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Cannibalism and its importance in Aquaculture: A review
No full textIntracohort cannibalism may lead to significant losses during the early life stages of farmed fish. The mechanisms driving cannibalism dynamics are common across many fish species and are closely linked to the factors that influence growth variation within a population. This genetically encoded behaviour allows the individual to eliminate competitors in the competition for resources and increases the chances of survival and reproduction. Many fish species display aggression towards individuals of the same species, which can often lead to cannibalistic behavior. This foraging strategy is also present in intensive aquaculture systems, and its economical, ecological and phylogenetic implications have been debated by many researchers. Many fish species can be produced economically in recirculation aquaculture (RAS) systems, but the efficiency of larval and juvenile rearing remains a bottleneck for most species. The success of initial rearing depends on many factors. In addition to genetic factors, the level of cannibalism is mainly influenced by the applied production and feeding technology. Literature suggests that mortality during larval rearing can be as high as 50%, largely due to aggression. In the case of predatory fish species, the presence or absence of certain husbandry conditions can lead to even higher levels of cannibalism, which significantly reduces production yields by causing mortality and secondary injuries, thus further decreasing the survival rate. This review therefore aims to identify and quantify the effects of biotic and abiotic factors that influence cannibalism
Physiological characteristics of a promising black locust (Robinia pseudoacacia L.) clone under marginal site conditions
No full textThis paper studies the physiological characteristics of a promising black locust (Robinia pseudoacacia L.) clone, Farkasszigeti, compared to common black locust (control), under marginal site conditions in Eastern Hungary. A clone trial was established in 2022 near Debrecen to test new black locust clones, with measurements of photosynthesis (net assimilation, efficiency of photosystem II, intercellular CO2 level) and water-use characteristics (transpiration, stomatal conductance, water use efficiency etc.), using LI-6800 (LI-COR) portable photosynthesis system. However, the measured values were very low, indicating drought and heat stress. The results revealed that Farkasszigeti exhibited better net assimilation (2.13±0.75 µmol CO2 m-2 s-1), transpiration (1.41±0.20 mmol H2O m-2 s-1) and stomatal conductance (0.017±0.002 mol m-2 s-1) than the control, with significant differences (p=0.05). Furthermore, its photosystem II was more efficient, thus it has better heat tolerance. Although the clone Farkasszigeti was proved to be better in terms of water use efficiency values, no significant difference was observed in comparison with the control common black locust. Today, under changing climatic conditions, the study of physiological adaptation of tree species and clones has a crucial role
AZ „ÖSSZEILLESZKEDÉS” VÁLTOZATAI – AZ AKKULTURÁCIÓTÓL AZ ASSZIMILÁCIÓIG. (A DUNAMELLÉKI ÉS DUNÁNTÚLI ZSIDÓ SZÁRMAZÁSÚ REFORMÁTUS EGYETEMI TANÁROK ÉLETRAJZI ADATTÁRA ÉS ÉLETÚTLEÍRÁSA) : (MAGYARORSZÁGI EGYETEMI TANÁROK ÉLETRAJZI ADATTÁRA 1848-1944. IV.)
Full text linkA Kovács I. Gábor vezetésével működő csoport elitkutatási anyaggyűjtésének ötödik (és egyben az egyetemi tanárok életrajzi adattárainak negyedik) kötetét veheti kezébe a kedves olvasó. Mindegyikről korábban a Gerundium folyóiratban is megjelent recenzió.A Kovács I. Gábor vezetésével működő csoport elitkutatási anyaggyűjtésének ötödik (és egyben az egyetemi tanárok életrajzi adattárainak negyedik) kötetét veheti kezébe a kedves olvasó. Mindegyikről korábban a Gerundium folyóiratban is megjelent recenzió.
