Soil conservation measures (SCM) are believed to be effective in terms of wind erosion control. Currently, most studies regarding the efficacy of SCM in erosion control are based on data of ...individual experimental sites. A comprehensive understanding of the effectiveness of SCM and related impacting factors at large scale is lacking. A synthesis was conducted in this study based on data compiled from field experiments in major eroded regions of China in order to fully evaluate the efficacy of various SCM practices in erosion reduction, and further assess how their efficacy varied under different environmental conditions. Two main SCM categories were identified, i.e. agricultural measures (AM) used for both crop production and erosion control, and vegetation measures (VM) used for erosion control only. The results showed that SCM could lead to a significant reduction of wind erosion by over a half (0.51). The reduction of wind erosion under VM (0.56) was significantly higher than AM (0.46). Specifically, most AM and all the VM investigated in this study were beneficial for wind erosion control. Multiple cropping was the only practice that significantly increased the wind erosion rate compared to the conventional treatment. We further found that the effectiveness of SCM highly dependent on precipitation, temperature, soil organic carbon concentration, soil water content, soil type, elevation, and vegetation coverage. The responses of the efficacy of AM and VM to these environmental conditions also differed. Another important finding is that the lowest efficacy of SCM in erosion control was observed in regions with the highest erosion risk, indicating the greater challenge in erosion reduction in these regions. The efficacy of SCM quantified in this study can be used as an essential reference for the adoption of SCM in China and the environmental conditions should also be considered carefully when designing a SCM application framework.
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•Agricultural measures (AM) and vegetation measures (VM) both reduce wind erosion.•Environmental conditions may determine soil conservation measures (SCM) efficacy.•The lowest efficacy of SCM is generally in regions with the highest erosion risk.
In many regions across the globe, extreme weather events such as storms have increased in frequency, intensity, and duration due to climate change. Ecological theory predicts that such extreme events ...should have large impacts on ecosystem structure and function. High winds and precipitation associated with storms can affect lakes via short‐term runoff events from watersheds and physical mixing of the water column. In addition, lakes connected to rivers and streams will also experience flushing due to high flow rates. Although we have a well‐developed understanding of how wind and precipitation events can alter lake physical processes and some aspects of biogeochemical cycling, our mechanistic understanding of the emergent responses of phytoplankton communities is poor. Here we provide a comprehensive synthesis that identifies how storms interact with lake and watershed attributes and their antecedent conditions to generate changes in lake physical and chemical environments. Such changes can restructure phytoplankton communities and their dynamics, as well as result in altered ecological function (e.g., carbon, nutrient and energy cycling) in the short‐ and long‐term. We summarize the current understanding of storm‐induced phytoplankton dynamics, identify knowledge gaps with a systematic review of the literature, and suggest future research directions across a gradient of lake types and environmental conditions.
Our understanding of ecosystem‐scale responses to storm events is fragmented, and terminological variability in defining a “storm” hinders resolution of generalizable impacts. We provide a comprehensive synthesis of the interactions between physical properties and biological responses in lakes that demonstrates the context‐dependency of storm impacts; lake/watershed attributes and their antecedent conditions mediate the extent to which storms impact lake ecosystems. We develop a framework which conceptualizes how abrupt, storm‐induced changes in the lake environment influence phytoplankton community dynamics through functional traits, identifies current limitations, and highlights several avenues of research to narrow knowledge gaps in synthetic and interdisciplinary ways.
•A framework is proposed for the quantitative causation analysis of grounding accidents in Arctic waters.•Potential risk factors are identified for grounding accidents in Arctic shipping.•The ...interdependency of the risk factors is reflected using the AcciMap model.•The critical risk factors are identified for quantitative analysis using the BN model.•RCOs are proposed for decreasing the risk of ship grounding in Arctic shipping.
The melting of Arctic Sea ice has significantly facilitated Arctic shipping. However, such increased shipping has brought about higher maritime accidents in Arctic waters, especially for grounding and fire/explosion accidents. The paper presents a framework for quantitative analysis of the causation of grounding accidents in Arctic shipping by developing an accident map (AcciMap) - Bayesian network (BN) model. First, the potential risk factors for grounding accidents in the Arctic shipping were identified according to 322 maritime accident investigation reports (MAIRs) - 299 global MAIRs of grounding accidents (including 5 in Arctic waters) and 23 MAIRs (except grounding accidents) in Arctic waters and related literature. Consequently, an AcciMap model is developed for describing the evolution of grounding accident scenarios and reflecting the interdependency of the identified risk factors. Then, a probabilistic model is proposed to evaluate the probability and severity of the grounding accident for presenting a convincing justification for risk control options (RCOs). The framework is applied for the quantitative analysis of a cruise ship grounding accident in Arctic waters. Results demonstrate (1) improved understanding of cruise ship grounding risk factors related to government supervision, shipping company management, technical and operational management, unsafe incidents and behaviors, and environmental conditions; (2) quantitative analysis of the evolution of grounding accident and better identification of the critical risk factors; (3) determination of RCOs for risk management in Arctic shipping.
