Next Article in Journal
Identification and Evaluation of Diterpenoids from Glandular Trichome Secretions of Air/Sun-Cured Tobacco Germplasm Resources
Previous Article in Journal
The Impact of Bud Load on Berry Quality, Yield, and Cluster Compactness in H4 Strain Grapevines
Previous Article in Special Issue
Quantitative and Qualitative Traits of Duckweed (Lemna minor) Produced on Growth Media with Pig Slurry
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Agronomy
Volume 13
Issue 9
10.3390/agronomy13092432
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 thumb_up
...
Endorse textsms
...
Comment
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Soil Habitats Are Affected by Fungal Waste Recycling on Farmland in Agro-Pastoral Ecotone in Northern China

by
Feiyan Zhao
,
Shiling Shi
,
Ruibing Meng
,
Ze Ma
and
Zhongju Meng
*
College of Desert Control Science and Engineering, Inner Mongolia Agricultural University, Hohhot 010018, China
*
Author to whom correspondence should be addressed.
Agronomy 2023, 13(9), 2432; https://doi.org/10.3390/agronomy13092432
Submission received: 12 June 2023 / Revised: 18 August 2023 / Accepted: 14 September 2023 / Published: 21 September 2023
(This article belongs to the Special Issue Agricultural Waste Management in a Circular Economy Perspective)
Browse Figures
Review Reports Versions Notes

Abstract

:
As part of the ecological barrier and an essential element of food security, the agro-pastoral ecotone is vital in northern China. Since soil fertility in northern China is low due to frequent surface disturbances, it is necessary to improve the properties of the soil. This study aims to examine the impact of fungal residue return on soil properties based on six treatments (CK: 0 kg/40 m2; R3: 90 kg/40 m2; R5: 150 kg/40 m2; R7: 210 kg/40 m2; R9: 270 kg/40 m2; R11: 330 kg/40 m2;) of fungal residue return concentration experimental data from 0 to 30 cm soil depth. The results showed that the effect of fungal residue returning on soil habits was greater at 0–10 cm of the surface layer. The bulk density can be reduced to 25.83% of CK, and water content can be increased up to 26.26%. Adding fungal residue to the field led to a greater increase in soil parameters (SOM and AP), and this characteristic effect continued as the return concentration increased. The number of soil bacteria and actinomycetes remained stable, and the amount of fungi was at its lowest. Compared with CK, the number of bacteria, fungi, and actinomycetes increased by 1.94 times, 1.46 times, and 1.71 times, respectively. After the residue was returned to the field, AK had the strongest correlation with other factors (p < 0.01), and microorganism and enzyme activities were strongly correlated (p < 0.01). In conclusion, this study presents a new method of resource utilization of downstream wastes in the food industry while simultaneously providing natural, pollution-free improvements to the soil, which is very beneficial to increasing crop yield.

1. Introduction

Northern China’s agro-pastoral ecotone is a fragile ecosystem prone to environmental degradation [1,2,3] and is a transitional type between arid and semi-arid climates [4]. Many agro-pastoral ecotones face survival and developmental challenges, such as overgrazing, over-cultivation, and overcutting, due to rapid population growth. These regions may experience severe desertification that affects the development of the regional economy and society as a whole [5,6,7]. The central and western parts of Inner Mongolia are the core areas of the agro-pastoral ecotone in northern China. Five cities, including Hohhot, Baotou, Ordos, Ulanqab, and Bayannur, cover an area of about 250,600 km2, including Wuchuan County [8]. The region uses the characteristics of the farming–pastoral junction to form a commodity grain base whilst also protecting the ecological beauty of Hohhot, the capital of Inner Mongolia. This ecotone is pivotal for ecological security, social stability, and economic development as it is an economic link between an agricultural zone and a pastoral area. Wuchuan County of Hohhot City experiences the wind erosion and desertification of the northern foothill of Yinshan. The poor soil, arid climate, and other natural factors in the region, in addition to the low level of agricultural production, coupled with increasing population pressures, increased storage capacity, and improper management, create threats of poverty and desertification in this region. There is an urgent need for reasonable methods to improve productivity in order to meet both food security needs and achieve sustainable development. Nevertheless, excessive fertilization is common in this situation [9,10]; thus, it is necessary to reduce fertilizer application, promote adequate supplies of food and other agricultural products, and achieve sustainable rural development are necessary.
As an efficient and reasonable renewable resource, straw resources are used to satisfy China’s economic growth demand (by saving scarce natural resources); however, they also serve as a basis for environmental protection and social sustainability in the country [11]. Straw-return technology is more mature than that of fungal residue-return. Fungal residue is the remaining medium waste that remains after the cultivation and harvest of edible fungi; this is an inorganic, nutrient-rich material with high porosity [12,13]. China’s edible fungi industry is well developed, with edible fungi production reaching 40.614 million tons of edible fungi produced in 2020; assuming that the average amount of mushroom dregs is about five times that of the edible fungi, this amounts to about 200 million tons of mushroom dregs [14]. Many domestic slag treatments for natural stacking or burning waste resources result in environmental pollution. Many reports have demonstrated the advantages of mushroom dregs as a supplement for fertilizers. Meng et al. [15] determined whether composts containing fungal residues and pig manure can positively affect N, p, and K values. Studies have reported that the mushroom residue that remains after the cultivation of mushroom bran is rich in numerous bacterial proteins, lignin, and various nutrients, providing a good source of organic fertilizer and soil amendment [16,17]. The treatment of edible fungus cultivation waste as organic fertilizer can not only improve soil fertility but also reduce environmental pollution, forming a positive cycle for the agricultural ecosystem. At the same time, it also reduces the number of bacteria in the cultivation environment of edible fungi and promotes the healthy and sustainable development of the edible fungi industry [18].
Changes in soil fertility may affect nutrient cycling. Microorganisms are the most dynamic part of the soil ecosystem; soil microbial populations serve as an index of soil fertility, as they are essential to soil biochemical activity and nutrient transformation and utilization [19,20]. Their functions are carried out by soil enzymes, which control the direction and intensity of biochemical reactions. Fungal residue improves organic carbon and sucrase activity, enhances bacteria diversity, and changes the dominant flora [21]. And when it is residue returned to the farmland, it can significantly affect urease activity and increase the number of fungi, bacteria, and actinomycetes [22]. Other studies have demonstrated that the application of mushroom residue significantly increased soil urease activity and the number of actinomycetes and fungi [23]. Based on this, it is essential to consider the application of mushroom residue from the perspective of different soil properties.
Therefore, mixed application of animal manure and mushroom residue can enrich the utilization of waste fungal residue. The objectives of this study were to compare the effects of different treatments of residue management on soil contents and the correlation between the soil’s physical and chemical properties and microbial quantity and enzyme activity that efficiently provide references for the efficient organic agriculture use of residues.

