The main objective of this dissertation was to assess whether cultivated area in Iraq, as estimated using satellite remote sensing, changed during and as a result of war and sanctions. The first study used MODIS NDVI data during OIF and the end of UN sanctions to study changes in cultivated area for Iraq as a whole and to identify spatial patterns. The results revealed significant changes in cultivated area for Iraq as a whole, with cultivated area decreasing over 35,000 ha per year. Regionally, there was little change in cultivated area in northern governorates in the Kurdish Autonomous Region, significant decreases in governorates in central Iraq, and initial increases in governorates containing the southern marshlands followed by decreases related to drought. The second study used Landsat images converted to NDVI to study changes in cultivated area in central Iraq for four periods of conflict, and relates those changes to effects on food security. The results indicated that cultivated area changed little between the Iran-Iraq War (1980 to 1988) and the Gulf War (1990 to 1991), increased by 20 percent (from 1.72 to 2.04 Mha) during the period of United Nations sanctions (1990 to 2003), and dropped to below pre-sanction levels (1.40 Mha) during Operation Iraqi Freedom (2003 to 2011). Finally, the third study builds on findings from the second study to address patterns of agricultural land abandonment in central Iraq. The largest areas of abandoned land were those cultivated during the Late Sanctions period (2000-2003). Further, the results indicate that proximity to surface water and roads are strong indicators of continuity of agricultural land use, and that abandoned lands are positioned in peripheral regions more distant from surface water and the transportation grid. We also found that surface soil salinity is increasing in the cultivated lands of central Iraq, regardless of whether it was cultivated during every period or during only a single period. The overall findings indicate that the UN sanctions had the greatest impact on cultivated area, which increased during sanctions, when food imports all but ceased, and then decreased after sanctions ended and food imports resumed. / Ph. D.

The conversion of native forests to pastures and crops is one of the most extensive causes of deforestation worldwide. Concomitant with agricultural landscape modification are the processes of habitat loss and fragmentation, which are major causes of species’ extinctions, population declines and altered ecosystem functions. However, in many tropical, sub-tropical and temperate regions, abandoned agricultural lands are reverting to regrowth or secondary forest, which represents an important opportunity for passive landscape restoration. Regrowth may be particularly important in highly modified landscapes, where the area of mature forest may be insufficient to support viable plant and animal communities without some form of restoration. Some studies of fauna populations in regrowth forest have found recovery of species richness within several decades, although recovery of species composition may take at least 100 years and some species may be permanently lost. While these findings are encouraging, they generally fail to account for the landscape context in which regrowth occurs and focus mainly on tropical forests. The aim of this thesis was to advance the understanding of fauna recovery in regrowth forests on abandoned agricultural land by: i) comparing woodland bird communities in a replicated chronosequence of semi-arid sub-tropical regrowth forests; and ii) quantifying how the ecological values of regrowth habitat vary among stand-, patch- and landscape-levels of ecological organisation. A review of 68 studies of fauna recovery in regrowth forests, revealed that current knowledge is limited by the predominance of studies conducted: in tropical rainforests; with minimal replication of sites; in landscapes within proximity of large tracts of relatively undisturbed mature forests; and with limited consideration of the influence of the spatial context on fauna recovery in regrowth forest. This study makes a significant contribution to understanding fauna recovery in regrowth forests by quantifying the recovery of estimated bird species richness to levels similar to mature forest, within a period of 30-60 years, in highly modified semi-arid agricultural landscapes in sub-tropical Australia. An ordination of the similarity in species composition among forest types also suggested that after 30-60 years regrowth bird communities are more similar to mature brigalow forest than the younger regrowth. This is important for the recovery of brigalow ecosystems, an endangered ecological community where regrowth is currently given minimal protection from further clearing. Comparisons of the importance of habitat attributes using model averaging and hierarchical partitioning of generalised linear models of the species richness of woodland birds showed that bird species richness was positively associated with patch age, and that stand-level factors such as grazing disturbance and the abundance of mistletoes (Amyema spp.) were also important. The spatial context of vegetation patches (size, shape and isolation) was equally