‘Looping caves’ versus ‘water table caves’: The role of base-level changes and recharge variations in cave development

Geomorphology ◽  
2014 ◽  
Vol 204 ◽  
pp. 683-691 ◽  
Author(s):  
Franci Gabrovšek ◽  
Philipp Häuselmann ◽  
Philippe Audra
Keyword(s):  
Water Table ◽  
Base Level

Societal discontent will increase in Bahrain

2021 ◽  
Keyword(s):  
Large Scale ◽  
Political Representation ◽  
Social Protest ◽  
Small Scale ◽  
Content Type ◽  
High Profile ◽  
Arab Uprisings ◽  
Base Level

Significance Although large-scale social protest in Bahrain has been cowed over the ten years since the ‘Arab uprisings’, small-scale demonstrations recur, reflecting a base level of discontent. Mobilising issues include economic pressures, limited political representation (especially of the Shia majority) and, most recently, ties with Israel. Impacts Despite protests, Israel’s and Bahrain’s respective ambassadors will keep up high-profile activity and statements. The authorities are likely to exaggerate the role of Iranian interference in order to deepen the Sunni-Shia divide. If Riyadh manages to extricate itself from the Yemen war, that could partly reduce the pressure on Manama.

scholarly journals Under the surface: what we know about the threats to subterranean fishes in Brazil

2021 ◽  
Vol 19 (3) ◽  
Author(s):  
Maria Elina Bichuette ◽  
Jonas Eduardo Gallão
Keyword(s):  
Water Table ◽  
Food Restriction ◽  
Hyporheic Zone ◽  
Public Awareness ◽  
River Basins ◽  
Physical Change ◽  
Alluvial Sediments ◽  
Base Level ◽  
Threatened Fauna ◽  
Brazilian Biodiversity

Abstract The present work brings information on threats to the subterranean fishes in Brazil. Currently, at least 36 species are known, 22 of which are already formally described. Endemism is the rule for most of them. Regarding their conservation, these fishes are in general considered threatened: and most of the already formally described species are included in national lists of threatened fauna, and only four of them are included in the global list of the IUCN. Regarding habitats, Brazilian subterranean fishes occur in alluvial sediments (part of the hyporheic zone), shallow base-level streams, flooded caves, lakes in the water table, upper vadose tributaries, and epikarst aquifers. We detected 11 main threats, mainly related to agriculture, pasture, and hydroelectric plans, but unmanaged tourism and pollution are also significant threats. Two threats affect a high number of species (physical change of the habitat and food restriction). The river basins with the higher number of identified threats are the upper Tocantins (eight) followed by the upper Paraguaçu (six). Effective proposals to protect this neglected component of the Brazilian biodiversity are still scarce, such as monitoring projects and their function in the subterranean communities, besides education projects aiming to develop public awareness.

scholarly journals Consequences of Increased Variation in Peatland Hydrology for Carbon Storage: Legacy Effects of Drought and Flood in a Boreal Fen Ecosystem

2021 ◽  
Vol 8 ◽  
Author(s):  
Evan S. Kane ◽  
Catherine M. Dieleman ◽  
Danielle Rupp ◽  
Kevin H. Wyatt ◽  
Allison R. Rober ◽  
...  
Keyword(s):  
Water Table ◽  
Algal Biomass ◽  
Gross Primary Production ◽  
Temporal Trends ◽  
Sink Strength ◽  
Legacy Effects ◽  
Algal Production ◽  
Rich Fen ◽  
C Cycling

