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Maintaining plant productivity and crop yield in a warming world requires local adaptation to new environment and selection of high-yield cultivars, which both depend on the genetically-based intraspecific differences in the plant response to warming (referred to as "genetically-based intraspecific responses"). However, how the genetically-based intraspecific responses mediate warming effects on plants remains unclear, especially at the global scale. Here, a dataset was compiled from 118 common-garden experiments to examine the responses of plant growth, productivity, and crop yield to warming among different ecotypes/genotypes/cultivars. Our results showed that the genetically-based intraspecific responses on average accounted for 34.7 % of the total variance in the warming responses across all the studies but with large variability (2 %-77 %). The intraspecific responses of plant productivity and crop yield were larger than those of organ level traits and biomass allocation, suggesting that plant growth was mainly achieved by iterating the relatively invariant terminal modules (e.g., leaves). The warming-induced changes in intraspecific variability of aboveground biomass were larger in woody plants, non-leguminous herbs, perennial herbs and noncrops than those in nonwoody, leguminous, annual and crop ones, respectively, indicating the potential important role of plant longevity in mediating the change in intraspecific variability. Moreover, larger intraspecific responses reduced the consistence of relative performance between control and warming treatments for both plant productivity and crop yield. These results highlight the unneglectable role of genetically-based intraspecific differences in plant responses to warming, indicating the difficulty of maintaining high crop yield and tree productivity under global climate change, and posing a grave threat to the food security and wood supply in the near future., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Global temperatures are increasing, affecting timing and availability of vegetation along with relationships between plants and their consumers. We examined the effect of population density, herd body condition in the previous year, elevation, plant productivity and phenology, snow, and winter onset on juvenile body mass in 63 semi-domesticated populations of Rangifer tarandus throughout Norway using spatiotemporal generalized additive models (GAMs) and varying coefficient models (VCMs). Optimal climate windows were calculated at both the regional and national level using a novel nonlinear climate window algorithm optimized for prediction. Spatial and temporal variation in effects of population and environmental predictors were considered using a model including covariates decomposed into spatial, temporal, and residual components. The performance of this decomposed model was compared to spatiotemporal GAMs and VCMs. The decomposed model provided the best fit and lowest prediction errors. A positive effect of herd body condition in the previous year explained most of the deviance in calf body mass, followed by a more complex effect of population density. A negative effect of timing of spring and positive effect of winter onset on juvenile body mass suggested that a snow free season was positive for juvenile body mass growth. Our findings suggest early spring onset and later winter permanent snow cover as reinforcers of early-life conditions which support more robust reindeer populations. Our methodological improvements for climate window analyses and effect size measures for decomposed variables provide important contributions to account for, measure, and interpret nonlinear relationships between climate and animal populations at large scales., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Spring green-up date (GUD) is a sensitive indicator of climate change, and of great significance to winter wheat production. However, our knowledge of the chain relationships among them is relatively weak. In this study, based on 8-day Enhanced Vegetation Index (EVI) data from Moderate Resolution Imaging Spectroradiometer (MODIS) from 2001 to 2015, we first assessed the performance of four algorithms for extracting winter wheat GUD in the North China Plain (NCP). A multiple linear regression model was then established to quantitatively determine the contributions of the time lag effects of hydrothermal variation on GUD. We further investigated the interactions between GUD and gross primary production (GPP) comprehensively. Our results showed that the rate of change in curvature algorithm (RCCmax) had better performance in capturing the spatiotemporal variation of winter wheat GUD relative to the other three methods (Kmax, CRmax, and cumCRmax). Regarding the non-identical lag time effects of hydrothermal factors, hydrothermal variations could explain winter wheat GUD variations for 82.05% of all pixels, 36.78% higher than that without considering the time lag effects. Variation in GUD negatively correlated with winter wheat GPP after green up in most parts of the NCP, significantly in 35.75% of all pixels with a mean rate of 1.89 g C m -2  yr -1  day -1 . Meanwhile, winter wheat GPP exerted a strongly positive feedback on GUD in >82.42% of all pixels (significant in 28.01% of all pixels), characterized by a humped-shape pattern along the long-term average plant productivity. This finding highlights the complex interaction between spring phenology and plant productivity, and also suggests the importance of preseason climate factors on spring phenology., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Coastal wetlands are among the most productive and carbon-rich ecosystems on Earth. Long-term carbon storage in coastal wetlands occurs primarily belowground as soil organic matter (SOM). In addition to serving as a carbon sink, SOM influences wetland ecosystem structure, function, and stability. To anticipate and mitigate the effects of climate change, there is a need to advance understanding of environmental controls on wetland SOM. Here, we investigated the influence of four soil formation factors: climate, biota, parent materials, and topography. Along the northern Gulf of Mexico, we collected wetland plant and soil data across elevation and zonation gradients within 10 estuaries that span broad temperature and precipitation gradients. Our results highlight the importance of climate-plant controls and indicate that the influence of elevation is scale and location dependent. Coastal wetland plants are sensitive to climate change; small changes in temperature or precipitation can transform coastal wetland plant communities. Across the region, SOM was greatest in mangrove forests and in salt marshes dominated by graminoid plants. SOM was lower in salt flats that lacked vascular plants and in salt marshes dominated by succulent plants. We quantified strong relationships between precipitation, salinity, plant productivity, and SOM. Low precipitation leads to high salinity, which limits plant productivity and appears to constrain SOM accumulation. Our analyses use data from the Gulf of Mexico, but our results can be related to coastal wetlands across the globe and provide a foundation for predicting the ecological effects of future reductions in precipitation and freshwater availability. Coastal wetlands provide many ecosystem services that are SOM dependent and highly vulnerable to climate change. Collectively, our results indicate that future changes in SOM and plant productivity, regulated by cascading effects of precipitation on freshwater availability and salinity, could impact wetland stability and affect the supply of some wetland ecosystem services., (Published 2018. This article is a U.S. Government work and is in the public domain in the USA.)

It is unclear how elevated CO2 (eCO2 ) and the corresponding shifts in temperature and precipitation will interact to impact ecosystems over time. During a 7-year experiment in a semi-arid grassland, the response of plant biomass to eCO2 and warming was largely regulated by interannual precipitation, while the response of plant community composition was more sensitive to experiment duration. The combined effects of eCO2 and warming on aboveground plant biomass were less positive in 'wet' growing seasons, but total plant biomass was consistently stimulated by ~ 25% due to unique, supra-additive responses of roots. Independent of precipitation, the combined effects of eCO2 and warming on C3 graminoids became increasingly positive and supra-additive over time, reversing an initial shift toward C4 grasses. Soil resources also responded dynamically and non-additively to eCO2 and warming, shaping the plant responses. Our results suggest grasslands are poised for drastic changes in function and highlight the need for long-term, factorial experiments., (© 2016 John Wiley & Sons Ltd/CNRS.)

Perennially frozen soil in high latitude ecosystems (permafrost) currently stores 1330-1580 Pg of carbon (C). As these ecosystems warm, the thaw and decomposition of permafrost is expected to release large amounts of C to the atmosphere. Fortunately, losses from the permafrost C pool will be partially offset by increased plant productivity. The degree to which plants are able to sequester C, however, will be determined by changing nitrogen (N) availability in these thawing soil profiles. N availability currently limits plant productivity in tundra ecosystems but plant access to N is expected improve as decomposition increases in speed and extends to deeper soil horizons. To evaluate the relationship between permafrost thaw and N availability, we monitored N cycling during 5 years of experimentally induced permafrost thaw at the Carbon in Permafrost Experimental Heating Research (CiPEHR) project. Inorganic N availability increased significantly in response to deeper thaw and greater soil moisture induced by Soil warming. This treatment also prompted a 23% increase in aboveground biomass and a 49% increase in foliar N pools. The sedge Eriophorum vaginatum responded most strongly to warming: this species explained 91% of the change in aboveground biomass during the 5 year period. Air warming had little impact when applied alone, but when applied in combination with Soil warming, growing season soil inorganic N availability was significantly reduced. These results demonstrate that there is a strong positive relationship between the depth of permafrost thaw and N availability in tundra ecosystems but that this relationship can be diminished by interactions between increased thaw, warmer air temperatures, and higher levels of soil moisture. Within 5 years of permafrost thaw, plants actively incorporate newly available N into biomass but C storage in live vascular plant biomass is unlikely to be greater than losses from deep soil C pools., (© 2015 John Wiley & Sons Ltd.)

