Search

Much attention has been given to the large-scale anthropogenic influence on extreme temperature changes. However, the possible effects of atmospheric factors and the role of the locally anthropogenic driver on the observed regional change in extreme temperatures have not been well understood. Datasets of the China Meteorological Administration (CMA) were used to examine the possible influence. The data include the homogenized surface air maximum/minimum temperature, surface sunshine duration (SSD), water vapor pressure (VAP), and total cloud cover (CLO) during 1961–2020. We calculated the seasonal means of maximum temperature (Tx (mean)), minimum temperature (Tn (mean)) and diurnal temperature range (DTR) to analyze the characteristics of extreme surface air temperature (ESAT) changes in winter and summer, and their relationship to SSD, VAP , and CLO , as well as the urbanization effect in the extreme temperature indices series. The changes in the trends for SSD and VAP were more closely correlated with ESAT in winter and summer, respectively. The decreasing of SSD led to a slowing of the ESAT warming, while an increase of the VAP led to the intensification of ESAT warming. In addition, CLO also had an important role in the change of ESAT. The seasonal mean correlation coefficient over China mainland between Tn (mean) and VAP were statistically significant and higher than those with SSD and CLO. The seasonal mean correlation between Tx (mean) / DTR and SSD were also statistically significant. The SSD and VAP strongly influenced the Tx (mean) in winter. The urbanization contribution to the DTR trends reached >25% in both winter and summer. SSD strongly influenced the trend of ESAT in urban area whereas CLO/VAP had larger influence on the trend of ESAT in rural area, which were all related to the urbanization effect as observed in the data series. • The decreasing of sunshine duration and increasing of the water vapor led to a slowing and the intensification of the extreme temperature warming, respectively. • The correlation coefficient between minimum temperature and water vapor were statistically significant. The correlation between maximum temperature / diurnal temperature range and sunshine duration were statistically significant. • The trend of sunshine duration strongly influenced on the trend of extreme temperature in urban area, whereas the trend of cloud cover and water vapor had more influence in rural area. [ABSTRACT FROM AUTHOR]

The heart of biogas industry is on, with going on transformation and upgrading. Upgraded biogas, namely biomethane, is a low-carbon, clean, safe and efficient renewable energy, which very often has been neglected in energy debate. However, it shows great contributions to promoting the transformation and upgrading of energy structure and energy security, building an ecological civilization, etc. The successful business cases in Europe have displayed many reasons to keep developing this sector. Hence, taking China as an example, this work aims to benefit the government and energy transition stakeholders more broadly in working together to enable and manage successful biogas industry transition with the experience of European countries. This includes how policymakers can help to guarantee the healthy development of biomethane industry, and what the government and companies can do to boost the market, economy and technology of biomethane. The ultimate target is to prosper the world's biomethane industry to meet people's ever-growing demands for a better life and a beautiful environment. • Biomethane industry is the inevitable way of biogas industry development. • The future direction of biomethane industry should include energy, environment and human health. • Biomethane industry needs to innovate on the existing biogas industry. • The top-level design needs to be in place, and detailed policies need to follow. [ABSTRACT FROM AUTHOR]

• Home-visiting interventions have positive effects on child cognitive development, parenting beliefs and parenting practices of caregivers in rural China. • Home-visiting interventions have null effects on child social-emotional development in rural China. • Three mechanisms are identified through which interventions are able to raise child cognitive development. • Shifting parenting beliefs; increasing parenting practices; and shifting parenting beliefs thus fostering better parenting practices of primary caregivers are the three mechanisms that are driving our overall results of the impact of home-visiting interventions on early child development. To better understand the impacts of parenting interventions (e.g., parental training of psychosocial stimulating activities) on child developmental outcomes and design effective policies to benefit young children, it is essential to identify the mechanisms through which the interventions work. To this end, this paper presents the results of two randomized controlled trials that offered home visitation, parenting trainings to 435 households (with 527 households as the control group) in 174 villages across three provinces in China. The findings from the randomized controlled trials showed that the interventions significantly improved child cognitive development and had a positive effect on the primary caregivers' parenting practices and their parenting beliefs. The analysis suggests three possible mechanisms through which the parenting interventions affected child cognitive development: changing the parenting beliefs of the primary caregivers, shifting the parenting practices of the primary caregivers, and improving the primary caregivers' parenting beliefs, thus fostering better parenting practices. [ABSTRACT FROM AUTHOR]

