Review of the Relationship between Soil Health, Climate Change Mitigation, and Crop Production When Soils Are Enhanced with Organic Sources of Nutrients

Abstract

When soils are not properly maintained, the agriculture sector contributes significantly to global warming by raising greenhouse gases like CO₂ and N₂O. This review describes the relationship between organic fertilizers in improving soil health, crop production and mitigating climate change. Organic fertilizers are produced by the quick artificial decomposition from biological wastes. The synergy of using both poultry manure and nitrogen has proven to enhance the production of crops. The utilization of 4 t t ha⁻¹ of poultry manure resulted in the most significant development and production of maize. Likewise, utilization of bio-slurry in both liquid and composted forms, either alone at a rate of 20 t ha⁻¹ or in combination with the complete dose of chemical fertilizer at a rate of 10 t ha⁻¹, results in varying increases in crop yield of maize, soybean, wheat, sunflower, cotton, ground nut, cabbage, and potato compared to the control group. By utilizing organic sources of nutrients, the emissions of N₂O can be diminished through the enhancement of nitrogen utilization effectiveness. Organic source of nutrients possesses numerous characteristics that not only enhance crop yield but also serve as options for safeguarding the environment by enhancing soil organic carbon and reducing N₂O emission.

1. Introduction

By 2050, the world populace is assessed to be 9.2 billion. Horticulture may be essential for feasible advancement, destitution decrease, and nourishment security in developing countries. During this period, they have to increment rural generation by 70% to meet the expanded request for food [1]. The food supply in sub-Saharan Africa faces difficulties as the human population grows and the opportunities to expand arable land are limited. There is a constant decrease in soil fertility, which results in declining yields. The cultivation of essential crops such as rice and wheat is anticipated to be detrimentally affected by climate change, projected to affect a minimum of 22% of these areas by the year 2050 [2] and Exacerbate the phenomenon of worldwide climate change. The escalation in the amount of greenhouse gases (GHGs), primarily carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂O), in the atmosphere, is the leading cause of global warming. The majority of developing nations rely on the agricultural industry as their main source of economic stability [3]. Among the challenges hampering agricultural productivity in sub-Saharan Africa, the inadequacy of soil nutrients and ineffective land management techniques have been recognized as major obstacles [4].

The agricultural sector accounts for a substantial portion of greenhouse gas emissions, particularly from livestock through processes such as intestinal fermentation and the management of manure, as well as from agricultural soils due to the application of excessive nitrogen fertilizers and the decomposition of organic matter. Roughly 14% of the total worldwide emissions of greenhouse gases can be attributed to agriculture [5]. The solution to the impacts of climate change is partially found within the problem itself. With proper management of cultivated soil and implementation of efficient policies, significant amounts of carbon can be absorbed from the atmosphere and stored in the soil, which would subsequently lead to a decrease in CH₄ and CO₂ emissions [6]. Prolonged utilization of mineral fertilizers deteriorates the chemical, physical, and biological properties of soil along with its overall health [7]. The usage of organic fertilizers as a source of nutrients is gaining popularity due to the escalating costs and detrimental impacts of chemical fertilizers [7, 8]. The inadequate utilization of organic fertilizers by rural Ethiopian farmers is negatively affecting crop production in the area and the general food safety situation.

One solution suggested for the soil fertility crisis in sub-Saharan Africa is the use of organic resources, considered the most practical choice [9]. Several types of organic resources can be utilized, namely farm manure (FYM), poultry litter (PL), poultry manure (PM), as well as manure and vermicompost [9] and by up to 50% [10]. For example, organic materials such as FYM are traditionally used by rice farmers [8]. FYM provides essential nutrients, including N, P, K, Ca, Mg, and S, that are crucial for the growth of plants. It also contains micronutrients such as Fe, Mn, Cu, and Zn. Therefore, it serves as a combination of nourishment for plants [11]. It improves soil’s physical, chemical, and biological properties [5]. The structure can be improved by employing organic FYM on soil, leading to better growth conditions for roots [12]. Farmyard manure enhances the ability of the soil to retain water [13]. The utilization of organic fertilizers to enhance soil texture and nutrient transfer and sustain soil well-being has generated curiosity regarding organic cultivation [5]. Chicken manure is the primary organic fertilizer of substantial importance due to its high levels of essential nutrients like nitrogen, phosphorus, and potassium. According to [14], the utilization of chicken manure led to a rise in exchangeable soil cations and nitrogen levels, elevating it from 0.09 to 0.14%. The excrement produced by chickens on farms, commonly known as chicken manure, undergoes a gradual process of decomposition and displays a considerably elevated level of phosphorus in comparison to other organic materials used for nutritional purposes. It comprises approximately 3.03% nitrogen, 2.63% phosphorus, and 1.4% potash [15].

