Soil Disturbance Research Articles

Soil carbon emissions and influential factors across various stages of vegetation succession in vegetated concrete

After ecological restoration of high and steep slopes in the project disturbed area, soil properties, soil microorganisms, litter types and root types change with the succession of vegetation cover communities. However, the effects of different vegetation successional stages on soil respiration dynamics remain unclear. To elucidate trends and drivers of soil respiration in the context of vegetation succession, we used spatio-temporal alternative applied research. Vegetated concrete-restored slopes (VC) with predominantly herbaceous (GS), shrub (SS), and arborvitae (AS) vegetation were selected, and naturally restored slopes (NS) were used as control. SRS1000 T soil carbon flux measurement system was used to monitor soil respiration rate. The results showed that soil respiration (RS) and fractions of all four treatments showed a single-peak curve, with peaks concentrated in July and August. During the succession of vegetation from herbaceous to arborvitae on VC slopes, RS showed a decreasing trend, and GS was significantly higher than AS by 45%; Compared to NS, RS was 29.81% and 21.56% higher in GS and SS successional stages, respectively, and 27.51% lower in AS stage. RS was significantly and positively correlated with nitrate nitrogen (NO3–-N) and microbial biomass nitrogen (MBN), both of which are important factors in regulating RS under vegetation succession. A bivariate model of soil temperature and water content explains the variability of Rs better. Overall, RS was higher than NS in the transition stage and lower than NS in the equilibrium stage of the vegetation community on VC slopes, and the RS decreases gradually with the vegetation succession of artificial ecological restoration slopes.

Influence of Conservation Agriculture on Certain Soil Qualities Both Physical and Chemical in Relation to Sustainable Agriculture Practices a Review

Conventional tillage raises the possibility of soil erosion and degrades crucial physical characteristics of the soil, such as soil organic carbon (SOC) reduction. Additionally, ineffective management techniques result in a decrease in soil organic matter, a breakdown of the soil's structure, and more erosion. As a result, crop yields have decreased. Conservation agriculture (CA) is being considered as a potential system having the capability of improving soil quality and providing stable yields. This review's primary goal is to demonstrate how conservation agricultural practices affect certain physical and chemical characteristics of soil in order to support sustainable agriculture. So as to produce production system that are sustainable, conservation agriculture refers to cropping system management approaches that support permanent soil cover, low soil disturbance, and appropriate crop rotation. With the use of conservation agriculture techniques, it is possible to enhance the physical and structural health of the soil (by reducing bulk density and improving soil aggregation), in addition to increase soil water infiltration, decrease water runoff and soil loss, decrease evaporation loss, decrease soil organic carbon, and lower greenhouse gas emissions from agriculture. These factors are crucial for maintaining soil health and sustainable crop production. In general, applying the conservation agriculture concepts of limited tillage, soil cover, and legume integration would promote the development of soil microorganisms and organic matter by decreasing erosion. Conservation agriculture is therefore regarded as one of the agricultural systems that have the ability to favorably contribute to soil physical and chemical improvement as well as techniques for mitigating and adapting to climate change.

Composition of soil mesofauna in changing cropping systems due to urbanization in Bengaluru, India.

The study focused on the composition of soil mesofauna within changing cropping systems influenced by urbanization in Bengaluru, Karnataka, India during the rabi season of 2020 (October)-2021 (February). Four major cropping systems, namely pulses (red gram), vegetables (tomato and ridge gourd), horticulture (grapes and chickoo), and agriculture + horticulture crops, (coconut + fodder plantation), were examined across urban, peri-urban, and rural zones in Bengaluru. The research uncovered a total of 714 individuals belonging to 16 different soil mesofauna taxa among the crops studied. Collembolans were found to be the most abundant members of the mesofauna community, with mites following closely. In terms of population dynamics, the highest mesofauna population was observed in December 2020, totaling 248 individuals, while the lowest count was recorded in February 2021, with 104 individuals. Among the crops studied, the highest number of individuals was found in Horticulture systems, with 277 individuals, closely followed by the Agri + horticulture cropping system, which had 158 individuals. When considering the geographical zones, the highest number of individuals was recorded in the urban zones, with 270 individuals, followed by peri-urban areas with 229 individuals, and the rural zone had the lowest count, totaling 225 individuals. From the results, less disturbed soil environment in horticulture cropping system, post-monsoon conditions in December (2020), and the urban heat in urban zone appeared to favor the proliferation of soil mesofauna.

