Zenodo (CERN European Organization for Nuclear Research), Jan 27, 2021
Sviluppo di un modello per la derivazione della presenza di vegetazione attiva basata su NDVI SEN... more Sviluppo di un modello per la derivazione della presenza di vegetazione attiva basata su NDVI SENTINEL. 7 Fornitura dei dati raster relativi alla percentuale di presenza di aree urbane su grigliato regolare di 10m ...... 11 Attività svolta e documento realizzato a cura di:
Assessment of the risk of malaria re-introduction in the Maremma plain (Central Italy) using a mu... more Assessment of the risk of malaria re-introduction in the Maremma plain (Central Italy) using a multi-factorial approach
Abstract Recent investigations have supported the possibility of predicting soil water content (S... more Abstract Recent investigations have supported the possibility of predicting soil water content (SWC) through a simplified soil water balance (WB) model fed with remotely sensed actual evapotranspiration (ETa) estimates. This approach, however, requires information on main soil features (i.e. depth, wilting point, field capacity) which are generally difficult to retrieve over large regions. The current paper proposes an alternative model which directly predicts SWC relying on the same logic of the recently proposed ETa estimation method, i.e. the combination of meteorological and normalized difference vegetation index (NDVI) datasets. The theoretical bases of the old and new SWC estimation methods are first described. Both methods are then applied in Central Italy using ancillary and Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI data having a spatial resolution of 250 m; the outputs obtained are assessed versus SWC measurements taken both continuously and instantaneously. In the former case three ecosystems are analyzed (i.e. the grassland of Amplero and the forests of Barbialla and Amiata), where SWC was measured by probes during three different years (2003, 2012 and 2018, respectively). The latter experiment concerns 362 sample sites where SWC gravimetric measurements were taken during a similar time span (2000–2018). In both cases SWC is first normalized into relative SWC (RSWC), which is more directly influential on vegetation conditions. The results of both experiments indicate that the two simulation methods perform similarly when the former is driven by adequate information on soil features. The main limitations of the two simulation approaches are due to the spatial resolution mismatch between SWC measurements and estimates, which has a relatively minor impact on the first three homogeneous areas but is decisive for the other sampled sites. In general, the new simulation method is capable of predicting RSWC with relatively high spatial and temporal resolution without the use of specific soil information.
International Journal of Applied Earth Observation and Geoinformation, 2020
The availability of accurate information on the water consumed for crop irrigation is of vital im... more The availability of accurate information on the water consumed for crop irrigation is of vital importance to support compatible and sustainable environmental policies in arid and semi-arid regions. This has promoted several studies about the use of remote sensing data to monitor irrigated croplands, which are mostly based on statistical classification and/or regression techniques. The current paper proposes a new semi-empirical approach that relies on a water balance logic and does not require local tuning. The method stems from recent investigations which demonstrated the possibility of combining standard meteorological data and Sentinel-2 (S-2) Multi Spectral Instrument (MSI) NDVI images to estimate the actual evapotranspiration (ETa) of irrigated Mediterranean croplands. This ETa estimation method is adapted to drive a simplified site water balance which, for each 10-m S-2 MSI pixel, predicts the irrigation water (IW), i.e. the water which is consumed in addition to that naturally supplied by rainfall. The new method, fed with ground and satellite data from two years (2018-2019), is tested in a Mediterranean area around the town of Grosseto (Central Italy), that is covered by a particularly complex mosaic of rainfed and irrigated crops. The results obtained are first assessed qualitatively for some fields grown with known winter, spring and summer crops. Next, the IW estimates are evaluated quantitatively versus ground measurements taken over two irrigated fields, the first grown with processing tomato in 2018 and the second with early corn in 2019. Finally, the IW estimates are statistically analyzed against various datasets informative on local agricultural practices in the two years. All these analyses indicate that the proposed method is capable of predicting both the intensity and timing of the IW supply in the study area. The method, in fact, correctly identifies rainfed and irrigated crops and, in the latter case, accurately predicts the IW actually supplied. The results of the quantitative tests performed on tomato and corn show that over 50 % and 70 % of the measured IW variance is explained on daily and weekly bases, respectively, with corresponding mean bias errors below 0.3 mm/day and 2.0 mm/week. Similar indications are produced by the qualitative tests; reasonable IW estimates are obtained for all winter, springs and summer crops grown in the study area during 2018 and 2019.
