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In response to global climate change, China has committed to peaking carbon emissions by 2030 and achieving carbon neutrality by 2060, commonly known as the "30–60 Dual Carbon". Under the background of "30–60 Dual Carbon", this article takes the electric power industry, which is the main industry contributing to China's carbon emission, as the research object, explores the time and peak value of the carbon peak of the electric power industry, and analyzes whether carbon neutrality can be realized under the peak method, so as to get the carbon neutrality path of the electric power industry and serve as the theoretical basis for the formulation of relevant policies. The Environmental Kuznets Curve inspection and the relationship analysis are carried out, then the system dynamics model is constructed, the carbon emissions from 2020 to 2040 are simulated, and the peak time is predicted. Three different scenarios are set to explore the path of electricity carbon neutralization under the premise of a fixed peak. It is shown that Gross Domestic Product per capita index factors have the largest positive contribution, and thermal power share index factors have the largest negative contribution to electricity carbon emissions. Based on the current efforts of the new policy, carbon emissions can achieve the peak carbon emissions' target before 2030, and it is expected to peak in 2029, with a peak range of about 4.95 billion tons. After the power industry peaks in 2029, i.e., Scenario 3, from coal 44%, gas 9% (2029) to coal 15%, gas 7% (2060), where the CCUS technology is widely used, this scenario can achieve carbon neutrality in electricity by 2060. Adjusting the power supply structure, strictly controlling the proportion of thermal power, optimizing the industrial structure, and popularization of carbon capture, utilization, and storage technology will all contribute to the "dual carbon" target of the power sector. [ABSTRACT FROM AUTHOR]

Unconventional water resources (e.g., saline water, etc.) for irrigation as a promising supplementary water source can alleviate the freshwater shortage in the agriculture of red soil areas in Southern China. It should be noted that the presence of soluble salt in this water source may have detrimental influences on soil water infiltration and crop growth. Understanding the effect of unconventional water irrigation (UWI) on water infiltration in red soil is important. Previous studies have shown that the salinity of UWI can alter soil hydraulic properties to change soil water movement in saline soils. However, the underlying mechanism and factors of water infiltration in red soil under UWI with different salinity levels remain limited. Therefore, a laboratory experiment (one-dimensional vertical infiltration experiment and centrifuge method) was conducted to evaluate the effect of UWI with different salinity levels [0 (the distilled water, CK), 1 (S1), 2 (S2), 3 (S3), 5 (S5), and 10 (S10) g L−1] on the soil water infiltration process, soil water characteristic curve (SWCC), soil water constants estimated using the SWCC, saturated and unsaturated hydraulic conductivity (KS and K) as well as the soil chemistry of soil profile [pH, electrical conductivity (EC), and Na+ and Cl− contents]. The primary factors of soil water infiltration were identified using stepwise regression and path analysis methods. The results showed that UWI salinity decreased water infiltration by 1.53–7.99% at the end of infiltration in red soil, following the order of CK > S1 > S5 > S2 > S3 > S10. Moreover, UWI could enhance soil water availability with an increase of 8.55–12.68% in available water capacity. In contrast, lower KS and K were observed in S1–S10, and there was a negative linear relationship between irrigation salinity and KS. UWI also produced the EC, Na+, and Cl− accumulations in the soil profile. As the salinity level of UWI increased, the accumulations aggravated. Soil acidification was found in S1–S5, while soil alkalization was observed in S10. Additionally, α, PWP, and KS were the primary factors influencing the water infiltration of red soil. This study can help optimize the soil infiltration model under UWI and establish a foundation for unconventional water management in the red soil regions of Southern China and other similar regions. In addition, the undisturbed red soil under agricultural unconventional water irrigation and the long-term effect of unconventional water application should be considered. [ABSTRACT FROM AUTHOR]

Water scarcity poses a formidable challenge to agricultural productivity in arid regions, and water retention agents offer promising potential in this regard. Therefore, this study proposes developing and preparing polymers with water retention properties using waste green algae as raw material to explore the effectiveness of enhanced water infiltration and reduce evaporation at different use levels (0%, 0.15%, 0.30%, 0.45% and 0.60%) and maximum mixing depths (10 cm, 20 cm, 30 cm, 40 cm and 50 cm) and determine the optimum management. The results demonstrate that the synthesized polymers exhibited a remarkable swelling rate of 143.6 g/g, along with reusability and excellent temperature stability. The polymer application rate was positively correlated with infiltration duration, with an increase from 161 min to 750 min as the application rate rose from 0% to 0.60%. Concurrently, cumulative infiltration increased from 22.6 cm to 31.1 cm, showcasing the benefits of the polymer in enhancing water retention. Intriguingly, cumulative evapotranspiration initially decreased and then increased with increasing polymer application rates. Moreover, increasing the maximum mixing depth from 10 to 50 cm while maintaining the 0.3% application rate increased the cumulative infiltration (from 22.6 cm to 31.1 cm) and infiltration rate (from 0.03 cm/min to 0.08 cm/min) while decreasing the cumulative evaporation (from 44.4 mm to 31.7 mm). Considering the cumulative infiltration, infiltration rate and evapotranspiration characteristics, an optimized polymer application rate of 0.27% at a mixing depth of 0–50 cm was recommended for efficient soil moisture management. This study highlights the potential of green algae-derived biodegradable polymers as a win–win strategy for achieving waste alleviation of water scarcity in drylands, particularly for maize and wheat cultivation in northern China. [ABSTRACT FROM AUTHOR]

