Tracking the sources of metals to the San Juan River, Four Corners Region, USA: an introduction to the thematic collection

Physical and chemical characteristics of sediment influence the transport of metals in rivers. The San Juan River and its tributaries are located in the Four Corners Region in the southwestern United States and the watershed contains a wide variety of potential metal sources. Comparisons of past and present sediment data provide insight on the effects of seasonality and storm events to sediment transport within a watershed. Comparisons suggest finer (<0.63 µm) sediment particles increase at a greater rate during intense storm events than coarser sediment particles. These fine, clay-sized sediments have a greater potential for metal sorption. Statistical analyses compared upper and lower portions of the San Juan River. Results show total elemental concentration decreases in sediments (1,785.15 μ g/L) and that concentrations increase in the aqueous phase (2,063.08 μ g/L) downstream in the San Juan River. Geochemical and scanning electron microscopy with energy dispersive spectroscopy analyses suggest that sediment clay particles are the most likely constituent transporting metals in the San Juan River. Metal transport is further aided by metal oxide coatings developing on the surfaces of larger particles. Increases in aggregation of fine-grained particles in the downstream portions of the San Juan River is also likely to bind elements within sediments which can act as both a source and sink for metals in the lower watershed.

Basin morphometry, climate, and geology control how a hydrologic network evolves over time, controlling the efficiency of weathering of elements from geologic materials, and ultimately the input of sediment and dissolved constituents to river systems. Exceedances to the Navajo Nation surface water-quality standards for trace metals have been reported in the San Juan River watershed. Because metals are transported adsorbed to fine-grain sediment, the identification of areas with elevated sources of trace metals and/or areas with increased erosion and sediment transport potential is an important first step in protecting water quality. Physical factors such as elevation, slope, relief, and stream order were used to quantify morphometric parameters that effect the contribution of trace metals into the stream network. By correlating these parameters with water quality data that were collected from tributaries along the San Juan River, we identified statistically significant regressions between morphometric parameters and total Al, Pb, U, Fe, and Mn in surface water. Positive correlations with trace metals include tributary drainage basin perimeter, pour point elevation, and total number of streams, while negative correlations include stream length ratio, ruggedness number, and longest basin axis. Stream reach measurements within geologic units that contain known trace metal constituents reveal that Gallegos Canyon and Desert Creek are the most susceptible to sediment mobilization and transport, while other tributary drainage basins such as Desert, Recapture, and Salt Creeks are associated with naturally elevated concentrations of Al, As, Pb, and U.

Water is the major limiting factor in agriculture in arid and semi arid regions. The shortage of water resources of good quality is becoming an important issue. The main goal of this study is to analyze the quality of ground and surface water in Eli River Valley and analyze the feasibility of the use of ground and surface water for irrigation in the study area. On the basic of the monitored data of surface and ground water in Eli River Valley in August of 2008, the water quality were evaluated .The results showed that the mean anion concentrations occur in the order SO 4 2- > Cl - and cations in the order Ca 2+ >Na + > Mg 2+ > K + for groundwater while mean anion concentrations occur in the order SO 4 2+ > Cl - and cations in the order Na + > Ca 2+ > Mg 2+ > K + for surface water. The type of groundwater is moderately saline while the type of surface water is slightly saline. Both surface and ground water could be used for irrigation. In the study area, we can solve the problem of water shortage by conjunctive use of ground and surface water.

Assessment of heavy metal contamination levels and health risks in environmental media in the northeast region

