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This study explored whether wildfire alters the soil properties and arbuscular mycorrhizal fungi (AMF) community composition when compared with burnt rangeland, non-burnt rangeland and adjacent tilled in mesothermal ecosystems. The study was carried out in August 2020, 1 year later after wildfire. The results of this study showed that the wildfire played a key role in altering soil characteristics and AMF community composition in Bartin Province located in the Western Black Sea Region. Soil samples were made according to standard methods. AMF spores were isolated according to the wet sieving method, and the spores of AMF were identified according to their morphological characteristics. Analysis of variance was performed to determine the differences between the parameters, and correlation analysis was performed to determine the relationships between the parameters. The highest values of soil organic carbon (2.20%), total nitrogen (0.18%), K2O (74.68 kg/da), root colonization (87.5%) and the frequency of occurrence of Funneliformis geosporum (20%), Claroideoglomus claroideum (16%) and Claroideoglomus etunicatum (11%) were found in burnt rangeland. Sporulation of Acaulospora dilatata, Acaulospora morrowiae, Acaulospora tuberculata, Scutellospora castanea, Scutellospora coralloidea, Scutellospora scutata, Glomus coremioides and Glomus multicaule was either decreased or completely inhibited in the burnt rangeland. While species diversity of AMF (12) decreased, the number of AMF spores (325.6 (number/50 gr soil)) increased in burnt areas. In conclusion, the number of spores and root colonization of AMF increased but species diversity of AMF reduced after the wildfire. In ecosystems with high fire risk where AMF transfer is planned, it is suggested that it would be more appropriate to select species with an increase in spore number after fire. [ABSTRACT FROM AUTHOR]

The soil physical-chemical changes in different land uses in a Tropical Cambisol at Apodi Plateau, Northeastern Brazil, were investigated between May 2017 and April 2018. Soil samples were collected at three soil layers (0–5, 5–15, and 15–25 cm) under three land uses: a 6-year agroecological farming system, a 10-year fruticulture farming system, and a 6-year conventional farming system. We evaluated: bulk density, soil porosity, weighted average diameter (WAD), geometric mean diameter (GMD), soil pH, soil organic carbon (SOC), P, and sum of bases. Soil quality index was built by considering four main functions: Water supply and storage, root growth capacity, nutrient cycling, and soil conservation. Our results emphasized the land use influence on the soil physical-chemical traits in a Tropical Cambisol. The PCA analyses showed that SOC, soil porosity, bulk density, WAD, GMD, soil pH, sum of bases, and soil P content were the main factors contributing to the data variance. We found the highest values of soil quality index in the conventional farming system (0.57 ± 0.03). The results highlight the importance to consider land uses that increase the sum of bases, WAD, GMD, and SOC content, and decrease bulk density. Our findings suggest that (1) a conventional farming system with liming and fertilizers' input positively changed soil physical-chemical traits, which in turn improved soil quality in a tropical Cambisol; and (2) by altering soil functions land uses may create a sustainable cycle into the soil profile thus promoting soil quality. [ABSTRACT FROM AUTHOR]

Fruticulture in the Amazonian Rainforest is one of the main causes of deforestation, biodiversity loss, and soil erosion. Fruticulture plays a key role in the soil traits and soil organic matter (SOM) compartments by altering the soil ecosystem. Our aim was to assess the influence of Forest–Fruticulture conversion on soil traits, and SOM fractions in Brazil's Legal Amazon. The experiment was carried out in field conditions using four land uses as main treatments: Bixa orellana, Theobroma grandiflorum, Paullinia cupana, and the Amazon Rainforest. The soil physicochemical traits were analyzed using samples that were collected from 0–5, 5–10, and 10–20 cm soil depth by using grids (10 × 10 m) with 36 sampling points. Our results showed that the Fruticulture promoted an increase in bulk density, GMD, aggregate diameter, soil porosity, gravimetric moisture, sand, clay, carbon associated with humic acid, and, the sum of bases (K+, Ca2+, and Mg2+), while the Amazon Rainforest showed the highest values of silt, soil P content, SOC, p-SOC, m-SOC, carbon associated with fulvic acid, humine, and soil C stock. Overall, the fruticulture farming systems have negative effects on SOM compartments. The results of our study highlight the importance of considering fruticulture with endemic plant species by promoting soil fertility and soil aggregation. [ABSTRACT FROM AUTHOR]

