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111.
Development of a framework for fire risk assessment using remote sensing and geographic information system technologies 总被引:10,自引:0,他引:10
Emilio Chuvieco Inmaculada Aguado Héctor Nieto M. Pilar Martín Lara Vilar Susana Martín Juan de la Riva Francisco Rodríguez Miguel A. Herrera 《Ecological modelling》2010,221(1):46-58
Forest fires play a critical role in landscape transformation, vegetation succession, soil degradation and air quality. Improvements in fire risk estimation are vital to reduce the negative impacts of fire, either by lessen burn severity or intensity through fuel management, or by aiding the natural vegetation recovery using post-fire treatments. This paper presents the methods to generate the input variables and the risk integration developed within the Firemap project (funded under the Spanish Ministry of Science and Technology) to map wildland fire risk for several regions of Spain. After defining the conceptual scheme for fire risk assessment, the paper describes the methods used to generate the risk parameters, and presents proposals for their integration into synthetic risk indices. The generation of the input variables was based on an extensive use of geographic information system and remote sensing technologies, since the project was intended to provide a spatial and temporal assessment of risk conditions. All variables were mapped at 1 km2 spatial resolution, and were integrated into a web-mapping service system. This service was active in the summer of 2007 for semi-operational testing of end-users. The paper also presents the first validation results of the danger index, by comparing temporal trends of different danger components and fire occurrence in the different study regions. 相似文献
112.
The high incidence of hunting activity and forest fires in different ecosystems (particularly in Mediterranean ecosystems) requires a model, which allows for the comprehensive management of hunting resources and estimating the potential damage caused by this type of disturbance. This paper proposes a model for evaluating the socio-economic effects of forest fires on hunting. Its cornerstone lies in evaluating hunting resource availability for each ecosystem within its territorial mosaic. Each game management unit (GMU) is identified by vegetation structure and habitat type. It presents a novel approach in which the economic value of each game management unit is linked to potential forest fire damages. The effect a forest fire has on an entire ecosystem depends on the intensity of its flames. A sample study was undertaken in the province of Huelva in Andalusia (southern Spain). The socio-economic hunting vulnerability of the province of Huelva was 45,188,000€. The results obtained confirmed the need for an economic appraisal of non-forest products in the forest and other woodland areas. Geographic Information System increases the flexibility and simplicity of our methodology which permits immediate extrapolation to other agroforestry territories. 相似文献
113.
Sapucci Gabriela Ribeiro Negri Rogério Galante Casaca Wallace Massi Klécia Gili 《Environmental Modeling and Assessment》2021,26(4):581-590
Environmental Modeling & Assessment - Over the past decades, the Southeast Atlantic Forest in Paraíba do Sul River Valley has suffered intense deforestation and human disturbances. Due to... 相似文献
114.
Life-history variation was studied in three sympatric species of Stylopoma Levinsen [S. spongites (Pallas), S. projecta Canu and Bassler and Stylopoma n. sp. 15] in Panamá. Bryozoan colonies were collected from 27 reefs along 300 km of the Caribbean coast of Panamá. The distribution and abundance of each species were very patchy, but with broad overlap in occurrence among localities and depths. Nevertheless, species differed considerably in colony size, size at first reproduction and numbers of brooding larvae; implying that interspecific differences in life-history traits may contribute to their coexistence. To examine closely this variation in life-history patterns, we grew, in a common garden experiment, the offspring of the two most common species that were obtained from parent colonies collected from several reefs. There were highly significant differences in growth rates and the timing and extent of sexual reproduction which corresponded well to patterns observed in individuals from the field. Other factors, including size of larvae, extent of secondary zooidal calcification and numbers of avicularia were also correlated with differences in life histories. Despite this additional complexity, however, ecological consequences of trade-offs in life history among modular species such as Stylopoma spp. appear very similar to those among unitary species. 相似文献
115.
Highly concentrated phenolic wastewater treatment by the photo-Fenton reaction, mechanism study by FTIR-ATR 总被引:3,自引:0,他引:3
Araña J Tello Rendón E Doña Rodríguez JM Herrera Melián JA González Díaz O Pérez Peña J 《Chemosphere》2001,44(5):1017-1023
Phenol degradation by Photo-Fenton reaction has been studied in highly concentrated wastewaters and most intermediate species have been identified by Fourier Transform IR-Spectroscopy with ATR device. During the photodegradation of highly concentrated phenol solutions, the formation of dissolved and precipitate tannin has been observed. The possibility of a Fe3+-Pyrogallol complex formation, previous to the tannin formation, has been proposed too. The complex formation involving Fe3+ ions could be related to the observed Photo-Fenton activity decrease. Tannin formation inhibits the complete mineralization of phenol because *OH radicals attack will produce further condensation steps and the polymer size increase. This fact limits the applicability of the process for highly concentrated phenolic wastes mineralization. However, the tannin precipitation allows its separation from the solution by conventional filtration, and reduction of the corresponding dissolved organic carbon. These observations have been proved from the identification of primary degradation products, catechol and hydroquinone. Catechol is considered to be the first step for the formation of tannins. Degradation process for phenol, catechol and hydroquinone have been monitored by total organic carbon (TOC) measurements along the reaction time span. From these results, a global mechanism for the Photo-Fenton degradation of phenol is proposed. 相似文献
116.
