scholarly journals How big is the influence of biogenic silicon pools on short-term changes in water-soluble silicon in soils? Implications from a study of a 10-year-old soil–plant system

2017 ◽  
Vol 14 (22) ◽  
pp. 5239-5252 ◽  
Author(s):  
Daniel Puppe ◽  
Axel Höhn ◽  
Danuta Kaczorek ◽  
Manfred Wanner ◽  
Marc Wehrhan ◽  
...  
Keyword(s):  
Water Soluble ◽  
Small Scale ◽  
Testate Amoeba ◽  
Short Term ◽  
Plant Materials ◽  
Main Driver ◽  
Key Factor ◽  
Calamagrostis Epigejos ◽  
Biogenic Silicon ◽  
Future Work

Abstract. The significance of biogenic silicon (BSi) pools as a key factor for the control of Si fluxes from terrestrial to aquatic ecosystems has been recognized for decades. However, while most research has been focused on phytogenic Si pools, knowledge of other BSi pools is still limited. We hypothesized that different BSi pools influence short-term changes in the water-soluble Si fraction in soils to different extents. To test our hypothesis we took plant (Calamagrostis epigejos, Phragmites australis) and soil samples in an artificial catchment in a post-mining landscape in the state of Brandenburg, Germany. We quantified phytogenic (phytoliths), protistic (diatom frustules and testate amoeba shells) and zoogenic (sponge spicules) Si pools as well as Tiron-extractable and water-soluble Si fractions in soils at the beginning (t0) and after 10 years (t10) of ecosystem development. As expected the results of Tiron extraction showed that there are no consistent changes in the amorphous Si pool at Chicken Creek (Hühnerwasser) as early as after 10 years. In contrast to t0 we found increased water-soluble Si and BSi pools at t10; thus we concluded that BSi pools are the main driver of short-term changes in water-soluble Si. However, because total BSi represents only small proportions of water-soluble Si at t0 (< 2 %) and t10 (2.8–4.3 %) we further concluded that smaller (< 5 µm) and/or fragile phytogenic Si structures have the biggest impact on short-term changes in water-soluble Si. In this context, extracted phytoliths (> 5 µm) only amounted to about 16 % of total Si contents of plant materials of C. epigejos and P. australis at t10; thus about 84 % of small-scale and/or fragile phytogenic Si is not quantified by the used phytolith extraction method. Analyses of small-scale and fragile phytogenic Si structures are urgently needed in future work as they seem to represent the biggest and most reactive Si pool in soils. Thus they are the most important drivers of Si cycling in terrestrial biogeosystems.

scholarly journals How big is the influence of biogenic silicon pools on short-term changes of water soluble silicon in soils? Implications from a study of a ten-year-old plant-soil-system

2017 ◽  
Author(s):  
Daniel Puppe ◽  
Axel Höhn ◽  
Danuta Kaczorek ◽  
Manfred Wanner ◽  
Marc Wehrhan ◽  
...  
Keyword(s):  
Water Soluble ◽  
Testate Amoeba ◽  
Short Term ◽  
Soil System ◽  
Plant Soil ◽  
Main Driver ◽  
Key Factor ◽  
Calamagrostis Epigejos ◽  
Biogenic Silicon ◽  
Soluble Silicon

Abstract. The significance of biogenic silicon (BSi) pools as a key factor for the control of Si fluxes from terrestrial to aquatic ecosystems has been recognized since decades. However, while most research has been focused on phytogenic Si pools, knowledge on other BSi pools is still limited. We hypothesized different BSi pools to influence short-term changes of the water soluble Si fraction in soils to different extents. To test our hypothesis we took plant (Calamagrostis epigejos, Phragmites australis) and soil samples in an artificial catchment in a post-mining landscape in the state of Brandenburg, Germany. We quantified phytogenic (phytoliths), protistic (diatom frustules and testate amoeba shells) and zoogenic (sponge spicules) Si pools as well as Tiron extractable and water soluble Si fractions in soils at the beginning (t0) and after ten years (t10) of ecosystem development. As expected the results of Tiron extraction showed, that there are no consistent changes of the amorphous Si pool at Chicken Creek as early as after ten years. In contrast, compared to t0 we found increased water soluble Si and BSi pools at t10, thus we concluded BSi pools to be the main driver of short-term changes of water soluble Si. However, because total BSi represents only small proportions of water soluble Si at t0 (

scholarly journals Measuring Men’s Gender Norm Beliefs Related to Contraception: Development of the Masculine Norms and Family Planning Acceptance Scale