Rapeseed is one of China's major oil crops, and accurate yield forecasting is crucial to the growth of the rapeseed industry and the country's food security. In this study, the data on natural and socio-economic factors from 2001 to 2020 and the yield of rapeseed in China were used as the data basis. The Pearson correlation coefficient was used to analyze the relationship between the influencing factors and the yield of rapeseed, and the prediction effect of four machine learning models (linear regression (LR), decision tree (DTR), random forest (RF), and support vector machine (SVM)) on the yield of rapeseed was compared in China's main rapeseed-producing area. The results demonstrate that the yield of rapeseed in China showed an increasing trend, but fluctuated greatly. Rural electricity consumption, gross agricultural production, the net amount of agricultural fertilizer application, effective irrigation area, total power of agricultural machinery, and consumption of agricultural plastic film had a positive effect on the increase in rapeseed yield. However, due to the impact of climate change and disasters, the yield of rapeseed has had significant fluctuations. A Pearson correlation analysis showed that socio-economic factors (rural electricity consumption, gross agricultural production, effective irrigation area, total power of agricultural machinery, consumption of agricultural plastic film, etc.) played a dominant role in rapeseed yield changes. The RF model had a good prediction effect on rapeseed yield, and natural factors and socio-economic factors had different effects on spring rapeseed and winter rapeseed. Winter rapeseed yield was mainly affected by socio-economic factors, accounting for as high as 89% of the importance. Among them, the sown area of rapeseed and the effective irrigation area had the greatest impact. The effects of natural factors and socio-economic factors on spring rapeseed yield were similar, accounting for 47% and 53%, respectively, and the mean annual precipitation, sunshine duration, and sown area of rapeseed were the most influential variables. [ABSTRACT FROM AUTHOR]

The cultivation of Panax notoginseng has been plagued by a multitude of challenges, including recurrent diseases, suboptimal value, inadequate quality, and environmental degradation resulting from improper water and fertilizer management. To address these issues and improve the yield of P. notoginseng and its saponin content, this study endeavors to identify the optimal irrigation and fertilization levels in shaded environments in Yunnan Province in Southwest China. In this field experiment, three-year-old plants were tested to evaluate the effects of water, soluble organic fertilizers, and their combinations on plant growth, physiological parameters, yield, and saponin content. The experiment included 12 treatments with three types of irrigation (10 (W1), 15 (W2), and 20 (W3) mm), totaling 440, 660, and 880 mm, and four levels of the total amount of fertilization (F1 (60, total N 12.6, total P 5.5, and total K 10.5 kg ha−1), F2 (90, total N 18.9, total P 8.3, and total K 15.7 kg ha−1), F3 (120, total N 25.2, total P 11.0, and total K 20.9 kg ha−1), F4 (150, total N 31.5, total P 13.8, and total K 26.1 kg ha−1)). The randomized complete block design was used, with 36 plots in total and 3 replications. The study utilized the TOPSIS method to determine the most effective water and fertilizer management strategy for the growth and production of P. notoginseng. The assessment of yield, water and fertilizer productivity, and saponin content across all treatments revealed that the W3F3 treatment resulted in significant increases in the plant's height, stem diameter, and net photosynthetic rate. Meanwhile, the W2F3 treatment exhibited the best root morphological traits. The W3F4 treatment effectively increased dry matter and transpiration. The combination of water and fertilization had a coupling effect that not only increased yield to 1400 kg ha−1 but also improved water–fertilizer productivity. The application of the W2F3 treatment resulted in a significant increase in the accumulation of active components, leading to a total P. notoginseng saponin (PNS) content of 24.94%. Moreover, the comprehensive index obtained through the TOPSIS model indicated that the W2F3 treatment outperformed other treatments. Therefore, this treatment can be considered a promising water and fertilizer model for P. notoginseng cultivation, which can enhance its yield, quality, and productivity while promoting sustainable green development. [ABSTRACT FROM AUTHOR]

Panax notoginseng is an important medicinal crop in China. The high incidence of root rot in P. notoginseng during the rainy season has restricted the development of the industry. It is believed that frequent rainfall and a warm soil environment are important factors that promote root rot incidence. However, there is still a significant knowledge gap in the relationship between rainfall and root rot incidence. To understand the effects of rainfall and fertilizer on root exudates, the soil bacterial structure, and root rot in P. notoginseng, four treatments were chosen for both field and pot experiments. These treatments included DW (rain shelter and no fertilizer), RW (no rain shelter and no fertilizer), DWF (rain shelter and fertilizer), and RWF (no rain shelter and fertilizer). The results showed that both factors (rain shelter and fertilizer) significantly affected root rot incidence and several other parameters. Among them, the effect of a rain shelter is more significant than that of fertilizer, and the combination of the two further improves the effect. DW and DWF treatments significantly reduced the soil moisture, phenolic acid, and root rot incidence, while significantly increasing the soil temperature and enzyme activities compared to RW or RWF. Seven phenolic acids secreted by P. notoginseng roots were all positively correlated with root rot incidence. Root rot was also positively correlated with Planctomycetota, Acidobacteriota, and Gemmatimonadota and negatively correlated with Firmicutes, Proteobacteria, Patescibacteria, and Nitrospirota. DWF treatment decreased the soil moisture and the concentration of p-hydroxybenzoic acid, syringic acid, phthalic acid, and vanillic acid and promoted the growth of Firmicutes and Proteobacteria, leading to the lowest incidence of root rot. [ABSTRACT FROM AUTHOR]