Aims: Changes in precipitation patterns, such as the predicted increases in the frequency of climatic extremes, are likely to alter plant communities, but whether responses to drought or to wetter conditions respectively cause consistent, opposite responses is debated. Here, we assessed the response in biomass production and species diversity of water‐limited plant communities to the direction (increase or decrease) and magnitude (micro‐ and macro‐climatic effects) of changes in soil moisture. Location: We reciprocally translocated soils containing seed banks from two climates (semi‐arid and mediterranean) at a micro‐climatic (opposite slopes) and a macro‐climatic scale (between climates) in Chile. Results: Biomass production for the soils that were translocated from wetter to drier climates was unrelated to the available soil moisture. The lowest biomass was produced in the wettest climate on the wet slope. Biomass production increased after a translocation to the drier climate (representing the largest change in climate). Nonetheless, the highest overall biomass for the wet to dry translocation was produced on the mediterranean dry slope with intermediate soil moisture. However, on the same mediterranean dry slope, biomass was almost zero for soil translocated the other way round (from drier to wetter). Diversity after 24 months was unaffected by micro‐climatic change, but soils transplanted toward the drier climate yielded a plant community with increased diversity. Conclusion: Our results showed direction and magnitude of climate change but also the response factor that is studied matters to detect direction‐dependent responses; i.e., species richness had a linear and reversible response. However, the response of biomass depended on the origin of the transplanted material (soil and plant community), indicating history dependence (hysteresis). This emphasizes that responses to unidirectional climate manipulation experiments may not be able to capture the entire nature of the response of plant communities to climate change. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Cultural use berries are prized foods and medicines across the United States and Canada, with almost 200 different species used by Indigenous Peoples. Berries are increasingly being impacted by environmental and land‐use change. Berry habitats, how and when berry plants reproduce, and the volume of berries available for harvest each year are shifting widely. These changes are impacting access to, availability of, and consumption of berries. Biocultural stewardship practices, like low‐intensity fire, transplanting, and thinning, can be used in response to these stressors to support berry plant health and productivity as well as a sustained relationship with this important food. Summary: Almost 200 different species of berries are used for food and medicine by Indigenous Peoples, with unparalleled nutritional and cultural significance among plant foods. Environmental and land‐use change is increasingly compromising access to, availability of, and consumption of berries. In this review, I consider (a) how climate and land‐use change are impacting cultural use berries across species and places, as documented by Indigenous Peoples and in the scientific literature, and (b) how stewardship practices are being applied to promote resilience and sustainability in berrying landscapes experiencing stress. Climate impacts on Arctic and subarctic berry species include earlier ripening, changes in taste, or increased variability in abundance. These same regions are experiencing a proliferation of shrubs, while forests throughout the lower 48 and Canada are suffering from suffocating fuel loads and stand densities that are not conducive to berry habitat for many species. In the Pacific West, berries are influenced by prolonged droughts and increasing spring and summer temperatures. Climate change impacts are amplified by shifts in land use for forestry and agriculture. Biocultural stewardship practices, like low‐intensity fire, thinning, transplanting, and cultural care, can be used to mitigate these impacts and promote berry microclimate habitats. There is opportunity for intertribal networking and knowledge sharing around berry stewardship practices that will support local and regional climate change responses. [ABSTRACT FROM AUTHOR]

The land sink of anthropogenic carbon emissions, a crucial component of mitigating climate change, is primarily attributed to the CO2 fertilization effect on global gross primary productivity (GPP). However, direct observational evidence of this effect remains scarce, hampered by challenges in disentangling the CO2 fertilization effect from other long‐term confounding drivers, particularly climatic changes. Here, we introduce a novel statistical approach to separate the CO2 fertilization effect on photosynthetic carbon uptake using eddy covariance (EC) records across 38 extratropical forest sites. We find the median stimulation rate of GPP to be 3.2 ± 0.9 gC m−2 yr−1 ppm−1 (or 16.4 ± 4.2% per 100 ppm) under increasing atmospheric CO2 across these sites, respectively. To validate the robustness of our findings, we test our statistical method using factorial simulations of an ensemble of process‐based land surface models. We address additional factors, including nitrogen deposition and land management, that may impact plant productivity, potentially confounding the attribution to the CO2 fertilization effect. Assuming these site‐specific effects offset to some extent across sites as random factors, the estimated median value still reflects the strength of the CO2 fertilization effect. However, disentanglement of these long‐term effects, often inseparable by timescale, requires further causal research. Our study provides direct evidence that the photosynthetic stimulation is maintained under long‐term CO2 fertilization across multiple EC sites. Such observation‐based quantification is key to constraining the long‐standing uncertainties in the land carbon cycle under rising CO2 concentrations. Plain Language Summary: Through photosynthesis, plants convert CO2 and water into sugars and oxygen using solar energy, one of the most important chemical reactions on Earth. Human‐made carbon emissions are increasing atmospheric CO2 levels, impacting global photosynthesis. The additional carbon is believed to have a fertilizing effect on photosynthesis, causing vegetation to absorb a significant portion of the emitted CO2. However, the strength of this CO2 fertilization effect on photosynthesis is uncertain, but is a crucial factor in determining the future trajectory of atmospheric CO2 concentrations. In this study, we introduce a new statistical method to quantify the increase in photosynthetic carbon uptake, stimulated by rising CO2, based on measurements from 38 forest sites. Our results reveal that a 100 ppm increase in CO2 enhances photosynthesis by approximately 16%. Testing the statistical method with artificial model experiments supports the robustness of our findings. Our study improves the understanding of the impacts of human‐made CO2 emissions on the global carbon cycle. Key Points: We present a novel statistical method to disentangle the variability of photosynthetic rates related to climate and non‐climate driversThe analysis from 38 eddy covariance sites reveals a 3.2 ± 0.9 gC m−2 yr−1 increase in plant productivity per ppm rise in CO2Our statistical method is successfully tested against idealized model simulations with and without increasing CO2 [ABSTRACT FROM AUTHOR]

Highly productive soils in Ukraine have been losing their main quality indicators in the last decade. This is due to the violation of basic agricultural laws, particularly in the selection of agricultural crops in crop rotation, climate change, and other negative manifestations. Successful farming in the South Steppe zone of Ukraine significantly depends on moisture conditions, specifically the amount of precipitation during plant vegetation and initial moisture reserves during sowing. The first limiting factor for crop yields in arid regions is moisture. Depleted and compacted soils are unable to accumulate and retain it. Under such conditions, it is necessary to develop new approaches and implement the previously developed technological measures that would contribute to increasing the productivity of agricultural crops while preserving soil fertility. This involves enriching soils with organic matter, which structures them as well as increases their water absorption and retention capacity. In the absence of manure in the fields, it is advisable to use post-harvest residues of all crops and straw. These are the most resource-efficient and environmentally friendly measures. It has been determined that incorporating straw into the soil can increase the yield and quality of agricultural crops, as demonstrated in the cultivation of sorghum. [ABSTRACT FROM AUTHOR]

Tibetan Plateau (TP) has experienced a slowdown of the vegetation greening since the late 1990s. This structural change (i.e., greening) along with canopy physiology (i.e., potential photosynthetic productivity) regulates vegetation gross primary productivity (GPP). However, it remains unclear how the joint regulation influences the trend of alpine GPP under climate change. Here, we validate a universal productivity model against flux‐based and satellite‐derived observations at TP and diagnose the long‐term climatic impacts on GPP via canopy physiology and structure. We found an increasing but weakening trend of GPP after 1998. About 3/4 of this slowdown was attributed to the slowing greening after 1998, which was caused by the fact that the stress of atmospheric aridity and reduced benefits of warming overwhelmed the positive effects of CO2 fertilization and radiation enhancement. This study highlights the coupling between canopy structure and productivity for the long‐term period. Plain Language Summary: Plants absorb CO2 from the atmosphere through their leaves via process of photosynthesis. The green surface area of leaves and portions exposed to sunlight harvest the energy from the sun, while the plant's physiology determines how much and how well light radiation is used. The Tibetan Plateau is one of the most sensitive regions to climate change and has experienced a slowdown since 1998 of its hitherto increasing total vegetation greenness. An important point that remains unclear is whether, and to what proportion this slowdown in the capacity to absorb CO2 is attributed to the green canopy vegetation and/or its physiology. To gain insight into this question, we input data from 1982 to 2015 into a simulation model to separate the contributions of different environmental factors that brought about variation in CO2 capture. In this way we can understand what factors related to the canopy structure and/or plant physiology. We found that increased atmospheric aridity and reduced warming together led to a marked slowdown of canopy greening after 1998, leading to a continuous decline in efficiency to capture atmospheric CO2. Our research continues to highlight the important role of canopy structure on carbon capture trends for the alpine ecosystem and provides insights for the vegetation‐climate response. Key Points: The increasing trend of gross primary productivity on the Tibetan Plateau has slowed down from +3.15 ± 0.41 to +0.77 ± 0.03 g C m−2 yr−2 around 1990sCanopy greenness change contributed much more (about 3/4) to slow the gross primary productivity (GPP) increasing trend than canopy physiology effects after 1998Increasing atmospheric aridity and slowing warming rate diminished the persistent greening and led to the slowdown of increasing GPP [ABSTRACT FROM AUTHOR]