Seedling recruitment in response to stand composition, interannual climate variability, and soil disturbance in the boreal mixed woods of Canada

AbstractAimSeedling recruitment is a vital process for forest regeneration and is influenced by various factors such as stand composition, climate, and soil disturbance. We conducted a long‐term field experiment (18 years) to study the effects of these factors and their interactions on seedling recruitment.LocationOur study focused on five main species in boreal mixed woods of eastern Canada: trembling aspen (Populus tremuloides), paper birch (Betula papyrifera), white spruce (Picea glauca), balsam fir (Abies balsamea), and white cedar (Thuja occidentalis).MethodsSixteen 1‐m2 seedling monitoring subplots were set up in each of seven stands originating from different wildfires (fire years ranging from 1760 to 1944), with a soil scarification treatment applied to every other subplot. Annual new seedling counts were related to growing‐season climate (mean temperature, growing degree days and drought code), scarification, and stand effects via a Bayesian generalized linear mixed model.ResultsSoil scarification had a large positive effect on seedling recruitment for three species (aspen, birch and spruce). As expected, high mean temperatures during the seed production period (two years prior to seedling emergence) increased seedling recruitment for all species but aspen. Contrary to other studies, we did not find a positive effect of dry conditions during the seed production period. Furthermore, high values of growing degree days suppressed conifer seedling recruitment. Except for white cedar, basal area was weakly correlated with seedling abundance, suggesting a small number of reproductive individuals is sufficient to saturate seedling recruitment.ConclusionOur findings underscore the importance of considering multiple factors, such as soil disturbance, climate, and stand composition, as well as their effects on different life stages when developing effective forest management strategies to promote regeneration in boreal mixed‐wood ecosystems.

Soil disturbance caused by timber harvesting in a natural forest, West Sumatera Indonesia

Logging operations in natural forests generally use bulldozers. Bulldozers skid logs from the stump site to the landing site. The bulldozer maneuvers in the felling area cause skid trails and soil compaction. Soil compaction is one of the negative impacts of logging operations. The research aim is to analyze the level of soil compaction in various bulldozer skidding intensities after logging operations. The research occurred at a natural forest area in Siberut West Sumatera, Indonesia. The results of the study showed that there was a relationship between skidding intensity and the level of soil bulk density. The more a bulldozer moves at the same skid trail, the higher the soil bulk density. The range of soil bulk density is from 0.82 g cm−3 to 1.31 g cm−3. The bulk density increases markedly after the bulldozer’s first, second, and third passes. After the fourth pass, the bulk density is relatively constant. The porosity of the soil decreases with the increase of the bulk density. On skid trails where the soil is very compact, seeds that fall on skid trails will have difficulty growing well. Requires planting on primary skid trails. Soil damage in the form of soil compaction by bulldozers needs serious attention in the Reduce Impact Logging technique.

Microbial-explicit processes and refined perennial plant traits improve modeled ecosystem carbon dynamics

