Changes In Moisture Research Articles

Integrating Multi-Source Remote Sensing Data for Forest Fire Risk Assessment

Forest fires are a frequent and destructive phenomenon in Southwestern China, posing significant threats to ecological systems and human lives and property. In response to the growing need for effective forest fire prevention, this study introduces an innovative method for predicting and assessing forest fire risk. By integrating multi-source data, including optical and microwave remote sensing, meteorological, topographic, and human activity data, the approach enhances the sensitivity of risk models to vegetation water content and other critical factors. The vegetation water content is derived from both Vegetation Optical Depth and optical remote sensing data, allowing for a more accurate assessment of changes in vegetation moisture that influence fire risk. A time series prediction model, incorporating attention mechanisms, is used to assess the probability of fire occurrence. Additionally, the method includes fire spread simulations based on Cellular Automaton and Monte Carlo approaches to evaluate potential burn areas. This combined approach can provide a comprehensive fire risk assessment using the probability of both fire occurrence and potential fire spread. Experimental results show that the integration of microwave data and attention mechanisms improves prediction accuracy by 2.8%. This method offers valuable insights for forest fire management, aiding in targeted prevention strategies and resource allocation.

Physicochemical perturbation increases nitrous oxide production from denitrification in soils and sediments

Abstract. Atmospheric concentrations of nitrous oxide (N2O), a potent greenhouse gas that is also responsible for significant stratospheric ozone depletion, have increased in response to the intensified use of agricultural fertilizers and other human activities that have accelerated nitrogen cycling processes. Microbial denitrification in soils and sediments is a major source of N2O, produced as an intermediate during the reduction of oxidized forms of nitrogen to dinitrogen gas (N2). Substrate availability (nitrate and organic matter) and environmental factors such as oxygen levels, temperature, moisture, and pH influence rates of denitrification and N2O production. Here we describe the role of physicochemical perturbation (defined here as a change from the ambient environmental conditions) in influencing rates of denitrification and N2O production. Changes in salinity, temperature, moisture, pH, and zinc in agricultural soils induced a short-term perturbation response characterized by lower rates of total denitrification and higher rates of net N2O production. The ratio of N2O to total denitrification (N2O : DNF) increased strongly with physicochemical perturbation. A salinity press experiment on tidal freshwater marsh soils revealed that increased N2O production was likely driven by transcriptional inhibition of the nitrous oxide reductase (nos) gene and that the microbial community adapted to altered salinity over a relatively short time frame (within 1 month). Perturbation appeared to confer resilience to subsequent disturbance, and denitrifiers from an environment without salinity fluctuations (tidal freshwater estuarine sediments) demonstrated a stronger N2O perturbation response than denitrifiers from environments with more variable salinity (oligohaline and mesohaline estuarine sediments), suggesting that the denitrifying community from physicochemically stable environments may have a stronger perturbation response. These findings provide a framework for improving our understanding of the dynamic nature of N2O production in soils and sediments, in which changes in physical and/or chemical conditions initiate a short-term perturbation response that promotes N2O production that moderates over time and with subsequent physicochemical perturbation.

Assessment of Soil Moisture in Vegetation Regions of Mu Us Sandy Land Using Several Aridity Indicators

