Assessing lake water quality during COVID-19 era using geospatial techniques and artificial neural network model.

The present study evaluates the impact of the COVID-19 lockdown on the water quality of a tropical lake (East Kolkata Wetland or EKW, India) along with seasonal change using Landsat 8 and 9 images of the Google Earth Engine (GEE) cloud computing platform. The research focuses on detecting, monitoring, and predicting water quality in the EKW region using eight parameters-normalized suspended material index (NSMI), suspended particular matter (SPM), total phosphorus (TP), electrical conductivity (EC), chlorophyll-α, floating algae index (FAI), turbidity, Secchi disk depth (SDD), and two water quality indices such as Carlson tropic state index (CTSI) and entropy­weighted water quality index (EWQI). The results demonstrate that SPM, turbidity, EC, TP, and SDD improved while the FAI and chlorophyll-α increased during the lockdown period due to the stagnation of water as well as a reduction in industrial and anthropogenic pollution. Moreover, the prediction of EWQI using an artificial neural network indicates that the overall water quality will improve more if the lockdown period is sustained for another 3 years. The outcomes of the study will help the stakeholders develop effective regulations and strategies for the timely restoration of lake water quality.

The genetic architecture of phenotypic diversity in the Betta fish (Betta splendens).

The Betta fish displays a remarkable variety of phenotypes selected during domestication. However, the genetic basis underlying these traits remains largely unexplored. Here, we report a high-quality genome assembly and resequencing of 727 individuals representing diverse morphotypes of the Betta fish. We show that current breeds have a complex domestication history with extensive introgression with wild species. Using a genome-wide association study, we identify the genetic basis of multiple traits, including coloration patterns, the "Dumbo" phenotype with pectoral fin outgrowth, extraordinary enlargement of body size that we map to a major locus on chromosome 8, the sex determination locus that we map to dmrt1, and the long-fin phenotype that maps to the locus containing kcnj15. We also identify a polygenic signal related to aggression, involving multiple neural system-related genes such as esyt2, apbb2, and pank2. Our study provides a resource for developing the Betta fish as a genetic model for morphological and behavioral research in vertebrates.

Transcriptome comparison for identification of pigmentation-related genes in different color varieties of Siamese fighting fish Betta splendens.

Transcriptome comparison was performed to identify genes expressed in skin, muscle and tails of mono-color (Red, Blue, Black, White and Yellow), bi-color (Cambodian) and multi-color (Marble) varieties of Siamese fighting fish Betta splendens. In total, 163,140 unigenes covering 26.348 Gb were found. Of these, 93,899 (57.55 %) unigenes significantly matched at least one database. In total, 5039 differentially expressed genes (DEGs) were found where 2415 genes (47.93 %) showed higher expression and 2624 genes (52.07 %) showed lower expression for all pairwise comparisons. DEGs between paired color varieties were 133-443. Of these, 38-220 genes were more highly expressed while 37-280 genes were more lowly expressed relative to the compared varieties. A total of 897 sequences (148 genes) significantly matched pigmentation-related genes of Danio rerio (E-value < 1e-06). Of these, 19 DEGs were identified. Examples are tyrosinase-related protein 1a (BsTyrp1a), epidermal growth factor receptor (BsEgfr) and neurofibronin 1a (BsNf1a). Moreover, 711,123 SNPs were identified and 1365 of these were located in pigmentation-related genes. Interestingly, an A > C474 SNP in the gene BsTrpm7 and an indel (position 3571) in the BsItgb1a gene were found only in Cambodian. A C > T2520 SNP in BsFzd4 and 10 of 11 SNPs in BsTyrp1a were found only in Black. Different expression levels (P < 0.05) were found for tyrosinase (BsTyr), BsTyrp1a, BsNf1a and BsEgf1 among skin, body muscle and tails of the same variety and among the same tissues of different varieties (Red, Green, Blue, Black, Cambodian and Multi-colors, N = 5 each).

Full-Length Transcriptome Sequences Provide Insight Into Hermaphroditism of Freshwater Pearl Mussel Hyriopsis schlegelii.

