Long-term grazing effects on rough fescue grassland soils in southern British Columbia

2014 ◽  
Vol 94 (3) ◽  
pp. 337-345 ◽  
Author(s):  
Maja Krzic ◽  
Sarah F. Lamagna ◽  
Reg F. Newman ◽  
Gary Bradfield ◽  
Brian M. Wallace

Krzic, M., Lamagna, S. F., Newman, R. F., Bradfield, G. and Wallace, B. M. 2014. Long-term grazing effects on rough fescue grassland soils in southern British Columbia. Can. J. Soil Sci. 94: 337–345. Rough fescue (Festuca campestris Rydb.) is a highly palatable forage species with little resistance to continuous grazing. The objective of this study was to evaluate the effects of long-term cattle grazing on soil properties, above-ground biomass, and canopy cover of key grass species on rough fescue grasslands in the southern interior British Columbia. Soil and vegetation properties were determined on a total of six open grassland sites located at the Lac du Bois and Hamilton Mountain. At all sites, grazing use has decreased over time, with the heaviest grazing occurring prior to 1960. The long-term (25–75 yr) elimination of grazing on these semi-arid grasslands has led to greater above-ground biomass and canopy cover of rough fescue, as well as increased soil polysaccharides; however, no differences in total soil C, N, and aggregate stability were found between pastures with and without grazing. Both soil bulk density and mechanical resistance were greater on grazed plots compared with those without grazing, with differences being more pronounced at the Hamilton Mountain location. The current grazing regime has not allowed for the elimination of negative effects of overgrazing on soil compaction on these rough fescue grasslands, especially at the location that continued to be grazed more heavily (i.e., Hamilton Mountain). Our findings suggest that soils in these grazing-sensitive grasslands need more than 75 yr to fully recover from the impacts of overgrazing.

2012 ◽  
Vol 92 (4) ◽  
pp. 685-693 ◽  
Author(s):  
C. R. W. Evans ◽  
M. Krzic ◽  
K. Broersma ◽  
D. J. Thompson

Evans, C. R. W., Krzic, M., Broersma, K. and Thompson, D. J. 2012. Long-term grazing effects on grassland soil properties in southern British Columbia. Can. J. Soil Sci. 92: 685–693. Although grazing effects on soil properties have been evaluated on various temperate grasslands, no study has dealt with these effects in the southern interior of British Columbia. The objective of this study was to determine the effects of spring versus fall season grazing as well as grazing [at a moderate rate of 0.6 animal unit months (AUM) ha−1] versus non-grazing by beef cattle on selected soil properties. Effects were determined 20 and 30 yr after the establishment of the field experiment. Soil properties were determined for the 0- to 7.5-cm, 7.5- to 15-cm, and 15- to 30-cm depths. In comparison with fall grazing, spring grazing had greater soil bulk density, greater mechanical resistance within the top 15 cm of the soil profile, higher pH, and lower polysaccharides. This was true for both 20 and 30 yr of treatment. Grazing effects on aggregate stability were observed only after 30 yr with spring grazing leading to a more stable structure with a mean weight diameter (MWD) of 1.5 mm and 32% and 10% of aggregates in the 2- to 6-mm and 1- to 2-mm size fractions, respectively, compared with a MWD of 1.0 mm and 20% and 6% under fall grazing. Greater soil bulk density, mechanical resistance, and pH were observed under the grazed treatment relative to the control without grazing, but as we used a moderate stocking rate the impacts were not as great as in previous studies, which used heavy stocking rates. Our findings show that long-term grazing at a moderate stocking rate of 0.6 AUM ha−1did not have critical detrimental effects on soil properties as some land managers and ranchers have suggested.