important for bird species richness, with more species of woodland dependent, nectar/frugivores and non-ground foraging insectivores occurring in less modified landscape contexts, and the converse for generalist species, ground foraging insectivores and granivores. While a number of woodland dependent bird species known to be in decline in temperate woodlands of southern Australia were absent or rare in regrowth forests, several species (e.g., eastern yellow robin) also occupied regrowth habitats. This finding suggests that these more sensitive species may respond positively to landscape restoration through targeted retention of brigalow regrowth. The landscape-level amount of forest varied in importance among regrowth age classes and bird groups. In general, the amount and number of mature forest patches in the landscape were of lower importance than local attributes. However, the amount of mature forest and old regrowth (> 30 years) in the landscape did have an important positive influence on the number of woodland bird species and species’ abundance; suggesting that regrowth is making an important contribution to landscape recovery in the study area. Mistletoe abundance was strongly dependent on particular species of frugivores for seed dispersal (e.g., mistletoebird, spiny-cheeked honeyeater and painted honeyeater), and varied considerably among three sub-regions of the study area. In general, mistletoe abundance increased in linear patches and more highly modified landscapes but was also dependent on the abundance of seed dispersers and brigalow stand condition. These findings suggest that narrow linear patches in brigalow landscapes can have important conservation values for woodland birds. The study outcomes have important implications for research and management of regrowth vegetation, both within Australia and internationally. From an international perspective, the study highlights the need for greater consideration of the importance of regrowth forest in a landscape context for conserving and restoring fauna communities. From an Australian perspective, the study provides important baseline information for the conservation and management of woodland bird habitat in fragmented brigalow landscapes. Prior to this research, very little was known on the spatial ecology of woodland birds in the region. The study highlights the important conservation values of small and often linear mature brigalow patches for woodland birds and the considerable potential for restoration of habitat for a diverse range of species through the retention of regrowth vegetation. In particular, the research outcomes suggest that targeting the retention of regrowth towards increasing the size and reducing the isolation of mature brigalow forests may be an effective strategy to maximise biodiversity benefits. Brigalow regrowth stands will need to be retained for at least 60 years and probably longer to maintain viable woodland bird communities. For this to happen on a regional-scale, brigalow regrowth needs to be given greater recognition for potential biodiversity benefits either within a legislative framework or by incentive schemes to promote the long term persistence of regrowth habitat within the landscape.

The conversion of native forests to pastures and crops is one of the most extensive causes of deforestation worldwide. Concomitant with agricultural landscape modification are the processes of habitat loss and fragmentation, which are major causes of species’ extinctions, population declines and altered ecosystem functions. However, in many tropical, sub-tropical and temperate regions, abandoned agricultural lands are reverting to regrowth or secondary forest, which represents an important opportunity for passive landscape restoration. Regrowth may be particularly important in highly modified landscapes, where the area of mature forest may be insufficient to support viable plant and animal communities without some form of restoration. Some studies of fauna populations in regrowth forest have found recovery of species richness within several decades, although recovery of species composition may take at least 100 years and some species may be permanently lost. While these findings are encouraging, they generally fail to account for the landscape context in which regrowth occurs and focus mainly on tropical forests. The aim of this thesis was to advance the understanding of fauna recovery in regrowth forests on abandoned agricultural land by: i) comparing woodland bird communities in a replicated chronosequence of semi-arid sub-tropical regrowth forests; and ii) quantifying how the ecological values of regrowth habitat vary among stand-, patch- and landscape-levels of ecological organisation. A review of 68 studies of fauna recovery in regrowth forests, revealed that current knowledge is limited by the predominance of studies conducted: in tropical rainforests; with minimal replication of sites; in landscapes within proximity of large tracts of relatively undisturbed mature forests; and with limited consideration of the influence of the spatial context on fauna recovery in regrowth forest. This study makes a significant contribution to understanding fauna recovery in regrowth forests by quantifying the