Quality Constituents Research Articles

Effect of papaya (Carica papaya) seed as phytogenic feed additives on egg performance, egg quality and blood serum biochemical constituents of layer hens.

Supplementing poultry diets with certain natural phytogenic additives has positive impacts on performance parameters like feed intake, egg production and quality of layer hens. The study aimed to examine how supplementing papaya seed as phytogenic feed additive (PFA) to the diets of layer chickens affected their egg production, quality and blood serum biochemical parameters. One hundred twenty 28-week-old Bovans brown laying hens were randomly assigned to one of four treatments with varying levels of papaya seed supplementation at 0g/kg (T1), 5g/kg (T2), 10g/kg (T3) and 15g/kg (T4) in a complete randomized design. Layer chickens supplemented with 0.5% (T2), 1% (T3) and 1.5% (T4) papaya seed as a PFA had significantly (p<0.05) improved dry matter intake, egg production%, egg mass and feed conversion. On the other hand, papaya seed supplementation decreased (p<0.05) the bodyweight gain of laying hens. Papaya seed supplementation significantly (p<0.05) increased egg weight, length, width, yolk height and yolk colour compared to the control group. Serum total protein on T4 and liver enzyme of alkaline phosphatase on T3 were significantly greater (p<0.05) than in the control group. However, there were no significant differences (p>0.05) in serum albumin, glucose, total cholesterol, triglyceride and aspartate aminotransferase levels among treatments laying hens. Papaya seed can be a potential candidate as a PFA at 5-15g/kg of the basal diet to improve egg-laying performance and quality without deteriorating effect.

On the biodiversity of diatom communities in lakes of East China: Geochemical effects dominated after eutrophication

AbstractAimOver the last century, lakes all over the world have experienced significant eutrophication and become more susceptible to critical transitions. This has prompted a growing need to understand how community dynamics shift following ecological perturbations. This study aims to elucidate the present status, spatial patterns and determinants of biological diversity, and how they have changed in response to alterations driven by eutrophication.LocationLakes of East China, mostly in the Yangtze River Basin.TaxaBacillariophyceae (163 species in 33 genres, see taxa names in Appendix S1).MethodsThe environmental conditions of over 60 lakes were assessed based on parameters such as water quality, physical characteristics and biogeochemical constituents. Surface sediment samples and high‐resolution sediment records were collected to quantify the biodiversity of diatom communities, and principal component analysis (PCA) was used to determine the major environmental gradients. Meanwhile, linear regression, canonical correlation analysis and Mantel tests were used to quantify the correlations between variables.ResultsBiodiversity metrics showed no distinct geographic patterns, although areas near large lakes showed comparatively high evenness. Smaller pairwise dissimilarities were observed among hypereutrophic lakes in comparison to lakes with a lower trophic status. The past century has witnessed a decrease in both pairwise dissimilarity and the standard deviation of evenness. A significant statistical association was found between dissimilarity and ionic concentration and composition in the surface sediment of lakes, rather than nutrient levels.Main ConclusionsFollowing regional eutrophication and human disturbance, a significant reduction in biodiversity differentiation was observed in lakes located in East China. Currently, the dominant factor in determining the beta diversity of diatom communities is geochemical conditions rather than nutrient concentrations. Long‐term stress caused by cultural eutrophication may also have altered the dominant determinant of regional biodiversity and diatom community dynamics.

HARP: A suite of parameters to describe the hysteresis of streamflow and water quality constituents

Hysteresis occurs in ecological systems when there are internal dynamics that produce variable responses to an external stimuli or stressors. Understanding and quantifying hysteresis is important to inform understanding of system behaviour, support modelling, and provide comparisons within and between systems. We introduce a new tool, HARP (Hysteresis Area, Residual and Peaks) to describe and quantify hysteresis. HARP quantifies the key features of stream discharge–constituent concentration relationships, including the magnitude of the hysteresis (deviation from linearity), phase shifts in the system (end-state deviation from the pre-event state), and the timing of the turning points in the relationship of discharge and concentration. HARP is suitable to use on complex discharge–concentration data, including figure-eight loops, and supports statistical analysis to quantify the characteristics of independent events. The HARP metrics are introduced using discharge–water quality constituent concentration data, but are equally applicable to any system with properties of hysteresis. HARP provides a tool to develop quantitative observations of stream hydrological processes into quantitative enumeration statistics that facilitate comparisons of events and streams.

