Verde Rivers Research Articles

Numerical modeling of a multilayer coastal aquifer in extreme drought with additional exploitation and impact on its associated ecosystems: Júcar river and La Albufera de Valencia (Plana de Valencia Sur, Spain)

La Plana de Valencia Sur (MASub 080.142) constitutes a coastal hydrogeological system with high potential, which gives it great aptitude so that it can be considered as a strategic aquifer, understanding as such that it can be exploited in a short-term and intensive way during times of drought in order to compensate for the deficit created in demand systems. For this purpose, in the mid-90s and the first decade of this century, a large number of groundwaters catchments were built that were used during the extremely dry period from 2005 to 2008. This additional and scheduled exploitation required a meticulous piezometric and hydrochemical monitoring, as well as the volumes extracted, which was carried out by the Júcar Hydrographic Confederation (CHJ) and the Geological Survey of Spain (IGME). The data obtained allowed us to know the response of the system to a situation of exceptional water stress and to develop a detailed model of underground flow with the Visual MODFLOW software. The model domain, discretised in 4,357 cells of 359x359 m, covers an area of 56,15 km2 and consists of four layers equivalent to the four geological formations that comprise it. With its calibration and adjustment in steady state and transitory flow regimes, the aquifer balance has been determined, as well as its behaviour and evolution. One of the most relevant aspects is that it incorporates in a different way the main ecosystems dependent on groundwater: Júcar and Verde rivers, ullales or springs, drainage channels and La Albufera lake, in addition to direct outlets to the sea. The conclusions obtained include, at a general level, the suitability of the actions carried out and their environmental viability, confirming its good characteristics as a strategic aquifer, as well as its ability to be exploited intensively during times of extreme weather conditions. It also analyses, in a particularized way, the consequences that the intensive exploitation of the system has had on each of the different elements that make up its water balance, which has allowed us to know the conditions suffered by the two large ecosystems with which it is related, Júcar River and La Albufera de Valencia, throughout the period analysed.

Drainage integration of the Salt and Verde rivers in a Basin and Range extensional landscape, central Arizona, USA

The Salt River and Verde River watersheds provide downstream metropolitan Phoenix, Arizona, USA with much of its water supply, and this paper explains how these rivers integrated in an extensional tectonic setting. Near the end of the Pliocene, segments of the proto-Salt and proto-Verde watersheds of central Arizona consisted of local drainage networks supplying water and sediment into internally drained basins, including depressions occupied by late Pliocene natural lakes occupying the Verde Valley and Tonto basins. A key location, the lower Verde River valley (LVRV), is where the modern-day drainages of the Salt and Verde now meet downstream of these Pliocene lakes. At the time of the Nomlaki tuff deposition ~3.3 Ma, a condition of sediment overfill existed in the LVRV, although there was no exoreic drainage and a playa was still maintained. A fanglomerate unit, named here the Rolls formation, spilled over a bedrock sill and an alluvial-fan ramp transported sediment into the Higley Basin that underlies the eastern part of metropolitan Phoenix. Lithologies of preserved remnants of this Pliocene alluvial-fan system match well cuttings of buried sediment in the Higley Basin with a cosmogenic burial isochron age of 3.90 ± 0.70 Ma. Based on cosmogenic burial isochron ages, ancestral Salt River gravels started depositing on top of this fan ramp between 2.8 and 2.2 Ma. Deposition of Salt and Verde river gravels in the Higley Basin continued for ~2 million years and eventually led to an aggradational piracy event that overtopped a bedrock ridge immediately east of Phoenix's Sky Harbor Airport. A cosmogenic burial age of 460 ± 23 ka is a rough maximum age for this river avulsion that relocated the Salt River into the Luke Basin that underlies western metropolitan Phoenix. Available chronometric data are not precise enough to determine whether the Salt River or Gila River integrated first. All of the exoreic rivers of western North America's Basin and Range Province — the lower Colorado, Gila, Rio Grande, Salt, and Verde rivers — employed lake overflow to integrate across half-graben, graben, rift and supradetachment tectonic settings.

