Assessment of the allelopathic effect of leaf and seed extracts of Canavalia ensiformis as postemergent bioherbicides: A green alternative for sustainable agriculture

The herbicidal potential of aqueous extracts prepared from leaves and seeds of Canavalia ensiformis was tested by applying them postemergence to the crop weeds Ipomoea grandifolia and Commelina benghalensis. Considering the possible objective of using this bioherbicide on soybean fields, the extracts were also tested for deleterious effects on both transgenic and conventional soybean (Glycine max). In addition, the concentrations of four phenolic compounds and alkaloids with allelopathic properties in these extracts were estimated by high-performance liquid chromatography. The seed extract at concentrations of 25 g L^?1 and 50 g L^?1 was the most efficient postemergent bioherbicide. By applying these extracts, the development of the weed seed was progressively hindered until no recovery was observed. The application of 3.5 mL of crude extract on a plant that takes 30 days after germination of the seed to develop is sufficient for full control of the species within 5 days. Since both Ipomoea grandifolia and Commelina benghalensis are broadleaf dicotyledons, it is possible that other species with these characteristics can also be controlled or suffer the same effects under the action of the seed extract, if the same volume and mode of application are used. The selectivity of the treatments with 25 g L^?1 and 50 g L^?1 was assessed on transgenic and conventional cultivars. The treatments did not visibly affect the soybean cultivars, which developed normally during the observation period that continued up to 15 days after the death of the weeds.     

Performance of compostable baby used diapers in the composting process with the organic fraction of municipal solid waste

In modern societies, disposable diapers constitute a significant percentage of municipal solid wastes. They have been traditionally landfilled or incinerated as only limited recycling processes are being implemented in some parts of Europe. With the implementation of separated collection systems for the organic fraction of municipal solid wastes (OFMSWs) and the need to preserve the environment, compostable diapers have appeared in the market to avoid the main environmental impacts associated to non-biodegradable disposable diapers. In this study, a full-scale composting of door-to-door collected OFMSW with a 3% (w/w) of compostable diapers has also been carried out. Previously, lab-scale experiments confirmed that almost 50% of carbon of compostable diapers is emitted as CO₂ under aerobic controlled conditions. The results obtained at full-scale demonstrate that both the composting process and the final end product (compost) are not altered by the presence of compostable diapers in crucial aspects such as pathogenic content, stability and elemental composition (including nutrients and heavy metals). The main conclusion of this study is that the collection of the OFMSW with compostable diapers can be a new way to transform this waste into high-quality compost.     

Prey capture in <Emphasis Type="Italic">Clausocalanus furcatus</Emphasis> (Copepoda: Calanoida). The role of swimming behaviour

Prey capture is a fundamental process for the success of copepods in food-diluted environments. This process is influenced by several factors, including swimming and predatory habits. This work is aimed at characterising the kinematic and fractal properties of the swimming trajectories and reconstructing the predatory horizon of the small calanoid copepod Clausocalanus furcatus. Results indicate that the motion of C. furcatus resembles a random process, mainly evolving in one direction, whereas its predatory horizon is confined to a small region frontal to the anterior end of the copepod. These outcomes are discussed in terms of specific adaptation taking into account the natural conditions experienced by C. furcatus in its environment.     

Adapting a geographical information system-based water resource management to the needs of the Romanian water authorities

Background, aim, and scope

The need for global and integrated approaches to water resources management, both from the quantitative and the qualitative point of view, has long been recognized. Water quality management is a major issue for sustainable development and a mandatory task with respect to the implementation of the European Water Framework Directive as well as the Swiss legislation. However, data modelling to develop relational databases and subsequent geographic information system (GIS)-based water management instruments are a rather recent and not that widespread trend. The publication of overall guidelines for data modelling along with the EU Water Framework Directive is an important milestone in this area. Improving overall water quality requires better and more easily accessible data, but also the possibility to link data to simulation models. Models are to be used to derive indicators that will in turn support decision-making processes. For this whole chain to become effective at a river basin scale, all its components have to become part of the current daily practice of the local water administration. Any system, tool, or instrument that is not designed to meet, first of all, the fundamental needs of its primary end-users has almost no chance to be successful in the longer term.