Background: Social-emotional development during the first three years of life is associated with later social-emotional development and cognitive development. In rural China, research has found large shares of children under age three are developmentally delayed, yet little is known about the paths of social-emotional development before age 3 or how developmental paths predict later social-emotional skills and cognitive skills.Aims: To investigate the paths of child social-emotional development during ages 0-3 and examine how different paths predict social-emotional development and cognitive development at preschool age.Methods: Three waves of longitudinal panel data from 1245 children in rural Western China was collected. Child social-emotional development was measured by the Ages and Stages Questionnaire: Social-Emotional. Child cognitive development was measured by the Bayley Scales of Infant Development and by the Wechsler Preschool and Primary Scale of Intelligence-Fourth Edition. Four paths of child social-emotional development were classified: "never" social-emotionally delayed; "persistently" social-emotionally delayed; "improving," or "deteriorating."Results: 331 (27%) were never social-emotionally delayed; 373 children (30%) were persistently social-emotionally delayed; 149 children (12%) experienced improving social-emotional development; and 392 children (31%) experienced deteriorating social-emotional development. Children who were never social-emotionally delayed or who were on an "improving" path had higher social-emotional development at preschool age (p < .01). Children who were persistently social-emotionally delayed (p < .5) and on a deteriorating path (p < .01) had lower social-emotional development at preschool age. Children on the persistently delay path also were shown to have lower levels of cognitive development at preschool age (p < .01).Conclusions: Different paths of child social-emotional development before age 3 are associated with different social-emotional and cognitive development at preschool age. [ABSTRACT FROM AUTHOR]

Promoting the biomass industry in China would provide significant ecological, economic, and societal benefits by ameliorating soil and groundwater pollution and providing a sustainable energy source. However, although there is great potential for expanding the biomass industry in China, it currently faces large obstacles, with respect to its utilization, low economic performance, and other limitations. This study conducts a comprehensive literature review on biomass utilization methods, and establishes a new recycling model that couples the use of anaerobic digestion (AD) and its byproducts with biochar. In the model, biomass waste is used for biogas and biochar production, and biogas residues are further cracked into biochar. Biochar is also used as an additive to modify the AD process and promote methane production. In addition to its single application, biochar is further used in combination with biogas slurry or residue as a soil conditioner to repair soil and promote the growth of crops. This circulation model differs from models in which biomass alone is used in biogas or biochar production, and it combines all processes to promote the use of biomass, increase its conversion efficiency and strength the applications of such processes in the agricultural sector. Previous reports have shown that each part of the model can play a positive role in improving overall efficiency. Therefore, the application of the combined circulation model would be beneficial in biomass utilization and as such is a promising method for promoting the sustainable development of energy and agriculture in China, while protecting the environment. • Biomass waste is used for biogas and biochar production. • Biochar is effective to modify the AD process and promote methane production. • Biogas residues are further cracked into biochar. • Biochar combined with biogas slurry or residue can serve as a soil conditioner. • A new recycling model is established by coupling biochar with anaerobic digestion. [ABSTRACT FROM AUTHOR]

