Comparing the role of site disturbance and landscape properties on understory species richness in fragmented periurban Mediterranean forests

Guirado M., Pino J., Rodà F. (2007) Comparing the role of site disturbance and landscape properties on understory species richness in fragmented periurban Mediterranean forests. Landscape Ecology. 22: 117-129.
Link
Doi: 10.1007/s10980-006-9009-y

Abstract:

We hypothesized that the spatial configuration and dynamics of periurban forest patches in Barcelona (NE of Spain) played a minor role in determining plant species richness and assemblage compared to site conditions, and particularly to both direct (measured at plot level) and potential (inferred from landscape metrics) human-associated site disturbance. The presence of all understory vascular plants was recorded on 252 plots of 100 m2 randomly selected within forest patches ranging in size from 0.25 ha to 218 ha. Species were divided into 6 groups, according to their ecology and conservation status. Site condition was assessed at plot level and included physical attributes, human-induced disturbance and Quercus spp. tree cover. Landscape structure and dynamics were assessed from patch metrics and patch history. We also calculated a set of landscape metrics related to potential human accessibility to forests. Results of multiple linear regressions indicated that the variance explained for non-forest species groups was higher than for forest species richness. Most of the main correlates corresponded to site disturbance variables related to direct human alteration, or to landscape variables associated to indirect human effects on forests: Quercus tree cover (a proxy for successional status) was the most important correlate of non-forest species richness, which decreased when Quercus tree cover increased. Human-induced disturbance was an important correlate of synanthropic and total species richness, which were higher in recently managed and in highly frequented forests. Potential human accessibility also affected the richness of most species groups. In contrast, patch size, patch shape and connectivity played a minor role, as did patch history. We conclude that human influence on species richness in periurban forests takes place on a small scale, whereas large-scale effects attributable to landscape structure and fragmentation are comparatively less important. Implications of these results for the conservation of plant species in periurban forests are discussed. © 2007 Springer Science + Business Media B.V.

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Efecto de la compresión wavelet de imágenes en su fotointerpretación.

Zabala A, Modugno S, Pons X, Buriel JA, Pino J (2007) Efecto de la compresión wavelet de imágenes en su fotointerpretación. Actes de la 7ª Semana Geomática. Edició en CD-ROM. Dipòsit legal: B-9432-2007

Quercus and Pinus cover are determined by landscape structure and dynamics in peri-urban Mediterranean forest patches.

Guirado M, Pino J, Rodà F (2007) Quercus and Pinus cover are determined by landscape structure and dynamics in peri-urban Mediterranean forest patches. Plant Ecology (doi 10.1007/s11258-007-9278-9)

A Land Suitability Index for Strategic Environmental Assessment in metropolitan areas

Marull J., Pino J., Mallarach J.M., Cordobilla M.J. (2007) A Land Suitability Index for Strategic Environmental Assessment in metropolitan areas. Landscape and Urban Planning. 81: 200-212.
Link
Doi: 10.1016/j.landurbplan.2006.11.005

Abstract:

This paper presents the Land Suitability Index (LSI), a transparent, modular hierarchical system of cartographic indices aimed at delivering Strategic Environmental Assessment (SEA) of developmental land uses for regional planning (European Directive 2001/42/EC). The LSI evaluates land suitability by combining three main sub-indices concerning (i) the vulnerability of the biosphere, lithosphere, and hydrosphere to impacts arising from implementing development proposals; (ii) the natural heritage value of the target area; and (iii) its contribution to terrestrial ecological connectivity. We have used the LSI to evaluate the impact of municipal urban plans in the Barcelona Metropolitan Region (BMR). For this case study, we provide redundancy and sensitivity analyses, and a partial validation using independent studies. Results showed noticeable inconsistencies between the municipal plans and the values of the LSI and its main sub-indices. There was moderate redundancy between sub-indices but considerable sensitivity to changes in input variables. Validation showed a high degree of coincidence with previous, independent, studies as regards connectivity. The quantitative and cartographic approach adopted by the methodology facilitates conveying the results to planners and policy makers. In addition, successive iterations to check the impact related to different alternative planning scenarios can be quickly performed. We therefore propose its application to other metropolitan areas. © 2006 Elsevier B.V. All rights reserved.

