Zoosporic true fungi and heterotrophic straminipiles assemblages from soil of Brazilian Cerrado areas

The influence of seasonal fluctuations and environmental factors on the occurrence and distribution of zoosporic true fungi and heterotrophic straminipiles in terrestrial ecosystems is poorly understood. This contribution analyses the species composition, frequency, abundance and diversity of zoosporic true fungi and heterotrophic straminipiles assemblages from two areas of Cerrado in the State of São Paulo, Brazil. Samples of soil were collected at four dates during the rainy and dry seasons. Twenty-one abiotic factors were measured. The assemblages showed a high diversity and evenness and were represented by 30 taxa of Chytridiomycota and Oomycota. Some abiotic factors appeared to have influenced the patterns of distribution and occurrence of the taxa in different areas and/or seasons. Even so, the biotic factors (richness, diversity indices and evenness) and the Sorensen index showed high similarity between the assemblages.     

Impacts of antemortem ingestion of alcoholic beverages on insect successional patterns

This paper studies the impacts of antemortem ingestion of alcoholic beverages by the domestic rabbit, Oryctolagus cuniculus L., on postmortem successional patterns of insects during winter and summer 2018 in Riyadh, Saudi Arabia. Insect samples were collected from the carcasses of rabbits fed alcoholic beverages as well as untreated rabbits for 15 days postmortem during two successional studies in each season. The results showed that, during both seasons, the decomposition process for the carcasses of rabbits fed alcoholic beverages antemortem was one to two days longer. The results also showed, however, that alcoholic beverages did not affect insect succession patterns in either season. In fact, the number of insects appeared to be influenced by the ambient temperature during the two seasons, with 4415 insects in the winter compared to 1033 insects in the summer. In total, 30 insect taxa were collected during the winter study from the carcasses of rabbits fed alcoholic beverages antemortem; while 26 of these same taxa were collected from the carcasses of the untreated rabbits. Among the treated rabbits, those fed 25 ml alcoholic beverages treated attracted the highest number of insect taxa (24 taxa). In the summer study, 21 insect taxa were collected in total, 19 from the carcasses of the alcohol-treated rabbits and 13 from untreated rabbits. Among the treated rabbits, those fed 50 ml alcoholic beverages attracted the highest number of insect taxa (14 taxa). These results contribute to the understanding of the factors affecting the use of insects in medical investigations, given that alcoholic beverages are a common addictive agent.     

Occurrence and distribution of zoosporic organisms in water bodies from Brazilian Cerrado

Zoosporic organisms are commonly found in different aquatic ecosystems; however little is known about the influence of environmental factors and seasonal fluctuations on their occurrence and distribution. This study investigated patterns of abundance, frequency and diversity of these organisms and their relationship with some abiotic factors and seasonality in a cerrado remnant in Sao Paulo, Brazil. Water samples were collected at four dates in two areas of this remnant during the rainy and dry seasons, and 13 abiotic factors were analyzed. From 48 samples collected, 32 taxa were isolated with the multiple baiting technique. The community structure of the zoosporic organisms showed some changes in response to different spatial distribution and seasonal fluctuations, probably influenced by distinct abiotic characteristics of each area or climatic period. Still, the similarity between areas and seasons indicated by S?rensen index and diversity (richness, evenness, Shannon and Simpson indices) were high.     

The role of carrion-frequenting arthropods in the decay process

Abstract. 1. The various groups of arthropods associated with rodent carrion during decay in temperate woodland and grassland habitats are described in each of four seasons.
2. A distinction is drawn between those occurring by chance and those positively associated with the carrion.
3. The role of these last in actually assisting the decay of the carcasses with which they are found is discussed. Despite the abundance and diversity of carrion-frequenting species, few are involved to any significant extent in the release of carrion materials during decomposition.     