Globally important carbon (C) stores in boreal peatlands are vulnerable to altered hydrology through changes in precipitation and runoff patterns, groundwater inputs, and a changing cryosphere. These changes can affect the extent of boreal wetlands and their ability to sequester and transform C and other nutrients. Variation in precipitation patterns has also been increasing, with greater occurrences of both flooding and drought periods. Recent work has pointed to the increasing role of algal production in regulating C cycling during flooded periods in fen peatlands, but exactly how this affects the C sink-strength of these ecosystems is poorly understood. We evaluated temporal trends in algal biomass, ecosystem C uptake and respiration (using static and floating chamber techniques), and spectroscopic indicators of DOM quality (absorbance and fluorescence) in a boreal rich-fen peatland in which water table position had been experimentally manipulated for 13 years. Superimposed on the water table treatments were natural variations in hydrology, including periods of flooding, which allowed us to examine the legacy effects of flooding on C cycling dynamics. We had a particular focus on understanding the role of algae in regulating C cycling, as the relative contribution of algal production was observed to significantly increase with flooding. Ecosystem measures of gross primary production (GPP) increased with algal biomass, with higher algal biomass and GPP measured in the lowered water table treatment two years after persistent flooding. Prior to flooding the lowered treatment was the weakest C sink (as CO2), but this treatment became the strongest sink after flooding. The lower degree of humification (lower humification index, HIX) and yet lower bioavailability (higher spectral slope ratio, Sr) of DOM observed in the raised treatment prior to flooding persisted after two years of flooding. An index of free or bound proteins (tyrosine index, TI) increased with algal biomass across all plots during flooding, and was lowest in the raised treatment. As such, antecedent drainage conditions determined the sink-strength of this rich fen—which was also reflected in DOM characteristics. These findings indicate that monitoring flooding history and its effects on algal production could become important to estimates of C balance in northern wetlands.

scholarly journals Drainage and erosion of Cambodia’s great lake in the middle-late Holocene: The combined role of climatic drying, base-level fall and river capture

2020 ◽  
Vol 236 ◽  
pp. 106265 ◽  
Author(s):  
Stephen E. Darby ◽  
Peter G. Langdon ◽  
James L. Best ◽  
Julian Leyland ◽  
Christopher R. Hackney ◽  
...  
Keyword(s):  
Great Lake ◽  
Late Holocene ◽  
Base Level ◽  
River Capture

Water table variations in the hyperarid Atacama Desert: Role of the increasing groundwater extraction in the pampa del tamarugal (Northern Chile)

2019 ◽  
Vol 168 ◽  
pp. 9-16 ◽  
Author(s):  
Benoît Viguier ◽  
Hervé Jourde ◽  
Véronique Leonardi ◽  
Linda Daniele ◽  
Christelle Batiot-Guilhe ◽  
...  
Keyword(s):  
Water Table ◽  
Atacama Desert ◽  
Northern Chile ◽  
Groundwater Extraction ◽  
Pampa Del Tamarugal

Dynamics of Soil Surface Bulk Density: Role of Water Table Elevation and Rainfall Duration

2008 ◽  
Vol 72 (2) ◽  
pp. 412-423 ◽  
Author(s):  
B. Augeard ◽  
L. M. Bresson ◽  
S. Assouline ◽  
C. Kao ◽  
M. Vauclin
Keyword(s):  
Bulk Density ◽  
Water Table ◽  
Soil Surface ◽  
Rainfall Duration

scholarly journals Decentralization of society as national trend

2018 ◽  
pp. 89-97
Author(s):  
Lidiia Horoshkova ◽  
Vladimir Volkov ◽  
Roman Karbivnychyi
Keyword(s):  
Comparative Analysis ◽  
Public Authority ◽  
Self Management ◽  
Wide Scope ◽  
Public Corporations ◽  
Base Level ◽  
Negative Results ◽  
Executive Authority ◽  
Positive Results

In work the analysis of experience realization reforming administratively-territorial device and decentralization of management in the European countries is carried out. The comparisons of different models of decentralization of authority are carried out. The features of administrative-territorial transformations in the countries - members of EU are investigated which have resulted in positive and negative results. Is shown, that the European practice demonstrates a growing role of local self-management in system of public authority and opportunity of effective delimitation of powers of bodies of the executive authority and local self-management in nation-wide and territorial management. Is established, that in the majority of the countries of Europe at local and regional levels practically all to the competence, except for competent of nation-wide meaning(importance), belong to powers of bodies of local self-management. Is established, that in the countries of Europe the tendency to integration of administrative - territorial units of a base level is traced which answers a level of communities in Ukraine and also decentralization and reforming of functional powers in system administratively - territorial device. The carried out comparative analysis of powers of administrative-territorial units in the different countries, structure and features of formation of the incomes of local bodies self-management. On the basis of the carried out(spent) analysis the carried out offers concerning formation of the Ukrainian model of decentralization. Is proved, that for reception of positive results of decentralization of authority in Ukraine it is necessary simultaneously to take into account such aspects: introduction of mechanisms of wide attraction of the members of territorial communities to participation in management; to develop communities as public corporations on own resources; to ensure wide scope of local self-management, to expand their jurisdiction on territory outside the occupied items; the decentralization of powers can be accompanied by decentralization of budget resources.

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