435 research outputs found
A Simple Method to Estimate Weed Control Threshold by Using RGB Images from Drones
The estimation of the infestation level in a field and the consequent determination of the
economic threshold is a basic requisite to rationalize post-emergence weeding. In this study, a simple
and inexpensive procedure to determine the economic threshold based on weed cover is proposed.
By using high-resolution RGB images captured by a low-cost drone, a free downloadable app for
image processing and common spreadsheet software to perform the model parametrization, two
different methods have been tested. The first method was based on the joint estimation of the two
parameters involved in weed cover calculation, whereas the second method required the availability
of further images for the separate estimation of the first parameter. The reliability of the two methods
has been evaluated through the comparison with observed data and the goodness of fit in parameter
calibration has been verified by calculating appropriate quality indices. The results showed an
acceptable estimation of the weed cover value for the second method with respect to observed data
(0.24 vs. 0.17 m2 and 0.17 vs. 0.14 m2, by processing images captured at 10 and 20 m, respectively),
whereas the estimations obtained with the first method were disappointing (0.35 vs. 0.17 m2 and 0.33
vs. 0.14 m2, by processing images captured at 10 and 20 m, respectively)
CLUSTERING THE HETEROGENITY OF EU URBAN PERFORMANCES
Cities represent today the intrinsic socio-economic complexity of local systems. Looking at the performances of urban systems enable us to explaining the main factors of territorial development. By moving from the theory of "progressive systems", and assigning to the cities some of this theory's properties, it is possible to outline a methodological perspective to capture the emerging phenomena describing the cities' performances. Keeping this view in mind, the aim of the paper is facing the intrinsic socio-economic complexity and heterogeneity of cities within the EU integration policies.. In order to better qualify this issue, we provide a multidimensional scaling approach, as a quantitative method useful to compare the several urban performances by letting a cluster evidence among the EU cities emerge.Urban trajectories, progressive system, multidimensional scaling.
Studio di ETC applicato a motore ad accensione spontanea
Il presente studio ha riguardato l’analisi dell’applicazione di un electric turbo-compound (ETC) ad un motore ad accensione spontanea (motore Diesel), per il recupero dell’energia residua dai gas di scarico del motore.
Il tirocinio, svolto presso il Dipartimento di Ingegneria dell’Energia, dei Sistemi, del Territorio e delle Costruzioni (DESTEC) dell’Università di Pisa, fa riferimento ad una attività di ricerca svolta in collaborazione con l’Università di Genova e che ha come obiettivo principale quello di verificare l’applicabilità di tecnologie ETC a motori a combustione interna, sia del tipo ad accensione comandata (motori a benzina) che del tipo ad accensione spontanea (motori Diesel)
A multi-adaptive framework for the crop choice in paludicultural cropping systems
The conventional cultivation of drained peatland causes peat oxidation, soil subsidence,
nutrient loss, increasing greenhouse gas emissions and biodiversity reduction. Paludiculture
has been identified as an alternative management strategy consisting in the cultivation of
biomass on wet and rewetted peatlands. This strategy can save these habitats and restore the
ecosystem services provided by the peatlands both on the local and global scale.
This paper illustrates the most important features to optimise the crop choice phase, which is
the crucial point for the success of paludiculture systems.
A multi-adaptive framework was proposed. It was based on four points that should be
checked to identify suitable crops for paludicultural cropping system: biological traits,
biomass production, attitude to cultivation and biomass quality. The main agronomic
implications were explored with the help of some results from a plurennial open-field
experimentation carried out in a paludicultural system set up in the Massaciuccoli Lake Basin
(Tuscany, Italy) and a complete example of the method application was provided. The tested
crops were Arundo donax L., Miscanthus Ă— giganteus Greef et Deuter, Phragmites australis
L., Populus Ă— canadensis Moench. and Salix alba L. The results showed a different level of
suitability ascribable to the different plant species proving that the proposed framework can
discriminate the behaviour of tested crops. Phragmites australis L.was the most suitable crop
whereas Populus Ă— canadensis Moench and Miscanthus Ă— giganteus Greef et Deuter (in the
case of biogas conversion) occupied the last positions in the ranking
Rewetting in Mediterranean reclaimed peaty soils and its potential for phyto-treatment use
A pilot experimental field combining rewetting of reclaimed peaty soils and water phyto-treatment was set up in the Massaciuccoli Lake basin (Tuscany, Italy) to reduce the water eutrophication and peat degradation caused by almost a century of drainage-based agricultural use.