Conservation status of Astyanax biotae (Characiformes: Characidae) in Mato Grosso do Sul, upper Paraná River basin, Brazil

Astyanax biotae é uma espécie originalmente descrita em um afluente do Rio Paranapanema, bacia do alto Paraná. Durante amostragens realizadas em drenagens dos rios Ivinhema e Verde, no sistema do alto Paraná, em Mato Grosso do Sul, exemplares de A. biotae foram coletados em cabeceiras de pequenos riachos e em lagoas de várzea, tanto em Unidades de Conservação como em áreas de agricultura intensiva. Os dados morfomerísticos de 20 indivíduos analisados foram similares aos da série-tipo. Exemplares testemunhos estão depositados nas coleções ictiológicas da UFMS (ZUFMS), UEMS (CPUEMS) e UNESP (DZSJRP). Com base nos critérios da IUCN, sugerimos sua classificação como Menos Preocupante (LC) no estado de Mato Grosso do Sul, considerando principalmente a inexistência de ameaças efetivas em duas das áreas de ocorrência da espécie, situadas dentro de Unidades de Conservação. No entanto, reforçamos a urgência em medidas para a proteção das regiões de cabeceiras de riachos, a fim de evitar o aumento do desmatamento, assoreamento e poluição agrícola, problemas recorrentes no Cerrado, que comprometem severamente a manutenção desses hábitats e suas espécies. É necessário investir em estudos sobre a biologia da espécie e ampliar as amostragens, buscando diminuir os vazios amostrais ainda existentes nas drenagens estaduais.

Puntos de referencias biológicos para la ordenación pesquera de Ageneiosus pardalis (Auchenipteridae) en el embalse Urrá

Se estimaron puntos de referencias biológicos de la doncella Ageneiosus pardalis en el embalse Urrá y ríos aportantes como mortalidad por pesca máxima (Fmax), mortalidad por pesca a 10 % (F0,1), mortalidad por pesca actual (F2015), mortalidad por pesca a máximo rendimiento económico (FMRE), máximo rendimiento económico (MRE) y máximo rendimiento sostenible (MRS). Además, se analizó la situación de la doncella bajo tres escenarios: 1) estado actual, 2) prohibición de pesca con mallas por dos meses (abril y noviembre) y 3) prohibición de pesca con malla por dos meses más el cumplimiento de la zona de reserva (colas Sinú y Verde). Las estimaciones de Fmax (1,1 año-1), F0,1 (0,6 año-1) y F2015 (1,2 año-1) sugieren que la especie está al límite de la sobrepesca. Para obtener un MRE ($130,6 millones de pesos), la FMRE debe ser de 0,6 año-1 y un MRS de 28,8 tm. En 2015, el 81 % de la doncella capturada estuvo por debajo de la talla mínima legal vigente (32 cm LE) y 51 % por debajo la talla de media de madurez estimada (26,6 cm LE). Los resultados del presente estudio permiten concluir que la población de doncella se encuentra en etapa inicial de sobrepesca y se recomienda la prohibición de la pesca con redes agalleras y la veda permanente en las colas del embalse con los ríos Sinú y Verde como el mejor escenario para esta especie.

Pediment response to drainage basin evolution in south-central Arizona

The Sonoran Desert portion of the Basin and Range physiographic province contains a number of streams that now flow across once-closed basins. We explore here the research questions of if and how granitic rock pediments respond to the transition from rimming endorheic basins to bordering through-flowing streams. Granitic rock pediments of the northern Usery and eastern McDowell Mountains once graded to the closed Miocene–Pliocene Pemberton basin that occupied the present-day location of the confluence of the Salt and Verde Rivers. The process of lake overflow, which integrated these rivers, first aggraded fill terraces that, in turn, caused aggradation of a mantle of transported grus on bedrock pediments. Subsequent episodic incision of the Salt and Verde rivers lowered the base level; this led to the development of erosional features such as rolling topography of a degrading pediment mantle; exposure of the former piedmont angle and its associated zones of enhanced bedrock decay and regolith carbonate; and exposure of spheroidally weathered bedrock and emerging tors, some of which experienced 20th century erosion. The granitic pediments of the former Pemberton Basin, which now transport grus to the Salt and Verde rivers, have actively adjusted to aggradational and degradational events associated with drainage integration and do not appear to be inherited from an ancient wet climatic interval.