Contrasting diversity dynamics of phoretic mites and beetles associated with vertebrate carrion

Carrion is an ephemeral and nutrient-rich resource that attracts a diverse array of arthropods as it decomposes. Carrion-associated mites often disperse between animal carcasses using phoresy, the transport of one species by another. Yet few studies have contrasted the dynamics of mite assemblages with other insect taxa present at carrion. We examined and compared the changes in abundance, species richness and composition of mite and beetle assemblages sampled at kangaroo carcasses in a grassy eucalypt woodland at four different times over a 6-month period. We found that the majority of mites were phoretic, with the mesostigmatid genera Uroseius (Uropodidae), Macrocheles (Macrochelidae) and Parasitus (Parasitidae) the most abundant taxa (excluding astigmatid mites). Abundance and richness patterns of mites and beetles were very different, with mites reaching peak abundance and richness at weeks 6 and 12, and beetles at weeks 1 and 6. Both mites and beetles showed clear successional patterns via changes in species presence and relative abundance. Our study shows that mesostigmatid mite assemblages have a delay in peak abundance and richness relative to beetle assemblages. This suggests that differences in dispersal and reproductive traits of arthropods may contribute to the contrasting diversity dynamics of carrion arthropod communities, and further highlights the role of carrion as a driver of diversity and heterogeneity in ecosystems.     

Beetles and flies collected on pig carrion in an experimental setting in Thuringia and their forensic implications

Decomposition processes and insect succession were analysed on a total of eight pig (Sus scrofa) carcasses. The survey was carried out in four different periods between November 2007 and August 2008 and on two different substrates (meadow, concrete floor close to a building). The experiments were placed in a rural site in the surroundings of Jena, Thuringia. The duration and specificity of the different decomposition stages were dependent on season, weather and quality and quantity of insect colonization. Whereas the carrion maintained a bloated appearance even after 133 days in winter, it reached the dry stage within 8 days in the summer months. The type of substrate had few effects on the decaying process, but the insects were generally more abundant on the meadow. In total, more than 57 species of Diptera belonging to 17 families and 48 species of Coleoptera belonging to 14 families were identified. Dominant species belonged to the families of Calliphoridae (n = 11 spp.), Sarcophagidae (n = 8), Muscidae (n = 9), Piophilidae (n = 3), Silphidae (n = 6), Dermestidae (n = 3), Nitidulidae (n = 4), Cleridae (n = 3) and Histeridae (n = 2). Remarkably, the rather common Nicrophorus species were completely absent, whereas the usually rare Necrodes littoralis (L.) was present in larger numbers. No distinct coincidence between the occurrence of a single species and a certain decomposition stage could be confirmed. A main objective of the study is the establishment of a forensic entomological database for Central Europe, especially Thuringia.     

埃塞俄比亚Alatish国家公园大型哺乳动物多样性、分布及其与栖息地的联系

于2004年8月-2005年3月间研究了Alatish国家公园在雨季和旱季期间大型哺乳动物的多样性和分布.基于地形图、卫片和预调查结果,在4种生境类型中识别出37个100 km2或者更小的斑块.在4个植被类型中随机选择了11个斑块,沿随机选择的样线进行了调查,样线10 km 长,0.2 km宽,覆盖了该区域面积的20%.使用Shannon-Wiener多样性指数、DISTANCE 5.0 软件以及 Simpson相似性指数分析了大型哺乳动物的多样性以及分布的相似性.记录了20种体型较大的哺乳动物;河边林地在雨季和旱季都有最高的多样性,林地的多样性最低;旱季中4种类型的栖息地具有相似的分布型;由于栖息地退化不能确定物种的分布格局.联合距离取样分析揭示出,旱季和雨季大型哺乳动物的密度较低,分别为4.067只/km2和6.263只/km2.所观察的哺乳动物可分为草食动物(15%)、游牧动物(30%)、杂食动物(25%)与食肉动物(30%).     

