Preliminary map showing surficial materials of the Ventura-Oxnard Plain area, California

Abstract During a regular survey of declining forests in 2011, sudden dieback symptoms were observed on scattered wild cherry trees (Prunus avium) in a mixed deciduous forest stand, located in the flood plain area of the Rába River, in northwest Hungary. In this study, we correlated both soil conditions and presence of Phytophthora spp. to dieback of cherry trees. Two Phytophthora species, P. polonica and P. plurivora, were isolated from the rhizosphere soil of the dying trees. By contrast, only P. polonica was recovered from the necrotic tissues of symptomatic roots. Stem and root inoculation tests on cherry seedlings showed pathogenicity of both species, although P. polonica proved to be more virulent. This is the first report of natural infections of P. polonica.

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Effects of Riverbed Extraction on Ground Water Resources in the Vicinity of Tinau River, Rupandehi

Nepal Journal of Science and Technology ◽

10.3126/njst.v13i2.7726 ◽

2013 ◽

Vol 13 (2) ◽

pp. 133-140 ◽

Cited By ~ 2

Author(s):

Khet R Dahal ◽

Chandra P Poudyal ◽

Prajwal Adhikari ◽

Subodh Sharma ◽

Jitendra Ghimire

Keyword(s):

Low Income ◽

Local Governance ◽

Flood Plain ◽

Dry Season ◽

Income Generation ◽

Plain Area ◽

The People ◽

Tube Wells ◽

Medium Level ◽

Dug Well

CORRECTION: The correct PDF for this article was loaded on 22/04/2013.The study was carried out in the vicinity of the Tinau river, Rupandehi, Nepal from July 2011 to June 2012. Ten number of shallow tube wells (STWs) of depths 5.18 m to 7.62 m, four shallow tube wells (STWs) of depths 28.96 m to 36.58 m. from Amawa and Farsatikar Village Development Committees and one dug well (DW) from Butwal Municipality were selected for the purpose of this study. The depth of the STWs was different but many STWs were of 6.09 m deep. The DW was of 18.29 m. The information was collected from the owners during field visit of the sites. A standard questionnaire was prepared and asked to the affected persons. The site observation was done in the dry season as well as in the rainy seasons. It was found that the extraction of riverbed materials from the river channel and the flood plain area has adversely affected the aquatic environment of the Tinau river. Massive extraction of the riverbed materials from this river started after the enforcement of local governance act, and regulation 1999. The income generated from the riverbed materials is quite enough. This is one of the major sources of income generation of DDC Rupandehi and the VDCs attached to this river (from Butwal to Bethari). The depth of the river increased due to extraction activities as a result groundwater table lowered. The STWs having depth of 5.18 to 7.62 m stopped discharging water from the aquifer in the dry season. Similarly DW of Butwal municipality having depth of 18.29 m stopped discharging water at dry season. But the STWs of depths from 28.96 m to 36.58 m. located at the same area/site were not affected by the extraction in the Tinau river. The people, who are residing on the bank of the river Tinau, suffered from drinking water problem because they are using the water from STWs. The effect is directly facing the people of low and medium level having low income generation. The extraction activity is going on and the deficit of water availability in STWs and DW is common in the vicinity of the Tinau river especially in the upstream (from Butwal to Paschim Amawa), whereas there is less effects of riverbed extraction for STWs of depths more than 27.43 m in the same sites. Nepal Journal of Science and Technology Vol. 13, No. 2 (2012) 133-140 DOI: http://dx.doi.org/10.3126/njst.v13i2.7726

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Groundwater vulnerability assessment: from overlay methods to statistical methods in the Lombardy Plain area

Acque Sotterranee-Italian Journal of Groundwater ◽

10.7343/as-2017-276 ◽

2017 ◽

Vol 6 (2) ◽

Cited By ~ 4

Author(s):

Stefania Stevenazzi ◽

Marco Masetti ◽

Giovanni Pietro Beretta

Keyword(s):

Land Use Planning ◽

Vulnerability Assessment ◽

Industrial Development ◽

Regional Scale ◽

Scientific Progress ◽

Groundwater Vulnerability ◽

Anthropogenic Sources ◽

Plain Area ◽

Groundwater Vulnerability Assessment ◽

Vulnerability Maps

Groundwater is among the most important freshwater resources. Worldwide, aquifers are experiencing an increasing threat of pollution from urbanization, industrial development, agricultural activities and mining enterprise. Thus, practical actions, strategies and solutions to protect groundwater from these anthropogenic sources are widely required. The most efficient tool, which helps supporting land use planning, while protecting groundwater from contamination, is represented by groundwater vulnerability assessment. Over the years, several methods assessing groundwater vulnerability have been developed: overlay and index methods, statistical and process-based methods. All methods are means to synthesize complex hydrogeological information into a unique document, which is a groundwater vulnerability map, useable by planners, decision and policy makers, geoscientists and the public. Although it is not possible to identify an approach which could be the best one for all situations, the final product should always be scientific defensible, meaningful and reliable. Nevertheless, various methods may produce very different results at any given site. Thus, reasons for similarities and differences need to be deeply investigated. This study demonstrates the reliability and flexibility of a spatial statistical method to assess groundwater vulnerability to contamination at a regional scale. The Lombardy Plain case study is particularly interesting for its long history of groundwater monitoring (quality and quantity), availability of hydrogeological data, and combined presence of various anthropogenic sources of contamination. Recent updates of the regional water protection plan have raised the necessity of realizing more flexible, reliable and accurate groundwater vulnerability maps. A comparison of groundwater vulnerability maps obtained through different approaches and developed in a time span of several years has demonstrated the relevance of the continuous scientific progress, recognizing strengths and weaknesses of each research.

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