Formation of a cultivated spodosol in east-central Finland

The processes involved in Spodosol (Podzol) formation are still being debated. The pedogenic processes in a Spodosol, 10,700 years-old, at Sotkamo that has been cultivated for about 50 years were studied by characterizing the morphology and analyzing the major chemical properties, texture and mineralogy. Before cultivation, organic acids produced by decomposition of organic matter from pine litter in O and A horizons had weathered primary minerals in A and E horizons releasing Al and Fe. Percolating waters moved the organo-metallic complexes from A and E horizons to Bhsm and Bs horizons where the complexes coated and bridged sand grains eventually forming cemented ortstein. Because of the high biotite content of the parent material, the index of accumulation of Fe and Al in the Bhsm horizon (Al + 0.5 Fe = 4.1%) was the highest reported in Spodosols of Finland. The data support the theory of downward movement of Al and Fe as organo-metallic complexes with formation of some ferrihydrite but little or no formation of imogolite type materials. Little, if any, podzolization has likely occurred since the initiation of cultivation because, after agricultural liming and consequent increase of pH in the Ap horizon, organic compounds are likely to chelate Ca and Mg rather than Al and Fe.;Karkeille hietamaille syntyneet podsolit ovat Suomen kehittyneimpiä maannoksia. Niitä tutkimalla saadaan uutta tietoa tämän koko pohjoisella havumetsävyöhykkeelläyleisen maannostyypin kehittymiseen johtaneista prosesseista, joista edelleenkin vallitsee erilaisia käsityksiä. Tämän tutkimuksen kohteena oli Sotkamossa karkealla hietamaalla oleva noin 50 vuotta viljelty maa, joka on ollut kuivillaan noin 10 700 vuotta. Muokkauskerroksen alapuolella oli huuhtoutumiskerros (valkomaa), joka sisälsi lähes pelkkää kvartsihiekkaa. Sen alapuolella oli noin 10 cm paksu rautapalsi eli iskostunut horisontti, johon ylempää orgaanisina kompleksiyhdisteinä huuhtoutuneet rauta ja alumiini ovat saostuneet. Mikroskoopilla voidaan nähdä, miten nämä saostuneet ainesosat peittävät kvartsihiekan jyväset ja sitovat ne yhteen. Tässä horisontissa oli erittäin runsaasti heikosti kiteytynyttä rautaoksidia, joka on uutettavissa ammoniumoksalaattiliuoksella, kun taas valkomaassa tällaista rautaa oli erittäin vähän. Rikastumiskerroksen alumiinista valtaosa oli pyrofosfaattiin uuttuvassa, oletettavasti orgaanisen aineksen sitomassa muodossa, mikä viittaa aineiden kulkeutuneen tähän horisonttiin nimenomaan kelaatteina eikä epäorgaanisina kolloideina. Syvä kyntö on nostanut valkomaata ja kappaleita rikastumiskerroksen iskostumasta myös muokkauskerrokseen. Rikastumiskerroksen alapuolella kvartsihiekkajyvästen pinnoilla ei ollut paljonkaan rautasaostumia, mutta mikroskoopilla näkyi runsaasti rapautumatonta biotiittia. Rikastumiskerroksen rauta lienee suureksi osaksi peräisin juuri biotiitista, joka on kokonaisuudessaan rapautunut pintamaasta. Vähemmän biotiittia sisältäviin maihin ei todennäköisesti kehity näin vahvaa rikastumiskerrosta maan pienemmän rautapitoisuuden takia. Podsoloituminen on luultavasti pysähtynyt sen jälkeen, kun maa on otettu viljelyyn ja sen pintaosien pH on kalkituksen seurauksena noussut

Efficient plot-based floristic assessment of tropical forests

The tropical flora remains chronically understudied and the lack of floristic understanding hampers ecological research and its application for large-scale conservation planning. Given scarce resources and the scale of the challenge there is a need to maximize the efficiency of both sampling strategies and sampling units, yet there is little information on the relative efficiency of different approaches to floristic assessment in tropical forests. This paper is the first attempt to address this gap. We repeatedly sampled forests in two regions of Amazonia using the two most widely used plot-based protocols of floristic sampling, and compared their performance in terms of the quantity of floristic knowledge and ecological insight gained scaled to the field effort required. Specifically, the methods are assessed first in terms of the number of person-days required to complete each sample (‘effort’), secondly by the total gain in the quantity of floristic information that each unit of effort provides (‘crude inventory efficiency’), and thirdly in terms of the floristic information gained as a proportion of the target species pool (‘proportional inventory efficiency’). Finally, we compare the methods in terms of their efficiency in identifying different ecological patterns within the data (‘ecological efficiency’) while controlling for effort. There are large and consistent differences in the performance of the two methods. The disparity is maintained even after accounting for regional and site-level variation in forest species richness, tree density and the number of field assistants. We interpret our results in the context of selecting the appropriate method for particular research purposes

Formation of a cultivated spodosol in east-central Finland

The processes involved in Spodosol (Podzol) formation are still being debated. The pedogenic processes in a Spodosol, 10,700 years-old, at Sotkamo that has been cultivated for about 50 years were studied by characterizing the morphology and analyzing the major chemical properties, texture and mineralogy. Before cultivation, organic acids produced by decomposition of organic matter from pine litter in O and A horizons had weathered primary minerals in A and E horizons releasing Al and Fe. Percolating waters moved the organo-metallic complexes from A and E horizons to Bhsm and Bs horizons where the complexes coated and bridged sand grains eventually forming cemented ortstein. Because of the high biotite content of the parent material, the index of accumulation of Fe and Al in the Bhsm horizon (Al + 0.5 Fe = 4.1%) was the highest reported in Spodosols of Finland. The data support the theory of downward movement of Al and Fe as organo-metallic complexes with formation of some ferrihydrite but little or no formation of imogolite type materials. Little, if any, podzolization has likely occurred since the initiation of cultivation because, after agricultural liming and consequent increase of pH in the Ap horizon, organic compounds are likely to chelate Ca and Mg rather than Al and Fe.

