energético/efeitos dos fármacos , Penaeidae/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Tolerância a Medicamentos , Perfilação da Expressão Gênica , Metabolômica , Penaeidae/genética , Penaeidae/metabolismoRESUMO
Climate change has far-reaching impacts on ecosystems. Recent attempts to quantify such impacts focus on measuring exposure to climate change but largely ignore ecosystem resistance and resilience, which may also affect the vulnerability outcomes. In this study, the relative vulnerability of global terrestrial ecosystems to short-term climate variability was assessed by simultaneously integrating exposure, sensitivity, and resilience at a high spatial resolution (0.05°). The results show that vulnerable areas are currently distributed primarily in plains. Responses to climate change vary among ecosystems and deserts and xeric shrublands are the most vulnerable biomes. Global vulnerability patterns are determined largely by exposure, while ecosystem sensitivity and resilience may exacerbate or alleviate external climate pressures at local scales; there is a highly significant negative correlation between exposure and sensitivity. Globally, 61.31% of the terrestrial vegetated area is capable of mitigating climate change impacts and those areas are concentrated in polar regions, boreal forests, tropical rainforests, and intact forests. Under current sensitivity and resilience conditions, vulnerable areas are projected to develop in high Northern Hemisphere latitudes in the future. The results suggest that integrating all three aspects of vulnerability (exposure, sensitivity, and resilience) may offer more comprehensive and spatially explicit adaptation strategies to reduce the impacts of climate change on terrestrial ecosystems.
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Mudança Climática , Ecossistema , Aclimatação , FlorestasRESUMO
Mangrove ecosystems are vulnerable to environmental threats. In order to elucidate the effect of phosphorus (P) on cadmium (Cd) tolerance and physiological responses in mangroves under Cd stress, a mangrove specie with salt exclusion Kandelia obovata and a specie with salt secretion Avicennia marina were compared in a hydroponic experiment. The results showed that most Cd was accumulated in mangrove roots and that P addition induced Cd immobilisation in them. Cd stress significantly increased malonaldehyde content, whereas P significantly decreased malonaldehyde in mangroves. Phosphorus positively regulated the photosynthetic pigment, proline content and synthesis of non-protein thiols, glutathione and phytochelatins in the leaves under Cd stress conditions. The results suggest different adaptive strategies adopted by two mangroves in a complex environment and A. marina showed a stronger Cd tolerance than K. obovata. The study provides a theoretical basis for P mediated detoxification of Cd in mangrove plants.
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Avicennia/efeitos dos fármacos , Cádmio/metabolismo , Fósforo/farmacologia , Rhizophoraceae/efeitos dos fármacos , Plântula/metabolismo , Avicennia/metabolismo , Biodegradação Ambiental , Cádmio/toxicidade , Clorofila/metabolismo , Glutationa/metabolismo , Malondialdeído/metabolismo , Fitoquelatinas/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Prolina/metabolismo , Rhizophoraceae/metabolismo , Plântula/efeitos dos fármacos , Áreas AlagadasRESUMO
Environmental heterogeneity constitutes an evolutionary challenge for organisms. While evolutionary dynamics under variable conditions has been explored for decades, we still know relatively little about the cellular and molecular mechanisms involved. It is of paramount importance to examine these molecular bases because they may play an important role in shaping the course of evolution. In this review, we examine the diversity of adaptive mechanisms in the face of environmental changes. We exploit the recent literature on microbial systems because those have benefited the most from the recent emergence of genetic engineering and experimental evolution followed by genome sequencing. We identify four emerging trends: (i) an adaptive molecular change in a pathway often results in fitness trade-off in alternative environments but the effects are dependent on a mutation's genetic background; (ii) adaptive changes often modify transcriptional and signalling pathways; (iii) several adaptive changes may occur within the same molecular pathway but be associated with pleiotropy of different signs across environments; (iv) because of their large associated costs, macromolecular changes such as gene amplification and aneuploidy may be a rapid mechanism of adaptation in the short-term only. The course of adaptation in a variable environment, therefore, depends on the complexity of the environment but also on the molecular relationships among the genes involved and between the genes and the phenotypes under selection.
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Adaptação Fisiológica , Bactérias/genética , Meio Ambiente , Evolução Molecular , Fungos/genética , Mutação , FenótipoRESUMO
Global environmental change (GEC) is an increasingly discussed phenomenon in the scientific literature as evidence of its presence and impacts continues to grow. Yet, while the documentation of GEC is becoming more readily available, local perceptions of GEC- particularly in small-scale societies-and preferences about how to deal with it, are still largely overlooked. Local knowledge and perceptions of GEC are important in that agents make decisions (including on natural resource management) based on individual perceptions. We carried out a systematic literature review that aims to provide an exhaustive state-of-the-art of the degree to and manner in which the study of local perceptions of change are being addressed in GEC research. We reviewed 126 articles found in peer-reviewed journals (between 1998 and 2014) that address local perceptions of GEC. We used three particular lenses of analysis that are known to influence local perceptions, namely (i) cognition, (ii) culture and knowledge, and (iii) possibilities for adaptation.We present our findings on the geographical distribution of the current research, the most common changes reported, perceived drivers and impacts of change, and local explanations and evaluations of change and impacts. Overall, we found the studies to be geographically biased, lacking methodological reporting, mostly theory based with little primary data, and lacking of indepth analysis of the psychological and ontological influences in perception and implications for adaptation. We provide recommendations for future GEC research and propose the development of a "meta-language" around adaptation, perception, and mediation to encourage a greater appreciation and understanding of the diversity around these phenomena across multiple scales, and improved codesign and facilitation of locally relevant adaptation and mitigation strategies.