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Population biology of Kosteletzkya pentacarpos (Malvaceae) in the Llobregat delta (Catalonia, NE of Spain)

Pino J., De Roa E. (2007) Population biology of Kosteletzkya pentacarpos (Malvaceae) in the Llobregat delta (Catalonia, NE of Spain). Plant Ecology. 188: 1-16.
Link
Doi: 10.1007/s11258-006-9143-2

Abstract:

Field experiments and wild population monitoring have been performed to study the population biology of the rare long-lived Kosteletzkya pentacarpos (Malvaceae) in the Llobregat delta (Catalonia, NE Spain). Field experiments explored the fate of seeds in soil at different depths, seedling emergence, and seedling survival, growth and flowering with and without canopy cover during the first 2 years of life. They also were used to ascertain the size-related pattern of seedling survivorship and flowering. Field data concerning mortality, growth and fecundity of adult plants were collected yearly in three wild populations for 7-9 years. In old adults (reproducing long before the beginning of the study), ANOVAR tests were performed to compare maximum diameter, total and fertile shoots, and viable seeds per plant between years and populations. New adults (starting flowering the first year of study or in subsequent years) were used to explore, using linear and polynomial regressions, the association of RGR and both total and fertile shoot production with (i) plant size (maximum basal diameter or its logarithm); (ii) plant age (years in adult stage); and (iii) plant age after removing the effect of size and year-to-year fluctuations. In this case, we examined the age-related pattern of the residuals obtained from the regressions with size and year. The study identified the following main demographic features of K. pentacarpos: (i) transient, shallow soil seed bank; (ii) shade tolerance of seedling emergence; (iii) canopy-facilitation of seedling survival and bolting during the first two years of life; (iv) size-related pattern for seedling survivorship but not flowering; (v) exclusive dependence on a fluctuating seed output for reproduction; (vi) rapid adult growth; and (vii) high adult longevity but (viii) rapid depletion of fecundity with age. Seed output was highly constrained by mining insects. The changing size-structure and the decreasing reproductive success of old adults in several populations suggest that K. pentacarpos might undergo a dynamics of population establishment and extinction in the Ricarda marshes. Because of fluctuating reproduction and the lack of a persistent seed bank, the conservation of standing adult populations appears to be a key factor to ensure the persistence of the species. © 2006 Springer Science+Business Media B.V.

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Population dynamics of the rare plant Kosteletzkya pentacarpos (Malvaceae): A nine-year study

Pino J., Picó F.X., De Roa E. (2007) Population dynamics of the rare plant Kosteletzkya pentacarpos (Malvaceae): A nine-year study. Botanical Journal of the Linnean Society. 153: 455-462.
Link
Doi: 10.1111/j.1095-8339.2007.00628.x

Abstract:

Rare plant species have extremely narrow distributions that can be reduced to a single or few populations. The rare long-lived plant Kosteletzkya pentacarpos is one such species because only two extant localities are known in the western Mediterranean. In this study, we analyse the population dynamics over nine years of the only population known in north-east Spain, which is located at the Llobregat delta (Barcelona). We collected basic demographic data to build a transition matrix model. We computed population growth rates λ and their confidence intervals for each year of study. We conducted elasticity and variance decomposition analyses to determine the relative importance of vital rates to overall population dynamics. On average, the K. pentacarpos population exhibited an increasing dynamics. Survivorship of adult plants contributed the most to each λ, whereas temporal variance in fecundity and juvenile fate explained the observed variation in λ. Despite the increasing dynamics of K. pentacarpos, important reductions in fecundity resulting from biotic agents and recruitment owing to habitat limitations are constraints for population growth. We conclude that the knowledge generated in this long-term study should be used to create new K. pentacarpos populations at the Llobregat delta in order to minimize the risk of extinction following catastrophic events that are nearly impossible to predict. © 2007 The Linnean Society of London.

