Detrital zircon sources in the Ordovician metasedimentary rocks of the Moroccan Meseta: Inferences for northern Gondwanan passive-margin paleogeography

ABSTRACT Detrital zircon U-Pb geochronology has been widely used to constrain the pre-Carboniferous geography of the European and, to a lesser extent, the Moroccan Variscides. The latter have been generally considered as part of a long-lasting passive margin that characterized northern Gondwana from Ordovician to Devonian time, and was subsequently involved in the late Paleozoic Variscan orogeny. We report detrital zircon ages for three Early to Late Ordovician samples from the Beni Mellala inlier in the northeastern part of the Western Moroccan Meseta in order to discuss the temporal evolution of the sources of sediments in this region. The detrital zircon spectra of these samples, characterized by two main populations with mean ages of 630–610 Ma and 2170–2060 Ma, are typical of Cambrian–Devonian rocks from the Moroccan Variscides and confirm their link to the West African craton. A minor Stenian–Tonian population (peak at ca. 970 Ma) suggests the influence of a distant and intermittent NE African source (Sahara metacraton), which was probably interrupted after Ordovician time. Our data support previous interpretations of the Moroccan Meseta (and the entire northern Moroccan Variscides) as part of the northern Gondwana passive margin. The main sources of these sediments would have been the West African craton in the western regions of the passive margin (Moroc- can Meseta and central European Paleozoic massifs), and the Arabian-Nubian Shield and/or Sahara metacraton in the eastern areas (Libya, Egypt, Jordan, central and NW Iberian zones during Paleozoic time), where the 1.0 Ga detrital zircon population is persistent throughout the Ordovician–Devonian time span.

Incidence of COVID-19 in Children and Young People Who Play Federated Football

Aim: To determine the incidence of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infection in children and young people who play federated football. Methods: Prospective study, from October 2020 to January 2021, in players aged 4 to 19 years from federated football clubs in Galicia, Spain (N = 23,845). Outbreaks and cases of SARS-CoV-2 infection were recorded. The cumulative incidence was compared with the incidence registered in Galicia in the same age range. Results: The cumulative incidence was 29.8 cases per 10,000 licenses in 4 months, lower than the incidence registered in the general population for all ages and both sexes (283.7 per 10,000 inhabitants; rate ratio = 9.5). It was higher in January (40.7 per 10,000), coinciding with the population peak. More cases were registered in futsal (42.9 vs 27.5 per 10,000) and competitions with periodic screenings (127.4 vs 9.1 per 10,000). There were 2 outbreaks in 2389 teams (0.08%). Conclusion: The results support the safety of football practice in children and young people with prevention protocols.

Warm Mesoclimate Advances the Seasonal Dynamics of Harmonia axyridis in Urban Habitats

In 2016–2019, seasonal changes in the abundance of the harlequin ladybird Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) were established in the city center of Prague, Central Europe, and in its outskirts. Adults were sampled from lime trees (Tilia spp.) at regular intervals throughout the growing season. The abundance of H. axyridis paralleled the course of abundance of its prey, the aphid Eucallipterus tiliae L., which peaks either early or late in the season. As a result, the seasonal dynamics of H. axyridis were unimodal, with a peak in the early (late June—early July of 2017 and 2019) or late (late July—mid-September of 2016 and 2018) period of the season. In the early period, there was a small (1–4 days) difference in the timing of the peak of H. axyridis between the city center and the outskirts. In the late period, the peak occurred significantly earlier (by 13–21 days) in the city center due to the warmer climate there than in the outskirts. The difference in the timing of the population peak between both locations disappeared after recalculating the calendar to thermal time (number of day degrees above 10.6°C thresholds elapsed from the end of H. axyridis hibernation). The warm mesoclimate of the city center advances the seasonal dynamics of H. axyridis, contributing to the success of this invasive species in urban habitats.

Understanding Farmer and Government Measure in Rat Pests Control in Rice Fields

This paper discusses the control of rat pets through highlighting its population growth, ecosystem, types and possible mechanism to use. During extended periods of fallow, rice field rats tend to congregate in escape places (refuge regions) such as bushes, yards, or rice warehouses. Rice plants suffered damage equivalent to five times their feeding requirements when rats were present. Rats damage plants from the tiller stage to the maximal tiller stages by devouring the growth point and the soft base of the stem while leaving the other portions of the plant unharmed. Without intensive control efforts (since the start of MT1), the rat population density on MT2 is confirmed to be higher and poses a serious threat to the success of MT2 harvesting. In one rice growing season, there is one population peak so in the rice-paddy-fallow cropping pattern there are two (2) population peaks.

