Carolina Martínez-Ruiz

The influence of aspect on the early growth dynamics of hydroseeded species in coal reclamation areas

ABSTRACT Question: Does aspect affect hydroseeding success and the development of vegetation during early vegetation establishment on the steep slopes of coal wastes during the reclamation process? Location: Open-pit coal mine near Villanueva de la Peña, northern Spain. Methods: In the first year after hydroseeding, we monitored the dynamics of hydroseeded species in three permanent plots of 20 m2 on north- and south-facing slopes every two months. Soil properties and weather conditions were also monitored. Results: Aspect was related to total plant cover during early revegetation, and south-facing slopes had the lowest cover. Aspect also influenced the early dynamics of hydroseeded grasses and legumes establishing on these slopes. Grass cover was greater on the north slope throughout the study, but differences in plant cover between north and south slopes appeared later for the legumes. Aspect also affected the relative contribution of both of grasses and legumes to the total plant cover, with grasses dominant on both northern and southern slopes, except during the summer on the southern slope. The species with the greatest difference in cover between the north- and south-facing slopes were Festuca spp., Lolium perenne and Trifolium repens. Conclusion: In coal mine reclamation areas of Mediterranean climates, differences in the development of hydroseeded species depended on the slope of the coal mine reclamation areas, and this information is of importance to managers in selecting species for use in reclamation. Nomenclature: Tutin et al. (1964–1980).

Vulnerabilidad de los bosques naturales en el Chocó biogeográfico colombiano: actividad minera y conservación de la biodiversidad

El Choco es una region con alta biodiversidad e impactada por la mineria de oro y platino. En este trabajo se determino la vulnerabilidad potencial de los bosques del Choco para la perdida de especies vegetales debido a la actividad minera. En distintos municipios mineros del territorio chocoano se documentaron las tecnicas de extraccion de minerales y la percepcion de los mineros sobre la mineria en sus territorios. A partir de datos de produccion de oro y platino (1990-2012), titulos mineros (2012-2013) y numero de minas y maquinaria usada (2008-2012) se propusieron los indices de actividad minera (IAMAR) y de produccion minera relativa (IPMAR) en todos los entes territoriales del Choco; ambos indices se aplican en este estudio por primera vez. Ademas se cuantifico el numero de especies de distribucion restringida y el numero de especies amenazadas como factores de vulnerabilidad. Con esas cuatro variables se determino el indice de vulnerabilidad floristica potencial para la perdida de especies (IVFP), que vario significativamente entre municipios y subregiones del territorio chocoano. Los municipios con mayor IVFP fueron Condoto (9,43 %), Istmina (7,75 %), Novita (7,74 %), Quibdo (7,64 %) y San Jose del Palmar (6,56 %). A nivel subregional, el San Juan (54,8 %) presento el mayor IVFP. La mineria en el Choco amenaza ecosistemas estrategicos de importancia mundial para la conservacion de la biodiversidad, lo que hace necesario establecer medidas para prevenir y mitigar la perdida de especies en territorios con alta vulnerabilidad debido a la actividad minera.

Effects of short-term grazing exclusion on vegetation and soil in early succession of a Subhumid Mediterranean reclaimed coal mine

AimsTo assess the short-term effect of herbivory exclusion on vegetation and soil and to relate differences in floristic composition to changes in soil properties in a reclaimed coal mine in northern Spain.MethodsTwo adjacent main plots of 50 × 50 m, one fenced to prevent ungulates grazing and the other not, were established in a north-facing slope to analyze differences in the soil and plant community in the short time.ResultsA clear influence of grazing exclusion on soil properties and plant community composition and structure was found but no influence on species diversity. However, only three soil parameters (organic matter, K, and Mg, with higher values in the ungrazed community) were related to the differences in floristic composition. Species responses to the soil gradient from ungrazed to grazed areas were also related to their particular life-history traits. No trend in the dispersal-mode replacement was found.ConclussionHerbivores could be a key factor preventing revegetation at early stages of succession in the study area, although they could play a key role as efficient seed dispersers, particularly of endozoochorous legume species, and controlling the expansion of dominant introduced species.

Can native shrubs facilitate the early establishment of contrasted co-occurring oaks in Mediterranean grazed areas?

Questions Can shrubs (Cytisus multiflorus) and large herbivore exclusion (fence) facilitate seedling survival and growth of marcescent and sclerophyllous oaks (Quercus pyrenaica vs Q. ilex subsp. ballota) under a bioclimatic limit in Mediterranean grazed areas? Location Open oak woodlands in central-western Spain (41o13’ N, 6o24’ W). Methods A two-year field experiment was conducted by planting 200 seedlings of each Quercus species under four different treatments combining the influence of nurse shrubs and fencing on Quercus seedling survival and growth. Results C. multiflorus enhanced the poor Quercus seedling survival found in the study area, at least during the first two years after planting and particularly during the first dry season. The improvement in soil organic matter under shrub canopy may have contributed to this positive effect, which was more pronounced on Q. pyrenaica seedlings. Seedling herbivory did not seem to be a limitation to survival. Increase seedling growth in both species was also very low and no growth was recorded two years after planting without shrubs. The positive shrub effect on seedling growth, especially marked in fenced areas, was more important in Q. pyrenaica in the first growing period and in Q. ilex in the second; two years after planting no different shrub effect on growth was found in either Quercus species. Seedling herbivory was a limitation to seedling growth in areas without shrubs, mainly in the case of Q. pyrenaica. Conclusions In Mediterranean grazed areas with important summer drougth and very sandy soils, shrubby Cytisus multiflorus plants have a clear facilitative effect on seedlings of ecologically-contrasted Quercus species. The facilitative effect was found in both marcescent and sclerophyllous oak seedlings, but to a different degree depending on the species considered and the variable measured (survival or growth). In terms of survival, the marcescent species was more favored by shrub cover than the sclerophyllous one, and this effect was accentuated throughout time. However, in terms of growth, although Q. pyrenaica was initially more favored by shrubs, differences between both species were attenuated after two years. Therefore, C. multiflorus can have a key role in the restoration of these oak degraded environments. This article is protected by copyright. All rights reserved.

Mapping forest vegetation patterns in an Atlantic–Mediterranean transitional area by integration of ordination and geostatistical techniques

Aims Forest vegetation variability may be explained by the complex interplay among several spatial structuring factors, including climate and topography. We modelled the spatial variability of forest vegetation assemblages and significant environmental variables along a complex environmental gradient or coenocline to produce a detailed cartographic database portraying the distribution of forests along it. Methods We combined an analysis of ordination coenoclines with kriging over 772 field data plots from the third Spanish National Forest Inventory in an Atlantic–Mediterranean transitional area (northern Spain). Important Findings The best fitted empirical semivariogram revealed a strong spatial structure of forest species composition along the complex environmental gradient considered (the climatic–topographic gradient from north to south). The steady and gradual increase of semivariance with a marked lag distance indicates a gradual turnover of forest assemblages according to the climatic–topographic variations (regional or local). Two changes in the slope of the semivariogram suggest the existence of two different scales of spatial variation. The interpolation map by Kriging of forest vegetation assemblages along the main coenocline shows a clear spatial distribution pattern of trees and shrubs in accordance with the spatial variation of significant environmental variables. We concluded that the multivariate geostatistical approach is a suitable technique for spatial analysis of forest systems employing data from national forest inventories based on a regular network of field plots. The development of an assortment of maps describing changes in vegetation assemblages and variation in environmental variables is expected to be a suitable tool for an integrated forest management and planning.