One of the ways in which plants are responding to climate change is by shifting their ranges to higher elevations. Early life‐history stages are major bottlenecks for species' range shifts, and variation in seedling emergence and establishment success can therefore be important determinants of species' ability to establish at higher elevations. Previous studies have found that warming per se tends to not only increase seedling establishment in alpine climates but it also increases plant productivity, which could limit establishment success through increased competition for light. Here we disentangle the relative importance of several climate‐related abiotic and biotic factors on sub‐alpine species' seedling emergence and survival in the alpine. Specifically, we test how temperature, precipitation and competition from neighbouring vegetation impacts establishment, and also whether species' functional traits, or strategies impact their ability to colonise alpine locations. We found that our six sub‐alpine study species were all able to recruit from seed in alpine locations under the extant alpine climate, but their emergence was limited by competition from neighbouring vegetation. This indicates that biotic interactions can hinder the range shifts expected as a result of climate warming. Species with a resource conservative strategy had higher emergence in the extant alpine climate than species with a resource acquisitive strategy, and they were largely unaffected by changes in temperature. The resource acquisitive species, in contrast, had faster emergence under warming, especially when they were released from competition from neighbouring vegetation. Our results indicate that competition from the established vegetation is limiting the spread of lowland species into the alpine, and as the climate continues to warm, species with resource acquisitive traits might gain an advantage. [ABSTRACT FROM AUTHOR]

Photosynthesis is responsible for sustained plant productivity and ensures food supply. The change in global climatic patterns affects photosynthesis that subsequently reduces plant yield and poses threat to food security. Photosynthesis relies on a dual nature enzyme ribulose 1, 5 bisphosphate carboxylase oxygenase (Rubisco), which can fix CO2 as well as O2. The fixation rate of CO2 to O2 depends upon the relative concentration of CO2 inside chloroplast. Higher level of CO2 results in improved photosynthesis, however, its concentration depends upon environmental conditions. Under adverse climate conditions, the CO2 level drops down that leads to increased oxygenation which impedes the photosynthesis and reduces plant productivity. The impact is more significant and apparent specifically in C3 plants. Attempts have been made to address the loss in photosynthesis and multiple strategies have been adapted to date that focus on improvement of photosynthesis in C3 plants. In this review, we have discussed the multiple strategies being employed by different researchers to date for improvement of photosynthesis. The strategies discussed in this review include: improving the performance of Rubisco, engineering CO2-concentrating mechanism of C4 photosynthesis into C3 species, transformation of bicarbonate transporters from cyanobacteria into chloroplasts of C3 plants, and establishment of photorespiratory bypasses to catabolise toxic glycolate in shortest possible pathway. [ABSTRACT FROM AUTHOR]

Climate models predict more frequent, prolonged, and extreme droughts in the future. Therefore, drought experiments varying in amount and duration across a range of biogeographical scenarios provide a powerful tool for estimating how drought will affect future ecosystems. Past experimental work has been focused on the manipulation of meteorological drought: Rainout shelters are used to reduce precipitation inputs into the soil. This work has been instrumental in our ability to predict the expected effects of altered rainfall. But what about the nonrainfall components of drought? We review recent literature on the co-occurring and sometimes divergent impacts of atmospheric drying and meteorological drying. We discuss how manipulating meteorological drought or rainfall alone may not predict future changes in plant productivity, composition, or species interactions that result from climate change induced droughts. We make recommendations for how to improve these experiments using manipulations of relative humidity. [ABSTRACT FROM AUTHOR]

Extreme high temperature has become more common as a result of global warming which acts as a key abiotic stress that inhibits plant development and productivity. In this research, drought-exposed Ananas comosus clonal plantlets were triggered to specific physiological responses to overcome the effect of drought stress. The plantlets of A. comosus were placed in a greenhouse with recorded temperatures ranging between 32°C to 36°C and treated with three different watering conditions which are once a week (Treatment 1/control), once every two weeks (Treatment 2), and not watered at all (Treatment 3). The first obvious morphological effect is wilting, drying out of the tips or edge of leaves, and yellowing or browning of leaves. Treatment 1 (control) recorded the lowest plant wilting number and the highest in the mean of leaves length among other samples. In Treatment 2, a higher amount of plant wilting with a lower amount in the mean of leaves length as compared to Treatment 1 was observed. Meanwhile, Treatment 3 recorded the highest wilting record as well as the lowest mean of leaves length. The physiological changes in stomata conductance have greater conductance for Treatment 1 with more open stomata and obvious pores followed by Treatment 2 with stomata opened slightly and Treatment 3 was observed to have sunken stomata and the pores were hardly seen. The physiological changes of stomata have shown the mechanism of adaptation in clonal plantlets to control transpiration and prevent dehydration under thermal and drought stress. [ABSTRACT FROM AUTHOR]

Climate change is contributing to declines of insects through rising temperatures, altered precipitation patterns, and an increasing frequency of extreme events. The impacts of both gradual and sudden shifts in weather patterns are realized directly on insect physiology and indirectly through impacts on other trophic levels. Here, we investigated direct effects of seasonal weather on butterfly occurrences and indirect effects mediated by plant productivity using a temporally intensive butterfly monitoring dataset, in combination with high‐resolution climate data and a remotely sensed indicator of plant primary productivity. Specifically, we used Bayesian hierarchical path analysis to quantify relationships between weather and weather‐driven plant productivity on the occurrence of 94 butterfly species from three localities distributed across an elevational gradient. We found that snow pack exerted a strong direct positive effect on butterfly occurrence and that low snow pack was the primary driver of reductions during drought. Additionally, we found that plant primary productivity had a consistently negative effect on butterfly occurrence. These results highlight mechanisms of weather‐driven declines in insect populations and the nuances of climate change effects involving snow melt, which have implications for ecological theories linking topographic complexity to ecological resilience in montane systems. [ABSTRACT FROM AUTHOR]

In this era of global climate change, land degradation and biodiversity loss have had significant impact on photosynthesis and productivity of the plant kingdom. The forestry and agricultural sectors also emit greenhouse gases such as CH4, N2O etc. which contribute to global warming. On the other hand, forestry and agricultural sectors are most vulnerable and sensitive to climate change, since the growth and productivity of these sectors depend on local climate parameters such as temperature, humidity, rainfall, solar radiation, soil health etc. The impact of climate change events varies regionally. This paper provides an overview of the potential impact of climate change on crop productivity. It also explains in detail the threats and possible opportunities in dealing with the changing climate. [ABSTRACT FROM AUTHOR]

