Patterns of invertebrate emergence and succession in flooded wetland mesocosms

2020 ◽  
Vol 71 (10) ◽  
pp. 1373
Author(s):  
I. Growns ◽  
S. Lewis ◽  
D. Ryder ◽  
W. Tsoi ◽  
B. Vincent

Floodplain wetlands are some of the most productive ecosystems available to aquatic and terrestrial organisms. However, regulation of lowland rivers can disrupt ecological processes occurring in the river–floodplain ecosystems, and environmental water can be delivered to affected wetlands to maintain productivity. It is not well understood at what stage following inundation there would be sufficient invertebrate biomass and large-sized individuals to support production and reproduction of secondary consumers. In this study we follow changes in the abundances of invertebrates after wetting in three mesocosm trials using soil from two wetlands from the north of the Murray–Darling Basin over 6-week periods. Peak abundances generally occurred in either the fifth or sixth weeks, but abundances were high after 2–3 weeks. Our results suggest that inundation of wetlands using environmental watering can achieve high productivity within a short time frame, within weeks. However, how quickly the high productivity is passed on to second-order consumers remains unclear and should be an area of future research.

2021 ◽  
Author(s):  
Wing (Iris) Tsoi ◽  
Ivor Growns ◽  
Mark Southwell ◽  
Darren Ryder ◽  
Paul Frazier

Abstract Floodplain wetlands play a significant role in the storage of sediment and water and support high levels of nutrient cycling that lead to substantial primary production and high biodiversity. This storage, cycling and production system is driven by intermittent inundation. In regulated rivers the link between channel flows and floodplain inundation is often impacted with reduction in the frequency and duration of inundation. Managed floodplain inundation is us being used as a tool to help restore floodplain wetland processes and rehabilitate river systems. However, the use of managed water for the environment remains contentious and it is important to quantify the outcomes of re-introducing water to floodplain wetland systems. We examined the effects of environmental floodplain watering on water chemistry and three groups of invertebrates, including benthic and pelagic invertebrates and macroinvertebrates, in wetlands on the Gwydir River system in the north of the Murray-Darling Basin. We hypothesised that wetlands that were inundated for longer periods of time would have altered water chemistry and support a greater richness and abundance of invertebrates, thus altering their assemblage structures. Water chemistry and the assemblage structure of all three invertebrate groups in the wetlands was significantly influenced by the time since connection (TSC) to their respective rivers and therefore inundation period. The microinvertebrate abundance of was positively associated with TSC, but not macroinvertebrates. This suggests that the duration of connection between the channel and floodplain is important in maintaining the ecology and food webs in the wetlands.


2012 ◽  
Vol 63 (7) ◽  
pp. 576 ◽  
Author(s):  
A. J. King ◽  
Z. Tonkin ◽  
J. Lieshcke

Blackwater contains high levels of dissolved organic carbon that can be rapidly consumed by microbes, sometimes leading to extremely low levels of dissolved oxygen (hypoxia) and drastic consequences for aquatic life, including fish kills. Drought-breaking rains in late 2010 inundated large areas of the Barmah–Millewa Forest, southern Murray–Darling Basin, Australia, and resulted in a prolonged hypoxic blackwater event within the forest and the Murray River downstream. This study investigated the short-term effects of the blackwater event on fish and crayfish. Compared with non-affected sites, blackwater affected sites had: significantly higher abundances of emerged Murray crayfish (Euastacus armatus) that were vulnerable to desiccation, predation and exploitation; large numbers of dead or dying shrimp and yabbies; significantly reduced abundances of native fish; but contained similar abundances of alien fish species (particularly common carp, Cyprinus carpio). The nature of the mechanisms that caused these changes and the longer term significance of the event on the river system remains an important area for future research. We also propose a range of management considerations for reducing the blackwater impacts, such as the timing of environmental water delivery after prolonged drought and the importance of maintaining river–floodplain connectivity during flood periods.


