Can dung beetles (Scarabaeinae) indicate the status of Amazonia’s ecosystems? Insights integrating anthropogenic disturbance with seasonal patterns

2017 ◽  
Vol 67 (3-4) ◽  
pp. 301-318 ◽  
Author(s):  
Reinaldo L. Cajaiba ◽  
Eduardo Périco ◽  
Wully B. da Silva ◽  
Mário Santos

Temporal and spatial variation in dung beetles abundances is a pattern observed in many tropical forests. The present study evaluated the seasonal patterns of dung beetles in a range of increasingly disturbed ecosystems of the state of Pará, northern Brazil, to identify valuable disturbance indicators. The areas included native forest, agriculture, pasture for extensive livestock grazing and secondary forests. Fieldwork was carried out encompassing the complete range of environmental conditions encountered during the year. In total, 13,649 individuals were captured within 23 genera and 99 species but with pronounced differences among ecosystems and seasons. The obtained results seem to demonstrate that dung beetles can be used to help identify ecosystems under very complex and variable environmental conditions. The ecological drift observed also demonstrates the possibility of using dung beetles as ecological indicators of disturbance in Amazonia.

Oryx ◽  
2019 ◽  
Vol 53 (3) ◽  
pp. 415-423 ◽  
Author(s):  
Brett Wilson ◽  
Morena Mills ◽  
Maksim Kulikov ◽  
Colin Clubbe

AbstractForest ecosystems are rich in biodiversity and provide valuable ecosystem services, but are declining worldwide. Malus niedzwetzkyana, an Endangered wild relative of domesticated apples, is an important component of the walnut–fruit forests of Central Asia. Its iconic pink blossom and genetic properties give it special cultural and scientific significance, but livestock grazing and firewood collection threaten its survival. The conservation of the species and its native forest ecosystem is critical and urgent. This study provides information on the ecology and population of M. niedzwetzkyana and the threats affecting its habitat, improving our understanding of its distribution and proposing measures to reduce threats. We collected ecological data and assessed population structure and threats at four forest sites in southern Kyrgyzstan. We mapped 149 individuals, creating the largest known dataset for this species. We developed species distribution models for M. niedzwetzkyana to identify climatically suitable regions and potential areas for restoration. Sary-Chelek Biosphere Reserve contained the largest expanse of pristine forest and the most stable M. niedzwetzkyana population, followed by Kara-Alma Forestry Unit. Forests in the Gava Forestry Unit and Dashman Reserve were most extensively damaged by humans and livestock. The wild apple's favoured habitat was south-west facing slopes with a gradient < 30° and a relatively open canopy. Overall, the study population was vulnerable to extinction with limited regeneration potential. We recommend short-term population enhancement through planting projects and increased protection of individuals in pristine sites. Community-based conservation initiatives should be prioritized in extensively damaged sites, and larger-scale reforestation of these forests needs to be considered.


Author(s):  
Frank J. Longo

Measurement of the egg's electrical activity, the fertilization potential or the activation current (in voltage clamped eggs), provides a means of detecting the earliest perceivable response of the egg to the fertilizing sperm. By using the electrical physiological record as a “real time” indicator of the instant of electrical continuity between the gametes, eggs can be inseminated with sperm at lower, more physiological densities, thereby assuring that only one sperm interacts with the egg. Integrating techniques of intracellular electrophysiological recording, video-imaging, and electron microscopy, we are able to identify the fertilizing sperm precisely and correlate the status of gamete organelles with the first indication (fertilization potential/activation current) of the egg's response to the attached sperm. Hence, this integrated system provides improved temporal and spatial resolution of morphological changes at the site of gamete interaction, under a variety of experimental conditions. Using these integrated techniques, we have investigated when sperm-egg plasma membrane fusion occurs in sea urchins with respect to the onset of the egg's change in electrical activity.


Author(s):  
Didier Debaise

Which kind of relation exists between a stone, a cloud, a dog, and a human? Is nature made of distinct domains and layers or does it form a vast unity from which all beings emerge? Refusing at once a reductionist, physicalist approach as well as a vitalistic one, Whitehead affirms that « everything is a society » This chapter consequently questions the status of different domains which together compose nature by employing the concept of society. The first part traces the history of this notion notably with reference to the two thinkers fundamental to Whitehead: Leibniz and Locke; the second part defines the temporal and spatial relations of societies; and the third explores the differences between physical, biological, and psychical forms of existence as well as their respective ways of relating to environments. The chapter thus tackles the status of nature and its domains.


