scholarly journals Long-term monitoring of deficit irrigation regimes on citrus orchards in Sicily

2021 ◽  
Vol 52 (4) ◽  
Author(s):  
Daniela Vanella ◽  
Filippo Ferlito ◽  
Biagio Torrisi ◽  
Alessio Giuffrida ◽  
Salvatore Pappalardo ◽  
...  

The study aims to identify the responses of citrus orchards (C. sinensis (L.) Osbeck), grown under typical Mediterranean climatic conditions, to deficit irrigation (DI) regimes applied over more than a decade (2010-2020). In particular, the DI regimes were declined at the study site in terms of sustained deficit irrigation, regulated deficit irrigation, partial drying of the root-zone, with increasing severity of the water deficit, from 25% to 50% of the crop evapotranspiration, using surface and sub-surface micro-irrigation techniques. Long-term monitoring was set up for identifying the main processes acting at the soil-plant-atmosphere continuum (SPAC) level through direct in situ measurements of mass and energy fluxes (i.e., via micrometeorological technique) and the estimation of ETc and transpiration fluxes (i.e., via sap flow method), and the soil-plant-water processes (via geoelectrical techniques). In addition, the main physiological, qualitative, and quantitative parameters were evaluated since the beginning of the experiment. The results of the long-term experiment demonstrated the great adaptability of the crop species to sustain even the highest water reductions without substantial alterations of the main marketable productive and qualitative characteristics, evidencing the importance of controlling the SPAC dynamics for correctly applying the water restriction regimes.

2020 ◽  
Vol 172 ◽  
pp. 24005
Author(s):  
Nikola Pokorny ◽  
Tomas Matuska ◽  
Vladimir Jirka ◽  
Borivoj Sourek

Testing of two facade modules under outdoor climatic conditions of Central Europe has been performed for more than two years. The paper analyses the results of long-term monitoring and shows potential benefits of prismatic glazing and photovoltaic-thermal (PVT) collectors integrated into one component. The prismatic glazing reflects beam radiation during summer period and transmits it during the winter period. During summer month solar irradiation transmitted through the prismatic glazing can be about 44 % lower compared to conventional triple glazing. Glazed PVT collector generates heat and electricity simultaneously. PVT collector integrated in the façade module can achieve solar yield during summer 58 kWh/m2.month in heat and 6,3 kWh/m2.month in electricity.


Author(s):  
Dušan Katunský ◽  
Miloslav Bagoňa ◽  
Richard Baláž ◽  
Martin Lopušniak ◽  
Marián Verta’ ◽  
...  

Biologia ◽  
2008 ◽  
Vol 63 (6) ◽  
Author(s):  
Pavel Láska ◽  
Jan Rogl

AbstractThe periodicity of the fluctuations in the attacks of the carrot psyllid Trioza apicalis in long-term monitoring was studied by analysis of data of previous authors. The occurence of only one generation in the year shows that peaks of attack cannot arise suddenly in one year, but are prolonged over several years, as are the troughs of attack. This is the cause of the long-term fluctuation, which seems to be periodic. The statement of Ozols, that the period of the fluctuations of carrot psyllid was connected with climatic conditions via sunspot activity, was not evident statistically.


Author(s):  
Emilie Bednářová ◽  
Sabina Truparová ◽  
Lucie Merklová

The paper evaluates the onset and duration of spring vegetation phenological stages in a spruce monoculture of the third age class in relation to changing parameters of the environment in the region of the Drahanská vrchovina Upland. Temperature requirements of Norway spruce necessary for the onset particular phenological stages were evaluated on the basis of sums of effective temperatures > 5 oC. The period of 2005–2011 is processed in relation to long-term monitoring since 1991. Based on results obtained, there is considerable variability owing to changing climatic conditions in the onset of spring phenological stages in the course of monitored years. In recent years, the earlier onset of spring phenological stages occurs and their duration gets shorter. This phenomenon is caused by higher air temperatures in spring months. The statistical processing of results obtained demonstrated the high dependence of the onset of particular phenological stages on the temperature of air and soil. Particular factors affecting budbreak and foliation cannot be detached and thus, it is necessary to be evaluated as a complex of influences. Long-term phenological studies of forest trees can serve as the bioindicator of climatic changes.


