Search results for "flooding"
showing 10 items of 64 documents
Mapping temporally-variable exposure to flooding in small Mediterranean basins using land-use indicators
2011
Abstract This article deals with mapping exposure (or external vulnerability) to flood risk in two typical Mediterranean ephemeral streams: the Barranco de Carraixet and the Rambla de Poyo. The floodplains of both streams are within the metropolitan area of the city of Valencia (Spain’s third largest city). Following the Mediterranean model, they are very fertile areas (with intense periurban and highly productive agriculture) which have recently absorbed the great urban expansion of the metropolis. Hydrologically these basins remain dry for most of the year, but become particularly dangerous during flash-flood events. They generate a risk pattern highly dependent on exposure since, in gene…
Long-Term Hydrological Regime Monitoring of a Mediterranean Agro-Ecological Wetland Using Landsat Imagery: Correlation with the Water Renewal Rate of…
2021
The Natural Park of Albufera (Valencia, Spain) is one of the Spanish Mediterranean wetlands where rice is cultivated intensively. The hydrology of the Albufera Lake, located in the center, combines natural contributions with complex human management. The aim of our study was to develop a new methodology to accurately detect the volume of flood water in complex natural environments which experience significant seasonal changes due to climate and agriculture. The study included 132 Landsat images, covering a 15-year period. The algorithm was adjusted using the NDWI index and simultaneous measurements of water levels in the rice fields. The NDVI index was applied to monitor the cultivated area…
Metro Manila's challenges: flooding, housing and mobility
2014
International audience
The Stationarity of Lead-Lag Teleconnections with East Africa Rainfall and its Incidence on Seasonal Predictability
2001
East Africa experiences large interannual rainfall variations, which can lead to severe droughts, as in 1984 in Ethiopia, or extensive flooding, as in 1997 in Somalia and Kenya. In the last 15 years, significant advances have been made in relating these variations to large-scale ocean-atmosphere anomalies, of which those associated to ENSO (El Nino Southern Oscillation) come first. The additional importance of sea-surface variations in the Tropical Atlantic and Indian Oceans is becoming established. Although 20th century East African precipitation series did not experience decadal-scale trends as significant as those found in the sahelian belt, the correlation with ENSO, the Indian monsoon …
Evaluation and improvement of collective flooding in WSNs with various link correlations
2015
One of the main challenges confronted by wireless sensor networks (WSNs) is to reduce energy consumption of nodes for the purpose of network lifetime extension. In the literature, many backbone based protocols such as connected dominating set (CDS) and broadcast or multicast based protocols are employed in order to improve network performance in terms of metrics like energy consumption, number of transmissions and dissemination delay. In this paper, we evaluate the performance of a recently proposed transmission protocol known as collective flooding (CF), which is based on link correlation, under various link correlation conditions. Through simulations and analyses we demonstrate that altho…
Assessing and mapping multi-hazard risk susceptibility using a machine learning technique
2020
AbstractThe aim of the current study was to suggest a multi-hazard probability assessment in Fars Province, Shiraz City, and its four strategic watersheds. At first, we construct maps depicting the most effective factors on floods (12 factors), forest fires (10 factors), and landslides (10 factors), and used the Boruta algorithm to prioritize the impact of each respective factor on the occurrence of each hazard. Subsequently, flood, landslides, and forest fire susceptibility maps prepared using a Random Forest (RF) model in the R statistical software. Results indicate that 42.83% of the study area are not susceptible to any hazards, while 2.67% of the area is at risk of all three hazards. T…
Notice of Violation of IEEE Publication Principles<BR>An adaptive routing mechanism for P2P resource discovery
2005
The key to the usability of large-scale decentralize peer-to-peer (P2P) systems, and one of the most challenge design aspects, is efficient mechanism for distributed resource discovery. Unstructured P2P networks are very attractive because they do not suffer the limitations of centralized systems an the drawbacks of highly structured approaches. However the search algorithms are usually based on simple flooding scheme generating large loads on the network participants. In this paper to address this major limitation, we present the design an evaluation of an innovative searching protocol in unstructured P2P networks. The approach aims at dynamically adapting the network topology to peers' in…
Selection of the Optimal Design Rainfall Return Period of Urban Drainage Systems
2014
Abstract The aim of this work is to define a methodology to identify the optimal rainfall return period for the design of urban drainage systems. The choice of the optimal return period is made minimizing the total costs of the system: the sewer network is dimensioned for a set of possible design rainfall return periods, and the corresponding construction, maintenance and operation costs are evaluated. For each scenario, the total expected damage from flooding caused by rainfall events with return period greater than the design one is then estimated by hydraulic simulation. This methodology has been applied to a small urban catchment in Palermo (Italy).
Lotus spp: biotechnological strategies to improve the bioeconomy of lowlands in the Salado River Basin (Argentina)
2016
The Salado River Basin region is the most important livestock breeding area in Argentina, wherethe Lotus species has been traditionally cultivated as forages. Nearly 60% of their land surface is dominated by salt-affected soils with severe constraints for crop cultivation. In order to cope with that limitation, farmers have utilized species such as non-native L. tenuis (ex- Lotus glaber), which shows a very good adaptation. As a result, inter-seeding of L. tenuis has been proposed as a strategy of choice for improving forage production in marginal areas. The increase in soil quality by these means is achieved by an increment of the organic matter content, improvement of soil fertility as we…
A new method to simulate the hydrological state of soil under natural conditions
2009
As micro, macro e mesofaunas no solo respondem frequentemente a variacao das condicoes ambientais, o que resulta em alteracoes na abundância e na estrutura da comunidade. Os efeitos das alteracoes nos parâmetros do solo sao normalmente determinados com amostras recolhidas no campo e trazidas ao laboratorio, ou seja, onde as condicoes ambientais naturais podem nao ser aplicaveis. Criamos um metodo (STAFD - tubos de amostra de solo para inundacoes e secas artificiais), que simula o estado hidrologico do solo in situ com nucleos implantados. As amostras de controle foram comparadas com amostras de tratamentos em que foram simuladas inundacoes de 15, 30, 60 e 90 dias e secas de 60, 90 e 120 dia…