• Introduce an evaluation approach for the Ecological Service Value of Water (ESV-W). • Improve the assessment of Ecosystem Services Value (ESV) by introducing the Agricultural Price Index (API) into the Equivalence Factor (EF). • Improve the Water Allocation and Simulation Model (WAS) to simulate and quantify the 'natural-artificial' soil water cycle. • Analysis of the ESV and ESV-W in the Yangtze River Basin from 2005 to 2020. This paper introduces an evaluation approach for the Ecological Service Value of Water (ESV-W) by coupling the assessment of Ecosystem Services Value (ESV) with the Water Allocation and Simulation Model (WAS). The proposed method is applied to evaluate ESV and ESV-W in the Yangtze River Basin from 2005 to 2020. Firstly, an improved Equivalence Factor (EF) method is employed to estimate ESV by considering different land use types and service categories. Then, the enhanced WAS model is used to quantify and identify the role of the 'natural-artificial' soil water cycle in supporting the ecological service functions. Finally, by integrating the ESV evaluation system with the WAS model, the evaluation method for ESV-W is established. The results indicated that from 2005 to 2020, the total ESV increased from 4.0 to 5.6 trillion US Dollars, with forests being the primary contributor among land use types (about 52%), and regulating services are dominating among service categories (about 70%). The spatial distribution of the ESV showed a decreasing trend from southeast to northwest in the Yangtze River Basin, while the ESV-W exhibited high values concentrated along the main stream of the upper reaches of the Yangtze River and lower in the middle. The ESV-W of the 'natural' soil water cycle still dominates (over 96%), but the ESV-W of the 'artificial' soil water cycle has been rapidly increasing in recent years. In 2020, the ESV-W per unit water of precipitation, irrigation, and ecological water were 4.0 Dollars/ m 3 , 0.7 Dollars/ m 3 , and 32.4 Dollars/ m 3 , respectively. This study aims to provide references for the protection of water ecosystems and the sustainable utilization of water resources. It also serves as a reference for improving the evaluation system of ESV. [ABSTRACT FROM AUTHOR]

Grazing has a profound impact on the availability of soil resources like carbon (C), nitrogen (N), and phosphorus (P) in grasslands. These changes can potentially make it difficult to meet microbial elemental demands, thus affecting microbial C use efficiency (CUE) and soil C dynamics. Nevertheless, it remains unclear how soil microbes respond to stoichiometric imbalances and their consequent effect on microbial CUE. In this study, we investigated the stoichiometry of soil labile resources, microbial biomass, extracellular enzymes, as well as the microbial community composition and microbial CUE, microbial respiration, microbial quotient (q MB), and soil organic carbon (SOC) changes, at sites with four grazing intensities (no grazing, light, medium, and heavy grazing) in a temperate steppe of northern China. Grazing led to decreased stoichiometric imbalances between soil labile resources and microbial biomass, thereby exacerbating limitations of available C on soil microbes. To alleviate this limitation of C, microbes raised the microbial threshold elemental ratios and microbial biomass, and increased fungi dominance rather than increased activities of C-, N-, and P- acquiring enzymes due to increased microbial own growth. Microbes also improved microbial CUE, q MB, and microbial respiration while decreasing SOC under increasing grazing intensity. These integrated adaptations denote that grazing can reduce SOC which is closely affected by soil microbial C utilization induced by resource change conditions despite the increased microbial biomass contribution to SOC. These findings illustrate the regulation of stoichiometric imbalances in soil C dynamics driven by microbes under grazing and improve our understanding of how stoichiometric changes influences soil C flows in semi-arid grassland. [Display omitted] • Grazing lowered stoichiometric imbalances but increased microbial C limitation. • Microbes decreased C-, N-, P-acquiring enzymes for limiting nutrients acquisition. • Microbes increased their biomass, threshold elemental ratios, and fungi:bacteria. • Aggravated grazing induced increased CUE, q MB, and microbial own growth. • Adaptative pathways of microbes resulted a decline of SOC. [ABSTRACT FROM AUTHOR]

