





























1 

 

In ternationa l
Scholars
Journa ls

 

African Journal of Pig Farming ISSN: 2375-0731 Vol. 11 (2), pp. 001-011, February, 2023. Available online at 
www.internationalscholarsjournals.org © International Scholars Journals 

 

Author(s) retain the copyright of this article. 
 
 

 

Full Length Research Paper 

 
Grass production Tifton 85 and nutrient extraction with 

swine wastewater doses 
 

Vinícius de Oliveira Rezende1*, Luís César Dias Drumond2, André Mundstock Xavier de 
Carvalho2, Regina Maria Quintão Lana3 and Marcos Vieira de Faria3

 
 

1
Department of Agronomy, Federal University of Viçosa, Brazil. 

2
Council for Teaching, Research and Extension-Rio 

Paranaíba Campus. Federal University of Viçosa, Highway BR 354 - km 310 (at 1,300m) 38810-000 - Rio Paranaiba, 

MG – Brazil. 
3
Department of Agronomy, Federal University of Uberlândia – UFU, Brazil. 

 
Accepted 13 November, 2022 

 
Swine wastewater (SW) is considered as a source of nutrients for agriculture. The quantities and frequencies 
applied may vary according to the soil class, the nature and composition of the waste, the climatic conditions 
and the cultivated plant species. Therefore, this study aimed to evaluate the effects of application of five 
Swine wastewater doses (0, 500, 1000, 2000 and 2500 m³ ha

-1
) in the production of components and grass 

nutrient extraction Tifton 85 and changes in soil chemical properties after the end of the last application of 
swine wastewater. To achieve these goals, we evaluated the quantities of extracted nutrients, density and 
height of the pre-grazing grass, forage accumulation rate and carrying capacity. The experimental design was 
a randomized block. The production of dry matter was 18159.80 kg ha

-1
, and the average height of 85 Tifton 

was 34.83 cm. The higher carrying capacity, 10 AU ha
-1

 was obtained with the dosage of 2500 m³ ha
-1

. While, 
the dose of 2000 m³ ha

-1
 supplied the nutritional needs of Tifton 85 in nitrogen, potassium, calcium, 

magnesium, copper, iron, zinc and boron. The quantities of extracted nutrients (kg ha
-1

) at grass Tifton 85 
grazed were: N = 405.14; P = 57.77; K

+
 = 387.69; Ca

2+
 = 77.05; Mg

2+
 = 49.68; S-SO4

-2
 = 31.48; B = 0.33; Cu

2+
 = 

0.20; Fe = 2.88; Mn
2+

 = 4.61; Zn
2+

 = 2.86. The application of increasing doses of SW promoted a linear increase 
in grass production components Tifton 85, as well, promoted changes in soil chemical properties and 
quantities of extracted nutrients. 
 
Key words: Pasture, liquid waste, nutrient extraction, plant growth.  

 
 
INTRODUCTION 

 
Brazilian swine production is increasing annually in order 
to meet both domestic and foreign market demand with 
regard to the quality of raw materials and environmental 
care (Pinto et al., 2014). Brazil is the fourth largest  

 
 
 
 

 
producer of pork in the world, this represents the 
equivalent of 3.7 million tonnes of pigs (EMPRAPA, 
2017). The main problem of this activity, therefore, is the 
generation of enormous quantities of manure that can  
  

*Corresponding author. E-mail: msc.vinicius@gmail.com.  
 
Author(s) agree that this article remain permanently open access under the terms of the Creative Commons Attribution 

License 4.0 International License  



2 

 

 
 
 

 

corroborate to the pollution of terrestrial and aquatic 
ecosystems (Segat et al., 2015).  

The fertilization of crops with swine wastewater is a 
common practice and is attractive for the reduction of 
natural resources and environmental pollution control. 
The feasibility of such use is due to the large volume of 
waste generated and the amount of nutrients that are 
easily mineralized when applied in soil (Lucas et al., 
2013).  

In this sense, an alternative that has been highlighted in 
the pursuit of sustainability in the recovery of degraded 
cultivated soils and pastures is the use of organic 
fertilizers or cover crops because the mineral fertilizers in 
this context is rather low due to its high cost and due to 
the low purchase power of most producers. For instance, 
mineral fertilizers in Africa cost at the farm gate, two to six 
times as much as in Europe, North America, or Asia 
(Sanchez, 2002). Therefore, organic inputs are a viable 
alternative source of plant nutrients for resource-poor 
farmers. Application of organic input usually leads to 
increased crop yields and pasture (Ogundare et al., 2012; 
Matthews, 2017). The acceptance by local farmers of the 
benefits of compost to the soil and crops would be a 
significant incentive to reduce the expensive mineral 
fertilizers and optimize their use (Azim et al., 2017). Thus, 
the use of SW is available as an alternative to replace the 
mineral fertilizer, demonstrating its efficiency in dry matter 
production and nutrient availability (Zanine and Ferreira, 
2015; Gomes et al., 2017; Lucas et al., 2013). However, 
there is little information regarding the use of this waste in 
areas with degraded pastures (Fogel et al., 2013).  