2. Materials and Methods

2.1. Study Area

We conducted a field experiment in Wu Chuan County (40°47′~41°23′ N, 110°31′~111°53′ E) in Hohhot, northern China. This area lies at the northern foot of Yinshan Mountain in a pastoral ecotone. The area falls within the temperate zone of continental climate. With an average temperature of 3.0 °C, it receives an average rain of 360 mm a year, mostly falling from July to August. The most common soil type is chestnut soil. The major crops are potato (Solanum tuberosum), naked oats (Avena sativa), and buckwheat (Fagopyrum esculentum) [24].

2.2. Experimental Design and Field Management

In this study, all experiments were carried out in the Inner Mongolia Agricultural University long-term dry farmland experimental base and were mainly focused on the observation of plant growth and development and water and fertilizer conservation in dry farmlands. The geographical features and climatic factors were consistent. The soil type used within the study site is chestnut soil, and the soil in this area has been threatened by wind erosion and salinization for a long time. As shown in Table 1, the soil fertility was maintained at a low level.
The experimental materials were soil amendments formed via the co-fermentation of a large amount of discarded fungal residue (nitrogen: 1.5–2%, phosphorus: 0.5–0.8%, potassium: 1.5–2%, and organic matter comprised 30–40%) and organic fertilizer (cow manure, organic matter: 15–25%.) around the sample plot. Before it was returned to the field, the fermented fungal residue was packed into packaging bags for easy transportation (30 per package). The amount returned to the field was determined at 6 gradient levels based on the previous pre-experiment was determined (CK/R3/R5/R7/R9/R11; CK was used as the control. Each returning concentration was set with 5 replicates, and the specific returning amount is shown in Table 2. The experiment followed the block design, and the amount of returning farmland was randomly distributed. The area of the plot was 40 m2 (4 m × 10 m). To prevent permeable lateral flow, 0.5 m wide ridges were built between adjacent plots with no marginal effect. The experiment was carried out during the spring tillage period (May) of 2019. The residue was laid on the surface and rotary tilled to 0–30 cm, and the naked oats with good local adaptability were planted for three consecutive years. The seeds were sown in drills, with row spacing of 15–20 cm [25]. After harvesting the plant parts were harvested in early September 2022, soil sampling was performed. The experimental sampling points have been reserved. According to the growth characteristics of crops, no irrigation treatment was carried out, but weeds were removed during the growth period. For protection against pests and diseases, chemical agents with less impact on crops were used. There were no other factors that interfered with the experiment (Figure 1).

2.3. Collection and Determination of Soil Samples

The experimental sampling was carried out under the condition that no precipitation event occurred within one week of plant harvest. The 0–30 cm soil layer (divided into 0–10 cm, 10–20 cm, and 20–30 cm layers) was randomly sampled and mixed in each unit according to the 5-point sampling method, using a 100 cm3 ring knife to determine of the soil’s physical properties. We removed all residues of plants and residues found in the soil samples. We then mixed the topsoil evenly and divided it into two parts, which were then sealed in equal amounts in plastic bags. To determine the soil’s chemical properties, one part of the soil was naturally air-dried, while the other part was stored in a refrigerator at 4 °C for subsequent microbial and enzymatic activity measurement. Soil bulk density (SBD), soil porosity (SP), and soil water content (SWC) were determined using the ring knife gravimetric method; soil organic matter (SOM) was determined using the potassium dichromate volumetric method and the external heating method; alkaline hydrolysis nitrogen (AN) was determined using the Conway diffusion dish method; alkaline phosphorus (AP) was determined using the Mo-Sb colorimetry, and quantified via spectrophotometry; alkaline pootassium (AK) was determined using a flame photometer [25]. Three soil enzymes were selected, including soil sucrase (SS), urease (SU), and acid phosphatase (SAP). The culture mediums of bacteria, fungi, and actinomycetes were NA, PDA, and CSA, respectively. The fungi, bacteria, and actinomyces were measured by plate colony counting [26]. Several soil samples were mixed, and one gram of suspension (dry weight equivalent) was prepared in 10 mL of water. This soil suspension was serially diluted (10−2, 10−3, and 10−4) using modified Gao’s No. 1 medium for bacteria, potato–sucrose medium for fungi, and medium for actinomycetes [27]. The samples were cultured (2 d for bacteria, 3 d for fungi, and 5 d for actinomycetes) in an incubator at 30 °C. Sucrase activity was determined using 3,5-dinitro salicylic acid colorimetric analysis; urease activity was determined using phenol–sodium hypochlorite coloration; acid phosphatase activity was measured using the triphenylphosphonium-4-amino-antipyrine colorimetric method, in which three duplicates were tested [28].
(1)
SBD
SBD   ( g / cm 3 ) = W 1 − W 0 V
where V is the ring knife volume (cm3); W1 is the weight of the soil + ring knife after drying (g); and W0 is the ring knife weight (g).
(2)
SP
SP ( % ) = ( W 2 − W 1 v ) × 100 %
where V is the ring knife volume (cm3); W2 is the water-saturated soil + ring knife weight (g); and W1 is the weight of soil + ring knife after drying (g).
(3)
SWC
SWC ( % ) = W 3 − W 1 W 1 × 100 %
where W3 is the weight of the wet soil just taken by the ring knife (g), and W1 is the weight of soil + ring knife after drying (g).