TOWARD COMMON GROUND

Throughout the Southwestern United States and Mesoamerica, indigenous peoples have used running and racing as means of religious expression, environmental control, personal sacrifice, and community cohesion. In such contexts, the physical location of racing was often unimportant, and manufactured facilities were relatively rare. In the Perry Mesa region of Central Arizona, however, constructed racetracks were highly formalized and elaborated. Along with their associated plazas, they represent the only recognized form of communal architecture on Perry Mesa. We study these features with the goal of better understanding the behaviors and beliefs of the people who lived along the Middle Agua Fria and Verde rivers prehistorically and how their communities fit into the surrounding social landscape. Our data suggest that rapid aggregation from disparate origins led to the abdication of dissimilar ritual architecture and a subsequent focus on racing and feasting, ritual activities probably familiar to each group. We argue that concentration on shared ritual and the avoidance of dissimilarity allowed for the emergence of a new identity in a time of dramatic social change.

Tree ring record of streamflow and drought in the upper Snake River

Tree ring samples collected near the Snake River headwaters were augmented with preexisting tree ring chronologies to create a 415 year reconstruction of upper Snake River streamflow, extending the short instrumental record and providing the first description of multicentury water supply variability in this river. Results indicate that the region's early 21st century drought is severe even in the context of long‐term climatic variability and that the instrumental record is representative of low‐flow individual years. In terms of overall magnitude, droughts of the recent past are eclipsed by a sustained low‐flow period lasting for over 30 years in the early to mid‐1600s. A comparison of reconstructed Snake River flow with streamflow reconstructions of the Colorado, Sacramento, and Verde rivers suggests that changes in the predominance of zonal versus meridional atmospheric flow may have influenced drought patterns in the western United States through time.

Selected minor and trace elements from water bodies of western Paraguay

Minor and trace elements composition of bottom sediments from water bodies in Western Paraguay have been investigated by XRF techniques to determine their correlation as well as provenance. The analysis of complex spectra was performed by the AXIL software and the quantitative analysis by the QAES software. Analyzed trace elements were the refractory elements Rb, Sr, Y, Zr, Nb, Ba, La, Ce, Pr, Nd, Zr, y and other HFSE as Cr, Ni, Cu, together with Zn. Minor elements were Ti, Mn, Fe which are often to the above refractories related. According to their normalized spidergrams two sets of sediments can be differentiated. Those from Pilcomayo and Verde rivers as well as from km164-Wetland show light rare earth elements (LREE) enrichment, negative Nb and Ti anomalies and no spike at Zr. On the other hand, sediments from Confuso, Aguaray(Jehe), Negro and Montelindo rivers have spidergrams very alike, with strong negative anomalies at Nb, Nd and Ti whereas a positive at Zr. Further, in the former there is a strong correlation of Fe versus the refractory elements; such a correlation does not exist in the latter. The sediments from the Pilcomayo & Verde Rivers and from the km164-Wetland evolved as the sub-Andean/Andean metamorphic/sedimentary materials.

Agricultural influence on the hydrogeochemistry of the sub‐basins of the Verde, Entre Ribeiros and Escuro Rivers of Paracatu Hydrographic Basin (MG) – Brazil

PurposeOf the numerous hydrogeochemical river‐water transformations provoked by intense and irrational soil practices, heavy metal contamination by agrochemical usage is the most worrisome. Long‐term metal accumulation can be transported by rainwater, during storms, contaminating rivers. Data on this type of contamination are still scarce, principally in developing countries, such as Brazil. This paper aims to evaluate the influence of agricultural activities on the hydrogeochemistry of the Paracatu River's sub‐basins.Design/methodology/approachFrom a total of 77 points along three sub‐basins, water samples were taken for heavy metal and trace element analyses using spectrometry of atomic emission through plasma (ICP‐OES, Spectro Ciros CCD). The principal water‐quality parameters, such as pH, turbidity, conductivity, oxi‐reduction potential, total dissolved solids (TDS), temperature and dissolved oxygen were measured in situ.FindingsBy incorporating a small drainage area at the monitoring points, it was possible to perceive agriculture's influence (in the form of heavy metal contamination from fertilizers and pesticides) on the water courses.Research limitations/implicationsAlthough the research was carried out at a total of 77 points for water collection, data are from just one wet season, and need to be repeated.Practical implicationsThe results demonstrate a need for monitoring the areas involved with agricultural activities, not only along the main river, but also along small streams that compose the Paracatu Basin.Originality/valueThere is no published literature on this subject regarding the three studied basins.