Having a comprehensive knowledge of the impact of carbon, nitrogen, and essential soil characteristics on soil gas emissions is crucial in order to minimize the long-lasting negative consequences that may arise even after discontinuation of the use of fertilizers and composts. This is an important step toward mitigating the residual effects. This paper aims to determine how organic fertilizers can enhance soil productivity, secure food supply, and safeguard the environment against climate change. The primary aim of the review is to examine the role of organic fertilizers in enhancing the yield of crops. Examine the significance of using organic fertilizers in relation to enhancing soil fertility, promoting crop yields, mitigating climate change, and analyzing their effects on ensuring sustainable agricultural practices.

2. Concepts of organic fertilizers

Organic fertilizers refer to naturally occurring substances that possess a well-defined chemical composition and offer plant nutrients in a readily available form, thereby possessing a high analytical worth [16]. Organic fertilizers comprise fertilizers obtained from animal waste, human waste, or plant material (such as vegetables), organic matter such as compost and manure. The use of organic fertilizers involves using raw materials derived from nature, typically referring to our biodegradable apparel. Normally, compost is created through the process of breaking down materials that can be naturally broken down. These waste materials encompass paper, foliage, peels from fruits, uneaten food items, and also fruit juices. The incorporation of organic fertilizers is a beneficial supplement to enhance the quality of the soil. This facilitates the soil to attain an optimum condition for cultivation.

2.1 Organic fertilizer on crop production and soil nutrients

According to [17] the report, the most successful results in terms of grain yield and test weight were obtained through the utilization of 10 tons per hectare of PM, paired with 125 kilograms per hectare of nitrogen in the form of urea. The utilization of various levels of N, PM, and their combination did not significantly impact the concentrations of P and K in both the plant stover and grain. According to research, the utilization of poultry manure resulted in a significant enhancement of crop growth and maize yield by up to 40%. The implementation of four tons of PM per hectare led to the most substantial development and productivity of maize [18]. Indeed [19] reported the utilization of organic fertilizers may result in a substantial productivity boost of 15.2% for kiwifruit, as opposed to using mineral fertilizers. The nutrient levels in kiwifruits may be increased by using organic fertilizers. The outcomes indicated that organic fertilizers that have abundant quantities of diminutive organic matter could be more effective in stimulating crop yield.

The active small molecular organic matter in the produced organic fertilizer led to more noticeable effects compared to the conventional organic fertilizer derived from fermented pig manure. One reason for the ease of mineralization and subsequent release of mineral nutrients into the soil is the smaller size of organic molecules. Low molecular weight organic acids, which belong to the group of small organic molecules, have been extensively demonstrated to aid in the mobilization of soil P by means of dissolution and complex formation [19, 20]. The increased accessibility of metallic elements can be achieved through the creation of organic-metal complexes using low molecular weight organic acids [21]. Additionally, the employment of the AF application resulted in improved fruit characteristics such as increased firmness and higher levels of soluble solid, soluble sugar, titratable acid, and vitamin C. Other investigations had reported comparable findings. Ma et al. [19] it has been discovered that the organic matter present in soil had a direct association with the weight per fruit, levels of soluble solids, soluble sugar, and vermicompost (VC) content in jujuba fruits. Hence, organic fertilizer appears to be a valuable and environmentally friendly way to improve the mineral availability in the soil and improve fruit quality of tomato [22]. Despite the utilization of fermented pig manure containing equal levels of organic matter, the utilization of mineral fertilizer with OF (organic fertilizer) intervention did not lead to any enhancement in the yield or caliber of kiwifruits. According to Fallahi and Seyedbagheri [23] suggestion that humic substances do not have an impact on the quality of apples implies that organic matters with high molecular weights that are resistant to degradation are not significantly conducive to the growth of crops.