Forests ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 25
Author(s):  
László Somay ◽  
Viktor Szigeti ◽  
Gergely Boros ◽  
Réka Ádám ◽  
András Báldi

Wood pastures are home to a variety of species, including the dung beetle. Dung beetles are an important functional group in decomposition. Specifically, in terms of livestock manure, they not only contribute to nutrient cycling but are key players in supporting human and animal health. Dung beetles, however, are declining in population, and urgent recommendations are needed to reverse this trend. Recommendations need to be based on solid evidence and specific habitats. Herein, we aimed to investigate the role of an intermediate habitat type between forests and pastures. Wood pastures are key areas for dung beetle conservation. For this reason, we compared dung beetle assemblages among forests, wood pastures, and grasslands. We complemented this with studies on the effects of dung type and season at three Hungarian locations. Pitfall traps baited with cattle, sheep, or horse dung were used in forests, wood pastures, and pasture habitats in spring, summer, and autumn. Dung beetle assemblages of wood pastures showed transient characteristics between forests and pastures regarding their abundance, species richness, Shannon diversity, assemblage composition, and indicator species. We identified a strong effect of season and a weak of dung type. Assemblage composition proved to be the most sensitive measure of differences among habitats. The conservation of dung beetles, and the decomposition services they provide, need continuous livestock grazing to provide fresh dung, as well as the maintenance of wood pastures where dung beetle assemblages typical of forests and pastures can both survive.


Biotropica ◽  
2021 ◽  
Author(s):  
Ita Liana Abdul Rahman ◽  
Sean Yap ◽  
Thary Gazi Goh ◽  
Kai Xin Toh ◽  
Qian Qi Hillary Yee ◽  
...  

Pedobiologia ◽  
2021 ◽  
Vol 85-86 ◽  
pp. 150711
Author(s):  
Jianwei Cheng ◽  
Frank Yonghong Li ◽  
Xinmin Liu ◽  
Xinyu Wang ◽  
Dong Zhao ◽  
...  

2009 ◽  
Vol 69 (1) ◽  
pp. 41-48 ◽  
Author(s):  
FG. Araújo ◽  
MG. Peixoto ◽  
BCT. Pinto ◽  
TP. Teixeira

Cyprinodontiformes fishes (guppies) are widely distributed in Neotropical regions and use deteriorated microhabitats in rivers where few species can occur. This study was carried out in a stretch of the Paraíba do Sul River in bracketing a large urban-industrial complex. The aim was to assess eventual effects that the industrial complex could have on distribution of two closely related fish species of guppies, Phalloceros caudimaculatus and Poecilia reticulata. The area was divided into three zones: Z1, 40 km upriver of the major urban-industrial complex of Volta Redonda; Z2, just down river of the complex; and Z3, 30 km down river of the complex. Six sites (two in each zone) were sampled monthly between November 1998 and October 1999, using a standardized fishing effort with cast net throws, trays lifts and seine hauls, covering different microhabitats, that is, riffles, pools and the proximity of the river's margins. Poecilia reticulata was widely distributed, peaking at Z2, the most polluted area, while P. caudimaculatus showed the highest abundance at Z3, being almost absent in Z1. Both species occurred in high numbers throughout the year but they were scarce between April and June. Females outnumbered males for both species in most size classes and at all sites. Juveniles were more abundant than adults, with non-pregnant females outnumbering pregnant ones. Condition factor was always higher in males than females but only males P. reticulata showed significant difference among the three zones, with the highest values at Z2. The higher number of females confirms the expectation that these species can use very polluted areas and that availability of food provided by organic loads allowed their distribution all over the area. Although these two species have shown indication of spatial separation in the study area, their similar seasonal patterns of occurrence suggest that they respond in a similar way to changes in environmental conditions.