The freshwater mussel Hyriopsis schlegelii is a cultured bivalve in China, and the quality of the pearls produced is affected by the type of gonads. However, because of the lack of a published genome and the complexity of sex determination, research on sex reversal and development of this species is limited. In this study, Illumina RNA-seq and PacBio Isoform Sequencing (Iso-Seq) were combined to analyze the gonads of H. schlegelii. A total of 201,481 high-quality transcripts were generated. The study identified 7,922 differentially expressed genes in three comparison group (females versus males, hermaphrodites versus females, and hermaphrodites versus males). Twenty-four genes were identified as potential sex-related genes, including sox9 and wnt4 involved in sex determination, and vtg, cyp17a1 and 17ß-hsd2 involved in gonadal development. We also speculated a possible pathways for the formation of hermaphroditism in H. schlegelii. The data provide a clear view of the transcriptome for H. schlegelii gonads and will be valuable in elucidating the mechanisms of gonad development.

A Lycium barbarum extract inhibits ß-amyloid toxicity by activating the antioxidant system and mtUPR in a Caenorhabditis elegans model of Alzheimer's disease.

Lycium barbarum, a traditional Chinese medicine, has been shown to have antioxidant properties and has a protective effect in many diseases related to oxidative stress, such as neurodegenerative diseases, cardiovascular diseases, and cancer. Although the neuroprotective effects of L. barbarum extract (LBE) have been reported in several studies, the underlying molecular mechanisms are still unclear. In this study, the transgenic Caenorhabditis elegans strain CL2006 was used to investigate the function and molecular mechanism of an LBE in Alzheimer's disease (AD). LBE had high antioxidant potential and effectively delayed Aß-induced paralysis in the CL2006 strain. LBE inhibited the production of excessive reactive oxygen species by inducing the SKN-1-mediated antioxidant system, thereby inhibiting the generation of Aß and inhibiting mitochondrial damage. Importantly, LBE reduced Aß levels by inducing FSHR-1-mediated activation of the mtUPR. Therefore, our study not only reveals a new mechanism of LBE in the treatment of AD but also identifies a novel strategy for the treatment of AD by enhancing the mtUPR.

Diagnoses of two new species of Parosphromenus (Teleostei: Osphronemidae) from Bangka Island and Kalimantan, Indonesia.

We describe two new species of Parosphromenus from Indonesia based on morphological and molecular diagnoses. Parosphromenus juelinae, sp. nov., occurs on Bangka Island. Its unpaired fin coloration is similar to that of P. deissneri, but it differs from the latter in having a rounded caudal fin with a non-filamentous branched median ray and a smaller anal fin. Although the new species has the same caudal fin structure as P. bintan, it can be distinguished from the latter by its distinct unpaired fin coloration and the intense red color on the body flanks. Parosphromenus kishii, sp. nov., is found only in a single river system in Kalimantan Tengah. It is distinguished from all other congeners by the unique coloration of its caudal fin. A phylogenetic tree based on the cytochrome b (cytb) gene indicates that the two new species are distinct monophyletic groups constituting distinct phylogenetic branches from their congeners. Cytochrome b Genetic distances between Parosphromenus juelinae, sp. nov., and Parosphromenus kishii, sp. nov., and the other taxa in the phylogenetic tree range from 2.44% to 19.52% and from 8.65% to 17.28%, respectively.

Chromosome-scale assembly and high-density genetic map of the yellow drum, Nibea albiflora.

The yellow drum (Nibea albiflora) is an economically important sciaenid fish in East Asian countries. In this study, we sequenced and assembled a near-complete gynogenetic yellow drum genome. We generated 45.63 Gb of Illumina short-reads and 80.27 Gb of PacBio long-reads and assembled them into a 628.01-Mb genome with a contig N50 of 4.42 Mb. Twenty-four chromosomes with a scaffold N50 of 26.73 Mb were obtained using the Hi-C analysis. We predicted a set of 27,069 protein-coding genes, of which 1,581 and 2,583 were expanded and contracted gene families, respectively. The most expanded genes were categorised into the protein binding, zinc-ion binding and ATP binding functional pathways. We built a high-density genetic linkage map that spanned 4,300.2 cM with 24 linkage groups and a resolution of 0.69 cM. The high-quality reference genome and annotated profiles that we produced will not only increase our understanding of the genetic architecture of economic traits in the yellow drum, but also help us explore the evolution and unique biological characteristics of sciaenid fishes.

Reconstructing high-resolution gridded precipitation data using an improved downscaling approach over the high altitude mountain regions of Upper Indus Basin (UIB).