2.4. Data Calculations and Analysis

Using Excel 2019 and SPSS 25.0, the experimental data were processed and statistically analyzed. Origin2022b, a software package for rendering images, was used for image processing. The analysis of variance was performed using the one-way ANOVA and the LSD method to determine whether the differences between the treatments were statistically significant. A correlation analysis was carried out to test for a relationship. The tables were created using the Excel 2019 software.

3. Results

3.1. Effects of Fungal Residue Return on Soil Physical Properties

It has been shown that fungal residue can improve soil quality by influencing the physical properties of bulk density and the porosity of soil. Following the application of fungal residue, the soil’s physical properties were found to be improved (Table 3). The physical properties of the different soil layers under different treatments were the same. As the return concentration increased, the bulk density of the soil also changed accordingly. Specifically, the fungal residues promoted a reduction in the bulk density of the soil and were lower than that of CK, while the bulk density of the soil generally increased with the depth of the soil. The difference in SBD among different treatments was most significant in the 0–10 cm soil depth layer; in addition, porosity was increased by up to 12.12%, water content was increased by up to 26.26%, and bulk density was reduced by up to 25.83%. Different treatments had a hierarchical effect on the soil’s physical properties after residue return, and the soil porosity and soil water content were significantly higher in the 0–10 cm and 10–20 cm soil layers than in the 20–30 cm soil layers (p < 0.05). The soil porosity and soil water content of different treatments were arranged as follows: R11 > R9 > R7 > R5 > R3 > CK, the soil porosity of R11 was higher than other treatments, reaching 45.67%. The soil bulk density content was CK > R3 > R5 > R7 > R9 > R11, with similar trends in the 0–20 cm soil layer and no apparent regularity observed in the 0–30 cm layer, which had the minimum value of 1.12 g/cm3. In the 0–10 cm and 20–30 cm soil layers, the bulk density of the soil in R7 was significantly lower than that of the other treatments (p < 0.05), while the bulk density of the soil in R5 was substantially higher than that in R7 in the 10–20 cm soil layer. There was a significant difference in the soil porosity of R9 in the 0–10 cm and 10-20 cm soil layers (p < 0.05); however, the soil water content in the 20–30 cm soil layer did not differ significantly from those of the other treatments (p < 0.05).

3.2. Effects of Fungal Residue Return on Soil Chemical Properties

With the change in the soil physical properties, the soil chemical properties are also improved (Figure 2). The soil chemical properties also increased to varying degrees in response to different treatments, except for soil AN and AK. With the increase in return concentration, AN first decreased and then increased, while AK first increased and then decreased. When treated with fungal residue (p < 0.05), the soil AP content was significantly higher than observed when treated with CK, increasing from 2.4–4.4 mg/kg to 4.0–13.6 mg/kg. As the chemical content of the soil varied between the different treatments, there was a hierarchical pattern in the distribution. The chemical content of the soil was enriched in the 0–10 cm layer, reflecting the surface enrichment effect in terms of nutrient content. In the different soil layers, the soil chemical composition of each treatment showed additional variability depending on the treatment. Generally, in the 0–10 cm soil layer, the order of the individual chemical contents was roughly R11 > R9 > R7 > R5 > R3 > CK, while in the 10–20 cm and 20–30 cm soil layers, the trend was slightly different. The SOM of the soil layer increased by 35.33–45.64% in comparison to those of CK, while the AN increased by 58.06–78.33%. The average SOM values were 17.21 g/kg, 17.32 g/kg, and 15.87 g/kg in the 0–10 cm, 10–20 cm, and 20–30 cm layers, respectively. The average AN values were 66.75 mg/kg, 63.18 mg/kg, and 59.44 mg/kg in the 0–10 cm, 10–20 cm, and 20–30 cm layers, respectively. The soil AP in the 0–10 cm soil layer ranged from 4.4 mg/kg to 13.6 mg/kg. The AP content of the 10–20 cm soil layer varied from 3.7 mg/kg to 6.7 mg/kg. The AP content of the 20–30 cm soil layer changed from 2.4 mg/kg to 4.0 mg/kg.

3.3. Effects of Returning Fungus Residue on Microbial Quantity

With the increase in return concentration, the amount of bacteria and actinomycetes first increased and then decreased, and the amount of fungi showed a continuous increase (Table 4). Of the three microorganisms, the amount of fungi was the lowest. Under different concentrations of mushroom residue return, the proportion of bacteria was 58.13–61.39%; the proportion of fungi was 0.75–1.00%; and actinomycetes accounted for 37.82–40.8%. The number of bacteria and actinomycetes observed after the R9 treatment increased by 1.96 and 1.76 times, respectively, compared with CK, and the number of fungi increased by 1.45 times at the R11 concentration.
Treatment with fungal residue significantly increased the number of bacteria, fungi, and actinomycetes compared with CK (Figure 3). Meanwhile, the number of actinomycetes fungal residue returns significantly increased microbe numbers only in the 0–10 cm and 10–20 cm layers. The R7 treatment significantly increased the number of bacteria and fungi in the 0–10 cm layer. However, there was no significant difference between the 10–20 cm and the 20–30 cm layers. The microbial content was highest in R9 and R11. Neither the 10–20 cm nor 20–30 cm concentrations showed significant differences in the number of actinomycetes. It was found that the number of bacteria did not differ significantly between R3 and R5, but it was substantially higher in R7, R9, and R11 for all layers. The amount of aboveground fungi showed a similar trend to the changes in bacterial counts in the 0–10 cm layer.