The supply of nutrients in adequate amounts via SW 
can increase the nutritional quality of the forage, 
enhancing performance and/or animal productivity 
(Assmann et al., 2009). Therefore, the use of Swine 
wastewater (SW) as a source of nutrients in pasture 
areas is presented as an alternative to disposal of this 
waste (Assmann et al., 2009; Seidel et al., 2010). 
Camargo et al. (2011) observed the effects of different 
doses of swine manure on forage Tifton 85 and found 
that an increase in dry matter production and P content 
grew linearly with the doses, thus suggesting a dose of  

100 m³ ha
-1

 to obtain about 3500 kg ha
-1

 dry weight in a 

period of 28 days. Serafim and Galbiatti (2012) discussed 
that an increase in the application of swine waste 
increased the supply of nitrogen and phosphorus to the 
soil, thus promoting plant growth and increasing the ratio 
of leaf/stem.  

Thus, it is needed to find the proper management from 
a biophysical point of view to promote sustainable 
agriculture. However, it is also necessary that farmers 
accept new strategies that propose cultural and technical 
shifts (Cerdà et al., 2018a). The search for information 
and knowledge to clarify how to use the SW in pastures is 
growing. To have a correct land management in intensive 
systems, it is important to know the nutrient extraction 
capacity for forage to mitigate the negative 

 
 
 
 

 

environmental impacts on the ground and to define the 
best application rates.  

In this way, there is a need to design proper policies to 
achieve sustainability, and for this, the scientific 
community should produce information in collaboration 
with land managers and other actors, which will guide 
policy makers to implement the most efficient 
managements and strategies (Cerdà et al., 2018b). This 
study aimed to evaluate the effects of application of five 

SW doses (0, 500, 1000, 2000 and 2500 m³ ha
-1

) in the 

following production components: bearing capacity, dry 
matter yield, density, percentage of dry matter grass 
height, dry matter production per day and in grass 
nutrient extraction Tifton 85 grazed and changes in soil 
chemical properties. 

 

MATERIALS AND METHODS 
 
Study area 
 
The study was conducted during the period from January to April, 
2013, at the Bonsucesso farm, which is located in, Minas Gerais 
state, Brazil, at the geographical coordinates 19°05'17"S and 
48°22'00"W, at an altitude of 820 m, at an dystrophic yellow Oxisol, 
according to Embrapa classification in 2006. According to the 
Köppen and Geiger (1928) system, the climate is characterized as 
Aw (typical tropical, with average rainfall around 1600 mm per year, 
with moderate water deficit in winter and excessive rain in summer). 
Before the experiment installation, it was determined that the 
chemical and physical soil characteristics of the area at different 
depths of 0.00-0.20 m and 0.20-0.40 m (Table 1). For this, 10 soil 
samples to form a composite sample were collected at random in 
the experimental area with a Dutch auger. 
 

The study was conducted on grazing Tifton 85 and was installed 
five years ago. The experimental design was a randomized 
complete block design with five treatments and three replications. 
Plots were 3 x 3 m, amounting 9 m², 1 m boundary among plot. The 
treatments consisted of the following wastewater doses of swine 
(SW): control (without application of SW), 500, 1000, 2000 and 

2500 m³ ha
-1

. The waste used in the experiment comes from a 
swine production system in the finishing phase, handled with 
biodigester PVC blanket and stabilization pond, being stored for 
about 20 days. After this period, the SW is applied in the grazing 
areas. There was the uniform grass height of Tifton 85, 0.10 m tall, 
with hydraulic brush cutter before the start of the experiment. After 
the treatments (Table 2) and data collection (21 day cycle), the 
remaining forage of each cycle was quantified and grazed up to a 
height of 0.10 m.  

The application doses of SW were performed manually with a 1-
inch diameter hose and distributed evenly over each plot. The 
doses were calculated due to the application of time on each plot. 

