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A revision of the family Sematophyllaceae (Bryophyta) in southern Africa

Abstract

In the Flora of southern Africa area, comprising the countries of South Africa, Namibia, Botswana, Lesotho and Swaziland, the moss family Sematophyllaceae consists of three genera (Trichosteleum, Donnellia and Sematophyllum) and nine species. Core sematophyllous taxa with collenchymatous exothecial cells, long rostrate operculum, linear leaf cells and differentiated alar cells are included in the family. Meiothecium fuscescens is transferred to Donnellia and a new combination made. Sematophyllum wageri is reduced to synonymy under S. brachycarpum and a lectotype is designated for S. dregei. Each species is described and its distribution mapped.

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Two new species of Lejeuneaceae tribe Lejeuneeae (Marchantiophyta) from Colombia

Abstract

We describe the new liverwort species Lejeunea ryszardii from montane rainforest in the Central Cordillera of Colombia (Dept. Quindío) and Rectolejeunea halinae from submontane rainforest in the Western Cordillera (Dept. Risaralda). Both species stand out by copious vegetative reproduction via caducous leaves. Lejeunea ryszardii resembles the Caribbean L. paucidentata in the leaf lobes with toothed margins and a narrow base but strikingly differs from the latter species in: 1) leaf margins with mamillose cells, which are sometimes crowned by a small papilla, and with scattered rhizoids with or without a tooth-like base; 2) lobules with narrowly elongate, curved, sharp tooth; 3) stem epidermis brownish and somewhat thick-walled; 4) copious production of caducous leaf lobes. Moreover, L. ryszardii is dark green to brown in color and probably dioicous while L. paucidentata is light green and autoicous. Rectolejeunea halinae resembles the neotropical R. flagelliformis in having ciliate caducous leaves but clearly differs from the latter in the pointed leaf tips, the presence of ocelli in underleaves, and the flagelliform shoots with flat, entire-margined underleaves. The discovery of these new species adds two further endemic taxa to the rich bryophyte flora of the Colombian Andes.

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Carbon Leakage in the context of increasing the EU greenhouse gas emission reduction targets – the ways the EU and global emission behave and what influences its scale

Abstract

The lack of equal globally binding GHG’s emission reduction targets is currently leading to a set of diverging GHG’s emission prices across the world (or even no price for GHG’s emission in some regions). This may result in distortions with direct implications on competitiveness of the industries in regions with strict climate policies (as the European Union) and can cause the issue of carbon leakage. Carbon leakage is defined as ‘the increase in emission outside a region as a direct result of the policy to cap emission in this region’.

This paper is the first part of the set of two analysis aiming at the carbon leakage assessment. In the following paper (aimed to be published this year), we will assess the impact of free allowances for emission intensive trade exposed industries (EITE) and the NDCs in the rest of the world countries – for the sake of brevity, we decided to remove these results from the current paper, but they will be presented later this year. The purpose of this paper is to assess the possible scale of the carbon leakage using different assumptions and policy scenarios and identify channels to efficiently prevent the carbon leakage phenomenon. The analysis has been carried out using the computable general equilibrium d-PLACE model developed within the Centre for Climate and Policy Analysis (CAKE). 1 Our model is a recursive dynamic multi-regional and multi-commodity tool in which emissions are modelled in great detail, for example, the process and each fossil fuel combustion related emission are modelled separately. Furthermore, the big advantage of the applied model is a very detailed modelling of EU ETS as well as non-ETS emission targets. In the paper, the simulations using two versions of model was presented – with and without endogenous technical change to elaborate on how the assumptions on technical change affect the modelling results and consequent scale of the carbon leakage. Moreover, this paper aims mainly at the assessment of different channels of carbon leakage; therefore, we do not take into account either NDCs in the rest of the world or free allowances for emission intensive trade exposed sectors. These problems will be handled in the next paper, aimed to be published later this year.