3.4. Effects of Returning Fungus Residue on Enzyme Activity

Soil urease (SU), soil sucrase (SS), and soil alkaline phosphatase(SAP) were selected to characterize the effect of fungal residue inputs on soil enzymes(Figure 4). The activities of soil urease and soil sucrase decreased with the increasing soil depth, but soil alkaline phosphatase showed a trend of first decreasing and then increasing with depth. In the soils under fungal residue treatment, the soil enzyme activities were superior to those of CK, and the activities of SU, SS, and SAP increased to 4–49%, 3–63%, and 3–77%, respectively. The 0–10 cm layer activities were similar except for R9, for which there was a slight decrease in the enzyme activity of SAP, while those of R11 were close to the CK values. The SS activity had lower values in 20–30 cm compared to the other layers, reaching the lowest value of 11.49 g/d/g in the CK treatment. In terms of the maximum enzyme activity of SU at different layers, values above 73.62 mg/d/g were recorded at R11, while a lower value of 43.93 mg/d/g was obtained in CK. In the 0–30 cm soil layer, SS activity was characterized by R11 > R9 > R7 > R5 > R3 > CK; in the 0–10 cm soil layer, SU activity was represented by R9 > R7 > R5 > R3 > R11 > CK; in the 10–20 cm soil layer, SU activity was characterized by R7 > R9 > R11 > R5 > R3 > CK; in the 20–30 cm soil layer, SU activity was represented by R9 > R11 > R7 > R5 > R3 > CK. SAP activity first increased and then decreased with increasing return in the same soil layer.

3.5. Relationship between Soil Factors

Soil nutrients are an important indicator of soil fertility and also affect the growth and development of plants and the activity of soil microorganisms. The soil factors interacted with each other (Figure 5). The SBD was negatively correlated with the other parameters. Furthermore, SBD was significantly negatively correlated with SAP and SWC (p < 0.05). SWC was not strongly correlated with SAP, SS, Fungi, and Actinomycetes. The positive correlations between various chemical properties are very strong, showing the same amount of bacteria and SU. Bacterial content was positively correlated with SAP (p < 0.05) and significantly positively correlated with fungi, Actinomycetes, SS, and SU (p < 0.01). Fungi content was significantly positively correlated with Actinomycetes, SS, and SU (p < 0.01), but the correlation with SAP was weak. Actinomycetes counts were significantly positively correlated with SS, SU, and SAP (p < 0.01). SU was significantly positively correlated with SS (p < 0.01), but the correlation with SAP was weak. SS was significantly positively correlated with SAP (p < 0.01). AP and bacteria content were correlated with other soil factors, and the correlations between bacteria and other factors were stronger. SAP was only correlated with SBD, AP, bacteria, actinomycetes, and SS. SWC and AN had no correlation with SAP, SS, actinomycetes, and fungi.

4. Discussion

Soil productivity assessment is a sensitive indicator of the impact of treatments on soil processes, representing the potential of soil in agroecosystems. Fungal residue has a similar principle of action to straw after returning to the field. Straw is integrated into the soil using tilling methods, and the physical and chemical properties of the soil will be deeply affected. Adding fungal residue to soil will inevitably affect the soil’s organic matter, which influences a wide range of physical, chemical, and biological properties of soils [29]. In the experiment, the increase of fungal residues is effective in increasing the content of soil organic matter. Fungal residue has the characteristics of a low bulk density and high porosity, and returning it to the soil has been shown to reduce the soil bulk density, increase soil porosity, and improve soil aeration and water retention characteristics [30,31]. Our results showed that the soil bulk density of different return treatments decreased by 10.69–25.83%. Previous studies have shown that returning mushroom residue return to fields will increase soil organic matter content [32]. In this experimental study, it was concluded that organic matter increased with the increase in the concentration of mushroom residue returned to the field. This is inconsistent with the research conclusion of Gregorich et al. [33,34]. The reason for this conclusion may be that the amount of mushroom residue returned to the field was different from the type of soil, and therefore, the soil micro-ecological cycle differed in differences, and hence, the organic matter showed a continuous increase. Nitrogen, phosphorus, and potassium are essential nutrients for plant growth and development [35]. Wang et al. found that the application of organic fertilizer to soil can improve the nitrogen supply capacity of the soil [36]. In this study, the alkali-hydrolyzable nitrogen showed a trend of first decreasing and then increasing with the increase in residue concentration, probably because the consumption rate of the alkali-hydrolyzable was greater than the mineralization degree of the fungal residue [37]. In both the R9 and R11 treatments, the available hydrolysis nitrogen content was significantly higher than that in the control (p < 0.05). The soil available nitrogen contents in the R3 and R5 treatments were lower than the control, which may be related to factors such as tillage methods and cultivated crop types, but the specific mechanism behind this requires further study. Our results showed that a small decrease in available N was found in the R3 and R5 treatment compared to that in the CK treatment on the 0–30 cm soil layer. This was possibly due to N-mineralization and N uptake by crops. Yao et al. [38] also reported that available N in the fertilization treatment showed that a combination of organic fertilizer and mushroom residue could reduce the available N content in the soil in a short period of time. Under different returning concentrations, the available P content was higher than the CK treatment. The increase in available P in mushroom residue may be due to the high microbial activity caused by the addition of organic manure, which accelerated the phosphorus cycle [39].
Soil microorganisms are a sensitive and active part of soil properties. Dynamic changes in soil microorganisms can accurately reflect the changes in soil quality and play a dominant role in maintaining the stability of the ecosystem, soil nutrient decomposition and transformation process, and anti-interference [40,41,42]. Compared with other physical and chemical properties, soil microbial quantity and enzyme activity were more sensitive [43,44]. In this study, the changes in soil enzyme activity between different concentrations and soil layers after the residue was returned to the field were observed, indicating that the difference between different treatments was not significant at 20–30 cm; this may be because the nutrients required for microbial survival could not be provided due to the increase in soil depth. In our experiment, the number of soil microorganisms in the R11 treatment showed a downward trend because the R11 treatment provided more available soil nutrients, which may cause excess organic matter and make it difficult to achieve decomposition. Most reports indicated an increase in soil enzyme activity in organic crop treatments [45,46,47,48]. Many studies have shown that soil fertility levels are closely related to the type and activity of soil enzymes [49,50,51]. Deng Ouping [52] found that the in situ return of mushroom residue could significantly increase sucrase activity, and the activation of the enzymes and soil nutrients showed a good correlation. Hu et al. [22] showed that the sucrase and catalase activities were inhibited by the in situ return of mushroom residue. Phosphatase can participate in the decomposition of phosphorus. The results of Teng et al. [23] showed that applying Postreatus residue could increase soil catalase activity. The different results may have occurred because the soil enzyme activity is affected by various factors, such as other types of mushroom residue, soil types, planting systems, and climatic conditions. Our results also showed that soil microbial activity was significantly positively correlated with soil organic matter, available P, and K because the climatic conditions in the region made the above substances more convenient for microbial transformation and utilization.