2.1.1 Roles of small molecular organic matters for crops

The introduction of the mineral plant nutrition theory has substantially ensured our food security since its inception [24]. It must be acknowledged that the accumulation of organic matter is an integral part of the growth of crops. Carbon is, without a doubt, the crucial factor determining the growth of crops. The crops are experiencing a lack of carbon absorption to a certain extent. As an illustration, augmenting the CO₂ levels within the greenhouse has the potential to boost crop yield by providing an ample amount of CO₂ for the process of photosynthesis [25, 26]. Moreover, plants have the ability to absorb nutrients from both their roots and leaves, including minute organic substances, in order to foster their development. Sulmon et al. [27] reported that, the utilization of external carbohydrates was employed to enhance the process of phytoremediation, given that the plants were capable of incorporating the exogenous carbohydrates.

Apart from carbon, it is possible for plants to inherently obtain nitrogen directly from organic sources without the need for microbial mineralization [28]. Hirner et al. [29] discovered a transporter in the root epidermis with a strong affinity for taking in amino acids at the cellular level. Ge et al. [30] also noted that glycine N uptake accounted for 21% of nitrogen uptake in tomatoes, following that of KNO₃-N and NH₄Cl-N. Crops can directly absorb other types of small N-molecules like urea, polyamines, and polypeptides resulting from enzymatic cleavage [29].

Utilizing small organic molecules such as amino acids, peptides, and carbohydrates directly provides a more effective means of enhancing crop growth without the need for numerous assimilation processes compared to the absorption of CO₂. Furthermore, vegetation would redistribute their natural substances in order to combat environmental stress [30, 31]. Adding live natural substances to the soil could help protect crops and safeguard their investment of carbon against environmental challenges. Utilizing organic fertilizers that contain high levels of active small molecular organic agents can enhance both the yield and quality of crops, as compared to traditional organic fertilizers.

2.1.2 Effect of compost on yield of cereals

The study conducted adaa district Eastern Shewa Oromia region by Bhattacharyya et al. [32] indicated that the combination of dry matter compost and inorganic fertilizers resulted in a grain yield value of 0.67 t ha⁻¹ for bread wheat. The untreated region or area had the lowest crop output, quantified at 260 grams per square meter or 2.6 t ha⁻¹ . Previous studies conducted have confirmed similar results. On the other hand, a study conducted by [33] in the Tigray area, it has been observed that the cultivation of teff and barley in plots treated with mineral fertilizer and 6.4 t ha⁻¹ yr⁻¹compost results in a substantial increase in grain yield compared to plots treated with 3.2 t ha⁻¹ yr⁻¹ compost and control plots. The plots treated with 6.4 t ha⁻¹ compost and mineral fertilizer displayed no noticeable disparity.

2.1.3 Effects of crop residue

The utilization of crop residues as a soil enhancer is frequently restricted because it poses difficulties for both mechanical and manual cultivation, as well as causing harmful impacts on crop output due to the presence and continuation of pests and diseases [34] allelopathy and short-term nutrient deficiency [35].

A large proportion of crop residues are either utilized as cattle feed or incinerated due to these factors. Ocio et al. [36] evaluated that edit residue contain on normal 40, 10, and 80% of the N, P, and K right now connected as fertilizer. A ton of maize buildup contains 4–8 kg N, 1.5–1.8 kg P, 13–16 kg K, 3.8–6.6 kg Ca, and 1.5–3.4 kg Mg. Buildups of cereal crops include 60 to 75% of the whole biomass generation and have lower supplement concentrations than the grain [37]. In this manner, returning them to the soil frameworks especially, where no or moo inputs are utilized, is fundamental in abating supplement misfortunes. Be that as it may, edit buildups by themselves are not sufficient to balanced supplement mining in sub-Saharan Africa. Edit buildup administration impacts the accessibility of supplements, particularly N. Agreeing with the consideration conducted by Dejene [37] in Gozamen Woreda Eastern Gojam Amhara Local, crop residue is commonly utilized for keeping up soil richness and crop production in two ways.

