Snake conservation in anthropized landscapes: considering artificial habitats and questioning management of semi-natural habitats

2020 ◽  
Vol 66 (3) ◽  
Author(s):  
Eric Graitson ◽  
Sylvain Ursenbacher ◽  
Olivier Lourdais
2019 ◽  
Vol 12 (1) ◽  
pp. 204 ◽  
Author(s):  
Yang Cao ◽  
Yosihiro Natuhara

Riparian areas are local hot spots of biodiversity that are vulnerable and easily degraded. Comparing plant communities in habitats with different degrees of urbanization may provide valuable information for the management and restoration of these vulnerable habitats. In this study, we explored the impact of urbanization on vegetation communities between artificial and semi-natural habitats within two rivers with different levels of development. We compared species richness, types of vegetation, and composition patterns of the plants in our study. In artificial habitats, the sites with relatively high levels of urbanization had the highest species richness, while in semi-natural habitats, the highest species richness was recorded in the less urbanized sites. Furthermore, every component of urbanization that contributed to the variation of species richness was examined in the current study. In artificial habitats, the proportion of impervious surface was the strongest predictor of the variation in species richness and was associated with the richness of alien, native, and riparian species. In semi-natural habitats, most of the richness of alien and native species were associated with the distance to the city center, and the number of riparian and ruderal species was significantly related to the proportion of impervious surface. Moreover, we found that a high level of urbanization was always associated with a large abundance of alien and ruderal species in both artificial and in semi-natural habitats. We recommend the methods of pair comparison of multiple rivers to analyze the impact of urbanization on plant species in riparian areas and have suggested various management actions for maintaining biodiversity and sustainability in riparian ecosystems.


2016 ◽  
Vol 67 (1) ◽  
pp. 131 ◽  
Author(s):  
Louise B. Firth ◽  
Freya J. White ◽  
Meredith Schofield ◽  
Mick E. Hanley ◽  
Michael T. Burrows ◽  
...  

Coastal defences are proliferating in response to climate change, leading to the creation of more vertical substrata. Efforts are being made to mitigate their impacts and create novel habitats to promote biodiversity. Little is known about the effect of aspect (i.e. north–south directionality) and inclination on intertidal biodiversity in artificial habitats. Artificial and natural habitats were compared to assess the role of aspect and substratum inclination in determining patterns of biodiversity at two tidal heights (high and mid). We also compared grazing activity between north- and south-facing surfaces in natural habitats to examine the potential for differential grazing pressure to affect community structure and functioning. Results were variable but some clear patterns emerged. Inclination had no effect on biodiversity or abundance. There was a general trend towards greater taxon richness and abundance on north-facing than south-facing substrata in natural and artificial habitats. On natural shores, the abundance and grazing activity of ‘southern’ limpets (i.e. Patella depressa) was greater on south-facing than north-facing substrata, with possible implications for further range-expansion. These results highlight the importance of incorporating shaded habitats in the construction of artificial habitats. These habitats may represent an important refuge from grazing pressure and thermal and desiccation stress in a warming climate.


2022 ◽  
Vol 8 ◽  
Author(s):  
Ruolin Li ◽  
Yu Guo ◽  
Chuanxin Qin ◽  
Shuo Zhang ◽  
Dongping Ji ◽  
...  

Artificial habitat deployment can restore natural habitats or supplement existing natural habitats. The effect of resource proliferation and protection is obvious. However, few reports have addressed the biological community association between artificial habitats and adjacent environments. Here, Illumina sequencing of 18S rDNA was performed, and the diversity, community structure, and co-occurrence networks of protists in different layers of artificial reefs (ARs) and adjacent seawater (WAR) were described to verify that constructing ARs in Bailong Pearl Bay improves local spatial heterogeneity and functional diversity. In terms of the degree of species interaction, the protist communities were ranked as follows: surface and bottom of WAR > ARs and WAR > different layers of ARs. The α-diversity of protists associated with ARs and WAR decreased with an increase in depth. Protist diversity was greater in WAR than in ARs. β-Diversity analysis revealed significant differences in protist community structure between WAR and ARs (P < 0.05), and the upper layers of ARs and the middle or bottom layers of ARs differed. The key topological features of protist networks showed more positive interspecific interactions in the AR-associated protist community, a higher degree of niche differentiation, and higher complexity and stability. The keystone protists in the bottom seawater layer displayed community functions that were biased toward initial fixation in the ocean carbon cycle. The AR-associated protist community tended to participate in carbon transfer in the food chain and decomposition and utilization of dissolved organic matter (DOM). This study revealed significant differences in protist community structure between ARs and the adjacent environment, and the ecological functions of the key phyla were found to be related. In conclusion, protist communities in WAR may provide food sources for AR-associated heterotrophic protists. A variety of key phyla associated with ARs have biological roles in the carbon pump via their ecological characteristics.


