Search results for "forest"
showing 10 items of 3780 documents
Loci classici, taxa critici e monumenti arborei della flora d'Italia
2011
Impact of land-use type and harvesting on population structure of a non-timber forest product-providing tree in a semi-arid savanna, West Africa
2011
Non-timber forest products (NTFPs) strongly contribute to livelihood security in the semi-arid tropics. Main factors determining the populations of NTFP-providing species are human activities. This study examined the impact of land-use, combined with rates and patterns of debarking and chopping on a NTFP-providing tree (Anogeissus leiocarpa) in Burkina Faso. We compared stands in a protected area (W National Park) with those of its surrounding communal area (fallows, croplands) in order to (i) obtain an indication on the status of the population, (ii) assess its harvesting tolerance, (iii) estimate the sustainability of present management, and (iv) derive which additional management strateg…
Statistical modelling of non-stationary processes of atmospheric pollution from natural sources: example of birch pollen
2016
Abstract A statistical model for predicting daily mean pollen concentrations during the flowering season is constructed and its parameterization and application to birch pollen in Riga (Latvia) are discussed. The model involves several steps of transformations of both meteorological data and pollen observations, aiming at a normally distributed homogeneous stationary dataset with linearized dependencies between the transformed meteorological predictors and pollen concentrations. The data transformation includes normalization of daily mean birch pollen concentrations, a switch of the independent axis from time to heat sum, a projection of governing parameters to pollen concentrations, and a …
Alternative nursery propagation for vineyards establishment
2016
Dead vines are often a problem present in many vineyards and are due to physiological or pathological causes whereby the vines need to be replaced. The aim of the trial was to create in the nursery plant material of four cultivars in order to easily replace the dead vines in the vineyards but also to anticipate the first harvest and to improve the vineyard uniformity and synchronize the vineyard management practices during the first two years of plantation. During the first year in the nursery, the effect of plant density on the percentage of success and vegetative growth was evaluated. During the second year, in the open field and only for one cultivar, the vegetative and reproductive para…
Will nutrient cycles in a tropical montane forest in Ecuador be affected by a changing element composition of rainfall?
2009
Organic Fertilization in Traditional Mediterranean Grapevine Orchards Mediates Changes in Soil Microbial Community Structure and Enhances Soil Fertil…
2016
Soil microbial populations and their functions related to nutrient cycling contribute substantially to the regulation of soil fertility and the sustainability of agroecosystems. A field experiment was performed to assess the medium-term effect of a mineral fertilizer and two organic fertilization systems with different nitrogen sources on the soil microbial community biomass, structure, and composition (phospholipid fatty acids, pattern, and abundance), microbial activity (basal respiration, dehydrogenase, protease, urease, β-glucosidase, and total amount of phosphomonoesterase activities), and physical (aggregate stability) and chemical (total organic C, total N, available P and water-solu…
Macrofungi as ecosystem resources: Conservation versus exploitation
2013
Fungi are organisms of significant importance not only for the crucial roles they undertake in nature but also for many human activities that are strictly dependent on them. Indeed, fungi possess fundamental positions in ecosystems functioning including nutrient cycles and wood decomposition. As concerns human-related activities, edible and non-edible mushrooms are also involved and/or exploited in forestry, pharmaceutical industry and food production; hence, nowadays they represent a major economic source worldwide. In order to maintain and improve their strategic importance, several conservation strategies, such as habitat preservation, are needed. This article reports several contributio…
Soil-Water Interactions Unveiled by Fast Field Cycling NMR Relaxometry
2017
Leaf life span and the mobility of "non-mobile" mineral nutrients - The case of boron in conifers
2002
Nutrient conservation is considered important for the adaptation of plants to infertile environments. The importance of leaf life spans in controlling mean residence time of nutrients in plants has usually been analyzed in relation to nutrients that can be retranslocated within the plant. Longer leaf life spans increase the mean residence time of all mineral nutrients, but for non-mobile nutrients long leaf life spans concurrently cause concentrations in tissues to increase with leaf age, and consequently may reduce non-mobile nutrient use efficiency. Here we analyze how the role of leaf life span is related to the mobility of nutrients within the plant. We use optimality concepts to derive…
Assessing AQUACROP water stress function to evaluate the transpiration reductions of olive tree.
2012
Quantitative evaluation of the drought adaptation processes of crops is an important prerequisite for efficient irrigation management. Modeling the plant response under water stress conditions is crucial to identify the exact irrigation timing. Assessment of any water stress function requires the knowledge of its shape and then the estimation of critical thresholds of the soil water status, below which a strong reduction of plant transpiration occurs. In this work, the macroscopic approach is used to assess the water stress function implemented in AQUACROP for mature olive tree. In particular, after discussing about the function shape, the critical thresholds of soil water status are propos…