Cristina Aponte

• PhD Ecology
• Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria

Ergosterol is a sterol compound present in fungal cell membranes and is used as a biomarker to measure fungal biomass. Therefore, an accurate analytical method is essential to quantify the presence of ergosterol in any soil type, regardless of its physicochemical characteristics or environmental conditions. The main objective of our study was to op...

Introduction/Aim: Riparian forests have a variety of interlinked habitats and are resource-rich with high biodiversity, but often converted to agricultural land uses. Associated changes to mycorrhizal communities may limit the reestablishment of native plants. We asked if the origin of soil inoculum influenced plant growth traits, foliar nutrients,...

Straw helimulching was applied to an area with a high soil erosion risk one month after the Navalacruz megafire (Iberian Central System, Ávila, Spain) to mitigate soil erosion and to maintain soil quality. To determine whether the soil fungal community, which is key to soil and vegetation recovery after fire, is altered by straw mulching, we examin...

The FireFungi project

Previous attempts to quantify tree abundance at global scale have largely neglected the role of local competition in modulating the influence of climate and soils on tree density. Here, we evaluated whether mean tree size in the world’s natural forests alters the effect of global productivity on tree density. In doing so, we gathered a vast set of...

Live fuel moisture content (LFMC) influences many fire-related aspects, including flammability, ignition, and combustion. In addition, fire spread models are highly sensitive to LFMC values. Despite its importance, LFMC estimation is still elusive due to its dependence on plant species traits, local conditions, and weather patterns. Although LFMC m...

Purpose Owing to their topographic location and nutrient rich soils, riparian forests are often converted to pastures for grazing. In recent decades, remnant riparian forests cleared for grazing pastures have been restored with native species. The impacts of such land-use changes on soil fungal communities are unclear, despite the central roles tha...

The structure and functioning of temperate forests are shifting due to changes in climate. Foreseeing the trajectory of such changes is critical to implementing adequate management practices and defining long-term strategies. This study investigated future shifts in temperate forest species composition and abundance expected to occur due to climate...

Research note to summarise research into the variation in soil bacterial and fungal communities across three different land uses.

While products generated at global levels provide easy access to information on forest growing stock volume (GSV), their use at regional to national levels is limited by temporal frequency, spatial resolution, or unknown local errors that may be overcome through locally calibrated products. This study assessed the need, and utility, of developing l...

Forest fire severity influences post-fire fuel structure and thus the behaviour of subsequent fires. Understanding such interactions is critical to improving predictions of fire risk and emergency management, yet few studies have quantified fire severity effects on fuel attributes. We quantify fuel structure of a fire-tolerant eucalypt forest 7 yea...

Dead wood, including dead standing trees (DST) and coarse woody debris (CWD), is a critical component of forest ecosystems that provides habitat and refugia for fauna, flora, and microbial communities and plays a key role in carbon and nutrient cycling. However, few studies have modelled the long-term dynamics of dead wood, limiting our ability to...

Riparian forests were frequently cleared and converted to agricultural pastures, but in recent times these pastures are often revegetated in an effort to return riparian forest structure and function. We tested if there is a change in the soil bacterial taxonomy and function in areas of riparian forest cleared for agricultural pasture then revegeta...

Modeling and forecasting forest evolution in the context of climate and socio-economic change is a challenge for the scientific community. This paper aims to calibrate the LANDIS-11 simulation model for a type of forest ecosystem by introducing climate scenarios and forecast of its dynamics under different forest management practices. The area use...

Wildfires have increased in size and frequency in recent decades in many biomes, but have they also become more severe? This question remains under-examined despite fire severity being a critical aspect of fire regimes that indicates fire impacts on ecosystem attributes and associated post-fire recovery. We conducted a retrospective analysis of wil...

More tree species can increase the carbon storage capacity of forests (here referred to as the more species hypothesis) through increased tree productivity and tree abundance resulting from complementarity, but they can also be the consequence of increased tree abundance through increased available energy (more individuals hypothesis). To test thes...

Wildfires worldwide are becoming more frequent but are they also becoming more severe? Here we used remotely sensed burn-severity data from wildfires in Victoria, southeastern Australia to address that question. We selected 162 wildfires of more than 1000 ha that occurred over the past 30 years across a wide range of forest types. Spectral indices...

Riparian ecosystems are among the most degraded worldwide as they are subject to a range of human-mediated disturbances at different scales. As riparian vegetation plays a key role in maintaining waterway and landscape health, restoration often focuses on promoting riparian vegetation re-establishment. The role of below-ground processes and agents...