Understanding the basin-scale hydrology and the spatiotemporal distribution of regional precipitation requires high precision, as well as high-resolution precipitation data. We have made an attempt to develop an Integrated Downscaling and Calibration (IDAC) framework to generate high-resolution (1 km × 1 km) gridded precipitation data. Traditionally, GWR (Geographical weighted regression) model has widely been applied to generate high-resolution precipitation data for regional scales. The GWR model generally assumes a spatially varied relationships between precipitation and its associated environmental variables, however, the relationships need to remain constant (fixed) for some variables over space. In this study, a Mixed Geographically Weighted Regression (MGWR) model, capable of dealing with the fixed and spatially varied environmental variables, is proposed to downscale the Original-TRMM precipitation data from a coarse resolution (0.25o × 0.25o) to a high-resolution (1 km × 1 km) for the period of 2000-2018 over the Upper Indus Basin (UIB). Additionally, accuracy of the downscaled precipitation data was further improved by merging it with the recorded data from rain gauge stations (RGS) using two calibration approaches such as Geographical Ratio Analysis (GRA) and Geographical Difference Analysis (GDA). We found MGWR to perform better given its higher R2 and lower RMSE and bias values (R2 = 0.96; RMSE = 56.01 mm, bias = 0.014) in comparison to the GWR model (R2 = 0.95; RMSE = 60.76 mm, bias = 0.094). It was observed that the GDA and GRA calibrated-downscaled precipitation datasets were superior to the Original-TRMM, yet GRA outperformed GDA. Annual precipitation from downscaled and calibrated-downscaled datasets was further temporally downscaled to obtain high-resolution monthly and daily precipitations. The results revealed that the monthly-downscaled precipitation (R2 = 0.82, bias = -0.02 and RMSE = 11.93 mm/month) and the calibrated-downscaled (R2 = 0.89, bias = -0.006 and RMSE = 9.19 mm/month) series outperformed the Original-TRMM (R2 = 0.72, bias = 0.14 and RMSE = 19.8 mm/month) as compared to the RGS observations. The results of daily calibrated-downscaled precipitation (R2 = 0.79, bias = 0.001 and RMSE = 1.7 mm/day) were better than the Original-TRMM (R2 = 0.64, bias = - 0.12 and RMSE = 6.82 mm/day). In general, the proposed IDAC approach is suitable for retrieving high spatial resolution gridded data for annual, monthly, and daily time scales over the UIB with varying climate and complex topography.

A large-scale comparison of meat quality and intramuscular fatty acid composition among three Chinese indigenous pig breeds.

Derived from the long historical natural and artificial selection, Chinese indigenous pigs have formed their own special meat characteristics. We herein systematically evaluated 14 meat characteristics and 15 fatty acid composition traits on three Chinese local pig breeds. The experimental pigs were produced by crossing design covering all sire genealogy and most of dam genealogy in each of the three breeds' seed conservation farms. All animals were reared in the same standardized housing and feeding conditions. A Comparison study showed that most of the investigated meat quality traits present significant differences among Bamaxiang, Erhualian and Laiwu breeds. While Erhualian pigs outperformed pH traits, the Laiwu pigs showed extremely high intramuscular fat content, better meat color and lower drip loss (P < .05). The highest contents of total saturated fatty acids and total polyunsaturated fatty acids were found in Laiwu and Erhualian, respectively. These results will benefit the future breeding utilization of these genetic resources for worldwide swine meat quality improvement.

Molecular characterization of an inhibitor of apoptosis protein (IAPs) in freshwater pearl mussel, Hyriopsis schlegelii.

The inhibitor of apoptosis proteins (IAPs) played important roles in inhibiting the apoptosis of tumor cells by regulating caspase activity in mammals. In this study, we first cloned the full-length cDNA sequence of IAPs gene (designated as Hs-IAPs) in Hyriopsis schlegelii. The Hs-IAPs gene contained an open reading frame of 1719 nucleotides, encoding a predicted protein of 572 amino acids. qRT-PCR assay indicated that the Hs-IAPs gene was ubiquitously expressed in different tissues, and the highest expression level was in gills. Furthermore, we purified and obtained the recombinant protein of Hs-IAPs which showed a molecular weight of 82.5 kDa. We used H2O2 stimulation experiment to explore the possible function of Hs-IAPs. The results showed that the percentage of viable cells significantly increased following the Hs-IAPs concentration. These indicated that the Hs-IAPs may play a role in anti-oxidation causing by H2O2, and its anti-oxidative may be crucial in the process of apoptosis.

Chemical Composition and Antimicrobial Activity of Essential Oil from Phytolacca dodecandra Collected in Ethiopia.