5. Conclusions

These results indicated that the return of fungal affected soil aeration and permeability at different treatments. The water content can be increased by 26.26%. We found that the content of soil bulk density and soil water content in the same treatment were sensitized to porosity. The contents of soil available phosphorus, organic matter, and alkali-hydrolyzable nitrogen were higher under the condition of R11 (330 kg/40 m2). The addition of fungal residue to the field helped to improve soil parameters (SOM and AP), and this effect increased as the return concentration increased. Compared with CK, the number of bacteria, fungi, and actinomycetes increased by 1.94 times, 1.46 times, and 1.71 times, respectively. The trend of sucrase activity in the different soil layers was inconsistent. AK was strongly correlated with the other factors, and the microorganisms and enzyme activities were strongly associated (p < 0.01). The efficient use of fungal residue in the agro-pastoral ecotone of northern China is a sustainable and green biological measure. The conclusion provides a new method for the resource utilization of downstream wastes in the food industry. At the same time, as a pollution-free natural local good improver, it is very beneficial in terms of increasing the crop yield. Moreover, if this measure can be used in a large area of fragile land that is affected by desertification and salinization, the benefits of water storage and soil moisture conservation will be of great significance to the prevention and control of these issues.

Author Contributions

Writing—original draft F.Z.; investigation F.Z. and S.S.; methodology, F.Z.; formal analysis, R.M.; data curation, Z.M. (Ze Ma) and Z.M. (Zhongju Meng); writing—review and editing, Z.M. (Ze Ma) and Z.M. (Zhongju Meng). All authors have read and agreed to the published version of the manuscript.

Funding

This research was supported by Technical Challenge Overcoming Project of Inner Mongolia Autonomous Region [2021GG0073]; Desert Ecosystem Conservation and Restoration Innovation Team [BR22-13-03].

Data Availability Statement

The datasets generated during and/or analyzed during the current. study are available from the corresponding author on reasonable request.

Conflicts of Interest

The authors declare that they have no known competing financial interest or personal relationships that could have appeared to influence the work reported in this paper.