2021 ◽  
Author(s):  
Sara J. Newmann ◽  
Jennifer Monroe Zakaras ◽  
Shari L. Dworkin ◽  
Mellissa Withers ◽  
Louisa Ndunyu ◽  
...  
Keyword(s):  
Family Planning ◽  
Contraceptive Use ◽  
Gender Norms ◽  
Male Partner ◽  
Masculine Norms ◽  
Pregnancy Spacing ◽  
Key Factor ◽  
Acceptance Scale ◽  
Future Work ◽  
Positive Engagement

AbstractMale partner resistance is identified as a key factor that influences women’s contraceptive use. Examination of the masculine norms that shape men’s resistance to contraception—and how to intervene on these norms—is needed. To assess a gender-transformative intervention in Kenya, we developed and evaluated a masculinity-informed instrument to measure men’s contraceptive acceptance—the Masculine Norms and Family Planning Acceptance (MNFPA) scale. We developed draft scale items based on qualitative research and administered them to partnered Kenyan men (n = 150). Item response theory-based methods were used to reduce and psychometrically evaluate final scale items. The MNFPA scale had a Cronbach’s α of 0.68 and loaded onto a single factor. MNFPA scores were associated with self-efficacy and intention to accept a female partner’s use of contraception; scores were not associated with current contraceptive use. The MNFPA scale is the first rigorously developed and psychometrically evaluated tool to assess men’s contraceptive acceptance as a function of male gender norms. Future work is needed to test the MNFPA measure in larger samples and across different contexts. The scale can be used to evaluate interventions that seek to shift gender norms to increase men’s positive engagement in pregnancy spacing and prevention.

The effect of nitrogen fertilizers on the ensiling characteristics of perennial ryegrass and cocksfoot

1970 ◽  
Vol 75 (3) ◽  
pp. 517-521 ◽  
Author(s):  
D. I. H. Jones
Keyword(s):  
Perennial Ryegrass ◽  
Matter Content ◽  
Buffering Capacity ◽  
N Fertilizer ◽  
Water Soluble ◽  
Nitrogen Fertilizers ◽  
Soluble Carbohydrates ◽  
Small Scale ◽  
Dry Matter Content ◽  
Growing Seasons

SUMMARYThe effect of three levels of N fertilizer on the ensiling characteristics of S. 24 perennial ryegrass and S. 37 cocksfoot have been examined during first growth in two growing seasons. The effects of sucrose supplementation, inoculation with Lactobacillus plantarum and wilting were also examined in certain cuts. All silages were made in the laboratory using a small scale vacuum silage technique.The perennial ryegrass herbage was higher in water soluble carbohydrates than the cocksfoot, N fertilizers decreased soluble carbohydrates and dry-matter content in both species. Buffering capacity was not consistently different between grasses or between N levels.Herbage was cut at two stages of maturity in the first year. In the first cut (8 days before ear emergence), perennial ryegrass silages were well preserved irrespective of the amount of N applied to the grass. Cocksfoot silages were well preserved only when the lowest level of N fertilizer had been applied (50 kg/ha). Supplementation of cocksfoot with sucrose prior to ensiling markedly improved silage quality, but inoculation had no effect. In the second cut (26 days after ear emergence) the grasses were higher in drymatter content and showed a lower buffering capacity, but neither ryegrass nor cocksfoot silages were well preserved unless supplemented with sucrose prior to ensiling.In the second year of the experiment only one cut was taken (9 days after ear emergence). As in the previous year, silages made from herbage at a late stage of growth were poorly preserved. Wilting prior to ensiling resulted in well-preserved silages.It is concluded that the need for additives and wilting to ensure satisfactory preservation varies in relation to the variety of grass used and its stage of growth.

Interlaboratory Validation of Small-Scale Solubility and Dissolution Measurements of Poorly Water-Soluble Drugs

2016 ◽  
Vol 105 (9) ◽  
pp. 2864-2872 ◽  
Author(s):  
Sara B.E. Andersson ◽  
Caroline Alvebratt ◽  
Jan Bevernage ◽  
Damien Bonneau ◽  
Claudia da Costa Mathews ◽  
...  
Keyword(s):  
Water Soluble ◽  
Small Scale ◽  
Poorly Water Soluble Drugs ◽  
Water Soluble Drugs ◽  
Interlaboratory Validation ◽  
Poorly Water Soluble

Short-term responses of plants and invertebrates to experimental small-scale grassland fragmentation

Oecologia ◽  
2000 ◽  
Vol 125 (4) ◽  
pp. 559-572 ◽  
Author(s):  
Samuel Zschokke ◽  
Claudine Dolt ◽  
Hans-Peter Rusterholz ◽  
Peter Oggier ◽  
Brigitte Braschler ◽  
...  
Keyword(s):  
Small Scale ◽  
Short Term

scholarly journals An On-Line Low-Cost Irradiance Monitoring Network with Sub-Second Sampling Adapted to Small-Scale PV Systems