The sorption of polybrominated diphenyl ethers (PBDEs) onto polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyamide (PA) microplastics was analyzed using different kinetic and isotherm ...models, and under various environmental conditions, including temperature, pH, salinity and dissolved organic matter (DOM). The sorption capacity was in the order of PS > PA > PP > PE, due to the different crystallinity, specific surface area, and surface structure. PS demonstrated the equilibrium sorption capacity, namely, 6.41 ng/g BDE-47, 12.83 ng/g BDE-99, and 14.42 ng/g BDE-153. The second-order kinetic model described the sorption kinetics of PBDEs, and surface sorption was the main mechanism. The sorption of PBDEs by microplastics was a multilayer and physical process. Low temperatures reduced BDE-47 sorption on microplastics, and sorption was a spontaneous and endothermic process. The sorption of BDE-47 was not significantly influenced by pH and salinity. However, DOM exerted a negative effect on the sorption of BDE-47.
•Sorption of PBDEs on the four microplastics followed the order of PS > PA > PP > PE.•Second-order kinetics and particle diffusion model described the sorption of PBDEs.•Sorption of PBDEs was a multilayer and spontaneous endothermic process.•Salinity and pH had no significant impact on PBDEs sorption.•The presence of DOM exerted a negative effect on the sorption of PBDEs.
Accurate estimation of global evapotranspiration (ET) is essential to understand water cycle and land-atmosphere feedbacks in the Earth system. Satellite-driven ET models provide global estimates, ...but many of the ET algorithms have been designed independently of soil moisture observations. As water for ET is sourced from the soil, incorporating soil moisture into global remote sensing algorithms of ET should, in theory, improve performance, especially in water-limited regions. This paper presents an update to the widely-used Priestley Taylor-Jet Propulsion Laboratory (PT-JPL) ET algorithm to incorporate spatially explicit daily surface soil moisture control on soil evaporation and canopy transpiration. The updated algorithm is evaluated using 14 AmeriFlux eddy covariance towers co-located with COsmic-ray Soil Moisture Observing System (COSMOS) soil moisture observations. The new PT-JPLSM model shows reduced errors and increased explanation of variance, with the greatest improvements in water-limited regions. Soil moisture incorporation into soil evaporation improves ET estimates by reducing bias and RMSE by 29.9% and 22.7% respectively, while soil moisture incorporation into transpiration improves ET estimates by reducing bias by 30.2%, RMSE by 16.9%. We apply the algorithm globally using soil moisture observations from the Soil Moisture Active Passive Mission (SMAP). These new global estimates of ET show reduced error at finer spatial resolutions and provide a rich dataset to evaluate land surface and climate models, vegetation response to changes in water availability and environmental conditions, and anthropogenic perturbations to the water cycle.
•A soil moisture constraint is introduced to the widely-used PT-JPL ET model.•The new ET algorithm is applied globally using SMAP soil moisture observations.•SMAP data improves ET most in dry areas with large fractions of soil evaporation.•Soil moisture integration into soil evaporation reduces errors in ET by 23%.•Soil moisture integration into transpiration reduces errors in ET by 17%.
Auxins are plant hormones that play a central role in controlling plant growth and development across different environmental conditions. Even at low concentrations, auxins can regulate gene ...expression through specific transcription factors and proteins that are modulated to environmental responses in the signalling cascade. Auxins are synthesized in tissues with high cell division activity and distributed by specific transmembrane proteins that regulate efflux and influx. This review presents recent advances in understanding the biosynthetic pathways, both dependent and independent of tryptophan, highlighting the intermediate indole compounds (indole‐3‐acetamide, indole‐3‐acetaldoxime, indole‐3‐pyruvic acid and tryptamine) and the key enzymes for auxin biosynthesis, such as YUCs and TAAs. In relation to the signalling cascade, it has been shown that auxins influence gene expression regulation by the connection between synthesis and distribution. Moreover, the molecular action of the auxin response factors and auxin/indole‐3‐acetic acid transcription factors with the F‐box TIR1/AFB auxin receptors regulates gene expression. In addition, the importance of microRNAs in the auxin signalling pathway and their influence on plant plasticity to environmental fluctuations is also demonstrated. Finally, this review describes the chemical and biological processes involving auxins in plants.
