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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]

The water conservation function of ecosystems is a research hot spot in the field of water resources, and it is also an important ecological service function of terrestrial ecosystems and a key point in eco-hydrology research. With the increasing frequency of human activities and climate change, how to reveal the response of ecosystem water conservation function to the changing environment is a scientific problem that needs to be urgently addressed in ecological hydrology research. To reveal the eco-hydrological processes under the changing environment, this study was based on the distributed hydrological model (SWAT) and used water conservation amount (WCA) as an indicator to assess the water conservation capacity of ecosystems. Scenario analysis and statistical analysis were also used to determine the spatial and temporal evolution of the WCAs of farmland, forest, and grassland ecosystems under a changing environment and to further investigate the influence mechanisms of land use change and climate change on the WCA. The findings show that (1) the climate conditions in the Hanjiang watershed have determined the distribution pattern of the ecosystem's WCA. The spatial distribution patterns of the WCA of each ecosystem differed significantly between the dry season and the wet season. Under the combined influence of human activities and climate change, there was no significant change in the spatial distribution pattern of the WCA. (2) Climate change patterns, which were dominated by precipitation and influenced by evapotranspiration, determined the changes in the WCA of ecosystems. In addition, there were significant spatial differences in the response of the watershed WCA under changing environments in the dry season. Differences in land use type and local climate change were the main reasons for such differences. (3) There were differences in the WCA and the response to changing environments among ecosystems. Forest ecosystems had the highest WCA; grassland ecosystems were the most sensitive to land use change. This study can provide a theoretical basis for alleviating the increasingly serious water resource problems in the basin and ensuring water and ecological security in the basin. [ABSTRACT FROM AUTHOR]

Bacterioplankton play a vital role in maintaining the functions and services of lake ecosystems. Understanding the diversity and distribution patterns of bacterioplankton, particularly the presence of potential pathogenic bacterial communities, is crucial for safeguarding human health. In this study, we employed 16S rRNA gene amplicon sequencing to investigate the diversity and geographic patterns of bacterioplankton communities, as well as potential pathogens, in eight volcanic lakes located in the Arxan UNESCO Global Geopark (in the Greater Khingan Mountains of China). Our results revealed that the bacterial communities primarily comprised Bacteroidota (45.3%), Proteobacteria (33.1%), and Actinobacteria (9.0%) at the phylum level. At the genus level, prominent taxa included Flavobacterium (31.5%), Acinetobacter (11.0%), Chryseobacterium (7.9%), and CL500-29 marine group (5.6%). Among the bacterioplankton, we identified 34 pathogen genera (165 amplicon sequence variants [ASVs]), with Acinetobacter (59.8%), Rahnella (18.3%), Brevundimonas (9.6%), and Pseudomonas (5.8%) being the most dominant. Our findings demonstrated distinct biogeographic patterns in the bacterial communities at the local scale, driven by a combination of dispersal limitation and environmental factors influenced by human activities. Notably, approximately 15.3% of the bacterioplankton reads in the Arxan lakes were identified as potential pathogens, underscoring the potential risks to public health in these popular tourist destinations. This study provides the first comprehensive insight into the diversity of bacterioplankton in mountain lake ecosystems affected by high tourist activity, laying the groundwork for effective control measures against bacterial pathogens. [Display omitted] • Distinct biogeographic patterns of bacterioplankton were found at the local scale. • Both dispersal limitation and human-induced factors shape bacterial communities. • 34 pathogenic bacterial genera were identified in Arxan volcanic lakes. • Acinetobacter , Rahnella , Brevundimonas , and Pseudomonas dominated in Arxan lakes. • High abundance of pathogens (15.3%) highlights health risks in touristic lakes. [ABSTRACT FROM AUTHOR]

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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]

