scholarly journals Report of progress of stream measurements for the calendar year 1905, Part XIII, The Great Basin and Pacific Ocean drainages in California, and Colorado River drainage below Gila River

1906 ◽  
2017 ◽  
Vol 39 (6) ◽  
pp. 431 ◽  
Author(s):  
T. A. Jones

Ecological restoration in the United States is growing in terms of the number, size, and diversity of projects. Such efforts are intended to ameliorate past environmental damage and to restore functioning ecosystems that deliver desired levels of ecosystem services. In nine current restoration case studies from across the continental United States, this paper details (1) the impacts of the original disturbance and compounding secondary issues that compel restoration, (2) the corrective practices applied to advance restoration goals, and (3) the prospects for recovery of ecosystem services, including those involving associated animal populations. Ecosystem-altering impacts include flood control (Kissimmee River), flood control and navigation (Atchafalaya Basin), damming for irrigation-water storage (Colorado River) and hydroelectric power (Elwha River), logging and fire suppression (longleaf pine forest), plant invasions that decrease fire-return intervals (Great Basin shrublands, Mojave Desert), nutrient and sediment loading of watersheds (Chesapeake Bay, Mississippi River delta), and conversion of natural lands to agriculture (tallgrass prairie). Animal species targeted for recovery include the greater sage-grouse (Great Basin shrublands), the red-cockaded woodpecker (longleaf pine forest), the south-western willow flycatcher (Colorado River and its tributaries), the desert tortoise (Mojave Desert), eight salmonid fish (Elwha River), and the blue crab and eastern oyster (Chesapeake Bay).


<em>Abstract</em>.—In the past 17 million years (myr), the topography and drainage systems of the northwestern United States were drastically modified by the Yellowstone–Snake River Plain (YSRP) hotspot and associated east–west extension of the Basin and Range Province. These geologic changes influenced distribution and diversification of Cutthroat Trout <em>Oncorhynchus clarkii</em> and allowed connections between Snake River, Colorado River, and Great Basin fish populations beginning in the late Miocene. Studies of detrital zircon grains in Miocene to Holocene fluvial sands of the Snake River document the eastward migration of the regional drainage divide from central Idaho to northwestern Wyoming. This migration was concomitant with the southwest migration of the North American tectonic plate over the YSRP hotspot. In the late Miocene and Pliocene, since 10 million years before present (Ma), the Chalk Hills and Glenns Ferry lake systems formed on the western Snake River Plain and were hosts to diverse fish fauna. The modern Snake River formed after 3 Ma with the cutting of Hells Canyon and integration of the Snake and Columbia River drainage. In the Great Basin south of the Snake River watershed, Lake Lahontan has a history that goes back to the Miocene. Connections between the western Snake River Plain and the Great Basin were recurrent over the past 10 myr. In southeastern Idaho, the Bear River has had a complex drainage interaction with the Snake River and Bonneville watersheds. Lake Bonneville, in northern Utah, grew during Pleistocene glacial climate regimes. The modern Bear River connection to Lake Bonneville was initiated about 50,000 years before the present. The integration of the Green River with the Colorado River occurred in the late Miocene, developing after breaking of Eocene connections between the Green River and streams draining to the Atlantic Ocean. In sum, geological constraints are compatible with patterns of fish fossils and genetic linkages and identify mechanisms of colonization and isolation of fish populations that have resulted in regional diversification of Cutthroat Trout.


1955 ◽  
Vol 20 (4Part1) ◽  
pp. 367-374 ◽  
Author(s):  
Paul H. Ezell

The area dealt with in this report is that portion of northwestern Sonora and southwestern Arizona bounded on the southwest by the Gulf of California, on the west by the Colorado River valley below the junction of the Gila River, on the north by the Gila River valley, and on the east by an imaginary line from the vicinity of Gila Bend south along the western edge of the Papago Reservation and thence southwest to the mouth of the Sonoyta River on the Gulf of California (Fig. 106). Within this area Sauer has suggested a boundary between the Piman-speaking people of southern Arizona and northern Sonora, and the Yuman-speaking tribes of the lower Colorado and Gila River valleys, based on linguistic affiliations described in early historical sources (Sauer 1934, map). On archaeological evidence Gifford has suggested that the locality between Punta La Cholla and the mouth of the Sonoyta River represented a point on an ethnic boundary (Gifford 1946: 221).


2015 ◽  
Vol 28 (15) ◽  
pp. 6096-6112 ◽  
Author(s):  
Kimberly Smith ◽  
Courtenay Strong ◽  
Shih-Yu Wang

Abstract The eastern Great Basin (GB) in the western United States is strongly affected by droughts that influence water management decisions. Precipitation that falls in the GB, particularly in the Great Salt Lake (GSL) basin encompassed by the GB, provides water for millions of people living along the Wasatch Front Range. Western U.S. precipitation is known to be influenced by El Niño–Southern Oscillation (ENSO) as well as the Pacific decadal oscillation (PDO) in the North Pacific. Historical connectivity between GB precipitation and Pacific Ocean sea surface temperatures (SSTs) on interannual to multidecadal time scales is evaluated for 20 models that participated in phase 5 of the Coupled Model Intercomparison Project (CMIP5). While the majority of the models had realistic ENSO and PDO spatial patterns in the SSTs, the simulated influence of these two modes on GB precipitation tended to be too strong for ENSO and too weak for PDO. Few models captured the connectivity at a quasi-decadal period influenced by the transition phase of the Pacific quasi-decadal oscillation (QDO; a recently identified climate mode that influences GB precipitation). Some of the discrepancies appear to stem from models not capturing the observed tendency for the PDO to modulate the sign of the ENSO–GB precipitation teleconnection. Of all of the models, CCSM4 most consistently captured observed connections between Pacific SST variability and GB precipitation on the examined time scales.


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