Scenarios of metal concentrations in the Arcediano Dam (State of Jalisco, Mexico)

The city of Guadalajara, Jalisco, Mexico has 4.1 million inhabitants and a serious deficit in water supply. Once constructed, the Arcediano Dam will catch waters from the Verde and Santiago rivers, and after treatment will provide water to the city. The present study was undertaken to formulate scenarios and estimate risks of polluting the water that will be collected in the dam from the release of contaminants accumulated in sediments. Desorption of metals from sediments was estimated through sampling of water and sediments, chemical analyses of the environmental samples, and numerical modeling of the water–sediment interactions. Water quality generally increased as the river flowed downstream from the El Salto sampling station to the site where the Arcediano Dam will be constructed. Aluminum exceeded the Mexican Criterion for Drinking Water Supply (MCDWS), at all sampling stations, whereas iron and manganese surpassed the criteria at some stations. Trace metals were below their respective criteria. For sediment samples in the river, chrome, copper and zinc exceeded the Canadian Interim Sediment Quality Guidelines (ISQG), whereas manganese and nickel exceeded the probable effect level (PEL). Other metals were below these limits. With exception of the El Salto sampling station, metals were mostly enriched in iron-containing sediments, followed by aluminum-containing clays and, to a lesser extent, by manganese oxides. Therefore, the interaction of metals with iron oxides was considered as the controlling adsorption mechanism. Simulations to estimate risks of water contamination by desorption of metals from sediments indicate that manganese and nickel may reach concentrations higher than the CDWS. In some cases, dissolved concentrations of lead and chrome may be higher than the respective CDWS, especially under conditions of high accumulation of sediments in the dam. Arsenic, copper and mercury concentrations did not exceed the CDWS under the simulated conditions.

Sources and transport of organic carbon in an Arizona river-reservoir system

Sources and transport of organic carbon were studied in two large, Sonoran desert watersheds (Salt and Verde rivers) and a two-reservoir system on the Verde River. Total organic carbon (TOC) concentrations in the unregulated rivers above the reservoirs did not follow a simple relationship with flow. TOC concentrations usually declined during spring runoff and reached low concentrations (1–3 mg L −1) by early summer. In most years, distinct peaks (10–30 mg L −1) occurred in late summer, coincident with small but abrupt increases in flow associated with the first monsoon rains. A two-reservoir mass balance showed that 72% of the particulate organic carbon (POC) input was retained, probably due largely to simple sedimentation. Production of dissolved organic carbon (DOC) within the reservoir was 41% of the inflow loading, even though the reservoirs accounted for only 0.14% of the watershed area. Reservoir DOC production comprised a large fraction of total watershed production because upstream DOC production was extremely low (0.2 g C m −2 yr −1), the reservoirs were moderately productive, and water residence times were fairly long during most of the year. We postulate that reservoirs are major contributors to total watershed DOC production in arid regions.

Small Site Function and Duration of Occupation in the Hohokam Northern Periphery

A site typology developed for the Hohokam core area in the Phoenix Basin is evaluated for sites in the northern periphery using excavated data from small sites on the New and Verde rivers. Assumed differences in the tasks carried out at limited activity locations, field houses, farmsteads, and hamlets are examined using the ceramic and lithic assemblages recovered at these sites. This study evaluates the applicability of the Hohokam site typology to sites outside of the Phoenix Basin and the appropriateness of functionally based site typologies in general. An alternative interpretation of small sites is offered relying on differences in duration of occupation, rather than differences in function. Additionally, the analysis suggests the New River and Verde River areas may have been exploited in different ways by the Hohokam.