Drought, a significant calamity in the natural domain, has extensive worldwide repercussions. Drought, primarily characterized by reduced soil moisture (SM), presents a significant risk to both the world environment and human existence. Various drought indicators have been suggested to accurately represent the changing pattern of SM. The study examines various indices related to the Drought Severity Index (DSI), Evaporation Stress Index(ESI), Vegetation Supply Water Index(VSWI), Temperature-Vegetation Dryness Index(TVDI), Temperature Vegetation Precipitation Dryness Index(TVPDI), Vegetation Health Index(VHI), and Temperature Condition Index (TCI). An evaluation was conducted to assess the effectiveness of seven drought indicators, such as DSI, ESI, TVPDI, VSWI, etc., in capturing the changes in SM in Mu Us Sandy Land. The research results indicated that DSI and ESI had the highest accuracy, while TVDI and VSWI showed relatively lower accuracy. However, their smaller fluctuations in the time series demonstrated stronger adaptability to different regions. Additionally, the delayed impact of aridity indices on soil moisture, variable attributes, temperature, and vegetation coverage in sandy land and grassland areas with low, medium, and high coverage all contributed to the effectiveness of the four aridity indices (DSI, ESI, VSWI, and TVPDI) in capturing the dynamics of soil moisture. The primary element that affects the effectiveness of TVDI is the divergence of the relationship curve between Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI), which is a kind of deterioration. This paper presents a very efficient approach for monitoring soil moisture dynamics in dry and semi-arid regions. It also analyzes the patterns of soil moisture changes, offering valuable scientific insights for environmental monitoring and ecological enhancement.

Unraveling the Relationships Between Trend of Dam Inflows, Hydrometeorological Variables and Vegetation in West and Southwest United States

Abstract This paper explored temporal changes in magnitude and seasonality of low, median, and high inflows of 51 dams across the West and Southwest United States over the 1993-2022 period. Changes in precipitation, air temperature (an indicator of snowpack and evaporation), soil moisture, and vegetation were also examined to identify potential reasons for the temporal trends in dam inflows. Using monotonic and non-monotonic tests, we found a general downward trend in dam inflows, particularly across the Upper Colorado and California regions. More than 30% of the dams showed a downward trend in their annual median inflows, high inflows during spring, and median inflows during fall. The downward trend of dam inflows was associated with decreasing precipitation and soil moisture, and rising temperatures. While vegetation exhibited positive associations with inflows, it did not seem to be a primary factor for explaining the inflow trends. We also observed shifts in the seasonality of low and high inflows; there was an increase in the proportion of inflows occurring during summer and fall, and a decrease in winter proportions for low inflows. Similarly, high inflows exhibited an increase in spring proportions and a decrease in fall proportions. Our changepoint analyses detected non-monotonic trends between 2002 and 2012 in ~13% of the dams; the majority were located in the Upper Colorado and California regions. More than half of these changepoints were in 2011, likely due to widespread droughts then. Our study has implications for reservoir managers to identify changes that dams experience over time and assist them in proposing actions that maintain the dams’ functionality.

Diaspore Dimorphism, Awn Hygroscopicity and Adaptive Significance in a Winter Annual Bromus tectorum (Poaceae).

Bromus tectorum, a winter annual plant, produces dimorphic diaspores: complex diaspores with multi-awns and simple diaspores with one awn. However, there is no information available about the role of awns and the germination characteristics of dimorphic diaspores. Dispersal germination and awns hygroscopicity of the dimorphic diaspores were assessed. The complex diaspore with multi-awns can easily be dispersed long distances from the mother plant by mammals. The simple diaspores with one awn are tightly attached to the mother plant. Caryopses from the two types of diaspores exhibited non-deep physiological dormancy at maturity, which can be released by dry storage and GA3 treatment. The awns have hygroscopic activity and can move in response to changes in moisture, moving the complex diaspore (the seed) into the soil. The seedling emergence from complex diaspores was significantly higher than those from simple diaspores at all burial depths. Germination of caryopses on the soil surface was poor. The optimal planting depth for both types of diaspores' emergence is 1-2 cm. The distinct characteristics of dimorphic diaspores and the beneficial influence of hygroscopic awns on dispersal, germination, and seedling establishment have significant ecological implications for B. tectorum's successful reproduction in unpredictable cold deserts.

