scholarly journals Hydropower‐driven thermal changes, biological responses and mitigating measures in northern river systems

Author(s):  
Jan Heggenes ◽  
Morten Stickler ◽  
Knut Alfredsen ◽  
John E. Brittain ◽  
Ana Adeva‐Bustos ◽  
...  
2021 ◽  
Vol 10 (2) ◽  
pp. 132-132
Author(s):  
Raju Vyas ◽  
Harshil Patel

The crowned river turtle, Hardella thurjii (Gray, 1831) is widely distributed from Pakistan to Bangladesh, and possibly in western Myanmar. It prefers the middle and lower reaches of the northern river systems on the Indian subcontinent, comprising the Indus, Ganga, Brahmaputra, and their tributaries. The species is classified as Endangered, but nationally remains a poorly protected species under the Indian Wildlife Protection Act. This communication presents the first photographic evidence of the crowned river turtle, from Gujarat State, India. It was previously reported from North Gujarat two decades ago, but without any evidence.


2010 ◽  
Author(s):  
Charlotte Leonie Stewart ◽  
Jolanta Opacka-Juffry ◽  
Changiz Mohiyeddini

2020 ◽  
Vol 123 (4) ◽  
pp. 655-668
Author(s):  
N. Lenhardt ◽  
W. Altermann ◽  
F. Humbert ◽  
M. de Kock

Abstract The Palaeoproterozoic Hekpoort Formation of the Pretoria Group is a lava-dominated unit that has a basin-wide extent throughout the Transvaal sub-basin of South Africa. Additional correlative units may be present in the Kanye sub-basin of Botswana. The key characteristic of the formation is its general geochemical uniformity. Volcaniclastic and other sedimentary rocks are relatively rare throughout the succession but may be dominant in some locations. Hekpoort Formation outcrops are sporadic throughout the basin and mostly occur in the form of gentle hills and valleys, mainly encircling Archaean domes and the Palaeoproterozoic Bushveld Complex (BC). The unit is exposed in the western Pretoria Group basin, sitting unconformably either on the Timeball Hill Formation or Boshoek Formation, which is lenticular there, and on top of the Boshoek Formation in the east of the basin. The unit is unconformably overlain by the Dwaalheuwel Formation. The type-locality for the Hekpoort Formation is the Hekpoort farm (504 IQ Hekpoort), ca. 60 km to the west-southwest of Pretoria. However, no stratotype has ever been proposed. A lectostratotype, i.e., the Mooikloof area in Pretoria East, that can be enhanced by two reference stratotypes are proposed herein. The Hekpoort Formation was deposited in a cratonic subaerial setting, forming a large igneous province (LIP) in which short-termed localised ponds and small braided river systems existed. It therefore forms one of the major Palaeoproterozoic magmatic events on the Kaapvaal Craton.


2018 ◽  
Vol 35 (5) ◽  
pp. 536
Author(s):  
Jiayun LU ◽  
Jianbo SONG ◽  
Xiaoyan WANG ◽  
Xiaowei MO ◽  
Suikang WANG ◽  
...  

2001 ◽  
Vol 36 (2) ◽  
pp. 319-330 ◽  
Author(s):  
Mark Servos ◽  
Don Bennie ◽  
Kent Burnison ◽  
Philippa Cureton ◽  
Nicol Davidson ◽  
...  

Abstract A number of biological responses and multigenerational effects, mediated through the disruption of endocrine systems, have been observed in biota exposed to relatively low concentrations of environmental contaminants. These types of responses need to be considered within a weight of evidence approach in our risk assessment and risk management frameworks. However, including endocrine responses in an environmental risk assessment introduces a number of uncertainties that must be considered. A risk assessment of nonylphenol and nonylphenol polyethoxylates (NP/NPE) is used as a case study to demonstrate the sources and magnitude of some of the uncertainties associated with using endocrine disruption as an assessment endpoint. Even with this relatively well studied group of substances, there are substantial knowledge gaps which contribute to the overall uncertainties, limiting the interpretation within the risk assessment. The uncertainty of extrapolating from in vitro or biochemical responses to higher levels of organization or across species is not well understood. The endocrine system is very complex and chemicals can interact or interfere with the normal function of endocrine systems in a number of ways (e.g., receptors, hormones) which may or may not result in an adverse responses in the whole organism. Using endocrine responses can lead to different conclusions than traditional endpoints due to a variety of factors, such as differences in relative potencies of chemicals for specific endpoints (e.g., receptor binding versus chronic toxicity). The uncertainties can also be considerably larger and the desirability of using endocrine endpoints should be carefully evaluated. Endocrine disruption is a mode of action and not a functional endpoint and this needs to be considered carefully in the problem formulation stage and the interpretation of the weight of evidence.


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