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Water resources management and planning traditionally focus on visible liquid or blue water. However, green water also maintains social development and ecosystem services. Therefore, blue and green water should be incorporated into the watershed management system for evaluating water resources. To analyze the water resources of the Hanjiang River Basin, the SWAT model was set up using long-term and high-precision geographic data. The methods of wavelet analysis and Pearson's correlation analysis were used to explore the influence mechanism of climate and vegetation changes on the blue and green water flow (BWF and GWF) of the main ecosystems in the basin. The results showed that: (1) The spatial–temporal distribution of the BWF and GWF in the main ecosystems of the basin over the past 50 years was uneven. Forest ecosystems and farmland ecosystems have a greater concentration of water resources in the south, while grassland ecosystems have a greater concentration of water resources in the east. (2) Climate dominates the BWF and GWF changes in the main ecosystems of the basin. The BWF and the precipitation change cycle are synergistic, and the GWF and the temperature change cycle are synergistic. (3) The correlation between vegetation and BWF and GWF in the farmland ecosystem is significant. Vegetation affects the hydrological change process of the BWF and GWF at the microscale. This study can provide data support and scientific rules for ecosystem water resource management in the basin. [ABSTRACT FROM AUTHOR]

Swine influenza is an economically important respiratory disease in swine, but it also constantly poses a threat to human health. Therefore, developing rapid, sensitive, and efficient detection methods for swine influenza virus (SIV) is important. By aligning the haemagglutinin (HA) gene sequences of SIVs circulating in China over a 10-year period, an H1 primer-probe set targeting both Eurasian avian-like H1N1 (EA H1N1) and pandemic 2009 H1N1 ((H1N1)pdm09) lineages plus a H3 primer-probe set targeting the prevalent human-like H3N2 (HL H3N2) subtype were designed. Subsequently, a TaqMan-MGB-based duplex one-step real-time RT-PCR (RT-qPCR) assay was established and evaluated. The duplex RT-qPCR has a detection limit of 5 copies/μL of HA plasmid for EA H1N1, (H1N1)pdm09, and HL H3N2 subtype SIVs, and its overall detection sensitivity of 100% and specificity of 91.67% matches that of traditional virus isolation through chicken embryo inoculation using experimentally infected mouse lung samples. The method showed high repeatability both within run and between runs, and there was no cross-reactivity against several other porcine viruses that are commonly circulating in China. Furthermore, the duplex RT-qPCR method revealed a higher prevalence of subtype H1 than subtype H3 in 166 nasal swabs from pigs collected from one slaughterhouse between October and December 2019. This assay could be very helpful in the rapid differential detection and routine surveillance of EA H1N1, (H1N1)pdm09, and HL H3N2 SIVs in China. [ABSTRACT FROM AUTHOR]

Antibiotics have become a global public concern due to the widespread presence of antibiotic-resistant bacteria and genes. This study investigated the spatial and seasonal variation of conventional water quality parameters and 10 selected antibiotics in rivers inflowing into Taihu Lake. The results showed that total nitrogen, as a pollution driver factor, varied with the seasons, and higher concentrations of pollutants were generally found in the dry season compared with the wet season. For antibiotics, seven of them were detected in surface waters (n = 66) with detection frequencies (DFs) of 1.52–100% and eight antibiotics with DFs of 2.56–100% in sediments (n = 39). Sulfamethoxazole (SMZ, median: 1.47 ng/L), trimethoprim (TMP, median: 0.35 ng/L), and roxithromycin (ROX, median: 0.47 ng/L) with 100% DFs followed by erythromycin (ERY, median: 0.56 ng/L) with a DF of 90.91% accounted for a median percentage of 44.54%, 9.08%, 20.42%, and 13.16% of the ΣABs concentrations in surface waters. In contrast, enrofloxacin (ENR, median: 0.54 ng/g) and ROX (median: 0.29 ng/g) with 100% DFs accounted for a median percentage of 58.21% and 31.71% of the ΣABs concentrations in sediments. Antibiotics in surface waters were mainly related to T, DO, TN and NH 3 –N, but were mainly related to T, pH and TN for antibiotics in sediments. Furthermore, most of the detected antibiotics showed higher concentrations and more species of antibiotics in winter than in summer or autumn. Similarly, the ecological risk values of antibiotics showed higher in winter than in the other two seasons, whereas the overall risk levels were considered acceptable. [Display omitted] • High concentrations and ecological risk in the dry season than the wet season. • Total nitrogen was a pollution driver factor for conventional water quality parameters. • Strongly significant correlations were found among conventional water quality parameters and antibiotics. • The dominant antibiotic was SMX in surface water, ENR in sediments, whereas ROX for ecological risk. [ABSTRACT FROM AUTHOR]

The pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), a cotton pest probably native to Indo-Pakistan, invaded China at the beginning of the 20th century. Chinese P. gossypiella have been assumed to be the result of indiscriminate introductions from Pakistan and America by transport of cotton seed. We tested this long-held hypothesis and genotyped a total of 527 individuals from 14 sites at 13 microsatellite loci. We analyzed these data with traditional statistics as well as with Bayesian methods. The loci were, for the most part, highly polymorphic. The allelic richness of Chinese populations at six loci was greater than those of the Pakistani and American populations. Significant deficits of heterozygotes were recorded for all 14 populations, and null alleles were the most probable factor contributing to these deficits. Pairwise FST estimates showed that there was significant differentiation among the pooled Chinese, Pakistani, and American populations, and there was structure within most of the Chinese populations. The Bayesian analysis revealed that the combined Chinese, American, and Pakistani populations formed separate clusters, and the nine Chinese populations were divided into two clusters. Allelic frequency distributions showed that private and shared alleles within Chinese P. gossypiella were derived only partly from the Pakistani and American populations. The microsatellite-based genetic analyses suggested that the Chinese P. gossypiella populations originated from multiple sources. [ABSTRACT FROM AUTHOR]

1. Changes in the frequency of Cry1Ac resistance genes and shifts in tolerance of cotton bollworm, Helicoverpa armigera, to the Cry1Ac toxin were assessed using bioassays of F1 and F2 offspring of isofemale lines from Anci County of Hebei Province (a multiple-crop system including corn, soybean, peanut, and Bt cotton) and Xiajin County of Shandong Province (an intensive Bt cotton planting area) in Northern China during 2002–2005. 2. A conservative analysis of the overall results indicated that there was a small increase in the frequency of major, non-recessive resistance genes over time. 3. The relative average development ratings [RADR – growth rate of a line on a Bt diet in proportion to the growth rate on a non-Bt (NBT) diet] of the bollworm larvae in F1 tests increased significantly from year to year, indicating a gradual trend towards higher tolerance to Cry1Ac in the field populations. 4. There were also significant positive correlations between RADR of the lines in the F1 generation and the RADR of their F2 offspring, indicating that the tolerance was genetically based. 5. Quantitative genetic simulation analysis showed that resistance of H. armigera to Bt cotton in Xiajin could evolve to a high level in 11–15 years if no effective resistance management measures are carried out. [ABSTRACT FROM AUTHOR]

With rapid improvements in industrialization and urbanization, antibiotics are now extensively used to prevent and treat human and animal diseases and husbandry and aquaculture. Some research has been conducted to assess the environmental distribution and risk level of antibiotics, but their distribution remains largely uncharacterized. Thus, this study investigated the distribution and abundance of 39 antibiotics belonging to five groups, and their associated risks in surface water around Luoma Lake in the north of Jiangsu province, China. Nineteen antibiotics were detected, at a detection frequency (DF) ranging from 2.27% to 100%. The total antibiotics (ΣABs) concentrations ranged from 34.91 to 825.93 ng/L, with a median concentration of 195.45 ng/L. Among these antibiotics, chlortetracycline (DF: 100%; median: 172.02 ng/L) was the dominant antibiotic, accounting for a median percentage of 91.0% of ΣABs concentrations. Spearman rank correlation method found a significant correlation between clindamycin (DF: 72.7%; median: 2.01 ng/L) and lincomycin (DF: 79.5%; median: 4.58 ng/L). The ecological risk quotient (RQ) values for two out of 44 sampling sites were higher than 1, indicating a high risk; 11.4% of the RQ values fell between 0.1 and 1, indicating a medium risk. Moreover, roxithromycin was found to be the dominant contributor to the ecological risk, accounting for a median of 79.7% of ΣABs. However, the total non-carcinogenic (<6.54 × 10−4) and carcinogenic risks (<1.64 × 10−7) of ΣABs were negligible at the detected concentrations. Image 1 • Concentrations and distributions of 39 antibiotics around Luoma Lake were revealed. • Chlortetracyclin was found to be the dominant antibiotic, with a median of 172.02 ng/L. • Ecological risks of antibiotics were at medium level (11.4%) or slightly high level (4.6%). • Non-carcinogenic and carcinogenic risks of antibiotics were low at the detected concentrations. [ABSTRACT FROM AUTHOR]

