**3. Materials and methods**

Floristic surveys were carried out with various methods along different sectors of Argentina's Arid Diagonal, perfecting this method from 1344 transects, with 260,000 base data that will later be expanded to other derived data and a sampling effort of 403,200 steps (403.2 kilometers) surveyed. This distance was covered on foot, lowering a rod every three steps to take a census of all the flora present. The set of transects represents the environmental evaluation of the flora of the regions over two decades, integrating 21 years of sampling (between 2001 and 2022).

Considering the geographical distribution of the transects, 181 correspond to transects carried out in the province of Santa Cruz, 780 in Chubut, 23 in Río Negro, and 360 in Mendoza. Taking into account the geographical positions of each transect, results from census areas belonging to the high Andean, puna, payunia, patagonia, cardonal, and mount regions were included for the evaluation of the method [5]. Specifically for the bioclimatic zones raised within the South American Arid Diagonal

#### **Figure 1.**

*Distribution of rainfall and physiognomies in the area of the South American Arid Diagonal. Taken from [5]. In red, areas where flora censuses were carried out with the proposed method. The green dot indicates a simultaneous census area with the Floristic-Holistic Method (FHM) and the Pastoral Value Method (PVM).*

[5], 555 transects belonging to the cold Mediterranean steppe, 545 to warm semideserts, and 158 to the Andean range are recognized (**Figure 1** and **Table 1**). Considering hot and cold environments of the total number of transects, 545 correspond to hot desert transects and 713 to cold deserts.

It is worth mentioning that the method was applied in different ecological areas, such as:

• In the province of Santa Cruz, 161 transects were considered in the central plateau area, 7 in the humid Magellanic steppe area, 8 in the dry Magellanic steppe area, and 26 in the "Mata Negra" scrub area.

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


#### **Table 1.**

*Use factor in the different ecological areas, phytogeographic areas, or bioclimatic entities surveyed.*


For the development of the method, different situations were taken and it came to be taken as the most powerful and relevant method to evaluate the flora, including plants, fungi, lichens, and macroalgae (such as macroalgae of the genus *Chara,* very common in pond areas in semideserts) in different situations. We have tested the use of the method for studies of general plant biodiversity, for comparison between different landscape units and for comparison of the same landscape unit throughout the different seasons of the year (spring, summer, autumn, and winter) or throughout of several years, to calculate the receptivity of domestic and/or wild animals, to evaluate the degrees of degradation over the years, or the passive or active ecological restoration of land, to know the degree of conservation of an area, to assess the loss of diversity/productivity/receptivity of flood-prone areas where dams or weirs will be built or where the water course will be diverted, in areas that have suffered clearing, fires or changes in land use, including for opening to livestock or agricultural barrier or road diversions, industrial effluent impacts, and for monitoring loss of native species and/or biological invasions concrete and/or potential, and for mining studies, for evaluation of studies of direct and indirect impacts of various kinds, for studies of ethnobotanical uses, etc. In all cases, the method has proven to be the most powerful for comprehensive assessments of the flora.
