Historical changes of sedimentary P-binding forms and their ecological driving mechanism in a typical “grass-algae” eutrophic lake

2021 ◽  
Vol 204 ◽  
pp. 117604
Author(s):  
Shuai Ding ◽  
Yan Liu ◽  
Solomon Felix Dan ◽  
Lixin Jiao
Keyword(s):  
Eutrophic Lake ◽  
Driving Mechanism ◽  
Historical Changes ◽  
Binding Forms

Phosphorus-binding forms in the sediment of an oligotrophic and an eutrophic hardwater lake of the Baltic Lake District (Germany)

1998 ◽  
Vol 37 (3) ◽  
pp. 51-58 ◽  
Author(s):  
Thomas Gonsiorczyk ◽  
Peter Casper ◽  
Rainer Koschel
Keyword(s):  
Eutrophic Lake ◽  
Oligotrophic Lake ◽  
Sediment Surface ◽  
Eutrophic Lakes ◽  
P Release ◽  
Binding Forms ◽  
Fe And Mn ◽  
Lake Stechlin ◽  
High Concentrations ◽  
The Baltic

The vertical distribution of various phosphorus (P)-binding forms, associated potential P-binding partners and the composition of dry material were investigated in the bottom sediments of the dimictic oligotrophic Lake Stechlin and the dimictic eutrophic Lake Feldberger Haussee. Reductant soluble P (Fe- and Mn-bound) at the sediment surface (0−1 cm) was considerably higher in the oligotrophic Lake Stechlin (1.29 g kg−1) than in the eutrophic Lake Haussee (0.32 g kg−1). The amounts of dissolved, loosely adsorbed, metal oxide- and calcium carbonate bound P were higher in the eutrophic lake. The depth profiles of the investigated P species indicated that the mobilization of Fe- and Mn-bound P is the most important mechanism of P-release in oligotrophic lakes, whereas the mobilization of recently sedimented labile organic bound P seems to be the driving force of P-release in eutrophic lakes. In both lakes autochthonous calcite precipitations occurs during the summer months. The coprecipitation of P with calcite is an important self-cleaning mechanism in eutrophic hardwater lakes and contributes to the permanent burial of P in the sediments. Although, the precipitation of calcite is inhibited by the presence of high concentrations of soluble reactive P, the coprecipitation of P with calcite seems to be enhanced.

Reconstruction of maximum temperature on Zhegu Mountain, western Sichuan Plateau (China)

2020 ◽  
Vol 81 ◽  
pp. 1-14
Author(s):  
M Keyimu ◽  
Z Li ◽  
Y Zhao ◽  
Y Dong ◽  
B Fu ◽  
...  
Keyword(s):  
Tree Growth ◽  
Ring Width ◽  
Volcanic Eruptions ◽  
Southwestern China ◽  
Maximum Temperature ◽  
Driving Mechanism ◽  
Western Sichuan ◽  
Relationship Analysis ◽  
Decadal Scale ◽  
Thermal Variability

Historical temperature reconstructions at high altitudes are still insufficient in southwestern China, which is considered one of the most sensitive areas to climate change in the world. Here we developed a tree ring-width chronology of Faxon fir Abies fargesii var. faxoniana at the upper timber line on Zhegu Mountain, Miyaluo Scenic Area, western Sichuan, China. The climate-tree growth relationship analysis indicated temperature as the dominant regulator on radial tree growth in this region. The reconstruction of aggregated maximum temperature (TMX) of autumn and winter for the period 1856-2016 was achieved with a linear regression model that accounted for 43.6% of the actual variability in the common time series (1954-2016). The reconstruction identified 4 warm periods and 3 cold periods. Similarities of warm and cold periods with previously published reconstructions from nearby sites indicated the reliability of our reconstruction. The significant positive correlation between TMX reconstruction and the Asian-Pacific Oscillation index and the Atlantic Multi-decadal Oscillation index suggested a linkage between large-scale climate circulations and the thermal variability at a multi-decadal scale on the western Sichuan Plateau. We also found that solar activity exerted a strong influence on decadal temperature variability in this region. The cold periods were matched well with historical large volcanic eruptions. Our results strengthen the historical climatic information in southwestern China and contribute to further understanding the regional thermal variability as well as its driving mechanism.

Family Secrets and their Destructive Consequences: In My Father’s Den (Brad McGann, 2004)

2018 ◽  
Author(s):  
Alistair Fox
Keyword(s):  
New Zealand ◽  
Coming Of Age ◽  
Family Members ◽  
Historical Changes ◽  
Family Secrets ◽  
Effects On Children

This chapter analyses Brad McGann’s highly esteemed adaptation (2004) of Maurice Gee’s novel In My Father’s Den (1972) as evidence of a prevailing trend in New Zealand coming-of-age films whereby the vision of a source work is regularly updated to reflect the different values and perspectives of a later generation. In this case, the updating involves a shift of emphasis from the destructive effects on children of puritan religiosity and repressiveness to those of lack of communication among family members, combined with the preservation of unspoken, but collectively known, family secrets, reflecting historical changes that had occurred in New Zealand society since the generation of Gee (born 1931) and that of McGann (born 1964).

Modelling a Multi-Dimensional Model of Memory Performance in Obsessive-Compulsive Disorder: A Multi-Level Meta-Analytic Review.

2020 ◽  
Author(s):  
Sofia Persson ◽  
Alan Yates ◽  
Klaus Kessler ◽  
Ben Harkin
Keyword(s):  
Executive Function ◽  
Obsessive Compulsive Disorder ◽  
Memory Load ◽  
Memory Performance ◽  
Effect Sizes ◽  
Driving Mechanism ◽  
Obsessive Compulsive ◽  
Compulsive Disorder ◽  
Analytic Review ◽  
Multi Level

Even though memory performance is a commonly researched aspect of Obsessive-Compulsive Disorder (OCD), a coherent and unified explanation of the role of specific cognitive factors has remained elusive. To address this, the present meta-analysis examined the predictive validity of Harkin and Kessler’s (2011) Executive Function (E), Binding Complexity (B) and Memory Load (L) Classification System with regards to affected vs. unaffected memory performance in OCD. We employed a multi-level meta-analytic approach (Viechtbauer, 2010) to accommodate the interdependent nature of the EBL model and interdependency of effect sizes (305 effect sizes from 144 studies, including 4424 OCD patients). Results revealed that the EBL model predicted memory performance, i.e., as EBL demand increases, those with OCD performed progressively worse on memory tasks. Executive function was the driving mechanism behind the EBL’s impact on OCD memory performance and negated effect size differences between visual and verbal tasks in those with OCD. Comparisons of sub-task effect sizes were also generally in accord with the cognitive parameters of the EBL taxonomy. We conclude that standardised coding of tasks along individual cognitive dimensions and multi-level meta-analyses provides a new approach to examine multi-dimensional models of memory and cognitive performance in OCD and other disorders.

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