scholarly journals Germination behavior of the extremely rare Hladnikia pastinacifolia Rchb. (Apiaceae) – a Pleistocene in situ survivor

2019 ◽  
Vol 78 (2) ◽  
pp. 107-115
Author(s):  
Nina Šajna ◽  
Mirjana Šipek ◽  
Jelka Šuštar-Vozlič ◽  
Mitja Kaligarič

Abstract The present-day diversity of European flora in temperate mountain ranges was mainly formed by the negative effects of Pleistocene glaciation, which caused extinctions, restricted survival in situ, and subsequent re-colonization. Only rarely can we find species that have retained the molecular information of in situ survival. One such example is the extremely rare H. pastinacifolia Rchb., a monotypic genus and a narrow endemic of a mountain plateau south-east of the Julian Alps (Slovenia). We investigated the germination behavior and dispersal indications, which are often closely related to rarity and persistence and thus valuable for species conservation. Additionally, results about H. pastinacifolia help us to understand better what kind of species survived glaciations in Europe in situ. Our results show that these seeds have an underdeveloped embryo and require an ecologically relevant moist chilling period of about 100 days. The temperature sequence of the colder period that H. pastinacifolia seeds received in nature was 20/15 °C (52 days), 10/5 °C (40 days), 5/0 °C (65 days), 10/0 °C (45 days), 15/5 °C (21 days). The germination rate was high, significantly increased by scarification, and therefore prevented long-term seed bank establishment. We found cryptic seed differences expressed by two types of dormancy, each related to the order of the umbel: simple and complex morphophysiological dormancy for the lateral and the main umbel, respectively. Seed dispersal was very much influenced by precipitation in autumn. The germination and dispersal characteristics could explain the rarity and at the same time the persistence of H. pastinacifolia.

2016 ◽  
Vol 5 (2) ◽  
pp. 118 ◽  
Author(s):  
Thanh-Son Dao ◽  
Thi-My-Chi Vo ◽  
Thanh-Luu Pham

<p class="emsd-body"><span lang="EN-GB">Cyanobacteria are an essential part of aquatic ecosystems. However, they can cause detrimental impacts on other organisms of higher tropic levels in water bodies because of their potent toxic metabolites (e.g. microcystin) and other bioactive compounds. In this study we tested the long-term and negative effects of two non-microcystin producing cyanobacteria <em>Cylindrospermopsis curvispora</em> and <em>Planktothrix</em> sp. from Vietnam on <em>Daphnia magna</em> under the laboratory conditions. The animal was fed with mixtures of green alga, <em>Scenedesmus</em> sp., and <em>C. curvispora</em> or <em>Planktothrix</em> sp. at different ratios (100 % <em>Scenedesmus, </em>10 % cyanobacteria + 90 % <em>Scenedesmus</em>, 50 % cyanobacteria + 50 % <em>Scenedesmus</em>, 100 % cyanobacteria) over a period of 21days. The results showed that the <em>D. magna</em> fed with from 10 to 100 % cyanobacteria reduced their survival with density dependence, delayed or postponed its maturation. Besides, the cyanobacteria also inhibited the reproduction of adult <em>D. magna</em> consequently strongly prevent the next population development of <em>D. magna</em>. The species <em>C. curvispora</em> had stronger effect on survival, but less impact on maturation and reproduction of <em>D. magna</em> than <em>Planktothrix</em> sp, negatively. To our knowledge, this is the first report on negative effects of <em>C. curvispora</em> and <em>Planktothrix</em> sp. from Vietnam on life history traits of <em>D. magna</em>. Additionally, our results revealed that even non-microcystin producing cyanobacteria at low density could also have negative impacts on zooplankton consequently ecological balance interference. In situ investigations on the effects of cyanobacteria on zooplankton are suggested for more understanding on the ecological interactions of the two trophic levels of aquatic ecosystem.</span></p>