• Teacher qualifications are significantly correlated to preschool child development. • Teacher education level is highly associated with preschool child development. • Teacher professional ranking is highly associated with preschool child development. • Teacher experience has no relation to preschool child development. • Teacher training has no relation to preschool child development. In the preschool period, interactions between teachers and children are an essential input for healthy development. However, it is not well understood how the qualifications of preschool teachers contribute to child development during the preschool period, and previous international studies have returned mixed results. We drew on data from a longitudinal study of 1031 preschool children age 49–65 months in rural China to examine the associations between teacher qualifications and the development of preschool children. The findings showed that 36% of preschool children in the sample are developmentally delayed. Overall, teacher qualifications (education level, specialization in early childhood education, professional ranking, experience and training) were significantly associated with preschool-age child developmental outcomes. Teacher professional ranking and educational attainment were positively and significantly correlated with two measures of child language development, but a degree specialized in early childhood education was negatively related to vocabulary acquisition. No significant correlations were found between teacher experience or teacher training and child developmental outcomes. The study concludes that policymakers should encourage highly educated and professionally ranked teachers to serve in rural preschools in order to improve the development of preschool children. [ABSTRACT FROM AUTHOR]

Seismic hazards and risks around an individual fault can be assessed from complementary paleoseismic data. A high-resolution sediment core recovered from the Yileimu Lake revealed 11 potential paleoearthquakes around the Fuyun fault in northern Xinjiang. Among them, three events recorded by ductile deformation and turbidites or coseismic subsidence were possibly correlated with M s ≥ 7.0 earthquakes, and the others characterized by turbidites or coarse deposits were likely related to M s ≥ 5.8 or M s ≥ 5.5 earthquakes. Shaking intensities of 8.60 and 5.51 MMI were required to cause extensive landslides and turbidites, respectively; while 6.89, 6.35 and 5.34 MMI were likely to be required to cause coseismic subsidence, ductile deformation and coarse deposits related to landscape shattering in the catchment area, respectively. Absolute radiocarbon dating and historical earthquake-event markers disclosed a recurrence interval of 20–60 years for M s ≥ 5.5 earthquakes, and a potential interval of 100 years for M s ≥ 7.0 earthquakes during the last 450 years. A seismic quiescence of 89 years since the 1931/08/11 M s 8.0 Fuyun earthquake might have significantly increased the potential of a strong earthquake related to the fault in the near future. • Lake sediments recorded 11 potential paleoearthquakes around the Fuyun fault. • Intensities and magnitudes for distinct sedimentary events were distinguished. • Recurrence intervals for earthquakes with different magnitudes were proposed. [ABSTRACT FROM AUTHOR]

Ecological security (ES) can express the health and integrity of regional ecosystems; hence, a better understanding of regional ES levels and their influencing factors can help to specify sustainable ecological management policies. Levels of ES in the West Liao River Basin were computed for the years of 2000 to 2020 at both the grid and county scale by using the pressure–state–response model, with ecosystem services also included in the assessment system. From 2000 to 2020, the area of both the forests and grasslands increased, due to the Grain for Green Project, which augmented net primary productivity (NPP), an ecosystem production service, and enhanced the overall habitat quality of the basin and promoted improvements to the regional ecological environment. The ES levels in most areas of the West Liao River Basin were improved over time, in that >90% of its area was above the middle level in 2020. The coordinates of "very insecure" moved to the basin's southeast, while "very secure" moved to its northwest, which indicated serious ES problems in the southeast of the basin. When compared with the most economically developed areas or remote areas having societal progress and human activities, generally the moderately developed areas have better ES levels. Further, human factors are more important to ES than natural factors, though all driving factors had enhanced impacts on the change in ES via their interactive effects. By determining the ES levels of the basin, four ecological management zones were then derived for it. We identified the main environmental problems in each ecological management zones and put forward the corresponding management measures, which would make the results more useful for supporting resource management and ecological protection of ecologically fragile areas in the agriculture and pasture interlaced landscape of northern China. • Ecological security levels were improved in most areas of the West Liao River Basin. • Moderately developed areas have better ecological security levels. • From 2000 until 2020, the gravity center of ecological security changed. • Human factors are more important to ecological security than natural factors. • Including ecosystem services can better quantify the ecological security status. [ABSTRACT FROM AUTHOR]

