ecosystem services to and from north american arid ... - Conabio

More documents

Recommendations

Info

IV SIMPOSIO INTERNACIONAL DE PASTIZALES San Luis Potosí, S.L.P. México; 22 al 24 de agosto de 2007 Artículos in extenso Área temática: Transferencia de Tecnología COMMON GRAZING RANGELANDS IN MÉXICO. LIMITING FACTORS FOR SUCCESSFUL UTILIZATION Quero 1 *, C. A. R.; L. Miranda 1 J., A. Hernández G 1 ., and M. Mellado 2 B. 1 Campus San Luis Potosí. Colegio de Postgraduados en Ciencias Agrícolas. Iturbide 73, Salinas, SLP.78600, México. queroadrian@colpos.mx; queroadrian@hotmail.com; tel/fax +52-496-9630240 2 Animal Sciences Department. Universidad Autónoma Agraria “Antonio Narro”. Buenavista, Saltillo, Coahuila, México ABSTRACT Extensive grazing production systems, managed in a sustainable manner, are the natural aptitude suitable for Mexican arid lands for renewable richness production. There is not better option for higher inputs under grazing conditions than the achievement of the best grassland condition for animal production. Asian and African successful communal grazing societies have been based on unanimous respect to grazing rules, supported by practical experience and the interest of communal leaders to resources preservation. These organizational aspects to graze, have been absent within the Mexican common grazing lands. During four generations of massive access to land property in Mexico, Ejido land has provoked the reduction of the primary production potential for the rangeland with the consequent desert advancement. An influential factor for rangeland degradation is the fact that Ejido’s free grazers, who own most of the rangeland vegetation harvesting tools (cattle), show no interest on efficiency neither on resources conservation. There is an important lack of rules for common rangeland resources utilization, annihilating both the individual initiatives to improve the rangeland as well as the utilization, for the rangeland improvement, of the very valuable expertise acquired through first hand experience during daily activities within the rangeland. Drought and low winter temperatures are constant conditions in arid rangelands; hence, all the activities must be adjusted to its continuous presence. In order to impact rangeland conditions basic short-term and low-cost goals for rangeland utilization should be established, among these are: rules for grassland resources utilization, free grazers elimination, promotion for cultural activities (favoring the grassland stability), and an equal rangeland benefits and products distribution among the land shareholders. There is an important technology gap to establish perennial valuable forage species under rain-fed conditions which requires attention, mainly for cropping land reclamation under rain-fed conditions. Grazing management, land tenure, and social aspects have affected rangeland resources conservation and productivity within the arid lands of Mexico. Key words: common grazing, rangeland desertification, ejido grazing, arid rangeland management, grazing philosophy. INTRODUCTION It is well known that land tenure (Singelmann, 1978; Gates, 1988) as well as agricultural and rangeland products commercialization schemes (Liverman, 1990), in Mexico have deeply affected the stability of arid lands, the economy of peasants, the opportunities for rangeland improvement. During colonial times, Mexican rangelands were an important richness source, due to the fact that its use, was defined by several factors: wild animals, frequent wars, violent 208
IV SIMPOSIO INTERNACIONAL DE PASTIZALES San Luis Potosí, S.L.P. México; 22 al 24 de agosto de 2007 Artículos in extenso Área temática: Transferencia de Tecnología native groups, cattle thieves, isolation, as well as the hacendado’s unique management decisions on land resources utilization. Nowadays, Mexican rangelands have become an important cheap hand labor producer, mainly after 1940, reducing life quality, education, health and nutritive opportunities for the rangeland inhabitants in a constant manner (Baer, 1990). The non-existent concern for the energy fluxes of the rangeland has caused a degradation of grazing lands and has substantially eroded genetic resources (plant/animal); this situation favors or brings about soil erosion, drastic changes in population composition (predominance of women, elderly people, and children) within the rangeland villages, and it also promotes extreme poverty among the semiarid rangelands inhabitants. The importance for sustainable agriculture in the dry Mexican ecosystems has been widely indicated (Muñoz, 2002); however, before the implementation of any rangeland development project, it is important to characterize each particular production system. It is essential to prevent that rangeland-supporting programs become eternal palliatives, that do not reach the population or the rangeland condition (Thoms and Betters, 1998; Lynam, 2005). Although there is a myriad of available technology to support rangeland improvement in Mexico, the lack of economic and technological risk capacity from the peasants have affect the opportunities to arrest desertification advancement. Several experiences and ideas do exist about how to reach the rangeland condition and support its improvement. The objectives of this review are to expose the author´s ideas to support the rangeland and inhabitants opportunities for integral development. Plants for grazing Native range plant communities are well adapted to recurrent droughts and winter temperatures, which constitute the main limiting production factor for the arid rangelands vegetation (Briske, 1991). Low temperatures as well as drought cause that the grasses, important forage source, enter in dormancy; thus photosynthesis and productivity are reduced. If the rainy season is good, vigorous species, achieved through good grazing management, will render higher forage production and better quality levels for longer periods, as well as other ecological benefits. Grass ability to endure drought, within arid ecosystems, is probably related to a high level of water infiltration due to the water flux from stems as well as the retained run-off among tillers (Nash et al., 2003). Hence, a sound extensive grazing production system is indicated for these rangeland production schemes. Scarce rain-fed crop production under scattered and poor rain events, characteristic of arid lands, as well as the high cost of irrigation infrastructure, defines extensive grazing production as the main income source for huge land surfaces within northern Mexico’s rangelands. On the other hand, ruminants represent the basic mean to transform sun energy caught by plants into protein and valuable byproducts through grazing. Hence, it is important to review, on a regular basis, the aspects that define actual rangeland condition as well as requirements to enhance plant productivity and persistence within the grassland. Although grazing per se does not condition the desertification process (Evans and Geerken, 2004), Mexican grazing production systems do not maintain a stocking rate according to forage availability; and this is worsened by the high risk agriculture, stubble grazing, common land property, and a poor cattle production culture or technology. One of the factors favoring that the arid rangeland grazing production becomes a devastating tool for the ecosystem is: the lack of rules to use common or shared resources, and this has reduced the income of the population who depends on it. Within arid rangelands, a perennial grasses higher cover is a good organic matter and water retention indicator (de Soyza et al., 1997). Excessive trampling or consumption will eliminate the main supporting factors increasing wind and water effects as erosion determinants: plant span (Van de Ven et al., 1989), plant nutrient reserves for survival, as well as the C source for soil microbial 209
Page 1 and 2:
IV SIMPOSIO INTERNACIONAL DE PASTIZ
Page 3 and 4:
Page 5 and 6:
Page 7 and 8:
Page 9 and 10:
Page 11 and 12:
Page 13 and 14:
Page 15 and 16:
Page 17 and 18:
Page 19 and 20:
Page 21 and 22:
Page 23 and 24:
Page 25 and 26:
Page 27 and 28:
Page 29 and 30:
Page 31 and 32:
Page 33 and 34:
Page 35 and 36:
Page 37 and 38:
Page 39 and 40:
Page 41 and 42:
Page 43 and 44:
Page 45 and 46:
Page 47 and 48:
Page 49 and 50:
Page 51 and 52:
Page 53 and 54:
Page 55 and 56:
Page 57 and 58:
Page 59 and 60:
Page 61 and 62:
Page 63 and 64:
Figura 1. Porcentajes de germinaci
Page 65 and 66:
Page 67 and 68:
Page 69 and 70:
160 140 120 100 80 60 40 20 0 ENE I
Page 71 and 72:
Page 73 and 74:
Page 75 and 76:
Page 77 and 78:
Page 79 and 80:
Page 81 and 82:
Page 83 and 84:
Page 85 and 86:
Page 87 and 88:
Page 89 and 90:
Page 91 and 92:
Page 93 and 94:
Page 95 and 96:
Page 97 and 98:
Page 99 and 100:
Page 101 and 102:
Page 103 and 104:
Page 105 and 106:
Page 107 and 108:
Page 109 and 110:
Page 111 and 112:
Page 113 and 114:
Page 115 and 116:
Page 117 and 118:
Page 119 and 120:
Page 121 and 122:
Page 123 and 124:
Page 125 and 126:
Page 127 and 128:
Page 129 and 130:
Page 131 and 132:
Page 133 and 134:
Page 135 and 136:
Page 137 and 138:
Page 139 and 140:
50 cm 30 cm IV SIMPOSIO INTERNACION
Page 141 and 142:
Page 143 and 144:
Page 145 and 146:
Page 147 and 148:
Page 149 and 150:
Page 151 and 152:
Page 153 and 154:
Page 155 and 156: IV SIMPOSIO INTERNACIONAL DE PASTIZ
Page 157 and 158: N IV SIMPOSIO INTERNACIONAL DE PAST
Page 165 and 166: MS (kg/ha) 3500 3000 2500 2000 1500
Page 205: IV SIMPOSIO INTERNACIONAL DE PASTIZ
Page 257 and 258:
Page 259 and 260:
Page 261 and 262:
Page 263 and 264:
Page 265 and 266:
Page 267 and 268:
show all

ecosystem services to and from north american arid ... - Conabio

Create successful ePaper yourself

Delete template?

Save as template?