Globally, soils hold approximately half of ecosystem carbon and can serve as a source or sink depending on climate, vegetation, management, and disturbance regimes. Understanding how soil carbon dynamics are influenced by these factors is essential to evaluate proposed natural climate solutions and policy regarding net ecosystem carbon balance. Soil microbes play a key role in both carbon fluxes and stabilization. However, biogeochemical models often do not specifically address microbial-explicit processes. Here, we incorporated microbial-explicit processes into the DayCent biogeochemical model to better represent large perennial grasses and mechanisms of soil carbon formation and stabilization. We also take advantage of recent model improvements to better represent perennial grass structural complexity and life-history traits. Specifically, this study focuses on: 1) a plant sub-model that represents perennial phenology and more refined plant chemistry with downstream implications for soil organic matter (SOM) cycling though litter inputs, 2) live and dead soil microbe pools that influence routing of carbon to physically protected and unprotected pools, 3) Michaelis-Menten kinetics rather than first-order kinetics in the soil decomposition calculations, and 4) feedbacks between decomposition and live microbial pools. We evaluated the performance of the plant sub-model and two SOM cycling sub-models, Michaelis-Menten (MM) and first-order (FO), using observations of net ecosystem production, ecosystem respiration, soil respiration, microbial biomass, and soil carbon from long-term bioenergy research plots in the mid-western United States. The MM sub-model represented seasonal dynamics of soil carbon fluxes better than the FO sub-model which consistently overestimated winter soil respiration. While both SOM sub-models were similarly calibrated to total, physically protected, and physically unprotected soil carbon measurements, the models differed in future soil carbon response to disturbance and climate, most notably in the protected pools. Adding microbial-explicit mechanisms of soil processes to ecosystem models will improve model predictions of ecosystem carbon balances but more data and research are necessary to validate disturbance and climate change responses and soil pool allocation.

Influence of foundation pit excavation on the internal force of adjacent shield segment structure

As subway line density increases, excavation of foundation pits around tunnels unavoidably triggers soil disturbance. This consequently alters the on-site strain and distortion fields of the soil, resulting in internal force modifications in the tunnel shield segment and joint failure. To maintain tunnelling structure safety through numerous foundation pit diggings, this study uses a real-world project as its model. Leveraging the tunnel convergent deformation results derived from prior analyses with PLAXIS 3D software, the Midas GTS software is utilized to explore the alterations in internal forces and joint failure patterns of the tunnel subjected to convergent deformations of 4cm and 5cm. The findings are as follows: (i) Under the effect of a vertical load, the segment deformation takes on a transverse elliptical shape. (ii) The majority of joint failure is primarily focused around the foundation pit excavation area, where the base of the arch opens inwardly, and the midsection of the arch expands outwardly. (iii) The stress on the structure escalates as the extent of foundation pit excavation increases.

Identifying the best tillage system to maintain soil properties and crop yields after Conservation Reserve Program grassland conversion

The Conservation Reserve Program (CRP) is a United.States of Americae government program that provides financial incentives to transition marginal croplands to permanent grass cover to conserve soil and water. Few studies have evaluated the best tillage system that maintains soil properties when converting CRP back to cropland. Our objective was to determine how converting CRP to cropland under different tillage practices after three years affects soil C (carbon) stocks, physical and chemical properties, and winter wheat (Triticum aestivium L.) and corn (Zea mays L.) grain yields after 4 yr. We also reviewed literature on the topic to compare previous results against our findings. This experiment was conducted in Sidney, NE, USA on CRP that was converted to production farmland through four tillage practices no-till (NT), disk-sweep (DS), plow-sweep (PS) and deep plow-sweep (DPS) in 2017 and planted to a wheat-corn-fallow rotation. Organic C stock was reduced by 6% in PS and 15% in DPS compared to CRP in the 0–10 cm depth but not in the 0–60 cm. Tillage practice did not affect grain yields in our study but had inconsistent effects according to previous literature. In the upper 10 cm, wet aggregate stability was reduced by 41% in DS, 51% in PS, and 58% in DPS, dry aggregate stability was reduced by 66% in NT, 71% in DS, 74% in PS and 77% in DPS, and plant available water was reduced by 45% in NT, 50% in DS, 39% in PS and 43% in DPS treatment relative to CRP. However, treatments had no effect on cumulative infiltration rate and bulk density. The use of DS or NT when converting CRP to cropland caused the least negative impacts on soil properties when CRP was converted to cropland in our study and in previous studies reported in the literature. Minimizing soil disturbance by reduced or no tillage maintained relevant soil properties 3 yr after CRP conversion to cropland.

