**5. Comparison between the floristic-holistic method and the pastoral value method**

To analyze how much the data obtained with the FHM deviate from the data obtained with the PVM [2, 3], five field transects were carried out with each method. To avoid census errors, both methods were performed on each transect line at the same time and they were recorded on separate forms (**Figure 6**). The surveys were carried out in 2015, in a mount area that bio-climatically corresponds to the warm semidesert in Ref. [5] (**Figure 1**: Green Point). They were carried out in the "El Moro" livestock establishment, Telsen Department, Province of Chubut, and 120 km north of *The Floristic-Holistic Method for Arid, Semiarid, and Subhumid Areas: A Tool… DOI: http://dx.doi.org/10.5772/intechopen.106226*

**Figure 6.** *Field survey. Observe the data collection with two spreadsheets at the same time (each spreadsheet corresponds to each one of the methods).*

the city of Trelew and is accessed by provincial route N°. 8 (**Figure 1**. Green point). The area is between 30 and 50 meters above sea level and is characterized by having average rainfall that averages 150 mm per year. Winds prevail from the west sector, sometimes reaching speeds greater than 80 km per hour. The average annual temperature is 13–14°C [17].

The "El Moro" establishment is located in the biogeographical province of Austral Mount. It is characterized by the constant presence of the "Jarillas," shrubs belonging to the Zigofiláceas family. The Zygophyllaceae species with the greatest representation in the study area are the "Jarilla" *Larrea divaricata* and the "Jarilla fine" *Larrea nitida,* as well as the "Jarilla creeping" *Larrea ameghinoi.* These plants reach one or two meters in height, or less (in very windswept areas), and grow scattered, leaving clearings where herbs develop at the right times. Among the shrubs that grow associated with Jarillas, the "Alpataco" *Prosopis alpataco*, the "Mata sebo" *Monttea aphylla*, the "Monte negro" *Bougainvillea spinosa*, the "Pichana" *Senna aphylla*, and the "Chirriadora" *Chuquiraga erinacea ssp hystrix,* among others. Other important components of the Austral Mount are they are the representatives of the family Cactaceae, the grasses, and other herbaceous plants.

According to the censuses carried out, both methods showed the same values of bare soil (average 43.8%), plant cover (26.6%), dead plant material (standing dead) 21.2%, and litter 8.4%. Analyzing the biological forms, it was observed that herbs were found between 3.5 and 4.2%, grasses between 16 and 18.5%, respectively, shrubs between 73 and 76.8%, and cacti between 13.5 and 4.5% (**Table 2**). Regarding the comparison of both methods, it can be observed that the differences are slight, but a


#### **Table 5.**

*Comparison of biological forms in both methods.*

tendency to overestimate grasses (difference of 2.49%) and underestimate shrubs (difference of 3.72%) is observed in the PVM (see **Table 5**).

Analyzing forms and biological types together, a slight difference was observed between both methods (**Table 1**). For all forms, it was observed that the percentage was less than 0.5% between both methods, except in perennial grasses, where the percentage was 1.61% higher in PVM, and in shrubs, which was 3.87% lower in PVM (see **Table 6**).

On the other hand, the status showed that native species ranged between 51.3 and 55.3%, endemic species between 35.7 and 38.6%, and introduced species between 8.9 and 10%. Comparing both methods, a difference between 1 and 4% was observed between both methods (see **Table 7**). Recording the greatest differences between native species is probably due to the fact that in this category "native species" has the highest number of registered species compared with "endemic species" and "introduced species."


#### **Table 6.**

*Comparison of forms and biological types in both methods.*


#### **Table 7.**

*Comparison of the status of both methods.*

*The Floristic-Holistic Method for Arid, Semiarid, and Subhumid Areas: A Tool… DOI: http://dx.doi.org/10.5772/intechopen.106226*


#### **Table 8.**

*Comparison of taxonomic type in both methods.*

Analyzing the taxonomic type, it was observed that eudicots range between 81.3 and 83.8%, and monocots between 16.1 and 18.6% (see **Table 8**). Comparing both methods, it is observed that the PVM would be overestimating monocots by 2.5% and underestimating eudicots by 2.5%. It is precisely the same trend that has been observed above, a slight tendency to underestimate shrubs (eudicots) and overestimate grasses (monocotyledons).

Nineteen botanical families were registered. For the taxonomic identification of the plants, the names of the families accepted in the catalog of vascular plants of the southern cone [7] were used. The traditional designations for the names of the families: Compositae, Cruciferae, Gramineae, Leguminosae, and Umbelliferae have been replaced by those accepted in more recent publications [18] as Asteraceae, Brassicaceae, Poaceae, Fabaceae, and Apiaceae, respectively.

The analysis of the botanical families showed that there is a dominance of 5–6 families (Zygophyllaceae, Poaceae, Solanaceae, Verbenaceae, Fabaceae, Amaranthaceae) over the rest of the families, but that dominance is different if it is analyzed by a method or on the other (See **Table 9**).

The MFH analysis showed a dominance of the families Zygophyllaceae and Solanaceae (both with 18.79%). Then, Poaceae (16.03%), Fabaceae (13.93%), Verbenaceae (12.22%), Chenopodiaceae (8.41%), Cactaceae (3.55%), Asteraceae (2.5%), and Geraniaceae (1.45%) and the rest of the families represented in less than 1%. The MVP analysis showed a dominance of the Poaceae family (18.52%), along with Solanaceae (16.48%), Verbenaceae and Zygophyllaceae (both 14.44%), Fabaceae (13.65), Chenopodiaceae (8.95%), Cactaceae (4.08%), Asteraceae (2.67%), Geraniaceae (1.57%), Anacardiaceae (1, 26), and the rest of the families represented in less than 1%.