ELTE EÖTVÖS KIADÓ, Eötvös Lóránd Tudományegyetem, Budapest, 2022
A global bibliographic review of soil variability trends on arable land: An impetus to sustainable land management
Full text linkCrop production is significantly affected by soil properties under the influence of climate, management practices, and geographical location. Soil variability affects the development, quality, biochemical reactions, and heterogeneity of soil. The most recent research has focused on soil variability monitoring, highlighting the importance of soil testing. This review aimed at identifying global research trends and assessing soil testing in monitoring variability on arable land, based on the bibliographic method. Literature search in Scopus Database (2020-2023) yielded 8,898 documents, refined to 815 articles. VOSviewer 1.6.20 Software was used for analysing exported data. The results revealed a growing emphasis on monitoring soil variability, with key countries including India, United States of America (USA), China, Australia, Canada, United Kingdom, and Brazil. Funding mainly came from Asia, North America, and Europe. Common monitoring approaches included soil tests and remote sensing, focusing on organic carbon, nitrogen, phosphorus, potassium, microorganisms, and soil moisture. However, digital illiteracy and high costs were major hindrances to using remote sensing and modern soil testing tools. The study suggests that whereas soil variability monitoring is essential for sustainable land management, development of affordable soil testing equipment and improved digital education are needed for its enhanced adoption
Evaluation of Lipizzaner mares’ fertility data in 10 Hungarian stud farms
Full text linkDespite numerous studies on the genetic background and performance traits of the Lipizzan breed, fertility characteristics of Hungarian Lipizzan mares have not been systematically examined. This study evaluates the reproductive performance of 220 Lipizzaner mares from 10 Hungarian stud farms, born during the period of 1981 to 2019, using breeding records from 1998 to 2022. The mares were grouped into 25 mare families and 24 birth cohorts. Data on successful pregnancies and foalings were analyzed with respect to age, family affiliation, and breeding year. Results show that mares aged 8–12 years had the highest fertility rates, while a gradual decline was observed after 15 years. Breeding activity increased markedly after 2011, peaking in 2022 with the highest number of matings and foals born. Fertility varied considerably among mare families: some achieved consistently high reproductive success, while others showed low or zero foaling rates despite repeated matings. Hungarian mare families generally produced better fertility results, whereas Fogaras families displayed greater heterogeneity. The study emphasizes the importance of monitoring reproductive efficiency in small mare families, as unfavorable fertility trends may jeopardize their long-term viability. These findings contribute to improving breeding strategies and ensuring the preservation of genetic diversity in the Hungarian Lipizzaner population
A kollektív szerződések szerepe a munkaidő szabályozásában
Full text linkThe paper examines the role of collective agreements in regulating working time within the EU and Hungarian legal framework. It points out that although EU law provides collective agreements with considerable leeway to specify rules on working time and, in certain cases, to deviate from the working time directive, Hungarian labour law differs significantly from this approach. According to domestic research, collective agreements have low coverage, and in many cases the content of existing agreements is merely a literal repetition of the statutory rules. The study also analyses the collective agreement for the electricity industry which has extended scope for the whole sector. Overall, the author concludes that the Hungarian legal environment does not sufficiently encourage collective bargaining in the area of working time regulation and recommends a review of the regulatory framework.A tanulmány a kollektív szerződések munkaidő-szabályozásban betöltött szerepét vizsgálja az uniós és a magyar jogi keretek között. Rámutat arra, hogy bár az uniós jog a kollektív megállapodásoknak jelentős mozgásteret biztosít a munkaidőre vonatkozó szabályok pontosítására és adott esetben az azoktól való eltérésre is, a magyar munkajog gyakorlata ettől jelentősen eltér. A hazai kutatások szerint a kollektív szerződések lefedettsége alacsony, és a meglévő megállapodások tartalma sok esetben csupán a törvényi szabályok szó szerinti ismétlése. A tanulmány külön elemzi a villamosenergia-ipari ágazati kollektív szerződést. Összességében a szerző arra a következtetésre jut, hogy a magyar jogi környezet nem ösztönzi kellőképpen a kollektív alkut a munkaidő-szabályozás terén, és javasolja a szabályozási keretek felülvizsgálatát