Current evolution of wireless personal communications has necessitated a comprehensive understanding of electromagnetic interactions
between handset antennas and nearby human body. In this work the handset–human body interactions were evaluated in various
configurations (with and without user’s hand; with and without user’s head, and combinations of them) in order to obtain statistical
averages of the overall performance for system link evaluations. The measurements were performed using the random-field measurement
(RFM) method, and thus the acquisition of large amounts of data about human–mobile phone interactions in typical operating
environment with measured the received RF signal strength (RXLEV), and the output power level (TXLEV) on mobile station. The
RXLEV and the TXLEV was measured over the air interface in the networks on two Bulgarian GSM mobile operators (Mtel and Vivatel).
Both uplink and downlink measurements were performed in urban area in three cities. Each measurements were carried out in
a building included both line-of-sight and non-line-of-sight propagation of the electromagnetic waves between mobile station
and base station. The results showed that the user’s hand and head induces more significant changes on the received RF signal
strength in case when broadcast control channel (BCCH) levels are up to −60 dBm. Also the alterations of receiving RF signal
strength and output power level of the MS are influence stronger from the larger size of the hand and head of user. The influence
from presence of the head and hand of the subscriber in talk position over the alteration of the receiving RF signal strength
is in boundaries from 14.21 dBm to 19.1 dBm (man) and from 8.5 dBm to 12.05 dBm (woman). The presence of the user’s hand and
head increased the output power level of mobile station with 12 dBm to 14 dBm (man) and with 10 dBm to 12 dBm (woman) compare
to output power level without user’s hand and head. 相似文献
117.
Civeira Gabriela Lado Liares Marcos Vidal Vazquez Eva Paz Gonzlez Antonio 《Environmental management》2020,65(3):355-368
Environmental Management - This work quantified ecosystem services (ES) and the geographic gross product (GGP) at municipal level in the Metropolitan Region of Buenos Aires (MRBA), Argentina. The... 相似文献
118.
Matache ML David IG Matache M Ropota M 《Environmental monitoring and assessment》2009,153(1-4):273-279
Sampling streams for metals is an important aspect of water-quality monitoring. Using ICP-AES the concentration of some microelements in the Ialomi?a River (Romania) were determined. In order to grasp the different phases of the river regime, samples were collected from its water-sediment interface at seven locations along the river, during three campaigns: during snow melting periods in the mountain zones (April), the period of reduced flow and high water temperature (August) and the period of high precipitations (November). HNO3 was added to the samples for fixation. Cadmium and copper appear accidentally; lead was detected only in samples collected in the vicinity of roads; the MAC (maximum admitted concentration) for surface waters is exceeded for nickel and chromium in samples collected in April and respectively in April and November; zinc concentrations were usually above the MAC; molybdenum concentration was above the set reference value, especially for samples collected in April and November. Possible explanations are given for the presence of the investigated microelements along the river. 相似文献
119.
Bulgaroni V Rovedatti MG Sabino G Magnarelli G 《Environmental monitoring and assessment》2012,184(5):3307-3314
A pilot study was conducted to evaluate the usefulness of salivary cholinesterase and carboxylesterase as biomarkers of exposure
to environmental organophosphate pesticides. Ninety samples were obtained from women and 62 samples from their preschool-aged
children who live near an agricultural area of the Upper Valley of the Negro River (Patagonia, Argentina) where pesticides
are applied 6 months a year. Each participant donated two samples under similar conditions: one in the pre-exposure period
and another during the pulverization period. Demographic information, potential confounders, and risk behaviors were registered.
Active or passive smoking had no effect on these enzyme activities in either group. During the pulverization period, cholinesterase
activity was not detectable in 76% of the children's samples and 23% of the mothers' samples. Comparing samples collected
during the pulverization period with respect to the pre-pulverization period, the average mother and child cholinesterase
activity decreased by 65.7% (p < 0.001) and 85.8% (p < 0.001), respectively. Also, mother and child carboxylesterase activity decreased by 27.5% (p < 0.001) and 41.9% (p < 0.01), respectively. Child carboxylesterase activity in the pulverization period was associated to the habit of eating
dust outdoors (p < 0.01). The most frequent inhibition levels observed for cholinesterase and carboxylesterase activity were between 70–100%
and 0–29%, respectively, in both groups studied. This shows that at the same level of exposure, cholinesterase was more sensitive
to inhibition than carboxylesterase. Therefore, carboxylesterase might more properly reflect the degree of environmental organophosphate
exposure and may have potential as a novel tool for biomonitoring. 相似文献
120.
Ambient levels of carbonyl compounds and their possible sources were studied at three places in the metropolitan area of Costa
Rica, including a residential, an industrial, and a commercial downtown area with high vehicular flow, during the periods
of April–May and September–December 2009. Fifteen carbonyl compounds were identified in the ambient air, of which acetone
was the most abundant carbonyl, followed by formaldehyde and acetaldehyde. Concentrations were highest in rainy season at
all sites and lower in dry season. These decreases in concentration are explained by the influences of both photochemical
reactions and local meteorological conditions. The strong correlation between C1–C2 and C3 indicated a common origin for these
carbonyls. The C1/C2 ratios varied between 0.49 to 1.05, values which can be considered typical of an urban area. 相似文献