Effect of lactic acid fermentation on the quality and phytochemical constituent in smoothies made from the leaves of different sweet potato (Ipomoea batatas L.) cultivars

SummaryThis study investigated the effect of fermentation by Lactiplantibacillus plantarum 75 (L75) on the physicochemical properties, survival of L75, sensory, antioxidants and their activities in leaf smoothies of six sweet potato cultivars [Orange‐fleshed (OFSP): ‘Bophelo’, and ‘Beauregard’; cream‐fleshed (CFSP): ‘Blesbok’ and ‘Ndou’; and purple‐fleshed (PFSP): ‘08.21p’ and ‘Purple‐purple’]. Fermentation significantly affected the physiochemical properties. Fermentation for 24 h improved the carotenoid (TCC), ascorbic acid (AA) (6.8, 6.0 mg 100 g−1) and total phenolic (4435 mg 100 g−1) significantly in, ‘Bophelo’ smoothies. Whilst 48 h fermentation significantly increased the TCC, AA, organic acids, valine and alanine levels in ‘Blesbok’ smoothies'. Principal component analysis separated the unfermented ‘Bophelo’ and Purple‐purple’ leaf smoothies from fermented leaf smoothies of OFSP, CSFP, and PFSP. DPPH scavenging activity and alpha‐carotene were effective markers for separating fermented from unfermented leaf smoothies in the variable importance study. Survival of L75 was influenced by fermentation duration and cultivar type. Fermented and unfermented smoothies were equally acceptable.

A complex interplay among agricultural land uses, urbanization, and landscape attributes shapes the concentration-discharge relationships in Ontario, Canada

The shape of a concentration-discharge (C-Q) relationship and its evolution in space and time can be used to elucidate the predominant hydrological pathways and residence time of a chemical of interest, to determine the rate and timing of biogeochemical production and uptake, and to evaluate how catchment characteristics (topography, land cover/soil vegetation, anthropogenic activities) modulate export dynamics. Being a powerful tool to address ecohydrology’s fundamental questions, the investigation of C–Q relationships for multiple elements at multiple spatial and temporal scales has been instrumental in the context of water-quality management. In this study, we use a statistical (Segmented, Classification and Regression Trees) modelling framework to establish linkages among watershed morphological attributes, weather variability, land-use patterns, and biogeochemical “hot spots” across Ontario, Canada. Our analysis signifies the presence of enriching behavior, either across the entire streamflow domain or at high flow regimes, for several water quality constituents, such as total phosphorus, suspended solids, nitrate, calcium, and dissolved organic carbon. Alkalinity, calcium, and dissolved inorganic carbon consistently displayed negative slopes at higher flows, indicative of source limitation for these constituents. Similarly, although many of our study watersheds are influenced by anthropogenic activities, the predominant C-Q relationship for chloride was suggestive of either a monotonically diluting pattern or a diluting one followed by a chemostatic response to increasing streamflows. Our results offer novel insights into the interplay between anthropogenic stressors and biogeochemical processes that shapes the severity of nonpoint-source pollution, as hydrological and nutrient cycles will be increasingly subjected to major disturbances by food-production systems and urbanization.

Impact of a natural disturbance on the performance and microbial communities in a full-scale constructed wetland for industrial wastewater treatment

Constructed Wetlands (CWs) are a cost-effective, versatile and sustainable choice for wastewater treatment. In these environments, microbial communities play a significant role in pollutant removal. However, little is known about how microbial communities in full-scale CWs contribute to maintaining water quality or how their dynamics change in response to pulse disturbances such as fire or freezes. Furthermore, few studies have examined the relationship between CW microbial community structure and performance in full-scale industrial operations. We characterized the water-column and leaf-litter layer microbial communities in a 110-acre free water surface CW that provides tertiary wastewater treatment to a plastics manufacturing plant. The CW’s sampling campaign was conducted over a 12-month period that included Winter Storm Uri, a 100-year freeze event. Analysis of 16S rRNA gene amplicon sequences revealed that the bacterial communities experienced a temporal shift. There was also a shift in microbial community structure between the influent and the first segment of the CW. However, no differences in microbial community structure were observed in the second segment of the CW. There was a negative association between microbial community diversity and chlorophyll a, as well as microbial community diversity and total suspended solids (TSS); demonstrating an increase in microbial biodiversity as water quality improved throughout the CW. Six months after the freeze, CW performance in terms of removal of water quality constituents began to return to former removal trends. Yet, there was still a significant difference in microbial community structure within the CW relative to the previous year. This suggests CW functional resilience despite a shift in microbial community structure in the wetland.