Kavkaz-forum ◽  
2021 ◽  
Author(s):  
Е.В. ФЕДОСОВА

В рамках данной статьи рассматриваются проблемы возрождения казачества на Северном Кавказе и Юге России. Современное казачество – это один из основных факторов, влияющих на социально-политическую ситуацию Северного Кавказа и Юга России. Однако формирование и возрождение казачества в постсоветский период носит достаточно амбивалентный характер, который в разных социально-политических и экономических обстоятельствах способен формировать противоположные тенденции как самих казачьих движений, так и самым серьезным образом влиять на различные процессы, протекающие в регионе. К сожалению, в силу объективных и иных обстоятельств, проблемы возрождения современного казачества не стали предметом серьезных исследований в рамках научного дискурса. При всем видимом многообразии различных публикаций на тему казачества, к сожалению, отсутствуют единые научные методологические подходы к изучению данного явления общественной жизни. Несмотря на то, что процессы «возрождения казачества» охватили значительное количество людей, особенно в начальный период своего развития, однако в научном дискурсе данный феномен так и не стал предметом междисциплинарного анализа и дискурса. «Казачья тема» фактически сразу была застолблена публицистами или псевдонаучными исследованиями, авторы которых или весьма слабо, или весьма ангажировано ориентировались в истории и специфике «возрождения казачества». В предлагаемом исследовании мы постарались отойти от упрощенства, свойственного псевдоисследованиям казачьей тематики, в основе которых зачастую лежит дескриптивный (описательный) подход к оценке как «возрождения», так и специфики современного казачества. Для наиболее плодотворного анализа перспектив и рисков развития современного казачьего движения был использован проблемно-хронологический подход, который позволил проанализировать развитие казачества в достаточно сжатых временных рамках. Within the framework of this article, the problems of the revival of the Cossacks in the North Caucasus and the South of Russia are considered. The modern Cossacks are one of the main factors influencing the socio-political situation in the North Caucasus and South of Russia. However, the formation and revival of the Cossacks in the post-Soviet period is rather ambivalent in nature, which in different socio-political and economic circumstances is able to form opposite tendencies, both of the Cossack movements themselves, and in the most serious way to influence various processes taking place in the region. Unfortunately, due to objective and other circumstances, the problems of the revival of the modern Cossacks have not become the subject of serious research within the framework of scientific discourse. With all the visible variety of various publications on the topic of the Cossacks, unfortunately, there are no uniform scientific methodological approaches to the study of this phenomenon of public life. Despite the fact that the processes of the "revival of the Cossacks" covered a significant number of people, especially in the initial period of their development, however, in the scientific discourse, this phenomenon has not become the subject of interdisciplinary analysis and discourse. The "Cossack theme" was practically immediately privatized by publicists or pseudoscientific studies, the authors of which were either very weak or very biased in the history and specifics of the "revival of the Cossacks." In the proposed study, we tried to move away from the simplification inherent in pseudo-studies of Cossack topics, which are often based on a descriptive approach to assessing both the “revival” and the specifics of the modern Cossacks. For the most fruitful analysis of the prospects and risks of the development of the modern Cossack movement, a problem-chronological approach was used, which made it possible to analyze the development of the Cossacks in a fairly short time frame.


2020 ◽  
Vol 5 (1) ◽  
pp. 12
Author(s):  
Siti Aisyah Munirah Bohang ◽  
Zainul Ibrahim Zainuddin ◽  
Norhanna Suhoimi

Interaction of CT’s x-ray beams with patient resulted in attenuation process and there are various factors affecting CT attenuation values. The aim of this review is to examine the existed literatures regarding the concept of attenuation in CT and its relationship with body dimension, gender and age in Malay population. Guided by primary question, literature searches were conducted using the established online database; SCOPUS and PubMed. The time frame for literatures was from 2000 to 2019 and only literatures in English language were selected. The size of body dimension has affected the CT attenuation value but it also depending on the type of tissue presence within the region of interest (ROI) such as muscle and fat tissues. Due to larger body framework and higher amount of skeletal muscle mass theoretically males would have higher CT attenuation value than female. CT attenuation value reduces with aging process. Asians including Malay population have smaller body dimension than Caucasians and the mean attenuation value of abdominal region in Asians could differ from 20 HU. Thus, there is a need for future research to investigate the interrelatedness of attenuation in CT (HU) and body dimension within Malay population and close this gap of knowledge. 


