Soil Chronosequence Research Articles

Reforestation practices have varied the resilience of nosZ-type denitrifier communities: A 40-year soil chronosequence study

Reforestation practices have varied the resilience of nosZ-type denitrifier communities: A 40-year soil chronosequence study

Substrate Origin Controls Phosphorus Availability in Globally Distributed Long-Term Chronosequences

Phosphorus (P) is one of the most important elements for soil biology and biogeochemistry worldwide. Yet, despite decades of research, important uncertainties persist about the drivers and changes in soil P forms during long-term soil formation. Here, we analyzed topsoils from nine globally distributed retrogressive soil chronosequences aiming to evaluate the relative contribution of key environmental factors (that is, soil age, substrate origin, climate, soil attributes, and vegetation) in explaining the long-term dynamics of primary, occluded, non-occluded, organic, and total P across different terrestrial ecosystems. We found that, rather than soil age, substrate origin was the main driver controlling the fate of different P fractions across contrasting environmental conditions. Moreover, our findings suggest that temporal patterns governing the long-term dynamics of different P forms as soils develop are not consistent among soil chronosequences, which is a result of contrasting environmental conditions, especially substrate origin. We further showed that topsoil total P was the greatest at intermediate soil development stage across the globe. Lastly, our results showed that P fractions were highly correlated with multiple surrogates of ecosystem services, such as carbon sequestration, plant productivity, and biodiversity. Together, our work provides new insights into the natural history of P availability, and further highlights that substrate origin, rather than soil age, is essential to predict changes in P availability in response to physical perturbation and climate change.

Nutrient cycling characteristics along a chronosequence of forest primary succession in the Hailuogou Glacier retreat area, eastern Tibetan Plateau.

The Hailuogou Glacier has been continuously retreating since the end of the Little Ice Age, resulting in a 125-year soil chronosequence and a complete primary forest succession sequence. Nutrient cycling and utilization are the foundation to forest succession processes and dynamic changes, directly influencing the structure and stability of ecosystems. However, our understandings on the characteristics of ecosystem nutrient accumulation and recycling during succession, especially in the context of primary succession within glacier retreat areas, remain limited. To address this, we investigated nutrient characteristics across six forest primary succession sites in the Hailuogou Glacier retreat area. Six sites representing three forest stages: the pioneer plant stage (S1), the broad-leaved forest stage (S2-S4), and the coniferous forest stage (S5-S6). Three quadrats were established at each site, and measurements of biomass as well as soil characteristics were documented within each quadrat. Subsequently, we collected samples of vegetation, soil and litter. By measuring the concentrations of N, P, K, Ca, and Mg in vegetation and soil and combining with the data of the quadrat survey, the pools and nutrient characteristics of N, P, K, Ca, and Mg in various components of the ecosystem were calculated at each site. Our findings indicated that: (1) Nutrient pools, excluding the soil C layer, increased with forest primary succession, reaching 5,995.71 kg hm-2 N, 461.83 kg hm-2 P, 3,798.09 kg hm-2 K, 7,559.81 kg hm-2 Ca and 1,948.13 kg hm-2 Mg at site S6; however, the pools of P, K, and Mg in the Oa layer, and Ca and Mg in the tree layer, attained their peak levels at sites S3 to S4. (2) The pools of N, Ca, and Mg in the organic soil were significantly greater than vegetation. Although over 60% of the P and K were stored in the organic soil at site S1, these proportions shifted, with vegetation holding 60.71% of P and 56.86% of K at site S5. (3) Broad-leaved forests exhibited higher nutrient return, cycling, and absorption, thereby accelerating nutrient circulation and depleting soil nutrients to maintain growth. In contrast, coniferous forests were more efficient at nutrient utilization and storage, retaining nutrients and maintaining high biomass and productivity in nutrient-poor environments. Overall, these findings highlighted that the nutrients in each component of the ecosystem continue to accumulate with forest primary succession. Coniferous forests' nutrient cycling mechanisms offer a competitive edge in nutrient-poor environments, enhancing ecosystem stability.

