Sustainability of holistic and conventional cattle ranching in the seasonally dry tropics of Chiapas, Mexico

Highlights

• We compared management and ecological outcomes on holistic and conventional ranches.

• Holistic ranchers use rotational grazing, minimize purchased inputs and do not burn.

• Their pastures have denser grass, deeper topsoil, and more earthworms.

• Holistic management is leading to greater ecological and economic sustainability.

Abstract

Conventional cattle ranching in the lowlands of Chiapas, Mexico typically employs extensive grazing, annual pasture burns and frequent applications of agrochemicals, threatening biodiversity and long-term productivity. A small group of innovative ranchers in the Central Valleys are converting to holistic management through careful land-use planning, rotational grazing, diversified forage, and diminished use of purchased inputs. We compared the sustainability of 18 conventional and seven holistic, dual-purpose ranches, using three sets of sustainability metrics. First, we combined semistructured interviews and field observations to better describe the two productions systems and to calculate an “Organic Conversion Index” (OCI), combining economic, social, technological and environmental indicators. Holistic ranchers have more pasture divisions, higher grazing pressure, greater lengths of time between pasture burns, greater milk productivity, larger forest reserves, lower cow and calf mortality, purchase less hay and feed, and use less herbicides and pesticides than their conventional neighbors (T-tests and Fisher’s Exact Tests; all p < 0.05). OCI was greater (T-test, p < 0.0005) for holistic ranches (81.8 ± 4.6% compliance with organic standards), than for conventional ranches (32.1 ± 9.0% compliance), with holistic ranches demonstrating superiority for nine of ten OCI indicators. Second, drawing on data from the same interviews, we conducted “emergy” analysis to quantify the embodied energy of inputs, outputs and sustainability of the ranching systems. The Emergy Yield Ratio, an index of a systems emergy throughput relative to the emergy in purchased inputs, was marginally higher in holistic ranches (T-test; p = 0.07), but became significant when only ranches ⩾40 ha were analyzed (p = 0.04) and when government assistance (mostly in the form of machinery) was removed from the calculations (p = 0.008). Holistic ranches exhibited marginally higher Emergy Sustainability Indices, a measure of system yield relative to environmental impact, for all ranches combined (p = 0.07) and for ranches ⩾ 40 ha (p = 0.06). Third, we sampled vegetation and soils on seven holistic and seven conventional ranches. We found higher soil respiration, deeper topsoil, increased earthworm presence, more tightly closed herbaceous canopies (all p < 0.05), and marginally greater forage availability (p = 0.053) in holistic ranches. Other variables, including soil compaction, soil chemistry and pasture tree cover, did not differ significantly between groups. These data are a snapshot of long, complex processes. Nonetheless, these complementary metrics combine to suggest that holistic management strategies are leading to greater ecological and economic sustainability. This production model merits further study for potential broader application as well as greater attention from decision makers concerned with ranching and the environment.

Introduction

Livestock production is among the fastest growing economic sectors in the developing world (Delgado et al., 1999, Steinfeld et al., 2006) and constitutes a pillar of the rural economy in Chiapas (Jiménez Ferrer et al., 2003). Raising livestock contributes to the food sovereignty of farm families and is a savings strategy for small producers that allows them to confront emergencies and better capitalize on their production systems (Delgado et al., 1999, Jiménez Ferrer et al., 2003, Kaimowitz, 1996). Extensive ranching is also attractive to large producers as labor costs are low in relation to the land area managed (Hecht, 1993, Kaimowitz, 1996, White et al., 2001).

Cattle ranching in tropical Latin America has been based largely on extensive monocultures of grass, a production model poorly suited to the region (Murgueitio et al., 2011, Sánchez et al., 2000). These artificial grasslands are inefficient and fragile, exhibiting low productivity and nutritional value while being highly susceptible to soil and pasture degradation, especially when subjected to over- or under-grazing (Van Soest, 1982, Savory and Butterfield, 1999, Serrão and Toledo, 1990, Szott et al., 2000). This deficiency is particularly marked during the dry season, when ranchers must allow livestock to forage over a larger area and/or increase feed supplements (Szott et al., 2000), increasing their negative impact.

Frequent burns exacerbate pasture degradation and threats to the surrounding landscape. Pasture burns provide multiple short-term benefits, including elimination of unpalatable plants and lignified grass, promotion of tender new grass growth, a pulse of nutrients released into the soil and control of herbivorous insects, plant pathogens and ticks (Savory and Butterfield, 1999, Villanueva Avalos et al., 2008). However, burns can also diminish soil fertility and the structural and biological diversity of the plant community (Savory and Butterfield, 1999, Vieira and Scariot, 2006). These fires often get out of control, burning neighboring forests and farms (Román-Cuesta et al., 2003).

The combination of low productivity, rapid degradation and fire contributes to the extensive nature of tropical cattle ranching, and its association with deforestation and biodiversity loss (FAO/EMBRAPA, 2001, Murgueitio et al., 2011, Villafuerte et al., 1997). Soil and pasture degradation and biodiversity loss lead to increased dependence on herbicides, pesticides, fertilizers and feed supplements, which in turn reduces profit margins.

In the face of these limitations, a small group of dual-purpose (milk and meat) ranchers in the Central Valleys of Chiapas have turned to the holistic management (HM) decision-making framework described by Savory and Butterfield (1999). Under HM, management decisions are based upon relationships among the landscape (including wild and managed biodiversity, water, soil and other resources), people (farmers and ranchers and their families, neighbors, suppliers, customers, advisers, regulators and so on), the broader community in which they live, and the services available in that community. In “brittle” environments like our study area, where humidity is particularly uneven throughout the year, HM advocates managing high densities of large herding animals to produce heavy grazing and trampling impact for brief periods at appropriate intervals.

With support and training from FIRA (Avalos Flores et al., 1996), visiting Cuban extensionists and faculty at the Autonomous University of Chiapas, the ten ranchers formed an “Intensive, Technical Grazing” club (“PIT Las Villas”) in 1994. Seven of the original club members continue to practice HM. Core elements of their management strategy include: holistic decision making, farmer-to-farmer training, Voisin-style rotational grazing (Voisin, 1959), reduction in the frequency of burns, major reductions in agrochemical use, careful record keeping, diversification of forage resources and maintenance of forest reserves.

Proponents of HM present empirical evidence of its potential for simultaneously improving productivity and protecting the environment (Savory and Butterfield, 1999, www.holisticmanagement.org). However HM has not been widely studied from a scientific perspective and findings have been contradictory (Teague et al., 2011). To evaluate HM’s sustainability, we compared the ranches of the members of PIT Las Villas with those of their “conventional” neighbors using three sets of metrics: compliance with organic standards used to calculate an Organic Conversion Index (OCI), emergy analysis of inputs, outputs and overall sustainability, and measurement of vegetation diversity and soil parameters that indicate system health.