Forests ◽  
2018 ◽  
Vol 9 (8) ◽  
pp. 457 ◽  
Author(s):  
Anouschka Hof ◽  
Therese Löfroth ◽  
Jörgen Rudolphi ◽  
Timothy Work ◽  
Joakim Hjältén

Wood bioenergy may decrease the reliance on fossil carbon and mitigate anticipated increases in temperature. However, increased use of wood bioenergy may have large impacts on forest biodiversity primarily through the loss of dead wood habitats. We evaluated both the large-scale and long-term effects of different bioenergy extraction scenarios on the availability of dead wood and the suitability of the resulting habitat for saproxylic species, using a spatially explicit forest landscape simulation framework applied in the Swedish boreal forest. We demonstrate that bioenergy extraction scenarios, differing in the level of removal of biomass, can have significant effects on dead wood volumes. Although all of the scenarios led to decreasing levels of dead wood, the scenario aimed at species conservation led to highest volumes of dead wood (about 10 m3 ha−1) and highest connectivity of dead wood patches (mean proximity index of 78), whilst the scenario aimed at reaching zero fossil fuel targets led to the lowest levels (about 8 m3 ha−1) and least connectivity (mean proximity index of 7). Our simulations stress that further exploitation of dead wood from sites where volumes are already below suggested habitat thresholds for saproxylic species will very likely have further negative effects on dead wood dependent species.


2014 ◽  
Vol 63 (1) ◽  
pp. 139-148 ◽  
Author(s):  
Éva Lehoczky ◽  
M. Kamuti ◽  
N. Mazsu ◽  
J. Tamás ◽  
D. Sáringer-Kenyeres ◽  
...  

Plant nutrition is one of the most important intensification factors of crop production. The utilization of nutrients, however, may be modified by a number of production factors, including weed presence. Thus, the knowledge of occurring weed species, their abundance, nutrient and water uptake is extremely important to establish an appropriate basis for the evaluation of their risks or negative effects on crops. That is why investigations were carried out in a long-term fertilization experiment on the influence of different nutrient supplies (Ø, PK, NK, NPK) on weed flora in maize field.The weed surveys recorded similar diversity on the experimental area: the species of A. artemisiifolia, S. halepense and D. stramonium were dominant, but C. album and C. hybridum were also common. These species and H. annuus were the most abundant weeds.Based on the totalized and average data of all treatments, density followed the same tendency in the experimental years. It was the highest in the PK treated and untreated plots, and significantly exceeded the values of NK fertilized areas. Presumably the better N availability promoted the development of nitrophilic weeds, while the mortality of other small species increased.Winter wheat and maize forecrops had no visible influence on the diversity and the intensity of weediness. On the contrary, there were consistent differences in the density of certain weed species in accordance to the applied nutrients. A. artemisiifolia was present in the largest number in the untreated control and PK fertilized plots. The density of S. halepense and H. annuus was also significantly higher in the control areas. The number of their individuals was smaller in those plots where N containing fertilizers were used. Contrary to them, the density of D. stramonium, C. album and C. hybridum was the highest in the NPK treatments.


Author(s):  
Omar Hashim Thanon

Since peaceful coexistence reflects in its various aspects the concept of harmony between the members of the same society with their different national, religious and sectarian affiliations, as well as their attitudes and ideas, what brings together these are the common bonds such as land, interests and common destiny. But this coexistence is exposing for crises and instability and the theft of rights and other that destroy the communities with their different religious, national, sectarian, ethnic aspects, especially if these led to a crisis of fighting or war, which produces only destruction and mass displacement, ttherefore, the process of bridging the gap between the different parts of society in the post-war phase through a set of requirements that serve as the basis for the promotion of peaceful coexistence within the same country to consolidate civil and community peace in order to create a general framework and a coherent basis to reconstruct the community again.      Hence the premise of the research by asking about the extent of the possibility and ability of the community of religious and ethnic diversity, which has been exposed to these crises, which aimed at this diversity, basically to be able to rise and re-integrate within the same country and thus achieve civil and community peace, and Mosul is an example for that, the negative effects of the war and the accomplices of many criminal acts have given rise to hatred and fear for all, leading to the loss of livelihoods, which in the long term may have devastating social and psychological consequences.        To clarify all of this, the title of the first topic was a review of the concept and origin of peaceful coexistence. While the second topic dealt with the requirements of peaceful coexistence and social integration in Mosul, the last topic has identified the most important challenges facing the processes of coexistence and integration in Mosul. All this in order to paint a better future for the conductor at all levels in the near term at the very least to achieve the values of this peaceful coexistence, especially in the post-war period.


