Search results for "forest"

Application of deep convolutional neural networks for the detection of anthracnose in olives using VIS/NIR hyperspectral images

2021

Abstract Anthracnose is one of the primary diseases that affect olive production before and after harvest, causing severe damage and economic losses. The objective of this work is to detect this disease in the early stages, using hyperspectral images and advanced modelling techniques of Deep Learning (DL) and convolutional neural networks (CNN). The olives were artificially inoculated with the fungus. Hyperspectral images (450–1050 nm) of each olive were acquired until visual symptoms of the disease were observed, in some cases up to 9 days. The olives were classified into two classes: control, inoculated with water, and fungi composed of olives inoculated with the fungus. The ResNet101 arc…

Nitrous oxide emission by agricultural soils: a review of spatial and temporal variability for mitigation

2012

CT3 ; EnjS4; International audience; This short review deals with soils as an important source of the greenhouse gas N2O. The production and consumption of N2O in soils mainly involve biotic processes: the anaerobic process of denitrification and the aerobic process of nitrification. The factors that significantly influence agricultural N2O emissions mainly concern the agricultural practices (N application rate, crop type, fertilizer type) and soil conditions (soil moisture, soil organic C content, soil pH and texture). Large variability of N2O fluxes is known to occur both at different spatial and temporal scales. Currently new techniques could help to improve the capture of the spatial va…

Estudio crítico de los índices de severidad y la superficie afectada por el incendio de Sierra de Luna (Zaragoza)

2017

[EN] To determine the area burned by fire and its associated severity related to this forest fire taken place in Sierra de Luna (Zaragoza), on July 4th, 2015, three spectral indices derived from Landsat-8 imagery have been calculated: NDVI, NBR and BAI. Comparing the results obtained from each of them, in a wildland fire with extensive crop areas surrounded by forested areas, it has been demonstrated that combination of ΔNBR and BAI substantially improves the calculation of the burned area, concerning both in its external perimeter and in the unburned zones inside of the perimeter. For severity calculation is proposed a new methodology based on before and after NBR differences and its BAI c…

RAVENNA C., 2013 – Circeo. Il parco nazionale, natura, storia, itinerari guidati 183 pp., € 20, Edizioni Belvedere.

2014

Early post-fire bird community in European boreal forest: Comparing salvage-logged with non-intervention areas

2019

Salvage logging after disturbances in forests substantially modifies vegetation structureand dead wood availability, but empirical evidence on its impact on biodiversity, especiallyin European boreal forest, is sparse. In this study we investigated the short-term effect ofpost-fire salvage logging on species richness and abundance of birds in recently burnedmixed coniferous forest. Using point counts we estimated local species composition at 49salvaged sites and 55 non-intervention sites (burnt forest left for natural regeneration) thatwere not logged after afire in south-central Sweden. Local species richness, abundanceand Simpson's species diversity index were significantly higher at non-…

Special Issue: Water Management Strategies in Irrigated Areas

2016

The 2015 edition of the United Nations World Water Development Report highlighted that ‘water is at the core of sustainable development’. Water has upgraded the quality of human life, and any progress to achieve a more sustainable world will deal with the maintenance and/or the improvement of water management. Water demand has grown at more than twice the population rate in the XX century. By 2025, it is estimated that about 1.8 billion people will live in countries or regions with absolute water scarcity, and two-thirds of the world population could be under stress conditions.

Managing a boreal forest landscape for providing timber, storing and sequestering carbon

2015

Human well-being highly depends on ecosystem services and this dependence is expected to increase in the future with increasing population and economic growth. Studies that investigate trade-offs between ecosystem services are urgently needed for informing policy-makers. We examine the trade-offs between a provisioning (revenues from timber selling) and regulating (carbon storage and sequestration) ecosystem services among seven alternative forest management regimes in a large boreal forest production landscape. First, we estimate the potential of the landscape to produce harvest revenues and store/sequester carbon across a 50-year time period. Then, we identify conflicts between harvest re…

Assessment of threat status and management effectiveness in Kakamega Forest, Kenya

2006

To counteract an increasing biodiversity decline, parks and protected areas have been established worldwide. However, many parks lack adequate management to address environmental degradation. To improve management strategies simple tools are needed for an assessment of human impact and management effectiveness of protected areas. This study quantifies the current threats in the heavily fragmented and degraded tropical rainforest of Kakamega, western Kenya. We recorded seven disturbance parameters at 22 sites in differently managed and protected areas of Kakamega Forest. Our data indicate a high level of human impact throughout the forest with illegal logging being most widespread. Furthermo…

Life forms, life strategies and ecological indices of bryophytes for bioindication in wood areas: a case of study in the "Bosco della Ficuzza, Rocca …

2015

Life forms, life strategies and ecological indices of bryophytes which live in evergreen and deciduous Quercus woods as well as in a Pinus halepensis artificial system within the "Bosco della Ficuzza, Rocca Busambra, Bosco del Cappelliere e Gorgo del Drago" Oriented Nature Reserve are analysed and compared. The study highlights that in the same local climatic conditions the Quercus and Pinus trees select different bio-ecological types in the bryophyte communities. They appear to be especially useful to detect physionomic-structural differences in the woods, integrating the information provided by the ecological indices

Woodland key habitats evaluated as part of a functional reserve network

2010

Abstract Woodland key habitats (WKHs) represent a potentially cost-efficient means to protect biodiversity in managed forests. The Forest Act of Finland defines 13 habitat types of WKHs, which enjoy legal protection. It has been argued that WKHs are too small-sized and scattered in occurrence to be actually important in the maintenance of forest biodiversity. However, from the species’ perspective, WKHs form a network together with nature reserves. We evaluated the value and role of WKHs as a part of the whole reserve network using a graph-theoretical connectivity approach in three areas (ca. 500 km 2 each) located in Central Finland. The networks were formed separately for different habita…