Affected by global warming, the frequency of crop pests and diseases have increased, causing huge losses to agricultural production. To better grasp the development and trends of research on the effects of climate change on crop pests and diseases, the literature on the impact of climate change on crop pests and diseases published from 1990 to 2021 in the Web of Science (WOS) core collection database was used. This study explores the literature characteristics and hotspot evolution through the bibliometric visualization analysis software COOC, VOSviewer, and CiteSpace, with a view to identifying the changing characteristics and trends of research changes in this field. The results showed that the number of literature on the impact of climate change on crop pests and diseases increased rapidly. The main fields involved include environmental sciences, ecology, and agronomy. Papers in these fields mainly published in journals, such as PLos One, Forest Ecology and Management, and Frontiers in Plant Science. The country with the highest number of publications was the United States, followed by China and Australia. The most prolific authors in the top 20 are research scholars from China. The first author of the top 20 highly cited papers was from the United States. It was found that that current research on the impact of climate change on crop pests and diseases mainly focuses on agricultural production and food safety. Modelling and crop growth has maintained steady development. At present, research in this field mainly focuses on pest management strategies under the impact of climate change, the response of single species, and the complex ecological mechanisms behind the response. This study provides unique insights into the research field of the impact of climate change on crop pests and diseases and provides a reference direction for future research development in this field. [ABSTRACT FROM AUTHOR]

Reasonable water and light management technology can improve economic benefits, coffee yield, and quality. We used cluster analysis and principal component analysis to evaluate and optimize the water and light management technology with high coffee yield, quality, and economic benefits in a subtropical monsoon climate region of China. The experiment was arranged in a randomized complete block design with two factors (3 irrigation levels × 4 shade cultivation treatments) replicated four times during 2016–2017. The irrigation levels consisted of full irrigation (FI) and two deficit irrigations (DI L : 75% FI, DI S : 50% FI). The shade cultivation treatments consisted of no shade cultivation (S0) and three shade cultivation modes (S L : intercropping with four lines of coffee and one line of banana; S M : intercropping with three lines of coffee and one line of banana; S S : intercropping with two lines of coffee and one line of banana). The results showed that the effects of irrigation level and shade cultivation mode on growth, crop yield, most of the photosynthetic characteristics, and nutritional quality were significant (p < 0.05). Regression analysis showed that the leaf radiation use efficiency (RUE) showed a significant negative exponential relation or logistic-curve variation with photosynthetically active radiation (PAR). The bean yield increased with an increase of the shade degree when water was seriously deficient, whereas it first increased and then decreased with an increase of the shade degree under FI and DI L . Based on both cluster analysis and principal component analysis, the FIS S treatment resulted in the highest comprehensive quality of coffee, followed by the FIS M treatment; the DI S S0 treatment obtained the lowest quality. Compared with the FIS0 treatment, the FIS M treatment increased the 2-year average bean yield and net income by 15.0 and 28.5%, respectively, whereas the FIS S treatment decreased these by 17.8 and 8.7%, respectively. To summarize, FIS S treatment significantly improved the nutritional quality of coffee, and FIS M treatment significantly increased the dry bean yield and economic benefits of coffee. The results of the study could provide a theoretical basis for water-saving irrigation and shade cultivation management of coffee in a subtropical monsoon climate region of China. [ABSTRACT FROM AUTHOR]

Evaporation is important basic information for irrigation decision making in water resources management. Developing countries usually use a small pan to observe surface evaporation, but the relationship between evaporation in different small pans is not sufficiently clear. In this paper, we use an extreme learning machine (ELM) model to predict and convert E20 (diameter 0.20 m) and E601 (diameter 0.62 m) pan data for 38 meteorological stations in southern China. Firstly, we obtained the best combination of meteorological parameters for forecasting E20 and E601, respectively, and we also found that the accuracy of the model can be significantly improved by adding pan data. Secondly, we found that during the conversion between E20 and E601, the model performance when using E601 data to predict the E20 evaporation is better than that when using E20 data to predict the E601 evaporation. Finally, the geographical factors were analysed, and the model performance was found to be relatively poor in the coastal area and the North–South junction. [ABSTRACT FROM AUTHOR]

Currently, building energy consumption accounts for a considerable proportion of the world's energy consumption, e.g., 35 % in China, which has become a key concern with its rising proportion. Accurate prediction of building hourly energy consumption is key to realizing green, low-carbon, and energy-saving modern buildings. However, most of the current prediction methods are only based on dynamic data from IoT (Internet of Things) systems that may contain a large number of outliers, resulting in lower accuracy and reliability. To solve this problem, with the help of rich data provided by BIM (Building Information Modelling), we propose an approach named dynamic and static hybrid data analysis (D&S-HDA) that can provide a solution with better prediction accuracy. Technically, the novelties of D&S-HDA are fourfold. Firstly, we establish the D&S-HDA framework to obtain more accurate prediction outcomes, where the electricity consumption prediction results based on dynamic data analysis are weighted with the estimation values based on static data analysis. Secondly, in the dimension of dynamic data analysis, we design an improved temporal convolutional networks (TCNs) for parallelly outputting dynamic data samples to make the prediction results more intuitive. Thirdly, in the dimension of static data analysis, a novel concept of building hourly power consumption coefficient(BHPCC) is proposed, and its calculation method using static data analysis is designed to estimate hourly electricity consumption. Finally, in order to validate the effectiveness of our D&S-HDA approach, we design multidimensional evaluation metrics and conduct multi-group comparative experiments under different conditions, including climate models, electricity usage behaviour and time scales. The experimental results reveal that the proposed D&S-HDA approach outperforms current mainstream works in terms of root mean square error (RMSE), mean absolute error (MAE) and mean absolute percentage error (MAPE), with values of 1.5248, 1.0693 and 2.9505, respectively, which shows the efficiency and feasibility of the proposed D&S-HDA. [ABSTRACT FROM AUTHOR]