The role of soil biotic and abiotic factors in crucial soil functions such as primary production, organic matter dynamics, nutrient cycling, and soil biota community structure in the Araucaria ecosystem remains poorly quantified. We aimed to understand how the development of organic horizons, root growth, soil chemical properties, and the entire soil biota community affected the soil quality in even aged and monospecific Araucaria angustifolia plantations. We collected soil monoliths to describe layers of organic matter and the complex soil food web into these layers. We determined soil pH, soil moisture, total nitrogen, available P, and total organic carbon into each layer (litter, F-layer, H-layer, and A horizon), the biomass of fine roots, the community structure of soil biota, arbuscular mycorrhizal fungi, and nematodes, as well as the microbial biomass carbon. In the high-quality site, there was significantly higher organic matter formation, nutrient cycling (N and P), root growth, soil moisture, soil biota diversity, arbuscular mycorrhizal fungi, and nematodes evaluated by the microbial biomass carbon compared to the low-quality site. High-quality sites promote the development of organic horizons, root growth on superficial layers that provide plant nutrient release, the A horizon nutrient contents, and the entire soil biota community in monospecific Araucaria angustifolia plantations located on humid subtropical Cambisols. This creates a positive plant-soil feedback that maintains soil quality and increases primary production, nutrient cycling, and habitat and food for the soil food web. [ABSTRACT FROM AUTHOR]

We aimed to analyse the effects of Cryptostegia madagascariensis' invasion on soil biota community composition from a tropical Fluvisol at the Brazilian Northeast. We collected soil organisms from two dissimilar environments (e.g., invaded and non-invaded) using Provid-type traps into transects. There was a positive correlation between the abundance of Araneae, Blattodea, Homoptera and, Pseudoscorpiones with the invaded environment. On the other hand, the frequency of occurrence of Hymenoptera was significantly higher in the invaded environment compared to the non-invaded one. The biological invasion process promoted by C. madagascariensis reduces soil biota diversity, and the frequency of occurrence of important functional groups, such as predators (e.g., Araneae, Dermaptera, and Scorpiones), and litter transformers (e.g., Coleoptera). This creates a negative plant-soil feedback that promote the functional redundancy process by soil organisms and the biological invasion process by the invader into the Caatinga ecoregion. [ABSTRACT FROM AUTHOR]

Soil macroarthropods are organisms considered as key factors to sustain soil quality and sustainability due to their services to soil ecosystem. The community structure and seasonal variation of soil macroarthropods in 5-year cultivation of green manure plant species in the Brazilian semi-arid, Areia, Paraiba, Brazil were investigated between June and December 2018. Soil samples and macroarthropod specimens were collected using soil cores and Provid-type traps, respectively, during rainy and dry seasons. We characterized both soil chemical properties and macroarthropod community under ten green manure plant species: Brachiaria decumbens Stapf. cv. Basilisk, Canavalia ensiformis (L.) DC, Crotalaria juncea L., Crotalaria ochroleuca G. Don, Crotalaria spectabilis Roth, Lablab purpureus (L.) Sweet, Mucuna pruriens (L.) DC., Neonotonia wightii (Wight & Arn.) J.A. Lackey, Pennisetum glaucum L., and Stilozobium aterrimum Piper & Tracy. The highest values of richness, diversity and dominance in the macroarthropod community during the rainy season were found on the plots where C. spectabilis and M. pruriens were cultivated, whereas during the dry season the highest values were found in the plots where C. ochroleuca, C. spectabilis, and S. aterrimum were cultivated. In the plots where B. decumbens and P. glaucum where cultivated, we found lower values of richness, diversity, and dominance in the macroarthropod community compared to the leguminous plant species during rainy and dry seasons. Our findings suggest that: 1) green manure practice and seasonality changed soil macroarthropod community, trophic structure, and ecological processes in semi-arid conditions; and 2) abundance of predators, ecosystem engineers, decomposers and herbivores was promoted by plant species from Fabaceae family. The results highlight the importance to consider plant species from Fabaceae family as habitat and food resources for soil fauna community. [ABSTRACT FROM AUTHOR]

