Herbaceous plant richness and vegetation cover in Mediterranean grasslands and shrublands

Casado, Miguel; Castro, Isabel; Ramírez-Sanz, L.; Costa-Tenorio, M.; Miguel, Jesús M. de; Pineda, Francisco Díaz

doi:10.1023/b:vege.0000019021.62054.62

Cited by 53 publications

(33 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Hence, the varied findings of the limited number of studies that have examined this issue in forest understory communities, some of which have found positive productivity-diversity relationships (Williams et al 1996;Adkison and Gleeson 2004;Chen et al 2004), whereas others have found negative (Enica-Dominguez et al 2007) or unimodal (Casado et al 2004;Gomez-Aparicio et al 2009;Speziale et al 2010) relationships. In our present study, a positive relationship between rainfall and UWV species richness was found throughout most of the rainfall gradient with, possibly, a moderate decrease in the rate of richness increase with increasing rainfall at the higher rainfall levels.…”

Section: Understory Species Diversitymentioning

confidence: 92%

“…However, there has been little study of the extent to which woody vegetation structure in these systems is related to rainfall amount or of the pattern of such a relationship. Furthermore, although patterns of variation of vegetation structure along productivity gradients have been studied quite extensively in various parts of the world (Jennings et al 2005;Partel et al 2007), including the Mediterranean region (Kadmon and Danin 1999;Kutiel et al 2000;Casado et al 2004), the variation in forest understory structure along natural productivity gradients has been addressed far less. Understanding variations in forest understory structure along climatic gradients is often complicated because climatic factors are usually confounded with other factors such as silvicultural strategy and history (Maestre and Cortina 2004;Takafumi and Hiura 2009) and overstory characteristics (Barbier et al 2008;Gomez-Aparicio et al 2009).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Understory woody vegetation in manmade Mediterranean pine forests: variation in community structure along a rainfall gradient

et al. 2011

View full text Add to dashboard Cite

Natural regeneration that occurs in the understory of Mediterranean pine monocultures provides the basis for the transition of these simply structured systems toward a more complex and sustainable state. However, the course and consequences of this process, and its relationships with environmental and silvicultural variables, are still inadequately understood. We investigated the relationship between rainfall amount and understory woody vegetation (UWV) structure in mature (40-50 year) Pinus halepensis plantations in the Mediterranean zone of Israel, where rainfall ranges from 280 mm/year in the south to 900 mm/year in the north. We measured abundance, diversity and species composition on south-and northfacing slopes, in forest sites distributed along the rainfall gradient. UWV abundance, as measured by cover percentage and height, increased with rainfall amount along the entire gradient (2-113% and 0.1-3.4 m, respectively), more rapidly on north-facing slopes. Species composition varied along the rainfall gradient, with ranges of species occurrences corresponding to those in unforested habitats. The relationship between rainfall and UWV species richness was positive throughout most of the rainfall gradient, possibly with a shift in pattern at the highest rainfall levels. UWV richness increased sharply with increasing abundance, up to a certain point with no further increase in richness as abundance increased further. We concluded that UWV structure in the studied forest environment and climatic range is strongly determined by rainfall and suggested that the design and management of Mediterranean forests should focus more on optimizing water availability for the various components.

show abstract

Section: Understory Species Diversitymentioning

confidence: 92%

Section: Introductionmentioning

confidence: 99%

Understory woody vegetation in manmade Mediterranean pine forests: variation in community structure along a rainfall gradient

et al. 2011

View full text Add to dashboard Cite

show abstract

“…The high basal cover in the study area could be associated with reduced soil erosion by 3.3% and reduced encroaching tree species densities which created a conducive environment for recruiting new grass species. Furthermore, canopy gaps created by tree/shrub removal are expected to result in increased herbaceous cover, diversity and abundance due to reduced competition for water and nutrients as well as increased availability of light (Casado et al 2004). In line with this finding, Karuaera (2011) found that nonencroached sites had a higher grass cover than the bush-encroached sites.…”

