**4. Water-use efficiency and plant responses**

The water content in the soil profile is one of the main factors of growth and productive vigor of coffee, mainly because it is predominantly implanted in a dry land system. In this sense, the knowledge of soil water dynamics in the root zone in production areas is strategic because it predicts the success of agricultural activity. Management strategies can contribute to the efficient use of stored soil water from rainfall and enable positive responses to the crop.

In order to reduce the effects of water deficit, a plastic film (double-sided, black and white) was used as mulching covering the coffee growing line. Such management provided greater soil water storage up to 0.60 m in an Argisol (Ultisol), with soil moisture above 30% in the dry season, from May to September (**Figure 10**). In the topsoil, the soil moisture also remained higher, especially in warmer seasons, such as in January. These results coincide with the highest growth in stem height and diameter over the first year of coffee development [51, 52], showing that mulching may be an important alternative for keeping water in the root zone at the most critical time for crop development.

In a Cerrado Latosol cultivated with coffee under a conservation system [10], soil moisture was monitored daily during 2010 by means of a capacitance multi-sensor probe to a depth of 1.0 m [53, 54]. Throughout the evaluated period, the lowest moisture values were observed in the 0.50 to 0.75 m layer, indicating that the coffee tree extracted the largest amount of water at this depth (**Figure 11**), coinciding with significant presence of coffee roots [7] (**Figure 4**). In addition, in the months corresponding to the dry season in the region (June to August), it was observed low humidity values in the depth of 1.00 m, and thus deep water absorption, which may have contributed to reduce the water stress suffered by the plant. In this sense, the groove opening and limestone incorporation at 0.60 m associated with the application of additional gypsum may be important for the attenuation of water deficit.

An alternative for soil moisture monitoring is the use of remote sensors, given their repeatability characteristics, access to large areas and easy handling. However, it should be taken into account that coffee is a perennial crop with high root system activity at depth, and the use of remote sensor data to directly measure soil moisture is limited to a few centimeters below the surface (±5 cm) [55], not covering the entire area of water extraction by the roots [56]. Santos et al. [57] used the vegetation index EVI-2 to monitor the vegetative vigor of the coffee tree and to correlate it

**35**

**Figure 11.**

*from Silva [53].*

**Figure 10.**

*Barbosa [51].*

*Soil Management and Water-Use Efficiency in Brazilian Coffee Crops*

with moisture data at different depths. The authors concluded that it is possible to estimate the water content in the root zone using EVI-2, and that the humidity at a depth of 0.60 m is the one that most reflects the water situation of the plant.

*. Source: Adapted* 

*Continuous variation of soil moisture (% by volume) in the planting line (sensor positioned 0.15 m from the coffee tree trunk) as a function of depth (0–1.00 m) and time (March/2010 to December/2010) in a very clayey gibbsitic-oxidic dystrophic red Latosol with coffee during the 2nd year under management system described in Serafim et al. [10], which includes deep preparation with chemical correction up to 0.60 m, cultivation of* 

*Brachiaria between the rows and application of additional gypsum at a dose of 28 Mg ha<sup>−</sup><sup>1</sup>*

*Continuous variation of soil moisture in 2014 in the 0–0.60 m layer of Argisol as a function of conventional management (TES) and plastic cover (MM) in the first year of coffee cultivation. Source: Adapted from* 

*DOI: http://dx.doi.org/10.5772/intechopen.89558*

### *Soil Management and Water-Use Efficiency in Brazilian Coffee Crops DOI: http://dx.doi.org/10.5772/intechopen.89558*

#### **Figure 10.**

*Coffee - Production and Research*

aimed at maximizing production [50].

**4. Water-use efficiency and plant responses**

rainfall and enable positive responses to the crop.

most critical time for crop development.

[2, 43, 46, 49] However, because it was submitted to the conservationist management system, there was a small increase in the intermediate pores when compared to the greater depth evaluated in both soils, especially the one with gibbsite.

water unavailable to the roots of coffee trees [48, 49] (**Figure 9**).

