Search results for "Forestry"
showing 10 items of 1998 documents
Wood-decaying fungi in old-growth boreal forest fragments: extinctions and colonizations over 20 years
2021
According to ecology theory, isolated habitat fragments cannot maintain populations of specialized species. Yet, empirical evidence based on monitoring of the same fragments over time is still limited. We studied the colonizationâextinction dynamics of eight wood-decaying fungal species in 16 old-growth forest fragments (<14 ha) over a 20-year period (1997â2017). We observed 19 extinctions and 5 colonizations; yet, the distribution of extinctions and colonizations did not differ from the one expected by chance for any of the species. Twenty-six percent of the extinctions took place in two natural fragments amid large forestâpeatland complexes. (Romell) Bourdot and Galzin decreased …
A survey of carbon sequestration potential of orchards and vineyards in Italy
2016
Orchards and vineyards are important land use types in Southern Europe. In spite of their potential to sequester atmospheric C and to mitigate climate change, relatively little is known regarding the influx and outflux of C in these systems. The aim of this work is to provide data on the C budget, including net primary production (NPP), C removal through production, and C sequestration potential for the vineyards and the main fruit tree species (apple, citrus, olive, and peach) grown in Italy. Standing biomass and NPP were measured, and net ecosystem exchange and net C balance assessed directly, through either eddy covariance technique, or considering NPP and heterotrophic respiration. Abov…
Arbuscular mycorrhizal fungi in Georgia, the Caucasus region: the first report of species diversity and root colonization
2018
Although the Caucasus region belongs to the world biodiversity hotspots, arbuscular mycorrhizal fungi (AMF) have not been investigated in this area. A total of 11 mixtures of soils and roots from 11 localities in southern Georgia in an altitudinal gradient from 1 to 1560 m a. s. l. were sampled in 2015. AMF spores and arbuscular mycorrhiza were observed in all samples. Eight AMF species were found in the field-collected soils: Acaulospora bireticulata, Acaulospora cavernata, Funneliformis coronatum, Gigaspora gigantea, Glomus rubiforme, Scutellospora dipurpurescens, Septoglomus constrictum, and Septoglomus jasnowskae. The most frequently occurring species proved to be S. constrictum. Labora…
The effects of different combinations of fixed and moving bed bioreactors on rainbow trout (Oncorhynchus mykiss) growth and health, water quality and…
2019
Abstract The effect of bioreactor design on nitrification efficiency has been well studied, but less is known about the overall impacts on water quality. Besides nitrification, submerged fixed bed bioreactors (FBBR) trap fine solid particles, whereas moving bed bioreactors (MBBR) grind solids, possibly increasing solids and particle accumulation in the system. In this experiment, the effects of different combinations of fixed bed and moving bed bioreactors on water quality, solids removal, particle size distribution, fish health based on histopathological changes and nitrification efficiency were studied in laboratory scale recirculating aquaculture systems (RAS) with rainbow trout (Oncorhy…
Environmental Modelling of Forest Vegetation Zones as A Support Tool for Sustainable Management of Central European Spruce Forests
2018
Abstract The impact of climate change on forest ecosystems may manifest itself by a shift in forest vegetation zones in the landscape northward and into higher elevations. Studies of climate change-induced vegetation zone shifts in forest ecosystems have been relatively rare in the context of European temperate zone (apart from Alpine regions). The presented paper outlines the results of a biogeographic model of climatic conditions in forest vegetation zones applied in the Central European landscape. The objective of the study is a prediction of future silvicultural conditions for the Norway spruce (Picea abies L. Karst.), which is one of the principal tree species within European forests. …
Ascaridoid nematodes in horse mackerel, Trachurus trachurus, sold in Spanish supermarkets—Factors able to diminish consumer risk
2020
Abstract Horse mackerel, Trachurus trachurus, specimens sold in supermarket chains in the metropolitan area of Valencia (Spain) were analyzed to assess which intrinsic and extrinsic factors are able to diminish the risk of human anisakiosis. 202 T. trachurus, caught in the Atlantic Ocean and the Mediterranean Sea, were examined for ascaridoid nematodes. The overall prevalence and abundance of Anisakis type I larvae were 65.3 % and 23.2 helminths/host, respectively, being higher in the Atlantic area (98.2 %; 41.4 helminths/host). 34.2 % of the total fish sample was parasitized in the flesh. Moreover, global prevalence and abundance of Hysterothylacium spp. larvae were 67.3 % and 9.41, respec…
Marginal fragmented beech stands and climate change in Sicily: effects of non-sustainable traditional silviculture practices in relation to micro-top…
2016
In Sicily where the southernmost beech forests of Europe are located, beech stands show peculiar ecological, characters. The ecological marginality of these forests is particularly evident in the fragmented and isolated beech stands, near the timberline and/or located on less favourable topographic conditions. In this study we analyzed stand-structural parameters and tree health comparing recently coppice felled beech stands and control plots. Additionally, these aspects have been related also to the local topographic gradient and the cover fragmentation. Results clearly show a pronounced tree health reduction (more crown and bark damages, higher percentage of dead trees, lower seedling den…
Some effects of the herbicide EL-107 on cellular growth and metabolism
1987
Summary Effects of the herbicide EL-107 (N-[3-(1-ethyl-1-methylpropyl)-5-isoxazolyl]-2,6-dimethoxy-benzamide) on the growth of dicotyledonous plants are described. The herbicide did not inhibit germination but reduced the growth of rape (Brassica napus L.) by half at 0.0057 mg l−1. The most characteristic symptom induced was a swelling of the apical regions, and histological observations of root tips of Polygonum persicaria and rape revealed a progressve disappearance of the meristematic zone, which was replaced by enlarged cells almost devoid of cytoplasm. Growth of cells of Acer pseudoplatanus L. and soybean (Glycine max L.) cultured in suspension was also inhibited by EL-107, which induc…
Hybrids and allied species as potential rootstocks for eggplant: Effect of grafting on vigour, yield and overall fruit quality traits
2018
Abstract Grafting of fruiting vegetables is an effective technique to overcome pests and diseases in modern cropping systems and it is often used to improve yield and fruit quality. Eggplant is an important vegetable crop that benefits significantly from grafting. In this regards, the exploitation, valorization and breeding of new rootstock genotypes as possible substitute to those commonly used (Solanum torvum and tomato hybrids) would permit an intensive eggplant crop system in those situations where a rootstock rotation is required. In the present article, we study the effects of several potential rootstocks including both wild/allied species of eggplant [S. torvum (STO), S. macrocarpon …
Evaluating field-scale sampling methods for the estimation of mean plant densities of weeds
2000
The weed flora (comprising seven species) of a field continuously grown with soyabean was simulated for 4 years, using semivariograms established from previous field observations. Various sampling methods were applied and compared for accurately estimating mean plant densities, for differing weed species and years. The tested methods were based on (a) random selection wherein samples were chosen either entirely randomly, randomly with at least 10 or 20 m between samples, or randomly after stratifying the field; (b) systematic selection where samples were placed along diagonals or along zig-zagged lines across the field; (c) predicted Setaria viridis (L.) P. Beaux seedling maps which were us…