CONTRIBUTION OF COMMUNITY BASED ORGANIZATIONS IN ENHANCING RURAL COMMUNITY DEVELOPMENT: INSIGHTS FROM OSUN STATE, NIGERIA
Full text linkThis study examined the contribution of community-based organizations (CBOs) to rural community development in Osun State, Nigeria. Specifically, it described the characteristics of CBOs, identified their goals, types, and development projects, determined their contributions to rural development, and identified challenges limiting their performance. A multi-stage sampling procedure was employed to select 48 registered CBOs across the state, with 180 respondents. Data were collected through structured interview schedules and analyzed using descriptive statistics, while Pearson Product Moment Correlation (PPMC) was applied to test the study hypotheses. Results indicated that the mean years of formation of CBOs was 21.3 ± 9.5 years, majority had written constitution with a mean membership strength of 40±12 members. Primary goal of CBOs was economic empowerment of members (85.4%), The most prevalent CBOs included landlord associations and social groups. Most CBOs initiated erection of security gate at community entrance (75%) and provision of vigilante (70/8%). Provision of security for community and government property (mean = 2.83) and implementing of developmental projects (mean = 2.70) were s the most prominent contribution of CBOs. The major constraints affecting CBO performance were lack of funds (mean = 1.85) and lack of government support (mean = 1.51). Statistically significant relationships were observed between contribution and leadership tenure (r = -0.276, p ≤ 0.01), operational constitution (r = -0.406, p ≤ 0.01), and membership size (r = 0.299, p ≤ 0.05). The study concluded that despite the fact that CBOs contributed meaningfully to rural development, their potential remains constrained by limited institutional and community support. It is recommended that government should recognize and institutionalize the role of CBOs in rural developmen
Érdekességek és változások a mecseki völgyek mohaflórájában
Full text linkThe paper discusses the bryophyte flora of 77 sites in the Mecsek Mountains, mainly in deeper valleys. It includes species that are new to the area’s flora and/or endangered in Hungary, as well as mosses that have become more widespread or locally abundant compared to data from 1968 and 1983. The names of the locations, their geographical centers (centroids), and the grid unit IDs of the Hungarian Flora Mapping Programme (HFMP), where the sites are located, are listed and referenced according to their number in the list. Some of the species are national rarities, such as Scleropodium touretii, newly recorded in the Mecsek in 2023. Its second known occurrence in Hungary is reported in the Enumeration. We detail the occurrences of several species new to South Transdanubia, including Dicranum spurium, Diplophyllum albicans, Hypnum jutlandicum, Isothecium myosuroides, Kindbergia praelonga, Rhynchostegiella curviseta, Riccardia palmata, and Sciuro-hypnum plumosum. Additionally, species newly recorded from the Mecsek Mountains include Fontinalis antipyretica, Leptodon smithii, Plagiomnium ellipticum, Pseudocampylium radicale, and Tortula brevissima. For two taxa, we present data of importance not only for the Mecsek, but also for the North-Hungarian Mts: Riccardia palmata, new for the Tornai-karszt, and Dicranum spurium, for which we confirm a very old record in the Zemplén Mts. We also note the widespread, sometimes massive occurrence of some aquatic and subaquatic mosses, e.g. Rhynchostegiella teneriffae, Hygrohypnum luridum, which have been recorded only once in the mountains in the last 50 years. The taxonomically uncertain Hygroamblystegium fluviatile with similar habitat requirements can now be found widely throughout the mountains. New populations of