Chemical and biological indicators of water quality in three agricultural watersheds of the Po valley, Italy

open9noAgriculture has both direct and indirect effects on quality of surface water and is one of the key activities causing water quality degradation. Its environmental impact can be evaluated by the determination of indicators of the quality of water bodies that collect drainage and runoff waters from agricultural watersheds. For this research, the water quality draining from three watersheds, totally or partially cultivated, all within the Po river valley (Italy), was determined, using chemical indicators (N-NO3 and N-NH4 concentration, N balance), trophic status (chlorophyll-a concentration) and benthic population indexes. Together, they should provide an overview of the water status, which is supposed to be strictly related to the land use and the management. Results show that the chemical parameters are well related to land use and farming management: intensive agricultural activity leads to high N-NO3 concentration in water and N surplus and vice versa. The chlorophyll-a concentration follows the same trend, being linked to nitrogen loads and land use. Not always there is accordance between chemical and biological indicators: no direct correspondence is evident between the N-NO3 concentration in waters and benthic community. Its presence and abundance seems to be mostly correlated with the geomorphology, hydrology, riparian strips, etc. of the habitat than to the land use. Only the integration of chemical and biological parameters allows a correct understanding of the state of health of water body and benthic communities.openPIERI L.; VENTURA F.; VENTURA M.; TAGLIAVINI M.; PONTI M.; PISTOCCHI R.; ALBERTAZZI S.; VIGNUDELLI M.; ROSSI PISA P.PIERI L.; VENTURA F.; VENTURA M.; TAGLIAVINI M.; PONTI M.; PISTOCCHI R.; ALBERTAZZI S.; VIGNUDELLI M.; ROSSI PISA P

Altimetry for the future: Building on 25 years of progress

In 2018 we celebrated 25 years of development of radar altimetry, and the progress achieved by this methodology in the fields of global and coastal oceanography, hydrology, geodesy and cryospheric sciences. Many symbolic major events have celebrated these developments, e.g., in Venice, Italy, the 15th (2006) and 20th (2012) years of progress and more recently, in 2018, in Ponta Delgada, Portugal, 25 Years of Progress in Radar Altimetry. On this latter occasion it was decided to collect contributions of scientists, engineers and managers involved in the worldwide altimetry community to depict the state of altimetry and propose recommendations for the altimetry of the future. This paper summarizes contributions and recommendations that were collected and provides guidance for future mission design, research activities, and sustainable operational radar altimetry data exploitation. Recommendations provided are fundamental for optimizing further scientific and operational advances of oceanographic observations by altimetry, including requirements for spatial and temporal resolution of altimetric measurements, their accuracy and continuity. There are also new challenges and new openings mentioned in the paper that are particularly crucial for observations at higher latitudes, for coastal oceanography, for cryospheric studies and for hydrology. The paper starts with a general introduction followed by a section on Earth System Science including Ocean Dynamics, Sea Level, the Coastal Ocean, Hydrology, the Cryosphere and Polar Oceans and the ‘‘Green” Ocean, extending the frontier from biogeochemistry to marine ecology. Applications are described in a subsequent section, which covers Operational Oceanography, Weather, Hurricane Wave and Wind Forecasting, Climate projection. Instruments’ development and satellite missions’ evolutions are described in a fourth section. A fifth section covers the key observations that altimeters provide and their potential complements, from other Earth observation measurements to in situ data. Section 6 identifies the data and methods and provides some accuracy and resolution requirements for the wet tropospheric correction, the orbit and other geodetic requirements, the Mean Sea Surface, Geoid and Mean Dynamic Topography, Calibration and Validation, data accuracy, data access and handling (including the DUACS system). Section 7 brings a transversal view on scales, integration, artificial intelligence, and capacity building (education and training). Section 8 reviews the programmatic issues followed by a conclusion

Altimetry for the future: building on 25 years of progress

In 2018 we celebrated 25 years of development of radar altimetry, and the progress achieved by this methodology in the fields of global and coastal oceanography, hydrology, geodesy and cryospheric sciences. Many symbolic major events have celebrated these developments, e.g., in Venice, Italy, the 15th (2006) and 20th (2012) years of progress and more recently, in 2018, in Ponta Delgada, Portugal, 25 Years of Progress in Radar Altimetry. On this latter occasion it was decided to collect contributions of scientists, engineers and managers involved in the worldwide altimetry community to depict the state of altimetry and propose recommendations for the altimetry of the future. This paper summarizes contributions and recommendations that were collected and provides guidance for future mission design, research activities, and sustainable operational radar altimetry data exploitation. Recommendations provided are fundamental for optimizing further scientific and operational advances of oceanographic observations by altimetry, including requirements for spatial and temporal resolution of altimetric measurements, their accuracy and continuity. There are also new challenges and new openings mentioned in the paper that are particularly crucial for observations at higher latitudes, for coastal oceanography, for cryospheric studies and for hydrology. The paper starts with a general introduction followed by a section on Earth System Science including Ocean Dynamics, Sea Level, the Coastal Ocean, Hydrology, the Cryosphere and Polar Oceans and the “Green” Ocean, extending the frontier from biogeochemistry to marine ecology. Applications are described in a subsequent section, which covers Operational Oceanography, Weather, Hurricane Wave and Wind Forecasting, Climate projection. Instruments’ development and satellite missions’ evolutions are described in a fourth section. A fifth section covers the key observations that altimeters provide and their potential complements, from other Earth observation measurements to in situ data. Section 6 identifies the data and methods and provides some accuracy and resolution requirements for the wet tropospheric correction, the orbit and other geodetic requirements, the Mean Sea Surface, Geoid and Mean Dynamic Topography, Calibration and Validation, data accuracy, data access and handling (including the DUACS system). Section 7 brings a transversal view on scales, integration, artificial intelligence, and capacity building (education and training). Section 8 reviews the programmatic issues followed by a conclusion

