Keywords:

Organic fertilizers

Composting

Soil restoration

Physicochemical evaluation of humus and compost as a strategy to strengthen sustainable

agriculture

Evaluación sicoquímica de humus y compost como estrategia para fortalecer la agricultura

sostenible

Avaliação físico-química do húmus e composto como estratégia para fortalecer a agricultura

sustentável

Dennis Renato Manzano Vela*

Vicente Javier Parra León

Susana Monserrat Zurita Polo

Máyuri Viviana Pico Gordón

Rev. Fac. Agron. (LUZ). 2025, 42(3): e254236

ISSN 2477-9407

DOI: https://doi.org/10.47280/RevFacAgron(LUZ).v42.n3.VII

Crop production

Associate editor: Dra. Evelyn Pérez Pérez

University of Zulia, Faculty of Agronomy

Bolivarian Republic of Venezuela

Recursos Naturales Renovables. Facultad de Recursos

Naturales. Escuela Superior Politécnica de Chimborazo

(ESPOCH); 060119, Ecuador.

Received: 13-05-2025

Accepted: 15-07-2025

Published: 03-08-2025

Abstract

Soil degradation due to unsustainable anthropogenic

management has generated the deterioration of its quality and health,

for this reason alternatives such as the use of organic fertilizers are

sought for the rehabilitation of its ecological functions. Therefore,

the present study evaluated the physical-chemical properties of

humus and compost produced at the Tunshi experimental station,

Chimborazo, Ecuador, in order to validate their suitability for

sustainable agriculture. Formulations based on local inputs were

used, including guinea pig manure, plant residues, green manure, and

rice husks. The analyses included parameters such as pH, electrical

conductivity (EC), organic matter (OM) and macronutrients,

following the Ecuadorian standard NTE INEN 211:1998 and the

INIAP technical manual. The results revealed that the compost and

humus formulations comply with quality standards, highlighting

the F2 compost formulation and the H2 formulation for humus

with their high total nitrogen and OM content. The compost (F3)

and humus (H3) formulations showed higher levels of phosphorus

and potassium, although with lower nitrogen content, where F2 (35

% guinea pig manure, 25 % green manure) and H2 (50 % guinea

pig manure, 50 % plant residues) showed higher nitrogen and

OM content, while in F3 (25 % guinea pig manure, 30 % green

manure) and H3 (40 % guinea pig manure, 60 % plant residues),

there were no signicant dierences in the parameters of the humus

formulations. These fertilizers represent a viable and sustainable

agroecological alternative for the rehabilitation of degraded soils.

This scientic publication in digital format is a continuation of the Printed Review: Legal Deposit pp 196802ZU42, ISSN 0378-7818.

Rev. Fac. Agron. (LUZ). 2025, 42(3): e254236 July-September. ISSN 2477-9409.

2-6 |

Resumen

La degradación del suelo por la gestión antropogénica insostenible

ha generado el deterioro de la calidad y salud del mismo, por éste

motivo se buscan alternativas como el uso de abonos orgánicos para

la rehabilitación de sus funciones ecológicas. Por ello, el presente

estudio evaluó las propiedades físico-químicas del humus y del

compost producidos en la estación experimental Tunshi, Chimborazo,

Ecuador, con el n de validar su idoneidad para la agricultura

sostenible. Se emplearon formulaciones basadas en insumos locales,

incluyendo estiércol de cuy, restos vegetales, abono verde y cascarilla

de arroz. Los análisis incluyeron parámetros como pH, conductividad

eléctrica (CE), materia orgánica (MO) y macronutrientes, siguiendo la

normativa ecuatoriana NTE INEN 211:1998 y el manual técnico del

INIAP. Los resultados revelaron que las formulaciones de compost

y humus cumplen con los estándares de calidad, destacándose la

formulación F2 de compost y la formulación H2 para humus con

su alto contenido de nitrógeno total y MO. Las formulaciones de

compost (F3) y humus (H3) mostraron niveles superiores de fósforo

y potasio, aunque con menor contenido de nitrógeno, donde F2 (35

% estiércol de cuy, 25 % abono verde) y H2 (50 % estiércol de cuy,

50 % restos vegetales) mostraron mayor contenido de nitrógeno y

MO, mientras que en F3 (25 % estiércol de cuy, 30 % abono verde)

y H3 (40 % estiércol de cuy, 60 % restos vegetales), no existieron

diferencias signicativas en los parámetros de las formulaciones

de humus. Estos abonos representan una alternativa agroecológica

viable y sostenible para la rehabilitación de suelos degradados.

