scholarly journals Trophic level and edge history modulate the depth of edge influence

2019 ◽  
Vol 2 ◽  
Author(s):  
Tibor Magura ◽  
Bela Tóthmérész
Keyword(s):  
Edge Effect ◽  
Trophic Level ◽  
Ground Beetle ◽  
Ground Beetles ◽  
Optimal Size ◽  
Natural Habitats ◽  
Predator Species ◽  
Depth Of Edge Influence ◽  
The Impact ◽  
Edge Influence

Habitat edges are increasingly important worldwide because of forest fragmentation and the loss of natural habitats. Reduction in habitat area, increased isolation of fragments are considered to be the primary cause of species decline and extinction in fragmented landscapes. Edge effect is a key determinant, since most effects of fragmentation attributed to patch area may be scaled-up edge effect. Moreover, the isolation of patches is basically determined by the filter function (permeability) of edges. The distance that edge effects extend into the adjacent core (interior) habitat (the depth of edge influence, DEI) is a central issue in edge studies, as it fundamentally influences environmental properties, composition and structure of core habitats, all which significantly control species occurrences. Most previous studies on DEI neglected the impact of origin and the processes maintaining edges, although the structural and functional properties of edges determined by their history may modulate the permeability of edges, and consequently DEI. Evaluating available information on ground beetles (Coleoptera: Carabidae) in forest edges, we show that both species traits and edge history affect DEI on ground beetles. We found that DEI on abundance of herbivore, omnivore and predator ground beetle species is similar in natural edges, and edges maintained by agriculture, while it is generally penetrated over greater distances into the forests across edges repeatedly disturbed by forestry or other anthropogenic interventions than across edges maintained by natural processes. We found extreme edge effect across edges under forestry activities, as DEI on abundance of predator species is penetrated into the forest interiors up to ≤ 300 m. According to our findings DEI is more pronounced for predators and across edges created and maintained by forestry operations, suggesting outstanding sensitivity of higher trophic level organisms to fragmentation caused by forestry activities. Our result suggests that in planning the optimal size and shape of fragments for ecosystem-based forest management, to provide a core zone, a minimum area of 50 ha of circular forest fragments is required for maintaining an intact ground beetle assemblage.

scholarly journals The Impact of Climate Variations on the Structure of Ground Beetle (Coleoptera: Carabidae) Assemblage in Forests and Wetlands

Forests ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 1074
Author(s):  
Marina Kirichenko-Babko ◽  
Yaroslav Danko ◽  
Anna Musz-Pomorksa ◽  
Marcin K. Widomski ◽  
Roman Babko
Keyword(s):  
Negative Impact ◽  
Ground Beetle ◽  
Ground Beetles ◽  
Climate Variations ◽  
Wet Season ◽  
Dry Period ◽  
Drought Period ◽  
Terrestrial Arthropods ◽  
Climate Aridization ◽  
The Impact

We studied the effect of climate variations on the structure of the assemblage of ground beetles (Coleoptera: Carabidae) in a wetland and surrounding watershed forest. We analyzed the changes in the structure of the assemblage of ground beetles provoked by a two-year dry period against the background of studies carried out during the two-year wet period. Aridization influenced the structure of the assemblage of ground beetles more in wetlands than in forests. It was shown that despite the stabilizing effect of the forest on the structure of assemblages of terrestrial arthropods, the two-year dry period had a negative impact on the assemblage of ground beetles in the studied area. The Simpson dominance index of 4.9 during the wet season increased to 7.2 during the drought period. Although the total number of species during the dry period did not significantly decrease in comparison with the wet period—from 30 to 27 species—changes occurred in the trophic structure: during the drought period, the number of predators decreased. It is concluded that the resistance of forest habitats to climate aridization is somewhat exaggerated and, very likely, the structure of the community of arthropods in forests will change significantly.

scholarly journals Ground beetles in city forests: does urbanization predict a personality trait?

