Flow, Salts, and Trace Elements in the Rio Grande: A Review

There are increasing concerns that water quality of the Rio Grande (or Rio Bravo) may be deteriorating mainly due to the recent expansion of the maquilas program and associated population relocation into the Border area. This review was conducted to assess the state of flow, salts, and trace elements in the Texas/Mexico portion of the Rio Grande and its tributaries. The data used included published and unpublished reports by federal, state, and some local sources. The total inflow into the Texas/Mexico portion of the Rio Grande (El Paso to Brownsville) since 1969 has averaged 4.51 billion m3 (3.65 million acre-ft) annually. Approximately 60 percent of the inflow is estimated to originate from the Mexican side. The largest flow of the Rio Grande occurs below Falcon Dam at an annual rate of 3.0 billion m3 (2.43 million acre-ft). No significant yearly trend of annual flow was detected either by a linear regression or the autocorrelation analysis for the last 21 years. The Rio Conchos, the Rio San Juan, and the Rio Salado are the major tributaries from the Mexican side and account, respectively, for 20, 10, and 10 percent of the total inflow into the Rio Grande. The Devils River and the Pecos River are two of the major tributaries from Texas and account, respectively, for 7.8 and 6.1 percent of the total inflow into the Rio Grande. The highest salinity of the Rio Grande occurs in the section from Fort Quitman to Presidio (2000 to 5000 mg L-1) and at the Pecos River (2000 to 4000 mg L-1). Salinity of the Rio Grande decreases below Presidio due to the confluence of the Rio Conchos, and it currently averages 860 mg L-1 at Amistad International Reservoir. However, salinity in this segment of the Rio Grande is increasing at an annual rate of 15 to 18 mg L-1. If these trends continue, salinity at Amistad Reservoir will exceed 1000 mg L-1 by the year 2000 or will become twice the salinity level of 1969 by 2004. Salinity below Amistad has been increasing at lower rates (9 to 10 mg L-1). Salinity of the Rio Conchos, the Rio San Juan, and the Pecos River has also been increasing at an annual rate of 8.5, 21, and 38 mg L-1, respectively. Salinity is flow-dependent at the upper reach and at Brownsville. Elsewhere, salinity is largely independent of the annual flow and has not yet attained the steady state. Sodicity of the main flow of the Rio Grande is at the range where soil particle dispersion begins (SAR of 3 to 4), and that of saline tail water below Fort Quitman and the Pecos River well exceeds the stability guideline. The sodicity of the Rio Grande water usually increases with increasing salinity, and the sodium adsorption ratio reaches close to 10. The annual salt inflow into the Rio Grande between Fort Quitman and Amistad Dam is estimated at 1.84 million tons, and that between Amistad and Falcon Dam at 1.17 million tons. Saline tail water of the Federal Middle Rio Grande project and the Pecos River contributes 48 percent of the salt load to the Rio Grande above Amistad Dam, while contributing only 21 percent to the flow. These two streams plus the Rio Salado contribute 50 percent of the salt load of the Rio Grande above Falcon Dam, while contributing 26 percent to the flow of the Rio Grande. Salts have been accumulating, especially in the segments above Amistad Dam. Existing database for trace elements is rather sketchy and is often inaccurate for some elements (e.g., Hg, Ag, and Cd). Nonetheless, most data indicate that dissolved concentrations of trace elements measured for the last 10 years at six monitoring stations along the main flow of the Rio Grande are low enough to meet the EPA primary drinking water standard, the proposed EPA criteria for livestock water supply, as well as guidelines for irrigation uses. However, dissolved concentrations of Cu, Pb, Hg and Ag often exceed the EPA chronic criteria for aquatic species protection, which are considerably more stringent than those for drinking water. Elevated levels of dissolved Hg concentrations are found in the upper reach (Elephant Butte down to Presidio) and elevated levels of dissolved Cu, Pb and V in salt marshes of the Lower Rio Grande. The concentrations of Cd, Cu, and Cr in pore water of the sediments in the upper reach appear to be many times higher than those in free water. The concentrations of many metals in fish samples collected from various locations along the Rio Grande often exceed the 85th national percentile established by the U.S. Fish and Wildlife Service. There is, however, no indications of Se problems along the Rio Grande. With few exceptions, the concentrations of total recoverable metals found in the sediment samples from the Rio Grande main stream are below or at the average values established for soil samples from the western states, except for Hg and Pb. Acid digestible contents of metals in sediments appear to be poorly correlated with dissolved metals or the metal concentrations in fish. The concentration of acid-digestible trace elements (Zn, Cu, Cd, Pb, Ni, Cr, and V) in soil samples from irrigated fields in the El Paso and the Juarez Valleys show some indications of Cu, Pb, and Zn accumulation. Even so, the levels of these metals are well below toxic levels for plant growth or for animal health concerns. The alkaline nature of the Rio Grande seems to help maintain relatively low dissolved concentrations of metals in water, but metals are probably accumulating in soils and sediments. Overall, this review indicates salts to be the major constraint for full utilization of water resources in the Rio Grande and that salinity is steadily increasing, especially above Amistad Dam. In these areas, salinity of the Rio Grande already exceeds the primary drinking water standard as well as the guidelines for production of high value horticultural crops. The continuing increase in salinity of Amistad Reservoir is of a special concern, as it may exceed the primary drinking water standard by as early as the year 2000 and could adversely affect high value crop production in the Lower Rio Grande. Trace element problems in the Rio Grande are sporadic and do not seem to be wide-spread at present, except from the view of aquatic species protection. There is a need to carry out a detailed salinity projection analysis, and to improve the accuracy of trace element monitoring and assessment of bioavailability indices for various ecosystems, especially in aquatic systems. Future research should also include water management options which target reuse of saline drainage water and disposal of wastewater away from the primary waterway of the Rio Grande to curtail salinization and trace element accumulation