Interannual variability of vegetation activity (i.e., photosynthesis) is strongly correlated with El Niño Southern Oscillation (ENSO). Globally, a reduction in carbon uptake by terrestrial ecosystems has been observed during the ENSO warm phase (El Niño) and the opposite during the cold phase (La Niña). However, this global perspective obscures the heterogeneous impacts of ENSO at regional scales. Particularly, ENSO has contrasting impacts on climate in northern South America (NSA) depending on the ENSO phase and geographical location, which in turn affect the activity of vegetation. Furthermore, changes of vegetation activity during multiple ENSO events are not well understood yet. In this study, we investigated the spatial and temporal differences in vegetation activity associated with ENSO variability and its three phases (El Niño, La Niña, Neutral) to identify hotspots of ENSO impacts in NSA, a region dominated by rainforest and savannas. To achieve this, we investigated time series of vegetation variables from 2001 to 2014 at moderate spatial resolution (0.0083°). Data were aggregated through dimensionality reduction analysis (i.e., Global Principal Component Analysis). The leading principal component served as a proxy of vegetation activity (VAC). We calculated the cross‐correlation between VAC and the multivariate ENSO index separately for each ENSO phase. Our results show that El Niño phase has a stronger impact on vegetation activity both in intensity and duration than La Niña phase. Moreover, seasonally dry ecoregions were more susceptible to El Niño impacts on vegetation activity. Understanding these differences is key for regional adaptation and differentiated management of ecosystems. Plain Language Summary: Precipitation and temperature are important climatic drivers of vegetation processes. In particular, El Niño Southern Oscillation (ENSO) events are related to changes in precipitation and temperature over large regions, which in turn affects the activity of the vegetation. In northern South America (NSA), these changes on climate are opposite during the same ENSO event depending on the geographical location. Moreover, local conditions and vegetation type can moderate or amplified changes in vegetation activity. Currently, the contrasting vegetation changes during the ENSO warm (El Niño) and cold (La Niña) phase are not well understood in NSA. Furthermore, it is unknown where the largest vegetation variability is occurring during ENSO phases. We combined different vegetation variables related to vegetation greenness and plant productivity over 14 years to estimate changes in vegetation activity related to photosynthesis. In this way, we assessed the variability of vegetation activity during El Niño and La Niña. We found that variability of vegetation activity is stronger and longer during El Niño than La Niña. In addition, vegetation in semi‐arid ecoregions was more susceptible to El Niño. A better understating of how vegetation activity varies during different ENSO phases will improve regional conservation strategies under the increasing ENSO frequencies. Key Points: Interannual variability of vegetation activity in northern South America is related to changes in climate due to El Niño and La Niña eventsEl Niño events have a stronger impact on vegetation activity both in intensity and duration than La Niña eventsSemi‐arid ecoregions are the most vulnerable to El Niño, but further investigation is required to understand underlying processes [ABSTRACT FROM AUTHOR]

Climate change has become one of the most significant risk factors in agricultural production. Plant productivity declines caused by climate change pose a serious threat to food supply and security. Crop simulation models have been widely used in recent years for the assessment of the impacts of climate change on agricultural production. In Konya, there have been limited studies on the potential effects of climate change on sunflower production. Sunflower, the main crop of the most imported agricultural product group, in which the production amount is currently insufficient to cover domestic consumption demand, is strategically important for the Turkish economy. The goal of this study was to examine the effects of climate change on sunflower yield in Türkiye by using the Aquacrop model. The data of the field experiment carried out on the Ekllor sunflower cultivar for two years in Konya conditions were used as material. The daily projection dataset of three Global Climate Models (HadGEM2- ES, MPI-ESM-MR, GFDL-ESM2M) and two scenarios (RCP4.5 and RCP8.5) were used to analyze climate change impacts. The 1971-2000 period was considered as the reference period and the 2022-2098 period was selected as the future period. The results confirmed that the Aquacrop model was able to satisfactorily simulate yield with NRMSE 2.10 % for the rainfed condition and 10.55 % for the irrigated condition, a d-index of 0.97, and a modeling efficiency of 0.91. Aqaucrop climate change impacts simulation which was based on 3 global climate models covering with 2022 -2098 period simulations projected that sunflower yield would be decreased in a range of 21% to 44% for RCP4.5 and 18% to 50% for RCP8.5 scenarios under rainfed conditions. In contrast, the yield would be increased in a range of 11% to 23% for RCP4.5 and 10% to 33% for RCP8.5 scenarios under irrigated conditions. The findings point to the use of appropriate water management measures for future sunflower production as a means of adapting to climate change. [ABSTRACT FROM AUTHOR]

Climatic and soil conditions are changing in response to the increasing human impact. This requires the introduction of low-cost, low-emission, but effective technologies in the field cultivation of crops, in turn requiring and justifying research in this area. In laboratory tests and field studies, the production and environmental effects of strip-till and the application of microgranular fertilisers with a gelling component were determined (and, in particular, their use in combination as a plant cultivation technology). These effects were measured in terms of soil properties, the biomass production, and the yields of maize (Zea mays L.), spring barley (Hordeum vulgare L.), and winter rape (Brassica napus L.). Fertiliser microgranules with a gelling agent absorbed water in the amount of 118.6–124.7% of fertiliser mass and increased the volumetric moisture content of the soil in the layer in which they were applied (0–7.5 cm) by 3.0–3.9 percentage points compared to the soil moisture without fertiliser. Strip tillage with the application of fertilisers with a gelling agent significantly increased the amount of water in the soil during the sowing period for winter and spring plants and reduced the CO2 emissions from the soil relative to the conventional tillage without microgranular fertiliser. The biomass of maize, spring barley, and winter rape before flowering, as well as the yields of these plants, were higher when cultivated using strip-till and fertilisers with gelling agents than when ploughed with a mouldboard plough without the use of microgranulated fertilisers. This technology also increased the number of microorganisms, including bacteria, actinobacteria, and filamentous fungi in the soil after harvesting compared to the unfertilised, ploughed soil. Strip tillage and microgranulated fertilisers containing a gelling agent can thus reduce the environmental pressure exerted by agriculture and reduce the risk of climate change, as well as being a way of adapting agriculture to climate change. [ABSTRACT FROM AUTHOR]

Abstract Tibetan Plateau (TP) has experienced a slowdown of the vegetation greening since the late 1990s. This structural change (i.e., greening) along with canopy physiology (i.e., potential photosynthetic productivity) regulates vegetation gross primary productivity (GPP). However, it remains unclear how the joint regulation influences the trend of alpine GPP under climate change. Here, we validate a universal productivity model against flux‐based and satellite‐derived observations at TP and diagnose the long‐term climatic impacts on GPP via canopy physiology and structure. We found an increasing but weakening trend of GPP after 1998. About 3/4 of this slowdown was attributed to the slowing greening after 1998, which was caused by the fact that the stress of atmospheric aridity and reduced benefits of warming overwhelmed the positive effects of CO2 fertilization and radiation enhancement. This study highlights the coupling between canopy structure and productivity for the long‐term period.

The art of utilizing and manipulating micro materials have been dated back to antient era. With the advancement in technologies, the state-of-art methods of nano technologies and nano sciences has been employed in various sectors including environment, product designing, food industry, pharmaceuticals industries to way out solve standard problem of mankind. Due to rapid industrialization and the alarming levels of pollution there has been an urgent need to address the environmental and energy issues. Environmental sustainability concerns the global climate change and pollution including air, water, soil. The field of nanotechnology has proven to be a promising field where sensing and remediation, have been dramatically advanced by the use of nanomaterials. This emergent science of surface to mass ratio is the principle theorem for manipulating structure at molecular levels. The review sums up all the advancements in the field of nanotechnology and their recent application in the environment. New opportunities and challenges have also been discussed in detail to understand the use of nanotechnology as problem-to-solution ratio. Image depicting the application of nanotechnology in environmental concerns. The combinations of technologies like bioremediations, bioaugmentations with state-of-the-art nanotechnology like carbon nanotubes and Nano capsules to answer the environmental challenges of soil quality, and plant productivity. [ABSTRACT FROM AUTHOR]

Owing to global climate changes, periods of soil drought or waterlogging occur. Each of these factors causes negative effects on plant physiological processes and growth. Weeds are another factor that limits plant productivity. The main task of this study is to investigate the physiological reactions of triticale to herbicide treatment and subsequent drought or waterlogging. Young triticale plants were treated with Serrate® (selective herbicide produced by Syngenta) and exposed for 7 days to drought or waterlogging. Plant growth, chlorophyll and carotenoids content, the net photosynthesis rate and chlorophyll a fluorescence were measured during the stress period and after 4 days of plant recovery. Herbicide by itself did not induce considerable changes in the abovementioned parameters during the stress period. Serrate® did not affect strongly the efficiency of the photosynthetic machinery under harsh conditions. A significant reduction in fresh weight (85%), water content (93%), net photosynthesis rate, chlorophyll a fluorescence indices Fv/Fm and Fv/F0, and leaf pigments (58% for chlorophyll a, 53% for chlorophyll b, and 45% for carotenoids) was found because of drought. Waterlogging also influenced negatively these parameters but to a smaller extent. After resuming the normal irrigation, the photosynthesis and chlorophyll a fluorescence tended to increase and showed signs of recovery. The comparative analysis of growth and photosynthetic parameters demonstrated that triticale plants subjected to waterlogging could recover to a higher degree than those exposed to drought. [ABSTRACT FROM AUTHOR]