Thus, the flow rate was set at 45 L min
- 1

 and application times 
were 0 (no application), 2, 4, 8 and 10 min, respectively providing 
from the lower treatment dose to the higher dose. Each dose of SW 
was split into five applications, always at the beginning of each 21-
day grazing cycle (Table 2). This installment was not to exceed the 
field capacity in a single application. In each application date, they 
were collected a sample of 600 mL of SW and stored in refrigerator. 
The five SW samples were homogenized, then pulled out a sample 
that was sent to Araxá Environmental laboratory for chemical  
characterization. The average levels of nutrients are SW: N = 

823.60 mg L
-1

; P = 20.46 mg L
-1

; = K
+
 509.40 mg L

-1
; Ca

2+
 = 51.54 

mg L
-1

; Mg = 33.53 mg L
-1

; organic matter = 331.80 mg L
-1

, B = 0.55 



3 

 

  
 
 

 
Table 1. Chemical characteristics and grain size of the soil, in the depths studied the experimental area with the Tifton 85 grass before 
application of treatments. 
 

 Depth pH P resin K+ S-SO4
2-

 Ca2+ Mg2+ Al3+ H+Al 

 (m) (water) ............ mg dm
-
³............... .......................cmolc dm

-
³ ......................... 

 0.00-0.20 5.50 39.90 94.0 1.77 1.00 0.30 0.15 2.60 

 0.20-0.40 5.50 18.20 56.0 2.02 0.70 0.10 0.20 2.10 

          

  B Cu
2+

 Fe Mn
2+

 Zn
2+

 SB t T 

  .......................................... mg dm
-
³...................................  .............cmolc dm

-
³.......... 

 0.00-0.20 0.11 4.00 91.00 6.30 8.10 1.54 1.69 4.14 

 0.20-0.40 0.28 1.60 28.00 2.40 2.00 0.94 1.14 3.04 

          

  MO V m Clay  Silt  Sand 

  % % % ...................................... g kg
-
¹..................................  

 0.00-0.20 2.3 37 09 153  25  822 

 0.20-0.40 1.6 30 17 165  17  818  
Potassium (K) = (HCl 0.05 mol L

-1
 + H2SO4 0.0125 mol L

-1
); available P (resin); Ca, Mg, Al, (KCl 1 mol L

-1
); H + Al = (Buffer Solution - SMP pH 7.5); 

SB = Basic Sum; T = CEC at pH 7.0; V = Base saturation; m = saturation by aluminum; Organic matter (M.O.) = Colorimetric Method. Boron (B) = 

(0.0125% BaCl2.2H2O); Cu, Fe, Mn, Zn = (DTPA 0.005 mol L
-1

 + TEA 0.1 mol
-1

 CaCl2 0.01 mol L 
-1

 a pH 7.3). Clay: pipette method. Chemical 
analysis carried out according to methodologies described by Embrapa (2009). 
 
 

 
Table 2. Total dose of SW, portions of value applied to each treatment and dates of split applications in grass Tifton 85.  

 
 Dose total 05/01/13 26/01/13 16/02/13 09/03/13 30/03/13 

  ..................................................... m
3
 ha

-1
 ................................................  

 500 100 100 100 100 100 

 1000 200 200 200 200 200 

 2000 400 400 400 400 400 

 2500 500 500 500 500 500 
 
 

 

mg L
-1

; Cu
2+

 = 4.33 mg L
-1

; Fe = 6.34 mg L
-1

; Mn
2+

 = 0.91 mg L
-1

 

and Zn
2+

 = 5.71 mg L
-1

 and pH CaCl2 = 8.16. The methodologies 
used in determining the SW nutrients were based on Standard 
Methods for the Examination of Water and Wastewater (APHA, 
2012). During the experiment, the rainfall and average temperature 
were measured daily and are displayed by means of each ten-day 
period (Figure 1). For evaluation of forage growth, five successive 
cuts were performed (over 0.10 m high) in 21-day intervals (cycles). 
To collect the sample mass of dry (DM) forage, the sampling 
method square template, proposed by Aguiar (2009), was used.  

The forage harvested in the area sampled per plot were 
determined a fresh pasture mass. Subsequently, the identified sub-
samples were dried in an oven with forced air circulation at 65°C for 
72 h to determine the mass of dry matter over 0.10 m high 
(Gardner, 1986). The percentage of dry matter was then calculated 

and expressed in kg ha
-1

 DM. Then, soil samples were crushed 
(Willey mill) to determine the total content of nutrients. To determine 
the height of grass from the ground level to the highest part a top 
were used a scale and an x-ray paper were used to standardize the 
height of the plants, in 10 replications. The bulk density of forage 
was obtained by dividing the dry mass weight/height plants that was 

expressed in kg ha
-1

 cm
-1

. The forage accumulation was calculated 
by subtracting the herbage mass in pre-grazing forage by the post-
grazing mass. Forage accumulation rate (over 0.10 m) was 

expressed in kg ha
-1

 day
-1

 DM. It was calculated by dividing the 

 
 

 
accumulation of forage for 21 days grazing cycle by 21, the number 
of days in the cycle.  