In this paper, we investigated the restoration process occurring consequently to the conversion of a drained area in a natural wetland system (NWS) (the partial top soil removal, the realization of a perimeter levee to contain the waters, the rewetting with the drainage waters coming from the of surrounding cultivated areas) and the capability of the spontaneous vegetation to catch nutrients acting as a vegetation filter. To follow the restoration process over time (2012e2016), we used a mixed approach merging phytosociological surveys with ortophotos taken by an Unmanned Aerial Vehicle (UAV). During the last year of observation (2016), we performed destructive sampling on the most widespread plant communities
in the area (Phragmites australis and Myriophyllum aquaticum community) to quantify the biomass production and the uptake of nitrogen and phosphorus.
Stands of Phragmites australis (Cav.) Trin. ex Steud. yielded more than Myriophyllum aquaticum (Vell.) Verdc. (4.94 kg m-2 vs 1.08 kg m-2). M. aquaticum showed higher nutrient contents (2.04% of N and 0.35% of P), however P. australis was able to take up more nutrients within the NWS because of its larger cover
and productivity. In the perspective of maximizing the plant development and consequently the amount of nutrients extracted from treated waters, the authors suggest 4-5 year-long-harvesting turns, better occurring in spring-summer
“A case of ecological renaturation in a drained Mediterranean peatland: the case study of the Massaciuccoli Lake basin (Tuscany, It)”
The Massaciuccoli Lake floodplain is located in the Natural Park of San Rossore, Migliarino and Massaciuccoli in NW of Tuscany (Italy). Since the 1930s, a large part of the Massaciuccoli floodplain has been drained for agricultural purposes. To ensure a water table depth suitable for cultivation, a complex network of artificial drains and pumping stations has been used to drain the superficial aquifer and rainwater. Land use is characterised by conventional agriculture (covers 80% of the area) and periurban infrastructures, such as a wastewater treatment plant. In the peatland area, cropping systems are based on continuous production of maize (Zea mays L.), sunflower (Heliantus annuus L.), wheat (Triticum spp. L.). As a consequence of land use, several environmental concerns arose in the last 50 years. The most important concerns are those related to:
I. eutrophication of the lake due to nutrient enrichment (N, P) in the surface- and groundwater.
II. the subsidence rate (2-3 m in 70 years) due to compaction and increased mineralization of peat.
The project RestoMedPeatland (https://sites.google.com/site/restomedpeatland/) started in 2011, identified rewetting and setting-up a phyto-treatment system as the solution for improving water quality,slowing down soil organic matter (SOM) mineralization, and, therefore, a method to restore the ecological functions of this site. A 15 ha experimental area was used to compare the efficiency of three different systems (A: constructed wetland, B: paludiculture system and C: natural wetland in treating the eutrophic drainage water coming from a sub-watershed in the reclamation district.In the natural wetland (C), after top soil removal, excavation and rewetting with drainage water, the vegetation has evolved naturally. The surveys carried out during the four years after pilot experimental field, highlighted the development of a spontaneous hydro-hygrophilous vegetation. This was mainly composed of helophytic communities dominated by Phragmites australis (Cav.) Trin. and Typha latifolia L., in addition to monophytic populations of Myriophillum spp., occupying different areas of the system according to the depth of excavation, for about 50% of the whole surface. The flora, currently, consists more than 30 species, as hydro-hygrophilous Alisma plantago-aquatica L., Juncus effusus L., Apium nodiflorum (L.) Lag, Lemna minor L., characteristic of the nearby Massaciuccoli Lake. The data collected so far showed a high and progressive growth of the biomass of the natural area, a dynamic upward trend of floristic-vegetation biodiversity, and, from a technical standpoint, a large phyto-treatment capability
Renaturation dynamics after the rewetting of a Mediterranean agricultural peatland
A new research project combining peatland rewetting and water phyto-treatment was set up in the Massaciuccoli Lake basin (Tuscany, Italy) to restore the peat degradation status and the water eutrophication conditions caused by almost a century of drained-based agricultural use. In a large scale phyto-treatment system, three different strategies (constructed wetland system, paludicultural system, natural wetland system) were studied to evaluate their efficiency in abating the nutrients loads from the drainage waters and to stop the peatland degradation.