References

  1. Duan, Y.X.; Chun, L.L.; Xiao, S.; Hong, Y.R. The dynamics of desertification in the farming-pastoral region of North China over the past 10 years and their relationship to climate change and human activity. Catena 2014, 123, 11–22. [Google Scholar] [CrossRef]
  2. Kamel, M. Ecotone classification according to its origin. Pak. J. Biol. Sci. 2003, 6, 1553–1563. [Google Scholar] [CrossRef]
  3. Pfeiffer, L.; Lin, C.Y.C. Does efficient irrigation technology lead to reduced groundwater extraction? empirical evidence. J. Environ. Econ. Manag. 2014, 67, 189–208. [Google Scholar] [CrossRef]
  4. Wang, X.; Li, Y.; Chen, Y.; Lian, J.; Lu, Y.; Niu, Y.; Gong, X.; Yu, P. Temporal and spatial variation of extreme temperatures in an agro-pastoral ecotone of northern China from 1960 to 2016. Sci. Rep. 2018, 8, 8787. [Google Scholar] [CrossRef] [PubMed]
  5. Liu, J.H.; Gao, J.X.; Lv, S.H.; Han, Y.W.; Nie, Y.H. Shifting farming-pastoral ecotone in China under climate and land use changes. J. Arid Environ. 2011, 75, 298–308. [Google Scholar] [CrossRef]
  6. Qi, Y.B.; Chang, Q.R.; Jia, K.L.; Liu, M.Y.; Liu, J.; Chen, T. Temporal–spatial variability of desertification in an agro-pastoral transitional zone of northern Shaanxi Province, China. Catena 2012, 88, 37–45. [Google Scholar] [CrossRef]
  7. Wang, X.M.; Chen, H.F.; Hasi, E. Desertification in China: An assessment. Earth-Sci. Rev. 2008, 88, 188–206. [Google Scholar] [CrossRef]
  8. Qiu, J.Q.; Yu, D.Y. Spatial patterns and influence factors of ecosystem services in the Agro-pastoral ecotone of northern China: Taking the central and western regions of Inner Monglia as an example. Acta Ecol. Sin. 2023, 43, 1–12. [Google Scholar] [CrossRef]
  9. Zhang, F.S.; Wang, J.Q.; Zhang, W.F.; Cui, Z.L.; Ma, W.Q.; Chen, X.P.; Jiang, R.F. Nutrient use efficiencies of major cereal crops in China and measures for improvement. Acta Pedol. Sinia 2008, 45, 916–924. [Google Scholar] [CrossRef]
  10. Ju, X.T. The concept and meanings of nitrogen fertilizer availability ratio—Discussing misunderstanding of traditional nitrogen use efficiency. Acta Pedol. Sinia 2014, 51, 921–933. [Google Scholar] [CrossRef]
  11. Zeng, X.Y.; Ma, Y.T.; Ma, L.R. Utilization of straw in biomass energy in China. Renew. Sustain. Energy Rev. 2007, 11, 976–987. [Google Scholar] [CrossRef]
  12. Ma, C.Q.; Li, M.X. Effect of ratio and size added spent mushroom substrate on soil Properties and Growth of Fraxinus mandshurica Seedlings. J. Southwest For. Univ. 2022, 42, 80–87. [Google Scholar] [CrossRef]
  13. Hafifah, F.; Hanafi, M.; Rezania, S.; Mat, S.; Mohd, T.; Din, F. Environmentally sustainable applications of agro-based spent mushroom substrate (SMS): An overview. J. Mater. Cycles Waste Manag. 2018, 20, 1383–1396. [Google Scholar] [CrossRef]
  14. Liu, J.K.; Wu, S.Z.; Cheng, H.T.; Li, G.Y.; Li, Y.; Wang, J.C.; Li, Q.F. Advances in Utilization of Spent Mushroom Substrates Plant Growing Medium. Chin. J. Trop. Crops 2019, 41, 191–198. [Google Scholar] [CrossRef]
  15. Meng, X.; Liu, B.; Xi, C.; Luo, X.; Yuan, X.; Wang, X.; Zhu, W.; Wang, H.; Cui, Z. Effect of pig manure on the chemical composition and microbial diversity during co-composting with spent mushroom substrate and rice husks. Bioresour. Technol. 2018, 251, 22–30. [Google Scholar] [CrossRef] [PubMed]
  16. Li, Z.C. Fertilizer efficiency test of waste after mushroom cultivation. Edible Mushroom 1985, 42–45. [Google Scholar]
  17. He, R.F. Comprehensive utilization of edible fungi and biological resources. Amino Acids Biol. Resour. 1998, 20, 50–53. [Google Scholar]
  18. Shen, J.W.; Shen, A.Z.; Yu, T.; Huo, Y.F. Effects of different organic fertilizers on soil labile organic matter and enzyme activity. Plant Nutr. Fertil. Sci. 2007, 13, 631–636. [Google Scholar]
  19. Mannipieri, P.; Ascher, J.; Ceccherini, L.L.; Pietramellara, G.; Renella, G. Microbialdiversity and soil functions. Eur. J. Soil Sci. 2003, 54, 665–670. [Google Scholar] [CrossRef]
  20. Rajkumar, M.; Ae, N.; Prasad, M.N.V.; Freitas, H. Potential ofsiderophore-producing bacteria for improving heavy meta lphytoextraction. Trends Biotechnol. 2010, 28, 142–149. [Google Scholar] [CrossRef]
  21. Hong, Q.; Zhao, Y.; Chen, M.J.; Huang, J.C.; Feng, Z.Y.; Chen, H.; Zhang, J.J. Effects of in situ return of mushroom residue on soil organic matter, enzyme activities and bacterial diversity. J. Edible Fungi 2022, 29, 27–35. [Google Scholar] [CrossRef]
  22. Hu, L.J.; Li, Y.; Tian, S.B.; Wei, J.Y.; Liao, D.X.; Feng, M.Y.; Zhang, H.; Zou, M.; Hang, X.N. Effects of returning bacterial residue on physical and chemical properties, microbial and enzyme activities of vegetable soil. Chin. Agric. Sci. Bull. 2020, 36, 98–104. [Google Scholar]
  23. Teng, Q.; Zeng, M.F.; Lin, H.F.; Xie, Y.Q. Effects of returning bacterial residue on growth, soil nutrients and enzyme activities of lettuce. Chin. Agric. Sci. Bull. 2020, 36, 30–36. [Google Scholar]
  24. Li, X.J.; Hai, C.X.; Liu, G.T. Spring soil erodibility for different land use patterns in the north piedmont of the Yinshan Mountains. Arid Land Geogr. 2007, 30, 926–932. [Google Scholar] [CrossRef]
  25. Jia, Z.F.; Zhou, Q.P.; Lei, C.S.; Liu, W.H.; Liang, G.L.; Wei, X.X.; Liu, Y.; Ji, Y.J.; Liu, Y.C. Naked oats Qingyou No.3 variety standard. Chin. Qinghai J. Anim. Vet. Sci. 2014, 44, 59. [Google Scholar]
  26. Bao, S.D. Soil and Agricultural Chemistry Analysis; China Agriculture Press: Beijing, China, 2000. [Google Scholar]
  27. Lin, X.G. Principleand Methods of Soil Microbiology Research; Higher Education Press: Beijing, China, 2010. [Google Scholar]
  28. Li, Z.G.; Luo, Y.M.; Teng, Y. Soil and Environmental Microbial Research Method; Science Press: Beijing, China, 2008. [Google Scholar]
  29. Zhang, M.K.; Fang, L.P. Effect of tillage, fertilizer and green manure cropping on soil quality at an abandoned brick making site. Soil Till. Res. 2007, 93, 87–93. [Google Scholar] [CrossRef]
  30. Stewart, D.P.C.; Cameron, K.C.; Cornforth, I.S.; Sedcole, J.R. Effects of spent mushroom substrate on soil physical conditions and plant growth in an intensive horticultural system. Soil Res. 1998, 36, 899–912. [Google Scholar] [CrossRef]
  31. Gong, C.; Wang, X.D.; Ni, X.; Le, T.T.; Zeng, S.Y.; Ye, Z.Q. Effects of long-term application of edible fungus residue and chemical fertilizers on fractions of labile organic carbon and available nutrients in rice field soils. J. Zhejiang A F Univ. 2018, 35, 252–260. [Google Scholar] [CrossRef]
  32. Mu, P.; Zhang, E.H.; Wang, H.N.; Fang, Y.F. Effects of Continuous Returning Straw to Maize Tilth Soil on Chemical Character and Microbial Biomass. J. Soil Water Conserv. 2011, 25, 81–85. [Google Scholar]
  33. Gregorich, E.G.; Janzen, H.; Ellert, B.H.; Helgason, B.L.; Qian, B.; Zebarth, B.J.; Angers, D.A.; Beyaert, R.P.; Drury, C.F.; Duguid, S.D.; et al. Litter decay controlled by temperature, not soil properties, affecting future soil carbon. Glob. Chang. Biol. 2017, 23, 1725–1734. [Google Scholar] [CrossRef]
  34. Medina, E.; Paredes, C.; Bustamante, M.A.; Moral, R.; Moreno-Caselles, J. Relationships between soil physico-chemical, chemical and biological properties in a soil amended with spent mushroom substrate. Geoderma 2012, 173, 152–161. [Google Scholar] [CrossRef]
  35. Chun, J.H.; Kim, S.; Arasu, M.V.; Al-Dhabi, N.A.; Chung, D.Y.; Kim, S.J. Combined effect of Nitrogen, Phosphorus and Potassium fertilizers on the contents of glucosinolates in rocket salad (Eruca sativa Mill.). Saudi J. Biol. Sci. 2017, 24, 436–443. [Google Scholar] [CrossRef] [PubMed]
  36. Wang, S.J.; Han, X.Z.; Hou, X.Y. Impact of Long-Term Fertilization on Nitrogen Mineralization and Nitrificati on in Black Soil. J. Soil Water Conserv. 2008, 22, 170–173. [Google Scholar]
  37. Meng, X.; Liu, B.; Zhang, H.; Wu, J.; Yuan, X.; Cui, Z. Co-composting of the biogas residues and spent mushroom substrate: Physicochemical properties and maturity assessment. Bioresour. Technol. 2019, 276, 281–287. [Google Scholar] [CrossRef]