Materials and methods

Although based on a pre-existing water resources management system developed in Switzerland, the methodological approach applied to develop a GIS-based water quality management system adapted to the Romanian context followed a set of well-defined steps: the first and very important step is the assessment of needs (on the basis of a careful analysis of the various activities and missions of the water administration and other relevant stakeholders in water management related issues). On that basis, a conceptual data model (CDM) can be developed, to be later on turned into a physical database. Finally, the specifically requested additional functionalities (i.e. functionalities not provided by classical commercial GIS software), also identified during the assessment of needs, are developed. This methodology was applied, on an experimental basin, in the Ialomita River basin.

Results

The results obtained from this action-research project consist of a set of tangible elements, among which (1) a conceptual data model adapted to the Romanian specificities regarding water resources management (needs, data availability, etc.), (2) a related spatial relational database (objects and attributes in tables, links, etc.), that can be used to store the data collected, among others, by the water administration, and later on exploited with geographical information systems, (3) a toolbar (in the ESRI environment) offering the requested data processing and visualizing functionalities. Lessons learned from this whole process can be considered as additional, although less tangible, results.

Discussion

The applied methodology is fairly classical and did not come up with revolutionary results. Actually, the interesting aspects of this work are, on the one hand, and obviously, the fact that it produced tools matching the needs of the local (if not national) water administration (i.e. with a good chance of being effectively used in the day-to-day practice), and, on the other hand, the adaptations and adjustments that were needed both at the staff level and in technical terms.

Conclusions

This research showed that a GIS-based water management system needs to be backed by some basic data management tools that form the necessary support upon which a GIS can be deployed. The main lesson gained is that technology transfer has to pay much attention to the differences in existing situations and backgrounds in general, and therefore must be able to show much flexibility. The fact that the original objectives could be adapted to meet the real needs of the local end-users is considered as a major aspect in achieving a successful adaptation and development of water resources management tools. Time needed to setup things in real life was probably the most underestimated aspect in this technology transfer process.

Recommendations and perspectives

The whole material produced (conceptual data model, database and GIS tools) was disseminated among all river basin authorities in Romania on the behalf of the national water administration (ANAR). The fact that further developments, for example, to address water quantity issues more precisely, as envisaged by ANAR, can be seen as an indication that this project succeeded in providing an appropriate input to improve water quality in Romania on the long term.

     

Planning waste cooking oil collection systems

This research has been motivated by a real-life problem of a waste cooking oil collection system characterized by the existence of multiple depots with an outsourced vehicle fleet, where the collection routes have to be plan. The routing problem addressed allows open routes between depots, i.e., all routes start at one depot but can end at the same or at a different one, depending on what minimizes the objective function considered. Such problem is referred as a Multi-Depot Vehicle Routing Problem with Mixed Closed and Open Inter-Depot Routes and is, in this paper, modeled through a mixed integer linear programming (MILP) formulation where capacity and duration constraints are taken into account. The model developed is applied to the real case study providing, as final results, the vehicle routes planning where a decrease of 13% on mileage and 11% on fleet hiring cost are achieved, when comparing with the current company solution.     

Climate-induced changes in fish landings of different fleet components of Portuguese fisheries

For each Portuguese fleet component, landings of biogeographic groups of fish species were compared for the period of 1993–2009. Wide-distribution species were the most abundant in landings, but have shown a decreasing trend. Temperate species had higher landings in trawl fisheries, whereas subtropical species were most abundant and exhibiting an increasing trend in landings of multi-gear fisheries. A latitudinal gradient was observed, with landings of temperate species being more important in the North-western coast than in the South-western and South coasts. Although trawl fisheries were relatively more important in the North-western coast, there has been a recent increase in the relative importance of multi-gear fisheries and of subtropical species in this area. The increasing relative importance of subtropical species in Portuguese fisheries along with the fact that landings of subtropical species were higher in multi-gear fisheries could indicate an easier adaptation of Portuguese multi-gear fisheries to the effects of climate change. However, as multi-gear fisheries include a wide range of gears, techniques and target-species, they may not all respond in the same manner to changes in fish species’ distribution. Among multi-gear fisheries, trammel nets catch a wider variety of species and a wider size range than gill nets or longlines; thus, trammel net fishers can adapt to changes in abundance of the main target species more readily than those using more species- and size-specific gears. Therefore, trammel net fisheries could more easily adapt to the effects of climate change on fish distribution than gill net or longline fisheries.     