This paper analyzed the drought situation in southwestern China with the standardized precipitation index (SPI) and the standardized precipitation–evapotranspiration index (SPEI) on multiple time scales. The spatial distribution, seasonal variation and features of drought in southwestern China were examined separately by drought frequency, probability of non-exceedance and runs theory. The results showed that the precipitation sequence will change suddenly near 2073 and an obvious, long-term drought will occur after 2073 due to the decline in precipitation. The spatial distribution of drought frequency indicated that the drought frequency will grow obviously in 2071–2100, and the growth rate will increase from the peripheral to the center of the region. The probability of non-exceedance for SPEI-1 less than − 1.0 will be 14.6% in the spring of 2011–2040, grow in 2041–2070 and reach 25.9% in 2071–2100, while that of SPEI in winter will gradually increase in all periods. When the SPEI-12 is smaller than − 1.0, the non-exceedance probability of the index in all seasons of 1981–2100 was and will be growing gradually, indicating that climate change has and will cause severe droughts in spring and winter from 1981 through 2100, especially the medium- and long-term drought. Through the analysis of the SPI and SPEI time sequences by runs theory, it is observed that the drought severity predicted by SPI-12 was and will be increasing over time, and the long-term drought will become more serious. On all time scales, if the SPEI is smaller than − 1.0, the drought duration will gradually increase from 1981–2010 to 2071–2100, indicating the drought in the study region will worsen due to climate change. [ABSTRACT FROM AUTHOR]

Equine hepacivirus (EqHV), equine pegivirus (EPgV) and Theiler’s disease-associated virus (TDAV) are three novel equine viruses in the family Flaviviridae. EqHV and EPgV have been identified to circulate in the equine population worldwide, whereas TDAV has not been detected in equines since the first reported case. To date, no studies have focused on investigating EqHV, EPgV and TDAV in commercial equine sera or equine blood products in China. Considering the potential threat of EqHV, EPgV and TDAV to biosecurity and considering their possible influences on research results, equine sera for cell culture propagation and pregnant mare serum gonadotropin (PMSG) were purchased from different companies in China and investigated for EqHV, EPgV and TDAV in this study. By performing nested PCR or two rounds of PCR targeting the viral NS3 gene, four serum samples were confirmed to be EqHV-, EPgV-, or TDAV-RNA positive; all of the PMSG samples were negative for these three viruses. Subsequent sequencing results indicated that the serum samples contained multiple viral variants of EqHV, EPgV or TDAV, and a genetic analysis based on the partial NS3 gene of the three equine viruses was performed. Our study is the first to confirm the presence of EqHV, EPgV and TDAV in equine sera for cell culture propagation that is commercially available in China and provides the first demonstration of the presence of TDAV in China. [ABSTRACT FROM AUTHOR]

The yield of Panax notoginseng (BurK.) F. H. Chen in Yunnan Province accounted for more than 90% of China's total yield, but extensive water and fertilizer management restricted improvement of yield, quality, and economic benefits of Panax notoginseng. Therefore, this study tried to propose an adaptive irrigation and fertilizer management strategy for Panax notoginseng production. A two-year (2017 and 2018) rain-shelter cultivation study in Yunnan Province of southwest China was conducted to analyze the influences of irrigation and organic fertilizer application on soil water distribution, root growth, water-fertilizer productivity, quality, and economic benefits of Panax notoginseng in four organic fertilizer application rates [500 (F 1), 1000 (F 2), 1500 (F 3), and 2000 (F 4) kg ha−1] combined with three micro-sprinkler irrigation schedules [I 1 : moderate deficit micro-sprinkler irrigation, (70–75%) θ FC ; I 2 : alternate micro-sprinkler irrigation, (70–75%) θ FC / (80–85%) θ FC ; I 3 : slight deficit micro-sprinkler irrigation, (80–85%) θ FC ]. The results indicated that the increasing micro-sprinkler irrigation levels enhanced soil water content in 0–40 cm soil layer, but resulted in a reduction irrigation water productivity (IWP). Moreover, the increasing organic fertilizer application significantly led to reduced partial fertilizer productivity (PFP). Under the interaction of micro-sprinkler irrigation schedules and organic fertilizer application in 2017 and 2018, the I 2 F 3 significantly obtained the highest soil water storage (SWS), root hydraulic conductivity, root morphological characteristics, root-shoot ratio, lowest root rot rate (4.68% in 2017 and 6.59% in 2018), largest yield (3614.5 kg ha−1 in 2017 and 3981.5 kg ha−1 in 2018), total saponin content (20.23% in 2017 and 23.28% in 2018), and economic benefits (25.28 × 104 $ ha−1 in 2017 and 32.6 × 104 $ ha−1 in 2018) of Panax notoginseng. Based on the above results, the comprehensive evaluation of five saponin contents and the comprehensive evaluation of the yield, IWP, PFP, economic benefits, and total saponin content of Panax notoginseng were analyzed by using a TOPSIS model in 2017 and 2018. We found that synergistic of alternate micro-sprinkler irrigation [I 2 , (70–75%) θ FC / (80–85%) θ FC ] and organic fertilizer application (F 3 , 1500 kg ha−1) could decrease root rot, improve root growth, water-fertilizer productivity, quality, and economic benefits of Panax notoginseng. [Display omitted] • Alternate irrigation synergized with organic fertilizer (AIOF) was a sustainable technology of Panax notoginseng production. • The AIOF promoted root growth and decreased root rot incidence of Panax notoginseng. • The AIOF improved water-fertilizer productivity, quality, and economic benefits of Panax notoginseng. [ABSTRACT FROM AUTHOR]