Improving detention ponds for effective stormwater management and water quality enhancement under future climate change: a simulation study using the PCSWMM model

Urban surfaces are often covered by impermeable materials such as concrete and asphalt which intensify urban runoff and pollutant concentration during storm events, and lead to the deterioration of the quality of surrounding water bodies. Detention ponds are used in urban stormwater management, providing two-fold benefits: flood risk reduction and pollution load minimization. This paper investigates the performance of nine proposed detention ponds (across the city of Renton, Washington, USA) under different climate change scenarios. First, a statistical model was developed to estimate the pollutant load for the current and future periods and to understand the effects of increased rainfall on stormwater runoff and pollutant loads. The Personal Computer Storm Water Management Model (PCSWMM) platform is employed to calibrate an urban drainage model for quantifying stormwater runoff and corresponding pollutant loads. The calibrated model was used to investigate the performance of the proposed nine (9) detention ponds under future climate scenarios of 100-year design storms, leading to identifying if they are likely to reduce stormwater discharge and pollutant loads. Results indicated significant increases in stormwater pollutants due to increases in rainfall from 2023 to 2050 compared to the historical period 2000–2014. We found that the performance of the proposed detention ponds in reducing stormwater pollutants varied depending on the size and location of the detention ponds. Simulations for the future indicated that the selected detention ponds are likely to reduce the concentrations (loads) of different water quality constituents such as ammonia (NH3), nitrogen dioxide (NO2), nitrate (NO3), total phosphate (TP), and suspended solids (SS) ranging from 18 to 86%, 35–70%, 36–65%, 26–91%, and 34–81%, respectively. The study concluded that detention ponds can be used as a reliable solution for reducing stormwater flows and pollutant loads under a warmer future climate and an effective adaptation option to combat climate change related challenges in urban stormwater management.

Advances in Catchment Science, Hydrochemistry, and Aquatic Ecology Enabled by High-Frequency Water Quality Measurements.

High-frequency water quality measurements in streams and rivers have expanded in scope and sophistication during the last two decades. Existing technology allows in situ automated measurements of water quality constituents, including both solutes and particulates, at unprecedented frequencies from seconds to subdaily sampling intervals. This detailed chemical information can be combined with measurements of hydrological and biogeochemical processes, bringing new insights into the sources, transport pathways, and transformation processes of solutes and particulates in complex catchments and along the aquatic continuum. Here, we summarize established and emerging high-frequency water quality technologies, outline key high-frequency hydrochemical data sets, and review scientific advances in key focus areas enabled by the rapid development of high-frequency water quality measurements in streams and rivers. Finally, we discuss future directions and challenges for using high-frequency water quality measurements to bridge scientific and management gaps by promoting a holistic understanding of freshwater systems and catchment status, health, and function.

Shelf Life Quality and Bioactive Constituents of Virgin Olive Oil Affected by Packaging Type and Storage Days

Shelf Life Quality and Bioactive Constituents of Virgin Olive Oil Affected by Packaging Type and Storage Days

Pecora 22: Remote Sensing for Freshwater and Marine Environments

Pecora 22: Remote Sensing for Freshwater and Marine Environments

Water Quality Modeling in Headwater Catchments: Comprehensive Data Assessment, Model Development and Simulation of Scenarios

Water quality is a major concern globally and in headwater catchments of developing countries it is often poorly managed. In these catchments, having scarce and heterogeneous information hinders the development of water quality assessments and predictive models to support management. To address this issue, the authors propose a framework of three stages that allows for: (i) conducting a comprehensive assessment of water quality; (ii) the development of a mountain stream water quality model based on said assessment; and (iii) the simulation of scenarios with the model to resolve conflicts between uses and quality of water. The framework involves multivariate analyses of principal components and clusters and follows a novel modeling protocol mainly designed for mountainous streams in developing countries. Applied to an Andean catchment in Colombia, the first stage of the framework revealed the catchment’s most significant water quality constituents and the most polluted season. The problematic constituents in this catchment include pathogens, nutrients, organic matter, and metals such as the highly toxic Cr and Pb, while water pollution is the highest during the driest months of the year (i.e., January to March). In the second stage, the model was calibrated reproducing the concentrations of pathogens, organic matter, and most nutrients, and showed a predictive capacity. This capacity was measured with an objective function to be minimized based on a normalized root mean square error. It increased only 14% when verified with a different dataset. In addition, during the third stage of the proposed framework, the simulation of alternative scenarios showed that centralized treatment is not sufficient to make water safe for potabilization and agriculture in the catchment. For this reason, improving water quality in the sub-basins at the highest altitudes is required. The proposed framework can be applied in other headwater catchments where information is limited, and where an improved management of water quality is needed.

