CONTROL OF POTENTIAL MUSSEL RECRUITMENT TAKING INTO ACCOUNT SOME ENVIRONMENTAL PARAMETERS IN SEVASTOPOL ESTUARINE ZONE

In 2020-2021, potential recruitment of the mussel Mytilus galloprovincialis was measured in Sevastopol estuarine waters with regard to temperature, salinity, and pH in three depth horizons 1–3, 7, and 11 m. Compared to the previous annual period in 2021, spring mussel recruitment at all depth horizons in-creased by an order of magnitude. This increase was preceded by a mild winter. Also in 2021, a decrease in salinity and an increase in the vertical variability of the thermohaline structure of water were observed. The obtained data may indirectly indicate the improvement of environmental conditions for mussel productivity increase in 2021. The necessity of improving the method of the control for mussel recruit-ment related to possible vertical migrations of its post-larvae is shown.

Verification of district level weather forecast

IMD started issuing quantitative district level weather forecast upto 5 days on operational basis from 1st June, 2008. The products comprise of quantitative forecasts for seven weather parameters, viz., rainfall, maximum and minimum temperatures, wind speed and direction, relative humidity and cloudiness. The rainfall forecast is generated based on multi model-ensemble techniques (MME). For other parameters, ECMWF forecasts (presently IMDGFS) are used. These forecast products are further value added, by the respective MCs/RMCs and forwarded to 130 Agrometeorological Field Units (AMFUs) for preparation of weather based District Agromet Advisory Service bulletin. This Meteorological Monograph describes the performance skill of the operational district level weather forecasts over different parts of India rainfall during monsoon and temperature during winter and summer from 2012-14. The Monograph also highlights limitations and future scope for further improvement of the MME models. The verification results show weather forecasts are reasonably accurate and value addition has improved the accuracy of model forecast. Though the MME model could predict the weather in hill regions in the North but in other regions having some hilly areas, the same could not come true in respect of temperature. North East region of the country shows very less accuracy due to its predominantly humid sub-tropical climate with hot, humid summers, severe monsoons and mild winter.

Mapping Flood Extent and Frequency from Sentinel-1 Imagery during the Extremely Warm Winter of 2020 in Boreal Floodplains and Forests

The current study presents a methodology for water mapping from Sentinel-1 (S1) data and a flood extent analysis of the three largest floodplains in Estonia. The automatic processing scheme of S1 data was set up for the mapping of open-water flooding (OWF) and flooding under vegetation (FUV). The extremely mild winter of 2019/2020 resulted in several large floods at floodplains that were detected from S1 imagery with a maximal OWF extent up to 5000 ha and maximal FUV extent up to 4500 ha. A significant correlation (r2 > 0.6) between the OWF extent and the closest gauge data was obtained for inland riverbank floodplains. The outcome enabled us to define the water level at which the water exceeds the shoreline and flooding starts. However, for a coastal river delta floodplain, a lower correlation (r2 < 0.34) with gauge data was obtained, and the excess of river coastline could not be related to a certain water level. At inland riverbank floodplains, the extent of FUV was three times larger compared to that of OWF. The correlation between the water level and FUV was <0.51, indicating that the river water level at these test sites can be used as a proxy for forest floods. Relating conventional gauge data to S1 time series data contributes to flood risk mitigation.

Pea Breeding Lines Adapted to Autumn Sowings in Broomrape Prone Mediterranean Environments

In Mediterranean environments, with mild winters and dry summers, peas are planted in autumn or early winter to profit from winter rain and to avoid terminal drought and high summer temperatures. The root parasitic weed broomrape (Orobanche crenata) appears as a major limiting factor under these conditions. To address such specific growing conditions and associated constraints, targeted breeding is needed. We present here recent achievements in the development of pea lines arising from a wide hybridization program incorporating resistance to broomrape and to powdery mildew (Erysiphe pisi) from landraces and wild relatives. Their adaption to autumn sowings under Mediterranean rain fed conditions, and their agronomic performance and resistance to prevailing diseases is compared with those of check cultivars in a multi-environment field test with nine trials performed over three seasons. HA-GGE biplots were a powerful tool for comparison among accessions in terms of performance and stability for each trait assessed. Like this, breeding lines NS22, NS34, NS8, NS39, NS35, NS21 and NS83 over-yielded all check cultivars. Grain yield was strongly affected by broomrape infection, with little influence of powdery mildew and ascochyta blight. All breeding lines studied showed high to moderate resistance to broomrape, whereas all check cultivars were severely infected. Broomrape infection was not correlated with days to flowering, whereas powdery mildew infection was favored by long cycles. Broomrape infection was enhanced by mild winter temperatures before flowering and spring rain, whereas high spring temperatures hampered broomrape development.

Snow conditions in northern Europe: the dynamics of interannual variability versus projected long-term change

Simulations by the EURO-CORDEX (European branch of the Coordinated Regional Climate Downscaling Experiment) regional climate models indicate a widespread future decrease in snow water equivalent (SWE) in northern Europe. This concurs with the negative interannual correlation between SWE and winter temperature in the southern parts of the domain but not with the positive correlation observed further north and over the Scandinavian mountains. To better understand these similarities and differences, interannual variations and projected future changes in SWE are attributed to anomalies or changes in three factors: total precipitation, the snowfall fraction of precipitation and the fraction of accumulated snowfall that remains on the ground (the snow-on-ground fraction). In areas with relatively mild winter climate, the latter two terms govern both the long-term change and interannual variability, resulting in less snow with higher temperatures. In colder areas, however, interannual SWE variability is dominated by variations in total precipitation. Since total precipitation is positively correlated with temperature, more snow tends to accumulate in milder winters. Still, even in these areas, SWE is projected to decrease in the future due to the reduced snowfall and snow-on-ground fractions in response to higher temperatures. Although winter total precipitation is projected to increase, its increase is smaller than would be expected from the interannual covariation of temperature and precipitation and is therefore insufficient to compensate the lower snowfall and snow-on-ground fractions. Furthermore, interannual SWE variability in northern Europe in the simulated warmer future climate is increasingly governed by variations in the snowfall and snow-on-ground fractions and less by variations in total precipitation.

The Virus Yellows Epidemic in Sugar Beet in the UK in 2020 and the Adverse Effect of the EU Ban on Neonicotinoids on Sugar Beet Production

Virus yellows, the disease that was regarded as the worst scourge of sugar beet production in northern Europe in the 20th century, made a dramatic and devastating comeback in 2020, infecting up to 100% of some fields in the Fens of Cambridgeshire, and culminating in 38.1% infection of the national crop, the highest incidence of this pernicious disease since the epidemics of 1974–1976. The causes of the latest epidemic were the consequences of a perfect storm – high overwintering survival of the principal vector, the peach potato aphid, Myzus persicae, following a very mild winter, that resulted in early migration of infective aphids from overwintering hosts into newly emerging beet crops in April. These events, coupled with removal by EU dictate of the most efficient method of controlling the disease, namely the neonicotinoid seed treatments that had kept it under control for the previous 26 years, and the depletion of alternative insecticide spray products, either due to other bans, or having been rendered ineffective by the development of resistance in the vectors, meant that growers were fighting a losing battle almost from the day they sowed their seed. This article examines in detail how the 2020 epidemic developed, and the impact it had on the profitability of the sugar beet industry in the UK, and other parts of Europe. We also argue for a return of neonicotinoid seed treatments in future years to provide more effective control of future pandemics, and thus maintain the presence of this important break crop in arable rotations.