Auxin‐integrating chemical and molecular processes are involved in plant growth and development, regulated by the synthesis and distribution of the phytohormon.
The interest in using natural antimicrobials instead of chemical preservatives in food products has been increasing in recent years. In regard to this, essential oils-natural and liquid secondary ...plant metabolites-are gaining importance for their use in the protection of foods, since they are accepted as safe and healthy. Although research studies indicate that the antibacterial and antioxidant activities of essential oils (EOs) are more common compared to other biological activities, specific concerns have led scientists to investigate the areas that are still in need of research. To the best of our knowledge, there is no review paper in which antifungal and especially antimycotoxigenic effects are compiled. Further, the low stability of essential oils under environmental conditions such as temperature and light has forced scientists to develop and use recent approaches such as encapsulation, coating, use in edible films, etc. This review provides an overview of the current literature on essential oils mainly on antifungal and antimycotoxigenic but also their antibacterial and antioxidant activities. Additionally, the recent applications of EOs including encapsulation, edible coatings, and active packaging are outlined.
•We modeled the HDR of Chinese fir by using random forest.•We further examined the interactive effects of neighborhood variables and environmental conditions on the HDR of Chinese fir.•Our findings ...can provide guidance for managing Chinese fir forests to improve their stability.
In forest dynamics modeling and estimation, the nonlinear relationship between response and explanatory variables is often concerned, while the interaction among variables is neglected. Height-to-diameter ratio (HDR) is an important indicator for evaluating tree stability and performance. Based on the data from 112 forest inventory plots across Hunan province, China, we modeled the HDR of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook) by using random forest and examined the interactive effects of neighborhood variables (neighborhood competition, density and mean diameter) and environmental conditions (dominant height, topography and climate) on the HDR of Chinese fir. Neighborhood competition contributed the most to HDR variation and affected HDR positively. Dominant height and elevation also had a strong influence on HDR. Furthermore, the changes in HDR were jointly dominated by neighborhood features and environmental conditions. For example, HDR varied from 50.5 to 80.3 under the interactive influence of neighborhood competition and dominant height, but varied from 56.8 to 70.2 under the influence of neighborhood competition alone. The relationship between HDR and neighborhood variables might be mediated by environmental conditions, while neighborhood variables did not change the overall trend of HDR responses to environmental factors. When the dense Chinese fir stand is located at low elevation (<500 m) or rich sites (>20 m), frequent and systematic thinning should be carried out in the early stages of forest development. Our findings can provide guidance for managing Chinese fir forests to improve their stability.
During the twentieth century, the Soviet Union turned the Kola Peninsula in the northwest corner of the country into one of the most populated, industrialized, militarized, and polluted parts of the ...Arctic. This transformation suggests, above all, that environmental relations fundamentally shaped the Soviet experience. Interactions with the natural world both enabled industrial livelihoods and curtailed socialist promises. Nature itself was a participant in the communist project. Taking a long-term comparative perspective, The Nature of Soviet Power sees Soviet environmental history as part of the global pursuit for unending economic growth among modern states. This in-depth exploration of railroad construction, the mining and processing of phosphorus-rich apatite, reindeer herding, nickel and copper smelting, and energy production in the region examines Soviet cultural perceptions of nature, plans for development, lived experiences, and modifications to the physical world. While Soviet power remade nature, nature also remade Soviet power.
The plasma membrane (PM) is possibly the most diverse biological membrane of plant cells; it separates and guards the cell against its external environment. It has an extremely complex structure ...comprising a mosaic of lipids and proteins. The PM lipids are responsible for maintaining fluidity, permeability and integrity of the membrane and also influence the functioning of membrane proteins. However, the PM is the primary target of environmental stress, which affects its composition, conformation and properties, thereby disturbing the cellular homeostasis. Maintenance of integrity and fluidity of the PM is a prerequisite for ensuring the survival of plants during adverse environmental conditions. The ability of plants to remodel membrane lipid and protein composition plays a crucial role in adaptation towards varying abiotic environmental cues, including high or low temperature, drought, salinity and heavy metals stress. The dynamic changes in lipid composition affect the functioning of membrane transporters and ultimately regulate the physical properties of the membrane. Plant membrane‐transport systems play a significant role in stress adaptation by cooperating with the membrane lipidome to maintain the membrane integrity under stressful conditions. The present review provides a holistic view of stress responses and adaptations in plants, especially the changes in the lipidome and proteome of PM under individual or combined abiotic stresses, which cause alterations in the activity of membrane transporters and modifies the fluidity of the PM. The tools to study the varying lipidome and proteome of the PM are also discussed.
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