2020 ◽  
Author(s):  
Sebastian Biton-Porsmoguer ◽  
Ricard Bou ◽  
Elsa Lloret ◽  
Manuel Alcaide ◽  
Josep Lloret

AbstractThe status of sardine and anchovy populations in the northern Mediterranean Sea has been declining in recent decades. In this study, fatty acids and parasitism at different reproductive and feeding stages in these two species were assessed using specimens caught along the northern Catalan coast, in order to assess the links between lipid dynamics, reproduction and feeding in these two species, and to contribute towards an explanation of the potential causes of the current situation of the stocks. The results support the use of fatty acid levels as indicators of the body condition of sardine and anchovy at different reproductive and feeding stages, as well as that of the pelagic environmental conditions. In particular, the relatively low n-3 PUFA levels (which are crucial for reproductive success) found in spawning sardines compared to spawning anchovies indicate a poorer reproductive health status of sardine. By comparing the current total lipid content values with those recorded in other Mediterranean and North Atlantic areas, and, others from more than ten years ago, in the adjacent area of the Gulf of Lion, our study reveals the persistent poor condition of sardine and anchovy in the northern Catalan Sea. Furthermore, the low levels of diatom fatty acid markers observed throughout the spawning and non-spawning seasons in both sardine and anchovy, indicate a diet poor in diatoms. Moreover, the results indicate that it is very unlikely that parasitism is a significant factor in the decline in condition of sardine and anchovy in the northern Catalan Sea. In fact, the results suggest that the current poor condition of sardine and anchovy in the northern Catalan Sea has been exacerbated by a decrease in plankton productivity and/or a shift in the taxonomic composition of phytoplankton communities, adding to the ongoing effects of overfishing.


Forests ◽  
2018 ◽  
Vol 9 (9) ◽  
pp. 522 ◽  
Author(s):  
Qiang Liu ◽  
Fengri Li

Understanding the spatial and seasonal variations in leaf physiology is critical for accurately modeling the carbon uptake, physiological processes and growth of entire canopies and stands. For a 17-year-old Larix olgensis Henry plantation, vertical whorl-by-whorl sampling and analyses of seasonally repeated measurements of major photosynthetic parameters were conducted, and the correlations between photosynthetic parameters and environmental conditions, leaf morphological traits and spatial position within the crown were analyzed. According to the correlations, the photosynthetic parameters were standardized based on the environmental conditions to avoid the influence of the changing environment on the patterns of spatial and seasonal variations of photosynthetic parameters. The results showed that the standardized light-saturated net photosynthetic rate (SPmax), standardized dark respiration (SRd) and standardized stomatal conductance under saturated light (Sgs-sat) were all negatively related to the relative depth into the crown (RDINC) throughout the growing season. However, their vertical patterns were different during the development of the phenological phase. In addition, different gradients of environmental conditions also influenced the values and the range of the vertical variation in photosynthesis. High temperature and low humidity usually resulted in smaller values and weaker vertical variations of SPmax and Sgs-sat, but larger values and more obvious vertical variations in SRd. SPmax and Sgs-sat usually exhibited a parabolic seasonal pattern in different vertical positions within the crown; however, SRd generally followed a concave pattern. These seasonal patterns were all weaker with increasing RDINC. Different environments also exhibited a significant influence on the seasonal patterns of photosynthesis. We suggested that standardization is necessary before analyzing spatial and seasonal variations. A single environmental condition could not represent the spatial and seasonal patterns under all gradients of the environment. Spatial and seasonal variations should be simultaneously analyzed because they are related to each other.


2001 ◽  
Vol 9 (2) ◽  
pp. 99-126 ◽  
Author(s):  
Eville Gorham ◽  
Grace S Brush ◽  
Lisa J Graumlich ◽  
Michael L Rosenzweig ◽  
Arthur H Johnson

Paleoecological indicators are examined as to their accuracy in reconstructing past biotic communities and environmental conditions, their utility in answering important questions about such communities and conditions, and the temporal and spatial scales over which they are effective. Next, environmental problems susceptible of paleoecological analysis are considered, as are the ecosystem and landscape properties that can be inferred from such an analysis. The usefulness of paleoecology in anticipating ecological ``surprises'' is then discussed. Finally, a set of conclusions and recommendations is presented.Key words: ecosystem properties, environmental problems, surprise factor.


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