Summary: Atmospheric vapor‐pressure deficit (VPD) is increasing in many regions and has a large impact on plant productivity. A VPD increase leads to raising transpiration rate (TR) and soil‐water demand, risking productivity penalties. Like water, nitrogen is critical to productivity, but the effect of VPD on legume nitrogen fixation is undocumented.To address this, we developed a portable system for quantifying nitrogen fixation noninvasively and at a high temporal resolution by tracking the rate of hydrogen gas evolution by root nodules. Combining field and controlled‐environment experiments where we measured leaf gas exchange and H2 production by nodules, we confirmed the ability of the system to track nitrogen fixation dynamics.Raising VPD from 0.5 to 3 kPa within c. 2.5 h under well‐watered conditions increased nitrogen fixation by up to 25% in addition to TR, consistent with the hypothesis that raising VPD in that range might have alleviated nitrogenase feedback inhibition. Genotypic differences were found in this response, indicating a potential for breeding.Our study provides evidence for an important environmental effect on nitrogen fixation that is not taken into account in current crop and vegetation models, pointing to untapped avenues for better understanding climate change effects on legumes and nitrogen cycling. [ABSTRACT FROM AUTHOR]

It has been established that the use of effective technologies for growing cereal crops in different soil-climatic conditions of Ukraine is of great importance in the modern conditions of climate change and other stress factors. Such technologies ensure the systematic and comprehensive use of science-based measures affecting the solution of global social problems of humanity, which were caused by climate change and the rf's full-scale war in Ukraine. For this purpose, the wide application of economic-mathematical methods is provided, which ensure the accuracy of obtaining the results of field research, the identification of previously unknown regularities for the favorable growth and development of cereal crops, especially in modern conditions of climate change and other stressful factors. With the use of dispersion analysis, the dynamics of the mutual influence of the main technological factors: varieties and hybrids of cereal crops, crop rotations, tillage, fertilization, plant protection and weather conditions on the productivity of cereal crops in the conditions of climatic changes in Ukraine during the second half of the 19th -- the beginning of the 21st centuries were evaluated. The share of mutual influence of the main technological factors and weather conditions on the productivity of the leading cereal, legumes and technical crops in Ukraine is calculated. It was found that the analysis of mathematically verified results of field studies contributes to increasing the reliability of conclusions, better assessment of the essence and solving of scientific-practical problems, establishing new urgent tasks for solving in the future. [ABSTRACT FROM AUTHOR]

Abiotic stress conditions, such as salinity, affect plant development and productivity and threaten the sustainability of agricultural production. Salt has been proven to accumulate in soil and water over time as a result of various anthropogenic activities and climatic changes. Species of the genus Salicornia thrive in the most saline environments and have a wide climatic tolerance. They can be found in a variety of subtropical, oceanic, and continental environments. This study aims to establish Salicornia europaea as a novel source of plant-based compounds that can grow in areas unsuitable for other crops. The morphological and compositional changes in the tissues of S. europaea in different consecutive developmental stages have not been investigated so far. Therefore, a comprehensive study of changes during the lifecycle of S. europaea was carried out, following changes in the plant's composition, including biomass yield, and soluble and insoluble compounds. For this, plants were cultivated in hydroponics for 15 weeks and harvested weekly to analyze biomass production, to determine soluble and insoluble compounds, protein content, and polyphenols. According to the results, glucan, xylan, and lignin increase with plant age, while water extractives decrease. Protein content is higher in young plants, while flavonoid content depends on the phenological stage, decreasing in the early flowering stage and then increasing as plants enter early senescence. Our results can aid in finding the optimal harvesting stage of S. europaea, depending on the component of interest. [ABSTRACT FROM AUTHOR]

The efficiency of the autumn wheat crop requires the application of some general technologies, but improved with innovative and specific technological sequences, depending on the evolution of the vegetation cycle and the expected production components. The researches were performed during the 2020-2022, in the experimental field of NARDI Fundulea and aimed to study the influence of agrotechnical practices on the yields and quality of wheat. The paper presents the results obtained in experiences with sowing dates and plant density, under non-irrigation condition, in the south of the country. Recording a stable and high production of autumn wheat is possible if a good sowing quality is ensured and the optimal sowing interval and plant density per m2 are observed. The variability of individual productivity of wheat plants can increase with the delay of the sowing date by up to 10-20% for the number of grains/plant and between 10-25% for the weight of grains/plant, and these lead to a decrease for production per hectare with 1000-3000 kg/ha. The variation of climatic conditions influenced negatively wheat yield and quality. [ABSTRACT FROM AUTHOR]

Background: Water availability is the key limiting factor for plant productivity in drylands covering ca. 40% of Earth's land surface. For such ecosystems to retain productivity and biodiversity under climatic change, it would be valuable to identify/promote keystone plant species that (i) have developed strategies to more efficiently utilize moisture resources not easily accessible and (ii) improve moisture conditions for neighboring plants. The very deep-rooted Ziziphus lotus, considered an ecosystem engineer, is one such example. However, it is not known which biotic traits: (a) canopy interception of moisture/rainfall, (b) hydraulic redistribution of deep ground moisture by roots, or non-biotic factors: (c) soil's volume, and (d) organic matter content, Z. lotus activates/modulates to play such a role. We, thus, selected dryland ecosystems where the plant dominates and measured for potential effects on the less deep-rooted Thymbra capitata. For assessing impacts on ecosystem productivity, we measured the spatial aggregation of ca. 3600 T. capitata plants. As a proxy for soil moisture availability and its spatial variability, we conducted a 7-year-long study using thymes' nighttime rehydration. Sampling extended up to 15 m away from Z. lotus. Results: The density of T. capitata plants growing up to 5 m around Z. lotus vs. thymes growing 10–15 m away was found significantly increased (2.5–4.5 times), while their stem/leaf moisture was ca. 10% higher at predawn compared to nightfall during the dry season. This suggests that ecosystem productivity is driven by a greater soil moisture availability around Z. lotus permitting more thyme daytime transpiration, in contrast to thymes growing further away. The phenomenon appeared only under dry topsoil (during the dry season; becoming stronger during dry years). Morning dew/rainfall interception from the canopy or soil depth/organic matter did not show significant effects, leaving only the hydraulic lift properties of Z. lotus as the most likely driver for soil moisture availability. Conclusions: The deep-rooting properties and hydraulic lift potential of Z. lotus may be the key in permitting it to boost ecosystem productivity. Such hydraulic plant traits require more attention as they may prove valuable in combating desertification and restoring ecosystems in arid/semiarid regions threatened by climate change. [ABSTRACT FROM AUTHOR]

Many temperate grasses are both hyper‐accumulators of silicon (Si) and hosts of Epichloë fungal endophytes, functional traits which may alleviate environmental stresses such as herbivore attack. Si accumulation and endophyte infection may operate synergistically, but this has not been tested in a field setting, nor in the context of changing environmental conditions. Predicted increases in atmospheric CO2 concentrations can affect both Si accumulation and endophyte function, but these have not been studied in combination.We investigated how elevated atmospheric CO2 (eCO2), Si supplementation, endophyte‐presence and insect herbivory impacted plant growth, stoichiometry (C, N, P and Si), leaf gas exchange (rates of photosynthesis, stomatal conductance, transpiration rates) and endophyte production of anti‐herbivore defences (alkaloids) of an important pasture grass (tall fescue; Lolium arundinaceum) in the field.eCO2 and Si supplementation increased shoot biomass (+52% and +31%, respectively), whereas herbivory reduced shoot biomass by at least 35% and induced Si accumulation by 24%. Shoot Si concentrations, in contrast, decreased by 17%–21% under eCO2. Si supplementation and herbivory reduced shoot C concentrations. eCO2 reduced shoot N concentrations which led to increased shoot C:N ratios. Overall, shoot P concentrations were 26% lower in endophytic plants compared to non‐endophytic plants, potentially due to decreased mass flow (i.e. observed reductions in stomatal conductance and transpiration). Alkaloid production was not discernibly affected by any experimental treatment. The negative impacts of endophytes on P uptake were particularly strong under eCO2.We show that eCO2 and insect herbivory reduce and promote Si accumulation, respectively, incorporating some field conditions for the first time. This indicates that these drivers operate in a more realistic ecological context than previously demonstrated. Reduced uptake of P in endophytic plants may adversely affect plant productivity in the future, particularly if increased demand for P due to improved plant growth under eCO2 cannot be met. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Many models are designed to generate future predictions under climate-change scenarios. Such models are typically calibrated for a study area with climate data that represent historical conditions. However, future projections of the model may include outputs for which the model has not been calibrated. Ideally, a climate-change-impacts model would be calibrated for recent conditions and also for possible future climate conditions. We demonstrate an approach, where a vegetation model is subjected to two calibrations: conventionally to the study area and separately to the study area plus additional areas representing analogues of potential future climate. We apply the dynamic vegetation model MC2 to a mountainous ecosystem in the Pacific Northwest, USA. We compare the conventional model calibration with the extra-study-area calibration and future projections. The two calibrations produce different outputs in key ecosystem variables, where some differences vary with time. Some model output trends for net primary productivity and plant functional type are more influenced by climatic input, while for others, the calibration area has greater consequence. Excluding areas representing potential future climate may be an important omission in model calibration, making the inclusion of such areas a decisive consideration in climate-change-impact simulations. [ABSTRACT FROM AUTHOR]