Using the above mentioned CGE (computable general equilibrium model, we captured the main factors, that determine the carbon leakage rates. We assessed the contribution of three channels – demand channel, competitiveness channel and carbon intensity channel to the risk of carbon leakage. It turned out that carbon intensity channel and competitiveness channel are the most important, while demand channel contributes to changes in GHG’s emission only in the most restrictive scenario. Moreover, energy channel was further decomposed to the impact of sectoral structure and influence in emission intensity within each sector – the impact of these two channels is also similar, but dependent on the analysed scenario. Such a decomposition allowed us to determine the main channels through which the carbon leakage occur and pursue relevant policy recommendations.

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Herpetofauna of the Pieprzowe Mountains Nature Reserve and adjacent areas

Abstract

The study was focused on determining the sites of amphibian and reptile occurrence in the Pieprzowe Mountains Nature Reserve (area 18.01 ha) and adjacent areas (total area 58.81 ha). The investigations also involved the biology of breeding in the selected species, as well as determining threats and protection measures.

Situated in the eastern part of the Świętokrzyskie Voivodeship, the steppe-like Pieprzowe (Pepper) Mountains Nature Reserve was established in 1979. Its aim is to protect xerothermic assemblages inhabited by many species of rare plants including the largest European aggregation of roses growing wild. The area is located on a steep, sometimes rugged escarpment, which is part of the Vistula River erosional margin. The escarpment exposes Cambrian black pepper-like shales. The slope base is overgrown by a narrow belt of willow thickets. Above occur assemblages of xerothermic thickets with a few trees. The highest parts of the nature reserve are overgrown with xerothermic grasslands with the prevalence of feathergrass steppe (Festuco-Stipion class). The reserve is surrounded by riparian forests, waterlogged meadows and reservoirs of the Vistula former riverbed, the largest of which is an oxbow lake (5.16 ha).

The following species were documented in 2016-2017: smooth newt Lissotriton vulgaris L., great crested newt Triturus cristatus Laur., European fire-bellied toad Bombina bombina L., common toad Bufo bufo L., European green toad Bufotes viridis Laur., European tree frog Hyla arborea L., edible frog Pelophylax esculentus L., pool frog Pelophylax lessonae Cam., marsh frog Pelophylax ridibundus Laur., moor frog Rana arvalis Nilss., common frog Rana temporaria L., sand lizard Lacerta agilis L., grass snake Natrix natrix L. and common European adder Vipera berus L. The studies were focused on biology of breeding and phenology in common toad and common frog.

The main threats posed on herpetofauna include: human presence, littering, fire raising and changes of water balance.

© IOŚ-PIB

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Herpetofauna of the Podkielecki Landscape Protection Area

Abstract

The study was conducted in 2016-2017 in the Podkielecki Landscape Protection Area (area 26,485 ha). It was focused on the occurrence and distribution of amphibians and reptiles, the biology of the selected species and the existing threats.

Established in 1995, the Podkielecki Landscape Protection Area surrounds the city of Kielce from the north, east and south-east, and adjoins several other protected areas. It covers the western part of the Świętokrzyskie Mountains (part of the Klonowskie and Masłowskie ranges) and the southern part of the Suchedniów Plateau. The studied area is mostly covered by forest and thicket communities (48.1%) and farmlands (39.9%), followed by built-up areas (7.8%), industrial areas (0.5%), roads and railways (2.7%), and surface water bodies (1%).

The protected area is developed mainly on Palaeozoic rocks, including Cambrian and Ordovician sandstones, Silurian and Carboniferous shales, and Devonian marls. Podzolic soils predominate among soils. The largest rivers include Lubrzanka, Czarna Nida, Bobrza and Belnianka. There are no natural lakes within the PLPA limits, and the largest artificial reservoirs include the Cedzyna Reservoir, Morawica Reservoir, Suków Sandpit and two sedimentation reservoirs of the Kielce Power Plant. The area includes 2 nature reserves: Barcza and Sufraganiec.