SAGE Open ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 215824402199065
Author(s):  
Matthew Canham ◽  
Clay Posey ◽  
Delainey Strickland ◽  
Michael Constantino

Organizational cybersecurity efforts depend largely on the employees who reside within organizational walls. These individuals are central to the effectiveness of organizational actions to protect sensitive assets, and research has shown that they can be detrimental (e.g., sabotage and computer abuse) as well as beneficial (e.g., protective motivated behaviors) to their organizations. One major context where employees affect their organizations is phishing via email systems, which is a common attack vector used by external actors to penetrate organizational networks, steal employee credentials, and create other forms of harm. In analyzing the behavior of more than 6,000 employees at a large university in the Southeast United States during 20 mock phishing campaigns over a 19-month period, this research effort makes several contributions. First, employees’ negative behaviors like clicking links and then entering data are evaluated alongside the positive behaviors of reporting the suspected phishing attempts to the proper organizational representatives. The analysis displays evidence of both repeat clicker and repeat reporter phenomena and their frequency and Pareto distributions across the study time frame. Second, we find that employees can be categorized according to one of the four unique clusters with respect to their behavioral responses to phishing attacks—“Gaffes,” “Beacons,” “Spectators,” and “Gushers.” While each of the clusters exhibits some level of phishing failures and reports, significant variation exists among the employee classifications. Our findings are helpful in driving a new and more holistic stream of research in the realm of all forms of employee responses to phishing attacks, and we provide avenues for such future research.


2021 ◽  
pp. 147737082110006
Author(s):  
Wim Hardyns ◽  
Thom Snaphaan ◽  
Sara Willems ◽  
Lieven J. R. Pauwels

This study examines the ecological reliability, convergent validity and ecological stability of neighbourhood (dis)organizational processes measured by means of two methods: inhabitant surveys and the so-called key informant analysis technique. Considering that ecological processes play a major role in many contemporary criminological theories and research, it is vital to take into account methodological challenges and to question the reliability, validity and stability of the measures reflecting these underlying processes. (Dis)organizational processes are predominantly measured by means of questionnaires surveying neighbourhood inhabitants. To yield ecologically reliable and valid measures this approach requires large numbers of respondents. In this study we analyse the relationships between ecological measures of neighbourhood processes based on surveys of inhabitants versus key informants. The findings suggest that key informants can provide reliable, valid and stable measures of (dis)organizational neighbourhood processes. Therefore, the key informant analysis technique is an essential complementary, or even substitutive, method in the measurement of neighbourhood processes; shared survey-method variance is eliminated and it is possible to survey fewer key informants than inhabitants to obtain reliable and valid information on social trust and disorder. Nevertheless, this method is not suitable for measuring all neighbourhood processes, such as informal social control. Therefore, outstanding challenges and avenues for future research are discussed as well.


Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3872
Author(s):  
Klytaimnistra Katsara ◽  
George Kenanakis ◽  
Zacharias Viskadourakis ◽  
Vassilis M. Papadakis

For multiple years, food packaging migration has been a major concern in food and health sciences. Plastics, such as polyethylene, are continuously utilized in food packaging for preservation and easy handling purposes during transportation and storage. In this work, three types of cheese, Edam, Kefalotyri and Parmesan, of different hardness were studied under two complementary vibrational spectroscopy methods, ATR-FTIR and Raman spectroscopy, to determine the migration of low-density polyethylene from plastic packaging to the surface of cheese samples. The experimental duration of this study was set to 28 days due to the degradation time of the selected cheese samples, which is clearly visible after 1 month in refrigerated conditions at 4 °C. Raman and ATR-FTIR measurements were performed at a 4–3–4–3 day pattern to obtain comparative results. Initially, consistency/repeatability measurement tests were performed on Day0 for each sample of all cheese specimens to understand if there is any overlap between the characteristic Raman and ATR-FTIR peaks of the cheese with the ones from the low-density polyethylene package. We provide evidence that on Day14, peaks of low-density polyethylene appeared due to polymeric migration in all three cheese types we tested. In all cheese samples, microbial outgrowth started to develop after Day21, as observed visually and under the bright-field microscope, causing peak reverse. Food packaging migration was validated using two different approaches of vibrational spectroscopy (Raman and FT-IR), revealing that cheese needs to be consumed within a short time frame in refrigerated conditions at 4 °C.