Panax notoginseng (Burk) F. H. Chen, called Sanqi, is a valuable herbal plant and is widely used in Chinese medicine. However, the yield and saponin content cannot be guaranteed due to irrational irrigation and fertilizer management in low-latitude regions in southwestern China. To obtain suitable irrigation and organic fertilizer modes for improving the yield and saponin content of the plant, a shelter experiment was conducted using a randomized complete block design with a factorial arrangement of treatments with three replications. Three irrigation regimes, D L , D M and D S (irrigation upper/lower limit: 65–50% θ f , 50–35% θ f , and 35–20% θ f , respectively, where θ f is the field capacity), three organic fertilizer levels, F L , F M and F H (33, 48 and 63 t ha−1, respectively), and a control group, CK (65–50% θ f and 3 t ha−1), were applied in the two-year and eight-month growth cycles. With the paired comparison design, the results indicated that the flower dry yield, root dry yield and Panax notoginseng saponins (PNS) were significantly affected by different water deficit irrigation and organic fertilizer treatments, and they first increased and then decreased with increased water deficit or organic fertilizer. Compared with D L F H , D M F M reduced water use by 42.39% and fertilizer use by 23.81%, and the flower dry yield, root dry yield, PNS , water use efficiency and partial factor productivity of fertilizer increased by 19.67%, 22.52%, 54.33%, 149.72% and 91.83%, respectively. Under the D M F M treatment, the dry root yield and saponin content for 3-year-old P. notoginseng were 3039.19 kg ha−1 and 10.85%, respectively, which were higher than those resulting from other treatments. Additionally, the PNS resulting from D M F M exhibited the highest comprehensive score and comprehensive index based on principal component analysis and the TOPSIS model. This combination could create a higher yield of flowers and roots, provide a scientific management for planting, and improve the economic benefits for planters and the local government. • Study highlights role of deficit irrigation and organic fertilizer on Panax notoginseng growth. • Fertigation with highest irrigation and fertilizer amount increase root disease incidence and decrease root dry yield. • Severe drought stress significantly increased the water use efficiency for P. notoginseng. • Organic fertilizer schedule with water irrigation amount of 50~35% θf is proposed. [ABSTRACT FROM AUTHOR]

Cotton is the most widely planted fiber crop in the world and plays an important role in the national economy. Climate change alters the environmental elements of crop growth such as sunlight, moisture, and soil through changes in temperature and precipitation, which in turn affects the phenology period, growth potential, and cropping system of cotton, and ultimately affects yields. Studying the feedback of cotton growth to climate change is of great practical significance for cotton planting planning and yield increase and stabilization. Crop growth is affected by both climate and management measures, but most studies often ignore the impact of management measures, resulting in the inability to accurately assess the impact of climate. And existing research is mostly based on single sites or some provinces, lacking regional research on the main cotton producing areas in China. This study calibrated the AquaCrop model using data from 40 sites from three major cotton growing regions in China collected over different time periods between 1978 and 2018 and simulated the climate change impact on cotton for the subsequent years. The model showed good applicability in simulating the growth process of cotton in the study areas. The above-ground biomass (Bio), potential yield (Py) and water use efficiency (WUE) of cotton under the influence of climate change showed an increasing trend of 98% (39/40), 98%, and 93% of the sites, while the actual evapotranspiration (ET a) mainly decreased. Elevated CO 2 concentration increased cotton yield. The main climatic variables affecting cotton growth were wind speed, solar radiation, sunshine hours, and minimum and maximum temperature. Climate variables explained the changes in ET a , Bio , Py , and WUE by 65.1–95.5%, 9.7–74.5%, 14.8–68.3%, and 15.2–90.4%, respectively. Overall, cotton growth showed close relation to changes in W s , R s , T min , and T max. The study quantitatively analyzed and identified the main climatic factors affecting cotton growth and found that climate change and elevated CO 2 concentrations have a positive impact on cotton production. The simulations conducted in this study using multi-site data provided reliable regional information that can help develop future management strategies to maintain current and meet future demand for cotton in China, and provide recommendations and guidance for environmental regulation and sustainable discovery of the cotton growing process. [Display omitted] • The applicability of the AquaCrop model in the three major cotton producing regions in China was evaluated. • The effects of climate change on cotton growth and yield in china were analyzed under with unchanged management measures. • Cotton growth and yield changes under constant and elevated CO 2 concentration scenarios were comparatively analyzed. [ABSTRACT FROM AUTHOR]