2.1.4 Effects of farm yard manure on soil fertility and yield

As Tolessa and Friesen [38] detailed natural fertilizers, particularly FYM, have a noteworthy part in keeping up and moving forward the chemical, physical, and organic properties of soils and in supporting maize abdicate in the western portion of Ethiopia. They moreover detailed that 10 t ha⁻¹ of FYM are measurably at proportionality with the current agronomic suggestion of inorganic fertilizers N and P for maize. Another study by Zelalem [39, 40] at Haraghe Zone Oromia Locale Eastern Ethiopia showed that 10 t ha⁻¹ of FYM and 100 kg ha⁻¹ N + 100 kg ha⁻¹ P appeared no noteworthy distinction on maize grain abdicate but altogether vary from the control treatment. Moreover, Negassa, et al. [40] demonstrated that the direness of utilizing natural excrement has been picking up ground within the wake of expanding, taken a toll on fertilizer with each passing year, and certain other characteristic impediments with the utilization of chemical fertilizers.

2.1.5 Effects of green manure on soil fertility

The study conducted by Getu and Teshager [41] on the impact of green excrement plants on sorghum surrender and soil ripeness in eastern Amhara of Ethiopia uncovered that there was factually noteworthy (P < 0.05) distinction within the grain surrender of sorghum due to the impact of intercropping with the green fertilizers.

2.1.6 Effects of biogas slurry on yield

Using bio-slurry as a liquid or composted application, either on its own at 20 t ha⁻¹ or combined with a full dose of chemical fertilizer at 10 t ha⁻¹, resulted in improved percentages of yield for a variety of crops (maize, soybean, wheat, sunflower, cotton, groundnut, cabbage, and potato) when compared to controls [42]. According to Krishna [43] by utilizing bio-slurry, the crop production of rice and maize observed a rise of 34 percent while wheat saw an increase of 25 percent. The application of bio-slurry in various forms elevated both the amount and caliber of the harvest, including crops, vegetables, and fruits, in addition to enhancing the plants’ resistance to diseases [42]. Indeed [44], a study was conducted that compared the impact of biogas slurry and inorganic fertilizer on soil characteristics, as well as the growth and yield of white cabbage (Brassica oleracea var. capitata f. alba). At Sebeta Hawas Woreda, South West Shewa zone Oromia Region, it was found that using a combination of slurry compost and a complete dose of fertilizer resulted in a 38.4% increase in crop yield compared to using a full dose of inorganic fertilizer alone. Five tons of slurry compost when it came to crop yield. Slurry compost quantity of 8 tons per hectare.

2.1.7 Effects of poultry manure on soil fertility and yield and yield-related parameters

An exceptional natural fertilizer, poultry manure is rich in essential nutrients like nitrogen, phosphorus, potassium, and others. Unlike chemical fertilizer, it contributes organic matter to the soil that enhances soil quality, increases nutrient retention, promotes aeration, boosts soil moisture retention, and improves water infiltration [45]. According to the findings, poultry waste offers a more easily accessible source of phosphorus for plants compared to other forms of organic manure [46]. Poultry waste proves to be a useful fertilizer and can potentially replace the use of synthetic fertilizers.

The utilization of poultry manure resulted in a significant rise of 53% in soil nitrogen levels, increasing from 0.09 to 0.14%. In addition, the application of manure enhanced the presence of exchangeable cations in the soil [47]. The primary motives for utilizing PM in agriculture are to improve soil quality through organic amendment and to supply crops with essential nutrients [48]. Likewise, [49] reported that the use of PM significantly impacted various aspects of maize growth and yield, including plant height, row count per cob, number of grains per row, the weight of 1000 grains, grain yield, biological yield, and harvest index. The highest possible values for each parameter were observed when 12 tonnes per hectare of PM were utilized. The author previously stated that the composition of PM includes approximately 2.04% nitrogen, 2.06% phosphorus, and 1.86% potassium). Indeed [48], according to the data, PM comprises approximately 3.03% nitrogen, 2.63% phosphorus, and 1.4% potash. The data presented indicates that the plot where 12 t ha⁻¹ of poultry manure was utilized had the highest grain yield with a significant value of 5.11 t ha⁻¹. The next highest yield was recorded from the plot using 10 t ha⁻¹ PM, which was statistically equivalent to the setup that used 8 t ha⁻¹ PM, and produced grain yields of 4.16 and 3.60 t ha⁻¹, respectively. The plots treated with 6 t ha⁻¹ poultry manure had a statistically identical grain yield to that of the control treatment. According to [47] reported that poultry manure significantly increased grain yield.