Successional Patterns of Microfungi in Fallen Leaves of Ficus pleurocarpa (Moraceae) in an Australian Tropical Rain Forest1

Successional patterns of microfungi on decaying leaves of Ficus pleurocarpa were assessed as part of a study to enumerate microfungi in tropical rain forest leaf litter. Leaves degraded into fragments over a period of 3 mo. Two methods were applied, a direct observational method and a particle filtration protocol. Using a direct method, 104 species were observed, while 53 sporulating taxa and 100 sterile morphotaxa were isolated by particle filtration. Overall patterns of succession were confirmed by both methods, but the relative abundance of species detected differed between the two methods. Nonmetric Multidimensional Scaling identified at least four successional stages and suggested that microfungal communities increased in similarity with advancing decay. Data collected by the direct method indicated a slow but steady decline of diversity with advancing decay, whereas an increase in diversity was detected by particle filtration. Synecological succession studies provide a useful tool to identify patterns and generate hypotheses. Understanding the underlying causes of successional patterns will require further autecological studies.     

Effects of carrion decomposition on litter arthropod assemblages

1. Many organisms contribute to the decomposition of carrion. For arthropods, many studies focus on the necrophagous community, those directly consuming carrion.
2. Necrophagous arthropods use carrion as a shelter or food source. Therefore, carrion generally increases the abundance and biodiversity of necrophagous species. However, it is unclear if carrion has similar effects on detrital communities.
3. This study examines changes in community structure and composition of necrophilous and detrital communities over the course of decomposition.
4. Five pig head carrion were placed at least 7 m apart under cages in temperate mixed forest. Leaf litter was sampled 0 m, 1.5 m, and 3 m from each carrion weekly during summer, and monthly during autumn, until the first frost. Arthropods were extracted from leaf litter by using Berlese funnels.
5. At the carrion site, necrophagous insects increased in abundance, species richness, and Shannon diversity during decomposition, and all decreased after dry decay.
6. Detritus arthropods displayed a sharp increase in abundance during advanced decay, decreasing during dry decay, and a general increase over time for species richness and diversity.
7. In conclusion, carrion can influence the surrounding, non-necrophagous arthropod community, highlighting the need to investigate carrion effects beyond typical necrophagous species to have a more holistic understanding of carrion ecology.

     

Carrion beetles succession in three different habitats in Riyadh,Saudi Arabia

A main objective of the study is the establishment of a forensic entomological database for Riyadh, Saudi Arabia. Decomposition processes and beetle succession were analysed on rabbit carcasses in three different habitats (agricultural, desert and urban) in the period from May to July 2014. Due to the effects of the high temperature at the study sites, carrion reached the dry stage within 12 days in the agricultural habitat, and 6 days in the desert and urban habitats. A total of 125 beetles belonging to eight species and five families were collected during the decaying process, with their abundances increasing from the fresh to decay stages. The prevailing species belonged to the families of Dermestidae and Histeridae. It was not possible to confirm any definitive relationship between the occurrence of a single species and a particular stage of decomposition. The beetle communities were also not distinctively different between desert and urban habitats, but a distinct community was evident in the agriculture habitat. In addition, there were distinct beetle communities between the decay stage and the other stages. The dry stage recorded the lowest number of beetles. This study indicated that, the habitat type had an effect on the decay process and the abundance rate of the beetles.     

Assessing insect biodiversity with automatic light traps in Brazil: Pearls and pitfalls of metabarcoding samples in preservative ethanol

Automated species identification based on data produced with metabarcoding offers an alternative for assessing biodiversity of bulk insect samples obtained with traps. We used a standard two‐step PCR approach to amplify a 313 bp fragment of the barcoding region of the mitochondrial COI gene. The PCR products were sequenced on an Illumina MiSeq platform, and the OTUs production and taxonomic identifications were performed with a customized pipeline and database. The DNA used in the PCR procedures was extracted directly from the preservative ethanol of bulk insect samples obtained with automatic light traps in 12 sampling areas located in different biomes of Brazil, during wet and dry seasons. Agricultural field and forest edge habitats were collected for all sampling areas. A total of 119 insect OTUs and nine additional OTUs assigned to other arthropod taxa were obtained at a ≥97% sequence similarity level. The alpha and beta diversity analyses comparing biomes, habitats, and seasons were mostly inconclusive, except for a significant difference in beta diversity between biomes. In this study, we were able to metabarcode and HTS adult insects from their preservative medium. Notwithstanding, our results underrepresent the true magnitude of insect diversity expected from samples obtained with automatic light traps in Brazil. Although biological and technical factors might have impacted our results, measures to optimize and standardize eDNA HTS should be in place to improve taxonomic coverage of samples of unknown diversity and stored in suboptimal conditions, which is the case of most eDNA samples.     