The following amphibian species were recognised during the investigations within the borders of the studied area: alpine newt Ichthyosaura alpestris Laur., great crested newt Triturus cristatus Laur., smooth newt Lissotriton vulgaris L., European fire-bellied toad Bombina bombina L., common spadefoot toad Pelobates fuscus Laur., common toad Bufo bufo L., natterjack toad Epidalea calamita Laur., European green toad Bufotes viridis Laur., European tree frog Hyla arborea L., pool frog Pelophylax lessonae Cam., edible frog Pelophylax esculentus L., marsh frog Pelophylax ridibundus Pall., moor frog Rana arvalis Nilss., and common frog Rana temporaria L. The reptiles were represented by sand lizard Lacerta agilis L., viviparous lizard Zootoca vivipara Jacquin, slow worm Anguis fragilis L., grass snake Natrix natrix L. and common European adder Vipera berus L. The study also included the phenology and breeding biology of the common toad and common frog.

The most crucial herpetofauna conservation problems identified here include amphibians killed on roads by vehicles. The study area is intersected by very busy roads, in particular: European route no. E77, national roads nos. 73, 74 and S74, and regional roads nos. 745, 750 and 764. For this reason, future road reconstruction projects should consider the assembly of various crossing roads for wildlife, particularly on the 600 m long section of national road no. 74 near Cedzyna Reservoir. Other threats include illegal waste dumping, pollution of surface waters, fire setting, overgrowing and desiccation of small water bodies.

© IOŚ-PIB

Open access
Indicators of peat soil degradation in the Biebrza valley, Poland

Abstract

Peat mineralisation leads to net loss of CO2 to the atmosphere, as well as to release of other elements from the decomposed soil organic matter (SOM) to groundwater. This results in the degradation of peat soils and the ecosystems they support. Here we evaluated the practical indicatory suitability of the existing and proposed new indices for the assessment of peat soil degradation in the Biebrza river valley encompassing, unique on European scale, peatland ecosystems. We studied relationships between soil organic carbon (SOC) and total nitrogen (Ntot), dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) in a series of degraded peat soils in the Biebrza valley. Samples were taken from soils developed on peat deposits that varied in thickness and the degree of peat decomposition, from undegraded to highly mineralised peats. The relationships between changes in the SOC content and changes in the values of the remaining variables (SOM, Ntot, DOC, DON, C/N ratio), were statistically tested. Linear and non-linear regressions were used to establish the relationships amongst the variables examined. The losses of soil C and N occur independently and differ between stages of peat soil mineralisation. From our study, it results that the peat mineralisation intensity may be estimated based on the loss of SOC. We found that 1% loss of SOC corresponded to 1.028% loss of SOM, regardless of the degree of peat soil mineralisation, whereas SOM solubility, measured by the content of DOC, varied based on the intensity of peat soil mineralisation. The content of DOC decreased with the decrease in the SOC content, whereas the DOC/ SOC ratio increased depending on the intensity of peat decomposition. The C/N ratio is not a reliable indicator of peat mineralisation, because its values are driven not only by the nitrogen natively present in peat soils but also by nitrogen from external sources. The contents of SOC and Ntot did not decrease uniformly during peat decomposition because C and N show various mobility in the processes of SOM mineralisation. We found that the DOC/SOC ratio was most indicative of peat soil mineralisation intensity.

© IOŚ-PIB

Open access
The role and significance of stingless bees (Hymenoptera: Apiformes: Meliponini) in the natural environment

Abstract

This article refers to the biology and ecology of stingless bees (Meliponini), living in tropical and subtropical areas. Similar to honey bees (Apis mellifera), stingless bees (Meliponini) belong to the category of proper social insects and are at the highest level of social development. This group of insects comprises about 500 species and they are the most common bees pollinating the native plants in many tropical areas. Families of stingless bees are usually quite numerous, reaching up to 100,000 individuals. They are characterised by polymorphism, age polyethism and perennialism. This article presents the structural complexity of natural nesting of these tropical insects and their ability to settle in artificial nest traps. The main significance of stingless bees for humans is their role in the natural environment as pollinators, which is an essential factor influencing biodiversity.