“Aging” in co-amorphous systems: Dissolution decrease and non-negligible dissolution increase during storage without recrystallization

Developing co-amorphous systems is a promising strategy to improve the water solubility of poorly water-soluble drugs. Most of the studies focused on the initial dissolution rate of the fresh co-amorphous systems, and only physical stability was investigated after storage. However, the maintenance of the enhanced dissolution rate of co-amorphous systems after storage is necessary for further product development. The maintenance of amorphous forms after storage does not always mean the maintenance of the dissolution rate. In this study, indomethacin, arginine, tryptophan, and phenylalanine were used as the model drug and the co-formers to prepare co-amorphous systems and then stored under dry condition and RH 60 ± 5 % condition. No recrystallization was observed after the storage for 40 d and 80 d. Interestingly, both intrinsic dissolution rate (IDR) decrease and unexpected increase after storage were confirmed. The further mixing of IND and the co-former at a molecular level and the moisture changes of the co-amorphous systems during storage were supposed to play important roles in the aging. This study reminds us that the possible dissolution changes (both dissolution decrease and increase) of co-amorphous systems during storage should be carefully considered, though these samples maintained amorphous forms.

Devising a method for determining the moisture conductivity coefficient of subgrade soils taking into account European approaches and standards

The object of this study is the theoretical and methodological approaches to determining the coefficient of moisture conductivity of subgrade soils. The work focuses on considering the European approaches and standards when devising a method for determining the coefficient of moisture conductivity of soils. In the course of the research, a method was developed for determining the coefficient of moisture conductivity of soils K1, which characterizes the diffusion movement of water, through the filtration coefficient K0, calculated in accordance with European requirements based on laboratory test data. The proposed method is based on a mathematical model built on the basis of the differential equation of changes in soil moisture. The model is special in that, unlike existing ones, the movement of water was modeled from the bottom up, which reflects the process of moisture accumulation in the lower layers of the subgrade from groundwater or topwater. A good agreement of the mathematical model with the data by other authors was obtained (the relative error did not exceed 12.98 %). A direct relationship between the moisture conductivity coefficient of soils K1 and their initial moisture content W0 and an inverse relationship between K1 and the total moisture capacity of soils WFH were established in the paper. Dependences were derived in the range of changes in initial soil moisture W0 from 0.08 to 0.15 and WFH from 0.15 to 0.5. It was found that the values of the moisture conductivity coefficient of soils K1 increase from 4.64·10-6 to 3.81·10-5 m2/h with an increase in their initial moisture content and with a decrease in total moisture capacity. From the point of view of engineering practice of road construction, the proposed method makes it possible to predict seasonal changes in soil moisture in the subgrade, to determine the strength of the road structure. This makes it possible to make sound design decisions on the installation of drainage systems on roads in order to extend their service life

Spatiotemporal Changes in Vegetation Cover and Soil Moisture in the Lower Reaches of the Heihe River Under Climate Change

As global climate change intensifies, arid land ecosystems face increasing challenges. Vegetation, a key indicator of climate variation, is highly responsive to meteorological factors such as temperature (Tem), precipitation (Pre), and soil moisture (SM). Understanding how fractional vegetation cover (FVC) responds to climate change in arid regions is critical for mitigating its impacts. This study utilizes MOD13Q1-NDVI data from 2000 to 2022, alongside corresponding Tem, Pre, and SM data, to explore the dynamics and underlying mechanisms of SM and FVC in the context of climate change. The results reveal that both climate change and human activities exacerbate vegetation degradation, underscoring its vulnerability. A strong correlation between FVC and both Tem and Pre suggests that these factors significantly influence FVC variability. In conclusion, FVC in the lower reaches of the Heihe River is shaped by a complex interplay of Tem, Pre, SM, and human activities. The findings provide a scientific basis and decision-making support for ecological conservation and water resource management in the lower reaches of the Heihe River, aiding in the development of more effective strategies to address future climate challenges.

Development of Electrically Conductive Wood-Based Panels for Sensor Applications.