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4360 ◽  
Author(s):  
Wiebke Schuett ◽  
Berit Delfs ◽  
Richard Haller ◽  
Sarah Kruber ◽  
Simone Roolfs ◽  
...  
Keyword(s):  
Ground Beetle ◽  
Ground Beetles ◽  
Exploratory Behaviour ◽  
Natural Habitats ◽  
Forest Patches ◽  
Behavioural Responses ◽  
Personality Differences ◽  
First Response ◽  
Second Year ◽  
One Year

Background Urbanization leads to substantial changes in natural habitats with profound effects on wildlife. Understanding behavioural responses to such environmental change is essential for identifying which organisms may adapt, as behaviour is often the first response to altered conditions. Individuals in more urbanized habitats may be expected to be more exploratory and bolder than their conspecifics in less urbanized habitats as they may be better able to cope with novel challenges. Methods In a two-year field study we tested ground beetles from differently urbanized forests for their exploratory behaviour (in a novel environment) and their risk-taking (death-feigning). In total, we tested ca. 3,000 individuals of four forest-dwelling ground beetle species from eight within-city forest patches. In the second year, we also transferred ca. 800 tested individuals of two species to the laboratory to test for consistent behavioural differences (i.e. personality differences) under standardised conditions. Results Individuals were generally more exploratory in more urbanized than in less urbanized areas but only in one year of the study. Exploratory behaviour was not predicted by population density but increased with temperature or showed a temperature optimum. Exploration was consistent over time and individuals that were more exploratory also took higher risks. Discussion We demonstrated that species which are generally less directly exposed to human activities (e.g., most invertebrates) show behavioural responses to urbanization. Effects of urbanization were year-dependent, suggesting that other environmental conditions interacted with effects of urbanization on beetle behaviour. Furthermore, our results indicate that different personality compositions might cause behavioural differences among populations living in differently urbanized habitats.

scholarly journals Effect of plant protection on assemblages of carabid beetles (Coleoptera, Carabidae) in beetroot crops in four-year rotation

2019 ◽  
Vol 2 ◽  
Author(s):  
Agnieszka Kosewska ◽  
Katarzyna Nijak ◽  
Mariusz Nietupski ◽  
Renata Kędzior
Keyword(s):  
Species Richness ◽  
Plant Protection ◽  
Ground Beetle ◽  
Plant Protection Products ◽  
Ground Beetles ◽  
Chemical Plant ◽  
Carabid Beetles ◽  
Arable Fields ◽  
Set Up ◽  
The Impact

Ground beetles (Col., Carabidae) are common predators in agrocenoses. A number of plant pests occurring on arable fields become their feed. Therefore, they contribute to a natural reduction of the occurrence of pests. In addition, they are well-known bioindicators used, among others to determine the state of the habitats and the impact of human activity on entomofauna. In the fields, the use of chemical plant protection products is a very controversial activity. The aim of the study was to investigate assemblages of ground beetles occupying conventional and organic sugar beetroot crops. Therefore, to determine the impact of the application of pesticides on the assemblages of these useful beetles was made. The study was conducted at the Agricultural Experimental Station in Winna Góra near Środa Wielkopolska in Poland from May till September of 2004, 2008, 2012 and 2016. The experiment was carried out in the field with organic crop of sugar beet, and in the crop, for which an integrated plant protection programme was planned. The area of each field was 0.5 ha. Modified Barber traps were used to catch insects. On each of the selected fields 10 pitfalls were set up, which were emptied every 14 days. Within 4 years of the study a total of 11865 specimens belonging to 52 ground beetle species were recorded. 5582 specimens belonging to 50 species and 6283 specimens belonging to 46 species were caught in the fields under chemical protection and organic, respectively. On a multiannual scale, there were no statistically significant differences in the number of individuals and species of Carabidae on conventional and organic fields. Fluctuation in ground beetles abundance and species richness were observed dependent on the year of study but not of the treatment. Harpalus rufipes was the most represented species in all fields. The main conclusion is that using chemical plant protection on a multiannual scale does not adversely affect the number and species richness of ground beetles.

scholarly journals The impact of reduced tillage and distance to field margin on predator functional diversity

2022 ◽  
Author(s):  
Stine K. Jacobsen ◽  
Lene Sigsgaard ◽  
Anna B. Johansen ◽  
Kristian Thorup-Kristensen ◽  
Per M. Jensen
Keyword(s):  
Functional Diversity ◽  
Ground Beetles ◽  
Soil Disturbance ◽  
Reduced Tillage ◽  
Pitfall Traps ◽  
Natural Habitats ◽  
Activity Density ◽  
Soil Disturbances ◽  
Abundance And Diversity ◽  
The Impact

Abstract Introduction Agricultural intensification results in biodiversity loss through land conversion and management practices which negatively impact arthropods. The abundance and diversity of ground-dwelling predators, e.g. ground beetles (Coleoptera: Carabidae) and spiders (Araneae), are negatively affected by soil disturbances such as tillage. Reducing soil disturbances can potentially conserve arthropod populations in the field and reduce the use of chemical pest controls. The present study investigated the ground-dwelling predatory community using pitfall traps in cereal fields with three different levels of soil disturbance: conventional tillage, reduced tillage and no tillage under Conservation Agriculture management, in 2018 and 2019. Pitfall traps were placed in transects from the field margins. Overall, the activity-density of ground-dwelling predators was higher in fields with minimum soil disturbance and generally declined with increased distance to semi-natural habitats. Functional diversity, expressed by the body size of ground beetles, was also affected by soil disturbances; large ground beetles more consistently occurred in CA, while few or none of the largest ground beetles were found in RT and CT. A higher sample-heterogeneity in less disturbed fields was indicated by a more variable median and higher skewness in the number of predators in those fields. In 2019 only, species diversity was higher along field edges bordering semi-natural habitats when compared to the cropped area. Our results show that reduced tillage supports predator arthropod communities at a local scale: It also bolsters agro-ecosystem resilience by promoting a higher activity-density and by increasing the heterogeneity and functional diversity of ground-dwelling predators. Implications for insect conservation The results obtained in the present study show that soil disturbances significantly influence arthropod abundance and diversity. Conservation of epigeic natural enemies in the agricultural landscape is improved by reducing soil-disturbing events such as tillage.

Nickel oxide nanoparticles induce genotoxicity and cellular alterations in the ground beetle Blaps polycresta (Coleoptera: Tenebrionidae)

2021 ◽  
pp. 074823372110009
Author(s):  
Dalia Abdel Moneim Kheirallah ◽  
Awatef Mohamed Ali ◽  
Salah Eldein Osman ◽  
Amal Mohamed Shouman
Keyword(s):  
Nickel Oxide ◽  
Structural Changes ◽  
Ground Beetle ◽  
Biological Tissues ◽  
Treated Group ◽  
Sublethal Dose ◽  
Oxide Nanoparticles ◽  
Nickel Oxide Nanoparticles ◽  
Nio Nps ◽  
The Impact

Nickel nanoparticles (Ni-NPs) have advantageous applications in the industry; however, little is known of their adverse effects on biological tissues. In the present study, the ground beetle Blaps polycresta was employed as a sensitive indicator for nickel oxide nanoparticles (NiO-NPs) toxicity. Adult male beetles were injected with six dose levels of NiO-NPs (0.01, 0.02, 0.03, 0.04, 0.05, and 0.06 mg/g body weight). Mortality was reported daily over 30 days under laboratory conditions to establish an LD50. Nickel was detected in the testicular tissues of the beetles using X-ray analysis and transmission electronic microscopy. Beetles treated with the sublethal dose of 0.02 mg/g were selected to observe molecular, cellular, and subcellular changes. Gene transcripts of HSP70, HSP90, and MT1 were found to be increased >2.5-, 1.5-, and 2-fold, respectively, in the treated group compared with the controls. Decreased gene expression of AcPC01, AcPC02, and AcPC04 (≤1.5-, ≤2-, and < 2.5-fold, respectively, vs. controls) also were reported in the treated group. Under light microscopy, various structural changes were observed in the testicular tissues of the treated beetles. Ultrastructure observations using scanning and transmission electron microscopy showed severe damage to the subcellular organelles as well as deformities of the heads and flagella of the spermatozoa. Therefore, the present study postulated the impact of NiO-NPs in an ecological model.

scholarly journals Assessing Habitat Vulnerability and Loss of Naturalness: Applying the GLOBIO3 Model in the Czech Republic

2021 ◽  
Vol 13 (10) ◽  
pp. 5355
Author(s):  
Vilém Pechanec ◽  
Ondřej Cudlín ◽  
Miloš Zapletal ◽  
Jan Purkyt ◽  
Lenka Štěrbová ◽  
...  
Keyword(s):  
Land Use ◽  
Czech Republic ◽  
Habitat Quality ◽  
Species Abundance ◽  
Biodiversity Loss ◽  
Infrastructure Development ◽  
Natural Habitats ◽  
The Czech Republic ◽  
New Equation ◽  
The Impact