Spatial distribution characteristics and influencing factors of shallow and deep soil moisture under ecological restoration in the loess plateau, China

AbstractDeep soil moisture is one of the primary factors restricting vegetation growth on the Loess Plateau (LP) of China. Investigating the spatial variations and influencing factors of shallow and deep soil moisture is of great significance for ecological restoration on the LP. In this study, we sampled disturbed soil up to a depth of 10 m with a soil drill. A 200 × 200 m grid was superimposed on a digital topographic map, and 78 sampling sites were selected across the Zhifanggou (ZFG) watershed. According to the results, the vertical profile of soil could be subdivided into four layers: the shallow active layer (SAL; 0–0.5 m), the shallow rainfall recharge layer (SRL; 0.5–2.2 m), the deep excessive layer (DEL; 2.2–4 m), and the deep stable layer (DSL; 4–10 m). The horizontal distribution characteristics of soil moisture in various soil layers were similar, with a generally high concentration in the south and a low concentration in the north. In addition, a relatively low soil moisture content (SMC) occurred in the center of the SRL. Soil moisture was negatively correlated with slope and slope aspect between 0 and 2.2 m (p < 0.05), whereas slope and slope aspect had no significant effects on deep soil moisture (>2.2 m). The SMCs of the four soil layers, from lowest to highest, were as follows: forestland, shrubland, and grassland. The SMC of forestland was negatively correlated with restoration age, whereas the SMC of grassland was positively correlated with restoration age. This study deepens our understanding of shallow and deep soil moisture distribution characteristics and the corresponding ecological restoration on the LP and provides a reference for the rational use of deep soil moisture.

The normalized difference vegetation index value of volcanic paddy soils of Mt. Talang using Landsat 8 image

Abstract Accurate and up-to date information on the spatial distribution of paddy fields in volcanic soils is important. The volcanic soil in West Sumatra covers an area about 602.500 ha. Soils of volcanic origin are considered fertile and productive soils. They are widely used to grow annual and perennial crops. Paddy cultivation in volcanic soils is commonly practiced in West Sumatra. Remote sensing data can be used to observe the condition of rice plants in volcanic soils from by calculating the vegetation index value through the NDVI (Normalized Difference Vegetation Index). This study aims to determine the vegetation index of paddy grows in Mt. Talang by using Landsat 8 satellite imagery and correlate the index value with the total carbon and fractions content. Soil samples were collected using the 1x1 km interval grid method from 5099,78 ha of volcanic paddy fields. Soil samples were collected undisturbed and disturbed condition. The undisturbed soil samples were used to analyze bulk density (BD). The disturbed soil samples were dried and sieved with a 2-mm sieve and then analyzed for soil pH (H20 and KCl), Organic C, Labile C, and Very Labile C. All of soil samples have low bulk density (0.76-0.89 Mg/m3). Soil pH is considered neutral (6.50 to 6.93). The average vegetation index value was high, with a maximum value of 0.60 and a minimum value of 0.39. The results of the regression analysis showed that there was no relationship between NDVI and soil chemical properties. Determination of the vegetation index during the growing period of paddy is very useful to improve the accuracy of paddy identification sites at the regional scale and to predict the potential paddy production in due time.

A numerical investigation on the effect of rotation on the cone penetration test

The cone penetration test (CPT) is one of the most popular in situ soil characterization tools. However, the test is often difficult to conduct in soils with high penetration resistance. To resolve the problem, a rotary CPT device has recently been adopted in practice by rotating the rod to increase the penetrability, particularly in deep dense sand. This study investigates the underlying mechanism of the rotation effects from a micromechanical perspective using models based on the discrete element method. With rotation, the cone penetration resistance ( qc) decreases by up to 50%, while the cone torque resistance ( tc) increases gradually. These results are also used to successfully assess existing theoretical solutions. The mechanical work required during penetration is observed to keep rising as the rotational velocity increases. Microscopic variables including particle displacement and velocity field show that rotation reduces the volume of disturbed soil during penetration and drives particles to rotate horizontally, while contact force chain and contact fabric indicate that rotation increases the number of radial and tangential contacts and the corresponding contact forces, forming a lateral stable structure around the shaft, which can reduce the force transmitted to the particles below the cone, thus decreasing the vertical penetration resistance.