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3405 ◽  
Author(s):  
Manuel Espinosa-Gavira ◽  
Agustín Agüera-Pérez ◽  
Juan González de la Rosa ◽  
José Palomares-Salas ◽  
José Sierra-Fernández
Keyword(s):  
Sensor Networks ◽  
Low Cost ◽  
Monitoring Network ◽  
Absolute Error ◽  
Small Scale ◽  
Photovoltaic Systems ◽  
Real Time Control ◽  
Short Term ◽  
Time Control ◽  
Cloud Motion

Very short-term solar forecasts are gaining interest for their application on real-time control of photovoltaic systems. These forecasts are intimately related to the cloud motion that produce variations of the irradiance field on scales of seconds and meters, thus particularly impacting in small photovoltaic systems. Very short-term forecast models must be supported by updated information of the local irradiance field, and solar sensor networks are positioning as the more direct way to obtain these data. The development of solar sensor networks adapted to small-scale systems as microgrids is subject to specific requirements: high updating frequency, high density of measurement points and low investment. This paper proposes a wireless sensor network able to provide snapshots of the irradiance field with an updating frequency of 2 Hz. The network comprised 16 motes regularly distributed over an area of 15 m × 15 m (4 motes × 4 motes, minimum intersensor distance of 5 m). The irradiance values were estimated from illuminance measurements acquired by lux-meters in the network motes. The estimated irradiances were validated with measurements of a secondary standard pyranometer obtaining a mean absolute error of 24.4 W/m 2 and a standard deviation of 36.1 W/m 2 . The network was able to capture the cloud motion and the main features of the irradiance field even with the reduced dimensions of the monitoring area. These results and the low-cost of the measurement devices indicate that this concept of solar sensor networks would be appropriate not only for photovoltaic plants in the range of MW, but also for smaller systems such as the ones installed in microgrids.

scholarly journals Short-term post-mortality scavenging and longer term recovery after anoxia in the northern Adriatic Sea

2013 ◽  
Vol 10 (11) ◽  
pp. 7647-7659 ◽  
Author(s):  
M. Blasnig ◽  
B. Riedel ◽  
L. Schiemer ◽  
M. Zuschin ◽  
M. Stachowitsch
Keyword(s):  
Adriatic Sea ◽  
Time Lapse ◽  
Hermit Crabs ◽  
Small Scale ◽  
Short Term ◽  
Northern Adriatic Sea ◽  
Northern Adriatic ◽  
Hexaplex Trunculus ◽  
Distinct Sequence ◽  
And Function

Abstract. The northern Adriatic Sea is one of nearly 500 areas worldwide suffering widespread mortalities due to anoxia. The present study documents post-anoxia macrofauna dynamics after experimentally inducing small-scale anoxia in 24 m depth (2 plots, each 50 cm × 50 cm). Time-lapse camera deployments examined short-term scavenging of the moribund and dead organisms (multi-species clumps consisting of sponges and ascidians) over two 3-day periods (August 2009: 71.5 h, September 2009: 67.5 h). Longer term recovery (days to 2 yr) in the same two plots was examined with an independent photo series. Scavengers arrived quickly and in a distinct sequence: demersal (Gobius niger, Serranus hepatus) and benthopelagic fishes (Diplodus vulgaris, Pagellus erythrinus), followed by hermit crabs (Paguristes eremita, showing a clear day/night rhythm in presence) and gastropods (Hexaplex trunculus). This sequence is attributed to the relative speeds and densities of the organisms. The sessile fauna was largely removed or consumed within seven (August plot) and 13 (September plot) days after anoxia, confirming our first hypothesis that decaying organisms are quickly utilised. The scavengers remained in dense aggregations (e.g. up to 33 P. eremita individuals at one time) as long as dead organisms were available. No recovery of sessile macroepibenthos macroepibenthos occurred in the experimental plots one and two years after anoxia, undermining our second hypothesis that small denuded areas are more rapidly recolonised. This study underlines the sensitivity of this soft-bottom community and supports calls for reducing additional anthropogenic disturbances such as fishing practices that further impede recolonisation and threaten benthic community structure and function over the long term.