2015 ◽  
Vol 34 (2) ◽  
pp. 137-146
Author(s):  
Saulius Marcinkonis ◽  
Birutė Karpavičienė ◽  
Michael A. Fullen

AbstractThe aim of the present study is to evaluate the long-term effects of long-term piggery effluent application on semi-natural grassland ecotop-phytotop changes (above- and below-ground phytomass production, and carbon and nitrogen allocation in grassland communities) in relation to changes (or variability) in topsoil properties. Analysis of phytomass distribution in piggery effluent irrigated grassland communities showed that dry biomass yield varied from 1.7−5.3 t ha-1. Variability in soil and plant cover created a unique and highly unpredictable site specific system, where long-term anthropogenic influences established successor communities with specific characteristics of above- and below-ground biomass distribution. These characteristics depend more on grassland communities than on soil chemical properties. Families of grasses (Poaceae) dominated the surveyed communities and accumulated most carbon and least nitrogen, while legumes accumulated most nitrogen and lignin and least carbon. Carbon concentrations in above-ground biomass had minor variations, while accumulation of nitrogen was strongly influenced by species diversity (r = 0.94, n = 10, p <0.001) and production of above-ground biomass


1971 ◽  
Vol 24 (3) ◽  
pp. 185 ◽  
Author(s):  
A. Johnston ◽  
J. F. Dormaar ◽  
S. Smoliak

2011 ◽  
Vol 57 (No. 11) ◽  
pp. 505-512 ◽  
Author(s):  
X. Liu ◽  
W. Zhang ◽  
Z. Liu ◽  
F. Qu ◽  
X. Tang

In order to restore the impaired forest ecosystem in China, great efforts including the banning of the animal grazing and cutting woods for fuel, and implementation of the &lsquo;Grain for Green&rsquo; program have been made by the central and local government of China. The objective of this research was to investigate the changes in above-ground biomass and species diversity after 22 years of vegetation recovery efforts in the lower Taihang Mountain of China. The results indicated that over the natural restoration process shrubs became the dominant species in 2008, while herbs were the dominant species back in 1986. Community coverage, height and above-ground biomass showed significant increases in 2008 compared to 1986. Shrubs showed significant increases in coverage, height, and above-ground biomass, whereas herbs significantly increased in height, but decreased in above-ground biomass. Over the 22-year natural restoration process, the species richness index and the Shannon-Wiener&rsquo;s index had been significantly decreased, whereas the Simpson&rsquo;s predominance index and the Pielou&rsquo;s evenness index had been significantly increased. Long-term vegetation recovery efforts improved the impaired forest ecosystem in lower Taihang Mountain to some extent: significant increases in both community coverage and above-ground biomass. The significant increase in community coverage can reduce the soil loss by wind and water erosion, and increase in the above-ground biomass will improve the soil chemical properties and physical structure. A comprehensive assessment of the success of vegetation recovery should include the evaluation of the changes in ecological process such as soil biological activities in the future research.


2005 ◽  
Vol 58 (6) ◽  
pp. 637-642 ◽  
Author(s):  
Yong-Bi Fu ◽  
Don Thompson ◽  
Walter Willms ◽  
Mairi Mackay

2015 ◽  
Vol 12 (10) ◽  
pp. 2927-2951 ◽  
Author(s):  
E. M. Veenendaal ◽  
M. Torello-Raventos ◽  
T. R. Feldpausch ◽  
T. F. Domingues ◽  
F. Gerard ◽  
...  