Understanding the extent of heterogeneity in soil microbial community structure and function at different scales within vegetation communities is critical to designing appropriate sampling protocols. Environmental factors (e.g. disturbance) make sampling in the riparian zone particularly challenging as vegetation communities are highly heterogeneou...

Soil organic carbon (SOC) stocks in Australia’s temperate forests have been overlooked in national soil databases and in global SOC analyses of natural ecosystems despite the importance of temperate forests to the global terrestrial carbon balance. This limits the potential to both predict change in SOC stocks in temperate Australia and to identify...

The International Scientific Conference „Forest Science for a Sustainable Forestry and Human Wellbeing in a Changing World” - INCDS „Marin Drăcea” 85 Years of Activity, Centenary of The Great Union in 1918” is an open scientific event dedicated to the anniversary of 85 years of activity in forestry research of the National Institute for Research an...

Assessing the possibility of implementing a national forest monitoring system based on Earth Observation technologies Programs developed in national bio-monitoring networks, such as ICP-Forests, have limitations due to local micro-climatic variations that are difficult to assess. Therefore, new technologies (e.g., remote sensing) are needed to asse...

Aim Forest carbon storage is the result of a multitude of interactions among biotic and abiotic factors. Our aim was to use an integrative approach to elucidate mechanistic relationships of carbon storage with biotic and abiotic factors in the natural forests of temperate Australia, a region that has been overlooked in global analyses of carbon‐bio...

According to the competitive exclusion principle, species with low competitive abilities should be excluded by more efficient competitors; yet, they generally remain as rare species. Here, we describe the positive and negative spatial association networks of 326 disparate assemblages, showing a general organization pattern that simultaneously suppo...

Machine learning and spectral index (SI) thresholding approaches have been tested for fire-severity mapping from local to regional scales in a range of forest types worldwide. While index thresholding can be easily implemented, its operational utility over large areas is limited as the optimum index may vary with forest type and fire regimes. In co...

The fire-tolerant eucalypt forests of south eastern Australia are assumed to fully recover from even the most intense fires; however, surprisingly, very few studies have quantitatively assessed that recovery. The accurate assessment of horizontal and vertical attributes of tree crowns after fire is essential to understand the fire’s legacy effects...

Fire-tolerant eucalypt forests of south eastern Australia are assumed to fully recover from even the most intense fires but surprisingly very few studies have quantitatively assessed that recovery. Accurate assessment of horizontal and vertical attributes of tree crowns after fire is essential to understand the fire’s legacy effects on tree growth...

Revegetation is a key activity in many ecological restoration projects. Commonly used revegetation techniques involve planting nursery-grown plants or sowing seed directly on site. However, the role of below-ground processes and agents in facilitating successful revegetation outcomes is often overlooked, even though agents like mycorrhizal fungi ar...

Introduction. Mycorrhizal symbioses are important in facilitating plant establishment and survival, these plant-fungi interactions may be key to the successful revegetation of disturbed or degraded environments. To date few studies have focused on the changes in mycorrhizal communities with revegetation and fewer still have included analysis of veg...

Natural and anthropogenic disturbances pose a significant threat to forest condition. Continuous, reliable and accurate forest monitoring systems are needed to provide early warning of potential declines in forest condition. To address that need, state-of-the-art simulations models were used to evaluate the utility of C-, L- and P-band synthetic ap...

Introduction. Riparian ecosystems are among the most degraded worldwide as they are subject to a range of human-mediated disturbances at different scales. As riparian vegetation plays a key role in maintaining waterway and landscape health, restoration often focuses on promoting riparian vegetation re-establishment. The role of below-ground process...

Non-native tree (NNT) species have been transported worldwide to create or enhance services that are fundamental for human well-being, such as timber provision, erosion control or ornamental value; yet NNTs can also produce undesired effects, such as fire proneness or pollen allergenicity. Despite the variety of effects that NNTs have on multiple e...

Restoration success is underpinned by soil communities and microorganisms as they influence plant growth, establishment and survival. Symbiotic mycorrhizal fungi promote plant growth, nutrient acquisition, plant defence, aid in water acquisition, buffer against toxic levels of trace elements in contaminated land and increase a plant’s ability to to...

Spectral indices derived from optical remote sensing data have been widely used for fire 14-severity classification in forests from local to global scales. However, comparative analyses of 15 multiple indices across diverse forest types are few. This represents an information gap for fire 16 management agencies in areas like temperate southeastern...