This study investigates the development of electrically conductive panels for application as emergency detection sensors in smart house systems. These panels, composed of wood chips coated with polymeric methylene diphenyl isocyanate, were modified with carbon black and carbon fibers to enable detection of moisture, temperature, and pressure variations. Manufactured via hot pressing, the panels retained standard mechanical properties and exhibited stable performance under diverse environmental conditions. Carbon black-filled panels achieved electrical percolation at a lower filler concentration (5%) compared to carbon fiber-filled panels. The incorporation of carbon black reduced the electrical resistivity to 8.6 ohm·cm, while the addition of carbon fibers further decreased it to 7.7 ohm·cm. In terms of sensor capabilities, panels containing carbon fibers demonstrated superior sensitivity to moisture and pressure changes. However, carbon black was ineffective for temperature sensing. Among the carbon fiber-filled panels, those with 20 wt.% concentration exhibited the best performance for moisture and pressure detection, whereas panels with 40 wt.% carbon fiber content displayed the most reliable and consistent temperature-sensing properties.

Major moisture shifts in inland Northeast Asia during the last millennium

Abstract Previous paleoenvironmental data synthesis indicates that arid central Asia (“westerlies Asia”) and mid-latitude East Asia (“monsoonal Asia”) show anti-phased moisture variations over the last millennium. However, there are very few records from inland Northeast Asia, which obscures the spatial extent of or the boundary between the two domains and hinders the assessment of climate change impacts and consequences across the region. Here, we present a multi-proxy record that combines peat properties, plant macrofossils, and isotopic ratios of Sphagnum moss cellulose from a unique precipitation-fed peatland in northern Northeast China to fill this critical data gap. The results show major centennial-scale moisture anomalies at this site, with drier and wetter conditions during the Medieval Warm Period and Little Ice Age, respectively, which resemble the pattern of moisture changes in “westerlies Asia”. During the period of rapid anthropogenic warming, the site is much drier, with isotopic evidence for threshold-like summer desiccation of peat-forming Sphagnum mosses. This study provides the long-term context and identifies the large-scale pattern of moisture variability in an inland region home to carbon-rich peatlands, forests, and permafrost soils, and highlights their potential vulnerability to future warming-enhanced drying that can be transmitted widely through atmospheric teleconnection.

Soil moisture content and its temporal stability in an arid aerial seeding afforestation area after 30 years vegetation restoration in China

Soil moisture is a critical factor for vegetation restoration in arid regions. Poorly planned artificial sand-fixing vegetation systems often exacerbate soil moisture depletion, leading to further degradation. In this study, soil moisture content at various depths was continuously monitored from June to October 2023 in four key community plots—Corethrodendron scoparium, Calligonum mongolicum, and Artemisia ordosica, and bare sand—in a 31-year-old revegetated area located on the northeastern edge of the Tengger Desert. We analyzed the distribution and dynamic changes of soil moisture across the different and evaluated its temporal stability. The representative soil moisture depth was determined by using the coefficient of determination (R2) and the Nash-Sutcliffe efficiency (NSE). The results showed significant differences in soil moisture among the four plots. The bare sand plot had the highest soil water storage in the 0-200 cm layer, at 46.37 mm. In contrast, the Corethrodendron scoparium, Calligonum mongolicum, and Artemisia ordosicaa plots had similar soil water storage values ranging from 33.50 to 33.67 mm, indicating that vegetation restoration has increased soil moisture absorption by an average of 27.4%. Analysis using relative difference and Spearman rank correlation methods revealed varying levels of temporal stability in soil moisture across different soil depths and plots. The Corethrodendron scoparium and bare sand plots showed higher temporal stability compared to the Calligonum mongolicum and Artemisia ordosica plots. The representative depths of temporal stability for the four plots were determined to be 100 cm, 150 cm, 20 cm, and 100 cm, respectively.