Heavy metal pollution in lake systems has arisen plenty of threats for public health because of its high toxicity, persistence, and bioaccumulation. Whereas heavy metals are inextricably linked with bioavailability in pore water and overlying water. Lake Jiaogang is classified as an important water-carrying lake situated in the northern part of the Anhui Province China. In recent years, water quality in this lake declined due to increasing fishery aquaculture, livestock, and tourism. This study aims to bring insight into the interactions of heavy metal elements across sediment-water interface in Lake Jiaogang. Four representative regions were selected, more than ten heavy metals were chosen to quantify by the Community Bureau of Reference, diffusive gradient in thin-film (DGT), and high-resolution pore water equilibrators. The results showed that most heavy metals corresponded with the reducible fraction, acid-soluble fraction, and oxidizable fraction in the Eastern area (sample 3#) and aquaculture area (sample 4#) were higher than that of emergent plant area (sample 1#), and floating plant area (sample 2#). The average fluxes of heavy metals (except Ni and Zn in sample 3#, F value > 0 pg/cm2/d) in the four sampling sites were observed in the lower reaches (F value < 0 pg/cm2/d). The vertical distribution of heavy metals was extracted by DGT, such as As (exclude 2#), Co, Fe, Mn, and Zn (contain 4#) showed an increased content with increasing depth in the four sampling sites. In the pore and overlying water, concentrations of heavy metals from the sample 3# and 4# were higher than those of sample 1# and 2#. Heavy metal pollution in anthropogenic activity areas was higher than those in areas with ecological vegetation, and risk control in this area should be strengthened. [Display omitted] • Interactions of heavy metal elements across sediment-water interface was observed. • Vertical distribution of heavy metals was quantified by DGT and HR-Peeper. • Significant positive correlation was revealed between the concentration of Mn and As. • Relationships of the heavy metals were revealed between sampling sites and depth. [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 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]

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]

Emerging contaminants, including antibiotics, antibiotic-resistant bacteria (ARB), and extracellular antibiotic resistance genes (eARGs), have been detected in large numbers in the aquatic environment. The effects of emerging contaminants on bacterial communities in marine sediments are not well studied. In this study, the effects of emerging contaminants (antibiotics, ARB, and eARGs) on the variations of bacterial populations in marine sediments of the Bohai Sea, Yellow Sea, East China Sea, and South China Sea were investigated. The results showed that the abundance of the host bacterial phylum Probacteria in the marine sediments of the Bohai Sea was the lowest among the four seas after exposure to different antibiotics, ARB, and eARGs. The inputs of exogenous antibiotics and resistance genes significantly affected the community function, resulting in significant differences in community abundance at the genus level. The abundance of Halomonas, Sulfitobacter, and Alcanivorax in the four sea areas displayed noteworthy differences in response to the addition of exogenous antibiotics and eARGs. These findings contribute to a more comprehensive understanding of the intricate interplay between emerging contaminants and the dynamics of bacterial communities in natural ecosystems., 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 © 2023 Elsevier Inc. All rights reserved.)

Studying the historical and future trends of water resources in a basin and explaining the causes of water resource changes is very important, which is key to the management of water resources in a basin. The Hanjiang River Basin is an important water supply source for southwestern Fujian and eastern Guangdong, but it has an uneven spatial and temporal distribution of water resources and an outstanding conflict between supply and demand. In this study, the SWAT model was used to simulate the conditions of the Hanjiang River Basin in the last 50 years, using long time series climate data to study the characteristics and driving mechanism of water resources trend change. The results show that the water resources in the basin have not increased significantly in the last 50 years, but evapotranspiration has increased significantly. The forecast results for water resources in the future are reduced. The water resource changes in the basin have been unevenly distributed in the last 50 years. Climate change has been the main factor in total water resource change in the basin, while the difference in water resource change trends within the basin is caused by land use. The key reason for the decrease in water resources in the Hanjiang River Basin is the significant increase in evapotranspiration due to the significant increase in temperature. If this situation continues, the available water resources in the basin will continue to decline. In fact, many basins around the world are currently likely to have such problems, such as the 2022 summer drought in the Danube River Basin in Europe and the Yangtze River Basin in China, so this article is informative and representative of future water resources management in the basin.

