Next Article in Journal
Natural Variation in the AAT1 Promoter Is Responsible for the Disparity in Ester Aroma Between Actinidia chinensis and Actinidia eriantha
Previous Article in Journal
Sowing Rates and Methods Affect Yield and Forage Quality of American Jointvetch in the Southwestern Area of Japan
Previous Article in Special Issue
Long-Term Agricultural Management Alters Soil Fungal Communities and Soil Carbon and Nitrogen Contents in Tea Plantations
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Agronomy
Volume 14
Issue 12
10.3390/agronomy14122964
agronomy-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Long-Term Application of an Oil Residue Organic Fertilizer Improved Soil Physical Properties in the Root Zone of Jujube Trees

by
Huadong Zhang
1,
Shaoliang Zhou
1,
Weixiong Huang
2,
Zhu Zhu
1,
Kaixuan Li
1 and
Sanmin Sun
1,*
1
Modern Agricultural Engineering Key Laboratory at Universities of Education Department of Xinjiang Uygur Autonomous Region, College of Water Hydraulic and Architectural Engineering, Tarim University, Alar 843300, China
2
MOE Key Laboratory of Groundwater Quality and Health, School of Environmental Studies, China University of Geosciences, Wuhan 430078, China
*
Author to whom correspondence should be addressed.
Agronomy 2024, 14(12), 2964; https://doi.org/10.3390/agronomy14122964
Submission received: 24 November 2024 / Revised: 10 December 2024 / Accepted: 10 December 2024 / Published: 12 December 2024
(This article belongs to the Special Issue Effects of Arable Farming Measures on Soil Quality)
Browse Figures
Review Reports Versions Notes

Abstract

:
Organic fertilizers have been widely applied in Chinese agriculture. Soil aggregate composition and pore size distribution indicate the effects of fertilizer practices on soil quality. While the effects of the long-term application of organic fertilizers on total soil pore space have been reported, few studies have examined the distribution of connected pore spaces (of critical importance for solute transport in the soil). Soil physical and chemical properties influence plant growth and soil processes. We compared the effects of organic fertilizer application (10 years, 5 years, and no application) on soil connectivity pore structures and physicochemical properties within the root zone (20–40 cm depth) around date palms through CT scanning or core samples. Specifically, when the number of years of organic fertilizer application increased, the proportion of 2–0.25 mm particle size aggregates in the soil increased, and soil connectivity pore structure became more complex and stable, with higher connectivity, pore numbers, and numbers of pore throats. The connectivity of particles of the 0–300 μm size class of pores increased and the proportion of the 500–1000 μm class of pore throats increased. Soil organic matter and enzyme activity were significantly related to soil pore structure characteristics. In conclusion, the application of organic fertilizer improved soil pore structures, and the effects became more pronounced with the increased duration of application. These results provide theoretical and practical support for the application of organic fertilizer to improve soil structures in arid areas, and the findings have significant implications for sustainable agriculture in arid and semi-arid regions.

1. Introduction

Fertilizer is an indispensable agricultural product that improves soil fertility and maintains crop yields, with crop yield being largely dependent upon it [1]. However, in China, the over-application of chemical fertilizers is a serious and widespread problem, as the quantities of fertilizer that are applied can exceed the needs of crops and contribute to degrading soil structures [2,3]. Soil aggregates are a basic unit of soil structure, and different-sized aggregates play different roles in soil nutrient supply, conservation, and transformation ability [4]. Soil pores are sites where water, nutrients, and gas are transported and stored, and they affect nutrient uptake and crop root growth [5]. Pore structure influences fluid volume, distribution, and transport in porous media, as well as fluid percolation [6]. Because changes in soil pore structure caused by agricultural land use and fertilizer application practices affect soil aggregates, carbon sequestration, microbial diversity, and resistance to wind and water erosion [7,8], it is not surprising that considerable research has been performed on soil aggregates and pore structure [9].
CT scanning technology enables soil porosity to be examined at a micrometer scale. Quantitative analyses of soil porosity, as well as pore size distribution, shape, and connectivity, can help in improving our understanding of the impact of agricultural management practices on the soil environment. However, to assess the impact of long-term organic fertilization on the soil environment, the evolution of soil pore structures induced by long-term fertilization practices must be explored.
Xinjiang is located in northwestern China, a region with low annual rainfall, an arid climate, and high evaporation, and its widespread salinized soils have poor soil structures [10]. Although the effects of fertilizer use on soil pore structures have been globally studied extensively, differences in soil, crop type, fertilizer type, and cropping practices between studies have produced variable conclusions. Xu [11] reported that the total surface soil macroporosity increased significantly following the application of organic fertilizer, with the number of 50–500 μm pores increasing over time, while biopores (>2000 μm) decreased significantly in number after 9 y of use in greenhouse vegetable plots. Wang [12] reported the proportions of macropores (>500 μm) to be the greatest after 22 y of organic fertilizer treatment. However, few studies have investigated the long-term effects of organic fertilizers on soil pore connectivity, particularly in arid and semi-arid regions.
Previous studies on pore structure have mostly focused on the establishment of three-dimensional models of overall pore space in soils and analyzing pore size distribution [13]. However, soil pore connectivity is an important indicator of water solute infiltration. The higher the pore connectivity, the higher the macroporous flow rate [14]. Soil connectivity pore spaces affect soil solute transport [15]. Understanding the effects of organic fertilizers on soil pore structure is crucial for sustainable agriculture, as it can improve soil water retention, nutrient cycling, and crop productivity. So, we use CT scanning technology to analyze soils in the root zone of date palm trees exposed to fertilizer for 5 and 10 y and compare this with soils that have received no organic fertilizer. We report the distributions of connecting pore apertures and compare the effects of different fertilizer application scenarios on soil physical and chemical properties (agglomerates, the distribution of connecting pore apertures, and pore throat network characteristics) to understand the effects of long-term fertilizer application on soil pore connectivity and how soil agglomerates and connecting pore apertures respond to organic fertilizers. The objectives of this study were to (1) evaluate the impact of long-term organic fertilizer application on soil physical properties, (2) analyze the changes in soil pore structure, and (3) investigate the relationship between soil organic matter, enzyme activity, and pore connectivity.