Transgenic cotton that has been engineered to produce insecticidal toxins from Bacillus thuringiensis (Bt) and so to resist the pest cotton bollworm (Helicoverpa armigera) has been widely planted in Asia. Analysis of the population dynamics of H. armigera from 1992 to 2007 in China indicated that a marked decrease in regional outbreaks of this pest in multiple crops was associated with the planting of Bt cotton. The study area included six provinces in northern China with an annual total of 3 million hectares of cotton and 22 million hectares of other crops (corn, peanuts, soybeans, and vegetables) grown by more than 10 million resource-poor farmers. Our data suggest that Bt cotton not only controls H. armigera on transgenic cotton designed to resist this pest but also may reduce its presence on other host crops and may decrease the need for insecticide sprays in general. [ABSTRACT FROM AUTHOR]

The codling moth Cydia pomonella is a major pest of global significance impacting pome fruits and walnuts. It threatens the apple industry in the Loess Plateau and Bohai Bay in China. Sterile insect technique (SIT) could overcome the limitations set by environmentally compatible area-wide integrated pest management (AW-IPM) approaches such as mating disruption and attract-kill that are difficult to suppress in a high-density pest population, as well as the development of insecticide resistance. In this study, we investigated the effects of X-ray irradiation (183, 366, 549 Gy) on the fecundity and fertility of a laboratory strain of C. pomonella , using a newly developed irradiator, to evaluate the possibility of X-rays as a replacement for Cobalt60 (60Co- γ) and the expanded future role of this approach in codling moth control. Results show that the 8th-day is the optimal age for irradiation of male pupae. The fecundity decreased significantly as the dosage of radiation increased. The mating ratio and mating number were not influenced. However, treated females were sub-sterile at a radiation dose of 183 Gy (20.93%), and were almost 100% sterile at a radiation dose of 366 Gy or higher. Although exposure to a radiation dose of 366 Gy resulted in a significant reduction in the mating competitiveness of male moths, our radiation biology results suggest that this new generation of X-ray irradiator has potential applications in SIT programs for future codling moth control. [ABSTRACT FROM AUTHOR]

The fall armyworm Spodoptera frugiperda, an invasive insect pest native to the Americas, has established populations throughout eastern China. The North China Plain—a key corn‐producing area in East China with a unique topography—was invaded by fall armyworm in 2019 and is seriously threatened by this migratory pest. However, the spatiotemporal extent of the migratory movements of fall armyworm from the North China Plain remains poorly understood. Using an air transport‐based trajectory modeling approach that incorporates flight behavior, we simulated the potential nocturnal migration trajectories of fall armyworm from the North China Plain based on historical meteorological data from June to October of 2015–2019, and examined the night‐time atmospheric conditions associated with their possible flights. The emigration patterns showed monthly variation in the main landing area and common migration direction. The displacement of newly emerged moths from the North China Plain was concentrated in the Northeast China Plain (including Liaoning, Jilin and Heilongjiang provinces) before late summer, after which they were most likely to undertake return flights to the south (especially into Hubei, Anhui and Hunan provinces). This southwest‐northeast aerial migration corridor follows the topography of East China and is affected by the East Asian monsoon. These topographic‐atmospheric conditions have resulted in the North China Plain becoming a key stopover for fall armyworm populations engaging in multigenerational long‐distance migration across East China. These findings contribute to our knowledge of fall armyworm migration and will aid in the implementation of management and control strategies against this highly migratory agricultural pest. [ABSTRACT FROM AUTHOR]

