Search Results (53)

Birds select habitats to optimize resources and maximize fitness, with some species recently colonizing new areas, like the Eurasian collared dove (ECD) in the Iberian Peninsula. The ECD spread across Europe in the early 20th century from South Asia. This study reanalyzes data from the Atlas of Breeding Birds in the Province of Alicante (SE Spain) to identify macrohabitat-level environmental variables related to its occurrence and abundance in this semi-arid Mediterranean landscape during the breeding season. We performed Hierarchical Partitioning analyses to identify important environmental variables for the species associated with natural vegetation, farming, topography, hydrographical web, urbanization, and climate. Results show that ECD has a higher occurrence probability near anthropic areas (isolated buildings, suburban areas), water points (medium-sized ponds), larger crop surfaces (total cultivated area), and warmer localities (thermicity index). The species avoids natural habitats like pine forests and scrublands. Abundance is positively linked to anthropic features like larger suburban areas and urban-related land uses. These findings can help predict its expansion in regions with a Mediterranean climate in South America, North America, or Australia, and its continuous natural expansion and population increase within the Mediterranean basin and Europe. Full article

Florida, USA, has 215 endemic or near-endemic plant species, most of which are found in scrubland and pine flatwood habitats and some of which are globally threatened or endangered. Florida is also one of the most rapidly urbanizing states in the United States, and natural lands are being rapidly replaced by urban development in this state. Conservation easements and nature preserves are two tools for sustaining biodiversity in urbanizing landscapes. This collection of images documents observational research on rare and endemic wildflower species in the nature preserves of Hillsborough County, Florida (population of 1.5 million), part of the larger Tampa metropolitan area (population of 3.2 million). A two-year survey of wildflowers in 27 nature preserves dispersed throughout the county’s total 3.3 km² area observed 410 species across 97 families. Of these 410 species, there were 19 species endemic to Florida, including the critically globally endangered Florida goldenaster (Chrysopsis floridana). Each of these endemic species relies on the unique soil and hydrologic conditions of the Florida scrubland and flatwood ecosystems, and preservation of these lands amidst urban development is critical for their conservation. The objective of this work is to document the role of the nature preserves as habitats for rare and endemic wildflower species, with the goal of providing science-based support for maintaining preserve land within and near urbanizing areas. Full article

The ‘Fragas do Eume’ Natural Park includes one of the best-preserved Atlantic forests in Europe. These forests are part of the Natura 2000 Network. This scientific study focuses on analysing land-cover changes in the ‘Fragas do Eume’ Natural Park (NW Spain) over a 25-year period, from 1997 to 2022, using machine learning techniques for the classification of satellite images. Several image processing operations were carried out to correct radiometry, followed by supervised classification techniques with previously defined training areas. Five multispectral indices were used to improve classification accuracy, and their correlation was evaluated. Land-cover changes were analysed, with special attention to the transitions between eucalyptus plantations and native deciduous forests. A significant increase in eucalyptus plantations (48.2%) (Eucalyptus globulus Labill.) was observed, while native deciduous forests experienced a decrease in their extent (17.6%). This transformation of the landscape affected not only these two habitats, but also cropland and scrubland areas, both of which increased. Our results suggest that the lack of effective conservation policies and the economic interest of fast-growing tree plantations could explain the loss of native deciduous forests. The results highlight the need to implement pro-active and sustainable management measures to protect these natural forest ecosystems in the ‘Fragas do Eume’ Natural Park. Full article

