|Herrick, Jeffrey - Jeff|
Submitted to: Society for Range Management Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 10/5/2004
Publication Date: 2/5/2005
Citation: Melgoza, A., Royo, M., Herrick, J.E. 2005. Efforts to evaluate range health in northern Mexico [abstract]. 58th Annual Meeting of the Society for Range Management. February 5-11,2005, Fort Worth, Texas. Abstract No. 228. Interpretive Summary: Feral horse impacts on soils are virtually unknown. Wild horses are common in many areas of the Great Basin of the western United States. We compared soil-surface hardness and abundance of ant mounds in areas grazed by feral horses (Equus caballus) with areas from which horses were removed in the last 10-14 years. The study was completed in nine different mountain ranges. During both 1997 and 1998, we found greater abundance of ant mounds and lower penetration resistance in soil surfaces at horse-removed sites. The results suggest that horse removal is likely to improve lead to improved soil quality in Great Basin ecosystems.
Technical Abstract: Rangeland health evaluations provide specialists with an important tool that can be used to help increase rangeland sustainability. There are several publications for evaluation and monitoring of single products and or services; however, an integrated ecological approach is more appropriate where rangeland is managed to support multiple objectives. A US interagency group with significant input from INIFAP (Mexico) scientists has developed an integrated ecological approach based on three ecological attributes: soil and site stability, hydrologic function, and biotic integrity. These attributes are evaluated using 17 qualitative indicators. The qualitative evaluations can be supported by a number of quantitative measurements, which can also be used for monitoring. Six workshops have been conducted in Mexico, where approximately 200 participants have been trained. Ranchers, several protected areas, and research projects are using this methodology. Evaluation of a site is made based on a reference sheet that is developed for a suite of similar soils. In the past, reference areas were often used in place of the reference sheet. However, it is often not possible to find an appropriate reference area, and reliance on individual reference areas ignores other valuable knowledge sources. The process of completing the reference sheets often leads to the identification of knowledge gaps that can be addressed with research. Current challenges include developing consistent terminology, methods, analysis, and interpretation. There is a great opportunity to share experiences and strategies for increasing the accuracy and efficiency of the application of this protocol on both sides of the border.