1 A network of light-traps, an aerial net carried by kytoon (balloon) and two entomological radars were used to investigate whether ground beetles migrate nocturnally through China. The network-wide, simultaneous sudden increase in light trap catches, and after subsequent decrease, indicated a seasonal long-distance night migration of ground beetles, with Pseudoophonus griseus (Panzer) predominant, in August. 2 Aerial net trapping indicated that carabids were able to ascend to altitudes of at least 200 m and become windborne. Radar observations indicated that the migratory beetles formed high-density layer concentrations at approximately 200–300 m. 3 These concentrations were coincident with the top of the temperature inversion and a wind speed maximum, which suggested that the carabids tended to select warm, fast moving air for their long-distance migration. 4 The ground beetles orientated and displaced towards the downwind direction in southerly winds. Their air speed decreased as the tailwind increased and, thus, migrating beetles appeared to be conserving energy. 5 The mean ± SD displacement speed (ground speed) and air speed were 6.85 ± 1.73 m/s ( n= 172) and 4.45 ± 1.54 m/s ( n= 172), respectively. The duration of flight, estimated from the variation in area density derived from radar data, was approximately 9–10 h, indicating that the beetles might migrate hundreds of kilometres in a single flight. [ABSTRACT FROM AUTHOR]

Eutrophication pollution seriously threatens the sustainable development of Lake Taihu, China. In order to identify the primary parameters of water quality and the potential pollution sources, the water quality dataset of Lake Taihu (2010–2014) was analyzed with the water quality index (WQI) and multivariate statistical analysis methods. Principle component analysis/factor analysis (PCA/FA) and correlation analysis screened out five significant water quality indicators, i.e. potassium permanganate index (COD Mn), total nitrogen (TN), total phosphorus (TP), chloride ion (Cl−) and dissolved oxygen (DO), to represent the whole datasets and evaluate the water quality with WQI. Since northwestern of Lake Taihu was the most heavily polluted area, the parameters of the water quality were analyzed to further explore the potential sources and their contributions. Five potential pollution sources of northwestern lake were identified, and the contribution rate of each pollution source was calculated by the absolute principal component score-multiple linear regression (APCS-MLR) and positive matrix factorization (PMF) models. In brief, the PMF model was more suitable for pollution source apportionment of the northwestern lake, and the contribution rate was ranked as agricultural non-point source pollution (26.6%) > domestic sewage discharge (23.5%) > industrial wastewater discharge and atmospheric deposition (20.6%) > phytoplankton growth (16.0%) > rainfall or wind disturbance (13.4%). This study might provide useful information for the optimization of water quality management and pollution control strategies of Lake Taihu. Image 1 • PCA/FA and correlation analysis screened out primary water quality parameters. • WQI and CA identified spatiotemporal distribution characteristics of water quality. • PCA/FA identified potential pollution sources in the heavily polluted area. • The APCS-MLR and PMF figured out contributions of pollution sources in distinct areas. [ABSTRACT FROM AUTHOR]

• A macroinvertebrate-based multimetric index (MMI) was developed for shallow lakes. • The MMI is comprised of three taxonomic and two functional metrics. • The MMI could capture the influence of eutrophication on lake ecological status. • Functional metrics could complement the information provided by taxonomic metrics. Benthic macroinvertebrates have a long history of use in environmental monitoring. However, macroinvertebrate-based multimetric approach has not been well developed to assessment aquatic ecosystems in China, particularly in lake ecosystems. Eutrophication has been recognized as one of the main pressures affecting shallow lakes in China and elsewhere and it is thus desirable to quantify its effects on ecological integrity of lake ecosystems. Here, 41 subtropical shallow lakes in the Eastern Plain Lake Ecoregion of China were sampled and defined as three groups along eutrophication gradients. A macroinvertebrate-based multimetric index, consisting of three taxonomic metrics (No. of Gastropoda taxa, biological pollution index, and Margalef index) and two functional metrics (functional evenness and relative abundance of deposit feeder) was developed based on the datasets of the 41 lakes, and the results of multiple linear regression showed that the MMI was significantly related to the concentration of TP and macrophyte cover. This finding indicated that the MMI could characterize the influence of eutrophication on lake ecosystems. Our results also indicated that functional metrics could complement the information provided by taxonomic metrics, and we recommend to properly use functional metrics in lake biomonitoring. The macroinvertebrate-based MMI proposed here is the first attempt using biological quality element to assess the ecological status of shallow lakes in the view of eutrophication at the regional scale and could provide complementary information to traditional water quality assessment for the development of management strategies. [ABSTRACT FROM AUTHOR]