Comparing MJO Intensity over the Tropical Western Pacific during Mega and Equatorial La Niña Winters

Abstract This study investigated variations in the Madden–Julian oscillation (MJO) behavior between two types of La Niña winters: mega and equatorial La Niñas. Results of this work show that in contrast to mega conditions, accompanied by more abundant intraseasonal column-integrated moisture anomalies over the planetary boundary layer, intensities of intraseasonal outgoing longwave radiation anomalies are stronger over the tropical western Pacific (WP) at MJO phases 5–6 under equatorial conditions. The occurrence of the moisture anomaly change averaged over the tropical WP is supported by a distinct moisture tendency difference. Moisture budget and multiscale interaction diagnoses underscore the pivotal effect of an area-averaged vertical gradient change in low-frequency background moisture in driving such tendency change. Considering notable MJO convection variations, the teleconnections associated with MJO phases 5–6 over East Asia (EA) were also explored, including warmer surface air temperature anomalies and stronger positive geopotential height anomalies at 200 hPa on the intraseasonal time scale under equatorial conditions. Results from a linear baroclinic model demonstrate that such teleconnection changes could be effectively explained by the linear response to the MJO’s diabatic heating anomaly. Roles of mean state and MJO itself variations in the linear response change are also discussed. These findings provide novel insights into MJO activity and offer potential improvements for subseasonal forecasting in EA. Significance Statement The relationship between El Niño–Southern Oscillation (ENSO) and MJO has been extensively explored recently. However, variations in the MJO behavior and its climate effects under mega and equatorial La Niña winters have not been thoroughly investigated. In this work, we utilized reanalysis datasets and an idealized linear baroclinic model to address these questions. We observed more robust and abundant intraseasonal convection activity and planetary boundary layer–integrated moisture anomaly averaged over the tropical WP at MJO phases 5–6 under equatorial conditions than mega conditions, which is closely linked with the vertical gradient change in low-frequency background moisture. Additionally, MJO-related teleconnections also exhibit some changes. This work may provide a new perspective on understanding the relationship between the MJO and ENSO and offer potential improvements for the subseasonal forecast.

Effects of temperature and drought stress on the seed germination of a peatland lily (Lilium concolor var. megalanthum).

Sexual reproduction through seeds is an effective way to renew plant populations and increase their genetic diversity, but seed germination process is complicated and relatively difficult due to the restriction of environmental conditions. Wetland plants that reproduce sexually through seeds may be affected by changes in moisture and temperature. This study aims to explore the ecological adaptation strategies of seed germination of Lilium concolor var. megalanthum under different hydrothermal conditions. Controlled experiments were conducted to investigate the germination performance of L. concolor var. megalanthum seeds at different temperatures (10°C, 15°C, 20°C, 25°C, and 30°C) and simulated drought stress conditions using PEG-6000 solutions (0%, 5%, 10%, 15%, and 20%). The results showed that temperature, drought stress, and their interaction significantly affected the days to first germination, germination percentage, coefficient of germination rate, germination energy, germination index, and vigor index of seeds (p<0.01). The germination percentage, germination index, and vigor index of seed were significantly higher at 25°C compared to other temperatures (p<0.01). The interaction between low temperature and drought stress significantly delayed the days to first germination. The inhibition of drought stress on seed germination was enhanced by PEG-6000 solution under high temperature. Under the conditions of 25°C and 5% PEG-6000 solution concentration, seeds of L. concolor var. megalanthum exhibited optimal germination parameters. At 10°C and 15°C, the seeds exhibited the highest tolerance to PEG-6000-simulated drought stress. Rehydration germination results showed that extreme temperatures and drought stress conditions inhibit seed germination of L. concolor var. megalanthum without damaging seed structure. The germination pattern of seeds under variable temperature and drought stress conditions reflects their adaptive strategies developed over long-term evolution to cope with the environmental conditions.

Forecasting Soil Moisture in Caragana Shrubland Using Wavelet Analysis and NARX Neural Network

It is important for sustainable use of soil water resource and high-quality development to forecast the soil moisture in forestland of water-limited regions. There are some soil water models. However, there is not the best model to forecast the change of soil moisture in the caragana shrubland. In this paper, the plant water relationship has been investigated at the same time for a long term in the caragana shrubland of semiarid region of the Loess Plateau of China. The data of soil moisture was divided and then NARX neural network was used to build model I and model II. For model I, low frequency component was the input variable, and for model II, low frequency component and high frequency component were predicted. The results showed the average relative error for model I is 3.5% and for model II is 0.3%. The average relative error of predicted soil moisture in 100 cm layer using model II is 0.8%, then soil water content in the 40 cm and 200 cm soil depth is selected and the forecast errors are 4.9% and 0.4%. The results showed that using model II to predict soil water is well Predicting soil water using model II will be important for sustainable use of soil water resource and high-quality development.