2. Materials and Methods

2.1. Experimental Area

The study area is located at the Irrigation Experimental Station, College of Water Resources and Architectural Engineering, Tarim University, Alar City, Xinjiang Production and Construction Corps, China (80°30–81°58′ E, 40°22–40°57′ N). The soil texture is sandy loam. The site is characterized by long sunshine hours, drought, low rainfall, and large differences in evapotranspiration and diurnal temperature. At this site, more than 100 date palms were planted in 2009. From 2013, organic fertilizer has been applied to some palms using a sand tube irrigation system (STI) buried at a 25 cm depth (Figure 1). The fertilizer application area was located near the lower part of the STI system at 30 cm depth (Figure 1). The number of effective viable bacteria (compound probiotics) in the fertilizer was ≥10 million/g, its organic matter content was ≥55%, its nitrogen content was 5.62%, its phosphorus pentoxide content was 1.37%, and its potassium oxide content was 2.25%, which was made by soybean oil residues. Fertilizer was applied in November each year at a rate of about 150 kg ha−1 by hole application, with the hole being about 30 cm deep. When irrigating with the STI system, the water source is located 25 cm below the ground surface. Because of the ‘hydrodynamic’ nature of the root system, under long-term irrigation conditions in this manner, the date palm root system develops at shallow depths, mostly from 20 to 40 cm. Because the soil structure in this soil layer affects water infiltration and palm growth, we investigated the effect of the long-term application of organic fertilizer on its physicochemical properties and pore structure.

2.2. Soil Collection and Physical and Chemical Property Testing

Three replicate soil columns (20–40 cm) were collected in October 2023 from the areas around date palms that had received organic fertilizer for 10 y (from 2013; OF10); three replicate columns were also collected from areas near date palms that had received organic fertilizer for 5 y (from 2018; OF5) and from areas near date palms that had never received organic fertilizer (CK). Samples were collected ~30 cm from the trees using a PVC sampler of diameter 30 mm and length 60 mm. After collection, cores were wrapped in plastic. Surplus soil from a sample was used to measure soil physicochemical properties (soil bulk density (BD), electrical conductivity (EC), organic matter (OM), soil sucrase (INV), and soil urease (URE) contents). Soil BD was determined by the ring knife method; the SOM was determined by the 0.8 M K2Cr2O7 oxidation method; EC was measured in a 1:5 soil/water suspension; URE was determined using the phenol-sodium hypochlorite colorimetric method; INV was determined using the 3,5-dinitrosalicylic acid colorimetric method [10]. Soil aggregates were separated into three aggregate grades (>2, 2–0.25, and <0.25 mm) from the bulk soils by wet sieving; meanwhile, the mean weight diameter (MWD) was determined as the sum of the weighted mean diameters of all fraction classes [4].

2.3. Image Scanning and Processing

Soil columns were scanned using an industrial nano-CT with a scanning tube voltage of 120 kV, a resolution of 50 μm, a current of 100 μA, and an exposure time of 150 ms; about 2000 slices for each column were obtained from scanning. ImageJ 1.8.0 software was used to convert RGB images into 8-bit grayscale images, which were then imported into Avizo 9.5 software to apply commands such as Non-Local and Unsharp Masking for noise reduction and filtering. The connected pores within the aggregates were performed to model the pore network using the ‘X-Pore Network Modeling’ extension of the Avizo software. In the pore network model of connected pores, the spheres and lines represent the pores and their connections, respectively, and the pore throat size is the length of the line. Various pore properties were calculated using the Avizo software [7]. Pore sizes were divided into 0–100, 100–200, 200–300,300–400, 400–500, 500–600, 600–700, 700–800, 800–900, and 900–1000 μm classes; pore throat sizes were divided into 0–300, 300–400, 400–500, 500–600, 600–700, 700–800, 800–900, and 900–1000 μm classes.

2.4. Data Processing and Analysis

All statistical analyses were performed using Excel 2021 and the Statistical Package for the Social Sciences (SPSS) version 26.0. Different parameters among different treatments were compared by a one-way analysis of variance (ANOVA), meanwhile, Fisher’s least significant difference (LSD) was used at the p < 0.05 level of significance. Linear fitting and graphing were performed using Origin 2021 Pro software.