2021 ◽  
pp. 125-131
Author(s):  
Frederic Stachurski ◽  
Nathalie Boulanger ◽  
Adrien Blisnick ◽  
Laurence Vial ◽  
Sarah Bonnet

Abstract The effect of climate on the evolution of tick populations remains difficult to disentangle from other possible causes and undoubtedly varies depending on the region concerned and local tick species. Large-scale, long-term monitoring is, therefore, necessary to accurately assess climatic impact on tick populations. Climate change can alter tick populations, either indirectly by affecting vertebrate host populations or directly by increasing or decreasing their numbers. These ectoparasites, and in particular hard ticks, spend almost their entire life cycle in the external environment, thus climatic conditions influence their activity, viability and distribution. This expert opinion aims to illustrate the impact of climate change, and its association with other variables, on the distribution and abundance of tick populations in Europe using Ixodes ricinus and Hyalomma marginatum as typical examples of endemic and invasive species, respectively.


2018 ◽  
Vol 11 (3) ◽  
pp. 901-915 ◽  
Author(s):  
V. Phogat ◽  
J. W. Cox ◽  
J. Šimůnek ◽  
P. Hayman

Abstract A numerical model (HYDRUS-1D) was used to evaluate the impacts of the long-term (2004–2015) use of sustained deficit irrigation (10% (D10%) and 20% (D20%) less than full), irrigations with increased water salinity (ECiw of 0.5 and 0.8 dS/m), 50% deficit irrigation during a drought period (DD50%), and DD50% coupled with an increased salinity of water (ECiw of 0.5 and 0.8 dS/m) on the water balance and salinity dynamics under grapevine in two soils at two locations with different climatic conditions. The results showed that D20% and DD50% significantly reduced water uptake and seasonal drainage (Dr) by the vines as compared to full irrigation. Vineyards established in light-textured soils showed two to five times larger drainage losses as compared to heavy-textured soils. The results revealed that the slight increase in the electrical conductivity of irrigation water (ECiw = 0.5 and 0.8 dS/m) increased the risks in terms of the amount of salts deposited in the soil and transport of large quantities of irrigation-induced salts beyond the root zone. Hence, it is imperative to monitor all of the important water, soil, and salinity drivers of agro-hydro-geological systems to understand the hydro-salinity dynamics and to ensure the long-term sustainability of irrigated viticulture.


2015 ◽  
Vol 37 (1) ◽  
pp. 51 ◽  
Author(s):  
Tomoyo Segawa ◽  
Catherine Kemper

Long-term monitoring of cetacean strandings is essential for good management. This study updates previous summaries for South Australia by adding up to 20 years of comprehensive data, including results of necropsy examinations. A total of 1078 records were examined. Thirty-one species were recorded: 9 (7% of records) mysticetes, 22 (88%) odontocetes and the rest (5%) unidentified. The number of species new to South Australia did not reach an asymptote, with potential for at least five additional species. Small cetaceans were more frequently recorded after 1990, possibly due to increased reporting effort. Stranding records increased markedly after 1970. Records for all species occurred year-round. Beaked whales stranded primarily during January–April, baleen whales during July–January and common dolphins during February–May. Geographic hotspots were identified and related to upwelling and reporting effort. A necropsy program since 1990 resulted in 315 of 856 records being assigned to a circumstance of death, with anthropogenic circumstances accounting for 42% of these. Known Entanglement (21%, 66 of 315) and Probable Entanglement (12%, 37 of 315) were the most recorded anthropogenic circumstances of death. Future research correlating strandings with oceanographic/climatic conditions may help to explain the documented patterns but first the effects of reporting effort need to be accounted for.


Author(s):  
Barbara S. Minsker ◽  
Charles Davis ◽  
David Dougherty ◽  
Gus Williams

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