The intricacies of vegetation responses to changing moisture conditions.

A long-standing debate looks at whether air or soil dryness is more limiting to vegetation water use and productivity. The answer has large implications for future ecosystem functioning, as atmospheric dryness is predicted to increase globally while changes in soil moisture are predicted to be far more variable. Here, I review the complexities that contribute to this debate, including the strong coupling between atmospheric and soil dryness, and the widespread heterogeneity in vegetation hydraulic traits, acclimations, and adaptations to water stress. I discuss solutions to improve understanding and modeling of vegetation sensitivity to dryness, including how different types of observational data can be used together to gain insight into vegetation response to water stress across spatial and temporal scales.

Effects of Moisture Migration and Changes in Gluten Network Structure during Hot Air Drying on Quality Characteristics of Instant Dough Sheets.

The impact of hot air drying temperature on instant dough sheets' qualities was investigated based on water migration and gluten network structure changes. The results revealed that the drying process redistributed the hydrogen proton, with deeply bound water accounting for more than 90%. The T2 value decreased as the drying temperature increased, effectively restricting moisture mobility. Meanwhile, microstructural analysis indicated that instant dough sheets presented porous structures, which significantly reduced the rehydration time of instant dough sheets (p < 0.05). In addition, elevated drying temperatures contributed to the cross-linking of proteins, as evidenced by increased GMP and disulfide bond content (reaching a maximum at 80 °C), which improved the texture and cooking properties. Hence, the water mobility was effectively reduced by controlling the drying temperature. The temperature had a facilitating impact on promoting the aggregation of the gluten network structure, which improved the quality of the instant dough sheets.

Multifaceted Analysis of the Impact of Recent Changes in Climate and Soil Moisture on the Seed Yield of Tanba Black Soybeans in Tanba-sasayama City

Multifaceted Analysis of the Impact of Recent Changes in Climate and Soil Moisture on the Seed Yield of Tanba Black Soybeans in Tanba-sasayama City

Real-time quality analysis of baked goods using advanced technologies

Some critical quality variables of baked goods baked in tunnel ovens cannot be monitored in real-time and quickly after baking. Generally, these variables are measured individually and manually. Analysis of some variables can be done in laboratory environments. It is very difficult to continuously and accurately read the quality variables of products, especially at the exits of industrial tunnel ovens operating at high speeds. With current systems, important quality variables of the products are assessed through widely spaced sampling, and most of the time the measurements made do not represent the entire batch. Additionally, interventions in the process may be delayed due to the time required for analysis, allowing defective products to reach consumers. In this study, experiments were carried out to enable real-time and high-speed identification of important quality variables such as product geometry, surface color, image features, and moisture. The developed system aims to monitor products such as cookies, cakes, biscuits, crackers and bread. Through this system, the size of the products that can represent the lot or even the entire batch can be analyzed when desired. Thus, quality oscillations can be kept within very narrow ranges. The developed hybrid system is applied to the exit of tunnel ovens, and the data read through sensors and cameras are transferred to computers using specially developed algorithms through interfaces. It has been observed that process control signals can also be generated by considering the lower and upper control limits of quality variables. With the developed software, changes can be instantly seen on the screens in the form of graphics, audio, and visual warnings can be created, historical data can be recorded, and reports can be obtained. At the end of the study, it was found that important quality variables such as circularity, diameter, thickness, color, image area, and moisture could be read with a sample size of up to 100%. As a result of the experiments, it was seen that the change in product diameters could be defined within the range of 40.30±0.5 mm. The circularity ratio between horizontal and vertical diameters can be monitored within 1.008 ± 0.018%. The change in moisture within the range of 2.741±0.164 g/100g. The light-dark image area ratios within the range of 0.486±0.033%, and the product thickness within the range of 11.56±0.178 mm. Resultly, all critical quality parameters taken into account can be detected within a range that will not affect product and process quality.