  38. Yao, J.W.; Ai, S.Y.; Wang, Y.H.; Li, M.J.; Tang, M.D.; Zen, Z.B. Effect of urea, ammonium bicarbonate and their combined application with organic fertilizer on successive plantation of leafy vegetables. Chin. Agric. Sci. Bull. 2009, 25, 241–244. (In Chinese) [Google Scholar]
  39. Parham, J.A.; Deng, S.P.; Raun, W.R.; Johnson, G.V. Long-term cattle manure application in soil, I. Effect on soil phosphorus levels, microbial biomass C, and deshydrogenase and phosphatase activities. Biol. Fertil. Soil 2002, 35, 328–337. [Google Scholar]
  40. Lin, X.G.; Hu, J.L. The scientific connotation of soil microbial diversity and its ecological service function. Acta Pedol. Since 2008, 45, 892–900. [Google Scholar]
  41. Wu, J.F.; Lin, X.G. The role of soil microorganisms in promoting plant growth. Soil 2003, 1, 18–21. [Google Scholar]
  42. Cheng, M.; Xie, W.Y.; Yang, Z.X.; Zhou, H.P. Effects of long-term straw return on corn yield, soil nutrient contents and enzyme activities in dryland of the Loess Plateau, China. Chin. J. Eco-Agric. 2019, 27, 1528–1536. [Google Scholar] [CrossRef]
  43. Doran, J.W.; Sarrantonin, M.; Liebig, M.A. Soil health and sustainability. Adv. Agron. 1996, 56, 1–54. [Google Scholar] [CrossRef]
  44. Shi, S.B.; Wang, X.D.; Ye, Z.Q.; Chen, W.B.; Li, T.; Chen, J.H.; Li, J.W. Effect of the combined application of fungal residue and chemical fertilizers on the mineralization of soil organic carbon in paddy fields. Environ. Sci. Pollut. Res. 2019, 26, 1–13. [Google Scholar] [CrossRef]
  45. Dick, R.P.; Rasmussen, P.E.; Kerle, E.A. Influence of long-term residue management on soil enzyme activity in relation to soil chemical properties of a wheat–fallow system. Soil Biol. Biochem. 1988, 6, l59–l64. [Google Scholar] [CrossRef]
  46. Martens, D.A.; Johanson, J.B.; Frankeberger, W.T., Jr. Production and persistence of soil enzymes with repeated additions of organic residues. Soil Sci. 1992, 153, 53–61. [Google Scholar] [CrossRef]
  47. Yang, L.J.; Li, T.L.; Li, F.S.; Lemcoff, J.H.; Cohen, S. Fertilization regulates soil enzymatic activity and fertility dynamics in a cucumber field. Sci. Hortic. 2008, 116, 21–26. [Google Scholar] [CrossRef]
  48. Zhao, Y.C.; Wang, P.; Li, J.L.; Chen, Y.R.; Ying, X.Z.; Liu, S.Y. The effects of two organic manures on soil properties and crop yields on a temperate calcareous soil under a wheat–maize cropping system. Eur. J. Agron. 2009, 31, 36–42. [Google Scholar] [CrossRef]
  49. Liu, J.X. Correlative research on the activity of enzyme and soil nutrient in the different types of farmland. Chin. J. Soil Sci. 2004, 35, 20–23. (In Chinese) [Google Scholar]
  50. Liu, E.K.; Zhao, B.Q.; Li, X.Y.; Jiang, R.B.; Li, Y.T.; Hwat, B.S. Biological properties and enzymatic activity of arable soils affected by long-term different fertilization systems. J. Plant Ecol. 2008, 32, 176–182. (In Chinese) [Google Scholar]
  51. Fan, J.; Hao, M.D. Study on long-term orientation of dryland rotation and fertilization in the loess plateauⅡ. Soil enzyme activity and soil fertility. Plant Nutr. Fertil. Sci. 2003, 9, 146–150. (In Chinese) [Google Scholar]
  52. Deng, O.P.; Xie, T.; Li, Y.; Deng, L.J. Effect of Different Residue Covering Mode on Soil Enzyme Activity Under Rice-wheat Rotation. J. Agro-Environ. Sci. 2013, 2, 2027–2034. [Google Scholar]
Agronomy 13 02432 g001
Figure 1. Experimental schematic diagram.
Figure 1. Experimental schematic diagram.
Agronomy 13 02432 g001
Agronomy 13 02432 g002
Figure 2. Effects of returning fungal residue return on soil chemical properties. Note: Different letters indicate significant differences (p < 0.05) among different treatments. (a): Alkaline hydrolysis nitrogen (AN); (b): Alkaline pootassium (AK); (c): Alkaline phosphorus (AP); (d): Soil organic matter (SOM).
Figure 2. Effects of returning fungal residue return on soil chemical properties. Note: Different letters indicate significant differences (p < 0.05) among different treatments. (a): Alkaline hydrolysis nitrogen (AN); (b): Alkaline pootassium (AK); (c): Alkaline phosphorus (AP); (d): Soil organic matter (SOM).
Agronomy 13 02432 g002
Agronomy 13 02432 g003
Figure 3. Effects of return fungal residue on microbial quantity. Note: The significance levels are * p < 0.05; ** p < 0.01. (a): Number of bacteria; (b): Number of actinomycetes; (c): Number of fungi.
Figure 3. Effects of return fungal residue on microbial quantity. Note: The significance levels are * p < 0.05; ** p < 0.01. (a): Number of bacteria; (b): Number of actinomycetes; (c): Number of fungi.
Agronomy 13 02432 g003
Agronomy 13 02432 g004
Figure 4. Effects of fungal residue return on enzyme activity. (a): Soil acid phosphatase (SAP); (b): Soil sucrase (SS); (c): Soil urease (SU).
Figure 4. Effects of fungal residue return on enzyme activity. (a): Soil acid phosphatase (SAP); (b): Soil sucrase (SS); (c): Soil urease (SU).
Agronomy 13 02432 g004
Agronomy 13 02432 g005
Figure 5. Relationship between soil factors. Red indicates positive correlations between parameters, and blue indicates negative correlations between parameters. The significance levels are * p < 0.05; ** p < 0.01.
Figure 5. Relationship between soil factors. Red indicates positive correlations between parameters, and blue indicates negative correlations between parameters. The significance levels are * p < 0.05; ** p < 0.01.
Agronomy 13 02432 g005
Table 1. Baseline soil values of experimental plot.
Table 1. Baseline soil values of experimental plot.
Soil Depth
(cm)		SOM
(g/kg)		AN
(mg/g)		AP
(mg/g)		AK
(mg/g)		TN
(g/kg)		TP
(g/Kg)		TK
(g/Kg)
0–1014.9858.124.51110.130.890.4236.77
10–2014.7256.033.6296.250.910.2637.83
20–3014.9148.172.7396.450.760.3430.66
Note: SOM: soil organic matter; AN: soil alkali-hydrolyzable nitrogen; AP: soil available phosphorus; AK: soil available potassium; TN: soil total nitrogen; TP: soil total phosphorus; TK: total potassium in soil.
Table 2. Return amounts for different treatments.
Table 2. Return amounts for different treatments.
TreatmentValue (kg/40 m2)
CK0
R390
R5150
R7210
R9270
R11330
Table 3. The effects of different treatments on soil physical properties.
Table 3. The effects of different treatments on soil physical properties.
Treatment Soil Bulk Density (g/cm3)Soil Porosity (%)Soil Water Content (%)
0–10 (cm)10–20 (cm)20–30 (cm)0–10 (cm)10–20 (cm)20–30 (cm)0–10 (cm)10–20 (cm)20–30 (cm)
CK1.51 ± 0.02 a1.58 ± 0.06 a1.59 ± 0.03 a41.13 ± 1.30 a40.21 ± 1.38 a39.60 ± 0.90 a2.97 ± 0.06 a3.08 ± 0.06 a3.23 ± 0.04 a
R31.50 ± 0.02 a1.52 ± 0.04 a1.58 ± 0.04 a41.53 ± 0.80 a41.27 ± 0.61 a39.50 ± 0.89 a3.01 ± 0.02 a3.15 ± 0.08 a3.27 ± 0.02 a
R51.47 ± 0.05 a1.47 ± 0.03 b1.52 ± 0.05 a41.67 ± 0.90 a41.36 ± 0.60 a39.73 ± 1.06 a3.18 ± 0.01 b3.28 ± 0.03 b3.28 ± 0.02 a
R71.35 ± 0.11 b1.48 ± 0.03 b1.50 ± 0.02 b42.37 ± 0.88 a41.97 ± 0.87 a40.17 ± 1.44 a3.35 ± 0.04 b3.52 ± 0.03 b3.24 ± 0.11 a
R91.23 ± 0.04 b1.46 ± 0.01 b1.46 ± 0.06 b43.63 ± 1.17 b42.63 ± 1.07 b41.60 ± 0.90 a3.45 ± 0.04 b3.74 ± 0.10 b3.22 ± 0.07 a
R111.12 ± 0.05 b1.45 ± 0.03 b1.42 ± 0.03 b45.67 ± 1.50 b43.29 ± 1.50 b44.40 ± 1.97 b3.75 ± 0.05 b3.81 ± 0.06 b3.24 ± 0.03 a
Note: Different letters indicate significant differences (p < 0.05) among different treatments.
Table 4. Number of soil microorganisms in 0–30 layers.
Table 4. Number of soil microorganisms in 0–30 layers.
TreatmentNumber of Bacteria
(×105 cfu/g)		Proportion
(%)		Number of Fungi
(×103 cfu/g)		Proportion
(%)		Number of Actinomycetes
(×105 cfu/g)		Proportion
(%)		Total Microorganisms
(×105 cfu/g)
CK6458.13%1101.00%4540.87%110.10
R36858.55%1140.98%4740.47%116.14
R59559.26%1310.82%6439.92%160.31
R711159.53%1450.78%7439.69%186.45
R912661.00%1550.75%7938.25%206.55
R1112561.39%1600.79%7737.82%203.60
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

