Complex effects of acidification, habitat properties and fish stock on littoral macroinvertebrate assemblages in montane standing waters

Littoral macroinvertebrates in acidified waterbodies are affected by the interaction of acidification and local environmental conditions. Understanding the interplay of these factors in the structuring of communities is essential for interpreting responses to and/or recovery from acidification. Here, we analyse the species composition and richness of littoral macroinvertebrates in a range of acidified montane standing waters in relation to water chemistry, littoral characteristics and fish stock. The main species composition gradients were related to pH and conductivity; however, considerable variation along these gradients was associated with local habitat characteristics (changing water levels and littoral structure) and concentration of ionic aluminium and dissolved organic carbon. Although fish stock effects were confounded by correlated acidity, we observed a significant decline in abundance of macroinvertebrates vulnerable to fish predation at sites with fish stock. Overall, littoral macroinvertebrates of acidic waterbodies were diverse due to the heterogeneity of local habitat properties, despite they were dominated by acid-tolerant species. Acidic humic sites with dense, heterogeneous littoral vegetation were species-rich, hosting numerous habitat specialists and rare species, while chronically acidified lakes with high aluminium concentrations and sparse littoral vegetation had species-poor assemblages, characteristic of strong acid-stress. Water level manipulation resulted in serious assemblage impoverishment, overriding the effects of more favourable water chemistry. This study shows that the littoral fauna of acidic waterbodies is structured by complex effects induced by local factors in addition to acidity, resulting in acid-stressed assemblages with relatively high variability, emphasising a need to analyse local habitat factors when evaluating the impact of acidification on macroinvertebrates.

The Effect of Habitat Structural Complexity on Gastropods in Anarid Mangrove Wetland

Structural complexity of mangrove forests are thought to provide critical habitats for a variety of invertebrates. We studied the influence of mangrove structure and seasonality on the gastropod diversity in the extreme mangrove ecosystem of the Persian Gulf. Sampling was conducted in two successive years (February and June 2018, February and June 2019) at two mangrove habitats i.e., pneumatophore zone and mudflats. The communities were characterized by the dominance of specific taxa and the comparably low species richness. In total, 18 taxa were identified, including 14 species occurring in the mangrove forest and 16 species in the mudflats. Assimineidae dominated the community in both mangrove habitats. Mean density of gastropods was 1.5-fold higher in the pneumatophore zone (86.12±135.21 ind.m-2) than in the mudflats (54.33±108.69 ind.m-2). Species such as Haminoea vitrea, Peronia verruculata, Assiminea mesopotamica and Platevindex tigrinus were found to benefit from the presence of pneumatophores, which highlights the importance of local habitat complexity. Gastropod communities varied significantly between the habitats, but there was little difference in the community structure between seasons. Distance-based linear models revealed that total organic carbon and total organic nitrogen best explained the variation in gastropods community structure.

Community Composition of Bacteria Isolated from Swiss Banknotes Varies Depending on Collection Environment

Humans interact constantly with surfaces and associated microbial communities in the environment. The factors shaping the composition of these communities are poorly understood: some proposed explanations emphasize the influence of local habitat conditions (niche-based explanations), while others point to geographic structure and the distance among sampled locations (dispersal-based explanations). However, the relative roles of these different drivers for microbial community assembly on human-associated surfaces are not clear. Here, we used a combination of sampling, sequencing (16S rRNA) and culturing to show that the composition of banknote-associated bacterial communities varies depending on the local collection environment. Using banknotes collected from various locations and types of shops across Switzerland, we found taxonomic diversity dominated by families such as Pseudomonadaceae, Staphylococcaceae and Streptococcaceae, but with banknote samples from particular types of shops (especially butcher shops) having distinct community structure. By contrast, we found no evidence of geographic structure: similarity of community composition did not decrease with increasing distance among sampled locations. These results show that microbial communities associated with banknotes, one of the most commonly encountered and exchanged human-associated surfaces, can reflect the local environmental conditions (in this case, the type of shop), and the signal for this type of variation was stronger than that for geographic structure among the locations sampled here.

Half of the Ancient Trees in Hungary Stand in Human-Altered Environments

Big trees contribute to various ecosystem functions and spiritual values are given to them by local people, yet they are endangered. We compiled the health status, accessibility, and local habitat categories of the 2000 biggest (considering girth) trees in Hungary in 531 settlements. A total of 1550 specimens belong to 29 indigenous species, while 450 are non-indigenous (43 species). Most of them stand in a forest or park (not as a solitary tree), in the North Hungarian Range. Altogether, half of the ancient trees in Hungary stand in human-altered environments. Three-quarters are in a fair health condition. However, only 10.3% of the biggest white willows and 24.5% of the biggest sweet chestnuts are in good or excellent condition. A number of 121 big trees should no longer be listed in the nationwide online database because they died, or no longer reach the girth criteria (e.g., due to breakage). This number proves that any kind of documentation is important. More than half of the trees are easily accessible, while 9% are very difficult to reach. Only a very few big trees receive legal protection at the local or national level, on their own or in the habitat where they stand.