Assessment of the risk of malaria re-introduction in the Maremma plain (Central Italy) using a mu... more Assessment of the risk of malaria re-introduction in the Maremma plain (Central Italy) using a multi-factorial approach
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2019
Fabrication of Aluminum LM13/MoS2/TiO2 hybrid metal matrix composite via stir casting technique w... more Fabrication of Aluminum LM13/MoS2/TiO2 hybrid metal matrix composite via stir casting technique was carried out to analyze the wear characteristics at an elevated temperature of 150° C using pin on disc tribometer. The parameters namely load, sliding velocity and sliding distance were varied for five levels as per the run order generated from Response Surface Methodology. From experiments, it was observed that the wear rate decreased with reduced sliding velocity initially due to mechanically mixed layer formation and then increasess. Also the results showed a reduction in wear rate with low loading and sliding distance conditions. Minimum wear rate was observed at a load of (11N), sliding velocity (1m/s) and sliding distance (848m) which was the ideal condition. Results concluded that the load applied was the significant factor over rate of wear leading to the occurrence of deep grooves along with delamination at higher loads. At minimal loads, appearance of shallow grooves in the sliding direction was observed.Major Applications of AMMC include the manufacturing of piston liners in automobiles and bearings, gears for aircraft engines which are often subjected to high friction and temperatures.
ABSTRACT Drought is a recurrent feature of climate and can affect areas with different climate re... more ABSTRACT Drought is a recurrent feature of climate and can affect areas with different climate regimes and human activities. Its impacts depend on the duration, intensity and extent of precipitation deficiency and water demand for several purposes. Due to the complexity of this phenomenon, it is crucial to analyze both current conditions and evolution of a drought event in order to provide accurate, timely and affordable support for policy setting and impacts management. In this perspective the LaMMA Consortium and the IBIMET-CNR Institute are developing a comprehensive operational tool for quasi-real time drought monitoring and medium-long time forecasts in the Tuscany region (Central Italy), with the aim to deliver periodical, geo-referenced information about areas affected by an increasing reduction of available water resources. A coupled rainfall based and satellite derived monitoring system consists of a set of indices suitable for our region and selected taking into account data availability. This system allows the assessment of vegetation moisture and temperature conditions at different spatio-temporal scales. An analysis of vegetation performances related to temperature and moisture stress is made throughout Normalized Difference Vegetation Index (NDVI) anomalies and Vegetation Health Index (VHI), derived from the Terra-Moderate Resolution Imaging Spectroradiometer (MODIS) products, available since 2000 and updated each 16 days. These indices are selected in order to enhance the climate-based Standardized Precipitation Index (SPI) and Effective Drought Index (EDI), which provide multiple time scale drought occurrence and duration. Moreover, multi-temporal NDVI profiles of main Tuscan cultivations are used to monitor variations of seasonal growth in order to forecast possible crop yield reductions due to prolonged drought conditions. Data of SPI and EDI elaborated from long time series, starting from 1960, of a single rain gauge station or gridded over the whole region provide the base for seasonal outlooks of drought evolution. Forecasts of the next 1-3 months follow a physically-based statistical approach based on an “adaptive multi-regressive method” that takes into account potential predictors among a list of physical atmospheric indices and Sea Surface Temperature (SST) anomalies. Information about current condition related to the last 16 days available is delivered on the Consortium web site and uploaded on a WebGIS platform. Finally, monthly bulletins furnish a more detailed description of drought evolution throughout an analysis of the indices in the last 30 days and a forecast of the next 3 months. This comprehensive framework, composed by the monitoring and forecast systems, can become a timely and stand-alone multi-purpose tool for several final users, potentially able to give information useful for managing drought-related emergencies as crop yields losses, forest fires and water resources reduction.