2020 ◽  
Vol 2 (1) ◽  
Author(s):  
ERCAN ÇATAK ◽  
Ali ATALAY

By obtaining changes on gene sequences of living things with the applied biotechnological methods; The idea of "Genetically Modified Organisms (GMO)", which aims to bring the living creature in question the original gene combinations with the desired characteristics, came to life in the late twentieth century. Despite the high probability that hunger problems may increase with the increasing world population; It is thought that plant breeding with classical farming methods will be insufficient in solving these problems. With various GMO applications developed all over the world, it aims to produce solutions to these problems. With the presence of GMO, it was possible to increase the shelf life of qualitative and quantitative values of the existing foods. In addition, decreases in agricultural use of pesticides used in agricultural struggle and threatening human health with GMO production are noteworthy. However, some concerns about anomalies that may occur in living things fed GMO products remain on the agenda. Because, in the long term, there is no clear and precise information that GMO will not have negative effects on living things; There are many recorded incidents showing their negative effects.


Author(s):  
T. D. Lipenetskaia

Under certain conditions of strong or prolonged external exposure, signs of either allostatic load or allostatic load are formed. The question of the different physiological nature of these states is discussed.


Author(s):  
Mohd. Shuhaimi Ishak

 Abstract Generally speaking, media is extensively used as the means to disseminate news and information pertaining to business, social, political and religious concerns. A portion of the time and space of media has now become an important device to generate economic and social activities that include advertising, marketing, recreation and entertainment. The Government regards them as an essential form of relaying news and information to its citizens and at the same time utilizes them as a powerful public relations’ mechanism. The effects of media are many and diverse, which can either be short or long term depending on the news and information. The effects of media can be found on various fronts, ranging from the political, economic and social, to even religious spheres. Some of the negative effects arising from the media are cultural and social influences, crimes and violence, sexual obscenities and pornography as well as liberalistic and extreme ideologies. This paper sheds light on these issues and draws principles from Islam to overcome them. Islam as revealed to humanity contains the necessary guidelines to nurture and mould the personality of individuals and shape them into good servants. Key Words: Media, Negative Effects, Means, Islam and Principles. Abstrak Secara umum, media secara meluas digunakan sebagai sarana untuk menyebarkan berita dan maklumat yang berkaitan dengan perniagaan, kemasyarakatan, pertimbangan politik dan agama. Sebahagian dari ruang dan masa media kini telah menjadi peranti penting untuk menghasilkan kegiatan ekonomi dan sosial yang meliputi pengiklanan, pemasaran, rekreasi dan hiburan. Kerajaan menganggap sarana-sarana ini sebagai wadah penting untuk menyampaikan berita dan maklumat kepada warganya dan pada masa yang sama juga menggunakannya sebagai mekanisme perhubungan awam yang berpengaruh. Pengaruh media sangat banyak dan pelbagai, samada berbentuk jangka pendek atau panjang bergantung kepada berita dan maklumat yang brekenaan. Kesan dari media boleh didapati mempengaruhi pelbagai aspek, bermula dari bidang politik, ekonomi, sosial bahkan juga agama. Beberapa kesan negatif yang timbul dari media ialah pengaruhnya terhadap budaya dan sosial, jenayah dan keganasan, kelucahan seksual dan pornografi serta ideologi yang liberal dan ekstrim. Kertas ini menyoroti isu-isu ini dan cuba mengambil prinsip-prinsip dari ajaran Islam untuk mengatasinya. Tujuan Islam itu sendiri diturunkan kepada umat manusia ialah untuk menjadi pedoman yang diperlukan untuk membina dan membentuk keperibadian individu dan menjadikan manusia hamba yang taat kepada Tuhannya. Kata Kunci: Media, Kesan Negatif, Cara-cara, Islam dan Prinsip-prinsip.