recovery of estimated bird species richness to levels similar to mature forest, within a period of 30-60 years, in highly modified semi-arid agricultural landscapes in sub-tropical Australia. An ordination of the similarity in species composition among forest types also suggested that after 30-60 years regrowth bird communities are more similar to mature brigalow forest than the younger regrowth. This is important for the recovery of brigalow ecosystems, an endangered ecological community where regrowth is currently given minimal protection from further clearing. Comparisons of the importance of habitat attributes using model averaging and hierarchical partitioning of generalised linear models of the species richness of woodland birds showed that bird species richness was positively associated with patch age, and that stand-level factors such as grazing disturbance and the abundance of mistletoes (Amyema spp.) were also important. The spatial context of vegetation patches (size, shape and isolation) was equally important for bird species richness, with more species of woodland dependent, nectar/frugivores and non-ground foraging insectivores occurring in less modified landscape contexts, and the converse for generalist species, ground foraging insectivores and granivores. While a number of woodland dependent bird species known to be in decline in temperate woodlands of southern Australia were absent or rare in regrowth forests, several species (e.g., eastern yellow robin) also occupied regrowth habitats. This finding suggests that these more sensitive species may respond positively to landscape restoration through targeted retention of brigalow regrowth. The landscape-level amount of forest varied in importance among regrowth age classes and bird groups. In general, the amount and number of mature forest patches in the landscape were of lower importance than local attributes. However, the amount of mature forest and old regrowth (> 30 years) in the landscape did have an important positive influence on the number of woodland bird species and species’ abundance; suggesting that regrowth is making an important contribution to landscape recovery in the study area. Mistletoe abundance was strongly dependent on particular species of frugivores for seed dispersal (e.g., mistletoebird, spiny-cheeked honeyeater and painted honeyeater), and varied considerably among three sub-regions of the study area. In general, mistletoe abundance increased in linear patches and more highly modified landscapes but was also dependent on the abundance of seed dispersers and brigalow stand condition. These findings suggest that narrow linear patches in brigalow landscapes can have important conservation values for woodland birds. The study outcomes have important implications for research and management of regrowth vegetation, both within Australia and internationally. From an international perspective, the study highlights the need for greater consideration of the importance of regrowth forest in a landscape context for conserving and restoring fauna communities. From an Australian perspective, the study provides important baseline information for the conservation and management of woodland bird habitat in fragmented brigalow landscapes. Prior to this research, very little was known on the spatial ecology of woodland birds in the region. The study highlights the important conservation values of small and often linear mature brigalow patches for woodland birds and the considerable potential for restoration of habitat for a diverse range of species through the retention of regrowth vegetation. In particular, the research outcomes suggest that targeting the retention of regrowth towards increasing the size and reducing the isolation of mature brigalow forests may be an effective strategy to maximise biodiversity benefits. Brigalow regrowth stands will need to be retained for at least 60 years and probably longer to maintain viable woodland bird communities. For this to happen on a regional-scale, brigalow regrowth needs to be given greater recognition for potential biodiversity benefits either within a legislative framework or by incentive schemes to promote the long term persistence of regrowth habitat within the landscape.

The conversion of native forests to pastures and crops is one of the most extensive causes of deforestation worldwide. Concomitant with agricultural landscape modification are the processes of habitat loss and fragmentation, which are major causes of species’ extinctions, population declines and altered ecosystem functions. However, in many tropical, sub-tropical and temperate regions, abandoned agricultural lands are reverting to regrowth or secondary forest, which represents an important opportunity for passive landscape restoration. Regrowth may be particularly important in highly modified landscapes, where the area of mature forest may be insufficient to support viable plant and animal communities without some form of restoration. Some studies of fauna populations in regrowth forest have found recovery of species richness within several decades, although recovery of species composition may take at least 100 years and some species may be permanently lost. While these findings are encouraging, they