There is higher water retention in the cryptopores of gibbsitic Acrustox (pores with diameter < 0.01 μm) due to the high energy (3500 kPa), which makes this

The authors mentioned in the previous paragraph point out that deep preparation and maintenance of Brachiaria sp. should be considered as the main factors of

the supporting factor in the structure of the soils. Carducci et al. [6], when evaluating the same soils in 3D images obtained by X-ray computed tomography, verified that kaolinitic Latosols presented high spatial variability of the soil structure. These pores resulted from the rapid and well-branched growth of the coffee root system [7, 8]. This is extremely relevant information given that the interactions between soil and root have been considered as a key element for the second green revolution

The water content in the soil profile is one of the main factors of growth and productive vigor of coffee, mainly because it is predominantly implanted in a dry land system. In this sense, the knowledge of soil water dynamics in the root zone in production areas is strategic because it predicts the success of agricultural activity. Management strategies can contribute to the efficient use of stored soil water from

In order to reduce the effects of water deficit, a plastic film (double-sided, black and white) was used as mulching covering the coffee growing line. Such management provided greater soil water storage up to 0.60 m in an Argisol (Ultisol), with soil moisture above 30% in the dry season, from May to September (**Figure 10**). In the topsoil, the soil moisture also remained higher, especially in warmer seasons, such as in January. These results coincide with the highest growth in stem height and diameter over the first year of coffee development [51, 52], showing that mulching may be an important alternative for keeping water in the root zone at the

In a Cerrado Latosol cultivated with coffee under a conservation system [10], soil moisture was monitored daily during 2010 by means of a capacitance multi-sensor probe to a depth of 1.0 m [53, 54]. Throughout the evaluated period, the lowest moisture values were observed in the 0.50 to 0.75 m layer, indicating that the coffee tree extracted the largest amount of water at this depth (**Figure 11**), coinciding with significant presence of coffee roots [7] (**Figure 4**). In addition, in the months corresponding to the dry season in the region (June to August), it was observed low humidity values in the depth of 1.00 m, and thus deep water absorption, which may have contributed to reduce the water stress suffered by the plant. In this sense, the groove opening and limestone incorporation at 0.60 m associated with the application of additional gypsum may be important for the attenuation of water deficit. An alternative for soil moisture monitoring is the use of remote sensors, given their repeatability characteristics, access to large areas and easy handling. However, it should be taken into account that coffee is a perennial crop with high root system activity at depth, and the use of remote sensor data to directly measure soil moisture is limited to a few centimeters below the surface (±5 cm) [55], not covering the entire area of water extraction by the roots [56]. Santos et al. [57] used the vegetation index EVI-2 to monitor the vegetative vigor of the coffee tree and to correlate it

), act as

this management system. The additional surface applied gypsum (7 kg m<sup>−</sup><sup>1</sup>

**34**

*Continuous variation of soil moisture in 2014 in the 0–0.60 m layer of Argisol as a function of conventional management (TES) and plastic cover (MM) in the first year of coffee cultivation. Source: Adapted from Barbosa [51].*

#### **Figure 11.**

*Continuous variation of soil moisture (% by volume) in the planting line (sensor positioned 0.15 m from the coffee tree trunk) as a function of depth (0–1.00 m) and time (March/2010 to December/2010) in a very clayey gibbsitic-oxidic dystrophic red Latosol with coffee during the 2nd year under management system described in Serafim et al. [10], which includes deep preparation with chemical correction up to 0.60 m, cultivation of Brachiaria between the rows and application of additional gypsum at a dose of 28 Mg ha<sup>−</sup><sup>1</sup> . Source: Adapted from Silva [53].*

with moisture data at different depths. The authors concluded that it is possible to estimate the water content in the root zone using EVI-2, and that the humidity at a depth of 0.60 m is the one that most reflects the water situation of the plant.

#### **Figure 12.**

*Water use in layers up to 1.00 m depth during the dry season (May 2010) and in the summer (November 2010) for coffee trees installed in October/2008 due to management with deep soil preparation and limestone incorporation at 0.60 m depth, differing by presenting Brachiaria between the rows and additional application of 7 Mg ha<sup>−</sup><sup>1</sup> of gypsum (G-7) or 28 Mg ha<sup>−</sup><sup>1</sup> of gypsum (G-28), and without application of additional gypsum and uncovered line (CV-0). Source: Ivan Célio Andrade Ribeiro.*

To detail the use of additional gypsum practice, water use by the coffee tree in the soil profile was estimated at different time intervals in 2010 (**Figure 12**). The coffee tree consumed water to a depth of 0.60 m in both evaluations performed and for all managements, which corroborates the lower moisture values in this layer (**Figure 11**), confirming the importance of deep tillage and soil correction at 0.60 m. The highest water consumption was observed for treatment G-7, followed by G-28 and lastly for CV-0. The use of additional gypsum allowed the development of thin roots in treatments G-7 and G-28 when compared with CV-0 [11], which may be due to the high levels of exchangeable Ca2+, Mg2+ and K+ in the soil solution, which remained at adequate values to a depth of 0.85 m in the management with additional gypsum application [58].