Global and regional biodiversity loss is caused by several drivers including urban development, land use intensification, overexploitation of natural resources, environmental pollution, and climate change. The main aim of our study was to adapt the GLOBIO3 model to the conditions of the Czech Republic (CR) to assess loss of naturalness and biodiversity vulnerability at the habitat level on a detailed scale across the entire CR. An additional aim was to assess the main drivers affecting the biodiversity of habitat types. The GLOBIO3 model was adapted to CZ-GLOBIO by adapting global to local scales and using habitat quality and naturalness data instead of species occurrence data. The total mean species abundance (MSA) index of habitat quality, calculated from the spatial overlay of the four MSA indicators by our new equation, reached the value 0.62. The total value of MSA for natural and near-natural habitats was found to be affected mainly by infrastructure development and fragmentation. Simultaneously, intensity of land use change and atmospheric nitrogen deposition contributed primarily to the low total value of MSA for distant natural habitats. The CZ-GLOBIO model can be an important tool in political decision making to reduce the impact of the main drivers on habitat biodiversity in the CR.

scholarly journals Evaluating the Impact of Two Generalist Predators on the Leafhopper Erasmoneura vulnerata Population Density

Insects ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 321
Author(s):  
Stefan Cristian Prazaru ◽  
Giulia Zanettin ◽  
Alberto Pozzebon ◽  
Paola Tirello ◽  
Francesco Toffoletto ◽  
...  
Keyword(s):  
Field Experiments ◽  
Field Studies ◽  
Generalist Predators ◽  
Predator Species ◽  
Potted Plants ◽  
Naturally Occurring ◽  
Orius Majusculus ◽  
Limited Effectiveness ◽  
Pest Outbreaks ◽  
The Impact

Outbreaks of the Nearctic leafhopper Erasmoneura vulnerata represent a threat to vinegrowers in Southern Europe, in particular in North-eastern Italy. The pest outbreaks are frequent in organic vineyards because insecticides labeled for organic viticulture show limited effectiveness towards leafhoppers. On the other hand, the naturally occurring predators and parasitoids of E. vulnerata in vineyards are often not able to keep leafhopper densities at acceptable levels for vine-growers. In this study, we evaluated the potential of two generalist, commercially available predators, Chrysoperla carnea and Orius majusculus, in suppressing E. vulnerata. Laboratory and semi-field experiments were carried out to evaluate both species’ predation capacity on E. vulnerata nymphs. The experiments were conducted on grapevine leaves inside Petri dishes (laboratory) and on potted and caged grapevines (semi-field); in both experiments, the leaves or potted plants were infested with E. vulnerata nymphs prior to predator releases. Both predator species exhibited a remarkable voracity and significantly reduced leafhopper densities in laboratory and semi-field experiments. Therefore, field studies were carried out over two growing seasons in two vineyards. We released 4 O. majusculus adults and 30 C. carnea larvae per m2 of canopy. Predator releases in vineyards reduced leafhopper densities by about 30% compared to the control plots. Results obtained in this study showed that the two predators have a potential to suppress the pest density, but more research is required to define appropriate predator–prey release ratios and release timing. Studies on intraguild interactions and competition with naturally occurring predators are also suggested.

scholarly journals Sensory-based niche partitioning in a multiple predator–multiple prey community

2015 ◽  
Vol 282 (1808) ◽  
pp. 20150520 ◽  
Author(s):  
Jay J. Falk ◽  
Hannah M. ter Hofstede ◽  
Patricia L. Jones ◽  
Marjorie M. Dixon ◽  
Paul A. Faure ◽  
...  
Keyword(s):  
Species Interactions ◽  
Prey Species ◽  
Niche Partitioning ◽  
Signal Evolution ◽  
Signal Design ◽  
Predator Species ◽  
Mate Attraction ◽  
Communication Signals ◽  
Signal Features ◽  
The Impact