Podzolization in a 150-year chronosequence of soils under pine timber forest on inland dunes in the Toruń Basin (Northern Poland)

Podzolization in a 150-year chronosequence of soils under pine timber forest on inland dunes in the Toruń Basin (Northern Poland)

Bacterial and fungal diversity, community composition, functional groups, and co-occurrence network succession in dryland and paddy soils along a 3000-year chronosequence

Bacterial and fungal diversity, community composition, functional groups, and co-occurrence network succession in dryland and paddy soils along a 3000-year chronosequence

Synergistic regulation of salinity and nutrients on organic carbon mineralization in a 700-year cultivated saline soil chronosequence

Synergistic regulation of salinity and nutrients on organic carbon mineralization in a 700-year cultivated saline soil chronosequence

Exploring microbial dynamics, metabolic functions and microbes–metabolites correlation in a millennium paddy soil chronosequence using metabolome and microbiome

BackgroundPaddy soil is a typical soil type affected by anthropogenic management and factors related to natural soil formation. The evolution from mudflats to typical paddy soils can significantly affect the soil microecology. Previous studies have reported the evolution of soil physicochemical properties, microbes, and related soil environmental factors in a millennium paddy soil chronosequence. However, the potential biological mechanisms of changes in metabolites and microbes–metabolites interaction are poorly understood. Therefore, a combination of high-throughput sequencing and environmental pseudotargeted metabolomics techniques was adopted to explore the effects of the millennium paddy soil chronosequence on microbial communities, metabolites, and their functions and interactions.ResultsThe soil ecology changed greatly in the first 60 years of the transition from mudflat to paddy planting. Among the microbial communities, the response of the bacteria to the chronosequence was more sensitive than that of fungi. Among them, the bacterial communities of Proteobacteria, Bacteroidetes, Acidobacteria, and Nitrospirae exhibited regular succession over the chronosequence, but the fungal communities did not show regular changes. Bacterial function prediction revealed that the beginning of the critical stage of the evolution from mudflat to paddy soil involved the organic matter cycle and energy flow. In contrast, fungi were characterized mainly by pathogenic and saprophytic functions. The results of the principal component analysis of the metabolites revealed a similar pattern of change as that of the microbes. Seventy-five characteristic metabolites exhibited three trends of change during the development of the paddy soil chronosequence. Twenty-five differentially active metabolic pathways, including glyoxylate and dicarboxylate metabolism, starch and sucrose metabolism, and galactose metabolism, were enriched. In addition, correlation analysis revealed that long-chain fatty acids, short-chain fatty acids, phenolic acids, carbohydrates, and polyalcohols significantly regulate the microbial communities in paddy soil.ConclusionsCombining metabolome and microbiome has expanded the overall understanding of the development of paddy soil under anthropogenic management. During the development of a paddy soil chronosequence, the synergistic regulation of soil physicochemical properties and metabolites in the microbial community results in increased productivity. This study provides a new perspective on microbes and metabolites interaction.Graphical

Aggregate Stability and Aggregate-Associated Organic Matter along a Soil Chronosequence on the Galápagos Archipelago

Aggregate Stability and Aggregate-Associated Organic Matter along a Soil Chronosequence on the Galápagos Archipelago

Fate and potential ecological risk of rare earth elements in 3000-year reclaimed soil chronosequences

The introduction of anthropogenic inputs into natural systems may lead to enduring alterations in the innate characteristics of Rare Earth Elements (REEs). Against this backdrop, the evolutionary processes and environmental drivers of REEs in soil remain uncertain. A 3000-year soil chronosequence with uniform parent material was established in reclaimed farmland along the Yangtze River, reconstructing, for the first time, the dynamic processes of REE accumulation and fractionation over a long-time scale. Analysis of 122 soil samples showed REE concentrations ranging from 146.00 to 216.56μg/g. Based on reclamation duration, three significant stages of REE evolution were identified: natural leaching, rapid accumulation, and stable accumulation with differentiation. Reclaimed soil after 3000 years exhibited a 14.1% increase in REE concentrations compared to fresh sediments, attributed to anthro -pedogenic processes. Moreover, Heavy Rare Earth Elements (HREEs) accumulated faster than Light Rare Earth Elements (LREEs), particularly in deeper soils (60-100cm), where HREE concentrations rose by 34.3%, mainly due to acidic environments promoting HREE fixation. Additionally, the potential ecological risk posed by REEs heightened with reclamation duration, with HREEs exhibiting a sensitivity of 83% to 94%. Our findings stress the urgency of carefully monitoring exogenous REEs introduced through anthropogenic activities, particularly HREEs.