generally fail to account for the landscape context in which regrowth occurs and focus mainly on tropical forests. The aim of this thesis was to advance the understanding of fauna recovery in regrowth forests on abandoned agricultural land by: i) comparing woodland bird communities in a replicated chronosequence of semi-arid sub-tropical regrowth forests; and ii) quantifying how the ecological values of regrowth habitat vary among stand-, patch- and landscape-levels of ecological organisation. A review of 68 studies of fauna recovery in regrowth forests, revealed that current knowledge is limited by the predominance of studies conducted: in tropical rainforests; with minimal replication of sites; in landscapes within proximity of large tracts of relatively undisturbed mature forests; and with limited consideration of the influence of the spatial context on fauna recovery in regrowth forest. This study makes a significant contribution to understanding fauna recovery in regrowth forests by quantifying the recovery of estimated bird species richness to levels similar to mature forest, within a period of 30-60 years, in highly modified semi-arid agricultural landscapes in sub-tropical Australia. An ordination of the similarity in species composition among forest types also suggested that after 30-60 years regrowth bird communities are more similar to mature brigalow forest than the younger regrowth. This is important for the recovery of brigalow ecosystems, an endangered ecological community where regrowth is currently given minimal protection from further clearing. Comparisons of the importance of habitat attributes using model averaging and hierarchical partitioning of generalised linear models of the species richness of woodland birds showed that bird species richness was positively associated with patch age, and that stand-level factors such as grazing disturbance and the abundance of mistletoes (Amyema spp.) were also important. The spatial context of vegetation patches (size, shape and isolation) was equally important for bird species richness, with more species of woodland dependent, nectar/frugivores and non-ground foraging insectivores occurring in less modified landscape contexts, and the converse for generalist species, ground foraging insectivores and granivores. While a number of woodland dependent bird species known to be in decline in temperate woodlands of southern Australia were absent or rare in regrowth forests, several species (e.g., eastern yellow robin) also occupied regrowth habitats. This finding suggests that these more sensitive species may respond positively to landscape restoration through targeted retention of brigalow regrowth. The landscape-level amount of forest varied in importance among regrowth age classes and bird groups. In general, the amount and number of mature forest patches in the landscape were of lower importance than local attributes. However, the amount of mature forest and old regrowth (> 30 years) in the landscape did have an important positive influence on the number of woodland bird species and species’ abundance; suggesting that regrowth is making an important contribution to landscape recovery in the study area. Mistletoe abundance was strongly dependent on particular species of frugivores for seed dispersal (e.g., mistletoebird, spiny-cheeked honeyeater and painted honeyeater), and varied considerably among three sub-regions of the study area. In general, mistletoe abundance increased in linear patches and more highly modified landscapes but was also dependent on the abundance of seed dispersers and brigalow stand condition. These findings suggest that narrow linear patches in brigalow landscapes can have important conservation values for woodland birds. The study outcomes have important implications for research and management of regrowth vegetation, both within Australia and internationally. From an international perspective, the study highlights the need for greater consideration of the importance of regrowth forest in a landscape context for conserving and restoring fauna communities. From an Australian perspective, the study provides important baseline information for the conservation and management of woodland bird habitat in fragmented brigalow landscapes. Prior to this research, very little was known on the spatial ecology of woodland birds in the region. The study highlights the important conservation values of small and often linear mature brigalow patches for woodland birds and the considerable potential for restoration of habitat for a diverse range of species through the retention of regrowth vegetation. In particular, the research outcomes suggest that targeting the retention of regrowth towards increasing the size and reducing the isolation of mature brigalow forests may be an effective strategy to maximise biodiversity benefits. Brigalow regrowth stands will need to be retained for at least 60 years and probably longer to maintain viable woodland bird communities. For this to happen on a regional-scale, brigalow regrowth needs to be given greater recognition for potential biodiversity benefits either within a legislative framework or by incentive schemes to promote the long term persistence of regrowth habitat within the landscape.