Many insects such as the crop pest Agrotis ipsilon (black cutworm) migrate seasonally to exploit suitable breeding and winter habitats. The migration of a crop pest also increases the risk of sudden outbreaks. Knowledge about insect migration thus is important for developing a forecasting and warning system for migratory pests. Here we used directional flight devices to study the orientation behavior of A. ipsilon in China during the northward and southward migratory periods and showed that the insects during each period exhibited a common cardinal orientation. Northward migratory moths were oriented at an orientation angle mean of 24.4° and the southward at 205.17°. Expression levels of cryptochrome and magnetoreceptor genes in migratory populations were higher than in a reared population and higher in the southward migratory population than in the northward. These findings provide a physiological and molecular basis for further study of the migratory behavior of the black cutworm and potential control of this pest. [ABSTRACT FROM AUTHOR]

Atractylodis Macrocephalae Rhizoma (AMR) is one of commonly used medicinal and edible herbs in China. It is often sulfur-fumigated during post-harvest processing. Carbohydrates are important active components of AMR. However, it is unknown whether sulfur-fumigation would induce changes on carbohydrates. Here, carbohydrates including polysaccharides, oligosaccharides and free monosaccharides were comprehensively analyzed to characterize the quality changes of sulfur-fumigated AMR. Determination of both homemade sulfur-fumigated AMR samples and commercial samples from market revealed that sulfur-fumigation did not affect molecular weight distribution of polysaccharides, but altered polysaccharides content and its ratios of constituent monosaccharides, especially glucose (Glc) and fructose (Fru), as well as the contents of oligosaccharides DP2–10 and free monosaccharide Fru. Moreover, the variations enhanced with the increasing of residual SO 2 content. The potential transformation mechanisms could be due to the hydrolysis of polysaccharides. The research outcomes could provide a chemical basis for the safety and efficacy evaluations of sulfur-fumigated AMR. [Display omitted] • Multi-chromatographic technology methods were integrated to characterize carbohydrates components of AMR. • Impact of sulfur-fumigation on carbohydrates of AMR was evaluated. • Sulfur-fumigation decreased the content of polysaccharides, whereas increased that of oligosaccharides and free fructose. • The variations of carbohydrates enhanced with the increase of SO 2 residual amounts. • The potential transformation mechanisms might be the hydrolysis of polysaccharides into oligosaccharides and monosaccharides. [ABSTRACT FROM AUTHOR]

Abstract: It is generally accepted that in most insects adults are sexually immature when they initiate migration and that migratory behaviour terminates with the onset of sexual maturation. However, a few studies examining the mating status of field collected moths have suggested that sexually mature individuals may continue migrating, but in these cases it was impossible to completely eliminate the possibility that the mated females captured came from local, non-migrant populations. In this study we examined the ovarian development of Mythimna separata females captured using a vertical pointing searchlight trap on Beihuang Island in the Bohai Gulf, China, a site >40km from land. Moths were collected from May to October from 2003 to 2008 in order to test the hypothesis that the onset of sexual maturation resulted in the termination of migratory behaviour. While females at the end of the summer had little ovarian development and were unmated, a significant proportion of those migrating northward in the early summer had developed ovaries and often had at least one spermatophore. Given that theses insects were captured while flying up to 500m above sea level, at a site with no local populations, the findings would not support the hypothesis and suggest that both ovarian development and mating may occur during migration. [Copyright &y& Elsevier]

The fall armyworm (FAW), native to the Americas, has rapidly invaded the whole of Southern China since January 2019. In addition, it can survive and breed in the key maize- and rice- growing area of the Yangtze River Valley. Furthermore, this pest is also likely to continue infiltrating other cropping regions in China, where food security is facing a severe threat. To understand the potential infestation area of newly-invaded FAW from the Yangtze River Valley, we simulated and predicted the possible flight pathways and range of the populations using a numerical trajectory modelling method combining meteorological data and self-powered flight behavior parameters of FAW. Our results indicate that the emigration of the first and second generations of newly-invaded FAW initiating from the Yangtze River Valley started on 20 May 2019 and ended on 30 July 2019. The spread of migratory FAW benefitted from transport on the southerly summer monsoon so that FAW emigrants from the Yangtze River Valley can reach northern China. The maize-cropping areas of Northeastern China, the Korean Peninsula and Japan are at a high risk. This study provides a basis for early warning and a broad picture of FAW migration from the Yangtze River Valley. [ABSTRACT FROM AUTHOR]