3. Results

3.1. Changes in Soil Physical and Chemical Properties with Time

Basic soil physicochemical properties in the root zone over time are presented in Table 1. Soil bulk density (BD) was significantly reduced by 2.84% (p < 0.05) compared with that of CK after 10 years of organic fertilizer application, and soil electrical conductivity (EC) was significantly reduced by 38.37% (p < 0.05) and 13.40% (p < 0.05) compared with that of CK after 10 years of organic fertilizer application and 5 years of organic fertilizer application, respectively. Soil sucrase activity (INV) increased significantly after 10 years of organic fertilizer application (by 31.56% and 11.96%, respectively) compared with that of soil after 5 years of organic fertilizer application and CK; meanwhile, organic fertilizer application increased soil > 0.25 mm class soil aggregates and significantly increased 2–0.25 mm class soil aggregates (Table 2).

3.2. Quantifying Pore Morphology Following Fertilizer Application

With an increase in the number of years of applying organic fertilizer, soil pore structure complexity increased; additionally, soil porosity increased by 64.30% and 79.93% (p < 0.05) after 10 years of organic fertilizer application compared to soil with 5 years of application and CK, respectively (Table 3). This indicates that long-term organic fertilizer application improved topsoil structures (Figure 2). From connectivity pore and soil ball-and-stick network maps (Figure 2 and Figure 3), the application of organic fertilizer reduced large pore clusters and small pore clusters became more widely distributed; soil pore connectivity increased by 34.77% (10 y) and 2.39% (5 y) (83.02% (OF10), 63.07% (OF5)) compared with CK (61.60%) values; the number of connectivity pores increased by 45.43% (10 y) and 10.70% (5 y) (589 (OF10), 448.33 (OF5)) compared with the CK value (405), as did the number of pore throats by 188.30% (10 y) and 63.16% (5 y) (1880.67 (OF10), 1064.33 (OF5)) compared with the CK value (652.33). The average pore throat length decreased by 24.21% (10 y) and 9.85% (5 y) (2975.32 (OF10), 3539.43 (OF5)) compared with the CK value (3926.04).

3.3. Correlating Soil Physical and Chemical Properties with Soil Aggregate and Pore Structure Parameters

A correlation analysis revealed the OM content and the 2−0.25 mm particle size aggregate mass percentage to be highly significantly and positively correlated with the MWD (p < 0.01) and highly significantly and negatively correlated with the <0.25 mm particle size aggregate mass percent (p < 0.01); OM content and soil porosity were highly significantly positively correlated with soil porosity (p < 0.01) and positively correlated with soil connectivity. FD and the number of pore throat paths (p < 0.05) and URE and INV were significantly positively correlated with the mass percentage of aggregates in the 0–2 mm particle size class and the MWD (p < 0.01) (Table 4). Soil OM was significantly and positively correlated with total connectivity, FD, and the average pore throat number (Figure 4).

3.4. Effects of Fertilizer Use on Connected Pore Size Distribution

The number of pores in the soil increased by 45.43% (10 y) and 10.72% (5 y) following organic fertilizer application (Table 3). The proportion of connected pores of size 0–500 μm increased significantly after fertilizer application; the proportion of pores of 0–300 μm increased by 5.60% (10 y) and 5.23% (5 y), while that of 300–400 μm increased by 15.85% (10 y) and 14.46% (5 y) (Figure 5). This demonstrates that application of organic fertilizer increased the number of soil pores within the root zone and improved the soil structure. The pore throat is a narrow channel between connected pores, and its radius characterizes the size of the fluid migration channel (an indication of the difficulty of fluid infiltration). The number of pore throats increased after organic fertilizer application (Table 1), and the proportion of pore throats in the 500–1000 μm class also increased (Figure 6).

4. Discussion

4.1. Response of Soil to Long-Term Application of Organic Fertilizer

Ways to reduce the quantities of chemical fertilizers applied in agriculture have become a hot topic in contemporary research. Organic fertilizer provides nutrients needed for crop growth, and it is highly fertile and durable [16]. We examine the effects of application of organic fertilizers over a 10-year period. Because most nutrients in organic fertilizers are organic, the process of releasing inorganic nutrients to crops via their mineralization is slow [17]. Inter-root soil physicochemical properties indicate soil quality, which is generally defined as the ability of soil to maintain environmental quality and promote plant productivity. Dominant strategies for inter-root management include the regulation of root growth through tillage practices [18]. Long-term irrigation and fertilization regimes in date palm gardens jointly regulate the soil’s physicochemical properties in the root system. Long-term STI promotes shallow palm tree root growth, with an STI water source depth of ~25 cm; additionally, a fertilizer is applied at the same depth. We demonstrate that organic fertilizer application can increase soil OM, INV, and URE, with the effect on OM content being either direct or indirect (through crop growth). Soil OM is mainly derived from plant leaves, root secretion, and plant residue decomposition [19]. Therefore, organic fertilizer application can promote date palm growth, improve root secretion, concurrently improve the input of soil exogenous carbon, and promote total organic carbon conversion in soil [20].
Soil enzymes play an important role in soil nutrient cycling and metabolism processes [21]. Increased carbon and nitrogen sources for soil microorganisms favor microbial reproduction and stimulate increased enzyme activity [22]. Organic matter (a substratum for soil enzymes) may directly induce an increase in soil enzyme activity [23]. Rietz and Haynes [24] reported that small increases in conductivity have a highly destructive effect on soil microbial activity. Microbial colonization and carbon use efficiency are inhibited [25]. We report that soil BD and EC decreased after organic fertilizer application due to organic fertilizers increasing the soil porosity; however, at the same time, organic fertilizers can adsorb salts from the soil, similar to Ren [26]. The application of organic fertilizers in saline soils improves conditions for microorganisms by increasing soil carbon and nitrogen sources and reducing soil salinity, increasing the OM content of saline soils.
Soil aggregates are categorized into macroaggregates (particle size > 0.25 mm) and microaggregates (particle size < 0.25 mm) [27]. Water-stable aggregates characterize the structure and stability of soil; the higher the content of soil water-stable macroaggregates, the more stable the soil [28]. We report that the application of organic fertilizer does not significantly increase the proportion of aggregates > 2 mm but significantly increases the proportion of those from 0.25 to 2 mm. Organic carbon in macroaggregates is also susceptible to environmental influences and rapid turnover, indicating that macroaggregates provide no physical protection for organic carbon formation and growth, whereas microaggregates (2–0.25 mm) do have strong protective and cumulative effects that are conducive to carbon sequestration [29]. This indicates that the application of organic fertilizer improves soil aggregate stability by increasing exogenous organic carbon input and that higher aggregate stability increases the soil carbon storage capacity. High salinity is a key factor in regard to limiting soil aggregate formation and stability [30]. We report that the OM content correlates positively and significantly with the MWD (p < 0.01) and negatively with EC. Therefore, in saline soils, exogenous soil organic carbon inputs may be the main pathways in regard to organic carbon sequestration [31], and organic fertilizers can improve the structures of agglomerates by reducing soil salinity with increased carbon inputs.