Zhao, F.; Shi, S.; Meng, R.; Ma, Z.; Meng, Z. Soil Habitats Are Affected by Fungal Waste Recycling on Farmland in Agro-Pastoral Ecotone in Northern China. Agronomy 2023, 13, 2432. https://doi.org/10.3390/agronomy13092432

AMA Style

Zhao F, Shi S, Meng R, Ma Z, Meng Z. Soil Habitats Are Affected by Fungal Waste Recycling on Farmland in Agro-Pastoral Ecotone in Northern China. Agronomy. 2023; 13(9):2432. https://doi.org/10.3390/agronomy13092432

Chicago/Turabian Style

Zhao, Feiyan, Shiling Shi, Ruibing Meng, Ze Ma, and Zhongju Meng. 2023. "Soil Habitats Are Affected by Fungal Waste Recycling on Farmland in Agro-Pastoral Ecotone in Northern China" Agronomy 13, no. 9: 2432. https://doi.org/10.3390/agronomy13092432

APA Style

Zhao, F., Shi, S., Meng, R., Ma, Z., & Meng, Z. (2023). Soil Habitats Are Affected by Fungal Waste Recycling on Farmland in Agro-Pastoral Ecotone in Northern China. Agronomy, 13(9), 2432. https://doi.org/10.3390/agronomy13092432

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