An overview of the taxonomic groups of NPPs

2021 ◽  
pp. SP511-2020-65
Author(s):  
Lyudmila Shumilovskikh ◽  
Jennifer M. K. O’Keefe ◽  
Fabienne Marret

AbstractNon-pollen palynomorphs (NPPs) are ‘extra’ microfossils often found in palynology slides. These include remains of organisms within the size range of pollen grains (∼10-250 microns), resistant to laboratory treatments used for the preparation of palynological samples. NPPs are a large and taxonomically heterogeneous group of remains of organisms living in diverse environments. Taxonomically, they belong to a wide variety of groups such as cyanobacteria, algae, vascular plants, invertebrates, and fungi. The aim of this chapter is to provide a general overview of NPP groups observed in palynology slides. It includes more than 40 of the most common groups starting with acritarcha, cyanobacteria and algae, moving through transitional groups to animals and fungi and finishing with human-made objects such as textile fibres. Although far from complete, it provides an updated overview of taxonomical diversity of NPPs and their indicator values. Further works on NPP identifications are of great importance to improve of our current knowledge. Since NPPs occur in all kinds of sediments, their analysis is a powerful tool for reconstructing environmental changes over time. Further detailed studies of specific NPP groups and their indicator values will open the way for new fields of study.

2020 ◽  
Vol 19 (2) ◽  
pp. 176-192
Author(s):  
Samantha Bedell ◽  
Janine Hutson ◽  
Barbra de Vrijer ◽  
Genevieve Eastabrook

: Obesity and gestational diabetes mellitus (GDM) are becoming more common among pregnant women worldwide and are individually associated with a number of placenta-mediated obstetric complications, including preeclampsia, macrosomia, intrauterine growth restriction and stillbirth. The placenta serves several functions throughout pregnancy and is the main exchange site for the transfer of nutrients and gas from mother to fetus. In pregnancies complicated by maternal obesity or GDM, the placenta is exposed to environmental changes, such as increased inflammation and oxidative stress, dyslipidemia, and altered hormone levels. These changes can affect placental development and function and lead to abnormal fetal growth and development as well as metabolic and cardiovascular abnormalities in the offspring. This review aims to summarize current knowledge on the effects of obesity and GDM on placental development and function. Understanding these processes is key in developing therapeutic interventions with the goal of mitigating these effects and preventing future cardiovascular and metabolic pathology in subsequent generations.


Wetlands ◽  
2021 ◽  
Vol 41 (6) ◽  
Author(s):  
Alba Cuena-Lombraña ◽  
Mauro Fois ◽  
Annalena Cogoni ◽  
Gianluigi Bacchetta

AbstractPlants are key elements of wetlands due to their evolutionary strategies for coping with life in a water-saturated environment, providing the basis for supporting nearly all wetland biota and habitat structure for other taxonomic groups. Sardinia, the second largest island of the Mediterranean Basin, hosts a great variety of wetlands, of which 16 are included in eight Ramsar sites. The 119 hydro- and hygrophilous vascular plant taxa from Sardinia represent the 42.6% and 37.9% of the number estimated for Italy and Europe, respectively. Moreover, around 30% of Sardinia’s bryological flora, which is made up of 498 taxa, is present in temporary ponds. An overview at regional scale considering algae is not available, to our knowledge, even though several specific studies have contributed to their knowledge. In order to find the most investigated research themes and wetland types, identify knowledge gaps and suggest recommendations for further research, we present a first attempt to outline the work that has been hitherto done on plants in lentic habitats in Sardinia. Three plant groups (algae, bryophytes and vascular plants), and five research themes (conservation, ecology, inventory, palaeobotany and taxonomy) were considered. After a literature review, we retained 202 papers published from 1960 to 2019. We found that studies on vascular plants, as plant group, were disproportionately more numerous, and inventories and ecology were the most investigated research themes. Although efforts have recently been made to fill these long-lasting gaps, there is a need for updating the existing information through innovative methods and integrative approaches.