Palabras clave: abonos orgánicos, compostaje, restauración de

suelos.

Resumo

A degradação do solo pela gestão antropogênica insustentável

tem gerado a deterioração da qualidade e saúde do mesmo, por este

motivo se buscam alternativas como o uso de adubos orgânicos para

a reabilitação de suas funções ecológicas. Por isso, o presente estudo

avaliou as propriedades físico-químicas do húmus e do composto

produzidos na estação experimental Tunshi, Chimborazo, Equador,

com o m de validar sua idoneidade para a agricultura sustentável.

Foram empregadas formulações baseadas em insumos locais,

incluindo esterco de cobaia, restos vegetais, adubo verde e casca de

arroz. As análises incluíram parâmetros como pH, condutividade

elétrica (CE), matéria orgânica (MO) e macronutrientes, seguindo

a normativa equatoriana NTE INEN 211:1998 e o manual técnico

do INIAP. Os resultados revelaram que as formulações de composto

e húmus cumprem com os padrões de qualidade, destacando-se a

formulação F2 de composto e a formulação H2 para húmus com seu

alto conteúdo de nitrogênio total e MO. As formulações de composto

(F3) e húmus (H3) mostraram níveis superiores de fósforo e potássio,

embora com menor conteúdo de nitrogênio, onde F2 (35 % esterco

de cobaia, 25 % adubo verde) e H2 (50 % esterco de cobaia, 50 %

restos vegetais) mostraram maior conteúdo de nitrogênio e MO,

enquanto que em F3 (25 % esterco de cobaia, 30 % adubo verde)

e H3 (40 % esterco de cobaia, 60 % restos vegetais), não existiram

diferenças signicativas nos parâmetros das formulações de húmus.

Estes adubos representam uma alternativa agroecológica viável e

sustentável para a reabilitação de solos degradados.

Palavras-chave: Fertilizantes orgânicos, compostagem, restauração

do solo.

Introduction

Soil quality and health is a crucial factor for agricultural

sustainability, as it not only supports food production but also plays

a fundamental role in the balance of ecosystems and agroecosystems

(Hameed Ologunde et al., 2024). Fertile soils allow optimal plant

development, which is essential for ensuring global food security

(Kuria et al., 2019). However, in recent decades, the increase in the

indiscriminate use of agrochemicals has generated signicant negative

impacts on soil health, currently one-third of the world’s soils are

in some process of degradation, and in Ecuador it is considered 50

% (Potthast et al., 2010; Sánchez-Cortez, 2019). This phenomenon

includes the progressive decrease in fertility, loss of organic matter,

increased salinity, and deterioration of its physicochemical properties

(Jiménez et al., 2024; Manzano Vela, et al., 2024a). These eects

not only aect agricultural productivity but also soil biodiversity and

surrounding water resources (Kleemann et al., 2022). Faced with

this problem, the need for sustainable alternatives that minimize

environmental impact and promote rational management of natural

resources has been raised (Dengiz et al., 2024; Manzano Vela et al.,

2024b). Among these alternatives, the use of organic fertilizers, such

as humus and compost, has emerged as an agroecological solution

with great potential for soil regeneration and promotion of sustainable

agricultural practices (Awoonor et al., 2025).

Various studies have documented the broad benets of organic

fertilizers in soil management (Ziajahromi & Leusch, 2022).

These amendments improve soil structure, increase its water

retention capacity, enhance microbial activity, and facilitate carbon

sequestration, key factors for maintaining a healthy agroecosystem

(Wen et al., 2025). They also provide essential nutrients such

as nitrogen, phosphorus, potassium, calcium, and magnesium,

fundamental for plant development (Bonilla-Bedoya et al., 2023).

Unlike chemical fertilizers, which can cause contamination problems

in soils, groundwater, and rivers, organic fertilizers represent an

environmentally responsible alternative (Amoah-Antwi et al.,

2020). This approach contributes to the mitigation of pollution and

rehabilitation of degraded soils while supporting the production of

healthy food (Adetunji et al., 2020). According to recent research,

the preparation of humus and compost using local inputs such as

plant residues and manure is not only an economical option for

farmers but also constitutes an eective strategy to strengthen food

security and sovereignty, reduce waste, and conserve ecosystems and

agroecosystems (Bünemann et al., 2018).