On the Discriminating Power of Passivation and Higher-Order Interaction

none3noThis paper studies the discriminating power offered by higher-order concurrent languages, and contrasts this power with those offered by higher-order sequential languages (à la lambda-calculus) and by first-order concurrent languages (à la CCS). The concurrent higher-order languages that we focus on are Higher-Order pi-calculus (HOpi), which supports higher-order communication, and an extension of HOpi with passivation, a simple higher-order construct that allows one to obtain location-dependent process behaviours. The comparison is carried out by providing embeddings of first-order processes into the various languages, and then examining the resulting contextual equivalences induced on such processes. As first-order processes we consider both ordinary Labeled Transition Systems (LTSs) and Reactive Probabilistic Labeled Transition Systems (RPLTSs). The hierarchy of discriminating powers so obtained for RPLTSs is finer than that for LTSs. For instance, in the LTS case, the additional discriminating power offered by passivation in concurrency is captured, in sequential languages, by the difference between the call-by-name and call-by-value evaluation strategies of an extended typed lambda-calculus.mixedBernardo, Marco; Sangiorgi, Davide; Vignudelli, ValeriaBernardo, Marco; Sangiorgi, Davide; Vignudelli, Valeri

Nitrogen balance in a hilly semi-agricultural watershed in Northern Italy

The research was carried out for 7 years, 1998-2005, in a semi-agricultural watershed, called Centonara, set within a natural regional park and situated in the hills surrounding Bologna, northern Italy. This area is characterized by one of the most interesting badlands complexes in Europe and represents one of the main points of naturalistic interest. The watershed is partially cultivated (about 30% of the total area) with arable crops, mostly cereals and alfalfa. To evaluate the impact of agricultural activity on the eco-sustainability of this area, the nitrogen (N) balance was computed. Although it is only an estimation of the potential environmental damage, the nitrogen balance is a useful indicator of the risk posed to the environment from excessive nitrogen and can be useful to understand the possible effects of a certain type of agricultural and environmental management and policy. The balance was calculated by computing the difference between all inputs and all outputs. The nitrogen balance of the watershed was found to be sustainable, with an annual nitrogen balance ranging between –2.3 and +4.4 kg ha–1. Despite the limited presence of arable lands, the agricultural management played the main role in determining the sustainability of the watershed, strongly influencing both the principal N sources and sinks. In fact, major N inputs derived from inorganic fertilization (8.1-15.5 kg ha–1yr–1) and biological fixation (8.3-14.3 kg ha–1yr–1). On the other hand, plant removal constituted the most important output (17.7-25.6 kg ha–1yr–1). N losses in the drainage water were limited (3.0-9.5 kg ha–1yr–1) and the Centonara stream water was found to be unpolluted, with a nitrate concentration always below the EU limit for drinking water. The similar magnitude of total N inputs and outputs indicated that the crop management, especially the crop rotation and the N fertilization, in the Centonara watershed has reached a good level of ecological sustainability. Finally, the computation of the N fertilizer-use efficiency index resulted to be useful to identify which crop and which type of management (organic or conventional) were more suitable for the pedo-climatic condition of the studied area

A degree day model for durum wheat (Triticum durum, Desf.) across the Italian peninsula

Phenological field observations were used to parameterize and test a Degree Day model for durum wheat (Triticum durum, Desf.) across the Italian peninsula. Data come from different experimental fields located in northern, central and southern Italy and encompass scalar sowing dates, allowing to parameterize a model representative for a wide range of sites and growing seasons. To assure the basic assumption of the Degree Day method, wheat subphases were identified to enable the best linear relationship (less data dispersion and higher coefficient of determination) between developmental rates and average air temperature. Under proven linear temperature responses, the model gave satisfactory simulations of wheat phenology over different locations and sowing period (R2 = 0.96; RMSE = 8,4 days; no bias, minimal complexity), even if the heat supply (growing degree days counted from 0\ub0C) was very different among sites

ENVIRONMENTAL RISK EVALUATION TO ASSURE THE QUALITY OF AGRICULTURAL PRODUCTS

The quality of agricultural products may be influenced by the environmental pollution. The prevention of pollution risk, or at least its knowledge, can be supported by the monitoring of the pollutions sources of potential environmental risk (e.g., incinerators, thermal power plans, highways, industrial plants, etc.) near the agricultural area of production. An instrument to assess this potential risk, related to the presence of pollution sources, may be a “Precaution Index”. This index was developed starting from the inventory and geo-referencing of all pollution sources in the study area, using a GIS software. To take into account the relevance of each source, a multi-criteria decision analysis (MCDM), that is ideal to support spatial decision making process, was used. Results are represented in a digital map of “Precaution Index” for the considered regions