2021 ◽  
pp. 089826432110150
Author(s):  
Janet M. Boekhout ◽  
Esmee Volders ◽  
Catherine A. W. Bolman ◽  
Renate H. M. de Groot ◽  
Lilian Lechner

Objectives: This study explores the effects of the Active Plus intervention aiming to decrease loneliness among older adults (>65 years) with chronic diseases. Methods: A randomized controlled trial (RCT) was performed (N = 585; age: M = 74.5 years, SD = 6.4), assessing loneliness at baseline, 6 months and 12 months. Outcome measures in the multilevel linear regression analyses were total, social and emotional loneliness. Results: At 12 months, significant decreases in total ( B = −.37, p = .01) and social loneliness ( B = −.24, p = .02) were found. Age was a significant moderator for total and social loneliness; however, the intervention was effective only for participants aged 80 years and older. Discussion: The Active Plus intervention showed a significant decrease in total and social loneliness and was especially beneficial for the vulnerable age group of 80 years and older. A more comprehensive tool for measuring social activity and mobility impairments, and using a longer time frame to detect loneliness changes, may form interesting future research.


Agronomy ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 673 ◽  
Author(s):  
John Clifton-Brown ◽  
Kai-Uwe Schwarz ◽  
Danny Awty-Carroll ◽  
Antonella Iurato ◽  
Heike Meyer ◽  
...  

Miscanthus, a C4 perennial grass native to Eastern Asia, is being bred to provide biomass for bioenergy and biorenewable products. Commercial expansion with the clonal hybrid M. × giganteus is limited by low multiplication rates, high establishment costs and drought sensitivity. These limitations can be overcome by breeding more resilient Miscanthus hybrids propagated by seed. Naturally occurring fast growing indigenous Miscanthus species are found in diverse environments across Eastern Asia. The natural diversity provides for plant breeders, the genetic resources to improve yield, quality, and resilience for a wide range of climates and adverse abiotic stresses. The challenge for Miscanthus breeding is to harness the diversity through selections of outstanding wild types, parents, and progenies over a short time frame to deploy hybrids that make a significant contribution to a world less dependent on fossil resources. Here are described the strategies taken by the Miscanthus breeding programme at Aberystwyth, UK and its partners. The programme built up one of the largest Miscanthus germplasm collections outside Asia. We describe the initial strategies to exploit the available genetic diversity to develop varieties. We illustrate the success of combining diverse Miscanthus germplasm and the selection criteria applied across different environments to identify promising hybrids and to develop these into commercial varieties. We discuss the potential for molecular selections to streamline the breeding process.


The Holocene ◽  
2019 ◽  
Vol 30 (3) ◽  
pp. 479-484
Author(s):  
Daniel P Maxbauer ◽  
Mark D Shapley ◽  
Christoph E Geiss ◽  
Emi Ito

We present two hypotheses regarding the evolution of Holocene climate in the Northern Rocky Mountains that stem from a previously unpublished environmental magnetic record from Jones Lake, Montana. First, we link two distinct intervals of fining magnetic grain size (documented by an increasing ratio of anhysteretic to isothermal remanent magnetization) to the authigenic production of magnetic minerals in Jones Lake bottom waters. We propose that authigenesis in Jones Lake is limited by rates of groundwater recharge and ultimately regional hydroclimate. Second, at ~8.3 ka, magnetic grain size increases sharply, accompanied by a drop in concentration of magnetic minerals, suggesting a rapid termination of magnetic mineral authigenesis that is coeval with widespread effects of the 8.2 ka event in the North Atlantic. This association suggests a hydroclimatic response to the 8.2 ka event in the Northern Rockies that to our knowledge is not well documented. These preliminary hypotheses present compelling new ideas that we hope will both highlight the sensitivity of magnetic properties to record climate variability and attract more work by future research into aridity, hydrochemical response, and climate dynamics in the Northern Rockies.


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