Anthropogenic activities have made phosphorus (P) a new sustainability issue globally. To better understand the mechanisms of soil P dynamics responding to inorganic P fertilization (0–12.5 g P m−2yr−1), we conducted a 2-year field experiment in a temperate grassland in northern China. The P fertilizer was added once per year before the growth period as NaH 2 PO 4. We randomly collected topsoil samples (0–10 cm) and analyzed the soil properties, microbial community, and extracellular enzyme activities, and quantified the soil P fractions using solution 31P nuclear magnetic resonance (31P NMR) spectroscopy. P application promoted transformation from organic P to inorganic P driven by microbial carbon (C) demand and regulated by altered soil properties and microbial characteristics. P addition decreased orthophosphate diesters, especially DNA, due to increased hydrolysis under increased soil pH. This may increase hydrolysates such as α - glycerophosphate and choline phosphate. Orthophosphate monoesters, especially myo -inositol hexaphosphate, also decreased following increased P availability. This could be explained by increased alkaline phosphatase activity and reduced sorption due to a decreased metal (Ca, Al, and Fe) content. Furthermore, P fertilization increased soil NH 4 +-N, thereby increasing the growth of phosphonate-solubilizing microorganisms (Bacillus, Streptomyces, Bradyrhizobium, Mesorhizobium, Penicillium, Aspergillus , and Fusarium). Their increased growth also contributed to inorganic P solubilization and organic P mineralization due to their P-solubilizing specificity. Together, these factors increased inorganic P, especially orthophosphate, which was temporarily immobilized in microbial cells, to regulate the soil-solution P supply, and created a potentially available P sink in the grassland. • Microbial C demand drove transformations from organic P to inorganic P. • Increased soil pH stimulated the hydrolysis of diesters, especially DNA. • Monoesters decreased due to altered alkaline phosphatase activity and metal content. • Soil NH 4 +-N stimulated the growth of phosphonate-solubilizing microorganisms. • Orthophosphate immobilized in microbes regulated the soil solution's P supply. [ABSTRACT FROM AUTHOR]

• We use five-wave panel datasets to examine the effects of maternal migration on children's cognition. • The cognition developments were measured by BSID-I and WPPSI-VI. • Maternal migration has negative effects on the cognition of preschool-aged children. • Possible mechanisms include a generational shift in parenting and feeding practices. Preschool-aged children account for over 38 per cent of those left behind. Previous research suggests that maternal migration during early childhood may create a greater negative impact, however, the literature on the effect of maternal migration on cognitive development of preschool aged children is rare. This study uses a unique panel dataset following children from infancy to 63 months and their caregivers to estimate the causal effects of maternal migration on the critical cognitive development of children left behind. We find that maternal migration increases the probability of cognitive delay by six percentage points. Possible mechanisms include a generational shift in parenting and feeding practices leading to reduced engagement in stimulating activities and dietary diversity. To the best of our knowledge, this is the first study to examine the causal effects of maternal migration on cognition during the first six years of life in rural China. [ABSTRACT FROM AUTHOR]

• P limitation under grazing was driven by plant compensatory growth and soil P loss. • Available P concentration in the rhizosphere was increased under grazing. • Plant requirement for P stimulated its transition from organic into inorganic P. • LMWOAs and mycorrhizal fungi mobilized the rhizosphere P. • A medium grazing intensity is conducive to grassland's sustainable development. Soil erosion and phosphorus (P) removal due to livestock production have led to a grave depletion of P in grasslands. Accordingly, understanding how plants cope with such P limitation conditions and which P transition processes operate in the soil under different grazing intensities is imperative for better scientific management of grazed grasslands. Here, we conducted a field experiment that tested the impact of different grazing intensities (light, medium, and heavy) and a control (no grazing) on P-related dynamics in a typical temperate grassland site in Inner Mongolia, China. The increased N:P ratio in leaves of dominant plant species and higher annual primary production (APP) of vegetation that generally ensued under grazing indicated that plants' compensatory growth in response to grazing pressure was a factor contributing to P limitation. Plants' P requirement for growth stimulated P transition in the rhizosphere via the mobilization of low-molecular-weight organic acids (LMWOAs) and mycorrhizal fungi. Specifically, LMWOAs promoted the conversion of stable P into organic P, and mycorrhizal fungi converted that organic P into labile P in the rhizosphere. This P transition process is jointly affected by changes to key soil physiochemical properties and the altered P input from excrement caused by herbivores. Altogether, these results suggest that grazing increases the biological vitality of the soil and accelerates the transition of P in the rhizosphere; and a medium grazing intensity may be more suitable for agricultural production because it provides the highest APP and a more biologically dynamic soil environment. [ABSTRACT FROM AUTHOR]