Hydrological Ecosystem Services (HES) are crucial components of environmental sustainability and provide indispensable benefits. The present study identifies critical hot and cold spots areas of HES in the Aglar watershed of the Indian Himalayan Region using six HES descriptors, namely water yield (WYLD), crop yield factor (CYF), sediment yield (SYLD), base flow (LATQ), surface runoff (SURFQ), and total water retention (TWR). The analysis was conducted using weightage-based approaches under two methods: (1) evaluating six HES descriptors individually and (2) grouping them into broad ecosystem service categories. Furthermore, the study assessed pixel-level uncertainties that arose because of the distinctive methods used in the identification of hot and cold spots. The associated synergies and trade-offs among HES descriptors were examined too. From method 1, 0.26% area of the watershed was classified as cold spots and 3.18% as hot spots, whereas method 2 classified 2.42% area as cold spots and 2.36% as hot spots. Pixel-level uncertainties showed that 0.57 km² and 6.86 km² of the watershed were consistently under cold and hot spots, respectively, using method 1, whereas method 2 identified 2.30 km² and 6.97 km² as cold spots and hot spots, respectively. The spatial analysis of hot spots showed consistent patterns in certain parts of the watershed, primarily in the south to southwest region, while cold spots were mainly found on the eastern side. Upon analyzing HES descriptors within broad ecosystem service categories, hot spots were mainly in the southern part, and cold spots were scattered throughout the watershed, especially in agricultural and scrubland areas. The significant synergistic relation between LATQ and WYLD, and sediment retention and WYLD and trade-offs between SURFQ and HES descriptors like WYLD, LATQ, sediment retention, and TWR was attributed to varying factors such as land use and topography impacting the water balance components in the watershed. The findings underscore the critical need for targeted conservation efforts to maintain the ecologically sensitive regions at watershed scale. Full article

There is growing concern about effectively controlling cat populations due to their impact on biodiversity, especially on islands. To plan this management, it is essential to know the cat population size, sterilization rates, and space they use. Small inhabited islands can have very high cat densities; thus, this study aimed to evaluate cat density and home range on a small tourist island in the Spanish Mediterranean. Surveys in the urban area identified individual cats using a photographic catalog, and camera trapping was conducted in the scrubland area. GPS devices were fitted on three urban cats. The overall cat density was estimated to be 308 cats/km², varying between the urban area (1084 cats/km²) and the uninhabited scrubland (27 cats/km²). Urban cats had smaller average home ranges (0.38 ha or 1.25 ha, depending on the estimation method) compared to scrubland cats (9.53 ha). Penetration of scrubland cats into the urban area was not detected. These results indicate that the urban area acts as a source of cats for the scrubland. Although the total sterilization rate was high (90.3%), the large cat population implies that the density would take over a decade to decrease to acceptable levels. Therefore, complementary measures for managing this cat population are recommended. Full article

In this study, the effects of different stocking rates were quantified in three study areas in a Mediterranean forest (Cuenca, Spain) by applying a multiparametric soil quality index (SQI) developed from undisturbed forest soils (>40 years). The main objective was to advance the development and application of multiparametric indices that allow for soil condition assessment. To fulfill this objective, the effectiveness of the developed multiparametric soil quality index (SQI) was analyzed as an indicator of livestock impacts on soil in the Mediterranean forest. The control areas without livestock activity were forest stands of different ages (a thicket forest stand of <30 years; a high-polewood forest stand of 30–60 years; and an old-growth forest stand of >60 years), which were compared with areas subjected to various grazing intensities (areas with permanent livestock passage: a sheepfold that had been inactive for 2–3 years and an active sheepfold; areas with intermittent livestock passage: a bare-soil area, a pine stand and a scrubland). The applied multiparametric soil quality index (SQI) was sensitive to changes in forest ecosystems depending on the stocking rates. However, to obtain greater precision in the assessment of the effects of stocking rates, the multiparametric index was recalibrated to create a new index, the Soil Status Index by Livestock (SSI_L). The correlation between the quality ranges obtained with both indices in different study areas suggests that the SSI_L can be considered a livestock impact reference indicator in Mediterranean forest soils. Full article