4.2. Effect of Organic Fertilizers on Soil Connectivity Pore Space

The application of organic and inorganic fertilizers affects soil pore morphology, pore space distribution, and pore network structures within aggregates. Long-term application of organic fertilizers leads to accumulation of soil OM, which leads to the binding and cementation of soil aggregates within which pore systems form [32]. Soil pore structure responds to organic fertilizer mainly in terms of pore size ranges. Larger pore sizes facilitate water transport and material exchange and reduce stress generated by trapped air and volume changes in the pore system, thus improving aggregate stability [33]. Pore network connectivity is a key parameter of soil structure that affects plant growth and water and gas transportation. Soil pore connectivity also drives saturated soil hydraulic conductivity [34], air permeability [35], and greenhouse gas releases [36]. In this study, the distribution of soil pores was analyzed at a radius of 0–1000 μm. The characteristics of the soil pore structure of radius 5–1000 μm determine the properties of the soil microenvironment [37], and soil environment microheterogeneity affects the physical, chemical, and biological processes of soil carbon. Pagliai [38] reported that transport pores > 50 μm play an important role in soil–water–plant relationships. We report that soil porosity and connectivity are higher following organic fertilizer application and that the proportion of connected pores of 0–500 μm size increases significantly. We also report that an increase in the number of soil pores following 10 y of organic fertilizer application is accompanied by an increased number of pore throats, although the average length of these throats decreased. This is somewhat different from findings reported by Kandra [39], who concluded that organic fertilizer application improved soil pore structure by increasing the average pore throat and channel length. Any differences may be related to the subject of the study and soil conditions. Our study was based on connecting pore size distributions in sandy soils, which are uniformly more porous [40]. The higher growth in the number of pore throats following the application of organic fertilizers also promotes the creation of connecting channels between adjacent pores. Irregular pores are important for storage and the transport of soil water and gasses [38]. Greater connectivity and complexity in the pore system favor soil water movement and aeration [41]. Long-term application of organic fertilizers induces the connection of adjacent pores and facilitates solute transport between soil particles. Pagliai [38] reported a positive correlation between soil URE and the percentage of pores of radius 30–200 μm in pore-equivalent size. Soil pores with equivalent sizes of between 30 and 500 μm play the most important role in soil–water–plant relationships and in maintaining soil structure [42]. In our study conditions, the percentage of pores of 0–500 μm aperture was greatest after 10 y of organic fertilizer application, then 5 y, and it was lowest when no organic fertilizer had been applied. This indicates that organic fertilizer improves soil pore structure by increasing the percentage of pores of 0–500 μm aperture and significantly increases the percentage of 400–1000 μm pore throats.
Ct scanning technology still has a lot of room for research in the field of soil science, and, in the future, people can investigate the effects of different organic fertilizer types or the impact of climate change on soil properties. At the same time, we can also explore the potential benefits of organic fertilizer use in terms of improved crop yields, water use efficiency, and reduced environmental impact.

5. Conclusions

Long-term organic fertilizer application reduced soil bulk density and increased soil organic matter, enzyme activity, and aggregate stability. Based on fractal dimension morphological characteristics, the numbers of pore throats, pore connectivity, and soil pore structure became increasingly complex and stable over time. Soil porosity also increased with prolonged organic fertilizer application. Connected pore size distributions indicate that the application of organic fertilizer increased the proportion of connected pores with a radius of 0–500 μm to that of the number of pore throats with a radius of 500–1000 μm, improving soil pore structure by increasing the number of pores and pore throats. The long-term application of organic fertilizers can indirectly improve soil pore structure by decreasing soil salinity and increasing soil organic matter, and this effect is more significant with prolonged application. These results suggest that organic fertilizer can be a valuable tool for improving soil health and sustainable agriculture, particularly in arid and semi-arid regions.