Study of Plankton diversity status of local habitat in eastern Uttar Pradesh

The studies included the local habitat of Lake River and ponds, which are most important, share the habitat in local flora and fauna in eastern Uttar Pradesh (U.P.) India. The study was conducted to assess the mainly phytoplankton and zooplankton status of the Ramgarh lake, Maheshra tal, and Rapti river in Gorakhpur district of Uttar Pradesh, India by examining the biological parameters. The most important planktonic group encountered in the present study was cyanophyceae and Zygnematophyceae Nostocale and Desimidiale encountered as other genera which existed in the Ramgarh lake, Maheshra tal, and Rapti river water of the habitat. The study found that the members of protozoans group animal contribute 50 percent of the total zooplankton population during the year of the study period.

Differential Response of Migratory Guilds of Birds to Urbanization

Species richness and density of native fauna in urban parks and greenspaces (“parks”) is often lower than in surrounding areas. Understanding the causes of these differences requires a hierarchical approach that integrates factors across multiple scales. In 2003 we surveyed bird communities in 48 forested parks in Portland, Oregon, USA, to identify the relative contributions of park size, shape, and connectivity, landscape composition, and variation in local habitat to differences in richness and density of long-distance migrant, short-distance/partial migrant, and resident birds. All surveyed parks contained highly structured understories comprised primarily of native vegetation and lacked development beyond trails. The bird guilds responded differently to environmental factors. Richness and density of long-distance migrants increased with park area and the abundance of small, mostly native, tree species. Resident species richness also increased with the abundance of small trees. Richness of residents and short-distance migrants was independent of park area, and resident density declined with increasing park area. Park shape, connectivity, and landscape composition did not contribute to differences in richness or density of different migratory guilds. Most long-distance migrants were forest-dependent species. An analysis of all forest-dependent species of all migratory guilds suggested that few exist in parks below 10 ha, and minimum area requirements for maintaining populations of forest-dependent species are estimated to be 30 to 40 ha. Without such parks most long-distance migrants would likely disappear from Portland’s landscape.

The state of Moldavian viper (Vipera Ursinii Moldavica) in the context of the action plan for their conservation (annexed to the Bern convention)

Based on the generalization of data from previous publications and own results, regarding the distribution of Meadow Viper (Vipera ursini) in the Dniester - Prut interfluve, the current species state in the context of the Action Plan for conservation, annexed to the Bern Convention, is characterized. The need to complex study of local habitat status and to take measures for their conservation is discussed. The influence of some anthropogenic and climatic factors upon the habitats and the problems of their conservation in the current conditions of agrolandscape are analyzed.

Local Habitat Characteristics Determine Butterfly Diversity and Community Structure in a Threatened Kihansi Gorge Forest, Southern Udzungwa Mountains, Tanzania

Background Many species inhabiting Kihansi gorge ecosystem in Southern Udzungwa mountains, Tanzania are threatened with extinction due to habitat loss caused by constructed hydropower plant that diverted over 90% of the water off the Kihansi River. Understanding ecological correlates and structure of an animal community in perturbed ecosystems is an important way to enhancing species conservation particularly in this system where several species are already threatened with extinction. This study assessed influences of local habitat characteristics on the butterfly abundance, species richness and diversity and examined how the butterfly community structures across three structurally heterogeneous habitats in the Kihansi gorge forest. Butterfly abundance data were collected using baited traps and measured environmental variables in the field where trapping occurred. To understand the diversity and butterfly richness, these parameters were computed under Primer software. Non-metric multidimensional scaling and analysis of community similarity were used to analyse the butterfly community structure. Further, the generalized linear models were used to assess how the measured variables explained observed species diversity, abundance, and richness. Results In total, 72 species of butterfly in five families were recorded. Butterfly, species diversity and richness did not vary across the habitat types or elevation gradient but showed strong correlation with some habitat characteristics. Also, there was evidence of butterfly communities structuring into distinct groups that showed greater separation associated with the habitat characteristics they utilise. Further, across the study area, butterfly species diversity was mostly likely to increase in high canopy and in trees with smaller diameter at breast height and at lower ground cover. Similarly, abundance significantly increased in the woodland and wooded grassland habitats, where there was high canopy and where tree density was high. Furthermore, butterfly species richness was strongly positively associated with high canopy cover and was mostly likely to increase in sites closer to water source. Conclusion Assessing habitat correlates of the butterfly communities provide important information on what components of the habitats are most useful to target when planning conservation especially in threatened ecosystems. This also helps to reveal existing gaps in important knowledge that would be useful to improving long-term monitoring of biodiversity in in fragile systems such as the Kihansi gorge forest.