A Machine Learning Approach to Predict Watershed Health Indices for Sediments and Nutrients at Ungauged Basins.

Effective water quality management and reliable environmental modeling depend on the availability, size, and quality of water quality (WQ) data. Observed stream water quality data are usuallEEy sparse in both time and space. Reconstruction of water quality time series using surrogate variables such as streamflow have been used to evaluate risk metrics such as reliability, resilience, vulnerability, and watershed health (WH) but only at gauged locations. Estimating these indices for ungauged watersheds has not been attempted because of the high-dimensional nature of the potential predictor space. In this study, machine learning (ML) models, namely random forest regression, AdaBoost, gradient boosting machines, and Bayesian ridge regression (along with an ensemble model), were evaluated to predict watershed health and other risk metrics at ungauged hydrologic unit code 10 (HUC-10) basins using watershed attributes, long-term climate data, soil data, land use and land cover data, fertilizer sales data, and geographic information as predictor variables. These ML models were tested over the Upper Mississippi River Basin, the Ohio River Basin, and the Maumee River Basin for water quality constituents such as suspended sediment concentration, nitrogen, and phosphorus. Random forest, AdaBoost, and gradient boosting regressors typically showed a coefficient of determination for suspended sediment concentration and nitrogen during the testing stage, while the ensemble model exhibited . Watershed health values with respect to suspended sediments and nitrogen predicted by all ML models including the ensemble model were lower for areas with larger agricultural land use, moderate for areas with predominant urban land use, and higher for forested areas; the trained ML models adequately predicted WH in ungauged basins. However, low WH values (with respect to phosphorus) were predicted at some basins in the Upper Mississippi River Basin that had dominant forest land use. Results suggest that the proposed ML models provide robust estimates at ungauged locations when sufficient training data are available for a WQ constituent. ML models may be used as quick screening tools by decision makers and water quality monitoring agencies for identifying critical source areas or hotspots with respect to different water quality constituents, even for ungauged watersheds.

Evaluation of the Export of Fecal Contamination from Roadside Green Infrastructure

Fecal contamination in stormwater runoff is a leading contributor of waterbody impairment in the US, and green infrastructure (GI) has demonstrated variable performance in its mitigation. Therefore, there is a need for studies that use robust sampling methods to quantify concentration and load reductions as well as evaluate export of fecal contamination with respect to other water quality constituents. The objective of this study was to characterize the performance of various types of GI systems in mitigating fecal contamination [measured as Escherichia coli (EC)] in highway stormwater runoff. This study was conducted at a field site on Lorton Road in Fairfax County, Virginia, where a bioretention, bioswale, compost-amended grass channel and a grass channel were instrumented for 2 years in all seasons for flow-weighted composite sampling and volume monitoring. The bioretention effectively reduced EC concentration and loading from a relatively high inflow concentration [1,120 most probable number (MPN)/100 mL]. The swales, however, consistently increased EC concentration from their relatively low average inflow concentration of 58 MPN/100 mL but had no significant impact on mass load. For all GI systems, outflow concentrations were regularly above recreational water quality standards. Regression analyses indicated that average daily temperature, dissolved organic carbon, total dissolved nitrogen, and chloride were significantly correlated with the log-transformed EC concentrations exiting the GI systems. We conclude that EC export is prevalent in varying degrees in the studied GI systems such that the bioretention reduces its presence, whereas the swales often increase its presence. This study provides insight into environmental factors and common stormwater quality constituents that are correlated with the export of fecal contamination from GI.