The pasture's carrying capacity was calculated considering an 
herbage allowance of 5 kg DM per 100 kg live weight. After the 
measurements of pasture, the cattle were put to graze, aimed at 
standardizing the grass height to 0.10 m. After 21 days of 
application of the last installment of SW, soil samples were taken at 
different soil depths such as 0.00-0.20 m and 0.20-0.40, originating 
six samples, randomly collected in the plot with a Dutch auger. The 

pH in water, exchangeable acidity (Al
3+

), potential acidity (H + Al) 

and soil organic matter (OM), phosphorus (P), potassium (K
+
), 

calcium (Ca
2+

), magnesium (Mg
2+

) copper (Cu
2+

), zinc (Zn
2+

), 

manganese (Mn
2+

) and iron (Fe) was analyzed, according to the 
methodology described by EMBRAPA (2009).  

The aerial parts of the plants were subjected to analysis of the N, 
P, K, Ca, Mg, S, Fe, Cu, Mn, Zn, B according to methodologies 
EMBRAPA (2009) after each 21-day cycle. With the nutrient content 
of aerial parts of each cycle, the accumulation of these nutrients 
and recovery efficiency of each of the plant were evaluated. The 
accumulation of nutrients in the aerial part of each cycle was then 

used to define the nutrient uptake of the grazed pasture (kg ha
-1

) to 
105 days of experiment. All results were analyzed using the Barttlet 
and Jarque-Bera test (Jarque and Bera, 1980) to check the 
homogeneity of variances conditions and normality, respectively. 
Analysis of variance and regression 



4 

 

  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
Figure 1. Storm Precipitation and Average Temperature during the period experiment. 

 
 

 
analysis for the SW doses were carried out, to determine levels of 
significance, using the SAEG 9.1 program, 2007. 
 

 

RESULTS AND DISCUSSION 

 

The results of analysis of variance for the production of 
components are shown in Table 3. The application of 
different doses of SW provided a linear increase in all 
grass production components Tifton 85 studied (Figure 
2). The average heights of Tifton 85 ranged between 31 
and 39 cm with a 21-day cycle (Figure 2d). Results 
similar to the Aguiar (2009), an experiment in Uberaba, 
with intensive management, which found an average 
height in the spring/summer of 36.4 cm and an annual 
average of 29.7 cm.  

The higher carrying capacity, 10 AU ha
-1

 was obtained 

with the dosage of 2500 m³ ha
-1

, whereas grazing 
efficiency of 50% (Figure 2b). Lupatinie Hernandez 
(2006) showed, among various types of forage, the Tifton 
85 grass with high fertilization responded better to 

irrigation, with a carrying capacity of up to 10 AU ha
-1

. 
Which, showed the great forage production potential of 
grass associating intensive management, adequate 
fertilization and irrigation. The accumulation rate of dry 

matter per day obtained averages 138-219 kg ha
-1

 day
-1

 
(Figure 2e). Aguiar et al. (2005) showed an average 

annual accumulation rate of forage of 172 kg ha
-1

 day
-1

. 

 
 
 

 

Drummond et al. (2006) reached herbage accumulation 

rate of 148.2 kg ha
-1

 day
-1

 of dry matter in grazing Tifton 
85 fertilized with swine waste in the region of Uberaba - 
MG. Research works on pastures have presented linear 
increases of forage dry matter using doses of wastewater 
(Orrico junior et al., 2013; Andrade et al., 2014; Homem 
et al., 2016), with average accumulation doses of up to 

170 kg ha
-1

 day
-1

 of DM in Tifton 85 grass using swine 
wastewater (Andrade et al., 2014).  

Vielmo et al. (2011) used SW at doses of 0 to 320 m
3
 ha

-

1
, cycle of 28 days on Tifton 85, and verified a production of 

151 kg ha
- 1

 day
-1

 of dry matter at the highest dose. Gomes 

et al. (2018) obtained higher productivity, equal to 189 kg ha
-

1
 day

-1
 of dry matter using dose of 300 m

3
 ha

1
. Andrade et 

al. (2012) in an experimental area on the campus of Rio 
Paranaiba UFV evaluated the forage accumulation and 
managed in the intensive irrigated system. The ideal point of 
grazing and the chemical composition of forage produced in 
summer and autumn in pasture managed in intensive 
system with Tifton 85 grass found herbage accumulation 

rates of 140.0 kg ha
-1

 day
-1

 of DM in the summer and 122.2 

kg ha
-
  

1 day
-1

 of DM in the fall. The height of the ideal grass for 
grazing was 25.4 cm.