The essential oil from Phytolacca dodecandra, a traditional herb of Ethiopia, has been studied, including the chemical composition and antimicrobial activity. The difference between four P. dodecandra samples (P-1⁻P-4), which differed in gender or location, has also been analyzed. The essential oils were obtained by steam distillation, while the aromas were extracted by head space solid-phase microextraction (HS-SPME) and both were analyzed by gas chromatography- mass spectrometry (GC-MS). The oils' antimicrobial activities were evaluated by the microdilution method against Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Candida albicans. Ninety one components, representing 88.37 to 94.01% of the aromas, were identified. The compositions of the aromas of four samples are mainly dominated by aldehydes and ketones: 2-nonanone (1.80⁻30.80%), benzaldehyde (4.99⁻25.99%), and sulcatone (2.34⁻5.87%). Sixty components representing 64.61 to 69.64% of the oils were identified, and phytone (3.04⁻21.23%), phytol (4.11⁻26.29%) and palmitic acid (1.49⁻23.87%) are the major compounds. No obvious antimicrobial activity was observed for all the four essential oils.

Long-term groundwater storage variations estimated in the Songhua River Basin by using GRACE products, land surface models, and in-situ observations.

Influences of climatic change and anthropogenic activities on the terrestrial water storage (TWS) change are significant in the mid- and high-latitude areas. Since 2002, the Gravity Recovery and Climate Experiment (GRACE) satellite mission has provided quantitative measurements of TWS changes with unprecedented accuracy at global, regional and basin scales. In this study, the noise level of various GRACE-derived TWS anomalies (TWSA) data were evaluated by using a generalized three-cornered hat (GTCH) method. A time-dependent weights approach was adopted to obtain a combined TWSA series over the Songhua River Basin (SRB) from 2003 to 2013. Monthly TWSA data during the past decades (1982-2002) were reconstructed by using an artificial neural network (ANN) approach with the good performance evaluated by the correlation coefficient of 0.89 and the Nash-Sutcliff efficiency of 0.79 over the study region. In-situ groundwater level measurements were used for validation of the groundwater storage (GWS) changes (estimated by using GRACE-derived TWS changes in association with the other simulated components of water storage changes from land surface models (LSMs)). The primary driving factors of spatiotemporal variations of GWS, as well as their inter-/intra-annually varying characteristics, were explored. The present study revealed that the variations of GWS featured a "downward fluctuations" (1982-1994), "stable upward" (1998-2008) and "decreasing dramatically" (2009-2013) period, respectively, over the SRB. In general, GWS had varied in a steady decline trend at a decreasing rate of 1.04 ±â€¯0.59 mm year-1 from 1982 to 1994. With the enhanced climatic and anthropogenic influences over the region since 2000, several severe fluctuations characterized the GWS variations with occurrences of spring droughts and flooding over the region, which suggested significant effects of global changes posed on GWS variations of the region.

Genetic correlation of fatty acid composition with growth, carcass, fat deposition and meat quality traits based on GWAS data in six pig populations.

This study investigated genetic correlations of longissimus muscle fatty acid composition with 32 traits related to growth, carcass, fat deposition and meat quality in 2448 pigs from six populations using genome wide SNP data. Most of significant loci for saturated (C14:0, C16:0 and C18:0) and mono-saturated fatty acids (C18:1n9 and C16:1n7) identified in GWAS, including those near ELOVL6, SCD and FASN genes, displayed negligible or weak effects on all the 32 traits. Fat deposition traits were the most relevant traits for fatty acid composition in genetic correlations. Backfat thickness and intramuscular fat content consistently showed strong negative genetic correlations with C18:2n6, and positive genetic correlations with C18:1n9 at least five populations. Intramuscular fat content consistently has positive correlations with saturated fatty acids (SFA) in six populations. This study provided insights into shared genetic control of fatty acid composition and the other economic traits, which is helpful in design of breeding strategies to genetically improve fatty acid composition in pork.

Spatial distribution pattern of degree-day factors of glaciers on the Qinghai-Tibetan Plateau.