The conversion of native forests to pastures and crops is one of the most extensive causes of deforestation worldwide. Concomitant with agricultural landscape modification are the processes of habitat loss and fragmentation, which are major causes of species’ extinctions, population declines and altered ecosystem functions. However, in many tropical, sub-tropical and temperate regions, abandoned agricultural lands are reverting to regrowth or secondary forest, which represents an important opportunity for passive landscape restoration. Regrowth may be particularly important in highly modified landscapes, where the area of mature forest may be insufficient to support viable plant and animal communities without some form of restoration. Some studies of fauna populations in regrowth forest have found recovery of species richness within several decades, although recovery of species composition may take at least 100 years and some species may be permanently lost. While these findings are encouraging, they generally fail to account for the landscape context in which regrowth occurs and focus mainly on tropical forests. The aim of this thesis was to advance the understanding of fauna recovery in regrowth forests on abandoned agricultural land by: i) comparing woodland bird communities in a replicated chronosequence of semi-arid sub-tropical regrowth forests; and ii) quantifying how the ecological values of regrowth habitat vary among stand-, patch- and landscape-levels of ecological organisation. A review of 68 studies of fauna recovery in regrowth forests, revealed that current knowledge is limited by the predominance of studies conducted: in tropical rainforests; with minimal replication of sites; in landscapes within proximity of large tracts of relatively undisturbed mature forests; and with limited consideration of the influence of the spatial context on fauna recovery in regrowth forest. This study makes a significant contribution to understanding fauna recovery in regrowth forests by quantifying the recovery of estimated bird species richness to levels similar to mature forest, within a period of 30-60 years, in highly modified semi-arid agricultural landscapes in sub-tropical Australia. An ordination of the similarity in species composition among forest types also suggested that after 30-60 years regrowth bird communities are more similar to mature brigalow forest than the younger regrowth. This is important for the recovery of brigalow ecosystems, an endangered ecological community where regrowth is currently given minimal protection from further clearing. Comparisons of the importance of habitat attributes using model averaging and hierarchical partitioning of generalised linear models of the species richness of woodland birds showed that bird species richness was positively associated with patch age, and that stand-level factors such as grazing disturbance and the abundance of mistletoes (Amyema spp.) were also important. The spatial context of vegetation patches (size, shape and isolation) was equally important for bird species richness, with more species of woodland dependent, nectar/frugivores and non-ground foraging insectivores occurring in less modified landscape contexts, and the converse for generalist species, ground foraging insectivores and granivores. While a number of woodland dependent bird species known to be in decline in temperate woodlands of southern Australia were absent or rare in regrowth forests, several species (e.g., eastern yellow robin) also occupied regrowth habitats. This finding suggests that these more sensitive species may respond positively to landscape restoration through targeted retention of brigalow regrowth. The landscape-level amount of forest varied in importance among regrowth age classes and bird groups. In general, the amount and number of mature forest patches in the landscape were of lower importance than local attributes. However, the amount of mature forest and old regrowth (> 30 years) in the landscape did have an important positive influence on the number of woodland bird species and species’ abundance; suggesting that regrowth is making an important contribution to landscape recovery in the study area. Mistletoe abundance was strongly dependent on particular species of frugivores for seed dispersal (e.g., mistletoebird, spiny-cheeked honeyeater and painted honeyeater), and varied considerably among three sub-regions of the study area. In general, mistletoe abundance increased in linear patches and more highly modified landscapes but was also dependent on the abundance of seed dispersers and brigalow stand condition. These findings suggest that narrow linear patches in brigalow landscapes can have important conservation values for woodland birds. The study outcomes have important implications for research and management of regrowth vegetation, both within Australia and internationally. From an international perspective, the study highlights the need for greater consideration of the importance of regrowth forest in a landscape context for conserving and restoring fauna communities. From an Australian perspective, the study provides important baseline information for the conservation and management of woodland bird habitat in fragmented brigalow landscapes. Prior to this research, very little was known on the spatial ecology of woodland birds in the region. The study highlights the important conservation values of small and often linear mature brigalow patches for woodland birds and the considerable potential for restoration of habitat for a diverse range of species through the retention of regrowth vegetation. In particular, the research outcomes suggest that targeting the retention of regrowth towards increasing the size and reducing the isolation of mature brigalow forests may be an effective strategy to maximise biodiversity benefits. Brigalow regrowth stands will need to be retained for at least 60 years and probably longer to maintain viable woodland bird communities. For this to happen on a regional-scale, brigalow regrowth needs to be given greater recognition for potential biodiversity benefits either within a legislative framework or by incentive schemes to promote the long term persistence of regrowth habitat within the landscape.