The Maremma Plain (central Italy) was hyper-endemic for malaria until the mid-20th century, when ... more The Maremma Plain (central Italy) was hyper-endemic for malaria until the mid-20th century, when a national campaign for malaria elimination drastically reduced the presence of the main vector Anopheles labranchiae Falleroni. However, the introduction of rice cultivation over 30 yr ago has led to an increase in the An. labranchiae population and concern over possible malaria reemergence. We studied the impact of anthropogenic environmental changes on the abundance and distribution of An. labranchiae in Maremma, focusing on rice fields, the main breeding sites. Adults and larvae were collected in three main areas with diverse ecological characteristics. Data were collected on human activity, land use, and seasonal climatic and demographic variations. We also interviewed residents and tourists regarding their knowledge of malaria. Our findings showed that the most important environmental changes have occurred along the coast; An. labranchiae foci are present throughout the area, with massive reproduction strictly related to rice cultivation in coastal areas. Although the abundance of this species has drastically decreased over the past 30 yr, it remains high and, together with climatic conditions and the potential introduction of gametocyte carriers, it may represent a threat for the occurrence of autochthonous malaria cases. Our findings suggest the need for the continuous monitoring of An. labranchiae in the study area. In addition to entomological surveillance, more detailed knowledge of human-induced environmental changes is needed, so as to have a more complete database that can be used for vector-control plans and for properly managing emergencies related to autochthonous introduced cases.
Conventional meteorological data and remotely sensed Normalized Difference Vegetation Index (NDVI... more Conventional meteorological data and remotely sensed Normalized Difference Vegetation Index (NDVI) images can be proficiently combined to predict actual evapotranspiration (ET A) on different spatial and temporal scales. Up to now, however, the operational application of this approach in heterogeneous Mediterranean regions has found difficulty due to the insufficient spatial resolution of satellite sensors having high acquisition frequency (i.e. 250 m of Terra/Aqua Moderate Resolution Imaging Spectroradiometer, MODIS). The current study investigates the advantages brought for this objective by the recent availability of NDVI data taken from the Sentinel-2 MultiSpectral Instrument (MSI), which has a spatial resolution of 10 m. The investigation has been performed in two Mediterranean areas characterized by different spatio-temporal variability of vegetation cover. The first is a mountain coniferous forest, where such variability is low, while the second is a relatively small (around 10 ha) irrigated tomato field surrounded by other annual crops showing diversified growing cycles. An ET A estimation method based on NDVI data is applied in the two study areas and its performances are evaluated against ground references obtained through the elaboration of site measurements (i.e. meteorological, soil water content, and crop coefficient observations). The advantage of using MSI over MODIS NDVI images is marginal in the first case study, while is evident in the second. More particularly, such advantage is outstanding when the remote sensing method is applied in an operational mode, i.e. without using the information on the water supplied to the tomato crop by irrigation. This confirms that the utility of higher spatial resolution data is dependent not only on the fragmentation of the observed landscapes but also on the synchronicity of major vegetation growing cycles, which is influenced by both environmental and humaninduced factors.
055444083), (2) LaMMA Consortium, Sesto Fiorentino, Florence, Italy LaMMA Consortium and IBIMET-C... more 055444083), (2) LaMMA Consortium, Sesto Fiorentino, Florence, Italy LaMMA Consortium and IBIMET-CNR Institute are developing an operational system for drought monitoring and medium-long time forecasts in Tuscany region (Central Italy), in order to deliver periodical, timely, affordable, geo-referenced information about areas affected by an increasing reduction of available water resources. The coupled rainfall based and satellite derived monitoring system, consisting of a set of indices suitable for our region, allows the assessment of vegetation moisture and temperature conditions at different spatio-temporal scales. An analysis of vegetation performances related to temperature and moisture stress is made throughout Normalized Difference Vegetation Index (NDVI) anomalies and Vegetation Health Index (VHI), derived from the Terra-MODIS satellite products. These indices are selected in order to enhance the climate-based Standardized Precipitation Index (SPI) and Effective Drought Index (EDI), which provide multiple time scale drought occurrence and duration. Data of SPI elaborated from daily E-OBS gridded precipitation dataset from the ECA&D (European Climate Assessment & Dataset) project provide the base for seasonal outlooks of drought evolution. Forecasts of the next 1-3 months follow a physically-based statistical approach based on an "adaptive multi-regressive method" that takes into account potential predictors among a list of physical atmospheric indices and Sea Surface Temperature (SST) anomalies. Information about current condition and future evolution of a drought event is periodically delivered on the LaMMA web site and uploaded on an Open Source WebGIS platform. On-line monthly bulletins furnish a detailed description of drought evolution and an analysis of its impacts on forests and main tree crops in the last 30 days and a forecast of the next 3 months. This comprehensive framework can represent a quasi-real time and user-friendly web access multi-purpose operational service for final users, potentially able to give "easy to read" information useful for managing drought-related emergencies as crop yields losses, forest fires and water resources reduction.
