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931.
The ecological value of some fine-scale landscape elements tends to be overlooked when they are found in highly human-influenced landscapes, such as peri-urban agricultural ones. These landscapes usually fall beyond the scope of the defined categories of landscape protection, and are thus mapped as areas of little or no ecological interest in the context of extensive analysis. In this paper, we present a method for assessing and visualizing the existing nodes in the field pattern of a peri-urban agricultural landscape. Nodes are identified from the field pattern and characterized according to the presence of relevant features and land uses from the viewpoint of their ecological functions. The method is applied in the Vega del Guadalfeo (south of Spain). Our results show an innovative map of the Vega which may be interpreted as its eco-structure; a model based on nodes to represent the ecological value of the peri-urban agricultural landscape.  相似文献   
932.
Composting is a method for preparing organic fertilizers that represents a suitable management option for the recycling of two-phase olive mill waste (TPOMW) in agriculture. Four different composts were prepared by mixing TPOMW with different agro-industrial by-products (olive pruning, sheep manure and horse manure), which were used either as bulking agents or as N sources. The mature composts were added during six consecutive years to a typical “Picual” olive tree grove in the Jaén province (Spain). The effects of compost addition on soil characteristics, crop yield and nutritional status and also the quality of the olive oil were evaluated at the end of the experiment and compared to a control treated only with mineral fertilization. The most important effects on soil characteristics included a significant increase in the availability of N, P, K and an increase of soil organic matter content. The application of TPOMW compost produced a significant increase in olive oil content in the fruit. The compost amended plots had a 15% higher olive oil content than those treatment with inorganic fertilization. These organics amendments maintained the composition and quality of the olive oil.  相似文献   
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934.
Environmental Science and Pollution Research - The biomass control potential of three metabolic uncouplers (carbonyl cyanide-p-trifluoromethoxyphenylhydrazone (FCCP), carbonyl cyanide...  相似文献   
935.
Hydrodynamic and water quality data has been recorded since February 2014 by a meteo-oceanographic station installed in the inner part of the Gulf of Taranto, in the northeastern part of the Ionian Sea (Southern Italy). This monitoring action, managed by the research unit of the Technical University of Bari, DICATECh Department, could play a pivotal role in a vulnerable and sensitive area, affected by massive chemical and biological pollutant discharges due to the presence of heavy industry and intense maritime traffic. Monthly trends of winds, waves, currents, and biochemical parameters, such as dissolved oxygen, chlorophyll, and turbidity, are analyzed and discussed. The analysis exhibits that the wave regime is slightly controlled by wind forcing; rather, topography strongly affects the wave propagation direction. Surface currents appear wind induced in the measuring station, while near the bottom a quasi-steady current directed towards southwest is formed. The selected water quality indicators show monthly trends consistent with the typical seasonal convective fluxes and mixing.  相似文献   
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939.
The re-use of faecal pellets in the water column before sinking to the seafloor is known as an important pathway in marine food webs. Especially planktonic copepods seems to be actively use their faecal pellets. Since benthic copepods (order Harpacticoida) live in the vicinity of their pellets, it remains unclear how important these pellets are for their feeding ecology. In the present study a laboratory experiment was conducted to analyse the importance of faecal pellets for the feeding ecology of the harpacticoid Paramphiascella fulvofasciata and its grazing pressure on two diatom species (Seminavis robusta, Navicula phyllepta). By quantifying the amount and volume of the produced faecel pellets in different treatments, it was tested to what extent the food source and the lack of faecal pellets would influence the production of faecal pellets. We found that the grazing pressure of P. fulvofasciata depended on the diatom density since only a top-down effect could be found on the smaller Navicula cells during its initial exponential growth phase. The grazer had a negative effect on the diatom growth and controlled the cell density to about 4,000 cells/cm2. In spite of the fact that the addition of faecal pellets did not show a significant positive effect on the assimilation of diatoms, the removal of faecal pellets strongly promoted the pellet production. Especially when grazing on Navicula the harpacticoid P. fulvofasciata produced significantly more and smaller faecal pellets when the pellets were removed. This outcome illustrates the need for faecal pellets of this harpacticoid copepod when grazing on the diatom Navicula. Apart from its selection for smaller diatom cells, it was suggested that the colonisation of heterotrophic bacteria enriched these pellets. This study is the first to indicate that trophic upgrading occurs on faecal pellets and not only on the initial autotrophic food sources per se.  相似文献   
940.
This paper is focused on novel utilizations of the fundamental modes of deformation of tube end forming for assembling sheet panels to thin-walled tubular profiles.The objective is to present an innovative and environmental friendly joining technology built upon the combination of compression beading with tube inversion that can successfully eliminate currently available technologies based on mechanical fixing with fasteners, welding and structural adhesive bonding. The technology works at room temperature, is capable of ensuring significant economic and time savings and offers potential for opening new markets for the assembly of lightweight frame structures.The presentation is supported by experimentation and numerical modelling based on independently determined mechanical properties of the materials with the purpose of characterizing and evaluating the process feasibility limits as a function of the major operative parameters.The feasibility of joining sheet panels to tubular profiles by means of the proposed technology is demonstrated by presenting industrial applications and by evaluating the performance of a safety auto part in an operation failure test.  相似文献   
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