Selective Transport of Water-Soluble Proteins from Aqueous to Ionic Liquid Phase via a Temperature-Sensitive Phase Change of These Mixtures

2012 ◽  
Vol 65 (11) ◽  
pp. 1548 ◽  
Author(s):  
Yuki Kohno ◽  
Nobuhumi Nakamura ◽  
Hiroyuki Ohno
Keyword(s):  
Phase Change ◽  
Aqueous Phase ◽  
Selective Dissolution ◽  
Selective Extraction ◽  
Soluble Proteins ◽  
Water Soluble ◽  
Temperature Sensitive ◽  
Salting Out ◽  
Key Factor ◽  
The Difference

Mixtures of some ionic liquids (ILs) and water show reversible phase change between a homogeneous mixture and phase-separated state by a small change in temperature. Some water-soluble proteins have been migrated from the aqueous to the IL phase. When tetrabutylphosphonium 2,4,6-trimethylbenzenesulfonate was used as an IL, cytochrome c (Cyt.c) was found to be extracted from the water phase to the IL phase. Conversely, both horseradish peroxidase (HRP) and azurin remained in the aqueous phase. This selective extraction was comprehended to be due to the difference in solubility of these proteins in both phases. The separated aqueous phase contained a small amount of IL, which induced the salting-out of Cyt.c. On the other hand, condensed IL phase promoted the salting-in of Cyt.c. As a result, Cyt.c was preferably dissolved in the hydrated IL phase rather than aqueous phase. In the case of HRP, there was only a salting-out profile upon increasing the concentration of IL, which induced selective dissolution of HRP in the aqueous phase. These results clearly suggest that the profile of salting-out and salting-in for proteins is the key factor to facilitate the selective extraction of proteins from aqueous to the IL phase.

scholarly journals The Unbearable Lightness of Trust: Trade, conviviality, and the life-world of Indian export agents in Yiwu, China

2021 ◽  
pp. 1-31
Author(s):  
Filippo Osella
Keyword(s):  
United Arab Emirates ◽  
Small Scale ◽  
Export Trade ◽  
Short Term ◽  
Economic Interests ◽  
Life World ◽  
Extreme Caution ◽  
The World ◽  
Ethnographic Data ◽  
World Centre

Abstract Drawing on ethnographic data collected in China, the United Arab Emirates (UAE), and India, this article explores the life-world and practices of small-scale Indian export agents based in Yiwu, China, the world centre for the export of small commodities. It shows that in a market overdetermined by fast-moving goods, short-term gains, and low margins, export agents have to steer their way between acting with extreme caution or taking risks with their clients and suppliers. These apparently contradictory dispositions or orientations are negotiated by the judicious exercise of mistrust and suspicion. The article suggests not only that mistrust is valued and cultivated as an indispensable practical resource for success in Yiwu's export trade, but that contingent relations of trust between market players emerge at the interstices of a generalized mutual mistrust, via the mobilization of practices of hospitality, commensality, and masculine conviviality. Indeed, feelings of amity and mutuality elicited by the performance of modalities of social intimacy become the affective terrain upon which divergent economic interests might be reconciled and taken forward. That is, mistrust might not lead to generalized distrust, instead a situational or contingent trust might actually emerge through the judicious exercise of mistrust.

scholarly journals Supporting Spatial Management of Data-Poor, Small-Scale Fisheries With a Bayesian Approach

2021 ◽  
Vol 8 ◽  
Author(s):  
Jennifer Rehren ◽  
Maria Grazia Pennino ◽  
Marta Coll ◽  
Narriman Jiddawi ◽  
Christopher Muhando
Keyword(s):  
Spatial Distribution ◽  
Marine Conservation ◽  
Environmental Drivers ◽  
Small Scale ◽  
Target Species ◽  
Short Term ◽  
Conservation Areas ◽  
Bayesian Hierarchical ◽  
Small Scale Fisheries ◽  
Spatial Management

Marine conservation areas are an important tool for the sustainable management of multispecies, small-scale fisheries. Effective spatial management requires a proper understanding of the spatial distribution of target species and the identification of its environmental drivers. Small-scale fisheries, however, often face scarcity and low-quality of data. In these situations, approaches for the prioritization of conservation areas need to deal with scattered, biased, and short-term information and ideally should quantify data- and model-specific uncertainties for a better understanding of the risks related to management interventions. We used a Bayesian hierarchical species distribution modeling approach on annual landing data of the heavily exploited, small-scale, and data-poor fishery of Chwaka Bay (Zanzibar) in the Western Indian Ocean to understand the distribution of the key target species and identify potential areas for conservation. Few commonalities were found in the set of important habitat and environmental drivers among species, but temperature, depth, and seagrass cover affected the spatial distribution of three of the six analyzed species. A comparison of our results with information from ecological studies suggests that our approach predicts the distribution of the analyzed species reasonably well. Furthermore, the two main common areas of high relative abundance identified in our study have been previously suggested by the local fisher as important areas for spatial conservation. By using short-term, catch per unit of effort data in a Bayesian hierarchical framework, we quantify the associated uncertainties while accounting for spatial dependencies. More importantly, the use of accessible and interpretable tools, such as the here created spatial maps, can frame a better understanding of spatio-temporal management for local fishers. Our approach, thus, supports the operability of spatial management in small-scale fisheries suffering from a general lack of long-term fisheries information and fisheries independent data.

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