According to findings [50], it is suggested that utilizing poultry manure to replace 50% of inorganic fertilizer can effectively minimize the need for chemical fertilizers while maintaining crop productivity. The utilization of fertilizers containing 50% NPK and 100% PM and fertilizers containing pure 100% NPK resulted in the most bountiful pod and seed yields per plant. The control and 100% PM treatments exhibited the minimum amount of pods per plant and seed yield per plant. The finest origin of crop nutrients is poultry waste (Table 1).

Nutrient element	Values (%)
N	4.50
P2O5	2.50
K2O5	2.00
CaO	2.00
MgO	1.00
S	0.50
Fe	0.04
Mn	0.09
Zn	0.09
Other characteristics	0.50

Table 1.

Chemical composition of poultry manure [50].

2.2 Organic fertilizer on quality improvement

The primary physical reason for the decrease in food production per person in Ethiopia is acknowledged as the result of land deterioration and the resulting reduction in soil productivity [15]. The depletion of land’s ability to support crops and livestock caused by the use of man-made chemicals has a direct negative impact on the production of food and animal feed. The use of chemical substances leads to a decrease in land productivity, which is worsened by inadequate land administration [51]. Nevertheless, it is possible to reduce it by utilizing organic fertilizers that are derived from excrement and urine [52].

The fertility of soil can be enhanced through the use of organic fertilizers that have an impact on its physical, chemical, and biological qualities. It enhances the movement of water and air through the soil, thereby boosting its capacity to retain moisture [53]. According to [54] According to the report, the usage of organic fertilizers also has a positive impact on the soil as it generates clay humic complexes that boost the soil’s ability to adsorb vital nutrients like calcium, magnesium, and potassium. Furthermore, it enhances the activity of microorganisms that participate in the mineralization process. A study conducted by [55] stated that the soil pH incorporating organic matter into the soil could substantially elevate the pH level, as well. The elevated presence of fundamental nutrients in organic supplements and the reduction of hydrous oxides in soil with the aid of poultry manure are the reasons assigned for this outcome [56].

According to [57] findings, animal manure is the prime source of soil fertility management to improve the way for many farmers in Ethiopia. It is used as fertilizer to ameliorate soil fertility depletion in many parts of Ethiopia. Indeed [58], according to findings, approximately 87% of farmers in Kindo Koisha, a region in Southern Ethiopia, use animal manure. The reason for this is that the utilization of animal excrement leaves a lasting impact on the land [59]. The impact may differ depending on the quantities administered. The feasibility of this is reliant on the presence of domestic animals and the assistance of family workers for transportation to their farming lands [60]. Currently, biomass is widely utilized as a primary source of energy in households [51]. The utilization of PM significantly raised the levels of exchangeable cations and soil nitrogen content, elevating them from 0.09 to 0.14% [47]. The physical and chemical condition, specifically nitrogen content, of the soil was enhanced by the utilization of 10 tons per hectare of PM in conjunction with 125 kg of N [16].

2.3 Organic fertilizer on climate change mitigation

Soil microbes and the atmosphere benefit from the ecosystemic role of soils. If appropriately managed, soil can function as a significant tool for reducing the impact of climate change by sequestering carbon and reducing the discharge of greenhouse gases into the atmosphere. On the contrary, soil carbon can emanate in the form of carbon dioxide (CO₂) and add to climate change if the soil is not managed effectively or farmed using unsustainable agricultural methods. The gradual transformation of grassy and wooded areas into cultivation and pasturage lands throughout many centuries has caused extensive depletion of soil carbon on a global scale. Revitalizing depleted soil and embracing methods to conserve soil can significantly reduce greenhouse gas emissions from farming, promote carbon storage, and reinforce the ability to cope with climate change [57].

The earth’s soil contains the most significant carbon reservoir on land, and the biogeochemical reactions happening in the soil regulate the release and absorption of greenhouse gases into the atmosphere [58]. When implementing sustainable methods to improve soil organic matter, it is important to also address the causes of soil deterioration and protect the current levels of soil carbon, especially in soils that have a high amount of organic carbon [61].

Soil-based carbon sequestration will aid in both adapting to and mitigating the effects of climate change. This will enhance the sustainability of agricultural production systems, improve the resilience of agricultural ecosystems as a whole, and uphold the ecosystem services that rely on soils [62].