Antibiotics, antimicrobial resistance determinants and human pathogens are new types of environmental pollutants that pose a great threat to human health. Wastewater treatment plants (WWTPs) are important sources of novel pollutants; however, few studies have investigated their impact on surrounding natural water. Therefore, this study used a WWTP as the entry point to explore WWTP removal efficiency of antibiotics, antimicrobial resistance determinants and human pathogens and further analyze the impact of WWTP effluent on receiving waters. The investigated WWTP had a good removal effect on fluoroquinolones, macrolides, lincomycin, sulfanilamide, tetracycline and chloramphenicol antibiotics in wastewater, and the concentration of antibiotics in the WWTP's effluent was reduced by >80% relative to the influent. In addition to cmlA, the effect of the WWTP on antimicrobial resistance determinants removal was poor, although the effluent from the WWTP had no effect on the abundance of antimicrobial resistance determinants in the receiving water. However, with the dilution of receiving water, the abundance of antimicrobial resistance determinants gradually decreased. The WWTP could reduce the abundance of bacteria by 1000 times from influent water to effluent water. The major bacteria in the influent and effluent were Bacteroidetes and Proteobacteria. After effluent is discharged into receiving water, Cyanobacteria proliferate in large quantities, which can affect the microbial structure in the environment.The abundance of Acinetobacter, which was the predominant potential human pathogen in local wastewater, decreased dramatically after wastewater treatment. We also conducted an ecological risk assessment of the antibiotics identified and found that the ecological risk AZM and CLR posed to aquatic organisms was high. Overall, we identified the efficiency of WWTP control of antibiotics, antimicrobial resistance determinants and potential human pathogens and the impact of WWTP effluent on receiving water and provided data to support the control of the investigated pollutants., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The strict environmental management has been implemented in Taihu Basin to reduce the surface water contamination; however, the effectiveness of the management actions has not been comprehensively evaluated. In the present study, 364 samples were collected during four campaigns over a span of one year from surface water, municipal wastewater treatment plants (MWWTPs), industrial wastewater treatment plants (IWWTPs), industrial enterprises, and aquaculture in a typical region in the Upper Taihu Basin. Overall concentration, temporal variation and spatial distribution of 16 PAHs in surface water and various pollution sources were evaluated and the potential pollution sources were identified. Results showed that concentrations of individual PAHs in the surface water ranged from less than the limit of quantification (LOQ) to 949 ng L -1 , indicating a reduction of PAH contamination level after the implementation of environmental management actions. Influent of MWWTPs and wastewater from industrial enterprises exhibited relatively high ∑PAHs concentrations (mean: 880 ng L -1 and 642 ng L -1 , respectively); these samples also exhibited a similar seasonal variation as well as composition of PAH congeners to those found in surface water, and therefore were designated as the main emission sources of PAHs in the studied region. Additional source apportionment using principal component analysis was also conducted to verify the proposed sources and diagnose other pollution sources. The findings provided a thorough understanding of PAH pollution, especially its major emission sources, in a typical region with pollution-intensive industries after the implementation of strict environmental management., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

To illustrate the contribution of phytoplankton-derived particulate organic matter (PPOM) to endogenous phosphorus (P) cycling and its effects on cyanobacteria blooms, PPOM characteristics, the degradation mechanism, and the growth of P-deficient Microcystis aeruginosa were studied in Lake Taihu. Results showed that PPOM is the most important P pool in the water column during cyanobacteria bloom, accounting for more than 80% of the total P (TP) in the water. During PPOM degradation, the particulate orthophosphate (Ortho-P) is the main species of P release from PPOM in the early degradation stage. The variations of polyphosphate (Poly-P) and phosphodiesters (Diester-P) contents were most significant, which were degraded completely within four days and eight days. Cell density and growth rate of M. aeruginosa using PPOM as P source were similar to those growing on Na 2 HPO 4 . The above results show that P in PPOM can be converted into available P by degradation, thus promoting the growth of M. aeruginosa . Therefore, the contribution of P release from PPOM degradation needs to be paid attention to in lake eutrophication control in the future.