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Anisotropie der gesättigten Wasserleitfähigkeit in Böden der Hauptnaturräume Schleswig-Holsteins (Norddeutschland) unter Acker- und Grünlandnutzung

Zusammenfassung

Gegenwärtig diskutierte Phänomene, wie häufig auftretender Oberflächenabfluss, vermehrte Bodenerosion und verringerte Ertragssicherheit, lassen sich ansatzweise über Bodenstruktureigenschaften und eine daraus hervorgehende, räumlich unterschiedlich gesättigte Wasserleitfähigkeit des Bodens erklären. Hierzu wurden Datensätze aus 766 Profilen unter Acker- und Grünlandnutzung in den vier Hauptnaturräumen Schleswig Holsteins (Östliches Hügelland, Niedere und Hohe Geest sowie Marsch) zur gesättigten Wasserleitfähigkeit (kf) in vertikaler und horizontaler Richtung und damit deren Richtungsabhängigkeit (Anisotropie) bis in eine Tiefe von 60 cm untersucht. Die Ergebnisse zeigen eine verstärkte Anisotropie der kf in horizontaler Richtung an, die jedoch in Abhängigkeit vom geologischen Ausgangsgestein, Bodentyp und Tongehalt sowie von der Landnutzung variiert. Unter Ackernutzung weisen die Unterböden aller Hauptnaturräume im Mittel eine horizontale Anisotropie auf, die unterhalb der Pflugsohle (≤ 40 cm Tiefe) am stärksten ausgeprägt ist und auf Plattenstrukturbildungen als Folge der Bodenbewirtschaftung hindeuten. Unter Grünlandnutzung zeigen besonders die Oberböden eine horizontale Anisotropie, wobei diese in den beiden Geestregionen mit einem hohen Anteil an Viehwirtschaft auch im Unterboden sehr ausgeprägt ist. Anisotropieeffekte, insbesondere im Unterboden unter Ackernutzung, deuten sich auch bodentypspezifisch für Kolluvisole, Pseudogley-Parabraunerden und Pseudogleye an. Deren hohe Empfindlichkeit gegenüber anthropogenen Strukturänderungen (Plattenbildung) spiegelt sich im zeitlichen Verlauf der horizontalen kf wider, die über die letzten 30 Jahre im Östlichen Hügelland signifikant zugenommen hat.

Open access
Compared impact of compost and digestate on priming effect and hydrophobicity of soils depending on textural composition

Summary

Digestates and compost are used as valuable fertilizers in agriculture because of their benefits for plant nutrition and carbon sequestration potential. These amendments are also suspected to interfere negatively with the soil. To compare their relevance for priming effect and hydrophobicity of soils, two amounts of digestate or compost, respectively, were mixed with a homogenized cambic Luvisol and a Podzol. The basal respiration rate (BAS), the repellency index (RI) and organic carbon content (Corg) of pre-dried mixtures were investigated. The podsolic mixture showed quantitative reduction of Corg and increased BAS (this effect was not statistically significant) due to priming effect through microbial stimulation. As a result of enhanced organic substance (OS) protection in the cambic Luvisol mixture, constant amounts of Corg and declined BAS could be detected. The wettability was reduced in both soils: either directly by the supply of amphiphilic components or indirectly by increased incorporation of microbial exudates. This reduction was not statistically significant. Higher contents of available organic compounds in digestates and higher amounts of hydrophobic humic acids in the compost could be assumed to be decisive for generation of hydrophobicity. Also the soil texture controlled the microbial decomposition by higher incorporation of OS in finer pores and contributed to the protection against microbial decay.

Open access
Methods to describe the botanical composition of vegetation in grassland research

Summary

In terms of botanical composition, grassland vegetation in experimental plots and field studies can be described by means of different parameters (plant density, cover, frequency or yield proportion). Each parameter describes different features, which under certain circumstances may be correlated one to each other to some extent, but are not fully equivalent. The choice of the parameter to be assessed depends therefore, in first instance, on the specific aim of the investigation. For the assessment of the chosen parameter, many methods are available that differ from each other in terms of subjectivity, precision, effort and requirement for technical equipment. The choice of method depends mainly on the required precision, the affordable effort and on the available resources.

Open access