La desertificació és un problema de degradació de sòls de gran importància en regions àrides, semi-àrides i sub-humides, amb serioses conseqüències ambientals, socials i econòmiques com a resultat de l'impacte d'activitats humanes en combinació amb condicions físiques i medi ambientals desfavorables (UNEP, 1994).L'objectiu principal d'aquesta tesi va ser el desenvolupament d'una metodologia simple per tal de poder avaluar de forma precisa l'estat i l'evolució de la desertificació a escala local, a través de la creació d'un model anomenat sistema d'indicators de desertificació (DIS). En aquest mateix context, un dels dos objectius específics d'aquesta recerca es va centrar en l'estudi dels factors més importants de degradació de sòls a escala de parcel.la, comportant un extens treball de camp, analisi de laboratori i la corresponent interpretació i discussió dels resultats obtinguts. El segon objectiu específic es va basar en el desenvolupament i aplicació del DIS.L'àrea d'estudi seleccionada va ser la conca de la Serra de Rodes, un ambient típic Mediterràni inclòs en el Parc Natural del Cap de Creus, NE Espanya, el qual ha estat progressivament abandonat pels agricultors durant el segle passat. Actualment, els incendis forestals així com el canvi d'ús del sòl i especialment l'abandonament de terres són considerats els problemes ambientals més importants a l'àrea d'estudi (Dunjó et al., 2003).En primer lloc, es va realitzar l'estudi dels processos i causes de la degradació dels sòls a l'àrea d'interés. En base a aquest coneixement, es va dur a terme la identificació i selecció dels indicadors de desertificació més rellevants. Finalment, els indicadors de desertificació seleccionats a escala de conca, incloent l'erosió del sòl i l'escolament superficial, es van integrar en un model espaial de procés.Ja que el sòl és considerat el principal indicador dels processos d'erosió, segons la FAO/UNEP/UNESCO (1979), tant el paisatge original així com els dos escenaris d'ús del sòl desenvolupats, un centrat en el cas hipotétic del pas d'un incendi forestal, i l'altre un paisatge completament cultivat, poden ser ambients classificats sota baixa o moderada degradació. En comparació amb l'escenari original, els dos escenaris creats van revelar uns valors més elevats d'erosió i escolament superficial, i en particular l'escenari cultivat. Per tant, aquests dos hipotètic escenaris no semblen ser una alternativa sostenible vàlida als processos de degradació que es donen a l'àrea d'estudi. No obstant, un ampli ventall d'escenaris alternatius poden ser desenvolupats amb el DIS, tinguent en compte les polítiques d'especial interés per la regió de manera que puguin contribuir a determinar les conseqüències potencials de desertificació derivades d'aquestes polítiques aplicades en aquest escenari tan complexe espaialment.En conclusió, el model desenvolupat sembla ser un sistema força acurat per la identificació de riscs presents i futurs, així com per programar efectivament mesures per combatre la desertificació a escala de conca. No obstant, aquesta primera versió del model presenta varies limitacions i la necessitat de realitzar més recerca en cas de voler desenvolupar una versió futura i millor del DIS. / The aim of this research was to develop a simple methodology for precisely appraising the status and trends of desertification in a semi-arid Mediterranean catchment, through a so-called desertification indicator system (DIS).The assessment of land degradation processes at plot scale was conducted through the monitoring of runoff-erosion microplots. As a result, a set of variables such as soil erosion, soil organic matter and vegetation cover, were identified as the most important factors for soil quality in the target area, and some of these were applied as inputs in the DIS model, accounting for their relevance not only at the plot but also at catchment scale. Regarding the parameter sensitivity of the DIS model, the saturated hydraulic conductivity as well as the erodability factor were identified as the most sensitive variables, whereas the soil-b parameter and also the vegetation cover and the slope angle were revealed as those affecting soil erosion and overland flow the least. Likewise, the model showed greater sensitivity to the dry than to the normal or wet rainfall scenarios. From the results of a plot scale model validation exercise it may be concluded that the behaviour of runoff and erosion at plot scale is somewhat different to that at the landscape scale: a scaling problem. At the plot scale, soil erosion was greatly overestimated by the model in the least vegetated environments and especially under cultivated olive trees, whilst it was slightly underestimated in the most vegetated ones (e.g. dense cork trees). The same pattern was found for overland flow, although measured and modelled runoff data were in the same order of magnitude and so errors were smaller than for erosion. Nevertheless, results may be considered significant in terms of which land uses are the most and least potentially degraded and in this way, the model fulfils its objective as a desertification support tool as it identifies the patterns of change expected, if not the magnitudes. The model would need to be more complex, have better and more input data and a regional scale validation if the magnitudes were to be predicted reliably.Since soil loss is considered the main indicator of soil erosion processes, according to FAO/UNEP/UNESCO (1979), the original landscape as well as the two developed scenarios, one related to a hypothetical landscape after a wildfire and another to a completely cultivated landscape, may be classified as being under low to moderate land degradation. In comparison to the original scenario, both developed scenarios were revealed to have higher soil erosion and runoff rates, especially the cultivated scenario. Hence, these two scenarios seem not to be a sustainable alternative to land degradation processes in the study area. However, a wide range of alternative scenarios may be developed with the DIS model, based on policies of particular relevance to the region and which help to determine the potential desertification consequences of these policies in this spatially complex landscape.