Relationships between the Seasonal Variations of Macroinvertebrates,and Land Uses for Biomonitoring in the Xitiaoxi River Watershed,China

The impacts of differences in watershed land uses, and differences in seasonality on benthic macroinvertebrate communities, were evaluated in 12 stream sites within the Xitiaoxi River watershed, China, from April 2009 to January 2010. The composition of macroinvertebrate community differed significantly among three land use types. Forested sites were characterized by high taxa richness, diversity and the benthic‐index of biotic integrity (B‐IBI), while farmland and urban disturbed stream sites presented contrary patterns. The percentage of urban land use, conductivity, dissolved oxygen, ammonia nitrogen and total phosphorus were the major drivers for the variations. The land use related water quality stress gradients of the four sampling seasons were determined by means of four independent Principal Component Analyses. The responses of macroinvertebrate community metrics, to anthropogenic stressors, were explored using Spearman Rank Correlation analyses. All the selected metrics, including total numbers of taxa, numbers of Ephemeroptera, Plecoptera and Trichoptera taxa, percentage of non‐insect abundance, percentage of scrapers abundance, Pielou’s evenness index, Simpson diversity index, and the Benthic Index of Biotic Integrity were correlated significantly with environmental gradients (PC1) in autumn. In other seasons such correlations were less pronounced. Our results imply that autumn is the optimal time to sample macroinvertebrate communities, and to conduct water quality biomonitoring in this subtropical watershed. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Carrion flies of forensic interest: a study of seasonal community composition and succession in Lisbon,Portugal

Information on Diptera community, seasonality and successional patterns in every geographical region is fundamental for the use of flies as forensic indicators of time of death. In order to obtain these data from the Lisbon area (Portugal), experiments were conducted during the four seasons of the year, using piglet carcasses as animal models. Five stages were recognized during the decomposition process. The stages, besides visually defined, could be separated taking into account the occurrence and abundance of the specific groups of Diptera collected. In general, the bloated stage recorded higher abundance and species‐richness values. Seventy‐one species were identified, belonging to 39 families, in a total of 20 144 adult Diptera collected. Autumn yielded the highest values of species richness, whereas winter had the lowest. In all seasons of the year, Calliphoridae was the dominant family; Muscidae and Fanniidae were very abundant as well. Calliphora vicina Robineau‐Desvoidy, Calliphora vomitoria (Linnaeus), Chrysomya albiceps (Wiedemann), Lucilia ampullacea Villeneuve, Lucilia caesar (Linnaeus), Lucilia sericata (Meigen) (Calliphoridae), Hydrotaea ignava (Harris), Muscina prolapsa (Harris), Synthesiomyia nudiseta (van der Wulp) (Muscidae), Piophila megastigmata McAlpine, Stearibia nigriceps (Meigen) (Piophilidae) and Nemopoda nitidula (Fallén) (Sepsidae) were revealed to be very important members of the Diptera community collected. The necrophagous behaviour, demonstrated by their immatures, using carrion as a food source makes them useful forensic indicator species. Also of relevance is the presence of Chrysomya megacephala (Fabricius), S. nudiseta and P. megastigmata, foreign species established in the local carrion communities. This study also marks the first record of S. nudiseta in Portugal.     