Soil heavy metal pollution and ecological risk assessment in disturbed and undisturbed soil of Morigaon, Assam

Soil heavy metal pollution and ecological risk assessment in disturbed and undisturbed soil of Morigaon, Assam

Installation Disturbance of Helical Anchor in Dense Sand and the Effect on Uplift Capacity Based on Discrete Element Method

Helical anchors have been extensively employed as foundation systems for carrying tension loads due to their installation efficiency and large uplift capacity. However, the installation influences of helical anchors are still not well understood, especially for multi-helical anchors. The matrix discrete element method was used to model the process of helical anchor penetration and pull-out in dense sand to investigate the effects of the anchor geometry and advancement ratio (AR, the relative vertical movement per rotation) on soil disturbance, the particle flow mechanism, and the uplift capacity. For shallow helical anchors, the overall disturbance zone is the shape of an inverted cone after installation, while for deep helical anchors, it is funnel-shaped. The advancement ratio has significant effects on the soil particle movement and uplift capacity of helical anchors. The soil particle flow mechanism around helical plates has been identified for single-helix anchors at various advancement ratios, and for double-helix anchors, the influence of the top plate on particle movement during installation was investigated. The uplift capacities of both single- and double-helix anchors increase with the decrease in the AR (AR = 0.5~1), and the influence decreases with the anchor embedment ratio. The efficiency of double-helix anchors induced by installation is close to 1 at pitch-matched installation (AR = 1), indicating that the impact of the top plate during installation is minimal in this case.

Seed traits and recruitment interact with habitats to generate patterns of local adaptation in a perennial grass.

A fundamental challenge in the field of ecology involves understanding the adaptive traits and life history stages regulating the population dynamics of species across diverse habitats. Seed traits and early seedling vigor are thought to be key functional traits in plants, with important consequences for recruitment, establishment, and population persistence. However, little is known about how diverse seed traits interact with seed and microsite availability to impact plant populations. Here, we performed a factorial experiment involving seed addition and surface soil disturbance to explore the combined effects of seed and site availability using genotypes characterized by varying seed mass and dormancy traits. Additionally, we included hybrids that exhibited recombined seed trait relationships compared with natural genotypes, allowing us to assess the impact of specific seed traits on establishment across different sites. We detected a significant three-way interaction between seed addition, site conditions, and soil surface disturbance, influencing both seedling establishment and adult recruitment in Panicum hallii, a perennial grass found in coastal mesic (lowland) and inland xeric (upland) habitats. This establishment/recruitment pattern suggests that mesic and xeric establishment at foreign sites is constrained by the interplay of seed and site limitations. Notably, soil surface disturbance facilitated establishment and recruitment of the xeric genotype while limiting the mesic genotype across all sites. Our results highlight the importance of seed size and dormancy as key factors impacting seedling establishment and adult recruitment, suggesting a potential interactive relationship between these traits.

Biology of the invasive species Eragrostis plana in Southern Brazil: What have we learned and how may this help us manage it?

AbstractSince its accidental introduction in 1951, the South African species Eragrostis plana has invaded a large part of the Pampa biome in South America, a highly diverse grassland ecosystem that has coexisted with livestock since its introduction at the beginning of the 17th century. E. plana, a perennial tussock grass with a deep and abundant root system, is resistant to frost and cattle grazing, and a successful competitor for environmental resources. The species is diploid, C4 dispersed endozoochorically, and flowers in late spring and early summer, with optimal germination occurring at 35°C and viability up to 39–40°C. It is allelopathic because it produces several phenols and alkaloids. Extreme soil disturbance or intense grazing favours initial invasion. Nonetheless, grazing exclusion enhances E. plana competition and affects the grassland community and diversity. E. plana is highly tolerant to interspecific competition, especially with grasses exhibiting a similar growth habit. Under water stress, it responds faster by increasing its root system by 66% more than native grass. Moreover, antioxidant system activity increases, and the species recovers quickly through osmolyte production. In non‐invaded fields, avoiding soil disturbance and intensive grazing are key strategies to preserving Biome Pampa. Nonetheless, in fields where the invasion has already occurred, grazing must be maintained, cattle quarantined practiced, along with strategies that reduce cover and prevent the spread of E. plana. Liming and fertilising native grasslands improve their potential to compete with E. plana. The wiper applicator, a device that allows glyphosate herbicide application selectively to E. plana, is an important component of the integrated weed management system, especially with very severe infestations. Establishing strategies to contain or manage E. plana should be a priority to preserve the biodiversity of the Pampa. In the future, innovative options could also help prevent new invasions.