On the other hand, comparing both methods, it was observed that most of the botanical families they show a difference of less than 0.5%. But comparing the values of the differences, it was recorded that this difference is 2.2–2.4% higher in the families Poaceae and Verbenaceae for the MVP and 2.3% lower in Solanaceae, and 4.35% lower in Zygophyllaceae for the MVP (**Table 8**). These differences may be due to the fact that in the census of the PVM the presence of Zygophyllaceae would be underestimated due to the fact that the number of touches is not counted, but rather it is only registered with an "X" as a non-forage. Regarding the Solanaceae family, it could be slightly underestimated with the PVM because the needle touched nonforage portions of it. And finally, again a slight tendency to overestimate grasses (Poaceae) and some species of Verbenaceae is observed.

The diversity index (Shanon-Weaver) was similar in both methods (FHM 1.05, and PVM 0.99), showing a percentage difference of 0.06. Plant density showed different values in both methods. The FHM calculation resulted in 3420 plants/ha, and the MVP showed 3100 plants/ha. The difference of both methods is 320 plants/ha. This difference is quite significant and may be due to the number of touches each plant has.


#### **Table 9.**

*Comparison of botanical families in both methods.*

It is worth mentioning that in the VPM 637 total touches were recorded (direct forage touches + indirect forage touches + the touches corresponding to the direct and indirect "Xs"). On the other hand, in the MFH, 761 total touches were recorded (direct touches + indirect touches).

The analysis of forage availability and pastoral value, by the MVP, revealed the following data: The pastoral value ranged between 3.3 and 11.72 (average 5.78), and the average forage availability of 76.85 Kg dry matter/hectare. Showing a usable forage availability (with a use factor of 30%) of 23.06 Kg dry matter/hectare, this value would be giving a stocking rate of 0.08 OLU/ha or 0.04 EPS/ha. This would be equivalent to 200 capons per league or 400 sheep per league.

On the other hand, the MFH showed a pastoral value that ranged between 3.7 and 15.3 (average 9.27), and the average forage availability was 140.69 Kg dry matter/hectare. The usable forage availability (with a use factor of 30%) of 42.21 Kg dry matter/hectare. This last value would give a stocking rate of 0.14 OLU or 0.08 EPS/ha.

Comparing both methods, an important difference between the methods is observed (see **Table 9**). The pastoral value calculated by the FHM shows a value higher than that calculated by the PVM (37.6% higher), and the estimate of forage availability and stocking rate shows a value 45.3% higher than that calculated by the *The Floristic-Holistic Method for Arid, Semiarid, and Subhumid Areas: A Tool… DOI: http://dx.doi.org/10.5772/intechopen.106226*


**Table 10.**

*Comparison of pastoral value, forage availability, and stocking rate for both methods.*

PVM (see **Table 10**). These differences will lie in the way of recording the data by both methods. In the FHM, all touches are recorded, while in the PVM, all forage touches are recorded but not all non-forage touches.

In nature, domestic grazers coexist with the natives and they all have different ways of feeding, some cut, others browse, uproot, rough, etc., and they also select what they most want and consume at different heights. Anyone would assume that the larger the animal, it could graze at higher altitudes, but this is not always the case in nature, there are many medium-sized and small-sized grazers and/or browsers that graze at high altitudes, as can be seen in small- and medium-sized rodents (guinea pigs, tuco-tucos, mice, hares, rabbits, and maras), and various species of birds, lizards, etc., which can be seen at the top of the bushes consuming flowers, fruits, and leaves (**Figures 7**–**11**), but also in the very intricate interior of the bushes, both sites are inaccessible to domestic livestock, but are inaccessible to many species of wildlife.

On the other hand, branches and thorns of shrubs were observed, non-forage parts by MVP, heavily browsed, debarked, and in some cases cut (**Figure 10**) by rodents. It is worth mentioning that the cutting of rodent branches is recognized because it is always a bevel cut. The most heavily barked shrubs were those of *Bougainvillea, Condalia, Lycium, Prosopis, Prosopidastrum,* and *Schinus species.* Despite long hours of observation and on numerous occasions, we were unable to determine whether this bark is consumed by rodents or they only perform this action to wear down and sharpen their teeth. But it is important to note that this action of debarking branches occurs more intensely in times of great drought and when there is not much forage supply and living flora. It is worth mentioning that in MVP, the person in charge of carrying out the sampling is the one who decides if the plant and/or part of the plant is edible or not, and if it is accessible or not for livestock. Therefore, in the FHM, by surveying everything that is alive, regardless of whether it is forage or not, this bias is avoided. The diversity of plant species in the arid and semiarid zones of Patagonia is crucial to cushion the effects of drought on the functioning of ecosystems [19]. Among the most important conclusions, they observed that ecosystems with a greater diversity of plant species are more likely to have species that are more tolerant to drought and, in addition, can make more efficient use of available resources due to the complementarity and synergistic interactions between the species.

**Figure 7.** *Detail of debarked branches at the base of the* Prosopidastrum striatum *trunks.*