高原鼠兔肠道微生物中丰富及稀有类群的季节性特征

气候及食物是驱动植食性小哺乳动物肠道菌群产生季节性变化的重要因素。然而,此类研究很少涉及肠道丰富及稀有微生物类群。本文以高原鼠兔（Ochotona curzoniae）为对象,通过16S rRNA基因测序和分析,探讨丰富及稀有肠道微生物类群的结构组成、多样性指数及功能在春、夏、秋、冬四季的变化特征。结果显示,丰富类群对菌群主要门和功能的季节性变异贡献大于稀有类群,稀有类群对菌群OTU和alpha多样性的变异贡献大于丰富类群。丰富类群和稀有类群的香农指数均在冬季显著高于其他季节;丰富类群的ACE指数在秋季显著低于其他季节,而稀有类群的ACE指数则在冬季显著高于春季和夏季。丰富类群中拟杆菌门（Bacteroidetes）的相对丰度在冬季和秋季显著高于春季和夏季,但在稀有类群中,夏季和秋季的相对丰度显著高于冬季和春季。丰富类群中氨基酸代谢通路的相对丰度在冬季显著高于春季和夏季,而在稀有类群中,其相对丰度在春季显著高于夏季和秋季。气温、降水量和植被中的营养物质与肠道菌群中丰富类群和稀有类群的变化均显著相关,环境变量对丰富类群和稀有类群变化的总解释率分别为18%（气温：3%;降水：4%;植被营养成分：10%;联合：1%）和9%（气温：1%;降水：2%;植被营养成分：5%;联合：1%）。以上结果表明肠道微生物中的丰富和稀有类群具有不同的分布模式和季节性特征,二者对整体菌群变异的贡献存在差异,环境因素更多地影响丰富类群,反映了肠道微生物不同类群对季节变化响应的非一致性。本研究增进了我们对哺乳动物肠道菌群季节性变化过程及环境适应性的认识。     

Phytoplankton diversity (alpha,beta, and gamma) from the Araguaia River tropical floodplain lakes (central Brazil)

Alpha, beta and gamma are three components of species diversity. Knowing these attributes in floodplain lake phytoplankton communities is vital when selecting conservation areas. Species diversity is commonly used with other taxonomic groups, but rarely with phytoplankton. We compared the number of phytoplankton species (alpha diversity) from 21 Middle Araguaia River floodplain lakes in the 2000 and 2001 rainy and dry seasons. From these samples we estimated complete survey species richness (gamma diversity), quantified differences in species composition between lakes (beta diversity) and assessed the influence of abiotic variables on beta diversity. We recorded a total of 577 taxa. The Sjack1 estimator indicated that 62.31% of taxa were sampled in the 2000 rainy and 67.65% dry seasons, and 68.36% in the 2001 rainy and 73.5% dry seasons. In almost all seasons, alpha diversity negatively correlated with latitude. Beta diversity (β-1) was higher in high water periods, especially in 2000. This may have been caused by isolated heavy rainfall, which would have increased environmental heterogeneity and raised beta diversity. DCA showed differences in phytoplankton composition between rainy and dry seasons in 2000 and 2001, reflecting the influence of flood pulses on phytoplankton composition. The Mantel test indicated spatial distribution patterns where geographically more distant lakes had less-similar phytoplankton communities. Handling editor: J. Padisak     

Insects Associated with Pig Carrion in Two Environments of the Brazilian Savanna

Studies of carrion fauna have increased in Brazil and have contributed to the knowledge of this fauna in the national territory. Brazil has continental dimensions and presents various biomes in its territorial area. Most of the carrion fauna have seldom been studied, and this is especially true for the Savanna or “Cerrado.” The present research examined the fauna visiting carrion in two environments and two seasons in a rural area situated in a region of Cerrado in southeastern Brazil. The two environments studied were a pasture and a fragment of semi-deciduous forest. Samples were collected during the dry and humid seasons of the year. The study identified the diversity and relative abundance of species attracted to pig carcasses (Sus scrofa L.) exposed in each environment and season. Eight pig carcasses (10 ± 1 kg) were placed in traps, and adult insects attracted to the traps were collected during the decay of the carcasses. A total of 92,489 insects were collected during the experiments. The Diptera was the most frequent order (92.2%) represented by 27 families and at least 124 species. This was followed by Coleoptera (4.4%) represented by 14 families and at least 65 species. Sarcophagidae had the greatest diversity of species, followed by Muscidae and Calliphoridae. Several species were collected only during a specific period of the year or in a single environment. The results are important from an ecological point of view and for Medico-Legal Forensic Entomology.     

