Degradative succession of the insects in small rodents in subtropical systems

We evaluated the insect succession in small rodent carcasses on the soil extracts (surface vs. buried) in two areas (riparian vs. agricultural) and two seasonal periods (spring vs. summer). Daily, the rodent carcasses were weighed and the insects present were collected in them for counting and family level identification. We also measured the air and soil temperature daily, in addition to the physical and chemical characteristics of the soil. The total of 11,059 individuals from 28 taxa was collected. The most abundant taxa were Calliphoridae (70%), Formicidae (20%), Muscidae (2%), and Sarcophagidae (2%). Insect richness was higher in spring in riparian vegetation areas; however, decomposition and insect abundance were greater in spring in agricultural areas by the high temperature measured. Vespidae, Sarcophagidae, Muscidae, and Calliphoridae decreased over time with abundance peaks respectively at 3, 7, 7, and 8 days in riparian vegetation areas. Calliphoridae decreased abundance over time with a peak at five days, but Armadillidiidae increased with peak at 6-9 days in agricultural areas. Decay and insect abundance was high in agricultural areas, mainly on the soil surface. Insect richness was high in riparian vegetation areas, especially on the soil surface. Only the superficial layers of soil presented taxon indicators and all decreased over time with abundance peaks of Calliphoridae, Sarcophagidae, and Muscidae at 5-8, 7, and 7 days, respectively. This abundance peak of insect families help to understand the degradative succession of the insect community in small rodents in subtropical systems of the neotropical region.

Ocupação da Terra e Conflitos de Uso com as Áreas de Preservação Permanente Nativa Remanescente de Cerrado na Sub-bacia do Córrego do Veado, Bacia do Alto Taquari, MS

A conservação das florestas é de grande interesse de toda a sociedade, pois garante os serviços ambientais básicos que sustentam a vida e a economia do país. Nesse estudo, realizou-se um diagnóstico do uso da terra e cobertura vegetal visando avaliar os conflitos entre as atividades antrópicas e as áreas de vegetação nativa remanescente de Cerrado na sub-bacia do Córrego do Veado e propor ações de adequação, do ponto de vista da conservação dos recursos naturais e da biodiversidade, com base na legislação pertinente e nas características físicas da bacia. O estudo se baseou em imagens orbitais e dados vetoriais, processados em Sistema de Informação Geográfica para a geração de produtos cartográficos. Na bacia, foram registradas 81 propriedades rurais, a maioria composta de imóveis com menos de quatro módulos fiscais, onde a principal forma de uso da terra foi a Pastagem sobre áreas consolidadas. A bacia contém em torno de 20% da área coberta por vegetação nativa de Cerrado, porém grande parte das propriedades não apresenta área de Reserva Legal e muitas nascentes de afluentes e do Córrego encontram-se degradadas. As ações propostas referem-se à recuperação das faixas de vegetação ciliar que descumprem o mínimo de largura estabelecido pela legislação, e das áreas de Reserva Legal; à readequação do uso em áreas voltadas à conservação da biodiversidade e à avaliação do potencial turístico da região, como forma de uso sustentável em áreas com alta declividade, solos altamente erodíveis e onde a vegetação de Cerrado encontra-se preservada. The conservation of forests is of great interest to all of society, as it guarantees the basic environmental services that support the life and economy of the country. In this study, a diagnosis of land use and vegetation cover was carried out in order to assess the conflicts between human activities and the areas of native Cerrado remnant in the sub-basin of the Córrego do Veado and propose adaptation actions, from the point of view of the conservation of natural resources and biodiversity, based on the legislation and the physical characteristics of the basin. The study was based on orbital images and vector data, processed in a Geographic Information System for the generation of cartographic products. In the basin, 81 rural properties were registered, the majority consisting of properties with less than four fiscal modules, where the main form of land use was Pasture over consolidated areas. The basin contains around 20% of the area covered by native Cerrado vegetation, however most of the properties do not have a Legal Reserve area and many tributary and stream springs are degraded. The proposed actions refer to the recovery of the strips of riparian vegetation that do not comply with the minimum width established by the legislation, and the areas of Legal Reserve; the readjustment of use in areas aimed at the conservation of biodiversity and the evaluation of the tourist potential of the region, as a form of sustainable use in areas with high declivity, highly erodible soils and where the Cerrado vegetation is preserved.Keywords:River Basin, Conservation, Ecosystem Service, Forest Code.