One of the primary tools used for determining the origin of a wildfire is analyzing burn patterns formed during the fire progression. These patterns, called fire pattern indicators, are interpreted and used to document the direction of fire movement at specific points, creating a directional map back to the specific area of origin. This concept was first set forth in 1978 by a U.S. governmental organization, the National Wildfire Coordinating Group (NWCG). Their recommendations are currently (2016) in the third edition, and in our study, we examine these indicators. Specifically, the objective was to perform a validation exercise where controlled burns were conducted of natural vegetation plots but augmented with 32 identical sets of staged artifacts which would provide additional opportunities for fire movement to create observable directional fire pattern indicators. Three adjacent plots were burned, each using a single point ignition, all located on level, scrubland terrain. The burns were conducted in the fall season, under low to moderate burning conditions. The research was structured as a preliminary study, since only mild terrain and weather conditions were encompassed. The actual fire movements were documented by drone videos, additional ground-based videos, and still photography. Within the three burn plots, a total of 12 data sites out of 32 data sites were selected: each one containing 7 to 12 individual artifacts. Each artifact was photographically documented post-fire, and the actual fire movement direction at that location was established. Assessment entailed the use of four experienced wildland fire investigators, with each one independently assessing the direction and type of fire spread at each artifact using the photographic site evidence. An analysis was then conducted to make a statistical comparison between the actual fire movement direction and the direction estimates provided by the experts analyzing the photographic evidence and the limited information on conditions provided. The results indicate an average error of 103°. These results indicate that additional efforts are needed to study the scientific basis of the indicators and to evolve improvements in both the indicators and in the accompanying guidance to investigators. Full article

Land use change (LUC) has direct and indirect consequences on soil quality. To gain insight into how LUC influences the physical properties of soil, it can be advantageous to compare undisturbed ecosystems with those that have naturally evolved over time, as well as to use soil quality indices to pinpoint the sensitivity of each ecosystem and land use change (LUC). A soil survey was carried out in the six major ecosystems of the Nilgiri Hill Region: cropland (CL), deciduous forest (DF), evergreen forest (EF), forest plantation (FP), scrubland (SL), and tea plantation (TP), with those having an establishment for over 50 years being selected and analyzed for soil physical parameters. In addition, soil quality indices were also derived to pinpoint the vulnerability of each ecosystem to LUC. The results reveal that the changes in land use significantly altered the soil physical properties. The content of clay was higher in EF and DF and increased with the soil profile’s depth, whereas the sand content was higher in CL and TP and decreased with the depth increment. BD and PD were significantly lower in EF, DF, SL, and FP, whereas they were higher in CL and TP. PS and ASM followed a similar trend to BD and PD. Owing to undisturbed natural settings, an abundance of litter input, and higher carbon concentrations, the HC was higher in EF, DF, SL, and FP, whereas, in the case of anthropogenic-influenced ecosystems such as CL and TP, it was lower. We discovered that LUC has altered Ag S, WSA, and MWD. Due to tillage and other cultural practices, Ag S, WSA, and MWD were significantly lower in CL and TP. However, the results confirm that native ecosystems (EF and DF) with a higher carbon content prevent such degradation, thereby resulting in good Ag S, WSA, and MWD. Full article

The ecosystem service value (ESV) gradient-evolution pattern of a river basin’s land and water-intertwined zones has a variety of ecosystem service values, such as biodiversity conservation, water conservation, water purification, etc. The study of the ecosystem service value (ESV) gradient-evolution pattern of a river basin’s land and water-intertwined zones will provide a scientific basis for the construction and protection of the ecological security pattern of the river basins. In this study, we combined the unit area equivalent factor method and geographically weighted regression (GWR) model to classify and analyze the gradient change pattern of ESV upstream, downstream, and along the river of the Guangdong mainstream section of the Xijiang River in China, and the conclusions are as follows: (1) The corresponding ESV share of each land use type was in the following order: water bodies > broad-leaved forest > artificial wetland > scrub > paddy field > coniferous forest > natural wetland > grassland. The level of each type of ESV does not depend entirely on the size of the area but is determined by the ecosystem service functions it can provide and the level of ESV per unit area; (2) the relationship between land use types along both sides of the river in the Guangdong section of the Xijiang River Basin shows a tendency to shift from water ecosystems to terrestrial ecosystems, and the ESV gradually decreases with the increase in distance from the water. (3) The upstream to the downstream area showed a trend of changing from terrestrial ecosystems to aquatic ecosystems, such as broad-leaved forests, scrublands, water bodies, artificial wetlands, etc., and the mean land ESV showed a general trend of undulating change and decline with the reduction in the distance from the downstream area. (4) Natural factors, such as the topography and geomorphology of the basin and the socio-economic factors of power consumption, influence the spatial distribution characteristics of the ESV in the region; among them, socio-economic factors, such as total power consumption, industrial exhaust gas emissions, industrial wastewater emissions, etc., in the economically developed areas of the Xijiang River Basin are the determinants of the changes in ESV, which are generated by human living and production activities, and these indirectly affect the magnitude of the ESV by influencing the factors of temperature and gas. Full article