Section: Bush Control Effects On Vegetation Structure and Basal And Lmentioning

confidence: 99%

Control of bush encroachment in Borana zone of southern Ethiopia: effects of different control techniques on rangeland vegetation and tick populations

et al. 2014

View full text Add to dashboard Cite

A study on effects of bush encroachment control techniques on rangeland productivity and tick population dynamics was conducted in Arero district of Borana zone, southern Ethiopia, for three consecutive years. The study targeted two main and dominant encroaching bush species in Borana rangeland, Acacia drepanolobium and Acacia mellifera, and their effects on some vegetation attributes and tick population dynamics. A hectare of rangeland encroached by these two acacia species was replicated/divided into three plots, and each plot was subdivided into five sub-plots to receive five treatments: cutting at 0.5 m above ground and pouring kerosene on stumps (T1), cutting at 0.5 m above ground and debarking the stumps down into the soil surface (T2), cutting at 0.5 m above ground alone (T3), cutting at 0.5 m above ground and dissecting the stumps (T4) and control (T5). Data on basal and litter covers, soil erosion and compaction, dead and re-sprouted encroaching tree/shrub species and nymphand adult-stage tick populations were collected before and after treatment applications. The applied treatments significantly influenced (p < 0.05) basal cover, nymph-and adult-stage tick population and the two encroaching tree species. The results of this study showed that T3 and T2 were good in controlling A. drepanolobium in that order. T4 and T2 had a significant effect in controlling A. mellifera in their order. Controlling bush encroachment had also a positive effect in eradicating the tick population. The most dominant grass and non-grass species observed after the control actions were Cenchrus ciliaris, Chrysopogon aucheri, Abutilon hirtum, Pennisetum mezianum, Dyschoriste hildebrandtii, Zaleya pentandra and Eragrostis papposa. Therefore, controlling encroaching tree/shrub species had created a conducive grazing area with palatable herbaceous species for the livestock and unequivocally reduced tick population which play a role in reducing cattle milk production through closing off teats. The management of bush encroachment, if sustained, will contribute in stabilizing rangelands and help minimize the negative effects of feed and food crises in the future.

show abstract

“…For example, overstory composition affects soil litter accumulation (Maltez-Mouro et al 2005), as tree functional characteristics determine the production and decomposability of their litter (Pérez-Harguindeguy et al 2000). Litter, in turn, generally reduces species richness in temperate and Mediterranean forests (Borchsenius et al 2004;Casado et al 2004), and it modulates community composition through distinct species responses to its accumulation in the soil (Sydes and Grime 1981;Facelli and Pickett 1991). Thus, the variation in the relative proportion of certain trees within mixed forests sometimes alters the composition and richness of species in the understory (Beatty 1984;Crozier and Boerner 1984;Berger and Puettmann 2000;Jobidon et al 2004;Maltez-Mouro et al 2005; but see Thomsen et al 2005).…”

Section: Introductionmentioning

confidence: 95%

Small-scale variation of vegetation in a mixed forest understorey is partly controlled by the effect of overstory composition on litter accumulation

Rodríguez‐Calcerrada¹,

Nanos

Rey³

et al. 2011

Journal of Forest Research

View full text Add to dashboard Cite

We investigated how richness and composition of vascular plant species in the understory of a mixed hardwood forest stand varied with respect to the abundance and composition of the overstory. The stand is in central Spain and represents the southernmost range of distribution of several tree and herbaceous species in Europe. Understory species were identified in 46 quadrats (0.25 m 2 ) where variables litter depth and light availability were measured. In addition, we estimated tree density, basal area, and percent basal area by tree species within 6-mradius areas around each plot. Species richness and composition were studied using path analysis and scaledependent geostatistical methods, respectively. We found that the relative abundance of certain trees species in the overstory was more important than total overstory abundance in explaining understory species richness. Richness decreased as soil litter depth increased, and soil litter increased as the relative proportion of Fagus sylvatica in the overstory increased, which accounted for a negative, indirect effect of Fagus sylvatica on richness. Regarding understory species composition, we found that some species distributed preferentially below certain tree species. For example, Melica uniflora was most frequent below Fagus sylvatica and Quercus petraea while the increasing proportion of Q. pyrenaica in the overstory favored the presence of Cruciata glabra, Arenaria montana, Prunus avium, Conopodium bourgaei, Holcus mollis, Stellaria media and Galium aparine in the understory. Overall, these results emphasize the importance of individual tree species in controlling the assemblage and richness of understory species in mixed stands. We conclude that soil litter accumulation is one way through which overstory composition shapes the understory community.

show abstract

Herbaceous plant richness and vegetation cover in Mediterranean grasslands and shrublands

Cited by 53 publications

References 47 publications

Understory woody vegetation in manmade Mediterranean pine forests: variation in community structure along a rainfall gradient

Understory woody vegetation in manmade Mediterranean pine forests: variation in community structure along a rainfall gradient

Control of bush encroachment in Borana zone of southern Ethiopia: effects of different control techniques on rangeland vegetation and tick populations

Small-scale variation of vegetation in a mixed forest understorey is partly controlled by the effect of overstory composition on litter accumulation

Contact Info

Product

Resources

About