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EVALUATING TWO RAINWATER HARVESTING SYSTEMS IN AN URBAN SETTING IN oregon'S WILLAMETTE VALLEY

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Journal of Green Building 2017年第1期12卷 1-10页

作者： Conner Olsen Alexander Kowalewski Micah Gould John Lambrinos Department of Horticulture Turfgrass Management ProgramOregon State UniversityCorvallisOR 97331-7304

INTRODUCTION The recent trend toward more extreme periods of drought has been a shock to the residents of the Pacific Northwest-many of whom have relied upon heavy water-use in the summer months in order to make a living(*** of grass seed and sod,berries,or nursery crops),or to maintain their landscapes at high levels(*** homeowners,recreational facilities,or commercial properties).Further-more,population growth has reached the point where even an average year of pre-cipitation has proven insufficient for urbanities that had not previously experienced issues with water scarcity(McDonald et al.,2011).This modern climate scenario has forced people of the Pacific Northwest,and people from all around the world,to rethink their water-use strategies,as the global trend has shifted toward greater sustainability(Tilman,2001;McDonald et al.,2011).

关键词： rainwater-harvesting system subsurface matrix storage cistern pedal-powered pump

Characterization and Propagation of Historical and Projected Droughts in the Umatilla River Basin, oregon, USA

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Advances in Atmospheric Sciences 2024年第2期41卷 247-262,I0020-I0028页

作者： Sudip GAUTAM Alok SAMANTARAY Meghna BABBAR-SEBENS Meenu RAMADAS School of Civil and Construction Engineering Oregon State UniversityCorvallisOR 97331USA School of Infrastructure Indian Institute of TechnologyBhubaneswarOdisha 752050India

Climate change is expected to have long-term impacts on drought and wildfire risks in oregon as summers continue to become warmer and drier. This paper investigates the projected changes in drought characteristics and drought propagation in the Umatilla River Basin in northeastern oregon for mid-century(2030–2059) and late-century(2070–2099) climate scenarios. Drought characteristics for projected climates were determined using downscaled CMIP5 climate datasets from ten climate models and Soil and Water Assessment Tool to simulate effects on hydrologic processes. Short-term(three months) drought characteristics(frequency, duration, and severity) were analyzed using four drought indices, including the Standardized Precipitation Index(SPI-3), Standardized Precipitation-Evapotranspiration Index(SPEI-3), Standardized Streamflow Index(SSI-3), and the Standardized Soil Moisture Index(SSMI-3). Results indicate that short-term meteorological droughts are projected to become more prevalent, with up to a 20% increase in the frequency of SPI-3drought events. Short-term hydrological droughts are projected to become more frequent(average increase of 11% in frequency of SSI-3 drought events), more severe, and longer in duration(average increase of 8% for short-term droughts).Similarly, short-term agricultural droughts are projected to become more frequent(average increase of 28% in frequency of SSMI-3 drought events) but slightly shorter in duration(average decrease of 4%) in the future. Historically, drought propagation time from meteorological to hydrological drought is shorter than from meteorological to agricultural drought in most sub-basins. For the projected climate scenarios, the decrease in drought propagation time will likely stress the timing and capacity of water supply in the basin for irrigation and other uses.

关键词： Umatilla drought SPI SPEI SSI SSMI

Effects of western juniper(Juniperus occidentalis)control on ecosystem nitrogen stocks in central oregon,USA

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Journal of Plant Ecology 2021年第6期14卷 1073-1089页

作者： Mohamed A.B.Abdallah Ricardo Mata-González Jay S.Noller Carlos G.Ochoa Department of Animal and Rangeland Sciences Oregon State UniversityCorvallisOR 97331USA Department of Crop and Soil Science Oregon State UniversityCorvallisOR 97331USA

Aims In the oregon of USA,the control of western juniper(Juniperus occidentalis)is an accepted rangeland management practice to restore sagebrush steppe habitats of importance to wildlife and *** effects of juniper cutting on ecosystem nitrogen,however,have not been well addressed although woody plant control has important implications for local watershed management and regional nitrogen *** We quantified ecosystem nitrogen stocks in two adjacent watersheds,comprised of a treated watershed(most juniper removed)and an untreated watershed(juniper not removed).Thirteen years after juniper removal,we measured aboveground nitrogen stocks for juniper trees,shrubs,grasses and litter in both *** also measured belowground nitrogen stocks(roots and soil)in both watersheds at two soil depths(0–25 and 25–50 cm).Important Findings Aboveground nitrogen stocks were 6.9 times greater in the untreated than in the treated watershed considering the much larger aboveground ***,root nitrogen stocks were 3.1 times greater in the treated one due to the gain of understory root biomass associated with juniper *** nitrogen stocks at both 0–25 and 25–50 cm depths were not affected by juniper ***,total ecosystem nitrogen stocks did not differ between the treated(9536 kg N ha−1)and untreated(9456 kg N ha−1)*** greatest ecosystem nitrogen accumulation(at least 95%total ecosystem nitrogen)resided belowground(soil 0–50 cm and roots)in both *** study provides evidence that the benefits of juniper removal can be attained without significantly affecting the capacity of ecosystem nitrogen storage.