Author Contributions

Conceptualization, methodology, formal analysis, investigation, software, writing—original draft preparation, H.Z.; conceptualization, methodology, resources, writing—review and editing, S.Z.; conceptualization, methodology, writing—review and editing, W.H.; conceptualization, methodology, Z.Z.; conceptualization, methodology, investigation, software, K.L.; and conceptualization, validation, resources, data curation, writing—review and editing, supervision, project administration, funding acquisition, S.S. All authors have read and agreed to the published version of the manuscript.

Funding

This research was supported by the National Natural Science Foundation of China (NO. 51869030), and the Science and Technology Program Project in Alar City, First Division (NO. 2022XX01).

Data Availability Statement

The data presented in this study are available on request from the corresponding author; due to policy and legal reasons, data are classified and not disclosed.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Xiang, X.; Liu, J.; Zhang, J.; Li, D.; Xu, C.; Kuzyakov, Y. Divergence in fungal abundance and community structure between soils under long-term mineral and organic fertilization. Soil Tillage Res. 2020, 196, 104491. [Google Scholar] [CrossRef]
  2. Zhu, J.; Peng, H.; Ji, X.; Li, C.; Li, S. Effects of reduced inorganic fertilization and rice straw recovery on soil enzyme activities and bacterial community in double-rice paddy soils. Eur. J. Soil. Biol. 2019, 94, 103116. [Google Scholar] [CrossRef]
  3. Guo, K.; Zhao, Y.; Liu, Y.; Chen, J.; Wu, Q.; Ruan, Y.; Li, S.; Shi, J.; Zhao, L.; Sun, X.; et al. Pyrolysis temperature of biochar affects ecoenzymatic stoichiometry and microbial nutrient-use efficiency in a bamboo forest soil. Geoderma 2020, 363, 114162. [Google Scholar] [CrossRef]
  4. Paul, B.K.; Vanlauwe, B.; Ayuke, F.; Gassner, A.; Hoogmoed, M.; Hurisso, T.T.; Koala, S.; Lelei, D.; Ndabamenye, T.; Six, J.; et al. Medium-term impact of tillage and residue management on soil aggregate stability, soil carbon and crop productivity. Agric. Ecosyst. Environ. 2013, 164, 14–22. [Google Scholar] [CrossRef]
  5. Rab, M.A.; Haling, R.E.; Aarons, S.R.; Mannah, M.; Young, I.M.; Gibson, D. Evaluation of X-ray computed tomography for quantifying macroporosity of loamy pasture soils. Geoderma 2014, 213, 460–470. [Google Scholar] [CrossRef]
  6. Kim, C.; Devegowda, D. Molecular dynamics study of fluid-fluid and solid-fluid interactions in mixed-wet shale pores. Fuel 2022, 319, 123587. [Google Scholar] [CrossRef]
  7. Lu, S.; Yu, X.; Zong, Y. Nano-microscale porosity and pore size distribution in aggregates of paddy soil as affected by long-term mineral and organic fertilization under rice-wheat cropping system. Soil Tillage Res. 2019, 186, 191–199. [Google Scholar] [CrossRef]
  8. Ananyeva, K.; Wang, W.; Smucker, A.; Rivers, M.L.; Kravchenko, A.N. Can intra-aggregate pore structures affect the aggregate’s effectiveness in protecting carbon? Soil Biol. Biochem. 2013, 57, 868–875. [Google Scholar] [CrossRef]
  9. Yudina, A.; Kuzyakov, Y. Dual nature of soil structure: The unity of aggregates and pores. Geoderma 2023, 434, 116478. [Google Scholar] [CrossRef]
  10. Fei, C.; Dong, Y.Q.; An, S.Z. Factors driving the biomass and species richness of desert plants in northern Xinjiang China. PLoS ONE 2022, 17, e0271575. [Google Scholar] [CrossRef]
  11. Xu, L.Y.; Wang, M.Y.; Shi, X.Z.; Yu, Q.B.; Shi, Y.J.; Xu, S.X.; Sun, W.X. Effect of long-term organic fertilization on the soil pore characteristics of greenhouse vegetable fields converted from rice-wheat rotation fields. Sci. Total Environ. 2018, 631, 1243–1250. [Google Scholar] [CrossRef] [PubMed]
  12. Wang, W.; Zhang, Y.; Li, H. Quantification of soil structure via synchrotron X-ray tomography after 22 years of fertilization. Eur. J. Soil Sci. 2021, 72, 2115–2127. [Google Scholar] [CrossRef]
  13. Dal Ferro, N.; Charrier, P.; Morari, F. Dual-scale micro-CT assessment of soil structure in a long-term fertilization experiment. Geoderma 2013, 204, 84–93. [Google Scholar] [CrossRef]
  14. Koestel, J.; Larsbo, M.; Jarvis, N. Scale and REV analyses for porosity and pore connectivity measures in undisturbed soil. Geoderma 2020, 366, 114206. [Google Scholar] [CrossRef]
  15. Kan, X.; Zheng, W.; Cheng, J.; Zhangzhong, L.; Li, J.; Liu, B.; Zhang, X. Investigating Soil Pore Network Connectivity in Varied Vegetation Types Using X-ray Tomography. Water 2023, 15, 3823. [Google Scholar] [CrossRef]
