ATRAZINE IN SPRING RUNOFF AS RELATED TO ENVIRONMENTAL SETTING EBRASKA, 1992

Abstract This study compares methods to incorporate climate information into the National Weather Service River Forecast System (NWSRFS). Three small-to-medium river subbasins following roughly along a longitude in the Colorado River basin with different El Niño–Southern Oscillation signals were chosen as test basins. Historical ensemble forecasts of the spring runoff for each basin were generated using modeled hydrologic states and historical precipitation and temperature observations using the Ensemble Streamflow Prediction (ESP) component of the NWSRFS. Two general methods for using a climate index (e.g., Niño-3.4) are presented. The first method, post-ESP, uses the climate index to weight ensemble members from ESP. Four different post-ESP weighting schemes are presented. The second method, preadjustment, uses the climate index to modify the temperature and precipitation ensembles used in ESP. Two preadjustment methods are presented. This study shows the distance-sensitive nearest-neighbor post-ESP to be superior to the other post-ESP weighting schemes. Further, for the basins studied, forecasts based on post-ESP techniques outperformed those based on preadjustment techniques.

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Conjugative plasmids: vessels of the communal gene pool

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2009.0037 ◽

2009 ◽

Vol 364 (1527) ◽

pp. 2275-2289 ◽

Cited By ~ 244

Author(s):

Anders Norman ◽

Lars H. Hansen ◽

Søren J. Sørensen

Keyword(s):

Gene Transfer ◽

Horizontal Gene Transfer ◽

Significant Contribution ◽

Prokaryotic Genome ◽

Whole Genome ◽

Adaptive Traits ◽

Conjugative Plasmids ◽

Environmental Setting ◽

Genome Analyses ◽

Insight Into

Comparative whole-genome analyses have demonstrated that horizontal gene transfer (HGT) provides a significant contribution to prokaryotic genome innovation. The evolution of specific prokaryotes is therefore tightly linked to the environment in which they live and the communal pool of genes available within that environment. Here we use the term supergenome to describe the set of all genes that a prokaryotic ‘individual’ can draw on within a particular environmental setting. Conjugative plasmids can be considered particularly successful entities within the communal pool, which have enabled HGT over large taxonomic distances. These plasmids are collections of discrete regions of genes that function as ‘backbone modules’ to undertake different aspects of overall plasmid maintenance and propagation. Conjugative plasmids often carry suites of ‘accessory elements’ that contribute adaptive traits to the hosts and, potentially, other resident prokaryotes within specific environmental niches. Insight into the evolution of plasmid modules therefore contributes to our knowledge of gene dissemination and evolution within prokaryotic communities. This communal pool provides the prokaryotes with an important mechanistic framework for obtaining adaptability and functional diversity that alleviates the need for large genomes of specialized ‘private genes’.

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Relation of fall stream-flow to spring runoff

Transactions American Geophysical Union ◽

10.1029/tr020i001p00117 ◽

1939 ◽

Vol 20 (1) ◽

pp. 117 ◽

Cited By ~ 2

Author(s):

Henry C. Eagle

Keyword(s):

Stream Flow ◽

Spring Runoff

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Fresh contact: Youth, migration, and atmospheres in India

Environment and Planning D Society and Space ◽

10.1177/0263775818816318 ◽

2018 ◽

Vol 37 (2) ◽

pp. 313-330 ◽

Cited By ~ 2

Author(s):

Jane Dyson

Keyword(s):

Young People ◽

Word Meaning ◽

Local Environment ◽

Social Nature ◽

Environmental Setting ◽

The Social ◽

Youth Agency ◽

Indian Village ◽

High Degree

This paper uses long-term research in an Indian village to develop Karl Mannheim’s notion of each generation’s ‘fresh contact’ with their inherited social and environmental setting. I examine how a generation of young people re-apprehend their local environment following a period of migration. I argue that young people aged between 25 and 34 who have lived outside their locality re-appraise their village economically and spiritually when they return home. I point to the social nature of this ‘fresh contact’, its spatial character, and the high degree of reflexivity that young men display in discussing their own agency as a generation – a point that emerged especially clearly in their discussion of the term ‘ mahaul,’ a Hindi word meaning ‘atmosphere’. The paper contributes to geographical and anthropological work on youth agency by highlighting the utility of notions of fresh contact in specific social conjunctures, such as the migration of a particular cohort. At the same time, it suggests the importance of placing alongside Mannheim’s work an explicit focus on the spatial nature of fresh contact, the sociality that constitutes cohorts as generations, and young people’s reflexive capacity to theorise their generational agency.

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