  

The highest production of dry matter was obtained with 

an average dose of 2500 m³ ha
-1

 (Figure 2a), which was
  

66. 5% higher than the average control, in the period of  
105 days. The  linear  increase  of production and  grass 



5 

 

  
 
 

 
Table 3. Averages of the components related to production Tifton 85 subjected to increasing doses of SW.  
 

Components of production Averages p-valor CV%  

Carrying capacity (UA ha
-1)

 

Production of dry matter (kg ha
-1)

 
-1 -1 

Density (kg ha  cm  of DM)  
Dry matter (%)  
Grass height (cm)  

Accumulation rate of dry matter per day (kg ha
-1)

 
 

  
 

7.69 0.000 5.90 

18159.80 0.000 5.90 

109.40 0.008 7.08 

23.39 0.058 3.15 

34.83 0.000 2.05 

172.95 0.000 5.90 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Figure 2. Components of production: production (kg ha
- 1

) (a) carrying capacity (b), density (c) of the grass 
height (d) and accumulation rate of dry matter per day (e) the trial period with the Tifton 85 grass, when 
subjected to increasing doses of SW. **: Significant at 1% probability. 



6 

 

 
 
 

 
Table 4. Average macro content, micronutrients and chemical characteristics of the soil subjected to increasing doses of SW.  

Depth Variable 

P resin K+ S-SO4
2-

 Ca2+ Mg2+ SB H+Al T 
 

............... 
mg dm

-3
 
 

............................... cmolc dm
-3

 
  

 

   ............ ............................  
 

 Averages 31.27 101.00 3.67 0.64 0.44 1.34 2.29 3.63 
 

0.00-0.20 m p-valor 0.385 0.468 0.011 0.230 0.034 0.092 0.594 0.344 
 

 C.V. % 58.97 22.62 39.83 24.71 22.92 17.82 14.07 10.67 
 

 Averages 7.16 102.00 4.87 0.43 0.26 0.95 1.75 2.7 
 

0.20-0.40 m p-valor 0.241 0.742 0.003 0.004 0.001 0.008 0.028 0.633 
 

 C.V. % 57.79 27.81 26.66 16.85 13.14 14.94 10.95 8.12 
 

          
 

  pH M.O. V B Cu
2+

 Fe Mn
2+

 Zn
2+

 
 

  (water) % %  .................................. mg dm
-3

 ........................ 
 

 Averages 5.49 1.69 36.82 0.10 3.10 54.40 7.22 5.27 
 

0.00-0.20 m p-valor 0.089 0.328 0.168 0.096 0.464 0.679 0.029 0.652 
 

 C.V. % 3.44 15.64 14.91 15.18 26.26 42.83 23.21 42.75 
 

 Averages 5.61 1.05 35.09 0.9 1.89 18.87 4.52 1.5 
 

0.20-0.40 m p-valor 0.003 0.906 0.003 0.977 0.725 0.313 0.015 0.463 
 

 C.V. % 4.17 12.76 13.22 22.32 64.97 26.21 24.81 31.38 
  

 
 

 
height influenced the dry matter density, which increased 

from 92.4 kg ha
-1

 cm
-1

 DM in witness to 125.2 kg ha
-1

 cm
-
 

1 DM at the highest dose (2500 m³ ha
-1

), an increase of
 

34. 5% in the grass density (Figure 2c). With increasing 

doses of the SW, the pH did not show any variation in the 

two depths (Tables 1 and 4), due to the alkaline 

characteristics of SW. According to the results this study, 

Silva et al. (2014) observed that soil attributes related to the 

acidity did not suffer influence of successive applications of 

SW. These differed from Queiroz et al. (2004) who observed 

a lowering of the pH with the application of SW. According to 

Bouwer (2000), in soils receiving wastewater, there may be 

a decrease in pH due to the mineralization of organic 

compounds of the SW, which facilitates the production of 

CO2 and organic acids. Already, Lucas et al. (2013) 

observed the pH  
increased from 5.47 to 6.77 in the soil (0 to 0.60 m) at 
1015 days of SW application. Increased pH values of soil 
were consistent with the high pH values of SW used, 
ranging from 7.08 to 7.70.  