• Water, N and year significantly affect dry matter accumulation, fruit yield, quality, water and N productivity. • The Entropy Weight-TOPSIS method was adopted to achieve the multi-objective optimization of water and N fertilizer. • I80N360 (80% ET 0 - 360 kg N ha−1) is the ideal water and N management strategy for greenhouse cherry tomato. In the context of climate-change and shortage of fresh water resources, improving agricultural productivity has become a major challenge globally, especially in China with large population. In this study, the purpose was to achieve the optimal combination of water and nitrogen (N) rates for greenhouse cherry tomato based on fruit yield, quality, net income and water-N productivity. Herein, during 2019–2021, three irrigation levels (I100: 100% ET 0 ; I80: 80% ET 0 ; I60: 60% ET 0 , where ET 0 was the reference evapotranspiration) and five N rates (450, 360, 270, 180 and 0 kg N ha−1, defined by N450, N360, N270, N180 and N0, respectively) with 15 treatments were set up. The 3-year ANOVA analysis indicated that irrigation, N fertilizer and year had significant effects on dry matter accumulation, fruit yield, quality, water and N productivity of greenhouse cherry tomato. Both the highest fruit yield (56.72 t ha−1, average of 3-year) and net income (60.8 × 104 CNY ha−1) were occurred under I80N360 treatment, though peak N partial factor productivity (PFPN, 294.88 kg−1) was observed under I80N180 treatment. The combined application of water and N fertilizer increased water productivity (WP) by 15.64% (average of 3-year) compared to I60N0 treatment, with I80N360 and I60N270 treatments having the highest WP. N fertilizer addition significantly increased fruit yield and WP irrespective of irrigation level, but the differences between N360 and N450 treatments were not significant in 80% ET 0 and 100% ET 0 irrigation level treatments, and between N270, N360 and N450 treatments in 60% ET 0 irrigation level treatments. Nevertheless, PFPN decreased significantly as the N rate increased. In addition, fruit quality could be improved at some extent under deficit irrigation relative to full irrigation regardless of N rate. More specifically, compared with the full irrigation treatment (I100), the I80 treatment increased the content of total soluble solid (TSS) by an average of 6.68%, soluble sugar (SS) by 11.96%, organic acid (OA) by 4.91%, sugar acid ratio (SAR) by 11.28%, vitamin C (VC) by 14.55%, lycopene by 30.06% and firmness by 7.60%; meanwhile, the I60 treatment increased TSS by an average of 11.17%, SS by 18.60%, OA by 12.04%, SAR by 10.02%, VC by 27.55%, lycopene by -7.93% and firmness by 13.14%, respectively. The increase of N rate largely increased TSS, SS, SAR, VC and lycopene, while these indicators decreased when N rate exceeded a threshold. Nevertheless, OA and firmness increased with increasing N rate, while firmness showed a slight decrease when N rate increased from N360 to N450 treatment. Generally, in a greenhouse cherry tomato production agroecosystem, the optimal amount of N fertilizer applied for each indicator varies with the availability of irrigation water. Furthermore, the Entropy-Weight TOPSIS method was adopted and the results indicated that the optimization of irrigation and N fertilizer supply schedule (I80N360 treatment: 80% ET 0 –360 kg N ha−1) was conducive to increase fruit yield, net income and water-N productivity whilst maintaining fruit quality in greenhouse cherry tomato cultivation. [ABSTRACT FROM AUTHOR]

The knowledge of seasonal nutrient demand is necessary for maximizing potato yield and resources use efficiency under drip fertigation, and it also can effectively mitigate the risk of nutrient leaching caused by excessive fertilization. To explore the coupling effects of irrigation level and fertilization rate on drip-fertigated potato growth, nutrient accumulation and determine the multi-objective optimal irrigation and fertilization regimes, a two-year (2018 and 2019) field experiment was conducted in the sandy regions of northern China. The experiments included three irrigation levels (I 60 , 60% ET C ; I 80 , 80% ET C and I 100 , 100% ET C , where ETc is the crop evapotranspiration) and five fertilization rates (N 0 P 0 K 0 , 0 kg ha−1; N 1 P 1 K 1 , 100–17.5–124.5 kg ha−1; N 2 P 2 K 2 , 150–26.2–186.7 kg ha−1; N 3 P 3 K 3 , 200–34.9–248.9 kg ha−1 and N 4 P 4 K 4 , 250–43.7–311.2 kg ha−1, where the ratio of N, P and K was 1:0.17:1.24). The results showed that N, P and K accumulated rapidly from 42th to 95th, 50th to 96th and 46th to 91th days after sowing, respectively. For producing 1000 kg tuber yield, the required amounts of N, P and K were 1.97–4.16 kg, 0.55–0.81 kg and 4.83–7.65 kg, respectively. The uptakes of N, P and K in 1000 kg tubers across all treatments were 1:0.18–0.34:1.61–2.59, with the average N:P:K ratio of 1:0.23:2.05. Besides, irrigation level, fertilization rate and their interaction had significant effects on potato leaf area index, biomass, N, P and K accumulation. Deficit irrigation reduced seasonal LAI, biomass, N, P and K accumulation, tuber yield and apparent fertilizer recovery (AFR), but increased water productivity. High fertilization rate was conducive to promoting nutrient absorption, plant growth and improving tuber yield, while it reduced the unit nutrient productivity. The AFR increased first and then decreased with the increase of fertilization rate. To simultaneously achieve high potato yield and resources use efficiency, a multi-objective optimization model was established using the binary quadratic regression analysis between tuber yield, net income, water productivity, AFR and water–fertilizer regimes, which showed that tuber yield, net income, water productivity, and AFR could obtained ≥ 90% of their maximum values simultaneously when the irrigation interval was 204–262 mm and fertilization (N-P-K) interval ranged from 200–24–248 to 247–42–306 kg ha−1. The findings can provide useful information for optimizing irrigation and fertilization regimes in sandy regions of northern China. ● Nutrient uptake process under virous drip fertigation combinations was explored. ● Water and fertilization had significant effects on nutrient accumulation and yield. ● 1.97–4.16 kg N, 0.55–0.81 kg P and 4.83–7.65 kg K were needed to produce 1 t tuber. ● Interval of fertigation was put forward through a multi-objective optimization model. [ABSTRACT FROM AUTHOR]

The yield and quality of Arabica coffee ( Coffea arabica ) cannot be guaranteed due to irrational irrigation and light management in dry and hot regions of southwest China. The objective of this study was to obtain rational irrigation and shading mode for efficient light and water use, suitable yield and high nutritional quality of Arabica coffee. Taking full irrigation (FI) as the control, the effects of deficit irrigation (DI) (DI75 and DI50, 75 and 50% of full irrigation amount, respectively) on photosynthesis, yield, nutritional quality and water use efficiency (WUE) were investigated under four shading levels (Sh0 no shading, Sh30, Sh45 and Sh60, 30, 45 and 60% shading, respectively) using the field experiments, and a comprehensive benefit assessment model of yield, nutritional quality and WUE was established under different irrigation and shading treatments. Results indicated that DI75 increased leaf apparent radiation use efficiency and the contents of crude fat and chlorogenic acid in dry bean if compared to FI. In comparison with Sh0, Sh30 enhanced dry bean yield, WUE and the contents of total sugar and chlorogenic acid in dry bean. Compared with FISh0 (CK), DI75Sh30 raised dry bean yield, WUE, and the contents of total sugar, protein, crude fat and chlorogenic acid, but reduced the caffeine content. Principal component analysis showed that DI75Sh30 had optimal comprehensive nutritional quality, and TOPSIS method indicated that DI75Sh30 had the optimal comprehensive benefit, showing that our results can provide scientific basis for rational irrigation and light management of Arabica coffee in dry and hot regions. [ABSTRACT FROM AUTHOR]

