Response of vegetation to exclusion and grazing in Mediterranean wet mountain pastures (Sierra Nevada, Granada, Spain)

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GONZÁLEZ-REBOLLAR 1 1 Group of Grassland and Mediterranean

1 Response of vegetation to exclusion and grazing in Mediterranean wet mountain pastures (Sierra Nevada, Granada, Spain) A.B. ROBLES 1, M.E. RAMOS 1, C. SALAZAR 2, J.L. GONZÁLEZ-REBOLLAR 1 1 Group of Grassland and Mediterranean Silvopastoral Systems Estación Experimental del Zaidín (CSIC) 2 Dpt. of Animal Biology, Vegetal Biology and Ecology. University of Jaén anabelen.robles@eez.csic.es CIHEAM IAM ZARAGOZA

INTRODUCTION PROJECT: Extensive Livestock and Biodiversity (Regional Government of Andalusia/ Spanish Council for Scientific Research-CSIC ) (2008-2014) Assess the role of livestock in the

2 INTRODUCTION PROJECT: Extensive Livestock and Biodiversity (Regional Government of Andalusia/ Spanish Council for Scientific Research-CSIC ) ( ) Assess the role of livestock in the conservation of plant species and communities of Mediterranean forest. Under the project: We have studied: endangered species and/or plant communities present in in the Red Nature 2000 (some are priority habitats). We have selected Wet mountain pastures. These are of great importance for livestock feeding during summer in the semiarid Mediterranean region. This climate determines many traditional livestock management practices ºC J F M A M J J A S O N D ubc Montero de Burgos and J.L. González-Rebollar (1975)

3 INTRODUCTION Nowadays, mountain areas have suffered remarkable changes in land use: Traditional practices are disappearing, such as: Transhumance Irrigation ditches built by man to create pastures ( acequias de careo ) In sum: Biodiversity declines (This concerns : endangered livestock and flora) In this paper: We have studied wet mountain pastures: dominated by Nardus stricta (6230 HIC*) in Sierra Nevada National Park (Southern Spain). The origin of pastures: Snow melting Irrigation ditches built by man ( acequias careo ).

INTRODUCTION Objective In this context, This work aims

on two types of wet pastures in the Sierra Nevada

species richness, diversity, and species composition

4 INTRODUCTION Objective In this context, This work aims to determine the effect of midterm livestock exclosure on two types of wet pastures in the Sierra Nevada National Park: 1), dominated by Carex nigra (L.) Reichard and Nardus stricta L., and 2) Fescue Pastures dominated by Festuca iberica (Hack.) K. Richt. We compared the changes in biomass, plant cover, species richness, diversity, and species composition after 6 years (2008 vs 2014) in: grazed and non- grazed areas Study Area Sierra Nevada N.P. Granada Aldeire Spain m.a.s.l 530 mm

Sheep: 620 (2008) and 550 (2014) Cattle: 50 to 70 heads.

stricta Fescue Pasture (FP): F. iberica and N.

Sampling and Design 20 Plots (3 x3): 10 B/10 FP In each type of pasture 5 plots 5

methods 2 m-long Transects (2 transects) 50 points/transect (Total: 100

Biodiversity: Shannon Index (log2) Floristic composition: i) grasses, ii) legumes,

5 MATERIALS and METHODS 1. Monitoring Year: 2008 and 2014 (485/518 mm ) Sampling Season: July Livestock: Sheep: 620 (2008) and 550 (2014) Cattle: 50 to 70 heads. Types of wet mountain pastures: (B): C. nigra and N. stricta Fescue Pasture (FP): F. iberica and N.stricta (low cover) Grazing Treatments: Non-grazed Plots Plot Non- 2. Sampling and Design 20 Plots (3 x3): 10 B/10 FP In each type of pasture 5 plots 5 Non-grazed plots Parameters: Above-ground biomass: 8 quadrats/plots Point-Quadrat methods 2 m-long Transects (2 transects) 50 points/transect (Total: 100 point/plot) Data from this procedure: Plant cover Richness of species Biodiversity: Shannon Index (log2) Floristic composition: i) grasses, ii) legumes, iii) tall and iv) small graminoids Statistical Analyses Two-way repeated measures ANOVA procedure of SPSS/ GLM: Where: Years: 2008 and 2014 as within-subject factor (repeat factor) Treatment: nongrazed and grazed as between-subject factor, and Factor block is the random effect.