In this research, we investigated the renaturation process occurring within the natural wetland system as a result of the different disturbances carried out: the top soil removal in the perimeter area, the realization of a perimeter levee to contain the waters, the rewetting with the waters coming from the drainage of surrounding areas
Modelling Approach for NBSs Suitability Assessment in an Agricultural Area under Changing Climate Conditions: Case Studies in the Massaciuccoli Catchment (Central Italy)
Nature-Based Solutions (NBSs) are considered worldwide as a suitable approach for mitigating the impact of industrial agriculture on sediments and nutrient losses. However, their actual effectiveness is still questioned. In cases where site measurements of NBS performance are scarce, models can provide useful insights if accurately set. This study analyzed the effects of vegetated buffer strips (VBSs) and winter cover crops (WCCs) planted in some herbaceous cropping
systems within the Massaciuccoli reclamation area (Vecchiano, Central Italy). Analyses stem from modelling water and soil dynamics by applying SWAT+ at field scale on high resolution close-range photogrammetric digital terrain model (DTM), real crop rotations, and a detailed calendar of the main agronomic interventions. The NBS implementation was modelled in two experimental areas, showing contrasting soil properties. Comparing results from the modelling of different scenarios highlighted that NBS mitigative effect is influenced by soil properties and local topographic irregularities, which could induce concentrated flows. Long term climate changes can induce relevant different effects by varying the nature of soil
Precision Nitrogen Management In Camelina: Preliminary Results From A Case Study In Central Italy
Nowadays, the use of advanced technologies in agriculture is mandatory in order to increase cropping system sustainability and quality. To guarantee a higher yield, farmers need to ensure the best health of their crops with, at the same time, the least environmental impact. Particular attention is generally paid to nitrogen fertilization since nitrogen use efficiency in modern agriculture is very low. It means that a lot of synthetic chemicals are wasted rather than utilized by crops with consequent environmental issues. The use of spectral reflectance indices, such as the normalized difference vegetation index (NDVI) and chlorophyll index (Dualex), are reliable indicators to determine N status of crop plants. In this contest, very scarce knowledge is available about the response of camelina - a promising oilseed crop for food, feed, and the bio-based industry - to different N rates as well as on the use of remote/proximal sensing. So, this study aimed to evaluate the effect of N fertilization rate and timing on camelina seed yield and quality. At the same time, biochemical parameters and NDVI by using proximal sensing techniques were assessed with the aim to optimise camelina agronomic management
RRAML: Reinforced Retrieval Augmented Machine Learning
The emergence of large language models (LLMs) has revolutionized machine
learning and related fields, showcasing remarkable abilities in comprehending,
generating, and manipulating human language. However, their conventional usage
through API-based text prompt submissions imposes certain limitations in terms
of context constraints and external source availability. To address these
challenges, we propose a novel framework called Reinforced Retrieval Augmented
Machine Learning (RRAML). RRAML integrates the reasoning capabilities of LLMs
with supporting information retrieved by a purpose-built retriever from a vast
user-provided database. By leveraging recent advancements in reinforcement
learning, our method effectively addresses several critical challenges.
Firstly, it circumvents the need for accessing LLM gradients. Secondly, our
method alleviates the burden of retraining LLMs for specific tasks, as it is
often impractical or impossible due to restricted access to the model and the
computational intensity involved. Additionally we seamlessly link the
retriever's task with the reasoner, mitigating hallucinations and reducing
irrelevant, and potentially damaging retrieved documents. We believe that the
research agenda outlined in this paper has the potential to profoundly impact
the field of AI, democratizing access to and utilization of LLMs for a wide
range of entities
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