The surface water quality issue in arid regions is becoming increasingly severe and has become a significant challenge for global environmental protection and water resource management. By continuously collecting surface water samples (2000~2024) and utilizing hydrochemical and principal component analysis, the changes in the chemical composition of surface water and its water quality pollution characteristics are examined in the Shiyang River Basin. The surface water anion concentrations are characterized by HCO3− > SO42− > Cl−, with average concentrations of 214.11 mg/L, 117.31 mg/L, and 21.61 mg/L, respectively. The cation concentrations follow the trend of Ca2+ > Mg2+ > Na+ > K+, with average concentrations of 56.22 mg/L, 33.75 mg/L, 22.91 mg/L, and 5.33 mg/L, respectively. The dominant water types are Ca-HCO3 and Ca (Mg)-HCO3 in the mountainous area and in the plains, respectively. The weathering of carbonates and silicates is the main controlling factor for the evolution process of surface water. Strong evaporation leads to significant differences in ion concentrations, which is manifested as low in mountainous areas and high in plain areas. In addition, the surface water quality in the plains is worse than that of the mountainous areas. The main pollution indicators include DO, CODMn, COD, BOD5, NH4+-N, TP, TN, and fecal coliforms. The surface water quality of Hongyashan Reservoir and Caiqi has improved significantly, reflecting the impact of the water diversion project. The results of this study are of great significance for improving water resource management and ensuring the sustainability of the ecological environment in arid regions.

Water Resources Perspectives: Evaluation, Management and Policy

The mining of metal resources is one of the major sources of heavy metals in surface water, but studies on the different characteristics of the impact of the exploitation of mineral metal resources on surface water from a large-scale perspective are lacking. In the present study, we quantified the impacts of mineral metal resource development on As, Cu, Cr, Pb, Zn, Hg, Ni, Cd, Mn, and Fe in the overlying water and sediments of surface water under different scenarios (i.e., different geographic units and different mined metal types) using meta-analysis for the Mongolian Plateau of Mongolia and the Inner Mongolia Autonomous Region of China, which is rich in mineral metal resources and has high exploitation and use intensity. Finally, funnel plots and Egger’s regression analysis were used to test the publication bias of the data. The results show that the order of heavy metal content in the overlying water of the Mongolian Plateau was Fe > Mn > As > Zn > Cu > Pb > Cr > Ni > Cd > Hg, and the order of heavy metal content in the sediment was Fe > Mn > Zn > Cr > Pb > Ni > Cu > As > Cd > Hg. In addition, As, Cr, Zn, Hg, Cd, and Pb in overlying water exceeded the standard to different degrees, among which the contents of As and Pb were 1.4 and 1.3 times higher than the World Health Organization guideline, and the contents of Cr, Pb, Hg, Cd were 1.5, 1.3, 25.4, 2.6 times Chinese environmental quality standards for surface water, and the contents of As, Pb, Zn, Hg were 1.4, 1.3, 4.7, 12.7 times Mongolian water quality standards, respectively. The content of As in sediments was 2.6 times the background value of soil environmental quality in Inner Mongolia. Significant differences existed in the content of heavy metal pollutants in surface water of different countries; the content of heavy metals in the overlying water was significantly higher in Inner Mongolia Autonomous Region of China than in Mongolia. Copper and molybdenum polymetallic mines significantly increased the content of Cd, Cr, Cu, Fe, Hg, Pb, and Zn in the overlying water, while the content of As, Cr, Pb, and Zn in overlying water increased significantly due to lead–zinc mining. However, the mining of gold–silver, lead–zinc, copper–molybdenum, and other polymetallic mines all significantly affected the concentration of As in sediments. The results of the present study can provide data support for environmental protection and the restoration of surface water in metal mining areas of the Mongolian Plateau.

The North American Monsoon (NAM) is an important source of precipitation across the southwestern United States. The approximate northern boundary of this feature crosses the Navajo Nation (NN), in the Four Corners region, where NAM rains have long been important to the livelihoods of Native Americans. Relatively little is known about the characteristics and hydrological significance of the NAM in this region. Here, we report a new 4 yr record of stable H and O isotope ratios in monsoon‐season rainfall and water resources across the NN. Monthly precipitation samples collected at 39 sites document a characteristic pattern of 2H‐ and 18O‐enrichment associated with monsoonal precipitation. These changes are weakly correlated with local precipitation amount, however, and the correlation that does exist is dominated by sub‐cloud evaporation effects. In contrast to precipitation amount, monsoon‐season isotopic values exhibited little spatial variability across the region, and after correction for sub‐cloud evaporation NN values were similar to those from a site in southern Arizona. Airmass back trajectory analysis suggests that the uniformly high NAM precipitation water isotope ratios across the region may reflect (a) a region‐wide shift from mid‐latitude to low‐latitude moisture sources at the onset of the peak monsoon, and (b) substantial land‐surface recycling of NAM moisture in upwind regions. Comparison of precipitation water isotope data with surface and groundwater values implies that, despite its hydroclimatic significance, monsoon rainfall contributes little to subsurface water resources. This highlights the monsoon's importance for warm‐season land‐surface ecology and hydrology critical to residents in the Four Corners region.