Anthropogenic activities have increased ecosystem phosphorus (P) inputs and have affected terrestrial ecosystem carbon (C) cycles. However, the fate of soil organic C (SOC) under P addition remains elusive, and the potential mechanisms underlying plant-microbial linkages mediated SOC formation and decomposition are poorly understood. Here, we conducted a field P fertilization experiment to explore the effects on SOC dynamics in a typical temperate grassland in northern China. P addition increased soil P availability and pH, thereby stimulating plant nutrient uptake and growth, leading to higher C inputs to soils via plant biomass (shoots, litter and roots). However, P addition exacerbated microbial N limitation, altered microbial community composition (with a lower fungal to bacterial ratio), shifted microbial life-history strategies, which transitioned from the K -strategy (Acidobacteria, Chloroflexi, and Verrucomicrobia dominant) to the r - strategy (Proteobacteria, Bacteroidetes, and Firmicutes dominant), and modulated their functional characteristics. All of these factors regulated microbial substrate preferences and changed the C components that undergo decomposition. These changes ultimately accelerated the utilization of active C, hampered passive C decomposition, and helped to create a longer-term stable C sink in the grassland. • P addition decreased active C and increased passive C and this resulted in a net increase of SOC. • Increased plant productivity and litter quality improved plant C inputs to the soil. • Altered microbial characteristics regulated their substrate preference, thus stimulating active C loss. • Decreased soil metallic elements may partially weaken the stability of SOC. • Accumulated passive C would be beneficial in creating a longer-term stable C sink. [ABSTRACT FROM AUTHOR]

Carbon (C) assimilation and allocation play a crucial role in determining plant responses to environmental stress such as herbivory. However, the pattern how these grasses allocate assimilated C under increasing herbivory intensity hasn't been fully understand. In this study, we quantified photosynthetic C assimilation and allocation of newly assimilated C among tissues and metabolic processes (structural growth, storage, and defense) under different grazing intensities using 13C tracing of a dominant grass species, Leymus chinensis. Light grazing promoted utilization of newly-assimilated 13C (more than 90% 13C allocated to aboveground tissues on first day after labeling), photosynthetic rate, and reduced mean residence time of 13C of L. chinensis. The photosynthetic capacity and regulation of chlorophyll fluorescence thereby C assimilation were constrained under medium and heavy grazing. Light grazing also increased accumulation of non-structural carbohydrates (NSC) in stems for energy supply to leaf regeneration. As herbivory pressure increased, 13C tracing showed preferential allocation of newly assimilated C to belowground tissues (16–27% 13C on first day after labeling), while upregulating leaf defenses by increasing secondary metabolites and in root storage by NSC accumulation. Although the significant changes showed in C allocation to storage and secondary metabolism of L. chinensis , there are no difference in structural growth (defined as structural biomass= biomass - NSC – secondary metabolites) among grazing intensities. Overall, L. chinensis adopted a conservative C-allocation strategy (upregulated C storage and secondary metabolism) that emphasized long-term survival under increasing herbivory. Light grazing was an optimal grazing intensity that promoted structural growth and C allocation of L. chinensis , which could sustain and even increase grassland productivity. These characteristics of the plant's C allocation strategy provide new insights into the C budget of grassland ecosystems and increase our understanding of the role of C fixation and partitioning when plants respond to environmental challenges. [Display omitted] • Carbon (C) assimilation and allocation was evaluated by 13C tracing technique. • More 13C allocated to aboveground tissues for photosynthesis under light grazing. • Light grazing promoted C fixation and turnover of leaves and NSC storage of stems. • Under grazing pressure L. chinensis increased NSC storage across organs. • The production of SM increased in leaves as increasing herbivory pressure. [ABSTRACT FROM AUTHOR]