Climate change is an important issue that affects both global warming and precipitation, and the main cause is increased N2O emissions. Temperature and moisture are key factors in grassland ecosystem's response to climate change, and they can affect N2O fluxes. To clarify the impacts of warming and precipitation changes on N2O fluxes, an experiment was conducted in a semiarid steppe in Inner Mongolia, China over a nine‐year period (2011–2019). Plant productivity and soil nutrient dynamics were examined concurrently from 2017 to 2019, and N2O fluxes were monitored in response to different treatment conditions: control (C), warming (W), precipitation addition (P), and warming and precipitation addition (WP). The results showed that N2O emissions in the growing season were higher than those in the nongrowing season. Warming and precipitation addition had no significant effect on N2O fluxes compared with ambient conditions. Compared with P treatment, warming increased N2O flux in nongrowing season and decreased it in growing season. N2O flux was positively correlated with soil temperature and moisture (p < 0.05). Warming had a significant positive effect on soil NH4+‐N, whereas additional precipitation had a large positive effect on soil total nitrogen and soil nitrate nitrogen. With the WP treatment, soil microbial biomass nitrogen (MBN) and soil microbial biomass carbon (MBC) increased by 53.8% and 41.9%, respectively. The decrease in N2O emissions during the growing season in the W treatment compared with the P treatment may be largely attributed to the greater dominance of Leymus chinensis. The results highlight that changes in species dominance play an important role in regulating N2O emissions, and that the N2O fluxes in the nongrowing season account for a large proportion of the changes in N2O fluxes. Therefore, The warming effects on N2O emissions during nongrowing seasons should be further investigated. [ABSTRACT FROM AUTHOR]

Planting season is a decisive factor for agricultural production success. Yields of garlic culture, one of the vegetables of major demands for Cuban culinary, are very low. There are no reports of recent studies related to garlic productivity based on this factor in the literature of our country. That is why the objective of this work has been the evaluation of different planting times on the productivity of garlic (Allium sativum L.) clone 'Criollo Víctor'. The cloves were planted under semi-controlled conditions and in beds during 2019-2020 and 2020-2021 seasons in the months of September, October, November and December. The following indicators were evaluated at different times of growth: sprouting % and plant survival, plant height and the number of leaves. Once harvested (120 days after planting), the indicators evaluated were: equatorial and polar diameter of the bulb, mass of the bulb and cloves, the number of cloves and the yield (t ha-1). The results ratify October, as the optimum planting time, with greater influence of the prevailing climatic conditions on the bulb mass and percentage survival indicators. [ABSTRACT FROM AUTHOR]

Summary: A warming climate coupled with reductions in water availability and rising salinity are increasingly affecting rice (Oryza sativa) yields. Elevated temperatures combined with vapour pressure deficit (VPD) rises are causing stomatal closure, further reducing plant productivity and cooling. It is unclear what stomatal size (SS) and stomatal density (SD) will best suit all these environmental extremes.To understand how stomatal differences contribute to rice abiotic stress resilience, we screened the stomatal characteristics of 72 traditionally bred varieties. We found significant variation in SS, SD and calculated anatomical maximal stomatal conductance (gsmax) but did not identify any varieties with SD and gsmax as low as transgenic OsEPF1oe plants.Traditionally bred varieties with high SD and small SS (resulting in higher gsmax) typically had lower biomasses, and these plants were more resilient to drought than low SD and large SS plants, which were physically larger. None of the varieties assessed were as resilient to drought or salinity as low SD OsEPF1oe transgenic plants. High SD and small SS rice displayed faster stomatal closure during increasing temperature and VPD, but photosynthesis and plant cooling were reduced.Compromises will be required when choosing rice SS and SD to tackle multiple future environmental stresses. [ABSTRACT FROM AUTHOR]

Long‐term atmospheric CO2 concentration records have suggested a reduction in the positive effect of warming on high‐latitude carbon uptake since the 1990s. A variety of mechanisms have been proposed to explain the reduced net carbon sink of northern ecosystems with increased air temperature, including water stress on vegetation and increased respiration over recent decades. However, the lack of consistent long‐term carbon flux and in situ soil moisture data has severely limited our ability to identify the mechanisms responsible for the recent reduced carbon sink strength. In this study, we used a record of nearly 100 site‐years of eddy covariance data from 11 continuous permafrost tundra sites distributed across the circumpolar Arctic to test the temperature (expressed as growing degree days, GDD) responses of gross primary production (GPP), net ecosystem exchange (NEE), and ecosystem respiration (ER) at different periods of the summer (early, peak, and late summer) including dominant tundra vegetation classes (graminoids and mosses, and shrubs). We further tested GPP, NEE, and ER relationships with soil moisture and vapor pressure deficit to identify potential moisture limitations on plant productivity and net carbon exchange. Our results show a decrease in GPP with rising GDD during the peak summer (July) for both vegetation classes, and a significant relationship between the peak summer GPP and soil moisture after statistically controlling for GDD in a partial correlation analysis. These results suggest that tundra ecosystems might not benefit from increased temperature as much as suggested by several terrestrial biosphere models, if decreased soil moisture limits the peak summer plant productivity, reducing the ability of these ecosystems to sequester carbon during the summer. [ABSTRACT FROM AUTHOR]

Background: Shifts in forest phenological events serve as strong indicators of climate change. However, the sensitivity of phenology events to climate change in relation to forest origins has received limited attention. Moreover, it is unknown whether forest phenology changes with the proximity to forest edge. Methods: This study examined the green-up dates, dormancy dates, time-integrated NDVI (LiNDVI, a measure of vegetation productivity in growing season), and their sensitivities to climatic factors along the gradients of distance (i.e. proximity) to forest edge (0-2 km) in China's natural forests (NF) and planted forests (PF). For the analysis, field-surveyed data were integrated with Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI from 2000 to 2022. Results: Our results reveal that PF had earlier green-up dates, later dormancy dates, and higher LiNDVI than NF. However, green-up sensitivities to temperature were higher at the edges of NF, whereas no such pattern was observed in PF. Conversely, the sensitivity of dormancy dates remains relatively stable from the inner to the edge of both NF and PF, except for a quadratic change in dormancy date sensitivity to precipitation found in NF. Additionally, we found that the green-up sensitivity to temperature increased with decreasing proximity to edge in NF evergreen forests, while it showed the opposite trend in PF evergreen forests. Furthermore, we observed that the precipitation impact on green-up dates shifts from postponing to advancing from the inner to the edge of NF, whereas precipitation dominantly postpones PF's green-up dates regardless of the proximity to edge. The LiNDVI exhibits higher sensitivity to precipitation at the edge areas, a phenomenon observed in NF but not in PF. Conclusions: These results suggest that the responses of forests to climate change vary with the distance to the edge. With increasing edge forests, which results from fragmentation caused by global changes, we anticipate that desynchronized phenological events along the distance to the edge could alter biogeochemical cycles and reshape ecosystem services such as energy flows, pollination duration, and the tourism industry. Therefore, we advocate for further investigations of edge effects to improve ecosystem modelling, enhance forest stability, and promote sustainable tourism. [ABSTRACT FROM AUTHOR]

