High‐quality genomes reveal significant genetic divergence and cryptic speciation in the model organism Folsomia candida (Collembola)

The collembolan Folsomia candida Willem, 1902, is an important representative soil arthropod that is widely distributed throughout the world and has been frequently used as a test organism in soil ecology and ecotoxicology studies. However, it is questioned as an ideal “standard” because of differences in reproductive modes and cryptic genetic diversity between strains from various geographical origins. In this study, we present two high-quality chromosome-level genomes of F. candida, for the parthenogenetic Danish strain (FCDK, 219.08 Mb, N50 of 38.47 Mb, 25,139 protein-coding genes) and the sexual Shanghai strain (FCSH, 153.09 Mb, N50 of 25.75 Mb, 21,609 protein-coding genes). The seven chromosomes of FCDK are each 25–54% larger than the corresponding chromosomes of FCSH, showing obvious repetitive element expansions and large-scale inversions and translocations but no whole-genome duplication. The strain-specific genes, expanded gene families and genes in nonsyntenic chromosomal regions identified in FCDK are highly related to its broader environmental adaptation. In addition, the overall sequence identity of the two mitogenomes is only 78.2%, and FCDK has fewer strain-specific microRNAs than FCSH. In conclusion, FCDK and FCSH have accumulated independent genetic changes and evolved into distinct species since diverging 10 Mya. Our work shows that F. candida represents a good model of rapidly cryptic speciation. Moreover, it provides important genomic resources for studying the mechanisms of species differentiation, soil arthropod adaptation to soil ecosystems, and Wolbachia-induced parthenogenesis as well as the evolution of Collembola, a pivotal phylogenetic clade between Crustacea and Insecta.

Impact of Environmental Conditions and Management on Soil Arthropod Communities in Vineyard Ecosystems

The importance of soil biodiversity and soil-based ecosystem services in the context of viticulture has recently been emphasized. Over 85% of soil fauna species richness is represented by edaphic arthropod communities. Edaphic arthropod responses to soil characteristics and management practices can be considered as good bioindicators of soil quality. Here, 168 soil samples that were collected from 2014 to 2019 in several vineyards of different Italian wine-growing areas were analyzed to explore how arthropod communities respond to several factors that are characteristic of vineyard ecosystems. The analysis of the combined effects of the primary abiotic variables (the chemical and physical characteristics of soil) and management practices (organic vs. conventional, soil inter-row management) on soil biological quality (assessed by QBS-ar index) identified soil temperature and soil texture as the abiotic factors exerting the most significant effect on the QBS-ar values. Organic vineyards exhibited higher QBS-ar values compared to those of conventionally managed vineyards, and subsoiling negatively influenced the soil biological quality.

Soil Arthropods in the Douro Demarcated Region Vineyards: General Characteristics and Ecosystem Services Provided

Viticulture is one of the oldest and most profitable forms of agriculture; it is also one of the most intensive farming systems. As intensive cultivation threatens the environment, there is increasing interest in the concept of sustainability within the wine industry, as well as new business opportunities, as customers begin to pay more attention to environmental and sustainability issues. Recognizing the key role of soil quality in environmentally and economically sustainable viticulture makes it essential to understand better soil arthropod communities, given their crucial functions in maintaining soil quality and health. The ‘Douro Demarcated Region’ (DDR) in northern Portugal offers good potential, in regards to biodiversity, due to its significant areas of non-crop habitats. This work aims to compile information on soil arthropod communities (both soil surface and soil-living) collected in the DDR vineyard agroecosystems. A description of the ecosystem services provided by them, as a basis for the development and implementation of sustainable viticulture systems, is also an objective of this work. An important set of soil arthropods necessary for the delivery of vital ecosystem services for viticulture, with particular reference to supporting and regulating services, occurred in this ecosystem. Eight classes were chiefly represented in a sample of about 167,000 arthropod specimens: Arachnida, Chilopoda, Diplopoda, Entognatha, Insecta, Malacostraca, Pauropoda, and Symphyla. The most representative were Entognatha and Insecta in soil-surface arthropods, and Arachnida and Entognatha in soil-living arthropods. The presence of recognized groups as bioindicators in agroecosystems, such as soil quality indicators, is also revealed. This knowledge is expected to contribute to a more efficient and sustainable management of the viticultural ecosystem.

Impact of 2-years practice of organic coffee farming on soil arthropod diversity

Organic farming has been recommended by many experts in the world because of its positive ecological impacts such as increasing biodiversity. In Indonesia, the practice of organic farming is very widespread, including in smallholder coffee plantations. This study was intended to determine the impact of the organic farming system applied by smallholder coffee farmers for 2 years on soil arthropod diversity. On the two coffee farmlands, the conventional and organics (1 ha each), 10 plots of 5 x 20 meters were set and in each of these plots 5 sampling points were defined for collecting soil arthropods using pit-fall technique. The analysis of arthropod diversity in the two fields was quantified using the Shannon-Wiener diversity index model. The results showed that the two compared coffee farming systems had the same index of diversity (H ') and evenness (E). However, statistical tests using the Hutcheson t-test revealed that the variance in diversity of arthropods in organic coffee farms was significantly higher than in conventional ones (α <0.001). Therefore, it can be concluded that the practice of organic coffee farming, although in a short time, has been able and potent to increase the population and/or diversity of soil animals.

DIVERSITY AND COMPOSITION OF SOIL ARTHROPODE IN THE REVEGETATION AREA OF COAL MINING USED LAND OF PT. BARA ALAM UTAMA, SITE LAHAT, SOUTH SUMATERA

Coal mining can disrupt the balance of the ecosystem, including the soil environment ecosystem as a habitat for soil arthropods. This study aims to see the soil arthropod family, relative density, diversity, dominance and evenness of soil arthropods in the revegetation area of the ex-mining area of PT. Bara Alam Utama. The re-search was conducted in the revegetation area of the former coal mine area of PT. Bara Alam Utama in Lahat district, South Sumatra. The research area consists of 8 location points, namely natural areas, revegetation areas of age 7,6,5,4,3,2 and 1 year. The study was conducted using an exploratory survey method, sampling was car-ried out based on the purposive sampling method by drawing a 100 m long transect with 5 sample plots inside measuring 20 x 10 m at each revegetation age. The results showed that the highest soil arthropod diversity index was found at the 3 year old revegetation location (H = 0.915) and the highest soil arthropod evenness index was at the 3 year old revegetation location (e = 0.17), while the highest soil arthropod dominance index was at 5 year old revegetation location (D = 0.886) which causes the 5 year revegetation location to have the lowest soil ar-thropod diversity index and evenness index (H = 0.351 and e = 0.054), while the lowest soil arthropod domi-nance index value is at the 3 year old revegetation location (D = 0.667), so it can be seen that there is a correla-tion between the diversity index and the evenness index of soil arthropods where both are inversely proportional to the results of the calculation of the dominance index. The high and low diversity index at each research loca-tion is influenced by abiotic factors (pH, soil temperature and soil moisture), age of revegetation and type of vegetation