广州市越秀公园鸟类多样性与保护对策

对广州市越秀公园鸟类的多样性进行了调查,共记录鸟类43种,隶属8目20科。其中留鸟27种,夏候鸟2种,冬候鸟8种,其它繁殖鸟6种。对夏冬季及不同生境的鸟类群落特征进行比较分析,得到夏季鸟类的数量、密度、优势度都比冬季高,而多样性指数和均匀性指数却比冬季低;南秀湖畔大草坪、金印游乐场、竹林、南秀树林、南秀湖和环市路旁6种生境中鸟类的种类、数量和多样性差异较大,以金印游乐场鸟类的多样性最高。根据公园内不同环境鸟类多样性状况提出了保护对策。     

滇西北藏区草地管理方式对草地昆虫群落多样性的影响

采用野外样地生态方法研究了4种不同管理草地的昆虫群落的多样性。结果表明,草地昆虫群落优势类群为叶蝉总科、盲蝽科、蝇科、瘿蚊科等;刈草草地、种植草地、自由放牧草地和灌丛草地拥有的昆虫的科数分别为40、44、35和36,个体数分别为1869、1510、997和848;刈草草地昆虫群落多样性指数相对较高。用Jaccard相似性系数(ISJ)判别发现,4种管理方式草地昆虫群落处于中等相似水平。因此,不同管理方式对昆虫群落的多样性有影响,传统管理的刈草草地有利于维持草地昆虫的多样性。     

Traits reveal ecological strategies driving carrion insect community assembly

1. The succession of carrion-associated (necrophilous) insects on decomposing carrion is well documented. To exploit the changing nutritious and dynamic resources available throughout the carrion decomposition process, different species colonise and consume carrion in a predictable temporal sequence. The traits of these necrophilous insects should reflect their ecological strategies. Morphological traits of these insects, such as body size and wing size, however, have not previously been examined during active and advanced decomposition. 2. We used fourth-corner multivariate generalised linear models to identify insect community morphological trait patterns and to quantify their change through time on decomposing rabbit carcasses in grassland and woodland environments. 3. We found that larger-bodied species of flies and carrion-specialist beetles were associated with the early stages of decomposition. The morphological traits of ants, in contrast, showed no changes at carcasses through time and instead showed body size differences between grassland and woodland environments. 4. Our findings indicate that specialist flies and beetles that arrive early in the decomposition process possess traits that enable rapid discovery of carrion at a large scale. Generalist beetles and ants do not share this same trait and are instead adapted to locate and consume a wider variety of resources in their preferred habitat type at their local scale. 5. Our results provide insights into the morphological adaptations linked to the ecological strategies of distinct components of carrion insect communities. Further, our results offer insights into the community assembly dynamics that structure the communities of necrophilous insect species.     

Positive and negative impact to decomposition of pig cadavers by ants (hymenoptera: Formicidae) at the Islet Yeongdo in Busan,South Korea

We observed how ants affected the decomposition process of pig cadavers. Experiments were carried out with six pig cadavers during three seasons without winter. Fifteen ant species belonging to 14 genera 3 subfamilies were recorded from pig cadavers. The species richness and species composition of ants were different significantly at bloated and decay stages from the remaining stages, regardless of season. Ant species Nylanderia flavipes, Aphaenogaster japonica, Pheidole fervida, and Ectomomyrmex javanus kept hunting a considerable amount of eggs and maggots of flies in the two stages. In particular, Lasius japonicus continually interrupted landing and ovipositing of flies and removed eggs and maggots from pig cadavers. Our observation suggests that ants may affect decomposition process of dead animals by participating in positive and negative ways by massive removal of eggs and maggots of flies.