Many predators and parasites eavesdrop on the communication signals of their prey. Eavesdropping is typically studied as dyadic predator–prey species interactions; yet in nature, most predators target multiple prey species and most prey must evade multiple predator species. The impact of predator communities on prey signal evolution is not well understood. Predators could converge in their preferences for conspicuous signal properties, generating competition among predators and natural selection on particular prey signal features. Alternatively, predator species could vary in their preferences for prey signal properties, resulting in sensory-based niche partitioning of prey resources. In the Neotropics, many substrate-gleaning bats use the mate-attraction songs of male katydids to locate them as prey. We studied mechanisms of niche partitioning in four substrate-gleaning bat species and found they are similar in morphology, echolocation signal design and prey-handling ability, but each species preferred different acoustic features of male song in 12 sympatric katydid species. This divergence in predator preference probably contributes to the coexistence of many substrate-gleaning bat species in the Neotropics, and the substantial diversity in the mate-attraction signals of katydids. Our results provide insight into how multiple eavesdropping predator species might influence prey signal evolution through sensory-based niche partitioning.

scholarly journals Design of Cell-Based Flotation Circuits under Uncertainty: A Techno-Economic Stochastic Optimization

Minerals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 459
Author(s):  
Seyed Hassan Amini ◽  
Aaron Noble
Keyword(s):  
Circuit Design ◽  
Net Present Value ◽  
Structure Identification ◽  
Optimal Size ◽  
Flotation Kinetics ◽  
Deterministic Models ◽  
Kinetic Coefficients ◽  
Study Results ◽  
Circuit Structure ◽  
The Impact

The design of cell-based flotation circuits is often completed in two distinct phases, namely circuit structure identification and equipment sizing selection. While recent literature studies have begun to address the implications of stochastic analysis, industrial practice in flotation circuit design still strongly favors the use of deterministic metallurgical modeling approaches. Due to the complexity of the available mathematical models, most flotation circuit design techniques are constructed based on deterministic models. Neglecting the impact of various sources of uncertainty may result in the identification of circuit solutions that are only optimal in a narrow region of specific operating scenarios. One promising strategy to address this shortcoming is through the Sample Average Approximation (SAA) methodology, a stochastic approach to handling uncertainty that has been widely applied in other disciplines such as supply chain and facility location management problems. In this study, a techno-economic optimization algorithm was formulated to select the optimal size and number of flotation cells for a fixed circuit structure while considering potential uncertainty in several input parameter including feed grade, kinetic coefficients, and metal price. Initially, a sensitivity analysis was conducted to screen the uncertain parameters. After simplifying the optimization problem, the SAA approach was implemented to determine the equipment configuration (i.e., cell size and number) that maximizes the plant’s net present value while considering the range of potential input values due to parameter uncertainty. The SAA methodology was found to be useful in analyzing uncertainty in flotation kinetics; however, the approach did not provide a useful means to assess the influence of uncertainties in ore grade and metal price, as these values are not significant in determining equipment size but rather influence the optimal circuit structure, which was not considered in this study. Results from an application example indicate that the SAA approach produces optimal solutions not initially identified in a deterministic optimization, and these SAA solutions tend to provide greater robustness to uncertainty and variation in the flotation kinetics.

scholarly journals Invasive Scots Pine, Pinus sylvestris, Replacing Corema, Corema conradii, Heathland in the Annapolis Valley, Nova Scotia

2005 ◽  
Vol 119 (2) ◽  
pp. 237 ◽  
Author(s):  
Paul M. Catling ◽  
Susan Carbyn
Keyword(s):  
Pinus Sylvestris ◽  
Scots Pine ◽  
Vascular Plants ◽  
Dominant Species ◽  
Vascular Plant ◽  
Agricultural Crops ◽  
Deschampsia Flexuosa ◽  
Natural Habitats ◽  
Annapolis Valley ◽  
The Impact

Examination of air photos from 1930, 1970 and 2002 revealed stands of the European Scots Pine (Pinus sylvestris) invading remnants of natural Corema (Corema conradii) heathland in the Annapolis valley. To document the impact of the introduced pines, four natural habitats were compared with two adjacent habitats already invaded by the pines. All surveyed habitats had been dominated by Corema heath based on air photos taken in 1930. Twenty 1 m2 quadrats were used to record presence and cover of vascular plants at each site. The invasive alien pines reduce the native cover to 12%. Vascular plant biodiversity is reduced to less than 42% and the cover of the heathland dominant, Corema conradii, is reduced from over 100 % to less than 2%. with Deschampsia flexuosa becoming the dominant species. The modified ecosystem and loss of biodiversity has economic impacts through loss of pollinators of agricultural crops and loss of germplasm of native crop relatives.

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