Glaciers have a very obvious feedback effect on the global water cycle and environmental change. The Qinghai-Tibetan Plateau, also known as the "Water Towers of Asia," provides an important source of freshwater resources derived from glacial meltwater. Changes in glaciers on the Qinghai-Tibetan Plateau are the most important aspect of the research related to global climate change. Because only a few input parameters are available, the degree-day factor model of glacier mass balance has been widely used on the Qinghai-Tibetan Plateau. Study of the spatial distribution pattern of degree-day factors for glaciers on the Qinghai-Tibetan Plateau and the factors that influence glaciers is important scientifically. The study of degree-day factors is important to the calculation of the glacial grid mass balance on the Qinghai-Tibetan Plateau, and this data can be used in the analysis of the response of glaciers experiencing climate change and for predicting future glacial trends. Through an analysis of the degree-day factors related to 24 glaciers on the Qinghai-Tibetan Plateau, one can conclude that the mean value of glacial degree-day factors on the Qinghai-Tibetan Plateau is 8.14 mm day-1 °C-1. The glacial degree-day factor shows a longitudinal zonality with values ranging from high to low from east to west, a latitudinal zonality with values ranging from high to low from south to north, and a vertical zonal regularity along with the change of elevation. The spatial distribution pattern of glacial degree-day factors in the Tibetan Plateau is related to the fact that the climate environment across the Qinghai-Tibetan Plateau is mainly affected by the Indian monsoon, the eastern monsoon, and the westerly winds. The climate gradually changes from cold-humid to warm-humid from northwest to southeast. The single-unit glacier of Qinghai-Tibetan Plateau-the Renlongba Glacier-is located in the southeastern portion of the Qinghai-Tibetan Plateau in a warm and humid climate; its degree-day factor is slightly large, averaging at 6.12 mm day-1 °C-1. Mountainous barriers exist in the eastern and western parts of the Renlongba Glacier. On the east side, the degree-day factor is small (5.63 mm day-1 °C-1) because of large mountains block weather systems. The glacial tongue is affected by valley wind, contributing to glacial ablation, so the degree-day factor is large on the tongue, averaging at 6.56 mm day-1 °C-1. The degree-day factor on the west side of the Renlongba Glacier increases gradually increasing radiation and elevation, presenting a vertical zonal feature. In general, the climate of the Qinghai-Tibetan Plateau is mainly affected by the Indian and eastern monsoons and by westerly winds. In dry and cold climatic conditions, the glacial degree-day factor in the Tibetan Plateau is small, while at warm and humid climate conditions, it is large, with latitudinal, longitudinal, and vertical zonality. In addition, the degree-day factor is also affected by blocking, topography, and other local microclimatic conditions.

Spatiotemporal distribution and the characteristics of the air temperature of a river source region of the Qinghai-Tibet Plateau.

As the backland of the Qinghai-Tibet Plateau, the river source region is highly sensitive to changes in global climate. Air temperature estimation using remote sensing satellite provides a new way of conducting studies in the field of climate change study. A geographically weighted regression model was applied to estimate synchronic air temperature from 2001 to 2015 using Moderate-Resolution Imaging Spectroradiometry (MODIS) data. The results were R2 = 0.913 and RMSE = 2.47 °C, which confirmed the feasibility of the estimation. The spatial distribution and variation characteristics of the average annual and seasonal air temperature were analyzed. The findings are as follows: (1) the distribution of average annual air temperature has significant terrain characteristics. The reduction in average annual air temperature along the elevation of the region is 0.19 °C/km, whereas the reduction in the average annual air temperature along the latitude is 0.04 °C/degree. (2) The average annual air temperature increase in the region is 0.37 °C/decade. The average air temperature increase could be arranged in the following decreasing order: Yangtze River Basin > Mekong River Basin > Nujiang River Basin > Yarlung Zangbo River Basin > Yellow River Basin. The fastest, namely, Yangtze River Basin, is 0.47 °C/decade. (3) The average air temperature rise in spring, summer, and winter generally increases with higher altitude. The average annual air temperature in different types of lands following a decreasing order is as follows: wetland > construction land > bare land glacier > shrub grassland > arable land > forest land > water body and that of the fastest one, wetland, is 0.13 °C/year.

Genome-wide association studies for fatty acid metabolic traits in five divergent pig populations.

Fatty acid composition profiles are important indicators of meat quality and tasting flavor. Metabolic indices of fatty acids are more authentic to reflect meat nutrition and public acceptance. To investigate the genetic mechanism of fatty acid metabolic indices in pork, we conducted genome-wide association studies (GWAS) for 33 fatty acid metabolic traits in five pig populations. We identified a total of 865 single nucleotide polymorphisms (SNPs), corresponding to 11 genome-wide significant loci on nine chromosomes and 12 suggestive loci on nine chromosomes. Our findings not only confirmed seven previously reported QTL with stronger association strength, but also revealed four novel population-specific loci, showing that investigations on intermediate phenotypes like the metabolic traits of fatty acids can increase the statistical power of GWAS for end-point phenotypes. We proposed a list of candidate genes at the identified loci, including three novel genes (FADS2, SREBF1 and PLA2G7). Further, we constructed the functional networks involving these candidate genes and deduced the potential fatty acid metabolic pathway. These findings advance our understanding of the genetic basis of fatty acid composition in pigs. The results from European hybrid commercial pigs can be immediately transited into breeding practice for beneficial fatty acid composition.