Influence of Organic Iron Enriched Diets on Performance, Egg Quality, Blood Haematological and Biochemical Constituents in Quails

The current research was carried out to investigate the effect of diets enriched with different levels of organic iron on performance, egg quality, blood haematological parameters, and serum biochemical constituents in laying quails. In the study, 120 female quails at 20 weeks of age were allocated to 5 treatment groups with 6 replicates of 4 quails in each. Experimental diets were formed by adding 0, 50, 100, 150, and 200 mg/kg of iron (iron-glycine) to the diet containing 96 mg/kg of iron. Performance parameters of quails were not affected by the supplementation of organic iron to diet (P&gt;0.05). The supplementation of organic iron affected as quadratic only the eggshell breaking strength among the egg external quality parameters, and it was maximum at 150 mg/kg organic iron addition (P&lt;0.01). Egg yolk a* value, which is one of the egg internal quality parameters, was linearly affected by organic iron addition, but other parameters were not affected (P&lt;0.01). The administration of organic iron to the diet linearly increased the serum iron level (P&lt;0.01), the serum phosphorus level was affected quadratically (P&lt;0.05) and reached a maximum at 150 mg/kg. Among the blood haematology parameters, white blood cell and monocyte counts linearly increased with the addition of organic iron to the diet (P&lt;0.01), but other parameters were not affected. According to the results obtained from current research, it can be said that enrichment of laying quail diets with organic iron up to 150 mg/kg level improved eggshell breaking strength without affecting performance, however, it negatively affected blood parameters by increasing white blood cell and monocyte without changing blood red cell parameters.

Comparison of Two Water Color Algorithms: Implications for the Remote Sensing of Water Bodies with Moderate to High CDOM or Chlorophyll Levels.

The dominant wavelength and hue angle can be used to quantify the color of lake water. Understanding the water color is important because the color relates to the water quality and its related public perceptions. In this paper, we compared the accuracy levels of two methods in calculating dominant wavelength and hue angle values using simulated satellite data calculated from in situ reflectance hyperspectra for 325 lakes and rivers in Minnesota and Wisconsin. The methods developed by van der Woerd and Wernand in 2015 and Wang et al. in 2015 were applied to simulated sensor data from the Sentinel-2, Sentinel-3, and Landsat 8 satellites. Both methods performed comparably when a correction algorithm could be applied, but the correction method did not work well for the Wang method at hue angles < 75°, equivalent to levels of colored dissolved organic matter (CDOM, a440) > ~2 m-1 or chlorophyll > ~10 mg m-3. The Sentinel-3 spectral bands produced the most accurate results for the van der Woerd and Wernand method, while the Landsat 8 sensor produced the most accurate values for the Wang method. The distinct differences in the shapes of the reflectance hyperspectra were related to the dominant optical water quality constituents in the water bodies, and relationships were found between the dominant wavelength and four water quality parameters, namely the Secchi depth, CDOM, chlorophyll, and Forel-Ule color index.

A data-driven approach to flag land-affected signals in satellite derived water quality from small lakes

The land-affected signal in remotely sensed radiance from nearshore waters is a common problem for remote sensing, introducing uncertainty in atmospheric correction and subsequent water quality constituent concentration estimates. This study proposes a new method for identifying effects of land on satellite remote sensing of water quality. The new optical water types (OWT) containing the land-affected signal were derived from POLYMER-corrected imagery of the Medium Resolution Imaging Spectrometer in reduced resolution (MERIS RR) and Sentinel-3 Ocean and Land Colour Instrument (OLCI). These were then applied, as part of a larger set of existing OWTs corresponding to the variability observed in natural waters, to satellite images. The ability to identify pixels containing both water and land, and those contaminated with radiance from adjacent land, was evaluated. Our test sites include dark lakes of varying size in Sweden (Lakes Rusken, Bolmen, Ringsjön, and Ivösjön) where the classification showed high sensitivity to land near the lake shore. The land-affected signal is shown to lead to underestimations of chlorophyll-a concentration and Forel-Ule colour indices, and overestimations of turbidity in these lakes, which can be corrected after masking out the land-affected pixels. The land-affected signal is strongest in summer, both NDVI and sun zenith angle covaried with the seasonal variation of land-affected signal. Further, the results confirmed that satellite images with coarser spatial resolution are more prone to land-affected signal compared to images with finer spatial resolution, for small inland water bodies. We propose a data-driven approach for water quality processing with ‘land-affected water types’ as an effective way to improve the lake optical water quality monitoring from water colour sensors.

Fruit quality and volatile constituents of a new very early-ripening pummelo (Citrus maxima) cultivar 'Liuyuezao'.