Drought events induced by global climate change strongly modify ecosystem structure and function in grasslands. Higher plant biodiversity can enhance ecosystem resistance to drought; however, the potential effects of drought on the relationships between above‐ground productivity (ANPP) and biodiversity along a natural aridity gradient remain poorly understood.Here, we studied the effects of experimental drought on plant community structure and ANPP during the two different dry years (2015 and 2017) spanning three temperate steppe sites with low‐, medium‐ and high‐aridity levels. We also examined the effects of drought and aridity on the associations of plant species (richness and abundance), functional (community‐weighted trait means and functional dispersion) and phylogenetic diversity (evolutionary lineages) with ANPP. A structural equation modelling (SEM) was used to elucidate how the drought affected ANPP by altering biodiversity attributes.We found that experimental drought shaped the biodiversity–ANPP relationships, and the biodiversity–ANPP relationships differed among three sites. At the low‐aridity site, ANPP was correlated with plant functional traits, whereas ANPP was correlated with functional dispersion, species and phylogenetic diversity at the medium‐aridity site. At the high‐aridity site, ANPP was correlated with species richness, functional traits and phylogenetic diversity. Compared with 2015, natural drought in 2017 strengthened the associations of species diversity, functional dispersion, leaf dry matter content and leaf nitrogen content with ANPP across three sites. SEM further showed that both experimental and natural drought directly decreased ANPP and indirectly decreased ANPP by reducing community‐weighted mean of plant height.Synthesis. These results suggest that the aridity increase or drought occurrence is likely to induce the shifts in the associations of ANPP with species and functional diversity, highlighting the important role of water availability or precipitation conditions in regulating the biodiversity–ANPP relationships in temperate steppes. Overall, functional traits related to plant size play a crucial role in modulating the response of productivity to drought across three steppe sites. Thus, to buffer the negative effects of drought on steppe ANPP should pay attention to protect the species with large plant size. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Forest ecosystems play an important role in the global carbon cycle. Clarifying the large-scale dynamics of net primary productivity (NPP) and its correlation with climatic factors is essential for national forest ecology and management. Hence, this study aimed to explore the effects of major climatic factors on the Carnegie–Ames–Stanford Approach (CASA) model-estimated NPP of the entire forest and all its corresponding vegetation types in China from 1982 to 2015. The spatiotemporal patterns of interannual variability of forest NPP were illustrated using linear regression and geographic information system (GIS) spatial analysis. The correlations between forest NPP and climatic factors were evaluated using partial correlation analysis and sliding correlation analysis. We found that over thirty years, the average annual NPP of the forests was 887 × 1012 g C/a, and the average annual NPP per unit area was 650.73 g C/m2/a. The interannual NPP of the entire forest and all its corresponding vegetation types significantly increased (p < 0.01). The increase in the NPP of evergreen broad-leaved forests was markedly substantial among forest types. From the spatial perspective, the NPP of the entire forest vegetation gradually increased from northwest to southeast. Over the years, the proportions of the entire forest and all its corresponding vegetation types with a considerable increase in NPP were higher than those with a significant decrease, indicating, generally, improvements in forest NPP. We also found climatic factors variably affected the NPP of forests over time considering that the rise in temperature and solar radiation improved the interannual forest NPP, and the decline in precipitation diminished the forest NPP. Such varying strength of the relationship between the interannual forest NPP and climatic factors also varied across many forest types. Understanding the spatiotemporal pattern of forest NPP and its varying responses to climatic change will improve our knowledge to manage forest ecosystems and maintain their sustainability under a changing environment. [ABSTRACT FROM AUTHOR]

Understanding how functional traits influence community assemblage and functioning is crucial for assessing the effects of global change on vegetation composition. We studied the functional composition (i.e., plant size (SIZE), leaf area (LA), specific leaf area (SLA), and leaf dry matter content (LDMC)) of a xerophile pasture and a mesophile grassland in southern Italy, and recorded species richness (SR), plant cover (COV) and flowering rates (FLOW) over a 7-year period. Both communities revealed the dominance of stress-tolerators, probably reflecting an adaptation to the Mediterranean climate. The functional classification of species distinguished three groups. Species from the mesophile community had larger SIZE and LA, while those from the xerophile pasture showed higher LDMC; SLA was not connected to the source community. Community-level analyses confirmed such patterns, but with higher SLA in the mesophile grassland. While SR was comparable, COV and FLOW varied between the communities. At the species level, LDMC was positively related to FLOW and the inter-annual variability of COV and FLOW. At the community level, SIZE, LA and SLA were positively related to COV, while LDMC was positively related to FLOW. Trait variations can significantly contribute to the xerophile–mesophile shift in Mediterranean mountain vegetation, by regulating the productivity of species and communities in the two contexts and, possibly, their responsiveness to global change. [ABSTRACT FROM AUTHOR]

Tetrapyrrole biosynthesis produces metabolites that are essential for critical reactions in photosynthetic organisms, including chlorophylls, heme, siroheme, phytochromobilins, and their derivatives. Due to the paramount importance of tetrapyrroles, a better understanding of the complex regulation of tetrapyrrole biosynthesis promises to improve plant productivity in the context of global climate change. Tetrapyrrole biosynthesis is known to be controlled at multiple levels—transcriptional, translational and post-translational. This review addresses recent advances in our knowledge of the post-translational regulation of tetrapyrrole biosynthesis and summarizes the regulatory functions of the various auxiliary factors involved. Intriguingly, the post-translational network features three prominent metabolic checkpoints, located at the steps of (i) 5-aminolevulinic acid synthesis (the rate-limiting step in the pathway), (ii) the branchpoint between chlorophyll and heme synthesis, and (iii) the light-dependent enzyme protochlorophyllide oxidoreductase. The regulation of protein stability, enzymatic activity, and the spatial organization of the committed enzymes in these three steps ensures the appropriate flow of metabolites through the tetrapyrrole biosynthesis pathway during photoperiodic growth. In addition, we offer perspectives on currently open questions for future research on tetrapyrrole biosynthesis. [ABSTRACT FROM AUTHOR]

As arctic permafrost continues to thaw, previously inaccessible nitrogen (N) becomes available to N‐limited arctic plants. Increased N availability could enhance plant growth and thereby potentially offset climate‐induced carbon release. Arctic plants can take up newly available permafrost‐N locally upon release. However, in a topographically diverse arctic landscape, permafrost‐N may be transported along hillslopes, away from the point‐of‐release. The extent to which topographical N transport can impact arctic vegetation change depends on whether N is retained locally, captured by downslope recipient plant communities, or transported away.We used stable isotope labelling (15N) to simulate upslope release of ammonium (NH4+) and nitrate (NO3−) from thawing permafrost on an arctic hillslope, western Greenland. We tracked the plant species‐specific uptake of simulated permafrost‐released N from the upslope point‐of‐release to the bottom of the slope through 4 years.We found that arctic tundra plants successfully acquired locally released permafrost‐N, even in sloping terrain, and that N was strongly retained in the plant–soil system through multiple years. At the same time, we also importantly demonstrate that permafrost‐N can be transported and taken up by plants up to 30 m downslope from the point‐of‐release. Especially NO3− was more easily redistributed vertically within the soil column compared to NH4+ and therefore potentially more accessible to plants. Specifically, plant species with fast N uptake capacity and deep‐soil foraging strategies may have competitive advantages for capitalising on deep‐soil released and topographically transported permafrost‐N (here exemplified by Equisetum arvense and Salix glauca). Nevertheless, even mosses gained access to permafrost‐N via vertical and lateral redistribution on the slope. Ultimately, the intricate balance between strong local N retention, downslope transport and plant species‐specific uptake strategies may contribute to shaping arctic vegetation change.Synthesis. Across spatially complex arctic ecosystems, arctic plants can take up permafrost‐released N both at the local point‐of‐release and at a considerable distance downslope. The potential for arctic plants to take advantage of topographically transported permafrost‐N could lead to long‐term and landscape‐scale changes in species composition, plant productivity, and ultimately carbon and climate feedbacks across the Arctic. [ABSTRACT FROM AUTHOR]

Understanding the importance of temperature and precipitation on plant productivity is beneficial, to reveal the potential impact of climate change on vegetation growth. Although some studies have quantified the response of vegetation productivity to climate change at local, regional, and global scales, changes in climatic constraints on vegetation productivity over time are not well understood. This study combines the normalized difference vegetation index (NDVI) and the net primary production (NPP) modeled by CASA during the plant-growing season, to quantify the interplay of climatic (growing-season temperature and precipitation, GST and GSP) constraints on alpine-grassland productivity on the Tibetan Plateau, as well as the temporal dynamics of these constraints. The results showed that (1) 42.2% and 36.3% of grassland NDVI and NPP on the Tibetan Plateau increased significantly from 2000 to 2019. GSP controlled grassland growth in dryland regions, while humid grasslands were controlled by the GST. (2) The response strength of the NDVI and NPP to precipitation (partial correlation coefficient RNDVI-GSP and RNPP-GSP) increased substantially between 2000 and 2019. Especially, the RNDVI-GSP and RNPP-GSP increased from 0.14 and 0.01 in the first 10year period (2000–2009) to 0.83 and 0.78 in the second 10-year period (2010–2019), respectively. As a result, the controlling factor for alpine-grassland productivity variations shifted from temperature during 2000–2009 to precipitation during 2010–2019. (3) The increase in precipitation constraints was mainly distributed in dryland regions of the plateau. This study highlights that the climatic constraints on alpine-grassland productivity might change under ongoing climate change, which helps the understanding of the ecological responses and helps predict how vegetation productivity changes in the future. [ABSTRACT FROM AUTHOR]