Water use at a depth of 1.0 m was observed only in the G-7 treatment in November 2010, where the plant consumed about 6% of the stored water. At that time, the coffee tree was 2 years old, showing potential for deep water extraction. Moreover, even in the rainy season there was drought of more than 20 days [29, 53], associated with lower rainfall in the region this year compared to the historical average [59], implying less soil water storage. However, the high soil moisture at a depth of 1.00 m - above the critical moisture content for reducing maximum coffee perspiration in all managements [29] - indicates that this layer is an important water reservoir that can be accessed by plants during the driest or summer periods, reinforcing the importance of deepening the root system through management [29, 59].

**37**

**Figure 13.**

*or 28 Mg ha<sup>−</sup><sup>1</sup>*

*Source: From authors.*

*Soil Management and Water-Use Efficiency in Brazilian Coffee Crops*

Although management with additional gypsum (G-7 and G-28) provided higher water consumption compared to CV-0, it was not possible to differentiate its effects on water stress suffered by plants, evaluated by leaf water potential (ψf) in January, April, and August 2010 (**Figure 13**). It is noteworthy that in CV-0, although no additional gypsum was applied, liming was performed on the surface and in the planting furrow to a depth of 0.60 m, which favored the deepening of the root

The highest water stress was observed in August (**Figure 13**), coinciding with the peak of the dry season in the region and the lowest soil water content [29, 59]. However, all observed ψf values were below the critical range of water stress that leads to a reduction in coffee crop production, which is between −1.8 and −2.5 MPa

Regarding plant growth, lower plant height values were observed in the G-7 and G-28 managements when compared with CV-0 (**Figure 13**), which may be explained by competition for root-shoot photoassimilates [63], since the coffee tree showed denser and deeper root systems for G-7 and G-28 [11]. In addition, the evaluations were carried out shortly after planting and, considering that the main morphological and physiological characteristics of the coffee root system complete its development at 5 years of age [1], it is expected that the investments made in liming, application additional gypsum and fertilization result in greater root develop-

Despite the lower initial plant growth, the adoption of the conservation management system provided maintenance of the water state of plants during the dry and summer season (**Figure 13**), resulting in statistically equal yields between CV-0, G-7 and G-28 management system at the first harvest in 2011 [29], highlighting the importance of deep tillage and soil correction. However, in 2012, higher yields were obtained in the managements G-7 and G-28. On average, production was 52.8 bags

 in G-28 [59]. Coffee plants take 2 years to complete their phenological cycle [64]. Thus, soil moisture in 2010 influenced production in 2011 and 2012, demonstrating the positive effect of investments in additional gypsum associated with the

*Water stress assessed by leaf water potential (Ψf) at three times of the year (January 5; January 18 and August 20, 2010), and plant growth at height assessed continuously each month (January 5, 2010 to June 18, 2011) for coffee planted in October 2008 due to management with deep soil preparation and limestone incorporation,* 

 *of gypsum (G-28), without application of additional gypsum and uncovered gypsum (CV-0).* 

*differing for presenting Brachiaria between the rows and additional application of 7 Mg ha<sup>−</sup><sup>1</sup>*

in G-7 and 58.0 bags

 *of gypsum (G-7)* 

ment in the G-7 and G-28 managements in subsequent years [21].

in CV-0 (1 bag = 60 kg of coffee grains), 54.5 bags ha<sup>−</sup><sup>1</sup>

*DOI: http://dx.doi.org/10.5772/intechopen.89558*

system [7].

[60–62].

ha<sup>−</sup><sup>1</sup>

ha<sup>−</sup><sup>1</sup>

*Coffee - Production and Research*

To detail the use of additional gypsum practice, water use by the coffee tree in the soil profile was estimated at different time intervals in 2010 (**Figure 12**). The coffee tree consumed water to a depth of 0.60 m in both evaluations performed and for all managements, which corroborates the lower moisture values in this layer (**Figure 11**), confirming the importance of deep tillage and soil correction at 0.60 m. The highest water consumption was observed for treatment G-7, followed by G-28 and lastly for CV-0. The use of additional gypsum allowed the development of thin roots in treatments G-7 and G-28 when compared with CV-0 [11], which may be due to the high levels of

*Water use in layers up to 1.00 m depth during the dry season (May 2010) and in the summer (November 2010) for coffee trees installed in October/2008 due to management with deep soil preparation and limestone incorporation at 0.60 m depth, differing by presenting Brachiaria between the rows and additional application* 

to a depth of 0.85 m in the management with additional gypsum application [58].

of deepening the root system through management [29, 59].