The very early-succession herbaceous vegetation in the ‘Vaia’ windstorm clearings within the Italian southeastern pre-Alpine mountain belt (Veneto and Trentino)

Abstract The very early herbaceous vegetation which established in the clearings following 2018 ‘Vaia’ storm was investigated in some pre-Alpine areas of Northeast Italy, on calcareous as well as acidic substrata. Sixty-two original vegetation-plot records were executed in spruce or mixed beech-silver fir-spruce blowdown forests, within two years after the salvage logging had been completed. According to different origin and degree of soil disturbance, different communities were recognised. Galeopsis pubescens and G. tetrahit rich stands develop as ephemeral annual associations at the beginning of the regeneration succession where partially decomposed coniferous needles and twigs have accumulated in the litter. Soils with altered profiles due to forestry machineries harbour dominance of perennial herbaceous species (especially Senecio nemorensis agg., Atropa bella-donna, Epilobium angustifolium) which origin as many already recognised associations or vegetation types we ascribed to community level. All coenoses belong to Epilobietea angustifolii class, with the exception of Calamagrostis arundinacea-rich stands on undisturbed base-rich as well as base-poor soils, whose syntaxonomic positions are unclear.

Conversion of Marginalized Tea Lands into Timber Plantations and its Impact on Soil Organic Carbon Content: A Case Study in Central Highlands of Sri Lanka

Tea (Camellia sinensis) plantations can be in production for about 100 years under well-managed conditions. However, soil degradation makes the tea lands marginalized and uneconomical. Land use conversion is an option for marginalized tea lands that could gain numerous environmental and economic benefits. This study estimated and compared the soil organic carbon stocks (SOC) in the surface soil layer (0–30 cm) of marginalized tea lands against those converted to timber plantations in the Badulla and Nuwaraeliya districts. Disturbed and undisturbed soil samples were collected from the top layer (0-30 cm) of the selected sites of marginalized tea lands and those converted to timber plantations for analysis. Organic matter percentage in the site-level dry soil samples was analysed using the loss on ignition method. The final carbon stocks (t C ha-1) for samples from both land use types were then estimated using the SOC percentages and bulk density estimates. The carbon stocks for the soil samples collected at marginalized tea lands and the marginalized tea lands converted to timber plantations were then statistically analysed (descriptive statistics, normality tests and two-sample t-tests) using Minitab 21.2 software. The pH of marginal tea lands (5.34±0.14) and the marginal tea lands converted to timber plantations (5.20±0.13) was slightly acidic in nature. The bulk density estimates of marginalized tea lands and marginalized tea lands converted to timber plantations were very close and estimated as 1.15±0.02. The statistical analysis showed that overall mean SOC was significantly higher under the marginalized tea lands converted to timber plantations (155.3±10.0 t C ha-1) compared to the marginalized tea lands (126.7±5.8 t C ha-1). Land use conversion has increased the SOC stocks gradually after forest establishment. The increased carbon stocks could be attributed to consistent addition of litter layer on the soil, less soil disturbance, and retarded soil erosion contributing to the buildup of soil organic matter and SOC. On the other hand, low carbon stocks in the marginalized tea land could be attributed to unsustainable agronomical practices. Our findings suggest that converting marginalized tea lands in central highlands into timber plantations could enhance the sequestration of atmospheric CO2, significantly contributing to climate change mitigation.
 Keywords: Soil organic carbon, Land use change, Climate change, Tea plantations