Water and fertilizer are two important factors affecting crop growth and yield. Crop growth models are powerful tools for making irrigation and fertilization scheduling and predicting crop yield. The performance of crop models on potato under different irrigation amounts along with different N, P and K rates has been rarely evaluated, especially under drip fertigation. In this study, the accuracy of AquaCrop and DSSAT-SUBSTOR-Potato models in simulating potato growth, yield and water productivity under different drip fertigation regimes was compared. For model calibration and validation, a two-year field experiment with three irrigation levels (W 1 , 60% ET C ; W 2 , 80% ET C and W 3 , 100% ET C , where ET C was the crop evapotranspiration) and four fertigation (N-P 2 O 5 -K 2 O) rates (F 1 : 100–40–150 kg ha−1, F 2 : 150–60–225 kg ha−1, F 3 : 200–80–300 kg ha−1 and F 4 : 250–100–375 kg ha−1) was carried out in a sandy region of northwest China in 2018 and 2019. The statistical indicators showed that the AquaCrop model gave satisfactory predictions of canopy cover (R 2 ≥ 0.92, NRMSE ≤ 14.7%, d ≥ 0.96 and RMSE ≤ 10.8%), total dry matter (R 2 ≥ 0.92, NRMSE ≤ 25.0%, d ≥ 0.94 and RMSE ≤ 2.2 t ha−1), final dry tuber yield (R 2 ≥ 0.57, NRMSE ≤ 12.21%, d ≥ 0.82 and RMSE ≤ 0.83 t ha−1) and fresh tuber yield (R 2 ≥ 0.53, NRMSE ≤ 12.02%, d ≥ 0.81 and RMSE ≤ 4.91 t ha−1) in the four fertigation treatments (F 1 -F 4) under W 3 and W 2 during the two potato growing seasons. The final total dry matter and tuber yield under W 1 were over-estimated. The simulated water productivity and soil water content also agreed well with the observations (R 2 ≥ 0.91 , NRMSE ≤ 5.51%, d ≥ 0.94 and RMSE ≤ 0.48 kg m−3, and R 2 ≥ 0.40 , NRMSE ≤ 14.8%, d ≥ 0.77 and RMSE ≤ 11.5 mm). The simulation accuracy of DSSAT-SUBSTOR-Potato model was lower than that of AquaCrop model, which only showed a goodness of fit between simulated total dry matter, soil water content, tuber yield, water productivity and observations under high irrigation amount with high fertilization rate (W 3 F 4). Since the observed tuber yield increased with the increase of irrigation level (60–100% ET C) under the same fertigation rate, 120%ET C and 40%ET C were further simulated using the AquaCrop model to test the changes in tuber yield with further increased or decreased irrigation levels. The scenarios simulation showed that the tuber yield was only increased by 0.19%−1.52% under 120%ET C compared with that under 100% ET C , but 18.0% more irrigation water was consumed. Comprehensively considering water resources and tuber yield, the irrigation level of 100% ET C (W 3) along with fertigation (N-P 2 O 5 -K 2 O) rate of 200–80–300 kg ha−1 (F 3) was recommended for the sustainable potato production in the study region. The results of this study can provide guidance for the application of crop models in drip-fertigated potato. • AquaCrop and DSSAT-SUBSTOR-Potato were evaluated under various drip fertigation regimes. • AquaCrop adequately simulated the effects of irrigation and fertilization regimes on potato. • Simulation accuracy of DSSAT-SUBSTOR-potato was lower than that of AquaCrop. • 100% ET C along with N-P 2 O 5 -K 2 O rate of 200–80–300 kg ha−1 was recommenced for potato production. [ABSTRACT FROM AUTHOR]