In this context, the Bio-Knowledge Centre of the Tunshi

Experiment Station presents an ideal environment to evaluate

the potential of organic fertilizers in sustainable agriculture

(Bhattacharya et al., 2024). However, despite local initiatives

oriented towards agroecology, there is insucient information about

the physicochemical properties of fertilizers produced in the region or

their adequacy to national and international technical standards (Rani

et al., 2023). Therefore, scientically evaluating these fertilizers

will not only validate their suitability but also identify necessary

improvements to optimize their production and promote their

replicability in other areas of the country and region (Eijsackers &

Maboeta, 2023).

This scientic publication in digital format is a continuation of the Printed Review: Legal Deposit pp 196802ZU42, ISSN 0378-7818.

Manzano et al. Rev. Fac. Agron. (LUZ). 2025, 42(3): e254236

3-6 |

Based on the above, the present study aims to analyze the

physical-chemical composition of humus and compost produced in

Tunshi, in order to demonstrate that replicable formulations at eld

scale constitute a viable resource for sustainable soil management

Materials and methods

Location of the study

The study, conducted in the rainy and dry seasons of 2023 at the

Bio-Knowledge Centre of the Tunshi Experimental Station, belonging

to the Escuela Superior Politécnica de Chimborazo (ESPOCH),

located in the Licto parish, Riobamba canton, Chimborazo province

(1°45’01.7’’ S 78°37’35.4’’ W, 2,840 m.a.s.l). The climate is

temperate-cold with an average annual precipitation of 738 mm,

average temperature of 12.9 °C and relative humidity close to 82 %.

The area is part of the Chambo river sub-basin, whose water network

denes the hydroedaphological dynamics of the environment.

At the same time, the physicochemical determinations of humus

and compost were carried out in the Soil and Chemistry Laboratories

of the Faculty of Natural Resources (ESPOCH), equipped with

reference instruments and standardized procedures for the analyses.

Preparation of humus and compost

The production of both organic fertilizers was carried out in

accordance with the Ecuadorian Technical Standard NTE INEN

211:1998 and the technical manual of the National Institute of

Agricultural Research (INIAP) (Feicán Mejía, 2011), using guinea

pig manure, green manure, horticultural residues and rice hulls as

structuring material. The inputs were shredded (< 5 cm), homogenized

and arranged in piles of 1.5 × 1.0 × 1.0 m. The piles were turned

weekly during the rst month and biweekly afterwards, maintaining

humidity with light irrigation; the thermophilic phase culminated at

30 days and maturation at 90 days, when the internal temperature

stabilized ≤ 5 °C above ambient and the pH approached neutrality.

For the humus, the pre-composted mixture was transferred

to vermicomposting beds (0.8 × 3 m) inoculated with 1 kg.m⁻² of

Eisenia foetida. The beds were covered with agricultural mesh and

maintained at 70 - 80 % humidity and 18 - 25 °C. After 60 days, the

vermicompost was sieved at 2 mm to separate the earthworm and

obtain the humus, subsequently stabilizing it for 10 days in permeable

sacks before its physicochemical characterization.

Physicochemical analyses

The analyses for the determination of physicochemical

parameters were carried out according to the following protocols;

pH was determined in a 1:2.5 fertilizer-water suspension following

NTE INEN 221:1997, using an potentiometer (Orion 720A+, Thermo

Electron Corp., USA); electrical conductivity was measured in the

same suspension with a conductivity meter (YSI 30, YSI Inc., USA).

Organic carbon was quantied by the Walkley-Black method (ISO

14235:1998) (International Organization for Standardization [ISO],

1998) using a digester-titrator (VELP DK 6, VELP Scientica, Italy),

while total nitrogen was obtained by Kjeldahl (ISO 11261:1995)

(ISO, 1995) with a distiller (Kjeltec 2100, Foss Tecator, Sweden);

from these values the C:N ratio was calculated as an indicator of

stability and maturity. Available phosphorus was determined by

UV-Visible spectrophotometry (ISO 11263:1994) (ISO, 1994) in

a spectrophotometer (Shimadzu UV-1601, Japan), and calcium

and magnesium contents were analyzed by atomic absorption

spectrophotometry (AOAC 978.02) (Association of Ocial

Analytical Chemists [AOAC], 1984) (PerkinElmer AAnalyst 200,

USA). All instruments were calibrated with certied reference

materials and the tests were performed in triplicate in the Soil and

Chemistry Laboratories of the Faculty of Natural Resources of the

Escuela Superior Politécnica de Chimborazo.