Abstract. Through interpretations of remote-sensing data and/or theoretical propositions, the idea that forest and savanna represent "alternative stable states" is gaining increasing acceptance. Filling an observational gap, we present detailed stratified floristic and structural analyses for forest and savanna stands located mostly within zones of transition (where both vegetation types occur in close proximity) in Africa, South America and Australia. Woody plant leaf area index variation was related to tree canopy cover in a similar way for both savanna and forest with substantial overlap between the two vegetation types. As total woody plant canopy cover increased, so did the relative contribution of middle and lower strata of woody vegetation. Herbaceous layer cover declined as woody cover increased. This pattern of understorey grasses and herbs progressively replaced by shrubs as the canopy closes over was found for both savanna and forests and on all continents. Thus, once subordinate woody canopy layers are taken into account, a less marked transition in woody plant cover across the savanna–forest-species discontinuum is observed compared to that inferred when trees of a basal diameter > 0.1 m are considered in isolation. This is especially the case for shrub-dominated savannas and in taller savannas approaching canopy closure. An increased contribution of forest species to the total subordinate cover is also observed as savanna stand canopy closure occurs. Despite similarities in canopy-cover characteristics, woody vegetation in Africa and Australia attained greater heights and stored a greater amount of above-ground biomass than in South America. Up to three times as much above-ground biomass is stored in forests compared to savannas under equivalent climatic conditions. Savanna–forest transition zones were also found to typically occur at higher precipitation regimes for South America than for Africa. Nevertheless, consistent across all three continents coexistence was found to be confined to a well-defined edaphic–climate envelope with soil and climate the key determinants of the relative location of forest and savanna stands. Moreover, when considered in conjunction with the appropriate water availability metrics, it emerges that soil exchangeable cations exert considerable control on woody canopy-cover extent as measured in our pan-continental (forest + savanna) data set. Taken together these observations do not lend support to the notion of alternate stable states mediated through fire feedbacks as the prime force shaping the distribution of the two dominant vegetation types of the tropical lands.


2010 ◽  
Vol 70 (2) ◽  
pp. 395-404 ◽  
Author(s):  
A. Souza ◽  
CZ. Sandrin ◽  
MFA. Calió ◽  
ST. Meirelles ◽  
VR. Pivello ◽  
...  

Echinolaena inflexa (Poir.) Chase is an abundant C3 grass species with high biomass production in the Brazilian savanna (cerrado); Melinis minutiflora Beauv. is an African C4 forage grass widespread in cerrado and probably displacing some native herbaceous species. In the present work, we analysed seasonally the content and composition of soluble carbohydrates, the starch amounts and the above-ground biomass (phytomass) of E. inflexa and M. minutiflora plants harvested in two transects at 5 and 130 m from the border in a restrict area of cerrado at the Biological Reserve and Experimental Station of Mogi-Guaçu (SP, Brazil). Results showed that water soluble carbohydrates and starch amounts from the shoots of both species varied according to the time of the year, whilst in the underground organs, variations were observed mainly in relation to the transects. Marked differences in the pattern of the above-ground biomass production between these two grasses relative to their location in the Reserve were also observed, with two peaks of the invasive species (July and January) at the Reserve border. The differences in carbohydrate accumulation, partitioning and composition of individual sugars concerning time of the year and location in the Reserve were more related to the annual growth cycle of both grasses and possibly to specific physiological responses of M. minutiflora to disturbed environments in the Reserve border.


Biologia ◽  
2009 ◽  
Vol 64 (4) ◽  
Author(s):  
Ivan Tůma ◽  
Petr Holub ◽  
Karel Fiala

AbstractWe studied the effects of differences in root growth and nutrient pool on the competitive ability of Festuca ovina (short grass), Arrhenatherum elatius and Calamagrostis epigejos (tall grasses) grown in monocultures and in mixtures of homogeneous and heterogeneous environments during two growing seasons. Analysis of variance revealed a significant effect of plant species on nutrient concentrations in above-ground biomass and of substrate type on contents of N, K, Ca, Mg in biomass. The ANOVA also confirmed the significant effect of competitive environment on the concentration of N, K in above-ground biomass. In heterogeneous environments, both tall grasses (in competition with F. ovina) were able to produce more roots in the nutrient-rich patches and to accumulate more nitrogen in plant tissues, which was associated with higher yield of their above-ground biomass. Thus, the relative competitive ability for nutrients of both tall grasses was higher than that of F. ovina. This competitive ability of A. elatius to C. epigejos increased in heterogeneous treatments.


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