Structure of riparian vegetation in Bongkasa Pertiwi Village, Abiansemal District, Badung Regency – Bali

Ayung river is the longest river in Bali. The middle part of the river is frequently utilized as rafting for tourism, such as in Bongkasa Pertiwi Village, Abiansemal District, Badung Regency – Bali. To preserve the river’s ecological function, the information of riparian vegetation as the dynamic component in river is highly required. This research aimed to study the structure of riparian vegetation in Bongkasa Pertiwi Village. The plot method was used and the study site was divided into three stations. Each station was composed by three replications with four plot variations: trees (20 x 20 m), poles (10 x 10 m), saplings (5 x 5), and herbs-shrubs (2 x 2 m). The data was analysed using vegetation analysis that completed with Importance Value (IV), Shannon-Wiener Diversity Index (H’), Index of Dominancy (C), and Index of Evenness (E). This study found that the structure of riparian vegetation in Bongkasa Pertiwi Village was in good condition which was indicated by the high abundance of local tree species. The floristic composition of riparian vegetation comprised by 18 species of trees, 18 species of poles, 21 species of saplings, and 29 species of herbs and shrubs. Cocos nucifera, Pterospermum javanicum, Bischofia javanica, Cananga odorata, Elaeocarpus serratus, Artocarpus heterophyllus, Coffea canephora, and Nephelium lappaceum were the species with the highest Importance Value (IV). The floor vegetation in form of herbs and shrubs was dominated by Sphaegneticola trilobata, Oplismenus burmanni, and Diplazium esculentum. Based on the Diversity Index (H’), Index of Dominancy (C), and Index of Evenness (E), diversity of riparian vegetation in Bongkasa Pertiwi Village was classified as medium category, without any dominated species, and the vegetation composition was equivalent.

Nesobasis rito sp. nov. (Zygoptera: Coenagrionidae), a new species of forest damselfly from Vanua Levu, Fiji

Nesobasis rito sp. nov. (Holotype ♂, Fiji, Vanua Levu, Drawa, 31 v 2018, A. Rivas-Torres leg.) from the comosa group is here described, illustrated, diagnosed, and compared with morphologically close species of the genus. Nesobasis rito can be distinguished from its related congeners by the shape of the caudal appendages and the ligula. The most similar species are N. comosa and N. heteroneura, which, like N. rito, have the caudal appendages covered by dense setae (especially the first species), but the shape differs clearly in lateral view, with N. rito having longer and more slender appendages, and a basal tooth clearly seen in dorsal view, absent in other members of the comosa group. The specific status of the collected specimens is also supported by the results of genetic analyses, where N. rito appears as a well-supported monophyletic clade. Nesobasis rito also has a distinct distribution from its most similar congeners: it is found on Vanua Levu, while N. comosa is found on Viti Levu and the closely related N. heteroneura is found on Viti Levu and Ovalau. All species of this group are found in streams with native forest riparian vegetation on their respective islands.

Riparian Vegetation Density Mapping of an Extremely Densely Vegetated Confined Floodplain

The most crucial function of lowland-confined floodplains with low slopes is to support flood conveyance and fasten floods; however, obstacles can hinder it. The management of riparian vegetation is often neglected, though woody species increase the vegetation roughness of floodplains and increase flood levels. The aims are (1) to determine the branch density of various riparian vegetation types in the flood conveyance zone up to the level of artificial levees (up to 5 m), and (2) to assess the spatial distribution of densely vegetated patches. Applying a decision tree and machine learning, six vegetation types were identified with an accuracy of 83%. The vegetation density was determined within each type by applying the normalized relative point density (NRD) method. Besides, vegetation density was calculated in each submerged vegetation zone (1–2 m, 2–3 m, etc.). Thus, the obstacles for floods with various frequencies were mapped. In the study area, young poplar plantations offer the most favorable flood conveyance conditions, whereas invasive Amorpha thickets and the dense stands of native willow forests provide the worst conditions for flood conveyance. Dense and very dense vegetation patches are common in all submerged vegetation zones; thus, vegetation could heavily influence floods.