The available potassium content (K
+
) in the soil was 

similar at both depths with 101.0 and 102.0 mg dm
-3

 
levels (Table 4) and fall within the adequate availability 
class, according to CFSEMG Ribeiro et al. (1999). A 

significant increase in K
+
 content at a depth of 0.20-0.40 

m, indicated a percolation of K
+
 for the deeper layers, 

because the soil characterization analysis before applying 
the SW doses (Table 1) the levels were 94.0 and 56.0 mg 

dm
-3

 in these depths. By being a monovalent, K
+
 has low 

retention on soil colloids, being susceptible to being 
leached from the surface layers for the subsoil layers. 
Which with the application of SW doses, the amount of 

 
 
 

 

added K
+
 was high than extracted by Tifton 85 (Figure 

3c), favoring an increase in the levels of K
+
 in the soil 

(Table 4).  
The potassium content of the soil increased in this 

experiment because when compost is used, according to 

Scherer (2001), the potassium K
+
 from the mineral and 

organic fertilizer are similar. Thus, there is no requirement 
to undergo any mineralization through the action of 
microorganisms.  

According to Penha et al. (2015) long-term applications 
of pig slurry in a Brazilian Cerrado soil have shown to 
affect chemical characteristics of the soil. High pig slurry 
rates increased P contents only in the soil surface, while 
the contents of K increased throughout the soil profile. 
This fact shows the marked difference in terms of P and 
K behaviors in tropical soils, indicating that K is more 
prone to be leached in a Cerrado soil following 
successive applications of pig slurry. The phosphorus (P) 
showed a higher concentration in the surface layer (Table 
4). This is because the positive organic radicals in SW 
adsorb P, favoring surface accumulation. Also the clay in 
these soils are sesquioxidic which feature high 
phosphorus adsorption. The P in Cerrado soils have low 
mobility focusing mainly in layers of 0.00 to 0.10 m. In a 
study on the use of swine wastewater in natural pasture, 
Ceretta et al. (2003) showed no changes in phosphorus 
concentration, with high concentration of P in the surface 
layer, with increases of 580% to 8.3 months and 6.710% 
at 48 months of application liquid effluent from pig farms. 
These studies indicate the importance of monitoring when 
performing constant application of SW in the same area. 



7 

 

   
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Figure 3. Extraction of the nutrients N (a), P (b), K (c), Ca (d) and Mg (e) by dry weight.  
** and *: significant at 1 and 5% probability, respectively. The dotted line refers to the addition of nutrients to the soil by 
increasing doses of SW and the continuous line for extracting the forage. 

 
 

 

However, Seganfredo et al. (2017), reports that the 
application of SW increases the ease of desorption of P 
and this makes it necessary to control its movement in 
the profile and transport through runoff. There was a 
significant effect of the SW application on the content of 

 
 
 

 

(Mg
2+

) available in soil (Table 4). According to Ribeiro et 
al. (1999), the levels observed in two depths remained 

low (0.44 and 0.26 cmolc dm
- 3

). However, there was a 

significant increase in Mg
2+

, in both evaluated depths, as 
in soil characterization analysis before applying the SW 



8 

 

 
 
 

 
Table 5. Medium of the leaf content of macro and micronutrients of Tifton 85 subjected to increasing doses of SW.  
 
 Element N P K S Ca Mg B Cu Fe Mn Zn 

  ................................. g kg
-1

...............................    .........................mg kg
-1

 ........................  

 Averages 22.62 3.12 21.28 1.69 4.18 2.66 18.11 11.19 151 242 144 

 p-valor 0.008 0.064 0.021 0.020 0.565 0.238 0.308 0.984 0.619 0.301 0.004 

 C.V. % 2.39 4.28 3.56 6.27 4.43 4.98 12.29 13.25 11.31 21.96 0.11 
 
 

 
doses (Table 1), the determined values were 0.30 and 

0.10 cmolcdm
-3

 at a depth of 0.00 to 0.20 and 0.20-0.40 
m, respectively. With the application doses of the SW the 

added amount of Mg
2+

 was higher than that extracted by 

Tifton 85 (Figure 3e), thus favoring the increase in Mg
2+

 

content in soil (Table 4). The content of calcium (Ca
2+

) at 

a depth of 0.00 to 0.20 m is 0.64 cmolcdm
-3

, while the 

depth is 0.43 m 0.20-0.40 cmolcdm
-3

 (Table 4), and these 
levels considered low by Ribeiro et al. (1999). However, 
replacement of Ca

2+
 is less than the amount extracted at 

doses of 500 and 1.000 m³ ha
-1

 SW, however, higher in 

doses of 2000 and 2500 m³ ha
-1

 SW (Figure 3d), not 
favoring the accumulation of calcium in two depths 
assessed (Table 4). Queiroz et al. (2004) observed no 
changes in Ca

2+
 levels in soil with wastewater.  