Statistical design and analysis

The experimental design included six treatments: three of compost

(F1, F2, and F3) and three of humus (H1, H2, and H3). Each treatment

underwent three repetitions, forming a total of 18 experimental units

(9 for compost and 9 for humus), seeking to guarantee the consistency

and reproducibility of the data (table 1).

Table 1. Combinations of inputs in the elaboration of compost

(F) and humus (H) for the formulation of treatments.

Chimborazo, Ecuador.

Ingredient / Input

F1 F2 F3 H1 H2 H3

Proportion (%)

Rice husk

40 30 35 – – –

Guinea-pig manure

30 35 25 60 50 40

Green manure*

20 25 30 – – –

Vegetable scraps

10 10 10 – – –

Plant remains

– – – 40 50 60

All formulations present their values as percentage values on a

wet basis, and all humus formulations were processed with a constant

density of 500 worms (Eisenia foetida) per kilogram of material.

These proportions were designed prioritizing inputs available

within the study locality, the relevance to their utilization, and the

reproducibility of the production process in communities and regions

with similar conditions. The statistical analysis was performed using

one-way ANOVA to compare the six treatments, each with three

repetitions. After conrming normality and homogeneity of variances

(Shapiro-Wilk and Levene tests, respectively), The Tukey test (α=

0.05) was applied exclusively to the parameters whose ANOVA was

signicant; for the humus variables, no signicance was detected, so

no post-hoc comparison was performed

Results and discussion

Physical analysis of the compost and humus formulations

revealed numerical dierences in pH, electrical conductivity (EC),

and organic matter (OM) content as shown in table 2. Nevertheless,

one-way ANOVA followed by Tukey’s post-hoc test (p<0.05)

showed that none of these three physicochemical parameters diered

signicantly among either the composts or the humus treatments.

Regarding chemical composition, the formulations displayed distinct

proles of essential macronutrients; statistical analysis (p≤0.05)

detected specic variation patterns, particularly for phosphorus (P)

and potassium (K). The F2 recorded pH the numerically highest value

(8.01±0.05), attributable to the 35 % guinea pig manure in its mixture.

All treatments remain within the optimal range for most crops (6.5-

8.5) (Wang et al., 2019).

The EC values of the evaluated composts ranged between 5.28

± 0.05 and 5.40 ± 0.04

mS.cm⁻¹, well below the salinity threshold

of 8 mS.cm⁻¹ recommended for organic amendments intended

for agricultural use (Yang et al., 2024). Consequently, treatments

F1, F2 and F3 can be considered suitable even for application in

agroecosystems with a tendency to salinization, without risk of ionic

toxicity for crops.

This scientic publication in digital format is a continuation of the Printed Review: Legal Deposit pp 196802ZU42, ISSN 0378-7818.

Rev. Fac. Agron. (LUZ). 2025, 42(3): e254236 July-September. ISSN 2477-9409.

4-6 |

Table 2. Mean values of physical and chemical analysis of humus and compost simples, Chimborazo, Ecuador.

Parameter Unit

Compost Humus

F1 F2 F3 H1 H2 H3

(Mean ± SD)

pH – 7.96±0.04 8.01±0.05 7.92±0.03 7.35±0.05 7.40±0.04 7.30±0.03

EC mS.cm⁻¹ 5.32±0.06 5.28±0.05 5.40±0.04 2.26±0.05 2.31±0.06 2.20±0.05

MO % 11.46±0.05 11.50±0.06 11.40±0.04 10.53±0.05 10.60±0.05 10.50±0.04

N total % 0.57±0.01 0.58±0.01 0.56±0.01 0.53±0.01 0.54±0.01 0.52±0.01

P % 0.60±0.02 0.62±0.02 0.58±0.02 0.09±0.01 0.10±0.01 0.08±0.01

K % 1.20±0.02 1.22±0.02 1.18±0.02 1.35±0.02 1.37±0.02 1.33±0.02

Ca % 2.40±0.02 2.42±0.02 2.38±0.02 0.64±0.01 0.65±0.01 0.63±0.01

Mg % 0.99±0.02 1.01±0.02 0.97±0.02 0.11±0.01 0.12±0.01 0.10±0.01

n: 3, EC: electric conductivity, SD: standard deviation.