Suomen viljelymaiden pedologisia piirteitä ja maannoksia

ei saatavill

Regenerative Medicine and the Developing World

This is the first study to systematically identify and prioritize which applications of regenerative medicine are the most promising for improving health in developing countries

Phenol-Soluble Modulin α Peptide Toxins from Aggressive Staphylococcus aureus Induce Rapid Formation of Neutrophil Extracellular Traps through a Reactive Oxygen Species-Independent Pathway

Neutrophils have the ability to capture and kill microbes extracellularly through the formation of neutrophil extracellular traps (NETs). These are DNA and protein structures that neutrophils release extracellularly and are believed to function as a defense mechanism against microbes. The classic NET formation process, triggered by, e.g., bacteria, fungi, or by direct stimulation of protein kinase C through phorbol myristate acetate, is an active process that takes several hours and relies on the production of reactive oxygen species (ROS) that are further modified by myeloperoxidase (MPO). We show here that NET-like structures can also be formed by neutrophils after interaction with phenol-soluble modulin α (PSMα) that are cytotoxic membrane-disturbing peptides, secreted from community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA). The PSMα-induced NETs contained the typical protein markers and were able to capture microbes. The PSMα-induced NET structures were disintegrated upon prolonged exposure to DNase-positive S. aureus but not on exposure to DNase-negative Candida albicans. Opposed to classic NETosis, PSMα-triggered NET formation occurred very rapidly, independently of ROS or MPO, and was also manifest at 4°C. These data indicate that rapid NETs release may result from cytotoxic membrane disturbance by PSMα peptides, a process that may be of importance for CA-MRSA virulence

Evaluation of Southern Ocean cloud in the HadGEM3 general circulation model and MERRA-2 reanalysis using ship-based observations

Southern Ocean (SO) shortwave (SW) radiation biases are a common problem in contemporary general circulation models (GCMs), with most models exhibiting a tendency to absorb too much incoming SW radiation. These biases have been attributed to deficiencies in the representation of clouds during the austral summer months, either due to cloud cover or cloud albedo being too low. The problem has been the focus of many studies, most of which utilised satellite datasets for model evaluation. We use multi-year ship-based observations and the CERES spaceborne radiation budget measurements to contrast cloud representation and SW radiation in the atmospheric component Global Atmosphere (GA) version&nbsp;7.1 of the HadGEM3 GCM and the MERRA-2 reanalysis. We find that the prevailing bias is negative in GA7.1 and positive in MERRA-2. GA7.1 performs better than MERRA-2 in terms of absolute SW bias. Significant errors of up to 21&thinsp;W&thinsp;m&minus;2 (GA7.1) and 39&thinsp;W&thinsp;m&minus;2 (MERRA-2) are present in both models in the austral summer. Using ship-based ceilometer observations, we find low cloud below 2&thinsp;km to be predominant in the Ross Sea and the Indian Ocean sectors of the SO. Utilising a novel surface lidar simulator developed for this study, derived from an existing Cloud Feedback Model Intercomparison Project (CFMIP) Observation Simulator Package (COSP) &ndash; active remote sensing simulator (ACTSIM) spaceborne lidar simulator, we find that GA7.1 and MERRA-2 both underestimate low cloud and fog occurrence relative to the ship observations on average by 4&thinsp;%&ndash;9&thinsp;% (GA7.1) and 18&thinsp;% (MERRA-2). Based on radiosonde observations, we also find the low cloud to be strongly linked to boundary layer atmospheric stability and the sea surface temperature. GA7.1 and MERRA-2 do not represent the observed relationship between boundary layer stability and clouds well. We find that MERRA-2 has a much greater proportion of cloud liquid water in the SO in austral summer than GA7.1, a likely key contributor to the difference in the SW radiation bias. Our results suggest that subgrid-scale processes (cloud and boundary layer parameterisations) are responsible for the bias and that in GA7.1 a major part of the SW radiation bias can be explained by cloud cover underestimation, relative to underestimation of cloud albedo.</p

COMPARE Forum: The idea of North-South and South-South collaboration

The idea of having a Compare Forum focusing on the above title was first discussed with one of the Editors of Compare during a PhD defence in Oslo in 2011. The PhD dissertation itself was linked to a larger project in which researchers from the North (Norway) and the South (South Africa) had been collaborating in educational research for over 10 years. Despite the fact that North-South collaboration is not a new issue on the agenda (King 1985) it is still a timely topic to explore, particularly given the recent growth and moves towards North-South-South collaboration or even South-South Cooperation in Education and Development (Chisholm and Steiner-Khamsi 2009). Thus, any discussion of research collaboration, whether North-South or South-South, is seen as an ideal topic for comparative education, particularly when exploring why there should be collaboration at all and if so what are some of the challenges. While it may be argued that the difference between North-South and South-South collaboration may simply be a question of geography, King (1985) reminds us that collaboration is not necessarily between equals and that collaboration at times ‘appears to be a process initiated in the North, and in which the South participates, as a counterpart’ (184). Ultimately, the differences go beyond simple geographic location to issues of funding and power, something that each of the contributions will touch upon in their own way. While cooperation may mean working with someone, it does suggest that one partner provides information or resources to the other, while collaboration suggests a more equal partnership in which researchers work alongside each other. For the majority of our contributors, we use collaboration as opposed to cooperation, although the literature is not always so clear on this distinction.Web of Scienc