The base saturation (V) showed a significant increase 
in the depth of 0.20-0.40 m (35.09%) with the application 
of SW doses (Table 4) in relation to the initial content 
(30%) (Table 1). This result is related to the increase in 
potassium and magnesium content at this depth. With the 
application of SW, the levels of organic matter that were 
2.3% at a depth of 0.00 to 0.20 and 1.6% in the depth  
0.20-0.40 m (Table 1), did not show any increase due to 
the application of the treatments (Table 4), with no 
significant differences. Mattias (2006) did not observe an 
increase of organic matter in the application of liquid 
effluent from swine farms.  

The lack of response to the increase of organic matter 
can be explained by Assmann et al. (2006) who observed 
no increase in organic matter content by applying liquid 
swine waste. For, according to the authors, they must be 
considered inherent characteristics of manure used, 
where the quality of the organic compounds may 
determine a greater or lesser accumulation in the soil. 
The organic compounds present in the liquid manure of 
pigs have been easily digested by oxidizing in a few days 
or weeks and are favored for higher microbial activity. 
The microbial biomass is considered a vital part of the 
organic matter, composed of micro-organisms (bacteria, 
fungi and actinomycetes), comprising 2 to 5% carbon and 
up to 5% of total nitrogen (Moreira and Siqueira, 2003). 
There were no significant differences among treatments 

in nutrient contents Fe, Cu
2+

 and Zn 
2+

 (Table 4). 

However, for Lucas et al. (2013) and Rosa et al. (2017a, 
b), the applications of swine wastewater favored the 
accumulation of copper and zinc.  

According  to Girotto (2007), successive applications of 

 
 
 

SW to the soil cause accumulation of Zn
2+

 in the surface 
layers that were found significant for the accumulation of 

Zn
2+

 layer to the depth of 0.10 m. The Cu
2
 + and Zn

2+
  

elements are used in animal feed as a supplement, 
without being fully absorbed and therefore excreted in 
high amounts, remaining in SW (Rosa et al., 2017b). The 
high capacity of Oxisol adsorbs Cu and Zn and low 
mobility of these elements could be verified by (Lopes et 
al., 2014). Gomes Filho et al. (2001) reported poor 
copper mobility in soil, stating that this element among 
the heavy metals is the most strongly adsorbed or 
complexed by the soil. Furthermore, according to Lopes 

et al. (2014) high adsorption of Cu
2+

 and Zn
2+

 may be the 

result of an increase in soluble organic compounds, 
which have the ability to complex these nutrients. The 
average leaf content of nutrients N, P, K, S and Zn 
differed due to the application of increasing doses of SW 
(Table 5). Thus, the application of different doses of SW 
influenced the foliar contents of these nutrients.  

Knowledge of the leaf content of an intensive system of 
production, mainly in a very demanding nutritionally 
species, such as Tifton 85 grass, is very important for 
determining the amount of nutrient to be restored, 
reaching thus the mass production desired dry matter. 
Silva (1999) described the range of suitable 
concentrations for Tifton as follows, relative to 
macronutrients: C = 20.0-26.0; P = 1.5-3.0; K = 15.0-30.0; 

Ca = 3.0-8.0; Mg = 1.5-4.0; S = 1.5-3.0 g kg
-1

. For 
optimal range micronutrient is: B = 5.0-30.0; Cu = 4.0-
20.0; Fe = 50.0-200.0; Mn = Zn = 20.0-300.0 and 15.0-

70.0 mg kg
-1

.  
In this experiment the nutrient contents fall within the 

proper range suggested by Silva (1999), except Zn, 

wherein the average of treatments was 144 mg kg
-1

. The 
extraction of nutrients by dry weight of the shoot (above 
10 cm) was high, demonstrating that the Tifton 85 grass 
has high nutrient extraction capacity (Table 6). The 
extraction of macro and micronutrients of shoots of grass 
Tifton 85 follows the following order: N> K> Ca> P> Mg> 
S> Mn> Fe> Zn> B> Cu (Table 6). As the DM output 
followed a linear growth projection (Figure 2a), all 
nutrients obtained the same trend (Figures 3 and 4).  

The dose of 500 m³ SW ha
-1

 provided the soil 411.08 

kg ha
-1

 of N and extraction was 358.01 kg ha
-1

 of N, 
which corresponds to 87.09% of the applied level. These 
results show that the synchronism between the 
availability of N from SW culture and demand generated 



9 

 

  
 
 

 
Table 6. Extraction of nutrients from the Tifton 85 grass (dry matter), subjected to increasing doses of SW.  
 
 Element N P K S Ca Mg B Cu Fe Mn Zn 

  .....................................................................................   kg ha
-1

........................................................................     