In humus, the contents of P (0.09 ± 0.01 % - 0.10 ± 0.01 %) and

K (1.33 ± 0.02 % - 1.37 ± 0.02 %) were lower than in composts

(p≤0.05 inter-group), due to the partial loss of soluble salts during the

vermicomposting process (Antonangelo et al., 2021). The ANOVA

indicated that the concentrations of N, P, K, Ca and Mg did not dier

signicantly between the humus treatments H1, H2 and H3 (p>0.05,

in all cases); therefore, none can be considered statistically “superior”

in the contribution of macronutrients. However, descriptively,

the formulation with 50 % plant residues (H2) presented slightly

higher values of P and K, a trend consistent with studies that report

faster mineralization when the plant fraction approaches a 1:1 ratio

with manure (Ebrahimi et al., 2024; Niedrite et al., 2024; Wang

et al., 2025; Feng et al., 2024; Wang et al., 2019). Although these

dierences do not reach statistical signicance, they suggest that a

higher content of plant matter could favor the initial availability of

certain macronutrients.

However, such a trend should be conrmed with larger batches or

a factorial design that modies the proportion of inputs more broadly.

Despite numerical variations, all formulations met the optimal ranges

of N (> 0.5 %), P (> 0.08 %), and K (> 1.2 %) for organic amendments

for agricultural use (Vaz-Moreira et al., 2025; Tao et al., 2024).

In humus, the lower EC and higher microbial stability oer

advantages for crops sensitive to salinity, while compost, with slightly

higher NPK, may be preferred in low-fertility loam soils (García-

Rández et al., 2025). The Tukey test (table 3) revealed signicant

dierences (p<0.05) among compost formulations for total N, P, K,

and OM, while no signicant dierences were found for pH and EC.

Table 3. Tukey’s multiple comparisons for physicochemical

parameters of compost formulations, Chimborazo,

Ecuador.

Parameter

F1 F2 F3

(Mean ± SD)

7.96 ± 0.04 a 8.01 ± 0.05 a 7.92 ± 0.03 a

EC (ms.cm

-1

)

5.32 ± 0.06 a 5.28 ± 0.05 a 5.40 ± 0.04 a

N total (%)

0.57 ± 0.01 ab 0.58 ± 0.01 a 0.56 ± 0.01 b

P (%)

0.60 ± 0.02 ab 0.62 ± 0.02 a 0.58 ± 0.02 b

K (%)

1.20 ± 0.02 ab 1.22 ± 0.02 a 1.18 ± 0.02 b

OM (%)

11.46 ± 0.05 ab 11.50 ± 0.06 a 11.40 ± 0.04 b

Note: Values with dierent letters in the same row indicate statistically signicant dierences

(p<0.05) according to Tukey’s test,n: 3, EC: electric conductivity, SD: standard deviation.

For OM, F2 (11.50 ± 0.06 %) signicantly exceeded (p≤0.05) F3

(11.40 ± 0.04 %), while F1 (11.46 ± 0.05 %) showed an intermediate

value that did not dier signicantly from either F2 or F3, a result

explained by the higher combined proportion of guinea pig manure

(35 %) and green manure (25 %) which provides easily degradable

compounds (Naderi-Boldaji & Keller, 2016). The 5 % dierence in

manure fraction between formulations was not sucient to alter OM

in a statistically relevant manner between F1 and F3, conrming the

greater incidence of green manure as a determining factor.

In humus the pH values remained stable (7.30 ± 0.03 - 7.40 ± 0.04)

suggesting that the regulatory activity of worms buers alkalinization

(AL-Kayssi, 2021).

EC was signicantly lower than in composts and also showed no

internal dierences (2.20 ± 0.05 - 2.31 ± 0.06 mS.cm⁻¹), partly due to

salt excretion via calciferous glands during vermicomposting (Serri

et al., 2022).

OM varied between 10.50 ± 0.04 % (H3) and 10.60 ± 0.05 %

(H2) without signicant dierences (p>0.05), consistent with the

high eciency of stabilization and humication characteristic of the

process (Vasu et al., 2024). Although composts presented slightly

higher OM and moderately higher EC than humus, inter-process

dierences were statistically signicant only for EC and OM (p≤0.05),

while pH remained comparable (p>0.05). This evidence shows

that vermicomposting reduces nal salinity without compromising

organic carbon stability, thus oering a bioproduct for sensitive crops

(Satriani et al., 2024).