The world’s agricultural soils span across approximately 1.5 billion hectares and possess a significant ability to sequester carbon [63]. Efficiently controlling the pool of organic carbon within the soil is a crucial objective toward attaining both adaptation and mitigation of the worldwide environmental impact [64], while advancing global food security [65]. Cropland soils are significant carbon sinks that can be utilized to alleviate and adjust to worldwide climate change. The amount and speed at which soil organic carbon is stored (typically approximately 0.55 × 10⁻⁹ Pg C ha⁻¹ y⁻¹) depend on factors such as how residues are managed, and organic material is recycled, the climate, nitrogen application, and properties of the soil [64]. Like cropland soil, forest and grassland soil also have the potential to play a vital role in carbon sequestration. Soil enriched with organic fertilizer can enhance its capacity to absorb carbon, boosting soil fertility management. Effective nutrient management plays a crucial role in the sequestration of soil organic carbon (SOC), which in turn emphasizes the significance of enhancing soil fertility [66]; the levels of organic carbon and nitrogen in soil are crucial factors that determine soil productivity and quality by enhancing physical, chemical, and biological processes such as nutrient cycling, water preservation, growth of root and shoot, and upkeep of ecological health [67].

2.4 Organic fertilization for sustainable agriculture

The incorporation of organic substances into the soil can enhance soil characteristics and maintain an enduring agricultural output. Furthermore, organic substances that are of low molecular weight have the potential to participate in the regulation of both soil nutrient dynamics and agricultural productivity. According to [66] study in Nigeria reported, when 10 metric tons per hectare of PM along with urea and muriate of potash fertilizer were utilized, a sustainability index (SI) of 72.5% was observed. According to the study, using 10 tons of PM alongside NK that has a 72.5% SI is a more efficient and ecologically sound approach than utilizing NK, with the highest agronomic efficiency and partial factor productivity. Using a combination of synthetic and poultry manure as a source of P can result in higher profitability and sustainability in the long run [68]. Similarly to Sainju & Good (1993), the utilization of P60SSP + 60 PM enables the easy accessibility of phosphorus nutrients present in fertilizers and manure, thereby enhancing the quality of soil constituents. As a result, it can be inferred that farmers residing in semi-moist regions ought to utilize a combined approach of adding P into the soil, with an equal division of 60 kg ha⁻¹ from both single super phosphate (SSP) and poultry manure. This will not only enhance the applied fertilizer phosphorus uptake efficiency (AFPU), fertilizer phosphorus use efficiency (FPUE), and phosphorus index ratio (PIR), but also generate greater and consistent wheat yields. Furthermore, by adopting this method, there will be reduced dependence on chemical fertilizers, which in turn will lower the potential dangers connected to continuous and excessive use of synthetic fertilizers on the soil and atmosphere.

2.5 Determinant factors for organic fertilizers

According to [69], several factors significantly influenced the adoption of organic fertilizers in Ethiopia, including the age and marital status of the household head, educational level, labor availability, farming experience, farm, and livestock size, access to information and extension services, labor costs, household income, soil fertility, and distance between the farm and home.

3. Conclusions

Based on an analysis of various literary sources, it has been determined that the following points are evident. Based on the review, one can infer or deduce.

• The usage of organic fertilizer enhances the production of a variety of agricultural crops.

• Because of its residuals that contribute to crop production beyond a single season, as well as its eco-friendliness, organic fertilizer surpasses other soil fertility management tactics in benefits.

• The utilization of organic fertilizer not only enhances the quality of soil but also plays a pivotal role in reducing the impact of climate change by boosting carbon sequestration and enhancing the nutrient usage efficiency of crops.

• Moreover, the usage of organic fertilizers plays a crucial part in promoting sustainability in agriculture by enhancing the overall physical, chemical, and biological properties of the soil.

• The utilization of organic fertilizer was greatly impacted by the determinant aspects.

Acknowledgments

The authors are thankful to the anonymous reviewers for their comments and suggestions to improve the quality of this review paper. This review chapter was carried out as part of the Ph.D. research work of the first author.

Author contributions in writing review and editing

Habtamu Tadele performed the literature search and drafted and/or critically revised the work. Birtukan Amare revised the draft proposal and corrected reviewed the article after reviewers’ comments.

Data availability statement

All data generated or analyzed during this review are included in this published article.

Statements and declarations

The authors declare no conflict of interest.