2021 ◽  
Vol 8 ◽  
Author(s):  
Ferrante Grasselli ◽  
Laura Airoldi

Marine infrastructures are increasing, generating a variety of impacts and introducing artificial habitats which have low ecological value and support assemblages that differ significantly from those on natural rocky coasts. While in the past there was little ecological consideration as to how artificial structures were built, now the trend is to look for “greener” designs inspired by or mimicking nature. These greening efforts have had a strong focus on enhancing physical habitat structure to support more diverse assemblages, driven by the untested assumption that artificial habitats lack the physical structure proper to natural habitats. We tested this assumption by comparing five descriptors of physical structure (inclination; exposure; roughness; abundance, and diversity of surface morphological microelements) across a combination of natural and artificial habitats of regular and irregular morphologies (seawalls = artificial regular; cliffs = natural regular; breakwaters = artificial, irregular; and boulder fields = natural irregular) in the North Adriatic Sea. Most structural descriptors were similar between artificial and natural habitats. Only inclination was consistently steeper in the artificial than in the natural habitats. Other minor differences in roughness or in the abundance of some surface microelements were related to the general morphology (regular or irregular) of the habitat rather than to its artificial or natural identity. The outcomes challenge the widespread assumption that artificial habitats lack the physical structure proper to natural habitats and stimulate renewed consideration about other structural and non-structural elements that could enhance the performance and sustainability of artificial marine structures, such as construction material, environmental setting or maintenance. They also encourage a wider reflection about what makes an artificial building surface “greener”: structural complexity is an important ecological parameter, and its deliberate increase will lead to responses in the biota, however, this may not necessarily match “more natural” conditions.


2017 ◽  
Vol 68 (3) ◽  
pp. 473 ◽  
Author(s):  
Pedro Henrique Cipresso Pereira ◽  
Marcus Vinicius Bezerra dos Santos ◽  
Daniel Lino Lippi ◽  
Pedro Henrique de Paula Silva ◽  
Breno Barros

The present study tested the hypothesis that artificial habitats (pier and bridge) harbour different fish trophic guilds compared with natural habitats (mangrove roots) and that the trophic structure of fish communities on estuarine artificial habitats resembles adjacent coral reefs. High-definition cameras were used to survey the fish community associated with the different structures over a 6-month period. Benthos was also analysed following the point intercept method on the different habitats. In the estuary, fish abundance was up to threefold higher and species richness twofold higher on artificial structures compared with the natural habitat. Mangrove roots were mainly inhabited by juvenile carnivores, whereas the pier and bridge were mostly inhabited by sessile invertebrate feeders and roving herbivores. A less diverse benthic community was found on mangrove roots, mostly composed of mud and algae. In contrast, benthos at the bridge and pier was more diverse and dominated by sponges, octocorals and oysters. In addition, fish trophic structure from an adjacent coral reef area showed more than 60% similarity with the fish community on the artificial structures surveyed. The results of the present study indicate that artificial hard structures support unique fish communities compared with natural estuarine mangrove habitats.


2020 ◽  
Vol 12 (3) ◽  
pp. 15364-15369
Author(s):  
Animesh Talukdar ◽  
Bivash Pandav ◽  
Parag Nigam

Interactions between wildlife and livestock have increased over time with increased anthropogenic pressure on limited available natural habitats.  These interactions have resulted in sharing of pathogens between the species resulting in impacting the wild animals’ fitness and reproduction and further influencing their abundance and diversity.  The spatial overlap between Swamp Deer and livestock was studied at Jhilmil Jheel Conservation Reserve (JJCR), Uttarakhand and Kishanpur Wildlife Sanctuary (KWLS), Uttar Pradesh in India, having different levels of interaction with livestock.  The prevalence, load and commonality of gastro-intestinal parasites in the species was studied through coprological examination. Parasitic ova of Strongyle sp., Trichostrongylus sp., Fasciola sp., and Moniezia sp. Amphistomes were encountered in swamp deer and livestock from both the sites. The parasitic species richness and prevalence however, varied between JJCR and KWLS.  The study recorded significant differences between the parasitic load in Swamp Deer with the eggs per gram of 487.5±46.30 at JJCR and 363.64±49.97 at KWLS at varying levels of livestock interactions.


Larvae of many marine invertebrates must capture and ingest particulate food in order to develop to metamorphosis. These larvae use only a few physical processes to capture particles, but implement these processes using diverse morphologies and behaviors. Detailed understanding of larval feeding mechanism permits investigators to make predictions about feeding performance, including the size spectrum of particles larvae can capture and the rates at which they can capture them. In nature, larvae are immersed in complex mixtures of edible particles of varying size, density, flavor, and nutritional quality, as well as many particles that are too large to ingest. Concentrations of all of these components vary on fine temporal and spatial scales. Mechanistic models linking larval feeding mechanism to performance can be combined with data on food availability in nature and integrated into broader bioenergetics models to yield increased understanding of the biology of larvae in complex natural habitats.


Agronomy ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 205
Author(s):  
Stefanos Kostas ◽  
Stefanos Hatzilazarou ◽  
Elias Pipinis ◽  
Anastasios Vasileiadis ◽  
Panagiotis Magklaras ◽  
...  