In an European context of agricultural land abandonment, the role of the farming community as landscape stewards is crucial for maintaining the rural landscape as well as the ecosystem services provided by this landscape. Such stewardship is studied here by assessing the participation of the farming community in the management of Menorca Biosphere Reserve, a small Mediterranean island with very well conserved and rich rural landscape which is not escaping this tendency of land abandonment. A survey of 41 farms and interviews with 15 stakeholders were performed in order to assess the role of the farming community in participatory management processes and the effectiveness of the Menorca Biosphere Reserve Agency (MBRA) in facilitating their participation.The results show that the participatory activities of the MBRA are effective and highly valued by participating stakeholders but could be improved by: 1) engaging non-associated farmers and traditional farmers in the MBRA activities 2) finding a consensual and long-term solution on issues related to the access to private rural land 3) providing rapid feedback to participants after meetings and 4) transforming the MBRA structure in order to deal with changes and an uncertain future. Failing to do this could illegitimate further participatory activities, erode trust among stakeholders and alienate the farming community and the society, thereby affecting the maintenance of the rural landscape.This case study highlights the importance of appropriate management structure for adaptive co-management to benefit from the participation of stakeholders in general and farmers in particular. The findings should be of interest to managers, scholars and practitioners using adaptive co-management approaches to manage complex social-ecological systems such as rural, cultural landscapes.

The work presented in this Doctoral Thesis has studied the temporal and spatial patterns of the most relevant soil parameters with special attention posed to soil biological and biochemical dynamics occurring at the studied soils in a very fragile area at Cap de Creus Peninsula, NE Spain. The main objective was to establish evidence of soil quality through the study of soil carbon dynamics (loss and storage) and their interactions with soil ecosystems. Soil environments were classified in terms of degree of soil quality, relating soil properties with plant cover species, especially along a sequence of agricultural abandonment where perturbations like wildfire and strong downpours often cause regressive dynamics in the natural succession of spontaneous vegetation and start erosion and degradation processes. At this regard, when fire occurrence is frequent, a quick drop down of all soil attributes was recorded leading to loss of biodiversity and, ultimately, desertification. / El treball de tesi doctoral ha estudiat els trets espacials i temporals de paràmetres mes rellevants del sòl, amb especial atenció en la dinàmica biològica i bioquímica que es dona en un àrea molt fràgil situada en la Península del Cap de Creus, NE Espanya. L’objectiu principal ha estat establir la qualitat dels sòls mitjançant l’estudi de la dinàmica del carboni (pèrdues i embornals) i la interacció amb l’ecosistema sòl. Els ambients estudiats s’han classificats en termes de qualitat del sòl, relacionant les seves propietats amb la coberta vegetal, especialment al llarg d’una seqüència d’abandonament agrícola on la presencia de pertorbacions com incendis o pluges causen sovint una dinàmica regressiva en la successió natural de la vegetació espontània i activen processos d’erosió i degradació. Tanmateix, en cas d’incendis freqüents, es registra un ràpid deteriorament de les propietats del sòl que provoca una pèrdua de biodiversitat i, mes tard, una desertificació.