Neoplastic transformation of mouse C3H 10T1/2 and Syrian hamster embryo cells by heavy ions

C3H 10T1/2 mouse-embryo fibroblasts were used for transformation experiments to study the effectiveness of various heavy ions with energies up to 20 MeV/u and LET values from 170 to 16.000 keV/μm. The transformation frequency per unit absorbed dose decreased with increasing ionization density; at the highest values of LET we found a decrease even of the transformation efficiency per unit fluence. Uranium ions at energies of 5, 9, and 16.3 MeV/u did not induced any transformation. In additional studies piimary Syrian hamster embryo cells (SHE) were exposed to heavy ions in order to characterize cytological and molecular changes which may be correlated with neoplastic transformation. Growth behaviour, chromosomal status, tumorigenicity in nude mice, and expression of oncogenes of transformed cell lines were examined

Re‐analysis of late Quaternary dust mass accumulation rates in Serbia using new luminescence chronology for loess–palaeosol sequence at Surduk

Despite numerous palaeoenvironmental investigations of loess–palaeosol sequences across the Carpathian Basin, well‐dated high‐resolution records are scarce. This paper presents a new high‐resolution chronology for the loess‐palaeosol sequence at Surduk (Serbia), based on optically stimulated luminescence (quartz) and post‐infrared infrared stimulated luminescence (polymineral) dating. The presented record spans 53–19 ka, with primary loess deposition occurring after 52±2 ka, and differs from previously published chronologies that relied on less precise and now superseded dating protocols. Based on the new chronology, mass accumulation rates (MAR s) for Surduk were constructed and compared with sites in the Carpathian Basin. The results demonstrate that accumulation periods across this area are not consistent in timing or rates. The high‐resolution dating strategy identifies a disturbance in sediment deposition that occurred after 45±2 ka and implies that site contains a hiatus. Finally, we show samples that failed routine dose recovery and preheat plateau tests, and had low fast ratios. Supported by bulk sample geochemical analysis it is proposed that a potential abrupt source shift, during the Last Glacial Maximum, may be the cause of the anomalous luminescence behaviour