Land use changes and its impacts on water resources in Nile Delta region using remote sensing techniques

Sustainable water resources management plans depend on reliable monitoring of land use –land cover (LULC) changes. The use of the remote sensing techniques in LULC changes detection brings consistency and reliability to the decision maker at regional scale. Three temporal data sets of images were used to obtain the land cover changes in this study: Landsat-5 Thematic Mapper (TM) acquired in 1984, and Landsat-7 enhanced Thematic Mapper acquired in 2000 and 2005 consequently. Each temporal data set consists of four Landsat scenes, which were mosaicked to cover the whole Nile Delta. Two different supervised classification algorithms were implemented to produce classification maps in thematic form. Support vector machine showed higher classification accuracies in comparison with maximum likelihood classification. The results indicated that the rapid imbalance changes occurred among three land cover classes (urban, desert, and agricultural land). These changes powered the land degradation and land fragmentation processes over the agricultural land exclusively due to urban encroachment. Slight land cover changes were detected between fish farms and surface water land cover classes.     

Subjective Annoyance Response to Diesel Engine Sound During Idling Conditions

Subjective annoyance response to diesel engine sound during idling conditions was evaluated by 80 participants. Eight different sound spectra were presented to the participants at a constant level of 80 dB(A) in a paired comparison procedure. Stereo-recorded sound stimuli were played back through a pair of loudspeakers in an anechoic room. Four objective parameters of loudness, sharpness, impulsiveness, and roughness were found to be the determining factors that cause subjective annoyance. An annoyance prediction model for the test stimuli of an idling diesel engine was developed on the basis of these factors. The objective parameters and their interactions have a significant effect on the annoyance prediction model. The spectral distribution indicated by test participants to be pleasant can be used as a basis for appropriate modification of engine sound. A single microphone measurement in free field conditions can be used to estimate objective parameters for defining the cause of annoyance.     

Electric Field Prediction for a Human Body-Electric Machine System

A system consisting of an electric machine and a human body is studied and the resulting electric field is predicted. A 3-phase induction machine operating at full load is modeled considering its geometry, windings, and materials. A human model is also constructed approximating its geometry and the electric properties of tissues. Using the finite element technique the electric field distribution in the human body is determinedfor a distance of 1 and 5 m from the machine and its effects are studied. Particularly, electric field potential variations are determined at specific points inside the human body and for these points the electric field intensity is computed and compared to the limit values for exposure according to international standards.     

Human Activities in Natura 2000 Sites: A Highly Diversified Conservation Network

The Natura 2000 network was established across the European Union’s (EU) Member States with the aim to conserve biodiversity, while ensuring the sustainability of human activities. However, to what kind and to what extent Natura 2000 sites are subject to human activities and how this varies across Member States remains unspecified. Here, we analyzed 111,269 human activity records from 14,727 protected sites in 20 Member States. The frequency of occurrence of activities differs among countries, with more than 86 % of all sites being subjected to agriculture or forestry. Activities like hunting, fishing, urbanization, transportation, and tourism are more frequently recorded in south European sites than in northern or eastern ones. The observed variations indicate that Natura 2000 networks are highly heterogeneous among EU Member States. Our analysis highlights the importance of agriculture in European landscapes and indicates possible targets for policy interventions at national, European, or “sub-European” level. The strong human presence in the Natura 2000 network throughout Member States, shows that conservation initiatives could succeed only by combining social and ecological sustainability and by ensuring the integration of policies affecting biodiversity.