Habitat Structure and Abundance Dynamics of Marmota bobak Müller, 1776 (Sciuridae, Mammalia) in the Saratov Region at the End of the 20th – Start of the 21st Centuries

The paper presents data on the abundance of bobak marmot (Marmota bobak Müller, 1776), obtained from 1987 till 2019. All censuses were performed according to one technique developed by us in the late 1980s. During these long-term investigations, the structure of the bobak marmot areal in the Saratov region was studied. The dynamics of its numbers is described, and its trends for individual groups of districts were revealed, distinguished by trends, the time of the appearance of new settlements as a result of reintroduction after a prolonged depression in the numbers caused by both plowing of the steppes and the well-known events of the 1920s, 1930s and 1040s, when the bobak marmot provided the survival of some part of the population. It has been established that the population peak in the indigenous settlements that have been existing from the end of the Pleistocene – the beginning of the Holocene, was in 1980–1990. New settlements arise in the territories where the marmot was reintroduced, and the species abundance continues to grow. This, first of all, refers to the western slopes of the Volga Upland and the Oka-Don plain, formerly inhabited by marmots. An increase in the numbers of the Kazakhstan subspecies of the bobak is observed at the eastern end of the Syrt plain and on the spurs of the Common Syrt in the Saratov Trans-Volga region. The genetic studies of steppe marmots by R. V. Naumov (2019) on the right Volga bank of the Ulyanovsk region showed that a genetically homogeneous population lives on the vast territory of the Volga region. This casts doubt on the assumption of the existence of the Kozlovi subspecies of the bobak marmot in the local territories of the Voskresensk, Volsk and Khvalynsk districts of the Saratov region, which served as the ground for its inclusion into the new edition of the Red Data Book of the region, which we consider unreasonable (Resolution..., 2019).

Host preference, population dynamics, distribution, and injuries of Oligonychus punicae (Acari: Tetranychidae) in an eucalyptus clonal minigarden

Oligonychus punicae has potential for development in several species of eucalyptus. In this study was evaluated the preference for permanence and oviposition of O. punicae in different eucalyptus species. Additionally, we evaluated its dynamics and population distribution, as well as injuries in strains of Eucalyptus urophylla in a clonal minigarden. The preference for permanence and oviposition of O. punicae was evaluated using a test with and without choice in six species of Eucalyptus. We also analyzed the dynamics, population distribution and injury levels by O. punicae on E. urophylla in a clonal minigarden. We collected samples for 24 months and counted the number of eggs, immature and adult individuals. We calculated the Morisita dispersion index. We estimated injuries on leaves of E. urophylla using visual notes. In the test with choice, Eucalyptus urophylla was the preferred host of O. punicae for permanence and oviposition. In the test without choice, the oviposition of O. punicae in eucalyptus species did not differ statistically until 24 hours of evaluation. However, there was a significant difference after 48 hours, with greater oviposition on Eucalyptus brassiana, Eucalyptus tereticornis and Eucalyptus grandis. In the population survey, we collected 3,293 mites. The population peak of O. punicae occurred in March and April 2018 and April 2019. Oligonychus punicae presented an aggregate distribution and caused injuries of 20% on average in leaves. These results are important to guide management strategies in specific infestation foci and optimizing the use of phytosanitary products.

Host preference, population dynamics, distribution, and injuries of Oligonychus punicae (Acari: Tetranychidae) in an eucalyptus clonal minigarden

Oligonychus punicae has potential for development in several species of eucalyptus. In this study was evaluated the preference for permanence and oviposition of O. punicae in different eucalyptus species. Additionally, we evaluated its dynamics and population distribution, as well as injuries in strains of Eucalyptus urophylla in a clonal minigarden. The preference for permanence and oviposition of O. punicae was evaluated using a test with and without choice in six species of Eucalyptus. We also analyzed the dynamics, population distribution and injury levels by O. punicae on E. urophylla in a clonal minigarden. We collected samples for 24 months and counted the number of eggs, immature and adult individuals. We calculated the Morisita dispersion index. We estimated injuries on leaves of E. urophylla using visual notes. In the test with choice, Eucalyptus urophylla was the preferred host of O. punicae for permanence and oviposition. In the test without choice, the oviposition of O. punicae in eucalyptus species did not differ statistically until 24 hours of evaluation. However, there was a significant difference after 48 hours, with greater oviposition on Eucalyptus brassiana, Eucalyptus tereticornis and Eucalyptus grandis. In the population survey, we collected 3,293 mites. The population peak of O. punicae occurred in March and April 2018 and April 2019. Oligonychus punicae presented an aggregate distribution and caused injuries of 20% on average in leaves. These results are important to guide management strategies in specific infestation foci and optimizing the use of phytosanitary products.

FRUIT FLIES (DIPTERA: TEPHRITIDAE) IN MANGO ORCHARDS IN THE MINAS GERAIS SEMI-ARID REGION*

ABSTRACT We studied the diversity and level of infestation of fruit flies in mango orchards in a semi -arid region in the state of Minas Gerais, Brazil. Surveys were conducted in orchards in the irrigated perimeter of Jaíba municipality in northern Minas Gerais, from November 2016 to November 2017. Sampling was conducted by collecting mangoes and trapping flies in McPhail traps. Of the total adult flies obtained (9,033), 8,902 specimens were Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), making it the predominant species collected in the traps (91.3%). ‘Palmer’ mango fruits were only infested with C. capitata, and showed high infestation rates (15.14 puparia kg-1 of fruit). The population peak of C. capitata coincided with the occurrence of mature mango fruits in the orchards. C. capitata was the most frequent and constant species identified in the survey and can be considered a dominant species.