Competition indices of three perennial grasses used to rehabilitate degraded semi-arid rangelands in Kenya
K. Z. Mganga A C , N. K. R. Musimba A and D. M. Nyariki BA Department of Range and Wildlife Sciences, South Eastern Kenya University, PO Box 170-90200, Kitui, Kenya.
B Department of Agricultural Economics and Agribusiness, South Eastern Kenya University, PO Box 170-90200, Kitui, Kenya.
C Corresponding author. Emails: kzowe@yahoo.com, kmganga@seku.ac.ke
The Rangeland Journal 37(5) 489-495 https://doi.org/10.1071/RJ15023
Submitted: 13 March 2015 Accepted: 20 August 2015 Published: 7 October 2015
Abstract
Rangeland degradation is one of the most serious environmental challenges in arid and semi-arid environments in Africa. Grass reseeding technology, using indigenous perennial grass species has a great potential for restoring ecosystem functionality in these degraded lands. This study was aimed at investigating how the establishment of indigenous grasses used to rehabilitate degraded semi-arid rangelands in Kenya as monocultures or binary mixtures affect dry matter biomass yields and plant competition indices at different phenological stages of development: seedling, elongation and reproduction. Using plant competition indices, we demonstrated which among these grass species showed a complementary vis-à-vis competitive interaction in binary mixtures across their phenological stages. Monocultures and binary mixtures of three perennial grass species: Cenchrus ciliaris L. (Buffel grass), Enteropogon macrostachyus Munro ex Benth. (Bush ryegrass) and Eragrostis superba Peyr. (Wilman lovegrass) native to these semi-arid rangelands were established in a field experiment. Pure stands of E. macrostachyus yielded higher biomass than C. ciliaris and E. superba only at the seedling and elongation phases but not the reproduction phase, where the yields were lowest among pure stands. Negative plant interactions in binary mixtures were observed at seedling and reproduction stages, compared with positive interactions observed at the elongation phase. Binary grass mixtures had a significant advantage for exploiting available environmental resources only at the elongation phase but not at the seedling and reproduction phases. Based on the estimated competition indices, E. superba best complements C. ciliaris across the phenological stages. We therefore conclude that this binary mixture is the one most likely to ensure successful rehabilitation of degraded semi-arid rangelands in this region.
Additional keywords: Cenchrus ciliaris, competition indices, Enteropogon macrostachyus, Eragrostis superba, semi-arid rangelands.
References
Bhattarai, S. P., Fox, J., and Gyasi-Agyei, Y. (2008). Enhancing buffel grass seed germination by acid treatment for rapid vegetation establishment on railway batters. Journal of Arid Environments 72, 255–262.| Enhancing buffel grass seed germination by acid treatment for rapid vegetation establishment on railway batters.Crossref | GoogleScholarGoogle Scholar |
Bond, W. J., Honig, M., and Maze, K. E. (1999). Seed size and seedling emergence: an allometric relationship and some ecological implications. Oecologia 120, 132–136.
| Seed size and seedling emergence: an allometric relationship and some ecological implications.Crossref | GoogleScholarGoogle Scholar |
Catchpole, W. R., and Wheeler, C. J. (1992). Estimating plant biomass: a review of techniques. Australian Journal of Ecology 17, 121–131.
| Estimating plant biomass: a review of techniques.Crossref | GoogleScholarGoogle Scholar |
Daehler, C. C., and Goergen, E. M. (2005). Experimental restoration of an indigenous Hawaiian grassland after invasion by buffel grass (Cenchrus ciliaris). Restoration Ecology 13, 380–389.
| Experimental restoration of an indigenous Hawaiian grassland after invasion by buffel grass (Cenchrus ciliaris).Crossref | GoogleScholarGoogle Scholar |
Dhima, K. V., Vasilakoglou, I. B., Xh Keco, R., Dima, A. K., Paschalidis, K. A., and Gatsis, T. D. (2013). Forage yield and competition indices of faba bean intercropped with oat. Grass and Forage Science 69, 376–383.
| Forage yield and competition indices of faba bean intercropped with oat.Crossref | GoogleScholarGoogle Scholar |
Donath, T. W., and Eckstein, R. L. (2010). Effects of bryophytes and grass litter on seedling emergence vary by vertical seed position and seed size. Plant Ecology 207, 257–268.
| Effects of bryophytes and grass litter on seedling emergence vary by vertical seed position and seed size.Crossref | GoogleScholarGoogle Scholar |
El-Kharbotly, A., Mahgoub, O., Al-Subhi, A., and Al-Halhali, A. (2003). Indigenous grass species with potential for maintaining rangeland and livestock feeding in Oman. Agriculture, Ecosystems & Environment 95, 623–627.
| Indigenous grass species with potential for maintaining rangeland and livestock feeding in Oman.Crossref | GoogleScholarGoogle Scholar |
Hussain, F., Ahmad, B., and Ilahi, I. (2010). Allelopathic effects of Cenchrus ciliaris L. and Bothriocloa pertusa (L.) A. Camus. Pakistan Journal of Botany 42, 3587–3604.