To analyze genetic characters of migratory dragonflies, we used 10 microsatellite markers and a partial sequence of the mitochondrial gene Cytb to investigate genetic diversity and demographic history among 19 populations of P. flavescens in eastern the monsoon region of China. In a Bayesian clustering analysis of the microsatellite data, three distinct clades were present, and each population consisted of a mixture of individuals from the three clusters. An AMOVA of the data from both the microsatellite loci and Cytb revealed that genetic variation was mainly within each population. For the 543 individuals from the 19 regions, 77 unique haplotypes were obtained by DnaSP 4.0, and a median-joining network showed no obvious geographical pattern and displayed high gene flow and minimal population genetic structure among the 19 populations. According to a Mantel test, there was no significant association between genetic distance and geographic distribution and no isolation by distance. Mismatch distribution and neutrality tests showed no demographic expansion for the 19 populations. Microsatellite and mitochondrial DNA data suggested there was high gene flow and low differentiation among the populations. These results will help provide valuable information to study the migratory route of insects, especially important agricultural pests.

Colloidal particles are omnipresent in lake sediments and substantially influence the retention, transportation, and fate of contaminants in lake ecosystems. In this study, the abundance, chemical composition and adsorption behavior of sedimentary colloids (including total and inorganic colloids) from different ecological regions, were for the first time investigated via ultrasonic extraction, spectral analysis and batch absorption experiments. Results showed that the extraction efficiencies of sedimentary colloids showed an ultrasonic energy-dependent enhancement, and the algae-dominated area contained comparable colloidal abundance with the macrophyte-dominated area (i.e., 198.5 vs. 183.3 mg/g). Despite the different ecosystems, these sedimentary colloids usually had a wide size distribution of 30-200 nm, and were characterized with montmorillonite-, kaolin-, volkonskoite-, and quartz-rich chemical compositions. Batch experiment showed that the total pristine colloids exhibited higher adsorption capacity for Pb(II) than the inorganic colloids both for the macrophyte- and algae-dominated sediments, and the adsorption process followed pseudo-second-order kinetics and Langmuir isotherm, irrespective of different colloidal types. Thus, sedimentary colloids can immobilize the heavy metals in sediment and decrease their release into the water column, which can be considered as a sink for contaminants. This study highlighted the significance of sedimentary colloids in determining the physicochemical properties of lake sediments and in evaluating the environmental behavior and fate of contaminants in lake ecosystems., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Spatial and seasonal variations of particulate phosphorus (PP) in a large shallow, eutrophic Lake Taihu with different ecotypes (including a phytoplankton-dominated zone, lake center zone, estuary zone and macrophyte-dominated zone) were investigated. The results showed that particulate organic phosphorus (POP) was the dominant form of PP (>88.0%). The concentration of POP showed higher levels in the bloom-sensitive northwestern zone (phytoplankton-dominated zone and estuary zone) during warm seasons, phytoplankton blooms and input of exogenous particulate matter were the main sources of POP in the lake water. Based on 31 P nuclear magnetic resonance ( 31 P NMR) analysis, orthophosphate (Ortho-P) was the dominant molecular species of PP and positively correlated with soluble reactive phosphorus (SRP) ( p < 0.01). This suggested that the release of Ortho-P from suspended particulate matter (SPM) was the main source of SRP in the lake water. Pyrophosphate (Pyro-P), which is regarded as a highly labile species of P compounds, represented a large fraction of PP, and its significant positive correlations with chlorophyll a (Chl a ), indicated that the concentration of Pyro-P could be used as an important indicator for the degree of eutrophication of Lake Taihu. These results proved that PP in lake water was a significant factor supporting lake eutrophication and must be controlled.

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.