Water use at a depth of 1.0 m was observed only in the G-7 treatment in November 2010, where the plant consumed about 6% of the stored water. At that time, the coffee tree was 2 years old, showing potential for deep water extraction. Moreover, even in the rainy season there was drought of more than 20 days [29, 53], associated with lower rainfall in the region this year compared to the historical average [59], implying less soil water storage. However, the high soil moisture at a depth of 1.00 m - above the critical moisture content for reducing maximum coffee perspiration in all managements [29] - indicates that this layer is an important water reservoir that can be accessed by plants during the driest or summer periods, reinforcing the importance

in the soil solution, which remained at adequate values

 *of gypsum (G-28), and without application of additional gypsum* 

**36**

**Figure 12.**

*of 7 Mg ha<sup>−</sup><sup>1</sup>*

exchangeable Ca2+, Mg2+ and K+

 *of gypsum (G-7) or 28 Mg ha<sup>−</sup><sup>1</sup>*

*and uncovered line (CV-0). Source: Ivan Célio Andrade Ribeiro.*

Although management with additional gypsum (G-7 and G-28) provided higher water consumption compared to CV-0, it was not possible to differentiate its effects on water stress suffered by plants, evaluated by leaf water potential (ψf) in January, April, and August 2010 (**Figure 13**). It is noteworthy that in CV-0, although no additional gypsum was applied, liming was performed on the surface and in the planting furrow to a depth of 0.60 m, which favored the deepening of the root system [7].

The highest water stress was observed in August (**Figure 13**), coinciding with the peak of the dry season in the region and the lowest soil water content [29, 59]. However, all observed ψf values were below the critical range of water stress that leads to a reduction in coffee crop production, which is between −1.8 and −2.5 MPa [60–62].

Regarding plant growth, lower plant height values were observed in the G-7 and G-28 managements when compared with CV-0 (**Figure 13**), which may be explained by competition for root-shoot photoassimilates [63], since the coffee tree showed denser and deeper root systems for G-7 and G-28 [11]. In addition, the evaluations were carried out shortly after planting and, considering that the main morphological and physiological characteristics of the coffee root system complete its development at 5 years of age [1], it is expected that the investments made in liming, application additional gypsum and fertilization result in greater root development in the G-7 and G-28 managements in subsequent years [21].

Despite the lower initial plant growth, the adoption of the conservation management system provided maintenance of the water state of plants during the dry and summer season (**Figure 13**), resulting in statistically equal yields between CV-0, G-7 and G-28 management system at the first harvest in 2011 [29], highlighting the importance of deep tillage and soil correction. However, in 2012, higher yields were obtained in the managements G-7 and G-28. On average, production was 52.8 bags ha<sup>−</sup><sup>1</sup> in CV-0 (1 bag = 60 kg of coffee grains), 54.5 bags ha<sup>−</sup><sup>1</sup> in G-7 and 58.0 bags ha<sup>−</sup><sup>1</sup> in G-28 [59]. Coffee plants take 2 years to complete their phenological cycle [64]. Thus, soil moisture in 2010 influenced production in 2011 and 2012, demonstrating the positive effect of investments in additional gypsum associated with the

#### **Figure 13.**

*Water stress assessed by leaf water potential (Ψf) at three times of the year (January 5; January 18 and August 20, 2010), and plant growth at height assessed continuously each month (January 5, 2010 to June 18, 2011) for coffee planted in October 2008 due to management with deep soil preparation and limestone incorporation, differing for presenting Brachiaria between the rows and additional application of 7 Mg ha<sup>−</sup><sup>1</sup> of gypsum (G-7) or 28 Mg ha<sup>−</sup><sup>1</sup> of gypsum (G-28), without application of additional gypsum and uncovered gypsum (CV-0). Source: From authors.*

maintenance of Brachiaria in the G-7 and G-28 treatments, which provided higher water consumption by the plant in 2010 (**Figure 12**).

The trend of higher production for management with additional gypsum was confirmed in the 2013 crop, in which 63.0 bags ha<sup>−</sup><sup>1</sup> was produced in CV-0; 75.5 bags ha<sup>−</sup><sup>1</sup> in G-7, and 71.1 bags ha<sup>−</sup><sup>1</sup> in G-28 (data obtained through personal communication with consultants in the area). However, in the 2014 harvest, only the G-28 treatment presented higher yield (87.2 bags ha<sup>−</sup><sup>1</sup> ) when compared with CV-0 (85.6 bags ha<sup>−</sup><sup>1</sup> ). Management G-7 presented the lowest yield (57.5 bags ha<sup>−</sup><sup>1</sup> ). However, when evaluating the general average of the first four seasons, it is observed that there is little difference between the evaluated managements, in which in CV-0 were harvested 63.6 bags ha<sup>−</sup><sup>1</sup> , 60.5 bags ha<sup>−</sup><sup>1</sup> in G-7 and 68.6 bags ha<sup>−</sup><sup>1</sup> in G-28.