Palustriella commutata, considered endangered and declining in the country, have been found in the Mecsek. The expansion of (sub-)aquatic species is particularly surprising in the light of recent hydroecological studies indicating that the streams in the Mecsek are drying up. The situation is similar regarding Rhynchostegium rotundifolium, previously thought to be a Tilio-Acerion (slope and ravine forest) species, which is legally protected in Hungary and only had one record from the Mecsek in the last century. This forest species is now found in peri-urban, sub-urban, slightly to moderately disturbed and secondary habitats throughout the mountains. Similar to its preference in Germany, outside of semi-natural habitats it occurs mainly on built structures in forest edges, ruins, abandoned mine sites, often in stands mixed with black locust and contaminated with litter. Microeurhynchium pumilum, which prefers sub-Mediterranean and sub-Atlantic climate, shady and humid habitats, has become one of the most widespread and abundant forest bryophytes in the Mecsek, in contrast to its few records 60 years ago. Half (50%) of the new mosses in the flora of the Mecsek can be connected to the cooler boreal biome, while 21% is associated with the milder Mediterranean-Atlantic biome. The average of MAT (mean annual daily mean air temperatures averaged over one year) and MAP (accumulated precipitation amount over one year) of the 14 new species according to BET (Bryophytes of Europe Traits) indicates areas with much lower temperatures (7.7°C) than in Hungary, but with precipitation conditions (749 mm) similar to those in the Mecsek. The vast majority of the new species are extremely rare in Hungary, and are inconsistent with current climate warming trends. In contrast to the mosses with striking increase in records, the detection of new species is likely due to chance, in addition to systematic research at finer spatial scales, rather than to local expansion of the species. However, in the case of expanding and abundant species, it is still an open question whether their dynamics compared to 40-60 year old references are apparent or real: the result of sampling bias in previous surveys or a consequence of climate change. In any case, the abundance of the above mentioned bryophytes in the Mecsek is not consistent with their current Hungarian Red List threat classification, and this cannot be attributed to changes in definitions since 2010. The detected distribution and abundance, as well as the increase in the number of new species in the country within a decade, highlights the need for an updated Red List of Hungarian bryophytes.A dolgozat a Mecsek völgyeinek mohaflórájával, a hegység flórájára új és/vagy Magyarországon veszélyeztetett fajokkal, valamint az 50 évvel ezelőtti státuszukhoz képest gyakorivá, tömegessé váló mohákkal foglalkozik. Ezek között az ország flórájára 2023 óta új Scleropodium touretii második előfordulásáról, a Dél-Dunántúlra új Dicranum spurium, vagy csak a Mecsekre új Pseudocampylium radicale felfedezéséről is beszámolunk. Felhívjuk a figyelmet néhány, az elmúlt 50 évben a hegységben csak egy-egy adattal rendelkező patakparti moha (pl. Rhynchostegiella teneriffae) tömeges elterjedésére. Ez az expanzió különösen annak fényében tűnik meglepőnek, hogy a hidrobiológiai kutatások szerint a mecseki patakok kiszáradóban vannak. Az új fajok döntő többsége Magyarországon kifejezetten ritka, a melegedő klímának ellentmondó faj. A tömegesen észlelt mohákkal szemben kimutatásuk a finom térléptékű, szisztematikus kutatás mellett a véletlennek, és nem a fajok lokális expanziójának köszönhető. A fajok mecseki gyakorisága és az új fajok megjelenése felveti a magyarországi vörös lista aktualizálásának szükségét
Adatok a Pannon Ökorégió őshonos növényfajainak ismeretéhez II. (6–22)