 Averages 405.14 57.77 387.69 31.48 77.05 49.68 0.33 0.2 2.88 4.61 2.86 

 p-valor 0.001 0.001 0.000 0.005 0.017 0.008 0.057 0.025 0.007 0.078 0.050 

 C.V. % 7.73 6.25 5.34 11.23 9.65 8.98 10.50 13.30 8.49 27.09 15.36  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
Figure 4. Extraction of micronutrients Cu (a), Fe (b), Mn (c) and Zn (d) by dry weight.  
** Significant 10% probability. The dotted line refers to the addition of nutrients to the soil by increasing doses of SW and the 
continuous line for extracting the forage. 

 
 

 

a beneficial effect on the nutrient recycling process. This 
balance can reduce the mineral N concentration in the 
soil solution, promoting the sustainability of the 
production system. Surely, this dose is the most 
appropriate in the environmental point of view with 
respect to N (Figure 3a). Sharpe and Harper (2002) 
further justify about 35% of N SW is lost in the form of 

NH3 during application. The phosphorus provided by 

increasing doses of SW was lower than that extracted by 
the plant in all treatments (Figure 3b), since the nutrient 

content in this SW is low (20.46 mg L
-1

). Silva et al. 

 
 
 

 

(2012) conducted an experiment on the Bonsucesso farm 
and found that the phosphorus content in SW was 
reduced by approximately 80% to pass the Biodigester 
and the lagoon decantation, thus justifying the low 
content in SW. According to Mattias (2006), the 
accumulation of P in soils treated with SW correlates with 
a lower N/P ratio of waste, since it meet the required 
amounts of N by plants it is necessary to simultaneously 
apply greater amounts of P resulting in accumulation and 
organic P moving in the environment. At a dose of 500 m³ 

ha
-1

 potassium applied via wastewater (254.69 kg ha
-1

) 



10 

 

 
 
 

 

was lower than that extracted by the plant (Figure 3c). 
Higher doses left nutrient residues in the soil (Figure 3c 
and Table 4).  

The calcium extractions (Figure 3d) and magnesium 
(Figure 3e) by Tifton 85 grass were lower than the 

amount provided by the SW dose 2.000 m³ ha
-1

. In this 

dose, the SW has provided the soil 103.8 kg ha
-1

 of 

calcium and magnesium 67.06 kg ha
-1

 and extracting the 

Tifton 85 was 86.16 kg ha
- 1

 of calcium and 55.92 kg ha
-1

 
magnesium, this being the SW dose sufficient to provide 
the amount extracted at 85 Tifton. There is a tendency to 
accumulate copper (Cu) in soil with SW (Figure 4a). Cu 
average extraction obtained in the dry matter of grass 

Tifton 85 was 0.2 kg ha
-1

. The lowest dose of SW added 
tem times more than the Cu extracted by forage, while 
the highest dose added 40 more times. Figure 4 
illustrates the low extraction by Cu Tifton 85 grass.  

Lima and Miyada (2003) conducted an experiment with 
Cu in the form of cupric citrate, a more soluble source 
with greater utilization by the animal and less waste left in 
the excretions. Thus, they concluded that cupric citrate 
may replace the Cu sulfate, contributing to reducing this 
nutrient in the SW. SW in any of the doses could supply 
the manganese (Mn) needed for the production of Tifton 
85 grass (Figure 4c). It is necessary to monitor this 
nutrient in the soil and the plant, as part of nutrients 
extracted by grass after being consumed by cattle and 
returned to the soil through animal waste. Zn supplied by 

the dose of 500 m³ ha
-1

 was 2.86 kg ha
- 1

 approaches the 

extracted amount of and 2.72 kg ha
-1

 at Tifton 85 (Figure 

4d). The view on organic waste recycling needs to be 
diversified, being recovery and recycling of nutrients from 
organic wastes are a possible solution. When organic 
waste recycling is complemented by nutrient extraction, 
some nutrient loops within society can be closes, 
enabling more sustainable agricultural production in 
future (Kirchmann et al., 2017). 
 

 

Conclusions 

 

The application of increasing doses of SW promoted a 
linear increase in carrying capacity, mass production of 
dry matter, density, height, and mass accumulation rate 
of dry matter per day of Tifton 85 grass. The wastewater 
doses promoted changes in soil chemical properties. The 

dose of 2.000 m³ ha
-1

 supplied the nutritional needs of 
the grass Tifton 85 in nitrogen, potassium, calcium, 
magnesium, copper, iron and zinc. 
 

 

ACKNOWLEGEMENTS 

 

Authors thank the Federal University of Viçosa (UFV), 
Federal University of Uberlândia (UFU) and the 
Foundation for the State of Minas Gerais Research 
(FAPEMIG) for supporting research in the state of 

 
 
 
 

 

Minas Gerais. 

 

CONFLICT OF INTERESTS 
 
The author has not declared any conflict of interests. 

 
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