Deforestation in the Amazonian rainforest is the main cause of biodiversity loss, soil erosion, and climate change. Land covers influence the soil properties, soil biota community composition, and litter properties by providing habitat and nutrients. Our aim here was to present a quantitative analysis of the soil biochemical properties, soil biota assemblage, and litter properties associated with four land covers (primary Amazon rainforest, pasture, Hevea brasiliensis , and deforested sites) from the Brazil's Legal Amazon, Rio Branco, Acre. The non-metric multidimensional scaling (NMDS) grouped the land covers in four groups considering the dissimilarities on soil biota abundance between each other. The SEM models showed that deforestation increased the soil pH, and decreased SOC, TN, P, microbial N biomass, microbial C biomass, litter lignin content, litter N, C and P contents, and biodiversity indices (Margalef index, and α diversity). The results of our study highlighted the importance of considering land covers in Brazil's Legal Amazon, based on a sustainable way to improve soil quality and soil biodiversity, since even the studied monocropping system (pasture) showed decreases in habitat provision (litter deposition) and nutrient availability. Thus, the use of forest systems (H. brasiliensis) or the preservation of primary Amazon rainforest may positively influence the soil chemical properties, soil biota, and litter properties. • Deforestation increased soil pH, but decreased SOC, N, P, microbial biomass, and respiration. • Deforestation reduced the diversity indices, and uniformity index. • Litter deposition and quality were strongly related to soil biota abundance and diversity. • Pasture increased N and microbial respiration, while decreased all biodiversity indices. • Hevea brasiliensis increased Simpson's diversity index and litter C content. [ABSTRACT FROM AUTHOR]

Vitis vinifera is a common plant species cultivated in Southern Brazil for vine production. Although this plant species is commonly found near the Mixed Ombrophilous Forest, the V. vinifera plantation is cultivated in areas for a long-term thus changing the soil ecosystem and functional diversity. We aimed to compare the soil chemical properties, soil biota assemblage, litter traits, decay rate and priming effect in the two adjacent environments (e.g., grape vine plantation vs. natural ecosystem). Soil chemical properties, soil biota community composition, and litter traits of V. vinifera plantation were compared with an adjacent natural ecosystem (e.g., Mixed Ombrophilous Forest) from September 2019 to June 2021. Litter decay rate and priming effect was estimated by using native tree residues on litter bags in both studied environments. We also assessed the influence of soil biota on decay rate through a litterbag assay. Our results showed that both studied environments differed in soil chemical properties and soil biota community composition. However, in the V. vinifera plantation litter decay rate, and priming effect were higher, due to the presence and activities of soil organisms from Collembola - Paronellidae. Thermal amplitude, litter quality, and soil organisms' activity were the main factors contributing to the data variance. Both native tree residues, A. angustifolia and D. sellowiana , showed the highest decay rate and priming effect in the V. vinifera plantation. Our work increases the understanding of the soil food web and ecological processes (litter deposition and nutrient cycling) into subtropical ecosystems. The V. vinifera plantation following a monocropping system does not provide resources to create a well-developed soil food web, which overtime creates negative plant-soil feedback when compared to the natural ecosystem. However, our study opens a new perspective for a future agroforestry system using two endangered species from the Brazilian Mixed Ombrophilous Forest seeking for vine production, soil sustainability, and biodiversity conservation. • The high litter k-factor , and priming effect in the vineyard are related to the high abundance of Collembola-Paronellidae. • k and priming effect were increased by adding A. angustifolia , and D. sellowiana residues in the vineyard. • Thermal amplitude, litter N, lignin, and soil organisms were the main factors contributing to the data variance. [ABSTRACT FROM AUTHOR]