Prevention of acute malnutrition: distribution of special nutritious foods and cash, and addressing underlying causes--what to recommend when, where, for whom, and how

Acute malnutrition is associated with increased morbidity and mortality risk. When episodes are prolonged or frequent, acute malnutrition is also associated with poor growth and development, which contributes to stunting Nutrition-specific and nutrition-sensitive strategies to prevent undernutrition during the first 1,000 days from conception to 24 months of age can reduce the risks of wasting, stunting, and micronutrient deficiencies. Under circumstances that exacerbate the underlying causes of undernutrition and increase the incidence of wasting, such as food insecurity related to lean seasons or emergencies, or increased incidence of illness, such as diarrhea or measles, additional efforts are required to prevent and treat wasting. Special nutritious foods directly meet the increased nutrient requirements of children at risk for wasting; assistance to vulnerable households, in the form of cash or food, enables households to better meet the food, health, and other needs of household members and may increase resilience; water, sanitation, and hygiene (WASH) and health interventions help prevent and address illness and hence reduce wasting risk. The contributions of specific interventions to reducing the incidence of wasting are difficult to assess under emergency conditions, due to ethical constraints and to the fact that multiple strategies are implemented at the same time. However, pragmatic studies under real-life circumstances, using different designs, e.g., including a group receiving "best possible" treatment, can provide evidence about what works, to what extent, at what cost, and under which circumstances. Programs should address the most important causes in given contexts, be feasible to implement at scale, and assess implementation, coverage, and outcomes

Development of a Unique Student Pharmacist Internship in a Primary Care Provider System

Purpose: To describe a unique pharmacy intern program in a group of federally qualified health center (FQHC) outpatient primary care provider clinics. Summary: A pharmacy intern program was created at the North Central Nursing Clinics in Indiana, a group of four FQHC outpatient primary care provider facilities. Intern-performed tasks included: Prior authorization (PA) requests, medication assistance program (MAP) applications, sample procurement and inventory, and contraceptive devices for implantation inventory management. Interns interacted with clinic administration, nurse practitioners, and medical staff to complete their assigned responsibilities. Over a one-year period, the interns completed documentation on more than 2000 charts during a combined 12 h a week. Interns identified the interprofessional interactions as the most beneficial experience, while providers acknowledged no difference in the processing of paperwork during the transition of duties from pharmacy fellow to intern. Conclusion: This unique pharmacy intern program was successfully created and implemented in a primary care provider office, resulting in learning opportunities for pharmacy interns, as well as operational efficiencies to fellows, providers, and the organization

Global assessment of nitrogen deposition effects on terrestrial plant diversity : a synthesis

Atmospheric nitrogen (N) deposition is it recognized threat to plant diversity ill temperate and northern parts of Europe and North America. This paper assesses evidence from field experiments for N deposition effects and thresholds for terrestrial plant diversity protection across a latitudinal range of main categories of ecosystems. from arctic and boreal systems to tropical forests. Current thinking on the mechanisms of N deposition effects on plant diversity, the global distribution of G200 ecoregions, and current and future (2030) estimates of atmospheric N-deposition rates are then used to identify the risks to plant diversity in all major ecosystem types now and in the future. This synthesis paper clearly shows that N accumulation is the main driver of changes to species composition across the whole range of different ecosystem types by driving the competitive interactions that lead to composition change and/or making conditions unfavorable for some species. Other effects such its direct toxicity of nitrogen gases and aerosols long-term negative effects of increased ammonium and ammonia availability, soil-mediated effects of acidification, and secondary stress and disturbance are more ecosystem, and site-specific and often play a supporting role. N deposition effects in mediterranean ecosystems have now been identified, leading to a first estimate of an effect threshold. Importantly, ecosystems thought of as not N limited, such as tropical and subtropical systems, may be more vulnerable in the regeneration phase. in situations where heterogeneity in N availability is reduced by atmospheric N deposition, on sandy soils, or in montane areas. Critical loads are effect thresholds for N deposition. and the critical load concept has helped European governments make progress toward reducing N loads on sensitive ecosystems. More needs to be done in Europe and North America. especially for the more sensitive ecosystem types. including several ecosystems of high conservation importance. The results of this assessment Show that the Vulnerable regions outside Europe and North America which have not received enough attention are ecoregions in eastern and Southern Asia (China, India), an important part of the mediterranean ecoregion (California, southern Europe). and in the coming decades several subtropical and tropical parts of Latin America and Africa. Reductions in plant diversity by increased atmospheric N deposition may be more widespread than first thought, and more targeted Studies are required in low background areas, especially in the G200 ecoregions