Author(s):  
Władysława Wojciechowska ◽  
Tomasz Lenard

AbstractThe research was carried out in a mesotrophic and dimictic lake during winters with ice cover. In the last forty years, the development of phytoplankton was analyzed in five extreme winter seasons. The studies of phytoplankton characteristics in the water column took into account values of biomass, concentration of chlorophyll-a and species composition, including dominant species. Differences in the vertical distribution of flagellate and non-flagellate species belonging to cyanobacteria and algae were analyzed in the gradient of light and thermal conditions. The phytoplankton biomass was low and vertically differentiated, with the lowest values at the deeper part of the water column. Flagellate species from the group of Cryptophyceae, Chrysophyceae and Dinophyceae were most abundant. Species biodiversity was low but every winter the dominant species represented different taxonomic groups. In some periods, larger non-motile phytoplankton species from green or blue-green algae dominated. The research proved that the development of phytoplankton under the ice cover was limited mainly by light and, to a lesser extent, by temperature.


1991 ◽  
Vol 4 (3) ◽  
pp. 499 ◽  
Author(s):  
GI Jordan ◽  
RS Hill

Subtribe Banksiinae of the Proteaceae was diverse in Tasmania in the early and middle Tertiary, but is now restricted to two species, Banksia marginata and B. serrata. Rapid and extreme environmental changes during the Pleistocene are likely causes of the extinction of some Banksia species in Tasmania. Such extinctions may have been common in many taxonomic groups. The leaves and infructescences of Banksia kingii Jordan & Hill, sp. nov. are described from late Pleistocene sediments. This is the most recent macrofossil record of a now extinct species in Tasmania. Banksia kingii is related to the extant B. saxicola. Banksia strahanensis Jordan & Hill, sp. nov. (known only from a leaf and leaf fragments and related to B. spinulosa) is described from Early to Middle Pleistocene sediments in Tasmania. This represents the third Pleistocene macrofossil record of a plant species which is now extinct in Tasmania.


2010 ◽  
Vol 10 (4) ◽  
pp. 205-213 ◽  
Author(s):  
Silvana Masciadri ◽  
Ernesto Brugnoli ◽  
Pablo Muniz

In Uruguay, as well as in other regions of the world, IAS cause negative impacts on natural and managed ecosystems. The use of databases is a helpful tool to elaborate different strategies for prevention and control, and to develop policies and scientific analyses related to IAS. The database of IAS in Uruguay (InBUy) was developed during two time periods (2006-2007 and 2009-2010). It currently contains information on 33 specialists of different taxonomic groups, 14 research projects, 185 references, 351 species and 4,715 records, with vascular plants having both the highest number of species and records. Among vascular plants, herbaceous life forms are the most strongly represented, followed by trees and shrubs. Within animals, the fishes and mollusks are the most important groups. Analysis of the native distribution areas of IAS showed that most are indigenous from Europe, followed by Asia and Oceania. Data showed that introductions of IAS into Uruguay are mainly intentional (67%), so efforts should be focused on policies and rules in order to control the entrance of exotic organisms and prevent new invasions. The geography of the compiled dataset shows the main impact is along the coastline, where the highest exotic species richness and records occurs, and also the most biological invasions. The InBUy database is up-to-date and has successfully contributed to the creation of an official IAS list for Uruguay and both a National and a Coastal Geographic Information System. It has also been used for developing consciousness about this important threat to biodiversity, at both national and regional scales.


2011 ◽  
Vol 356-360 ◽  
pp. 903-907
Author(s):  
Ai Jun Li ◽  
Yan Ying Guo ◽  
Feng He ◽  
Rui Jia Yuan

There are few indicator systems available for monitoring and assessing the environmental quality of large-scale regions. We constructed an indicator system for integrated assessment of the environmental quality of the Dianchi Basin. First, the definition of regional environmental quality is determined by both the supply of materials and energy in the region and the extent to which the region is polluted. Second, the indicator categories used for assessment mainly comprise vegetation biomass and the concentrations of various pollutants. Third, owing to spatial heterogeneity of a region, evaluation of the regional environment first requires division into sub-regions, each of which should be relatively homogeneous with regard to physical conditions (e.g. marine and terrestrial) and appearance (e.g. vegetation cover). Finally, the mathematical models for assessing regional environmental quality can be built according to the relationships between the various indicators, the sub-regions and regional environmental quality. The indicator system built using this approach can reflect environmental changes over time and identifies reasons for environmental variation.