Jackson, J. (2005). Is there a relationship between herbaceous species richness and buffel grass (Cenchrus ciliaris)? Austral Ecology 30, 505–517.
| Is there a relationship between herbaceous species richness and buffel grass (Cenchrus ciliaris)?Crossref | GoogleScholarGoogle Scholar |
Leishman, M. R., and Westoby, M. (1994). The role of seed size in seedling establishment in dry soil conditions – experimental evidence from semi-arid species. Journal of Ecology 82, 249–258.
| The role of seed size in seedling establishment in dry soil conditions – experimental evidence from semi-arid species.Crossref | GoogleScholarGoogle Scholar |
Marshall, V. M., Lewis, M. M., and Ostendorf, L. B. (2012). Buffel grass (Cenchrus ciliaris) as an invader and threat to biodiversity in arid environments: a review. Journal of Arid Environments 78, 1–12.
| Buffel grass (Cenchrus ciliaris) as an invader and threat to biodiversity in arid environments: a review.Crossref | GoogleScholarGoogle Scholar |
Mekuria, W., and Aynekulu, E. (2013). Exclosure land management for restoration of the soils in degraded communal grazing lands in northern Ethiopia. Land Degradation & Development 24, 528–538.
| Exclosure land management for restoration of the soils in degraded communal grazing lands in northern Ethiopia.Crossref | GoogleScholarGoogle Scholar |
Mganga, K. Z., Musimba, N. K. R., Nyangito, M. M., Nyariki, D. M., and Mwang’ombe, A. W. (2010). Improving hydrological responses of degraded soils in semi-arid Kenya. Journal of Environmental Science and Technology 3, 217–225.
| Improving hydrological responses of degraded soils in semi-arid Kenya.Crossref | GoogleScholarGoogle Scholar |
Mganga, K. Z., Musimba, N. K. R., Nyariki, D. M., Nyangito, M. M., and Mwang’ombe, A. W. (2015). The choice of grass species to combat desertification in semi-arid Kenyan rangelands is greatly influenced by their forage value for livestock. Grass and Forage Science 70, 161–167.
| The choice of grass species to combat desertification in semi-arid Kenyan rangelands is greatly influenced by their forage value for livestock.Crossref | GoogleScholarGoogle Scholar |
Mureithi, S. M., Verdoodt, A., Njoka, J. T., Gachene, C. K. K., and van Ranst, E. (2015). Benefits derived from rehabilitating a degraded semi-arid rangeland in communal enclosures, Kenya. Land Degradation & Development , .
| Benefits derived from rehabilitating a degraded semi-arid rangeland in communal enclosures, Kenya.Crossref | GoogleScholarGoogle Scholar |
Mwang’ombe, A. W., Ekaya, W. N., Muiru, W. M., Wasonga, V. O., Mnene, W. N., Mongare, P. N., and Chege, S. W. (2011). Livelihoods under climate variability and change: an analysis of the adaptive capacity of rural poor to water scarcity in Kenya’s drylands. Journal of Environmental Science and Technology 4, 403–410.
| Livelihoods under climate variability and change: an analysis of the adaptive capacity of rural poor to water scarcity in Kenya’s drylands.Crossref | GoogleScholarGoogle Scholar |
Nyangito, M. M., Musimba, N. K. R., and Nyariki, D. M. (2009). Hydrological properties of grazed perennial swards in semi-arid southeastern Kenya. African Journal of Environmental Science and Technology 3, 26–33.
Opiyo, F. E. O., Ekaya, W. N., Nyariki, D. M., and Mureithi, S. M. (2011). Seed-bed preparation influence on morphometric characteristics of perennial grasses of a semi-arid rangeland in Kenya. African Journal of Plant Science 5, 460–468.
Szumigalski, S. M., and van Acker, R. (2005). Weed suppression and crop production in annual intercrops. Weed Science 53, 813–825.
| Weed suppression and crop production in annual intercrops.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXhtlalt77F&md5=d55fbe6e2b2eb77764578ab9bfd4c1f2CAS |
Turner, M. D., and Hiernaux, P. (2002). The use of herders’ accounts to map livestock activities across landscapes in semi-arid Africa. Landscape Ecology 17, 367–385.
| The use of herders’ accounts to map livestock activities across landscapes in semi-arid Africa.Crossref | GoogleScholarGoogle Scholar |
Vilà, M., Williamson, M., and Lonsdale, M. (2004). Competition experiments on alien weeds with crops: lessons from measuring plant invasion impact? Biological Invasions 6, 59–69.
| Competition experiments on alien weeds with crops: lessons from measuring plant invasion impact?Crossref | GoogleScholarGoogle Scholar |
Voigt, P. W., and Tischler, C. R. (1997). Effect of seed treatment on germination and emergence of 3 warm-season grasses. Journal of Range Management 50, 170–174.
| Effect of seed treatment on germination and emergence of 3 warm-season grasses.Crossref | GoogleScholarGoogle Scholar |
Weigelt, A., and Jolliffe, P. (2003). Indices of plant competition. Journal of Ecology 91, 707–720.
| Indices of plant competition.Crossref | GoogleScholarGoogle Scholar |
Yahuza, I. (2011). Review of some methods of calculating intercrop efficiencies with particular reference to the estimates of intercrop benefits in wheat/faba bean system. International Journal of Biosciences 5, 18–30.