  16. Mancer, H.; Rouahna, H.; Souici, S.; Otmani, Z.; Bettiche, F.; Menasria, H.; Rechachi, M.Z.; Chaib, W.; Mostephaoui, T. Effects of mineral and organic fertilization on potato production in sandy soil in arid region. Sci. Afr. 2024, 23, e2112. [Google Scholar] [CrossRef]
  17. Xu, Y.; Liu, X.; Yan, L.; Huang, X.; Wang, J. The addition of organic fertilizer can reduce the dependence of dryland yield on rainfall-based on a 32-year long-term study. Sci. Total Environ. 2024, 915, 170152. [Google Scholar] [CrossRef]
  18. Zhang, F.; Shen, J.; Zhang, J.; Zuo, Y.; Li, L.; Chen, X. Rhizosphere processes and management for improving nutrient use efficiency and crop productivity: Implications for China. Adv. Agron. 2010, 107, 1–32. [Google Scholar] [CrossRef]
  19. Li, S.; Sheng, M.; Yuan, F.; Yin, J. Effect of land cover change on total SOC and soil PhytOC accumulation in the karst subtropical forest ecosystem, SW China. J. Soils Sediments 2021, 21, 2566–2577. [Google Scholar] [CrossRef]
  20. Luan, H.; Gao, W.; Huang, S.; Tang, J.; Li, M.; Zhang, H.; Chen, X.; Masiliūnas, D. Organic amendment increases soil respiration in a greenhouse vegetable production system through decreasing soil organic carbon recalcitrance and increasing carbon-degrading microbial activity. J. Soils Sediments 2020, 20, 2877–2892. [Google Scholar] [CrossRef]
  21. Xiao, L.; Huang, Y.; Zeng, Q.; Zhao, J.; Zhou, J. Soil enzyme activities and microbial biomass response to crop types on the terraces of the Loess Plateau, China. J. Soils Sediments 2018, 18, 1971–1980. [Google Scholar] [CrossRef]
  22. Li, Q.; Zhang, D.; Cheng, H.; Ren, L.; Jin, X.; Fang, W.; Yan, D.; Li, Y.; Wang, Q.; Cao, A. Organic fertilizers activate soil enzyme activities and promote the recovery of soil beneficial microorganisms after dazomet fumigation. J. Environ. Manag. 2022, 309, 114666. [Google Scholar] [CrossRef] [PubMed]
  23. Błońska, E.; Piaszczyk, W.; Staszel, K.; Lasota, J. Enzymatic activity of soils and soil organic matter stabilization as an effect of components released from the decomposition of litter. Appl. Soil Ecol. 2021, 157, 103723. [Google Scholar] [CrossRef]
  24. Rietz, D.N.; Haynes, R.J. Effects of irrigation-induced salinity and sodicity on soil microbial activity. Soil Biol. Biochem. 2003, 35, 845–854. [Google Scholar] [CrossRef]
  25. Xie, W.; Zhang, Y.; Li, J.; Wei, S.; Li, X.; Yu, H.; Guan, B. Straw application coupled with N and P supply enhanced microbial biomass, enzymatic activity, and carbon use efficiency in saline soil. Appl. Soil Ecol. 2021, 168, 104128. [Google Scholar] [CrossRef]
  26. Ren, J.; Liu, X.; Yang, W.; Yang, X.; Li, W.; Xia, Q.; Li, J.; Gao, Z.; Yang, Z. Rhizosphere soil properties, microbial community, and enzyme activities: Short-term responses to partial substitution of chemical fertilizer with organic manure. J. Environ. Manag. 2021, 299, 113650. [Google Scholar] [CrossRef]
  27. Elliott, E. Aggregate structure and carbon, nitrogen, and phosphorus in native and cultivated soils. Soil Sci. Soc. Am. J. 1986, 50, 627–633. [Google Scholar] [CrossRef]
  28. Zuo, F.; Li, X.; Yang, X.; Wang, Y.; Ma, Y.; Huang, Y.; Wei, C. Soil particle-size distribution and aggregate stability of new reconstructed purple soil affected by soil erosion in overland flow. J. Soils Sediments 2020, 20, 272–283. [Google Scholar] [CrossRef]
  29. Nottingham, A.T.; Griffiths, H.; Chamberlain, P.M.; Stott, A.W.; Tanner, E.J. Soil priming by sugar and leaf-litter substrates: A link to microbial groups. Appl. Soil Ecol. 2009, 42, 183–190. [Google Scholar] [CrossRef]
  30. Xie, W.; Shao, P.; Zhang, Y.; Wei, S.; Li, J.; Sun, Y.; Zhang, H. Saline soil organic matter characteristics of aggregate size fractions after amelioration through straw and nitrogen addition. Land. Degrad. Dev. 2023, 34, 2098–2109. [Google Scholar] [CrossRef]
  31. Xiang, J.; Shi, W.; Jing, Z.; Guan, Y.; Yang, F.; Wang, G.; Sun, X.; Li, J.; Li, Q.; Zhang, H. Exogenous calcium-induced carbonate formation to increase carbon sequestration in coastal saline-alkali soil. Sci. Total Environ. 2024, 946, 174338. [Google Scholar] [CrossRef] [PubMed]
  32. Zhou, H.; Fang, H.; Mooney, S.J.; Peng, X. Effects of long-term inorganic and organic fertilizations on the soil micro and macro structures of rice paddies. Geoderma 2016, 266, 66–74. [Google Scholar] [CrossRef]