2017 ◽  
Vol 372 (1712) ◽  
pp. 20160036 ◽  
Author(s):  
Anna Kuparinen ◽  
Marco Festa-Bianchet

Commercial and recreational harvests create selection pressures for fitness-related phenotypic traits that are partly under genetic control. Consequently, harvesting can drive evolution in targeted traits. However, the quantification of harvest-induced evolutionary life history and phenotypic changes is challenging, because both density-dependent feedback and environmental changes may also affect these changes through phenotypic plasticity. Here, we synthesize current knowledge and uncertainties on six key points: (i) whether or not harvest-induced evolution is happening, (ii) whether or not it is beneficial, (iii) how it shapes biological systems, (iv) how it could be avoided, (v) its importance relative to other drivers of phenotypic changes, and (vi) whether or not it should be explicitly accounted for in management. We do this by reviewing findings from aquatic systems exposed to fishing and terrestrial systems targeted by hunting. Evidence from aquatic systems emphasizes evolutionary effects on age and size at maturity, while in terrestrial systems changes are seen in weapon size and date of parturition. We suggest that while harvest-induced evolution is likely to occur and negatively affect populations, the rate of evolutionary changes and their ecological implications can be managed efficiently by simply reducing harvest intensity. This article is part of the themed issue ‘Human influences on evolution, and the ecological and societal consequences'.


The Holocene ◽  
2018 ◽  
Vol 28 (8) ◽  
pp. 1266-1275 ◽  
Author(s):  
Kangkang Li ◽  
Xiaoguang Qin ◽  
Lei Zhang ◽  
Zhaoyan Gu ◽  
Bing Xu ◽  
...  

Human activity on arid lands has been related to oases evolution. The ancient Loulan, an important transportation hub of the ancient Silk Road, developed on an ancient oasis on the west bank of the lake Lop Nur in Xinjiang, China. Previous studies and historical documents suggest that the region has experienced dramatic natural environmental and human activity–related changes over time, transitioning from a particularly prosperous oasis to a depopulated zone with harsh environment after about 1500 a BP (before present, where present = AD 1950). Based on systematic radiocarbon (14C) dating for natural plant remains and archeological sites in the Loulan area, it was revealed that the region re-experienced oasis environment from 1260 to 1450 cal. AD, corresponding to the Yuan–Ming Dynasties, which is the climate transition stage from the ‘Medieval Warm Period’ to the ‘Little Ice Age’, encompassing a series of pulse-like flood events which cannot be identified from lacustrine deposition due to the limits of sampling resolution and dating. It was found that humans re-occupied the Loulan area and built canals to irrigate farmlands during the period. The more habitable hydrological conditions that resulted from these environmental changes present one major reason for the re-emergence of human activities in the Loulan area.


2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Alienor Jeliazkov ◽  
Darko Mijatovic ◽  
Stéphane Chantepie ◽  
Nigel Andrew ◽  
Raphaël Arlettaz ◽  
...  

AbstractThe use of functional information in the form of species traits plays an important role in explaining biodiversity patterns and responses to environmental changes. Although relationships between species composition, their traits, and the environment have been extensively studied on a case-by-case basis, results are variable, and it remains unclear how generalizable these relationships are across ecosystems, taxa and spatial scales. To address this gap, we collated 80 datasets from trait-based studies into a global database for metaCommunity Ecology: Species, Traits, Environment and Space; “CESTES”. Each dataset includes four matrices: species community abundances or presences/absences across multiple sites, species trait information, environmental variables and spatial coordinates of the sampling sites. The CESTES database is a live database: it will be maintained and expanded in the future as new datasets become available. By its harmonized structure, and the diversity of ecosystem types, taxonomic groups, and spatial scales it covers, the CESTES database provides an important opportunity for synthetic trait-based research in community ecology.


Water ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 1150 ◽  
Author(s):  
Mehrnoosh Ghadimi ◽  
Sasan Zangenehtabar ◽  
Shahin Homaeigohar

Nanomaterials, i.e., those materials which have at least one dimension in the 1–100 nm size range, have produced a new generation of technologies for water purification. This includes nanosized adsorbents, nanomembranes, photocatalysts, etc. On the other hand, their uncontrolled release can potentially endanger biota in various environmental domains such as soil and water systems. In this review, we point out the opportunities created by the use of nanomaterials for water remediation and also the adverse effects of such small potential pollutants on the environment. While there is still a large need to further identify the potential hazards of nanomaterials through extensive lab or even field studies, an overview on the current knowledge about the pros and cons of such systems should be helpful for their better implementation.


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