Chapter 6 - Assessment of COVID-19 lockdown impact on surface water quality using remote sensing techniques in Raipur, Chhattisgarh, India

Canola is a cash crop produced for its highly-valued seed, and as a protein source for animal feed. While winter canola is produced mainly in the high plains, it is expanding to new environments, and is greatly incorporated into crop systems with advantages in terms of increasing crop yield and improving soil health. The objectives of this study were to evaluate eight winter canola genotypes for seed yield, and to determine their water productivity under semiarid climates and high elevations in the Four Corners region at Farmington, New Mexico. A field experiment was conducted at the New Mexico State Agricultural Science Center at Farmington for five growing seasons. Eight genotypes of winter canola (Baldur, Flash, Safran, Sitro, Virginia, Visby, Wichita, and Sumner) were arranged into the randomized complete block design. The field was fully irrigated with a center pivot irrigation system. Results showed that winter canola seed yield was dependent on genotype, varying from 2393 to 5717 kg/ha. The highest yield was achieved by Sitro, and the lowest yield by Sumner. There was inter-annual variation in canola nitrogen-use efficiency (NUE), irrigation water-use efficiency (IWUE), and crop water-use efficiency (CWUE). NUE varied from 12.9 to 50.4 kg seed/kg N, with the highest NUE achieved by Sitro, and the lowest by Sumner. IWUE varied from 0.34 to 0.80 kg/m3, and canola CWUE from 0.28 to 0.69 kg/m3. The highest water productivity was achieved by Sitro. The results of this study showed full assessment of canola production under the semiarid climate in the Four Corners region, and could improve crop productivity and profitability.

The Doi Canal and the Cho Dem and Ben Luc Rivers play the key roles in irrigation, navigation and ecological restoration. It is important to clearly identify the pollution, influencing factors, ecological risks and possible sources of heavy metals in the surface water of this river system. The surface water of 7 sampling sites was collected over 7 consecutive periods from April 2019 to October 2021. Each surface water sample was analyzed for 9 heavy metals including Fe, Mn, Cr, Zn, Cu, Pb, Cd, Ni, As. Sampling and sample handling techniques were performed based on the Standard Methods for the Examination of Water and Wastewater. Among all nine heavy metals examined in the study area, the concentrations of Fe (1.00 ¸ 5.06 mg/L) and Mn (0.14 ¸ 0.28 mg/L) were the highest and the concentrations of Cr, Cd and As were below the lower limit of detection. The results showed that the average Fe and Mn contents both exceeded the permissible thresholds of the National technical regulation on surface water quality (QCVN 08-MT: 2015/BTNMT). Additionally, the content of Fe, Mn, Zn, Cu, Pb, Ni did not meet the water quality standards for aquatic life (United State Environmental Protection Agency). Keywords: Distribution; Heavy metal pollution; River; Surface water; Water quality protection.

The relative impacts of different types of land use on the surface water quality are yet to be ascertained and quantified. In this paper, the influence of different types of land use on surface water quality is investigated. Rain events samples from different land use in the central plateau, Iran, were analyzed for major ions. Statistical analyses were employed to examine the statistical relationships of land use and water quality on a regional scale in Iran central plateau. Principal component analysis was used to investigate the processes controlling the effects of land use on the water quality in this area. The higher correlations of range than other land uses with major ion, specifically pH and HCO3, were showed and it's maybe reflecting the effects of the season the samples were taken. Keywords: Surface water quality; Principal components analysis; Land use; Iran

The former Sullivan Mine was one of the world's largest producers of lead, zinc and silver, officially closing in 2001 after 92 years of active production. The former mine and mill areas contain large impoundments of tailings, waste rock, and other process wastes as a result of historical mining processes. Environmental controls, site assessment and mitigation measures to manage and protect surface water and groundwater quality have been in place since the 1960s. Large-scale characterisation of the surface water and groundwater systems was initiated in the mid 1990s. At the same time, incremental efforts to assess and mitigate mining-related impacts to these resources commenced, including: waste impoundment covers, seepage collection systems, mine de-watering, pumping well networks; and groundwater interception barriers, trenches and sand drains. In addition to these mitigation measures, a comprehensive risk assessment was performed culminating in a site-wide Risk Management Plan with annual surface water and groundwater monitoring programs. Long-term post-closure monitoring at a number of surface water and groundwater monitoring locations since 2001 have provided indicators of improving surface water and groundwater quality across both the former mine and mill areas. These long-term trends have confirmed predictions made through conceptual hydrogeological and geochemical models developed after closure. Monitoring in the tailings impoundments indicated loading to groundwater from acid rock drainage and metal leaching impacts in source areas has been reduced. Monitoring in downgradient areas suggested groundwater capture has been successful in reducing off-site loading. Surface water quality has improved in receiving creeks and rivers. In addition to mitigation measures implemented at the site, natural attenuation mechanisms originally predicted by geochemical modelling have also been confirmed by long-term trends in groundwater quality. The phased implementation of mitigation measures combined with targeted site assessment and a carefully defined Risk Management Plan with long-term monitoring have provided a cost-effective and successful solution for post-closure management of surface water and groundwater. Additional site assessment, mitigation measures and improvements to existing environmental controls will continue to be implemented on an as needed basis. Further improvements to groundwater and surface water quality are expected to be observed with planned long-term surface water and groundwater monitoring.

The domestication of wild plant species can begin with gathering and transport of propagules by Indigenous peoples. The effect on genomic composition, especially in clonal, self-incompatible perennials would be instantaneous and drastic with respect to new, anthropogenic populations subsequently established. Reductions in genetic diversity and mating capability would be symptomatic and the presence of unique alleles and genetic sequences would reveal the origins and ancestry of populations associated with archaeological sites. The current distribution of the Four Corners potato, Solanum jamesii Torr. in the Southwestern USA, may thus reflect the early stages of a domestication process that began with tuber transport. Herein genetic sequencing (GBS) data are used to further examine the hypothesis of domestication in this culturally significant species by sampling 25 archaeological and non-archaeological populations. Archaeological populations from Utah, Colorado and northern Arizona have lower levels of polymorphic loci, unique alleles, and heterozygosity than non-archaeological populations from the Mogollon region of central Arizona and New Mexico. Principle components analysis, Fst values, and structure analysis revealed that genetic relationships among archaeological populations did not correspond to geographic proximity. Populations in Escalante, Utah were related to those on the Mogollon Rim (400 km south) and had multiple origins and significant disjunctions with those populations in Bears Ears, Chaco Canyon, and Mesa Verde sites. Movement of tubers from the Mogollon region may have occurred many times and in multiple directions during the past, resulting in the complex genetic patterns seen in populations from across the Four Corners region.

Groundwater and surface water are among the principal resources used by all sectors for home, agricultural, and industrial purposes in the Uttar Pradesh district of Ghaziabad. The current study looked on Ghaziabad's groundwater and surface water quality. A total of five samples of surface water from the Hindon River and the Sahibabad Industrial Area were taken during the month of March 2020. Following analysis of samples using BIS 2012, it was found that the groundwater samples complied with IS 10500 and were suitable for use as drinking water. Contrarily, the water sample from the Hindon River is contaminated and unfit for drinking, bathing, swimming, fishing, etc. The government is urged to issue public notifications forbidding the use of this water in appropriate locations. Therefore, it is vital to periodically examine the water's properties from the perspective of different parameters like TDS, pH, Total Hardness, and others. Metallic heavy (i.e., Zinc, Lead, Iron, and Arsenicetc), A thorough assessment of amphibian-level organisms can reveal information about the quality of the water which is analysed using modern instruments of Noida Testing Laboratory under the ministry of Environment, Forest and Climate Change.