  33. Naveed, M.; Moldrup, P.; Vogel, H.; Lamandé, M.; Wildenschild, D.; Tuller, M.; Jonge L., W. Impact of long-term fertilization practice on soil structure evolution. Geoderma 2014, 217, 181–189. [Google Scholar] [CrossRef]
  34. Sandin, M.; Koestel, J.; Jarvis, N.; Larsbo, M. Post-tillage evolution of structural pore space and saturated and near-saturated hydraulic conductivity in a clay loam soil. Soil Tillage Res. 2017, 165, 161–168. [Google Scholar] [CrossRef]
  35. Paradelo, M.; Katuwal, S.; Moldrup, P.; Norgaard, T.; Herath, L.; Jonge, L.W. X-ray CT-derived soil characteristics explain varying air, water, and solute transport properties across a loamy field. Vadose Zone J. 2016, 15, 1–13. [Google Scholar] [CrossRef]
  36. Rabot, E.; Lacoste, M.; Hénault, C.; Cousin. Using X-ray computed tomography to describe the dynamics of nitrous oxide emissions during soil drying. Vadose Zone J. 2015, 14, 1–10. [Google Scholar] [CrossRef]
  37. Kravchenko, A.N.; Guber, A.K. Soil pores and their contributions to soil carbon processes. Geoderma 2017, 287, 31–39. [Google Scholar] [CrossRef]
  38. Pagliai, M.; Vignozzi, N.; Pellegrini, S. Soil structure and the effect of management practices. Soil Tillage Res. 2004, 79, 131–143. [Google Scholar] [CrossRef]
  39. Kandra, B.; Tall, A.; Vitková, J.; Procházka, M.; Šurda, P. Effect of Humic Amendment on Selected Hydrophysical Properties of Sandy and Clayey Soils. Water 2024, 16, 1338. [Google Scholar] [CrossRef]
  40. Prifling, B.; Weber, M.; Ray, N.; Prechtel, A.; Phalempin, M.; Schlüter, S.; Vetterlein, D.; Schmidt, V. Quantifying the impact of 3D pore space morphology on soil gas diffusion in loam and sand. Transp. Porous Med. 2023, 149, 501–527. [Google Scholar] [CrossRef]
  41. Regelink, I.C.; Stoof, C.R.; Rousseva, S.; Weng, L.; Lair, G.J.; Kram, P.; Nikolaidis, N.P.; Kercheva, M.; Banwart, S.; Comans, R.N. Linkages between aggregate formation, porosity and soil chemical properties. Geoderma 2015, 247, 24–37. [Google Scholar] [CrossRef]
  42. Pagliai, M.; De Nobili, M. Relationships between soil porosity, root development and soil enzyme activity in cultivated soils. In Soil Structure/Soil Biota Interrelationships; Elsevier: Amsterdam, The Netherlands, 1993; pp. 243–256. [Google Scholar] [CrossRef]
Agronomy 14 02964 g001
Figure 1. Schematic of sand tube irrigation system (left) and soil collection (right).
Figure 1. Schematic of sand tube irrigation system (left) and soil collection (right).
Agronomy 14 02964 g001
Agronomy 14 02964 g002
Figure 2. Three-dimensional reconstruction of connected pore networks in soil under different fertilizer treatments. OF10 (10 y), OF5 (5 y), CK (none).
Figure 2. Three-dimensional reconstruction of connected pore networks in soil under different fertilizer treatments. OF10 (10 y), OF5 (5 y), CK (none).
Agronomy 14 02964 g002
Agronomy 14 02964 g003
Figure 3. Pore ball-and-stick network model of reconstructed soil columns using X-ray CT data. Inner colors represent different soil pore volumes (the larger the pore the darker the color). OF10 (10 y), OF5 (5 y), CK (none).
Figure 3. Pore ball-and-stick network model of reconstructed soil columns using X-ray CT data. Inner colors represent different soil pore volumes (the larger the pore the darker the color). OF10 (10 y), OF5 (5 y), CK (none).
Agronomy 14 02964 g003
Agronomy 14 02964 g004
Figure 4. Linear regressions between OM and total porosity, fractal dimension (FD), total connectivity, and average throat number. Note: OM, soil organic matter; FD, fractal dimension.
Figure 4. Linear regressions between OM and total porosity, fractal dimension (FD), total connectivity, and average throat number. Note: OM, soil organic matter; FD, fractal dimension.
Agronomy 14 02964 g004
Agronomy 14 02964 g005
Figure 5. Connected pore size distribution based on the three-dimensional model. OF10 (10 y), OF5 (5 y), CK (none).
Figure 5. Connected pore size distribution based on the three-dimensional model. OF10 (10 y), OF5 (5 y), CK (none).
Agronomy 14 02964 g005
Agronomy 14 02964 g006
Figure 6. Equivalent radius of connected pore throats based on a connected pore ball-and-stick network model. OF10 (10 y), OF5 (5 y), CK (none).
Figure 6. Equivalent radius of connected pore throats based on a connected pore ball-and-stick network model. OF10 (10 y), OF5 (5 y), CK (none).
Agronomy 14 02964 g006