3 Clima e impatti sul territorio Le condizioni meteo-climatiche sono un fattore determinante dell... more 3 Clima e impatti sul territorio Le condizioni meteo-climatiche sono un fattore determinante della struttura degli ecosistemi, influenzando il suolo, lo sviluppo della vegetazione, la disponibilità d'acqua, la biodiversità. La variabilità e le tendenze climatiche in atto in Toscana hanno avuto ed hanno un forte impatto su tutti i sistemi territoriali e sulle attività umane ad essi collegate, anche perchè vanno a sommarsi agli altri fattori di degrado e sfruttamento del territorio (urbanizzazione, inquinamento dei suoli, sovrasfruttamento agricolo, pastorale e delle attività produttive, ecc.). Uno dei principali effetti delle variazioni climatiche sul territorio è legato alle risorse idriche, sia in termini di quantità complessiva di acqua disponibile per le attività umane e per il mantenimento dell'equilibrio ambientale, che in termini di distribuzione temporale. La variabilità del regime pluviometrico e della sua distribuzione ha tra le sue conseguenze un impatto sulla disponibilità idrica nel corso della stagione. La sensibilità del ciclo idrologico alla variazione della temperatura e delle precipitazioni comporta modificazioni nell'umidità del suolo, nello scorrimento superficiale dell'acqua, nella portata dei fiumi e dei laghi. La temperatura influenza in vario modo ed è un fattore essenziale della vita del suolo. Le alternanze di periodi siccitosi a periodi più ricorrenti di eventi meteorici estremi, agendo sullo sviluppo della vegetazione e quindi sul grado di copertura vegetale del suolo, indebolisce la protezione operata dalla vegetazione rendendo devastanti gli effetti del ruscellamento superficiale e influenzando la possibilità di ricarico delle falde. Il circolo vizioso che si instaura tra cambiamento climatico, fenomeni di desertificazione e biodiversità fa sì che il territorio non sia più in grado di sostenere i sistemi produttivi e che in tali condizioni si verifichino fenomeni di "uso competitivo" delle risorse tra i diversi settori socio-economici.
Zenodo (CERN European Organization for Nuclear Research), Jan 27, 2021
Sviluppo di un modello per la derivazione della presenza di vegetazione attiva basata su NDVI SEN... more Sviluppo di un modello per la derivazione della presenza di vegetazione attiva basata su NDVI SENTINEL. 7 Fornitura dei dati raster relativi alla percentuale di presenza di aree urbane su grigliato regolare di 10m ...... 11 Attività svolta e documento realizzato a cura di:
Assessment of the risk of malaria re-introduction in the Maremma plain (Central Italy) using a mu... more Assessment of the risk of malaria re-introduction in the Maremma plain (Central Italy) using a multi-factorial approach
Abstract Recent investigations have supported the possibility of predicting soil water content (S... more Abstract Recent investigations have supported the possibility of predicting soil water content (SWC) through a simplified soil water balance (WB) model fed with remotely sensed actual evapotranspiration (ETa) estimates. This approach, however, requires information on main soil features (i.e. depth, wilting point, field capacity) which are generally difficult to retrieve over large regions. The current paper proposes an alternative model which directly predicts SWC relying on the same logic of the recently proposed ETa estimation method, i.e. the combination of meteorological and normalized difference vegetation index (NDVI) datasets. The theoretical bases of the old and new SWC estimation methods are first described. Both methods are then applied in Central Italy using ancillary and Moderate Resolution Imaging Spectroradiometer (MODIS) NDVI data having a spatial resolution of 250 m; the outputs obtained are assessed versus SWC measurements taken both continuously and instantaneously. In the former case three ecosystems are analyzed (i.e. the grassland of Amplero and the forests of Barbialla and Amiata), where SWC was measured by probes during three different years (2003, 2012 and 2018, respectively). The latter experiment concerns 362 sample sites where SWC gravimetric measurements were taken during a similar time span (2000–2018). In both cases SWC is first normalized into relative SWC (RSWC), which is more directly influential on vegetation conditions. The results of both experiments indicate that the two simulation methods perform similarly when the former is driven by adequate information on soil features. The main limitations of the two simulation approaches are due to the spatial resolution mismatch between SWC measurements and estimates, which has a relatively minor impact on the first three homogeneous areas but is decisive for the other sampled sites. In general, the new simulation method is capable of predicting RSWC with relatively high spatial and temporal resolution without the use of specific soil information.
International Journal of Applied Earth Observation and Geoinformation, 2020
The availability of accurate information on the water consumed for crop irrigation is of vital im... more The availability of accurate information on the water consumed for crop irrigation is of vital importance to support compatible and sustainable environmental policies in arid and semi-arid regions. This has promoted several studies about the use of remote sensing data to monitor irrigated croplands, which are mostly based on statistical classification and/or regression techniques. The current paper proposes a new semi-empirical approach that relies on a water balance logic and does not require local tuning. The method stems from recent investigations which demonstrated the possibility of combining standard meteorological data and Sentinel-2 (S-2) Multi Spectral Instrument (MSI) NDVI images to estimate the actual evapotranspiration (ETa) of irrigated Mediterranean croplands. This ETa estimation method is adapted to drive a simplified site water balance which, for each 10-m S-2 MSI pixel, predicts the irrigation water (IW), i.e. the water which is consumed in addition to that naturally supplied by rainfall. The new method, fed with ground and satellite data from two years (2018-2019), is tested in a Mediterranean area around the town of Grosseto (Central Italy), that is covered by a particularly complex mosaic of rainfed and irrigated crops. The results obtained are first assessed qualitatively for some fields grown with known winter, spring and summer crops. Next, the IW estimates are evaluated quantitatively versus ground measurements taken over two irrigated fields, the first grown with processing tomato in 2018 and the second with early corn in 2019. Finally, the IW estimates are statistically analyzed against various datasets informative on local agricultural practices in the two years. All these analyses indicate that the proposed method is capable of predicting both the intensity and timing of the IW supply in the study area. The method, in fact, correctly identifies rainfed and irrigated crops and, in the latter case, accurately predicts the IW actually supplied. The results of the quantitative tests performed on tomato and corn show that over 50 % and 70 % of the measured IW variance is explained on daily and weekly bases, respectively, with corresponding mean bias errors below 0.3 mm/day and 2.0 mm/week. Similar indications are produced by the qualitative tests; reasonable IW estimates are obtained for all winter, springs and summer crops grown in the study area during 2018 and 2019.
Assessment of the risk of malaria re-introduction in the Maremma plain (Central Italy) using a mu... more Assessment of the risk of malaria re-introduction in the Maremma plain (Central Italy) using a multi-factorial approach
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2019
Fabrication of Aluminum LM13/MoS2/TiO2 hybrid metal matrix composite via stir casting technique w... more Fabrication of Aluminum LM13/MoS2/TiO2 hybrid metal matrix composite via stir casting technique was carried out to analyze the wear characteristics at an elevated temperature of 150° C using pin on disc tribometer. The parameters namely load, sliding velocity and sliding distance were varied for five levels as per the run order generated from Response Surface Methodology. From experiments, it was observed that the wear rate decreased with reduced sliding velocity initially due to mechanically mixed layer formation and then increasess. Also the results showed a reduction in wear rate with low loading and sliding distance conditions. Minimum wear rate was observed at a load of (11N), sliding velocity (1m/s) and sliding distance (848m) which was the ideal condition. Results concluded that the load applied was the significant factor over rate of wear leading to the occurrence of deep grooves along with delamination at higher loads. At minimal loads, appearance of shallow grooves in the sliding direction was observed.Major Applications of AMMC include the manufacturing of piston liners in automobiles and bearings, gears for aircraft engines which are often subjected to high friction and temperatures.
ABSTRACT Drought is a recurrent feature of climate and can affect areas with different climate re... more ABSTRACT Drought is a recurrent feature of climate and can affect areas with different climate regimes and human activities. Its impacts depend on the duration, intensity and extent of precipitation deficiency and water demand for several purposes. Due to the complexity of this phenomenon, it is crucial to analyze both current conditions and evolution of a drought event in order to provide accurate, timely and affordable support for policy setting and impacts management. In this perspective the LaMMA Consortium and the IBIMET-CNR Institute are developing a comprehensive operational tool for quasi-real time drought monitoring and medium-long time forecasts in the Tuscany region (Central Italy), with the aim to deliver periodical, geo-referenced information about areas affected by an increasing reduction of available water resources. A coupled rainfall based and satellite derived monitoring system consists of a set of indices suitable for our region and selected taking into account data availability. This system allows the assessment of vegetation moisture and temperature conditions at different spatio-temporal scales. An analysis of vegetation performances related to temperature and moisture stress is made throughout Normalized Difference Vegetation Index (NDVI) anomalies and Vegetation Health Index (VHI), derived from the Terra-Moderate Resolution Imaging Spectroradiometer (MODIS) products, available since 2000 and updated each 16 days. These indices are selected in order to enhance the climate-based Standardized Precipitation Index (SPI) and Effective Drought Index (EDI), which provide multiple time scale drought occurrence and duration. Moreover, multi-temporal NDVI profiles of main Tuscan cultivations are used to monitor variations of seasonal growth in order to forecast possible crop yield reductions due to prolonged drought conditions. Data of SPI and EDI elaborated from long time series, starting from 1960, of a single rain gauge station or gridded over the whole region provide the base for seasonal outlooks of drought evolution. Forecasts of the next 1-3 months follow a physically-based statistical approach based on an “adaptive multi-regressive method” that takes into account potential predictors among a list of physical atmospheric indices and Sea Surface Temperature (SST) anomalies. Information about current condition related to the last 16 days available is delivered on the Consortium web site and uploaded on a WebGIS platform. Finally, monthly bulletins furnish a more detailed description of drought evolution throughout an analysis of the indices in the last 30 days and a forecast of the next 3 months. This comprehensive framework, composed by the monitoring and forecast systems, can become a timely and stand-alone multi-purpose tool for several final users, potentially able to give information useful for managing drought-related emergencies as crop yields losses, forest fires and water resources reduction.
The Maremma Plain (central Italy) was hyper-endemic for malaria until the mid-20th century, when ... more The Maremma Plain (central Italy) was hyper-endemic for malaria until the mid-20th century, when a national campaign for malaria elimination drastically reduced the presence of the main vector Anopheles labranchiae Falleroni. However, the introduction of rice cultivation over 30 yr ago has led to an increase in the An. labranchiae population and concern over possible malaria reemergence. We studied the impact of anthropogenic environmental changes on the abundance and distribution of An. labranchiae in Maremma, focusing on rice fields, the main breeding sites. Adults and larvae were collected in three main areas with diverse ecological characteristics. Data were collected on human activity, land use, and seasonal climatic and demographic variations. We also interviewed residents and tourists regarding their knowledge of malaria. Our findings showed that the most important environmental changes have occurred along the coast; An. labranchiae foci are present throughout the area, with massive reproduction strictly related to rice cultivation in coastal areas. Although the abundance of this species has drastically decreased over the past 30 yr, it remains high and, together with climatic conditions and the potential introduction of gametocyte carriers, it may represent a threat for the occurrence of autochthonous malaria cases. Our findings suggest the need for the continuous monitoring of An. labranchiae in the study area. In addition to entomological surveillance, more detailed knowledge of human-induced environmental changes is needed, so as to have a more complete database that can be used for vector-control plans and for properly managing emergencies related to autochthonous introduced cases.
Conventional meteorological data and remotely sensed Normalized Difference Vegetation Index (NDVI... more Conventional meteorological data and remotely sensed Normalized Difference Vegetation Index (NDVI) images can be proficiently combined to predict actual evapotranspiration (ET A) on different spatial and temporal scales. Up to now, however, the operational application of this approach in heterogeneous Mediterranean regions has found difficulty due to the insufficient spatial resolution of satellite sensors having high acquisition frequency (i.e. 250 m of Terra/Aqua Moderate Resolution Imaging Spectroradiometer, MODIS). The current study investigates the advantages brought for this objective by the recent availability of NDVI data taken from the Sentinel-2 MultiSpectral Instrument (MSI), which has a spatial resolution of 10 m. The investigation has been performed in two Mediterranean areas characterized by different spatio-temporal variability of vegetation cover. The first is a mountain coniferous forest, where such variability is low, while the second is a relatively small (around 10 ha) irrigated tomato field surrounded by other annual crops showing diversified growing cycles. An ET A estimation method based on NDVI data is applied in the two study areas and its performances are evaluated against ground references obtained through the elaboration of site measurements (i.e. meteorological, soil water content, and crop coefficient observations). The advantage of using MSI over MODIS NDVI images is marginal in the first case study, while is evident in the second. More particularly, such advantage is outstanding when the remote sensing method is applied in an operational mode, i.e. without using the information on the water supplied to the tomato crop by irrigation. This confirms that the utility of higher spatial resolution data is dependent not only on the fragmentation of the observed landscapes but also on the synchronicity of major vegetation growing cycles, which is influenced by both environmental and humaninduced factors.
055444083), (2) LaMMA Consortium, Sesto Fiorentino, Florence, Italy LaMMA Consortium and IBIMET-C... more 055444083), (2) LaMMA Consortium, Sesto Fiorentino, Florence, Italy LaMMA Consortium and IBIMET-CNR Institute are developing an operational system for drought monitoring and medium-long time forecasts in Tuscany region (Central Italy), in order to deliver periodical, timely, affordable, geo-referenced information about areas affected by an increasing reduction of available water resources. The coupled rainfall based and satellite derived monitoring system, consisting of a set of indices suitable for our region, allows the assessment of vegetation moisture and temperature conditions at different spatio-temporal scales. An analysis of vegetation performances related to temperature and moisture stress is made throughout Normalized Difference Vegetation Index (NDVI) anomalies and Vegetation Health Index (VHI), derived from the Terra-MODIS satellite products. These indices are selected in order to enhance the climate-based Standardized Precipitation Index (SPI) and Effective Drought Index (EDI), which provide multiple time scale drought occurrence and duration. Data of SPI elaborated from daily E-OBS gridded precipitation dataset from the ECA&D (European Climate Assessment & Dataset) project provide the base for seasonal outlooks of drought evolution. Forecasts of the next 1-3 months follow a physically-based statistical approach based on an "adaptive multi-regressive method" that takes into account potential predictors among a list of physical atmospheric indices and Sea Surface Temperature (SST) anomalies. Information about current condition and future evolution of a drought event is periodically delivered on the LaMMA web site and uploaded on an Open Source WebGIS platform. On-line monthly bulletins furnish a detailed description of drought evolution and an analysis of its impacts on forests and main tree crops in the last 30 days and a forecast of the next 3 months. This comprehensive framework can represent a quasi-real time and user-friendly web access multi-purpose operational service for final users, potentially able to give "easy to read" information useful for managing drought-related emergencies as crop yields losses, forest fires and water resources reduction.
3 Clima e impatti sul territorio Le condizioni meteo-climatiche sono un fattore determinante dell... more 3 Clima e impatti sul territorio Le condizioni meteo-climatiche sono un fattore determinante della struttura degli ecosistemi, influenzando il suolo, lo sviluppo della vegetazione, la disponibilità d'acqua, la biodiversità. La variabilità e le tendenze climatiche in atto in Toscana hanno avuto ed hanno un forte impatto su tutti i sistemi territoriali e sulle attività umane ad essi collegate, anche perchè vanno a sommarsi agli altri fattori di degrado e sfruttamento del territorio (urbanizzazione, inquinamento dei suoli, sovrasfruttamento agricolo, pastorale e delle attività produttive, ecc.). Uno dei principali effetti delle variazioni climatiche sul territorio è legato alle risorse idriche, sia in termini di quantità complessiva di acqua disponibile per le attività umane e per il mantenimento dell'equilibrio ambientale, che in termini di distribuzione temporale. La variabilità del regime pluviometrico e della sua distribuzione ha tra le sue conseguenze un impatto sulla disponibilità idrica nel corso della stagione. La sensibilità del ciclo idrologico alla variazione della temperatura e delle precipitazioni comporta modificazioni nell'umidità del suolo, nello scorrimento superficiale dell'acqua, nella portata dei fiumi e dei laghi. La temperatura influenza in vario modo ed è un fattore essenziale della vita del suolo. Le alternanze di periodi siccitosi a periodi più ricorrenti di eventi meteorici estremi, agendo sullo sviluppo della vegetazione e quindi sul grado di copertura vegetale del suolo, indebolisce la protezione operata dalla vegetazione rendendo devastanti gli effetti del ruscellamento superficiale e influenzando la possibilità di ricarico delle falde. Il circolo vizioso che si instaura tra cambiamento climatico, fenomeni di desertificazione e biodiversità fa sì che il territorio non sia più in grado di sostenere i sistemi produttivi e che in tali condizioni si verifichino fenomeni di "uso competitivo" delle risorse tra i diversi settori socio-economici.
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