关键词： aboveground nitrogen stock belowground nitrogen stock ecosystem nitrogen Juniperus occidentalis soil nitrogen woody plant encroachment

Urban Growth Management through Travel Demand Modeling in Washington and oregon

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Journal of Traffic and Transportation Engineering 2018年第6期6卷 255-260页

作者： Jinxiang Ren oregon Department of Transportation 55513th St.NE#2SalemOregon 97301USA

Among the fast growing states in the USA,the States of Washington and oregon have enacted legislative land use and transportation concurrency/balancing planning policies for orderly urban growth management since 1990 and 1991,*** or urban travel demand forecasting models play an instrumental role in implementing the Washington GMA(Growth Management Act)and the oregon TPR(Transportation Planning Rule).Both program-and project-level modeling approaches to urban land use/transportation system management are evaluated through the selected cities in Washington and oregon.

关键词： Urban growth management travel demand modeling transportation planning land use-transportation concurrency

Winter Rain versus Snow in Headwater Catchments: Responses of an Unconfined Pumice Aquifer, South-Central oregon, USA

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Journal of Water Resource and Protection 2018年第4期10卷 461-492页

作者： Michael L. Cummings David A. Eibert Department of Geology Portland State University Portland Oregon

Winter precipitation in two headwaters catchments (elevation ~1600 m) in the rain shadow of the Cascades volcanic arc in south-central oregon normally falls as snow. However, in water year 2015, winter precipitation fell mainly as rain. An eight year study of the unconfined pumice aquifer allowed inter-annual comparison of groundwater recharge during the freshet and discharge during the growing season. During these water years precipitation ranged from 67% (WY2014) to 132% (WY2017) of the 30 year average, and included the rain dominated winter of WY2015 when precipitation during the water year was 98% of the 30 year average. Change in storage in the pumice aquifer was estimated from thickness of the pumice deposit and depth to water table from the ground surface. Measurements were made where 1) the pumice aquifer was exposed at the surface;2) where the aquifer was partially eroded and overlain by either alluvium or lacustrine glassy silt to fine sand;3) fens where the partially eroded aquifer was overlain by peat;and 4) monitoring wells drilled through the pumice aquifer into bedrock. In all settings, groundwater storage in the pumice aquifer following the rain-dominated winter of WY2015 was similar or less than storage following the drought of WY2014 when winter precipitation fell as snow. Storage at the end of WY2014 and WY2015 was the least observed in the eight year study. Winter-time rain during WY2015 produced runoff rather than storage in snow pack. Runoff conveyed from the catchments by flow in stream reaches normally dry from late summer through the winter months. Rain-dominated winter precipitation stresses the perched pumice aquifer. Winter storms starting as rain and turning late to snow and ground-freezing temperatures lead to runoff during the next rain-dominated precipitation event. These patterns produced stream flow in channels that are commonly dry during the winter, reduced near-surface groundwater storage in the pumice aquifer, muted springtime f

关键词： Unconfined Pumice Aquifer Headwater Catchment Winter Precipitation

Eelgrass and Macroalgae Loss in an oregon Estuary: Consequences for Ocean Acidification and Hypoxia

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Ocean-Land-Atmosphere Research 2023年第1期2卷 267-284页

作者： Caitlin L.Magel Sally D.Hacker Francis Chan Alicia R.Helms Department of Integrative Biology Oregon State UniversityCorvallisOR 97331USA South Slough National Estuarine Research Reserve CharlestonOR 97420USA

Estuarine macrophytes are proposed to influence ocean acidification and hypoxia(OAH)via the uptake(release)of inorganic carbon(oxygen)during *** extent to which macrophytes mitigate OAH in estuaries depends on the interaction between variable environmental conditions and macrophyte production over space and *** explore these complexities in detail,we considered the potential causes and consequences of intertidal eelgrass and macroalgae declines in a *** Northwest *** compiled and analyzed a record of eelgrass(Zostera marina)and ulvoid macroalgae along with a broad suite of environmental conditions over 15 years(2004 to 2019)at 3 sites along an estuarine gradient in South Slough,*** analysis showed that declining macrophyte biomass coincided with increasing temperature(water and air),watershed disturbance,and possibly *** with macrophyte loss,diel dissolved oxygen(DO)and pH variability were reduced,indicating an influence of macrophytes on water quality at an ecosystem *** loss was correlated with declining gross production and respiration,which altered the diel dynamics of pH,DO,and partial pressure of carbon dioxide at some *** certain conditions,there was an association between eelgrass biomass and changes in DO and pH of more than 2 mg/l and 0.3 units,*** found that daytime amelioration of low DO and pH was possible at certain locations when macrophyte biomass(especially eelgrass)was ***,our analyses suggested that the efficacy of macrophyte mitigation of OAH depends on macrophyte abundance and the volume and residence time of overlying water.

关键词： Estuary Northwest estuary

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oregon Manifest设计挑战赛

设计 2011年第11期24卷 26-31页

作者：韩佳成 oregon Manifest

oregon Manifest设计挑战赛近日在波特兰举行，共40件作品参加比赛。oregon Manifest设计挑战赛是一项旨在重新定义日常生活交通方式的设计大赛，以激发设计灵感、创新现代生活所需的自行车为设计目标，得到了全球众多自行车制造商和顶... 详细信息

oregon Manifest设计挑战赛近日在波特兰举行，共40件作品参加比赛。oregon Manifest设计挑战赛是一项旨在重新定义日常生活交通方式的设计大赛，以激发设计灵感、创新现代生活所需的自行车为设计目标，得到了全球众多自行车制造商和顶级设计公司的积极参与。

关键词：设计灵感现代生活交通方式设计目标自行车级设计制造商

Isolation and Identification of Bacterial Endophytes from Grasses along the oregon Coast

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American Journal of Plant Sciences 2017年第3期8卷 574-601页

作者： James E. Dombrowski Vicky G. Hollenbeck Ruth C. Martin USDA ARS Forage Seed and Cereal Research Unit Corvallis Oregon USA

Bacterial endophytes have been shown to improve abiotic and biotic stress responses in plants. Plants growing under harsh conditions along the oregon Coast could contain bacterial endophytes that improve persistence and growth of grasses in this environment. Thirty-four plants consisting of eight different species were collected along the oregon coast from four different sites. Bacterial endophytes were isolated from root crown, stem and leaf tissues. A portion of the 16S rRNA ITS regions of each isolate was amplified, sequenced, and used to perform a BLAST search against the nucleotide database collection at National Center for Biotechnology Information. One-hundred and thirty-three different bacterial isolates, ninety-four of which were unique, representing thirty-six different taxonomic groups were found. Over 50% of the total bacteria isolates were in just five taxonomic groups. Pseudomonads were the most predominant bacteria isolated, making up 20.3% of the total isolates, followed by Curtobacterium and Microbacterium, each at 8.2%, Bacillus at 7.5% and Xanthomomas at 6%. Forty-seven percent (17 of 36) of the taxonomic groups contained only a single isolate. Fourteen bacterial isolates from five taxonomic groups, nine of which were from the genus Pseudomonas, were found to have 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity, an enzyme associated with improving plant growth under stress. These newly discovered bacterial endophytes will be a valuable biological resource to develop approaches to increase the yield and adaptability of grasses and other crops grown in diverse environments and to meet the challenges associated with an unpredictable climate.

关键词： Endophyte Grasses ACC Deaminase Bacteria Abiotic Stress Salt Stress

Characterization of Springtime Coliform Populations at the End Creek Wetland Restoration (Union Co., oregon, USA): A Three-Year Study

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Natural Resources 2015年第8期6卷 482-490页

作者： Joseph A. Corsini Larry Rob Peters Brian Tarpy Chung Pak Karen Antell Eastern oregon University La Grande USA Aquinas College Grand Rapids USA

In 2005, a 550-acre tract of agricultural land containing two small streams near La Grande, oregon was registered in the U.S. Federal Wetlands Reserve Program. This designation was part of a plan to reclaim and restore the wetland to its natural state. Initial efforts at the End Creek Restoration Project restored both End Creek and South Fork Willow Creek to a natural course through rechanneling, and several plantings had restored some of the native flora. Since its establishment, the End Creek streams and floodplain have become a reserve for summer steelhead (Oncorhynchus mykiss), a threatened anadromous salmonid, and many migratory birds. The threatened Columbia Spotted Frog has also established itself in some of the ponds. As part of an effort to establish a baseline for water quality, we monitored total springtime coliform and fecal coliform bacteria in three of the End Creek ponds for three years. The results of this study indicate that, throughout any given spring, the numbers of both coliform and fecal coliform bacteria can fluctuate markedly among ponds on any given day, and that in any particular pond the numbers fluctuate from week to week. In addition, our analysis suggests that in early spring, the numbers of these organisms also fluctuate from year to year. The causes of these fluctuations are not well understood, but are expected to reflect both springtime flooding and the migrations of source animals such as waterfowl and cervids. Information gathered from this study will help inform future management activities on the wetland.

关键词： Coliform Fecal Coliform End Creek Wetland Restoration