Genetic architecture of fatty acid composition in the longissimus dorsi muscle revealed by genome-wide association studies on diverse pig populations.

BACKGROUND: Fatty acid composition in muscle is an important factor that affects the nutritive value and taste of pork. To investigate the genetic architecture of fatty acid composition of pork, we measured fatty acid contents in longissimus dorsi muscle of 1244 pigs from three divergent populations and conducted genome-wide association studies (GWAS) for fatty acid contents. RESULTS: We detected 26 genome-wide significant quantitative trait loci (QTL) on eight chromosomes (SSC for Sus scrofa) for eight fatty acids. These loci not only replicated previously reported QTL for C18:0 on SSC14 and C20:0 on SSC16, but also included several novel QTL such as those for C20:1 on SSC7, C14:0 on SSC9, and C14:0, C16:0 and C16:1 on SSC12. Furthermore, we performed a meta-analysis of GWAS on five populations, including the three populations that were investigated in this study and two additional populations that we had previously examined. This enhanced the strength of the associations detected between fatty acid composition and several marker loci, especially for those for C18:0 on SSC14 and C20:0 on SSC16. The genes ELOVL5, ELOVL6, ELOVL7, FASN, SCD and THRSP, which have functions that are directly relevant to fatty acid metabolism, are proximal to the top associated markers at six significant QTL. CONCLUSIONS: The findings improve our understanding of the genetic architecture of fatty acid composition in pork and contribute to further fine-map and characterize genes that influence fatty acid composition.

Genome-Wide Association Analysis for Blood Lipid Traits Measured in Three Pig Populations Reveals a Substantial Level of Genetic Heterogeneity.

Serum lipids are associated with myocardial infarction and cardiovascular disease in humans. Here we dissected the genetic architecture of blood lipid traits by applying genome-wide association studies (GWAS) in 1,256 pigs from Laiwu, Erhualian and Duroc × (Landrace × Yorkshire) populations, and a meta-analysis of GWAS in more than 2,400 pigs from five diverse populations. A total of 22 genomic loci surpassing the suggestive significance level were detected on 11 pig chromosomes (SSC) for six blood lipid traits. Meta-analysis of GWAS identified 5 novel loci associated with blood lipid traits. Comparison of GWAS loci across the tested populations revealed a substantial level of genetic heterogeneity for porcine blood lipid levels. We further evaluated the causality of nine polymorphisms nearby or within the APOB gene on SSC3 for serum LDL-C and TC levels. Of the 9 polymorphisms, an indel showed the most significant association with LDL-C and TC in Laiwu pigs. But the significant association was not identified in the White Duroc × Erhualian F2 resource population, in which the QTL for LDL-C and TC was also detected on SSC3. This indicates that population-specific signals may exist for the SSC3 QTL. Further investigations are warranted to validate this assumption.

Assessment of water quality and identification of polluted risky regions based on field observations & GIS in the Honghe River watershed, China.

Water quality assessment at the watershed scale requires not only an investigation of water pollution and the recognition of main pollution factors, but also the identification of polluted risky regions resulted in polluted surrounding river sections. To realize this objective, we collected water samplings from 67 sampling sites in the Honghe River watershed of China with Grid GIS method to analyze six parameters including dissolved oxygen (DO), ammonia nitrogen (NH3-N), nitrate nitrogen (NO3-N), nitrite nitrogen (NO2-N), total nitrogen (TN) and total phosphorus (TP). Single factor pollution index and comprehensive pollution index were adopted to explore main water pollutants and evaluate water quality pollution level. Based on two evaluate methods, Geo-statistical analysis and Geographical Information System (GIS) were used to visualize the spatial pollution characteristics and identifying potential polluted risky regions. The results indicated that the general water quality in the watershed has been exposed to various pollutants, in which TP, NO2-N and TN were the main pollutants and seriously exceeded the standard of Category III. The zones of TP, TN, DO, NO2-N and NH3-N pollution covered 99.07%, 62.22%, 59.72%, 37.34% and 13.82% of the watershed respectively, and they were from medium to serious polluted. 83.27% of the watershed in total was polluted by comprehensive pollutants. These conclusions may provide useful and effective information for watershed water pollution control and management.