TRACER Perspectives on Gulf-Breeze and Bay-Breeze Circulations and Coastal Convection

Abstract This study explores gulf-breeze circulations (GBCs) and bay-breeze circulations (BBCs) in Houston–Galveston, investigating their characteristics, large-scale weather influences, and impacts on surface properties, boundary layer updrafts, and convective clouds. The results are derived from a combination of datasets, including satellite observations, ground-based measurements, and reanalysis datasets, using machine learning, changepoint detection method, and Lagrangian cell tracking. We find that anticyclonic synoptic patterns during the summer months (June–September) favor GBC/BBC formation and the associated convective cloud development, representing 74% of cases. The main Tracking Aerosol Convection Interactions Experiment (TRACER) site located close to the Galveston Bay is influenced by both GBC and BBC, with nearly half of the cases showing evident BBC features. The site experiences early frontal passages ranging from 1040 to 1630 local time (LT), with 1300 LT being the most frequent. These fronts are stronger than those observed at the ancillary site which is located further inland from the Galveston Bay, including larger changes in surface temperature, moisture, and wind speed. Furthermore, these fronts trigger boundary layer updrafts, likely promoting isolated convective precipitating cores that are short lived (average convective lifetime of 63 min) and slow moving (average propagation speed of 5 m s−1), primarily within 20–40 km from the coast.

Natural Recovery Dynamics of Alfalfa Field Soils under Different Degrees of Mechanical Compaction

Soil compaction in alfalfa fields has become increasingly severe due to the mechanization of animal husbandry and the increased use of heavy agricultural machinery. Perennial alfalfa land undergoes mechanical compaction several times during the planting period without mechanical tillage. The compacted soil structure may recover through moisture changes, freezing and thawing cycles, and plant growth, but the extent and rate of this recovery remain unknown. In this study, alfalfa plots with two different soil types (medium loam and sandy) in Gansu, China, were selected to address these issues. The areas of the plots were 120 m × 25 m and 80 m × 40 m, respectively. In the third year after sowing, three types of agricultural machinery with grounding pressures of 88 kPa, 69 kPa, and 48 kPa were used to compact the soil one, three, five, and seven times. The interval between replicates was 1 h. Each treatment had one plot of 10 m × 5 m, and the experiment was repeated 4 times, totaling 44 plots. Changes in soil bulk density, soil cone index, and saturated hydraulic conductivity were measured after 1, 4, 8, and 17 weeks, respectively. The results showed that the post-compaction soil bulk density and soil cone index largely influenced the recovery of the compacted soil. Recovery became problematic once the soil bulk density exceeded 1.5 g/cm3. The soil bulk density recovery rate varied across different soil layers, with the top layer recovering faster than more profound layers. The initial state could be restored when the change in post-compaction soil bulk density was minimal. Sandy soil recovered faster than medium-loam soil. The recovery of the soil cone index in each layer of medium-loam soil under lower compaction was more noticeable than that under severe compaction. However, with undergrounding pressures of 88 kPa and 69 kPa, the soil cone index could not fully recover after multiple compactions. The recovery of soil-saturated hydraulic conductivity in both soil types was slower and less pronounced. The recovery of soil-saturated hydraulic conductivity in medium-loam soil was slower than that in sandy loam. After 7 compactions and 17 weeks under a grounding pressure of 88 kPa, the saturated hydraulic conductivity remained below 20% of its initial value of 20 mm/h. In contrast, sandy soils recovered faster, reaching 60 mm/h within a week of each compaction event. This research is crucial for ensuring high and stable alfalfa yields and supporting sustainable agricultural practices.