Mango (Mangifera indica L.) is one of the widely grown fruit crops and brings remarkable economic benefit in the xerothermic regions of southwest China. However, mango yield and quality can not be guaranteed due to the severe seasonal drought, low precipitation and extensive management of water and fertilizer. To investigate the effects of irrigation amount and fertilizer regime on mango yield, fruit quality, water use efficiency (WUE) and partial fertilizer productivity (PFP), an orthogonal experiment [L 9 (3)4] was conducted on mango under drip fertigation during 2018–2019. The four factors were irrigation amount (IA) and fertilization rate at the flowering (F Ⅰ), fruit expansion (F Ⅱ) and fruit ripening (F Ⅲ) growth stages. There were three irrigation amounts, i.e., full irrigation (FI: 100%ET c), mild deficit irrigation (DI M : 75%ET c) and severe deficit irrigation (DI S : 50%ET c), and three fertilization rates, i.e., 75 (F 75), 50 (F 50) and 25 (F 25) kg ha−1 using a compound water-soluble fertilizer (N:P 2 O 5 :K 2 O=20%:20%:20%). The results showed the order of factors influencing fruit yield and WUE in terms of their importance was IA, F Ⅱ , F Ⅰ and F Ⅲ , that influencing water, vitamin C and carotenoid contents in fruit was IA, F Ⅲ , F Ⅱ and F Ⅰ , and that influencing soluble solids and total sugar contents was IA, F Ⅲ , F Ⅰ and F Ⅱ. The WUE of DI M F Ⅰ50 F Ⅱ75 F Ⅲ25 was highest. FIF Ⅰ25 F Ⅱ75 F Ⅲ50 achieved the highest fruit yield, PFP and contents of soluble solid, vitamin C and carotenoid. DI M F Ⅰ25 F Ⅱ50 F Ⅲ75 had the highest total sugar content and the lowest titratable acid content. Based on the comprehensive scoring method, DI M F Ⅰ50 F Ⅱ75 F Ⅲ25 achieved the optimum score in terms of fruit yield and water–fertilizer use efficiency, while FIF Ⅰ25 F Ⅱ75 F Ⅲ50 was optimum for fruit quality. Further, the TOPSIS method indicated DI M F Ⅰ50 F Ⅱ75 F Ⅲ25 had the optimal comprehensive benefit. To obtain high yield, quality and water–fertilizer use efficiency, the recommended water and fertilizer scheduling was irrigation with 75% ET c and fertilization with 50, 75 and 25 kg ha−1 at the flowering, fruit expansion and fruit ripening stages, respectively. The research results provided a scientific reference for identified optimum combination irrigation and fertilizer in the xerothermic environment of southwest China. • Fruit yield, WUE, PFP and quality were more sensitive to irrigation than staged fertilization. • Increasing fertilizer allocation at fruit expansion stage, FI elevated fruit yield and PFP, while DI M increased WUE. • Improving fertilizer allocation at the later growth, FI increased SS, VC and CC, while DI M increased TS. • Optimal strategy of irrigation and split fertilization for mango was revealed. [ABSTRACT FROM AUTHOR]

• Entropy weight method was used to determine the best water saving method for mango. • Sugarcane leaf mulching was significantly increased fruit yield and IWUE. • Sugarcane leaf mulching decreased the titratable acid by 31.3%. • Sugarcane leaf mulching with 50% ETC had the best fresh fruit quality. Rational application of field-management technology can not only improve mango (Mangifera indica L.) fresh fruit yield and quality but also improve irrigation water use efficiency (IWUE). However, few studies have involved the simultaneous use of mulch and irrigation-management techniques in hot and dry environments to achieve a relatively good level of performance. We used the entropy weight method (EWM) to explore an optimal mulching and irrigation-management technology for mango production in a dry hot environment. Three irrigation levels [FI, 100% mango evapotranspiration (ET C); DI 75 , 75% ET C ; DI 50 , 50% ET C ] were designed with (SM) and without (NM) sugarcane leaf mulching in 2018 and 2019 in a dry hot environment. The results showed that the photosynthetic rate, stomatal conductance, transpiration rate, leaf water-use efficiency, and carboxylation efficiency in the SM treatment were 12.5% to 83.7% higher than those in the NM treatment in both years. Compared with the NM treatment, the SM treatment increased the fresh fruit yield and IWUE by 45.7% and 49.7% in 2018 and by 46.1% and 63.2% in 2019. The solid-to-acid ratio and sugar-to-acid ratio in the SM treatment were 48.5% and 50.4% higher than those in the NM treatment, respectively, but the titratable acid content decreased by 31.3%. Compared with FI, DI 75 increased carotenoid content, total soluble solids, solid-to-acid ratio and sugar-to-acid ratio by 8.4%–40.7%, while it reduced titratable acid by 22.8%. Compared with FI, DI 50 reduced fresh fruit yield by 24.3% and 21.9% in 2018 and 2019, respectively, while it increased IWUE by 13.6% and 17.7%. The fresh fruit yield of SMDI 75 was the highest, which was 1.42 and 1.44 times that of NMFI in both years, respectively. A comprehensive evaluation by EWM also showed that the SMDI 50 treatment had the highest comprehensive scores of mango yield, quality and water-use efficiency, which could provide a basis for the scientific management of mango fertiliser in dry and hot areas of China. [ABSTRACT FROM AUTHOR]

Urban wetland ecosystems are easily influenced by heavy metals (HMs) because of their functional properties. In this study, absolute principal component scores-multivariate linear regression (APCS-MLR) and positive matrix factorization (PMF) receptor models were applied for the source apportionment of available occurrence forms of heavy metals (AHMs) of surface sediments in a typical urban wetland of Dianchi Lake, southwest of China. The risk assessment was conducted to evaluate the potential ecological/human health risks of HMs. Results indicated that Zn, Pb, and Cr were the major pollutants affected by anthropogenic activities in sediments and their concentrations were significantly exceeding the background value. Most of the highly AHMs-polluted area was close to the river in wetland, and the concentration distribution of all AHMs were generally low in the southwest and high in the northeast. Both APCS-MLR and PMF models identified three comparable classes of potential sources, namely (1) agricultural fertilizer/insecticide, atmospheric deposition, and traffic emissions; (2) natural transitions; and (3) industrial and sewage wastes. Moreover, the comparison results implied that the PMF model was more feasible for quantifying AHMs sources in wetland sediments since it is capable to analyze one more source, namely plant maintenance and waterfowl feeding, and has higher accuracy in predicting the concentrations of AHMs. In addition, the risk assessment model revealed that all these HMs were within the acceptable ranges of ecological and carcinogenic/non-carcinogenic human health risks. Among these, ingestion was the major exposure pathway of HMs from local areas, followed by dermal exposure and oral or nasal inhalation. However, children were more easily exposed to HMs than adults by ingestion due to their hand-to-mouth behaviors. This study aims to assess the HM pollution status in a plateau urban wetland, and provides a practical case for modeling source apportionment and risk assessment of HMs in wetland sediments., 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.)