Full text linkIn the second part of this article series, which provides data contributing to the knowledge of native plant species of the Pannonian Ecoregion, we address rare species – mostly legally protected in Hungary – belonging to the families Cephaloziaceae, Athyriaceae, Dryopteridaceae, Cystopteridaceae, Thelypteridaceae, Brassicaceae, Rosaceae, Elatinaceae, Apiaceae, Orobanchaceae, Liliaceae, and Orchidaceae. We report the current occurrence of Nowellia curvifolia in the Sub-Pannonian region of Slovenia. We present an exceptionally species-rich habitat for ferns (Athyrium filix-femina, Dryopteris carthusiana, D. dilatata, D. filix-mas, Gymnocarpium dryopteris, Polystichum aculeatum) from the ‘Borsodi ártér’ microregion. We provide data on the stands of Thelypteris palustris observed along the main irrigation canals of ‘Tiszántúl’ region. We publish new occurrence records contributing to the Hungarian distribution of Aethionema saxatile, Crataegus nigra, Elatine hungarica, Sium sisarum, Orobanche hederae, Himantoglossum adriaticum, Epipactis placentina, E. exilis, E. pseudopurpurata, and E. microphylla, as well as to the appearance of Helosciadium repens in urbanized environment. Gagea spathacea and G. bohemica are newly recorded for the Zemplén Mts; Epipactis nordeniorum and Epipogium aphyllum are new for the flora of the Mátra Mts; and Himantoglossum calcaratum is newly recorded for Hungary. We also present spontaneous establishment of several orchid species in the courtyard of a secondary school in Veszprém. Additionally, we report on the pollinating insects observed on the flowers of Sternbergia colchiciflora. Two previously misreported records are also corrected.A Pannon Ökorégió őshonos növényfajainak ismeretéhez adatokat szolgáltató cikksorozat második részében a Cephaloziaceae, Athyriaceae, Dryopteridaceae, Cystopteridaceae, Thelypteridaceae, Brassicaceae, Rosaceae, Elatinaceae, Apiaceae, Orobanchaceae, Liliaceae és Orchidaceae családokba tartozó ritks, Magyarországon többségében védett fajokkal foglalkozunk. Beszámolunk a Nowellia curvifolia aktuális előfordulásáról Szlovénia Szubpannon régiójában. Bemutatunk egy páfrányfajokban (Athyrium filix-femina, Dryopteris carthusiana, D. dilatata, D. filix-mas, Gymnocarpium dryopteris, Polystichum aculeatum) kivételesen gazdag élőhelyet a Borsodi ártérről. Közöljük a Thelypteris palustris-nak a Nagykunsági-öntöző-főcsatorna és a Keleti-főcsatorna mentén megfigyelt állományait. Új előfordulási adatokat közlünk az Aethionema saxatile, a Crataegus nigra, az Elatine hungarica, a Sium sisarum, az Orobanche hederae, Himantoglossum adriaticum, Epipactis placentina, E. exilis, E. pseudopurpurata, E. microphylla hazai elterjedéséhez, valamint a Helosciadium repens megjelenéséhez urbanizált környezetben. A Gagea spathacea és G. bohemica új a Zempléni-hegységben, az Epipactis nordeniorum és Epipogium aphyllum új a Mátra flórájában, a Himantoglossum calcaratum új Magyarországon. Bemutatjuk néhány orchidea faj spontán megtelepedését egy veszprémi középiskola udvarán. Emellett beszámolunk a Sternbergia colchiciflora virágain megfigyelt megporzó rovarokról. Két, korábban tévesen közölt adat korrigálásának is helyet adunk.
A közleményt a Magyar Tudományos Akadémia alapításának bicentenáriuma alkalmából Hazslinszky Frigyes, Frivaldszky Imre, Láng Adolf Ferenc, Richter Aladár, Jurányi Lajos, Kanitz Ágoston, Fekete Lajos, Mágócsy-Dietz Sándor, Hollós László, Tuzson János, Gombocz Endre, Moesz Gusztáv, Lengyel Géza, Győrffy István, Jávorka Sándor, Andreánszky Gábor, Szabó Zoltán, Rapaics Raymund, Soó Rezső, Zólyomi Bálint, Máthé Imre, Ubrizsy Gábor, Jakucs Pál és Fekete Gábor botanikus-akadémikusok emlékének ajánljuk
Népek és törzsek a Kárpát-medencében Y-kromoszóma eredmények a vaskortól a honfoglalásig
Full text linkAz archeogenetikai Y-kromoszóma adatok alkalmasak annak feltérképezésére, hogy a történelmi és prehistorikus korokban objektíven mérhető kapcsolatot (vagy annak hiányát) tárjunk fel az egykori népességek között, illetve a ma élő népességekkel, amelyből az etnikai identitásukra és általuk beszélt nyelvekre is megalapozott feltételezésekkel élhetünk. A vaskori Dunántúl genetikai adatai megerősítik a kelta hódítást, míg az Alföld déli részén a mai Dél-Balkáni népességek szarmatákkal való keveredését feltételezhetjük. A hun és avar északkelet-ázsiai elitek három azonosított nemzetségéből kettő megtalálható a mai székelységben, azonban a zsuanzsuan elitcsoport kihalt. A középső és késő avar korszak a korábbi elemek egymás mellett élését mutatja egy számszerű trák jellegű genetikai dominancia mellett. A település- és temetőszervezet alapvetően patriarchális. Az eleve nagyon változatos, többféle genetikai eredetű honfoglaló csoportok erre a sokszínűségre telepedtek rá, így a magyar nyelv számszerű kisebbségből nemzetformálóvá válását lingua franca egységesítő hatással magyarázhatjuk, amit a politikai hatalom centralizációja és az államalapítás kívánt meg