Soil phosphorus fraction and availability dynamics along a 2-million-year soil chronosequence in northern Hainan Island, China

Soil phosphorus fraction and availability dynamics along a 2-million-year soil chronosequence in northern Hainan Island, China

Revegetating Mine Soils with Different Tree Species Influences Molecular Characteristics of Soil Organic Matter

ABSTRACT Although molecular characterization of soil organic carbon is crucial for understanding its dynamics, studies on reclaimed coal mine soil are comparatively limited. Therefore, the primary objective of this study was to ascertain the influence of tree species on the soil organic carbon content and molecular characteristics of soil organic carbon in a chronosequence of reclaimed coal mine soil. To investigate the effects of reclamation time on soil organic carbon characteristics, a chronosequence of three coal mine soil was used, each exhibiting different ages of reclamation: 8, 14, and 25 years. Along a re-vegetation age gradient of 8 to 25 years, the total soil organic carbon content increased. Within the 25 years of restored soil, the FTIR absorption intensities were lowest within the range of 2,920 and 2,850 cm−1, while they were highest within the range of 1,685, 1,425, and 1,285 cm−1which indicates presence of aromatic C=C. This shows that aromatic compounds contributed more significantly to the composition of soil organic carbon compared to aliphatic structures. Based on molecular characteristics, it is suggested that the soil organic carbon in 25-year old revegetated coal mine soil consists of aromatic and recalcitrant carbon. Among three tree species Dalbergia sissoo can be used for reclamation as quality and quantity of carbon found was higher under this tree species. In conclusion, the results indicated that the molecular properties of soil organic carbon were extremely important for understanding the dynamics of soil organic carbon in a restored coal mine soil chronosequence.

Embedded Complexity of Evolutionary Sequences.

Multiple pathways and outcomes are common in evolutionary sequences for biological and other environmental systems due to nonlinear complexity, historical contingency, and disturbances. From any starting point, multiple evolutionary pathways are possible. From an endpoint or observed state, multiple possibilities exist for the sequence of events that created it. However, for any observed historical sequence-e.g., ecological or soil chronosequences, stratigraphic records, or lineages-only one historical sequence actually occurred. Here, a measure of the embedded complexity of historical sequences based on algebraic graph theory is introduced. Sequences are represented as system states S(t), such that S(t - 1) ≠ S(t) ≠ S(t + 1). Each sequence of N states contains nested subgraph sequences of length 2, 3, …, N - 1. The embedded complexity index (which can also be interpreted in terms of embedded information) compares the complexity (based on the spectral radius λ1) of the entire sequence to the cumulative complexity of the constituent subsequences. The spectral radius is closely linked to graph entropy, so the index also reflects information in the sequence. The analysis is also applied to ecological state-and-transition models (STM), which represent observed transitions, along with information on their causes or triggers. As historical sequences are lengthened (by the passage of time and additional transitions or by improved resolutions or new observations of historical changes), the overall complexity asymptotically approaches λ1 = 2, while the embedded complexity increases as N2.6. Four case studies are presented, representing coastal benthic community shifts determined from biostratigraphy, ecological succession on glacial forelands, vegetation community changes in longleaf pine woodlands, and habitat changes in a delta.

Reclamation of coastal wetland to paddy soils alters the role of bacteria and fungi in nitrous oxide emissions: Evidence from a 53-year reclamation chronosequence study

Reclamation of coastal wetland to paddy soils alters the role of bacteria and fungi in nitrous oxide emissions: Evidence from a 53-year reclamation chronosequence study

Microbiota recovery in a chronosquences of impoverished Cerrado soils with biosolids applications

Mining activities put the Brazilian savannas, a global biodiversity hotspot, in danger of species and soil carbon losses. Experiments employing biosolids have been applied to rejuvenate this degraded ecosystem, but a lingering question yet to be answered is whether the microbiota that inhabits these impoverished soils can be recovered towards its initial steady state after vegetation recovery. Here, we selected an 18-year-old restoration chronosequence of biosolids-treated, untreated mining and native soils to investigate the soil microbiota recovery based on composition, phylogeny, and diversity, as well as the potential factors responsible for ecosystem recovery. Our results revealed that the soil microbiota holds a considerable recovery potential in the degraded Cerrado biome. Biosolids application not only improved soil health, but also led to 41.7% recovery of the whole microbial community, featuring significantly higher microbiota diversity and enriched groups (e.g., Firmicutes) that benefit carbon storage compared to untreated mining and native soils. The recovered community showed significant compositional distinctions from the untreated mining or native soils, rather than phylogenetic differences, with physiochemical properties explaining 55% of the overall community changes. This study advances our understanding of soil microbiota dynamics in response to disturbance and restoration by shedding light on its recovery associated with biosolid application in a degraded biodiverse ecosystem.