For compost the concentrations of N, P, and K ranged, respectively,

between 0.56 ± 0.01 % - 0.58 ± 0.01 %, 0.60 ± 0.02 % - 0.62 ± 0.02

%, and 1.20 ± 0.02 % - 1.22 ± 0.02

%, coincident ranges reported in

the literature (Yin et al., 2021; Kong et al., 2024; Reyes-Torres et al.,

2018).

Although F2 showed numerically higher values, ANOVA indicated

absence of signicant dierences among the three formulations

(p>0.05). This conrms that the 5 % increase in guinea pig manure

and green manure was not sucient to modify the availability of

macronutrients in a statistically relevant manner, coinciding with

reports where variations ≤ 10 % in the animal fraction generate

minor changes in NPK (Faverial et al., 2016; Wang et al., 2025).

Nevertheless, the slight upward trend suggests that the combination

of nitrogen-rich manure and leguminous green manure favors nutrient

stabilization during composting, an aspect that could acquire greater

importance in mixtures with a higher proportion of lignocellulosic

residues (Chen et al., 2024).

This scientic publication in digital format is a continuation of the Printed Review: Legal Deposit pp 196802ZU42, ISSN 0378-7818.

Manzano et al. Rev. Fac. Agron. (LUZ). 2025, 42(3): e254236

5-6 |

F2 had the highest pH, P, and K, attributed to a balanced mix of

plant and animal residues that enhances mineralization and nutrient

availability. Meanwhile, F3 exhibited the highest EC. A slightly

alkaline pH, as in F2, is known to improve phosphorus and potassium

solubilization (Sánchez et al., 2017).

F2 stood out in its total nitrogen content and OM, slightly

surpassing F1 and F3. This advantage is attributed to the higher

proportion of guinea pig manure and green manure, which promote a

more balanced C/N ratio during the composting process. Meanwhile,

the estimated average C/N ratios were 21:1 in F1, 19:1 in F2, and

22:1 in F3. The higher organic matter content in F2 demonstrates its

potential to improve soil structure and promote moisture retention (Li

et al., 2024).

From an agronomic perspective, it would be important to

consider whether these dierences, although statistically signicant,

have practical relevance under eld conditions. Future studies

could evaluate whether these slight variations in physicochemical

parameters translate into measurable dierences in plant growth or

soil quality.For humus, one-way ANOVA revealed no statistically

signicant dierences (p>0.05) among formulations for any of the

physicochemical parameters evaluated consequently, a Tukey post-

hoc test was not applied.

Regarding humus, there is a nutrient dynamic in vermicomposting,

as the worms decompose the organic matter and homogenize the

nutrients (Domínguez & Gómez-Brandón, 2013).

These results conrm that, despite minor numerical variations, the

three vermicomposts provide comparable nutrient availability and do

not present organic-matter limitations.

Conclusions

Physicochemical evaluations of compost and humus formulations

conrm their usefulness as organic amendments for sustainable

agriculture. The observed variations in pH, EC, organic matter, and

macronutrients are related to the type of input in the formulation,

considering the easy acquisition and replicability for the generation

of these fertilizers. In the compost, formulation F2, enriched with 35

% guinea pig manure and 25 % green manure, stood out for its higher

content of total N (0.58 ± 0.01 %), P (0.62 ± 0.02 %), K (1.22 ± 0.02

%), pH (8.01 ± 0.05) and organic matter (11.50 ± 0.06 %), making it

an ideal option for nutrient-decient soils. In contrast, F3 registered

the highest electrical conductivity (5.40 ± 0.04 mS.cm⁻¹), which

could be benecial for crops tolerant to salinity.

Regarding humus, H2, with a balance between guinea pig manure

(50 %) and plant residues (50 %), showed the highest concentrations

of total N (0.54 ± 0.01 %), P

(0.10 ± 0.01 %), K (1.37 ± 0.02 %)

and organic matter (10.60 ± 0.05 %), positioning itself as the most

suitable alternative to increase soil fertility and plant development.

These formulations comply with Ecuadorian regulations and INIAP

standards, validating their potential for sustainable soil management.

Local replication, taking advantage of available inputs and appropriate

methodologies, favors the adoption of agroecological practices.

However, strict control of production parameters and variability in

inputs is recommended to ensure consistent quality of the fertilizers.

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AL-Kayssi, A.W. (2021). Use of water retention data and soil physical quality

index S to quantify hard-setting and degree of soil compactness indices

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