Introduction / Aim: Restoration success is underpinned by soil communities and microorganisms as they influence plant growth, establishment and survival. Microbial community profiles enable the investigation of soil functional groups and how the use of carbon sources changes along a restoration trajectory.Plant establishment and survival are closel...

Natural disturbances significantly influence forest ecosystem services and biodiversity. Accurate delineation and early detection of areas affected by wind and insect outbreaks are crucial for guiding management decisions. To this end, past studies relied mostly on passive sensors (e.g., optical), and active sensors (i.e., radar) were rarely used....

This poster represents an overall study design for my PhD research project.

The carbon stability of fire-tolerant forests is often assumed but less frequently assessed, limiting potential to anticipate threats to forest carbon posed by predicted increases in forest fire activity. Assessing the carbon stability of fire-tolerant forests requires multi-indicator approaches that recognise the myriad of ways that fires influenc...

Context Australia’s temperate forest landscapes encompass broad topographic and edaphic ranges, and are regularly disturbed by fire. Nonetheless, relative contributions of environmental heterogeneity, disturbance regimes, and dispersal limitations to plant species turnover remain poorly understood. Objectives To evaluate the relative influences of...

Functional diversity and composition of soil bacterial communities affect important soil biogeochemical processes. In natural and semi-natural ecosystems, variations in habitat complexity have been shown to significantly impact both litter and soil bacterial communities. However, this remains largely untested in urban ecosystems, where human manage...

Aim In boreal forest ecosystems plant productivity is typically constrained by mineral nutrient availability. In some boreal regions changes in nutrient availability have led to limited changes in productivity but large changes in plant composition. To determine the impact that a change in nutrient availability has on the plant communities it is im...

Mixed-species eucalypt forests of temperate Australia are assumed tolerant of most fire regimes based on the impressive capacity of the dominant eucalypts to resprout. However, empirical data to test this assumption are rare, limiting capacity to predict forest tolerance to emerging fire regimes including more frequent severe wildfires and extensiv...

Management strategies such as planned burning for fuel reduction can help mitigate the effects of wildfires. The amount of biomass consumed is of interest to fire managers as reduction of fuel loads is imperative to reducing the risk and extent of a wildfire event. Biomass regeneration is also of importance for ecosystem recovery and resilience. Py...

Monitoring fire effects at landscape level is viable from remote sensing platforms providing repeatable and consistent measurements. Previous studies have estimated fire severity using optical and synthetic aperture radar (SAR) sensors, but to our knowledge, none have compared their effectiveness. Our study carried out such a comparison by using ch...

Fires affect wide areas and their effects can be successfully estimated from a range of remote sensing sensors, with synthetic aperture radars (SAR) being of particular interest due to their sensitivity to forest vertical structure, global availability and independence of cloud cover or solar elevation. Previous studies have demonstrated the sensit...

Timely information on spatial variation of live fuel moisture is critical for fire risk assessment and behaviour modelling. Using an airborne synthetic aperture radar system, the sensitivity of radar data to live fuel (i.e. canopy foliage) moisture was evaluated. Field and airborne measurements were collected over a 3-week period in a semiarid Aust...

Mast-seeding species exhibit not only a large inter-annual variability in seed production but also considerable variability among individuals within the same year. However, very little is known about the causes and consequences for population dynamics of this potentially large between-individual variability. Here, we quantified seed production over...

We report on the successful propagation of the sedge Gahnia radula (R.Br.) Benth. from seed by using plant tissue culture, and its successful establishment in the field. This keystone species, although common along parts of the eastern coast of Australia, is currently not available for revegetation because of a lack of efficient propagation methods...

Urban ecosystems are frequently characterized by simplified structures compared to the surrounding natural ecosystems, which in turn control microclimate, habitat and resources for soil organisms and consequently soil processes depending upon them. While various studies have investigated leaf litter decomposition processes in forest remnants along...

Previous studies have found negligible effects of single prescribed fires on coarse woody debris (CWD) but the cumulative effects of repeated low-intensity prescribed fires are unknown. This represents a knowledge gap for environmental management because repeated prescribed fires are a key tool for mitigating wildfire risk, and because CWD is recog...

Aims The extent to which the spatial and temporal patterns of soil microbial and available nutrient pools hold across different Mediterranean forest types is unclear impeding the generalization needed to consolidate our understanding on Mediterranean ecosystems functioning. Methods We explored the response of soil microbial, total, organic and inor...

