Effects of long-term protection from grazing on phenotypic expression in geographically separated mountain rough fescue populations

Abstract

Thompson, D. J. and Willms, W. D. 2014. Effects of long-term protection from grazing on phenotypic expression in geographically separated mountain rough fescue populations. Can. J. Plant Sci. 94: 33–39. Whether or not long-term grazing or protection from grazing alters the genetic makeup of grass populations has been debated. Mountain rough fescue [(Festuca campestris (Rydb.)], which is highly sensitive to summer grazing, and becomes dominant in plant communities with long-term protection, was chosen to address this question. Plants from three geographic sites (Stavely in AB, Milroy in the Kootenay trench, BC and Goose Lake on the BC interior plateau) with divergent grazing histories were vegetatively propagated from tillers. Daughter plants were planted into two field nurseries (at Kamloops, BC, and Stavely, AB) and morphological measurements were taken in two field seasons post-establishment. Plants from all three populations were taller, flowered earlier, and were more productive at the Kamloops nursery site. Of the three geographic sources, plants from the Goose Lake site were most distinct with narrower leaves, later flowering, and greater yield. Plants with a long history of grazing had slightly shorter fertile tillers and leaves than plants with a history of long-term protection.

Effects of grazing on ecosystem structure and function of alpine grasslands in Qinghai–Tibetan Plateau: a synthesis

“…Some ecological benefits of this program have been reported (Wei et al 2012, Wu et al 2013, but our analyses suggest that complete exclusion of grazing in grassland ecosystems can have variable effects on grassland health with evidence for positive (Wu et al 2010, Yan andLu 2015), negative , and neutral effects (Dong et al 2012, Lu et al 2015a. In other ecosystems, there is growing evidence that complete exclusion from grazing for a prolonged period of time may not lead to an improvement in vegetation and soil conditions (Chaneton and Lavado 1996, Hart and Scientist 2001, Firincio glu et al 2007, Thompson and Willms 2014. From our metadata analysis, low or moderate grazing could be an appropriate alpine grassland management strategy.…”

“…Some ecological benefits have been gained from the RLRG program, but complete exclusion of grazing in grassland ecosystems can have variable effects on grassland health. These observations combined with evidence from studies of grazing systems elsewhere (Firincio glu et al 2007, Kimoto et al 2012, Thompson and Willms 2014 suggest that a more nuanced management regime, such as moderate grazing strategy, may offer the best compromise between balances of ecological protection of grasslands and forage production for livestock in the QTP region.…”

“…In other ecosystems, there is growing evidence that complete exclusion from grazing for a prolonged period of time may not lead to an improvement in vegetation and soil conditions (Chaneton and Lavado , Hart and Scientist , Firincioğlu et al. , Thompson and Willms ). From our metadata analysis, low or moderate grazing could be an appropriate alpine grassland management strategy.…”

“…, Kimoto et al. , Thompson and Willms ) suggest that a more nuanced management regime, such as moderate grazing strategy, may offer the best compromise between balances of ecological protection of grasslands and forage production for livestock in the QTP region.…”