Pistacia lentiscus L. is a dioecious shrub or small tree with high drought resistance, native in the entire Mediterranean basin. The variety ‘Chia’ (mastic tree) is cultivated for the production of mastic gum (a resin produced after wounding of the trunks and thick branches) in the Island of Chios (Greece), but it also has a significant ornamental value. In the present study, ten male and ten female genotypes of P. lentiscus var. Chia from the natural habitats of Chios were selected and examined with respect to the rooting efficiency of their shoot cuttings. The germination ability of the seeds was also tested. The 20 plants were morphologically described, mainly with respect to traits related to their ornamental value. Furthermore, leaves were collected from the 20 genotypes, from which genomic DNA (gDNA) was isolated, followed by amplification of gDNA fragments using the polymerase chain reaction (PCR) and inter simple sequence repeat (ISSR) primers. This was done aiming both at the determination of their genetic distance and the establishment of possible correlations between the amplified bands and certain morphological traits. The results of the study showed that there were differences among the genotypes for both methods of propagation. Regarding the rooting of the shoot cuttings, the best genotype was 8M (cv. ‘Psilophyllos’), achieving a rooting rate of 62.5% in winter with the application of indolebutyric acid (potassium salt of IBA), while regarding the seed germination capacity the genotype 2F exhibited the highest germination rate (57%). Genetic analysis using ISSRs separated the plants into four groups, one group consisting of male genotypes, one of the female genotypes, one consisting of members from both genders and a fourth containing a single male genotype. The genetic analysis of the male genotypes only produced a dendrogram showing the cultivars clustering in three different groups. Regardless of the genetic analysis, it seems that there were correlations between the ISSR markers and the leaf traits and also the gender and the asexual propagation. These correlations can assist future breeding programs of P. lentiscus var. Chia.


Insects ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 701
Author(s):  
Lorenzo Tonina ◽  
Giulia Zanettin ◽  
Paolo Miorelli ◽  
Simone Puppato ◽  
Andrew G. S. Cuthbertson ◽  
...  

The strawberry blossom weevil (SBW), Anthonomus rubi, is a well-documented pest of strawberry. Recently, in strawberry fields of Trento Province (north-east Italy), new noteworthy damage on fruit linked to SBW adults was observed, combined with a prolonged adult activity until the autumn. In this new scenario, we re-investigated SBW biology, ecology, monitoring tools, and potential control methods to develop Integrated Pest Management (IPM) strategies. Several trials were conducted on strawberry in the laboratory, field and semi-natural habitats. The feeding activity of adult SBW results in small deep holes on berries at different stages, causing yield losses of up to 60%. We observed a prolonged survival of newly emerged adults (>240 days) along with their ability to sever flower buds without laying eggs inside them in the same year (one generation per year). SBW adults were present in the strawberry field year-round, with movement between crop and no crop habitats, underlying a potential role of other host/feeding plants to support its populations. Yellow sticky traps combined with synthetic attractants proved promising for both adult monitoring and mass trapping. Regarding control, adhesive tapes and mass trapping using green bucket pheromone traps gave unsatisfactory results, while the high temperatures provided by the black fabric, the periodic removal of severed buds or adults and Chlorpyrifos-methyl application constrained population build-up. The findings are important for the development of an IPM strategy.


Pathogens ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 352
Author(s):  
Wei Wei ◽  
Valeria Trivellone ◽  
Christopher H. Dietrich ◽  
Yan Zhao ◽  
Kristi D. Bottner-Parker ◽  
...  

Phytoplasmas are obligate transkingdom bacterial parasites that infect a variety of plant species and replicate in phloem-feeding insects in the order Hemiptera, mainly leafhoppers (Cicadellidae). The insect capacity in acquisition, transmission, survival, and host range directly determines the epidemiology of phytoplasmas. However, due to the difficulty of insect sampling and the lack of follow-up transmission trials, the confirmed phytoplasma insect hosts are still limited compared with the identified plant hosts. Recently, quantitative polymerase chain reaction (qPCR)-based quick screening of 227 leafhoppers collected in natural habitats unveiled the presence of previously unknown phytoplasmas in six samples. In the present study, 76 leafhoppers, including the six prescreened positive samples, were further examined to identify and characterize the phytoplasma strains by semi-nested PCR. A total of ten phytoplasma strains were identified in leafhoppers from four countries including South Africa, Kyrgyzstan, Australia, and China. Based on virtual restriction fragment length polymorphism (RFLP) analysis, these ten phytoplasma strains were classified into four distinct ribosomal (16Sr) groups (16SrI, 16SrIII, 16SrXIV, and 16SrXV), representing five new subgroups (16SrI-AO, 16SrXIV-D, 16SrXIV-E, 16SrXIV-F, and 16SrXV-C). The results strongly suggest that the newly identified phytoplasma strains not only represent new genetic subgroup lineages, but also extend previously undiscovered geographical distributions. In addition, ten phytoplasma-harboring leafhoppers belonged to seven known leafhopper species, none of which were previously reported insect vectors of phytoplasmas. The findings from this study provide fresh insight into genetic diversity, geographical distribution, and insect host range of phytoplasmas. Further transmission trials and screening of new potential host plants and weed reservoirs in areas adjacent to collection sites of phytoplasma harboring leafhoppers will contribute to a better understanding of phytoplasma transmission and epidemiology.


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