Summary: Agriculture faces the considerable challenge of having to adapt to a progressively changing climate (including the increase in CO2 levels and temperatures); environmental impact must be reduced while at the same time crop yields need to be maintained or increased to ensure food security. Under this scenario, increasing plants' nitrogen (N) use efficiency and minimizing the energy losses associated with photorespiration are two goals of crop breeding that are long sought after. The plastidic glutamine synthetase (GS2) enzyme stands at the crossroads of N assimilation and photorespiration, and is therefore a key candidate for the improvement of crop performance. The GS2 enzyme has long been considered essential for angiosperm survival under photorespiratory conditions. Surprisingly, in Arabidopsis GS2 is not essential for plant survival, and its absence confers tolerance towards ammonium stress, which is in conflict with the idea that NH4+ accumulation is one of the main causes of ammonium stress. Altogether, it appears that the 'textbook' view of this enzyme must be revisited, especially regarding the degree to which it is essential for plant growth under photorespiratory conditions, and the role of NH4+ assimilation during ammonium stress. In this article we open the debate on whether more or less GS2 is a desirable trait for plant productivity. [ABSTRACT FROM AUTHOR]

Land plants are constantly subjected to multiple unfavorable or even adverse environmental conditions. Among them, abiotic stresses (such as salt, drought, heat, cold, heavy metals, ozone, UV radiation, and nutrient deficiencies) have detrimental effects on plant growth and productivity and are increasingly important considering the direct or indirect effects of climate change. Plants respond in many ways to abiotic stresses, from gene expression to physiology, from plant architecture to primary, and secondary metabolism. These complex changes allow plants to tolerate and/or adapt to adverse conditions. The complexity of plant response can be further influenced by the duration and intensity of stress, the plant genotype, the combination of different stresses, the exposed tissue and cell type, and the developmental stage at which plants perceive the stress. It is therefore important to understand more about how plants perceive stress conditions and how they respond and adapt (both in natural and anthropogenic environments). These concepts were the basis of the Special Issue that International Journal of Molecular Sciences expressly addressed to the relationship between environmental stresses and plants and that resulted in the publication of 5 reviews and 38 original research articles. The large participation of several authors and the good number of contributions testifies to the considerable interest that the topic currently receives in the plant science community, especially in the light of the foreseeable climate changes. Here, we briefly summarize the contributions included in the Special Issue, both original articles categorized by stress type and reviews that discuss more comprehensive responses to various stresses. [ABSTRACT FROM AUTHOR]

Drought is one of the most important natural hazards impacting ecosystem carbon cycles. However, it is challenging to quantify the impacts of drought on ecosystem carbon balance and several factors hinder our explicit understanding of the complex drought impacts. First, drought impacts can have different time dimensions such as simultaneous, cumulative, and lagged impacts on ecosystem carbon balance. Second, drought is not only a multiscale (e.g., temporal and spatial) but also a multidimensional (e.g., intensity, time‐scale, and timing) phenomenon, and ecosystem production and respiration may respond to each drought dimension differently. In this study, we conducted a comprehensive drought impact assessment on ecosystem productivity and respiration in humid regions by including different drought dimensions using global FLUXNET observations. Short‐term drought (e.g., 1‐month drought) generally did not induce a decrease in plant productivity even under high severity drought. However, ecosystem production and respiration significantly decreased as drought intensity increased for droughts longer than 1 month in duration. Drought timing was important, and ecosystem productivity was most vulnerable when drought occurred during or shortly after the peak vegetation growth. We found that lagged drought impacts more significantly affected ecosystem carbon uptake than simultaneous drought, and that ecosystem respiration was less sensitive to drought time scale than ecosystem production. Overall, our results indicated that temporally‐standardized meteorological drought indices can be used to reflect plant productivity decline, but drought timing, antecedent, and cumulative drought conditions need to be considered together. Plain Language Summary: Drought has not only simultaneous impacts but also cumulative and lagged impacts on ecosystem carbon cycles. In addition, different drought intensity, time‐scale, and timing may impact ecosystem production and respiration differently. Those multiple dimensions of drought have made the accurate drought impact assessments on ecosystem carbon cycles challenging. Our study provided a comprehensive quantification of various drought dimensions on ecosystem production and respiration using global flux tower observations and multiple time scales of one widely used drought index. Our results indicated that drought timing, lagged impacts, and long‐term drought intensity are the most significant drought dimensions impacting ecosystem carbon uptake. We found that while most earlier drought studies focus on the impacts of simultaneous drought, the lagged drought impacts are more significantly impacting ecosystem carbon uptake. Ecosystem respiration and production showed different sensitivity to drought cumulative impacts. Drought has the greatest effect on vegetation during and shortly after the peak of the growing season. These results help us to reconsider the impacts of drought on ecosystem carbon uptake by incorporating all the significant factors to provide a more accurate estimation and prediction of drought impacts. Key Points: Lagged drought impacts are more significantly impacting ecosystem carbon uptake than simultaneous drought impactsShort‐term drought generally does not induce plant productivity decrease in humid regionsEcosystem productivity is most sensitive to drought that occurs shortly after the peak stage of the growing season [ABSTRACT FROM AUTHOR]

Selection criteria that co-optimize water use efficiency and yield are needed to promote plant productivity in increasingly challenging and variable drought scenarios, particularly dryland cereals in the semi-arid tropics. Optimizing water use efficiency and yield fundamentally involves transpiration dynamics, where restriction of maximum transpiration rate helps to avoid early crop failure, while maximizing grain filling. Transpiration restriction can be regulated by multiple mechanisms and involves cross-organ coordination. This coordination involves complex feedbacks and feedforwards over time scales ranging from minutes to weeks, and from spatial scales ranging from cell membrane to crop canopy. Aquaporins have direct effect but various compensation and coordination pathways involve phenology, relative root and shoot growth, shoot architecture, root length distribution profile, as well as other architectural and anatomical aspects of plant form and function. We propose gravimetric phenotyping as an integrative, cross-scale solution to understand the dynamic, interwoven, and context-dependent coordination of transpiration regulation. The most fruitful breeding strategy is likely to be that which maintains focus on the phene of interest, namely, daily and season level transpiration dynamics. This direct selection approach is more precise than yield-based selection but sufficiently integrative to capture attenuating and complementary factors. [ABSTRACT FROM AUTHOR]

Summary: It is a grand challenge to ensure the food security for a predicted world population of exceeding 9.7 billion by 2050, especially in an era of global climate change, land degradation and biodiversity loss. Current agricultural productions are mainly relying on synthetic chemical fertilisers to boost plant productivity but have undesirable effects on the environment and soil biodiversity. A promising direction in sustainable agriculture is to harness naturally occurring processes of beneficial plant‐associated microbiomes to ensure sustained crop production and global food security. Despite the significant progress made in the development of beneficial microbes as inoculants to enhance plant performance, challenges remain with the translation of knowledge of plant and soil microbiomes to successful microbial products in the agricultural sector. Here, we highlight how fertilizer technology should be renovated by harnessing microbiome‐based innovations to promote plant productivity and contribute to the end of hunger. [ABSTRACT FROM AUTHOR]

Agricultural systems are constantly under environmental pressure, and the continuous rise of the global population requires an increasingly intensification of agronomical productivity. To meet the current global food demand, particularly in depleted ecosystems under adverse climate conditions, the development of novel agronomical practices, which ensure crop productivity while safeguarding minimal impact to the environment, must be encouraged. Since aluminium (Al), cobalt (Co), selenium (Se), silicon (Si) and sodium (Na) are not essential to plant metabolism, their benefits are often neglected or underestimated in agriculture; however, several studies support their advantages in sustainable agriculture when properly employed. The agronomical uses of these elements have been studied in the last decades, delivering important cues for the improvement of food and feed production worldwide due to beneficial effects in plant growth and productivity, nutrient balance, pest and pathogen resistance, water stress management, heavy-metal toxicity alleviation, and postharvest performance. However, their application has not been addressed as part of a holistic conservation strategy that supports the sustainability of agroecosystems. Here, we discuss the potential use of these elements in sustainable agriculture, and the knowledge gaps that hinder their effective integration into agronomical practices, which result in equally profitable applications while supporting environmental sustainability. [ABSTRACT FROM AUTHOR]