Non-grazed Non-grazed Cover plant (%), g DM m -2 year -1 Non-grazed Non-grazed RESULTS AND DISCUSSION g DM m -2 year -1 g DM

Non-grazed Non-grazed Non-grazed Non-grazed 2008 Biomass production 2014 ANOVA (p-valor) 2008 2014 Treatment <0.001 <0.

026 Biomass: > In both pastures: 2014 > 2008 Rain fall : 518 vs 485 mm Sheep: 550 vs 620 animals Non-grazed > Plant cover

6 Non-grazed Non-grazed Cover plant (%), g DM m -2 year -1 Non-grazed Non-grazed RESULTS AND DISCUSSION g DM m -2 year -1 g DM m -2 year Non-grazed Non-grazed Non-grazed Non-grazed 2008 Biomass production 2014 ANOVA (p-valor) Treatment <0.001 <0.001 Year <0.001 <0.001 Treatment*Year Biomass: > In both pastures: 2014 > 2008 Rain fall : 518 vs 485 mm Sheep: 550 vs 620 animals Non-grazed > Plant cover ANOVA (p-valor) Treatment Year Treatment*Year Both pastures are similar response: 2008 : Non-grazed > 2014: > Non- Although, the only significant difference is in (Treatment and interaction)

Richness of species and diversity had a similar response 2008 2014 ANOVA (p-valor) Festuce pasture Treatment 0.682 0.489 Year 0.779 0.128 Treatment*Year 0.

7 Richness (# spp.) Non-grazed Non-grazed 1200 RESULTS AND DISCUSSION 1000 g DM m -2 year Richness Non-grazed Non-grazed Richness of species and diversity had a similar response ANOVA (p-valor) Festuce pasture Treatment Year Treatment*Year After 6 year In both pastures: a slight downward trend can be observed in non-grazed plots: 2008 > But it is different in plots: : Increase : Decrease Although, no significant differences were found between treatments or year Statistical differences: only found in interactions in ( Treatment *Year)

8 RESULTS AND DISCUSSION (Plant cover %) Only significant differences were found: Botanical Composition Fun.groups/ Species N-grazed N-grazed Grasses 77.4 ± ± ± ±19.9 Small gramoids 9.4 ± ± ± ±5.2 Tall graminoids 11.4 ± ± ± ±2.4 Legumes 20.0 ± ± ± ±3.9 F. iberica 12.2 ± ± ± ±4.9 N. stricta 59.6 ± ± ± ±20.0 Fescue Pastures (Plant cover %) Fun.groups/ Species N-grazed N-grazed Grasses ± ± ± ±2.2 Small gramoids 1.4 ± ± ± ±8.0 Tall graminoids 10.4 ± ± ± ±3.4 Legumes 63.6 ± ± ±0.9 62±8.5 F. iberica 80.4 ±8.3 64± ± ±8.9 N. stricta 33.4 ± ± ± ±9.4 ANOVA (p-valor ) Treatment Year N. stricta F. iberica Grasses Legumes Treatment* Year After six years No significant differences were found between treatment or year for functional groups or species. Only: Exclosure was: Positive: Tall graminoids Negative: Festuca iberica Small graminoids Legumes ANOVA Treatment Year (p-valor ) *Year Tall graminoids F. iberica Small gramoids Legumes After six years Exclosure was: Positive: Nardus stricta Negative: F. iberica Legumes Grasses: Non-grazed > Legumes: Different response between treatments within each year

9 CONCLUSIONS Biomass production is the parameter which best reflects the effect of the treatment and year: Greater in the Non-grazed plots and in 2014 Moreover, the fescue pasture was more productive than the borreguil. Furthermore a slight downward trend can be observed in plant cover, richness and diversity of species in non-grazed plots. Regarding the floristic composition it seems that exclosures have : a negative effect on: F. iberica, legumes and small graminoids (the later only in borreguil ) on the contrary they favour grasses and, precisely, N. stricta in fescue pasture Nevertheless, our results indicate that after 6 years of pasture exclusions few differences between grazed and not grazed plots were found, except in biomass production

A. Bernués, J.L. Riedel, M.A. Asensio, M. Blanco, A. Sanz, R. Revilla, I. I. Casasús

LNCS2.4 An integrated approach to study the role of grazing farming systems in the conservation of rangelands in a protected natural park (Sierra de Guara, Spain) A. Bernués, J.L. Riedel, M.A. Asensio,