Evolution and controls of organic phosphorus based on 31P nuclear magnetic resonance spectroscopy along a 2-million-year tropical soil chronosequence in northern Hainan Island, China

Evolution and controls of organic phosphorus based on 31P nuclear magnetic resonance spectroscopy along a 2-million-year tropical soil chronosequence in northern Hainan Island, China

Chemical weathering along a one-million-year soil age gradient on the Galápagos Islands

Chemical weathering along a one-million-year soil age gradient on the Galápagos Islands

Chronosequential changes in soil-related ecosystem services after coastal reclamation: Insights for coastal cropland protection

Chronosequential changes in soil-related ecosystem services after coastal reclamation: Insights for coastal cropland protection

Soil nutrients drive changes in the structure and functions of soil bacterial communities in a restored forest soil chronosequence

Soil nutrients drive changes in the structure and functions of soil bacterial communities in a restored forest soil chronosequence

Changes in Diversity and Abundance of Ammonia-Oxidizing Archaea and Bacteria along a Glacier Retreating Chronosequence in the Tianshan Mountains, China.

Glaciers retreating due to global warming create important new habitats, particularly suitable for studying ecosystem development where nitrogen is a limiting factor. Nitrogen availability mainly results from microbial decomposition and transformation processes, including nitrification. AOA and AOB perform the first and rate-limiting step of nitrification. Investigating the abundance and diversity of AOA and AOB is essential for understanding early ecosystem development. The dynamics of AOA and AOB community structure along a soil chronosequence in Tianshan No. 1 Glacier foreland were analyzed using qPCR and clone library methods. The results consistently showed low quantities of both AOA and AOB throughout the chronosequence. Initially, the copy numbers of AOB were higher than those of AOA, but they decreased in later stages. The AOB community was dominated by "Nitrosospira cluster ME", while the AOA community was dominated by "the soil and sediment 1". Both communities were potentially connected to supra- and subglacial microbial communities during early stages. Correlation analysis revealed a significant positive correlation between the ratios of AOA and AOB with soil ammonium and total nitrogen levels. These results suggest that variations in abundance and diversity of AOA and AOB along the chronosequences were influenced by ammonium availability during glacier retreat.

Soil bacterial succession with different land uses along a millennial chronosequence derived from the Yangtze River flood plain

Wetlands reclamation has been a traditional and effective practice for obtaining new land to alleviate the pressure induced by population growth. However, the evolution of soil-dwelling microorganisms along with reclamation and the potential influence of land-use patterns on them remain unclear. In this study, a soil chronosequence derived from Yangtze River sediments was established, comprising of circa 0, 60, 160, 280, 2000, and 3000years, to examine the succession of soil bacterial communities across different land uses. Our analysis revealed obvious development in soil properties and orderly bacterial succession along reclamation gradients. Over time, reclaimed land suffered from varying degrees of abundance loss and biodiversity simplification, with dryland being the most sensitive to reclamation duration changes, whereas woodland and paddies showed slight reductions. Bacterial communities tended to shift from oligotrophs (K-strategist) to copiotrophs (r-strategist) at the phylum level as reclamation proceeded for all land use types. The relative abundance of certain bacterial functional groups associated with the carbon (C) and nitrogen (N) cycles were significantly increased, including those involved in Aerobic chemoheterotrophy, Chitinolysis, Nitrate reduction, Nitrate respiration, and Ureolysis, while other groups, such as those related to Fermentation, Methylotrophy, Nitrification, and Hydrocarbon degradation, exhibited decreased expression. Notably, prolonged reclamation can also trigger ecological issues in soil, including a continuous increase of predatory/exoparasitic bacteria in dryland and woodland, as well as a significant increase in pathogenic bacteria during the later stages in paddy fields. Overall, our study identified the impact of long-term reclamation on soil bacterial communities and functional groups, providing insight into the development of land-use-oriented ecological protection strategies.