2020 ◽  
Vol 26 ◽  
Author(s):  
Jun-Jie Tang ◽  
Shuang Feng ◽  
Xing-Dong Chen ◽  
Hua Huang ◽  
Min Mao ◽  
...  

: Neurological diseases bring great mental and physical torture to the patients, and have long-term and sustained negative effects on families and society. The attention to neurological diseases is increasing, and the improvement of the material level is accompanied by an increase in the demand for mental level. The p75 neurotrophin receptor (p75NTR) is a low-affinity neurotrophin receptor and involved in diverse and pleiotropic effects in the developmental and adult central nervous system (CNS). Since neurological diseases are usually accompanied by the regression of memory, the pathogenesis of p75NTR also activates and inhibits other signaling pathways, which has a serious impact on the learning and memory of patients. The results of studies shown that p75NTR is associated with LTP/LTD-induced synaptic enhancement and inhibition, suggest that p75NTR may be involved in the progression of synaptic plasticity. And its pro-apoptotic effect is associated with activation of proBDNF and inhibition of proNGF, and TrkA/p75NTR imbalance leads to pro-survival or pro-apoptotic phenomena. It can be inferred that p75NTR mediates apoptosis in the hippocampus and amygdale, which may affect learning and memory behavior. This article mainly discusses the relationship between p75NTR and learning memory and associated mechanisms, which may provide some new ideas for the treatment of neurological diseases.


Author(s):  
Roy Livermore

The Earth’s climate changes naturally on all timescales. At the short end of the spectrum—hours or days—it is affected by sudden events such as volcanic eruptions, which raise the atmospheric temperature directly, and also indirectly, by the addition of greenhouse gases such as water vapour and carbon dioxide. Over years, centuries, and millennia, climate is influenced by changes in ocean currents that, ultimately, are controlled by the geography of ocean basins. On scales of thousands to hundreds of thousands of years, the Earth’s orbit around the Sun is the crucial influence, producing glaciations and interglacials, such as the one in which we live. Longer still, tectonic forces operate over millions of years to produce mountain ranges like the Himalayas and continental rifts such as that in East Africa, which profoundly affect atmospheric circulation, creating deserts and monsoons. Over tens to hundreds of millions of years, plate movements gradually rearrange the continents, creating new oceans and destroying old ones, making and breaking land and sea connections, assembling and disassembling supercontinents, resulting in fundamental changes in heat transport by ocean currents. Finally, over the very long term—billions of years—climate reflects slow changes in solar luminosity as the planet heads towards a fiery Armageddon. All but two of these controls are direct or indirect consequences of plate tectonics.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Sungmin O. ◽  
Rene Orth

AbstractWhile soil moisture information is essential for a wide range of hydrologic and climate applications, spatially-continuous soil moisture data is only available from satellite observations or model simulations. Here we present a global, long-term dataset of soil moisture derived through machine learning trained with in-situ measurements, SoMo.ml. We train a Long Short-Term Memory (LSTM) model to extrapolate daily soil moisture dynamics in space and in time, based on in-situ data collected from more than 1,000 stations across the globe. SoMo.ml provides multi-layer soil moisture data (0–10 cm, 10–30 cm, and 30–50 cm) at 0.25° spatial and daily temporal resolution over the period 2000–2019. The performance of the resulting dataset is evaluated through cross validation and inter-comparison with existing soil moisture datasets. SoMo.ml performs especially well in terms of temporal dynamics, making it particularly useful for applications requiring time-varying soil moisture, such as anomaly detection and memory analyses. SoMo.ml complements the existing suite of modelled and satellite-based datasets given its distinct derivation, to support large-scale hydrological, meteorological, and ecological analyses.


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