This letter evaluates the biomass-retrieval error in pine-dominated stands when using high-spatial-resolution airborne measurements from fully polarimetric L-band radar and airborne laser scanning sensors. Information on total above-ground biomass was estimated through allometric relationships from plot-level field measurements. Multiple-linear-reg...

Growth is one of the most important phenological cycles in a plant's life. Higher growth rates increase the competitive ability, survival and recruitment and can provide a measure of a plant's adaptive capacity to climate variability and change. This study identified the growth relationship of six Eucalyptus species to variations in temperature, so...

Cork oaks (Quercus suber L.) are key tree species at Doñana Biological Reserve (DBR), Huelva, Spain. Sampling was conducted on a total of 13 trees exhibiting symptoms of decline (foliar wilting and defoliation, branch dieback and root necrosis). In 2008 Phytophthora cinnamomi was isolated from feeder roots of one tree and Pythium spiculum from two...

We synthesise a series of independent but integrated studies on the functioning of a mixed Mediterranean oak forest to demonstrate the tree–soil interactions underpinning a positive feedback process that sustains the coexistence of two oak species. The studies focused on the foliar functional traits, plant regeneration patterns, biogeochemical cycl...

Fully polarimetric C- and L-band synthetic aperture radar (SAR) data have been investigated to determine the relationship between polarimetric target decomposition components and forest burn severity over two sites located in a Mediterranean environment. The dependence of the polarimetric decomposition metrics on SAR acquisition geometry and enviro...

Tree species can affect the decomposition process through the quality of their leaf fall and through the species-specific conditions that they generate in their environment. We compared the relative importance of these effects in a two-year experiment. Litterbags containing leaf litter of the winter-deciduous Quercus canariensis, the evergreen Q. s...

Background and aims Soil factors are driving forces that influence spatial distribution and functional traits of plant species. We test whether two anchor morphological traits—leaf mass per area (LMA) and leaf dry matter content (LDMC)—are significantly related to a broad range of leaf nutrient concentrations in Mediterranean woody plant species. W...

Questions: What is the spectrum of variability of chemical elements in a Mediterranean forest ecosystem across the different compartments? Do co-existing tree species with different leaf chemical composition and nutrient cycling distinctly modify soil conditions? Could these species-specific, tree-generated soil changes create a potential positive...

Cork oaks are considered keystone structures in the ecosystem of the stabilised sands of the Doñana National Park. These remnant big trees are threatened by nesting of colonial waterbirds (whose debris induce deep soil chemical changes) and by two pathogenic oomycetes, Phytophthora cinnamomi and Pythium spiculum. We analyzed the distribution of sev...

Conservation management conflicts frequently arise when an overpopulation of a protected organism has negative effects on other valuable elements in the same ecosystem. We studied the interactions between a colony of protected tree-nesting wading birds and a remnant population of centenarian cork oaks that was part of the formerly dominant forests...

In Mediterranean ecosystems the effect of aboveground and belowground environmental factors on soil microbial biomass and nutrient immobilization,release cycles may be conditioned by the distinctive seasonal pattern of the Mediterranean,type climates. We studied the effects of season, canopy cover and soil depth on microbial C, N and P in soils of...

Species in temporary ponds overcome periods of unfavorable weather conditions by building up a large seed bank. With this strategy, the species diversity of ponds is preserved and information on their dynamics and structure is retained. Little is known about the characteristics, spatial patterns and role in the vegetation dynamics of the soil seed...

Centennial cork oaks (Quercus suber L.) are spread in the sandy soils of Doñana (S. W. Spain). They are remnants from the formerly extended oak forests that were overexploited during the XVII-XX centuries. After the protection of the area as Biological Reserve forty years ago, all silvicultural practices such as cutting, pruning and cork extraction...

Host trees can modify their soil abiotic conditions through their leaf fall quality which in turn may influence the ectomycorrhizal (ECM) fungal community composition. We investigated this indirect interaction using a causal modelling approach. We identified ECM fungi on the roots of two coexisting oak species growing in two forests in southern Spa...

Recibido el 21 de enero de 2011, aceptado el 4 de febrero de 2011. Aponte, C. (2011). Interacciones planta-suelo en un bosque mediterráneo. Ecosistemas 20(2-3):95-100. En los sistemas forestales los árboles y el matorral son capaces de modular la disponibilidad de recursos necesarios para otros organismos tales como la luz, la temperatura, la humed...