'Liuyuezao' (LYZ) pummelo (Citrus maxima) originated from a spontaneous bud sport on a 'Guanxi' (GXB) pummelo tree and was released as a new very early-season cultivar. The objective of this study was to present the sensory and nutritional profiles of LYZ fruits, and compare it with other major commercialized pummelo cultivars including GXB, 'Sanhong' (SH) and 'Hongrou' (HR). LYZ had higher contents of organic acids (12.01 mg/g), phenols (669.01 mg/L), vitamin C (75.73 mg/100 mL) and stronger antioxidant capacity (77.65 mg/100 mL) but lower levels of soluble sugars (62.85 mg/g), carotenoids (0.25 mg/L) and flavonoids (46.3 mg/L) when compared to the other pummelos. Moreover, a smaller number (49) and much less content (7.63) of fruit volatiles were detected in LYZ than them in GXB, SH and HR. The relatively high levels of fructose (20.6 mg/g) and organic acids and low levels of volatile compounds in LYZ mainly contributed to its sweet and mildly sour taste and moderate aroma of pummelo note. LYZ is presented as an alternative pummelo cultivar with the potential for commercialization.

Green tea processing by pan-firing from region-specific tea (Camellia sinensis L.) cultivars - a novel approach to sustainable tea production in Dooars region of North Bengal

The black crush-tear-curl (CTC) tea constitutes the bulk tea production in Dooars region of North Bengal while green tea processing is confined to fewer tea estates, however, recent trends of the tea industry indicate gradual inclination towards green tea production. Our novel research findings on pan-fired green teas from twelve cultivated region-specific tea varieties at three flushes and data analysis of chemical and sensory quality attributes showed diversity in the leaf chlorophyll and carotenoid contents, as well as wide ranges of variation in green tea quality constituents including Polyphenols, Total Catechins, Catechin fractions, caffeine, free amino acids, Polyphenol to Amino acids ratio, Soluble Solid content and tasters’ quality scores. Most parameters differed significantly among the tea cultivars and between the three flushes within a certain cultivar. This study has highlighted the role of genetic variability of tea cultivars, processing conditions, and seasonal influence in determining green tea quality.

친환경 수처리 기술을 이용한 하천 및 원수 수질 개선 연구

In this study, the use of an infiltration constructed wetland (ICW) as an eco-friendly water treatment technology for improving the quality of raw water and river water was evaluated using a full-scale test-bed built in the upper reaches of the old Seung-chon weir river channel. The average removal efficiency for the biochemical oxygen demand, suspended solids, and total phosphorus over three years was 86.8%, 96.6%, and 83.1%, respectively. However, the removal efficiency for total organic carbon and total nitrogen was relatively low, which is thought to be due to the characteristics of the influent. The general water quality constituents (BOD, SS, T-N and T-P) were not significantly different in winter when the water temperature was lower, indicating that stable water treatment over all four seasons was possible. In addition, biopolymers, humic substances, and building blocks of influent (Yeongsanriver) were able to be removed, illustrating that ICWs can be used as an effective eco-friendly water treatment technology to improve the quality of raw and river water. The removal efficiency for heavy metals, pesticides, and pharmaceuticals varied greatly, suggesting that further research is required to identify the main factors that affect there moval efficiency of ICWs.

Groundwater Quality and Potential Pollution in the Southern Shimabara Peninsula, Japan

Nitrate pollution in groundwater is a severe problem in Shimabara Peninsula, Nagasaki Prefecture, Japan. Previous studies have investigated water quality characteristics in the northern part of the peninsula and shown serious effects of nitrate pollution in the groundwater. The present study aimed to investigate the groundwater quality in the southern areas of the peninsula for improved understanding of the water quality status for the entire peninsula. Groundwater samples were collected at 56 locations in Minami-Shimabara City from 28 July to 4 August 2021. The spatial distribution of water quality constituents was assessed by Piper-trilinear and Stiff diagrams for major ion concentrations. One agricultural area in the western parts exceeded Japanese recommended standards for water. According to the Piper-trilinear diagram, 44 sampling sites (78.6%) were classified as alkaline earth carbonate type, nine sites (16.1%) as alkaline earth non-carbonate type, and three sites (5.3%) as alkaline carbonate type. Stiff diagrams displayed Ca-HCO3 water type for most of the sites. Na-HCO3 and Mg-HCO3 types were found in coastal areas. Principal component analyses showed that the first component corresponded to dissolved constituents in groundwater and denitrification, the second effects of ion exchange and low nitrate pollution, and the third effects of severe nitrate pollution. Hierarchical cluster analysis was used to classify the groundwater into five groups. The first group included sites with relatively high nitrate concentration. The second group had relatively low ion concentration, distributed from center to eastern parts. The third group included intermediate ion concentration, distributed at lower altitudes along the coastal line. The fourth and fifth groups had a higher ion concentration, especially characterized by high sodium and bicarbonate concentration.