Table 1. Comparison of soil physical and chemical properties following organic fertilization.
Table 1. Comparison of soil physical and chemical properties following organic fertilization.
ParameterOF10OF5CK
BD (g·cm−3)1.37 b1.40 ab1.41 a
EC (μs·cm−1)118.17 c166.04 b191.73 a
OM (g·kg−1)9.52 a7.69 a7.58 a
INV (mg·g−1·d−1)3.96 a3.37 b3.01 b
URE (mg·g−1·d−1)1065.26 a850.47 a782.39 a
Note: OF10 (10 y), OF5 (5 y), CK (none). BD, soil bulk density; EC, soil electrical conductivity; OM, soil organic matter; INV, soil sucrase activity; URE, soil urease activity. Different letters in the table indicate significant differences between treatments at the p < 0.05 level.
Table 2. Soil aggregate composition following organic fertilizer application.
Table 2. Soil aggregate composition following organic fertilizer application.
ParameterOF10OF5CK
>2 mm (%)2.66 a2.83 a2.67 a
2–0.25 mm (%)34.49 a26.95 ab22.64 b
<0.25 mm (%)62.85 b70.22 ab74.69 a
MWD (mm)0.52 a0.45 ab0.40 b
Note: OF10 (10 y), OF5 (5 y), CK (none); >2 mm (mass percentage of aggregates of diameter > 2 mm in soil), 2–0.25 mm (mass percentage of aggregates of diameter 2–0.25 mm in soil), <0.25 mm (mass percentage of aggregates of diameter < 0.25 mm in soil); MWD (mean weight diameter). Different letters in the table indicate significant differences between treatments at the p < 0.05 level.
Table 3. Soil pore network parameters following the application of organic fertilizer.
Table 3. Soil pore network parameters following the application of organic fertilizer.
Pore PropertiesOF10OF5CK
Total porosity (%)15.51 a9.44 b8.62 b
Total connectivity (%)83.02 a63.07 a61.60 a
Fractal dimension2.62 a2.60 b2.57 b
Average pore number589.00 a448.33 a405.00 a
Average pore throat number1880.67 a1064.33 a652.33 a
Average pore throat length (μm)2975.32 b3539.43 a3926.04 a
Note: OF10 (10 y), OF5 (5 y), CK (none). Different letters in the table indicate significant differences between treatments at the p < 0.05 level.
Table 4. Correlations between soil physicochemical properties and soil aggregate and pore structure parameters.
Table 4. Correlations between soil physicochemical properties and soil aggregate and pore structure parameters.
Soil Core PropertiesBDECOMINVURE
>2 mm (%)−0.0510.009−0.251−0.4100.001
2–0.25 mm (%)−0.803−0.7320.986 **0.977 **0.951 **
<0.25 mm (%)0.827 *0.748−0.980 **0.952 **0.973 **
MWD (mm)−0.826 *−0.7270.970 **0.924 **0.984 **
Total porosity (%)−0.922 **−0.825 *0.952 **0.949 **0.935 **
Total connectivity (%)−0.876 *−0.7290.853 *0.876 *0.764
Fractal dimension−0.905 *−0.816 *0.877 *0.875 *0.901 *
Pore number−0.610−0.5180.1080.1030.168
Average throat number−0.713−0.5820.833 *0.7170.875 *
Average channel length (μm)0.8010.908 *−0.596−0.628−0.572
Note: OF10 (10 y), OF5 (5 y), CK (none). BD, soil bulk density; EC, soil electrical conductivity; OM, soil organic matter; INV, soil sucrase activity; URE, soil urease activity, >2 mm (mass percentage of aggregates of diameter >2 mm in soil), 2–0.25 mm (mass percentage of aggregates of diameter 2–0.25 mm in soil), < 0.25 mm (mass percentage of aggregates of diameter < 0.25 mm in soil); MWD (mean weight diameter). Mean values were tested using Fisher’s least significant difference (LSD) at p < 0.05 (*) or p < 0.01 (**).
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Zhang, H.; Zhou, S.; Huang, W.; Zhu, Z.; Li, K.; Sun, S. Long-Term Application of an Oil Residue Organic Fertilizer Improved Soil Physical Properties in the Root Zone of Jujube Trees. Agronomy 2024, 14, 2964. https://doi.org/10.3390/agronomy14122964

AMA Style

Zhang H, Zhou S, Huang W, Zhu Z, Li K, Sun S. Long-Term Application of an Oil Residue Organic Fertilizer Improved Soil Physical Properties in the Root Zone of Jujube Trees. Agronomy. 2024; 14(12):2964. https://doi.org/10.3390/agronomy14122964

Chicago/Turabian Style

Zhang, Huadong, Shaoliang Zhou, Weixiong Huang, Zhu Zhu, Kaixuan Li, and Sanmin Sun. 2024. "Long-Term Application of an Oil Residue Organic Fertilizer Improved Soil Physical Properties in the Root Zone of Jujube Trees" Agronomy 14, no. 12: 2964. https://doi.org/10.3390/agronomy14122964

APA Style

Zhang, H., Zhou, S., Huang, W., Zhu, Z., Li, K., & Sun, S. (2024). Long-Term Application of an Oil Residue Organic Fertilizer Improved Soil Physical Properties in the Root Zone of Jujube Trees. Agronomy, 14(12), 2964. https://doi.org/10.3390/agronomy14122964

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop