Soil Compaction after Increasing the Number of Wheeled Tractors Passes on Forest Soils in West Carpathians

Soil disturbance and compaction are inherent in ground-based harvesting operations. These changes are affected by numerous factors, related mainly to the technical parameters of the machines, soil conditions, and the technology used. This study aimed to analyze the changes of surface layers of soil caused by skidder traffic without loads on the Cambisols of Western Carpathians. We observed changes in the soil bulk density and penetration resistance. The results showed that only machine traffic caused a 0.32 to 0.35 (g cm−3) increase in soil bulk density. Besides machine traffic, bulk density was affected by soil moisture content. Penetration resistance of soil increased by 0.15 to 1.04 (MPa) after traffic of 40 machines. Penetration resistance showed a lower increase after traffic, and regression and correlation analysis proved a relationship between penetration resistance, skeleton content, and penetration depth, besides the number of machine passes (r = 0.33–0.55). Observing the changes in the physical properties of soils caused by machine traffic allows for a more detailed view of the effects of forest harvesting machinery on forest soils.

The role of row crop predecessors in controlling weediness and increasing the productivity of rapeseed and rapeseed seeds

Practice shows that the demand for oilseeds is currently very high. Having the potential of large processing capacities in the southern part of the Non-Black Earth Zone of Russia, oilseeds are in high demand, characterizing rapeseed and rape as high-margin crops in agricultural production. The study of the influence of row crop predecessors on the productivity of cruciferous oilseeds in the conditions of this region is interesting and relevant, which served to determine the direction of research. The article presents data on determining the effectiveness of predecessors on weediness, growth and development, productivity of agrocenoses of rapeseed and rape of spring forms. On the dark gray forest soils of the Ryazan region, the maximum yield of oilseeds of rape and rape was obtained on the variants where the predecessor potato was chosen (2.80 t / ha for rape, 2.68 t / ha for rape), the minimum yield of rape and rape was obtained from the predecessor of corn for grain (2.55; 2.44 t / ha, respectively). A direct dependence of the weediness of crops to the yield of oilseeds of the studied crops was revealed. Keywords: RAPESEED, MUGGY, PREDECESSORS, CLOGGING, YIELD, QUALITY

Phosphorus fluxes in two contrasting forest soils along preferential pathways after experimental N and P additions

The assessment of impacts of an altered nutrient availability, e.g. as caused by consistently high atmospheric nitrogen (N) deposition, on ecosystem phosphorus (P) nutrition requires understanding of P fluxes. However, the P translocation in forest soils is not well understood and soil P fluxes based on actual measurements are rarely available. Therefore, the aims of this study were to (1) examine the effects of experimental N, P, and P+N additions on P fluxes via preferential flow as dominant transport pathway (PFPs) for P transport in forest soils; and (2) determine whether these effects varied with sites of contrasting P status (loamy high P/sandy low P). During artificial rainfall experiments, we quantified the P fluxes in three soil depths and statistically analyzed effects by application of linear mixed effects modeling. Our results show that the magnitude of P fluxes is highly variable: In some cases, water and consequently P has not reached the collection depth. By contrast, in soils with a well-developed connection of PFPs throughout the profile fluxes up to 4.5 mg P m−2 per experiment (within 8 h, no P addition) were observed. The results furthermore support the assumption that the contrasting P nutrition strategies strongly affected P fluxes, while also the response to N and P addition markedly differed between the sites. As a consequence, the main factors determining P translocation in forest soils under altered nutrient availability are the spatio-temporal patterns of PFPs through soil columns in combination with the P nutrition strategy of the ecosystem.

Forest Soils—What’s Their Peculiarity?

Mankind expects from forests and forest soils benefits like pure drinking water, space for recreation, habitats for nature-near biocenoses and the production of timber as unrivaled climate-friendly raw material. An overview over 208 recent articles revealed that ecosystem services are actually the main focus in the perception of forest soil functions. Studies on structures and processes that are the basis of forest soil functions and ecosystem services are widely lacking. Therefore, additional literature was included dealing with the distinct soil structure and high porosity and pore continuity of forest soils, as well as with their high biological activity and chemical soil reaction. Thus, the highly differentiated, hierarchical soil structure in combination with the ion exchange capacity and the acid buffering capacity could be described as the main characteristics of forest soils confounding the desired ecosystem services. However, some of these functions of forest soils are endangered under the influence of environmental change or even because of forest management, like mono-cultures or soil compaction through forest machines. In the face of the high vulnerability of forest soils and increased threads, e.g., through soil acidification, it is evident that active soil management strategies must be implemented with the aim to counteract the loss of soil functions or to recover them.

DNA Metabarcoding Reveals Cryptic Geographically-influenced Microbial Diversity After Anthropogenic Impact in Original Forest Soils on the Isolated Trindade Island, South Atlantic

Located 1,140 km from the South American coastline in the South Atlantic Ocean, and with an age of 4 million years, Trindade Island is the most recent volcanic component of Brazilian territory. Its vegetation was severely damaged by human influence in particular through the introduction of exotic grazing animals such as goats. However, since the complete eradication of goats and other feral animals in the late 1990s, the island’s vegetation has been recovering and even some endemic species that had been considered extinct have been rediscovered. In this study we set out to characterize the contemporary microbial diversity of Trindade Island forest soils using metabarcoding by High Throughput Sequencing (HTS). Sequences of representative of two domains (Bacteria and Archaea) and five kingdoms (Fungi, Metazoa, Protozoa, Chromista and Viridiplantae) were identified. Bacteria were represented by 20 phyla and 116 taxa, while and Archaea by only one taxon. Fungi were represented by seven phyla and 250 taxa, Viridiplantae by five phyla and six taxa, Protozoa by five phyla and six taxa, Metazoa by three phyla and four taxa and Chromista by two phyla and two taxa. Even after the considerable anthropogenic impacts and devastation of the island’s natural forest, our sequence data revealed the presence of a rich, diverse and complex diversity of microorganisms, invertebrates and plants.

Agroecological land typification

The minimum required information and the sequence of agroecological land type allocation on the land management territory of the experimental station (ES) located in the forest-steppe of the Priob'ye region of Novosibirsk is described. Two agroecological land types are distinguished: the first type (upland lands) is represented by leached chernozem in combination with common, podzolized and dark-grey forest soils; the second type (slightly erosive lands) is represented by leached chernozem in combination with dark-grey forest soils. Soil cover of ES in both types of lands is represented by leached chernozem (Lch-2-2s), the share of which for the first type is 75.26%, for the second - 76.26% of the total area of the types. The first agroecological land type is characterized by a range of heights from 134 to 165 m. The working areas are located on the slopes between 0 and 3 degrees in relation to the terrain angle. Vertical dissection of the relief averages 1.3 m, horizontal dissection by erosion forms is 0.8 km/km2. The second type of land is characterized by an elevation of 113 to 137 meters above sea level and a slope of 1 to 4 degrees. Vertical dissection of the terrain averages 1.7 m, horizontal dissection by erosion forms 0.9 km/km2. Typification was carried out with the help of a generated Digital Land Use Model (DLM) of the ES based on the analysis of geographical information, remote sensing materials (ERS) and cadastral map. The DLM consists of the following geo-information layers: topography, land cover, digital elevation model (DEM), working areas. The DEM includes information on slope steepness and exposure, vertical and horizontal dissection.

Effects of Soil Quality on the Microbial Community Structure of Poorly Evolved Mediterranean Soils

Physical and chemical alterations may affect the microbiota of soils as much as the specific presence of toxic pollutants. The relationship between the microbial diversity patterns and the soil quality in a Mediterranean context is studied here to test the hypothesis that soil microbiota is strongly affected by the level of anthropogenic soil alteration. Our aim has been to determine the potential effect of organic matter loss and associated changes in soil microbiota of poorly evolved Mediterranean soils (Leptosols and Regosols) suffering anthropogenic stress (i.e., cropping and deforestation). The studied soils correspond to nine different sites which differed in some features, such as the parent material, vegetation cover, or soil use and types. A methodological approach has been used that combines the classical physical and chemical study of soils with molecular characterization of the microbial assemblages using specific primers for Bacteria, Archaea and ectomycorrhizal Fungi. In agreement with previous studies within the region, physical, chemical and biological characteristics of soils varied notably depending on these factors. Microbial biomass, soil organic matter, and moisture, decreased in soils as deforestation increased, even in those partially degraded to substitution shrubland. Major differences were observed in the microbial community structure between the mollic and rendzic Leptosols found in forest soils, and the skeletic and dolomitic Leptosols in substitute shrublands, as well as with the skeletic and dolomitic Leptosols and calcaric Regosols in dry croplands. Forest soils displayed a higher microbial richness (OTU’s number) and biomass, as well as more stable and connected ecological networks. Here, we point out how human activities such as agriculture and other effects of deforestation led to changes in soil properties, thus affecting its quality driving changes in their microbial diversity and biomass patterns. Our findings demonstrate the potential risk that the replacement of forest areas may have in the conservation of the soil’s microbiota pool, both active and passive, which are basic for the maintenance of biogeochemical processes.