[Display omitted] • Water recession pattern were classified as optimal, early, or late water recession. • Phenological mismatch is the days between geese arrival and timing of optimal NDVI. • Unusually early or late water level recession leads to a greater mismatch. • Greater mismatch negatively affected Lesser White-fronted Goose abundance. • Greater mismatch resulted in a clumped Lesser White-fronted Goose distribution. Phenological mismatches between migratory birds and food availability driven by global warming have been found to influence the fitness and population dynamics of several herbivorous goose species in Arctic breeding sites. However, the effect of phenological mismatches at wintering sites have been inadequately studied. We used long-term data to explore the consequences of water regime changes on phenological mismatch (i.e., days between arrival of geese and timing of the optimal Normalized Difference Vegetation Index [NDVI opt ]) and detect the relative role of the mismatch as a driver of annual variations in abundance and distribution of the Lesser White-fronted Goose Anser erythropus (a vulnerable species on the IUCN Red List) in East Dongting Lake, which is the one of this species' largest wintering sites worldwide. The NDVI of the Carex meadow (i.e., the dominant vegetation in East Dongting Lake wetland and also the major food resource for the geese) was used as the phenology metric. Results showed that the water recession pattern greatly influenced food conditions when geese arrived at the site. Early water recession led to significantly higher NDVI, whereas late water recession led to significantly lower NDVI than did the optimal water recession. However, the suitable habitat area was significantly larger under the optimal water recession pattern. Both early and late water level recessions caused greater mismatches and resulted in lower geese abundance and a more concentrated distribution. NDVI was positively correlated with aboveground biomass and negatively correlated with N% of Carex spp. High biomass and low N% related to high NDVI caused by early water recession may indicate unfavorable food conditions at the time that geese arrive and reduced sustainable food availability in mid-winter, while a low NDVI and limited habitat area caused by late water recession may indicate an insufficient food supply. In conclusion, non-optimal water recession led to a greater phenological mismatch and resulted in limited habitat quality (e.g., lower leaf N%) under early water recession but limited habitat quantity (e.g., smaller habitat area and lower aboveground biomass) under late water recession, and ultimately threatened the Lesser White-fronted Goose. Our results contributed to explaining the decline of the Lesser White-fronted Goose population in this wintering site. [ABSTRACT FROM AUTHOR]

Panax notoginseng (Bruk.) FH Chen is a valuable traditional herb in China, with saponins being the main medicinal components in its roots. However, leaf diseases are a major factor limiting growth and production of P. notoginseng. Melatonin is a ubiquitous signaling molecule associated with abiotic stress resistance. In this study, we investigated the role of melatonin in leaf disease resistance of P. notoginseng in field conditions. Additionally, saponin concentrations were analyzed to evaluate the suitability of melatonin use in agricultural practice. Our results showed that exogenous application of melatonin promoted the endogenous phytomelatonin accumulation via upregulation of genes involved in its biosynthesis. The application of 10 μM melatonin decreased the incidence of leaf diseases (gray mold, round spot, and black spot) by about 40% compared with the solvent control, which might have been due to the increased expression of genes associated with immunity and disease resistance. Furthermore, concentrations of saponins and expression of their biosynthesis-related genes were significantly increased by melatonin. Taken together, the data presented here suggested that melatonin could be used in agricultural management of P. notoginseng because it increased leaf disease resistance and biosynthesis of saponins. [ABSTRACT FROM AUTHOR]