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Regional assessment of plant invasions across different habitat types

Vilà M., Pino J., Font X. (2007) Regional assessment of plant invasions across different habitat types. Journal of Vegetation Science. 18: 35-42.
Link
Doi: 10.1658/1100-9233(2007)18[35:RAOPIA]2.0.CO;2

Abstract:

Questions: 1. Which habitats have the highest degree of invasion? 2. Do native species-rich communities have also a high degree of invasion? 3. Do the patterns of association between native and alien species richness vary between habitats. Location: Catalonia region (NE Spain). Methods: We conducted a large regional analysis of 15 655 phytosociological relevés to detect differences in the degree of invasion between European Nature Information System (EUNIS) habitats representative of temperate and Mediterranean European areas. Results: Alien species were present in less than 17 % of the relevés and represented less than 2% of the total number of species per habitat. The EUNIS habitats with the highest alien species richness were arable land and gardens followed by anthropogenic forb-rich habitats, riverine and lakeshore scrubs, southern riparian galleries and thickets and trampled areas. In contrast, the following habitats had never any alien species: surface running waters, raised and blanket bogs, valley mires, poor fens and transition mires, base-rich fens, alpine and sub-alpine grasslands, sub-alpine moist or wet tall-herb and fern habitats, alpine and sub-alpine scrub habitats and spiny Mediterranean heaths. There was a unimodal relationship between the mean native and mean alien species richness per EUNIS habitat with a high number of aliens in habitats with intermediate number of native species and a low number of aliens at both extremes of the native species gradient. Within EUNIS habitats, the relationship was positive, negative or non-significant depending on the habitat type without any clear pattern related to the number of native species. Alien species richness was not related to plot size, neither between habitats nor within habitats. Conclusions: The analysis emphasised that the habitats with a higher degree of invasion were the most disturbed ones and that in general habitats rich in native species did not harbour less invaders than habitats poor in native species. © IAVS; Opulus Press.

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Understorey plant species richness and composition in metropolitan forest archipelagos: Effects of forest size, adjacent land use and distance to the edge

Guirado M., Pino J., Rodà F. (2006) Understorey plant species richness and composition in metropolitan forest archipelagos: Effects of forest size, adjacent land use and distance to the edge. Global Ecology and Biogeography. 15: 50-62.
Link
Doi: 10.1111/j.1466-822X.2006.00197.x

Abstract:

Aim: To address the relative role of adjacent land use, distance to forest edge, forest size and their interactions on understorey plant species richness and composition in perimetropolitan forests. Location: The metropolitan area of Barcelona, north-eastern Spain. Methods: Twenty sampling sites were distributed in two forest size-categories: small forest patches (8-90 ha) and large forest areas (> 18,000 ha). For each forest-size category, five sites were placed adjacent to crops and five sites adjacent to urban areas. Vascular plant species were recorded and human frequentation was scored visually in 210 10 ×10 m plots placed at 10, 50 and 100 m from the forest edge, and additionally at 500 m in large forest areas. Plant species were grouped according to their ecology and rarity categories. A nonmetric multidimensional scaling (NMS) ordination was carried out to detect patterns of variation in species assemblage, and to explore the relationships between these patterns and the richness of the species groups and the studied factors. Factorial ANOVAS were used to test the significance of the studied factors on the richness of species groups. Relationships between human frequentation and the studied variables were assessed through contingency tables. Results: Forest-size category was the main factor affecting synanthropic species (i.e. those thriving in man-made or man-disturbed habitats). Synanthropic species richness decreased with increasing distance from the forest edge and, when forests were adjacent to crops, it was higher in small forest patches than in large forest areas. Richness of rare forest species was lower in small forest patches than in large forest areas when forests were adjacent to urban areas. Richness of common forest species and of all forest species together were higher close to the forest edge than far from it when forests were adjacent to urban areas. Forests adjacent to urban areas were more likely to experience high human frequentation, particularly in those plots nearest to the forest edge. Main conclusions: Forest-size category and adjacent land use were the most important factors determining species richness and composition. The preservation of large forests adjacent to crops in peri-urban areas is recommended, because they are less frequented by humans, are better buffered against the percolation of nonforest species and could favour the persistence of rare forest species. © 2006 Blackwell Publishing Ltd.

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Land Cover Changes in Europe from the 50’ies.

Gerard F, Olschofsky K, Köhler R, Mücher S, Hazeu G, Pino J, Luque S, Halada L, Bugar G, Gregor M (2006) Land Cover Changes in Europe from the 50’ies. University of Hamburg. ISBN: 80-89088-46-5.

A land suitability index for strategic environmental assessment in metropolitan areas.

Marull J, Pino J, Mallarach JM, Cordobilla MJ (2006) A land suitability index for strategic environmental assessment in metropolitan areas. Landscape and Urban Planning 81: 200-212 DOI:10.1016/j.landurbplan.2006.11.005

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