Flood plain dwellers' perception of the flood hazard in Tucson, Arizona

The study analyzes the perception of the flood hazard of 162 residents living within the 100 year floodplains of the Rillito, Santa Cruz, Pantano and Tanque Verde rivers in Tucson, Arizona. Results of the interviews indicate that the floodplain dwellers have no real appreciation of the flood danger and tend to minimize the extent of the damage that might result from a severe flood. Suggested user solutions were almost entirely technological involving channelization, dam construction, etc., and the residents feel that responsibility for handling the flood problem rests with government. The low personal assessment of the flood danger, the faith in technological solutions and the reliance on government has important implications for decision makers and resource managers who will need to devise strategies to make the residents more aware not only of the risks of living in the floodplain, but also of the wide range of non-technological alternatives that can offer some measure of protection.

Helminth Fauna of Suckers (Catostomidae) of the Gila River System, Arizona. II. Five Parasites from Catostomus spp.

Isoglaridacris hexacotyle (Linton, 1897) Mackiewicz, 1968 (Cestoda: Caryophyllaeidae), metacercariae of Clinostomum marginatum Rudolphi, 1819 (Trematoda: Clinostomidae) and Ornithodiplostomum ptychocheilus Faust, 1917 (Trematoda: Strigeidae), Neoechinorhynchus sp. Hamann, 1892 (Acanthocephala: Neoechinorhynchidae), and Illinobdella moorei Meyer, 1940 (Hirudinea: Piscicolidae) were recovered from Catostomus iinsignis and C. clarki from one or more of the following localities: Upper and Lower Verde and Salt rivers, tributaries of the Gila River. All but the first parasite are new host and locality records. Methods of fish capture and processing of worms, notes on the ecology and food habits of hosts, sites of infection, host-parasite interrelationships of the five parasites, and a morphological growth study of the first two are included. INTRODUCTION Between July 1966 and January 1967, 200 Catostomus clarki were captured from the Upper and Lower Salt, Verde, and San Pedro rivers of the Gila River, Arizona, and 375 C. insignis from all but the Upper San Pedro River (Amin, 1968). All were systematically examined for helminth parasites, which were absent from the San Pedro River. This is the second and last paper of this series. MATERIALS AND METHODS Native suckers, genus Catostomus, were obtained from streams by seining, gill netting, or shocking using the current supplied by a 110-v 900-w generator. The fish, always examined within 24-38 hours after capture, were kept, prior to examination, covered with ice in coolers, in a cold room (about 5 C), after which they were handled individually. Additional specimens were placed in tightly sealed plastic bags, quick-frozen by placing in another cold room (about -15 C), and were thawed shortly before dissection. Procedures used in dissection of the hosts and processing of I. hexacotyle, C. marginatum, 0. ptychocheilus, and I. moorei were previously described (Amin, 1969). Acanthocephalan worms recovered were not permanently mounted. Upon recovery, they were placed in 70% alcohol; an equal volume of glycerine was then added and the vials containing the worms were placed in a warm place after loosening the vial caps. A period of 2-4 weeks was necessary for the complete evaporation of alcohol and the 1 Abstracted from a dissertation submitted in partial fulfillment of the requirements of the Doctor of Philosophy degree in zoology at Arizona State University, Tempe, Arizona 85281.

Progress in developing multiple-use forest watershed production models

Developing a scientific basis for multiple-use management of millions of acres of publicly owned watersheds in the Southwest presents a big challenge to applications of regional science and the economics of production. Watershed managers are faced with hard problems in adjusting resource outputs to major changes in demand. Watershed conditions are extremely complex and diverse. Remarkably few data are available on production function and product-product relations. Important outputs are not valued in markets. Research is underway on the watersheds of the Salt and Verde rivers in Arizona to find how to redirect management to: (i) produce more water, while at the same time providing for (2) expected increases in wildland recreation use, as well as (3) sustained demand for timber and grazing. This paper reviews this work with particular attention to development of basic models for analysis and decisionmaking in multiple-use wildland watershed management. Needs for coordinating levels of analysis are outlined.