Organic Carbon Storage and Structural-Hydraulic Properties of Ultisol under Agricultural Land Use Systems at Umuahia

The extent and pattern of interaction among organic carbon, structural and hydraulic properties of soils under varying land use systems are of great concern in the overall management of soil fertility and productivity. This study was conducted to examine the relationship among soil organic carbon storage, structural and hydraulic properties of soils under different agricultural land use systems at Umuahia, Abia State. The treatments were the four (4) land use systems (continuously cultivated arable farmland, 3 – year fallow land, oil palm plantation, and forest land) in which nine (9) replicates each of disturbed and undisturbed soil samples were randomly collected to give thirty six observational units laid out in a randomized complete block design. The soil samples were prepared and analysed in the laboratory. Analyses of variance, regression and correlation analyses were conducted on the data collected using Genstat version 14 and SPSS version 20. Results show that organic carbon had significant positive relationship with saturated hydraulic conductivity, macro porosity and total porosity but significant negative relationship with bulk density at all the land use systems. However, the influence of organic carbon on the other parameters was greatest at continuously cultivated arable land followed by the 3 – year fallow land. There is need to increase organic matter input at the continuously cultivated arable land and 3 – year fallow land through increased organic manuring and extension of the fallow period, respectively.

Hydrosedimentological monitoring in runoff plots of a degraded tropical area under restoration of the Brazilian Atlantic Forest

Rainfall erosion is a concerning process for landowners, government agencies and civil society as it involves soil loss, an indispensable natural resource for the production of food, fibers, and biofuels, as well as a means to support enterprises or even preservation of large conservation areas for sustainability and potential carbon sink. Specific Projects using runoff and soil loss plots have been adopted in different parts of the world, contributing to the understanding of erosion dynamics. This research is the result of extensive fieldwork carried out on a rural property undergoing forest restoration through a Payment for Environmental Service initiative. Four runoff plots with dimensions of 22m x 4m x 0.5m (length x width x depth) connected to sediment catchment tanks were implemented on a convex slope to analyze erosion in four different treatments: planting native seedlings, seedlings with green manure, natural regeneration with selective pruning, and exposed soil. The results of monitoring over approximately one year showed that 80.15% of all accumulated surface runoff occurred in the plot with exposed soil, as well as 99.15% of all soil loss. The treatment that presented the best conservation rates was natural regeneration, since there was no need to dig holes to introduce seedlings, causing less soil disturbance. Thus, it was concluded that land use and changes in land use are one of the main factors controlling erosion and surface runoff in the study area, however, in the long term, variations in soil properties due to vegetation may reflect more strongly this dynamic.

Environmental change legacies attenuate disturbance response of desert soil microbiome and multifunctionality

Abstract Deserts are predicted to be one of the ecosystems most vulnerable to global climate change, with dramatic fluctuations of temperature and water, even over the span of a single day. These previous disturbances could influence the response of the soil microbiome and its functions to subsequent disturbances, which is known as legacy effect. However, how legacy effects shape the response of soil microbiome and its functions to environmental fluctuations (e.g. temperature and water availability) in desert ecosystems remains to be investigated. Here, we firstly exposed desert soils to drought, freezing or their combination, and then followed by a second disturbance, resulting in a temporally full factorial treatment. We found that environmental change legacies affected the response of soil multifunctionality, microbial abundance and richness to second drought and freezing, except for eukaryotic richness. Initial disturbances caused legacy effects on microbial composition and weakened their responses to later disturbances, and these effects were stronger for prokaryotes than eukaryotes. The attenuated response to later disturbances is largely due to that almost half of the taxa affected by the earlier disturbances were also affected by the second disturbances. The phylogenetic depth of these responses varied minimally among the types of disturbances but were more conserved for negative responses, indicating a result of historical adaptation. Moreover, the altered community composition was associated with functional changes in the disturbed soils. These findings will improve our understanding of the mechanisms underlying the legacy impacts of multiple environmental disturbances on desert microbial communities and strengthen our ability to develop management strategies for protection prior to disturbance events. Read the free Plain Language Summary for this article on the Journal blog.