“Tales and Adventures”: G.A. Henty’s Union Jack and the Competitive World of Publishing for Boys in the 1880s’

In the competitive publishing environment of the late nineteenth century, writers and magazines had to distinguish themselves carefully from potential rivals. This article examines how G.A. Henty’s quality boys’ weekly, Union Jack (1880-83), attempted to secure a niche in the juvenile publishing market by deliberately distinguishing itself from other papers as a literary, imperialist and “healthy” publication. The article explores the design and marketing techniques of the magazine, its status as a fiction paper, the high calibre of its contributors, and its aggressive rhetoric in targeting an exclusively masculine audience. It argues that while Union Jack was marketed as a niche publication, it eventually failed to distinguish itself sufficiently to survive in an extremely competitive environment

Characteristics of tropospheric ozone depletion events in the Arctic spring: analysis of the ARCTAS, ARCPAC, and ARCIONS measurements and satellite BrO observations

Arctic ozone depletion events (ODEs) are caused by halogen catalyzed ozone loss. In situ chemistry, advection of ozone-poor air mass, and vertical mixing in the lower troposphere are important factors affecting ODEs. To better characterize the ODEs, we analyze the combined set of surface, ozonesonde, and aircraft in situ measurements of ozone and bromine compounds during the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS), the Aerosol, Radiation, and Cloud Processes affecting Arctic Climate (ARCPAC), and the Arctic Intensive Ozonesonde Network Study (ARCIONS) experiments (April 2008). Tropospheric BrO columns retrieved from satellite measurements and back trajectory calculations are also used to investigate the characteristics of observed ODEs. In situ observations from these field experiments are inadequate to validate tropospheric BrO columns derived from satellite measurements. In view of this difficulty, we construct an ensemble of tropospheric column BrO estimates from two satellite (OMI and GOME-2) measurements and with three independent methods of calculating stratospheric BrO columns. Furthermore, we select analysis methods that do not depend on the absolute magnitude of column BrO, such as time-lagged correlation analysis of ozone and tropospheric column BrO, to understand characteristics of ODEs. Time-lagged correlation analysis between in situ (surface and ozonesonde) measurements of ozone and satellite derived tropospheric BrO columns indicates that the ODEs are due to either local halogen-driven ozone loss or short-range (∼1 day) transport from nearby regions with ozone depletion. The effect of in situ ozone loss is also evident in the diurnal variation difference between low (10th and 25th percentiles) and higher percentiles of surface ozone concentrations at Alert, Canada. Aircraft observations indicate low-ozone air mass transported from adjacent high-BrO regions. Correlation analyses of ozone with potential temperature and time-lagged tropospheric BrO column show that the vertical extent of local ozone loss is surprisingly deep (1–2 km) at Resolute and Churchill, Canada. The unstable boundary layer during ODEs at Churchill could potentially provide a source of free-tropospheric BrO through convective transport and explain the significant negative correlation between free-tropospheric ozone and tropospheric BrO column at this site