Soil microorganisms play an important role in urban green spaces by providing ecological functions. However, information on the structure and assembly of microbial communities and the public risk of pathogenic bacteria in urban green spaces remains elusive. Here, we conducted a field survey on soil organisms in different vegetation cover types of urban green spaces (e.g., grasslands, shrublands, and woodlands) based on 16 S rRNA gene amplicon sequencing. We found that soil microbial communities in grasslands were dominated by Pseudomonadota, Acidobacteriota, Actinomycetota, and Chloroflexota. The diversity and niche breadth of the microbial communities in grasslands showed differences compared to shrublands and woodlands. Stochastic processes, which contribute to community assembly in grasslands, were lower compared to shrublands and woodlands, dominating the soil microbial community assembly of urban green spaces. Compared with soil microbial communities in scrublands and woodlands, the network of soil microbial communities in grasslands was simpler and had a weaker stability. Furthermore, the value of the microbial index of pathogenic bacteria in the observed green spaces was 0.01, which means that the risk of potential pathogens in green spaces was low. This study provides crucial information for the sustainable management of urban green spaces by regulating soil microorganisms, offering novel insights into the public health risks associated with potential pathogenic bacteria in these green spaces. Full article

Climate change and land use and land cover (LULC) change are impacting the species’ geographic distribution, causing range shifts and reducing suitable habitats. Asphodelus bento-rainhae subsp. bento-rainhae (AbR) is an endangered endemic plant restricted to Serra da Gardunha (Portugal), and knowledge of those changes will help to design conservation measures. MaxEnt was used to model AbR’s current distribution and project it into the future, 2050, using the Shared Socioeconomic Pathway SSP3-7. The Portuguese LULC maps from 1951–1980, 1995, 2007, and 2018 were used to assess and quantify LULC changes over time. The results showed that the AbR current predicted distribution matches its actual known distribution, which will not be affected by future predicted climate change. The significant LULC changes were observed during the study periods 1951–1980 to 2018, particularly between 1951–1980 and 1995. Scrubland and Agriculture decreased by 5% and 2.5%, respectively, and Forests increased by 4% in the study area. In the occurrence area, Agriculture increased, and Forests decreased between 1980 and 2018, due to Orchard expansion (34%) and declines in Chestnut (16.9%) and Pine (11%) areas, respectively. The use of species distribution models and the LULC change analysis contributed to understanding current and future species distribution. The LULC changes will have a significant impact on future species distribution. To prevent the extinction of this endemic species in the future, it is crucial to implement conservation measures, namely species monitoring, replantation, and germplasm conservation, in addition to guidelines for habitat conservation. Full article

Land use change is a crucial driving factor in hydrological processes. Understanding its long-term dynamics is essential for sustainable water resources management. This study sought to quantify and analyze land use change between 1985 and 2021 and its impacts on the hydrology of the Sejnane watershed, northern Tunisia. Remote sensing and a SWAT model using the SUFI-2 algorithm to identify the most sensitive parameters were used to achieve this objective. Land use maps were developed for 1985, 2001 and 2021. For the last 37 years, the watershed experienced a slight decrease in forest, scrubland and forage crops, a significant reduction in grassland, and a conspicuous expansion of olive trees and vegetable crops. Given the scarcity of observed discharge data, a SWAT model was calibrated for the period 1997–2010 and validated for 2011–2019. Model performance was good for both calibration (NSE = 0.78, PBIAS = −6.6 and R² = 0.85) and validation (NSE = 0.70, PBIAS = −29.2 and R² = 0.81). Changes in land use strongly affected the water balance components. Surface runoff and percolation were the most influenced, showing an increase in runoff and a decrease in percolation by 15.5% and 13.8%, respectively. The results revealed that the construction of the Sejnane dam, the extension of irrigated perimeters and olive tree plantations were the major contributors to changes in hydrology. Full article

In the upper vegetation limit of the Andes, trees change to shrub forms or other life forms, such as low scrubs. The diversity of life forms decreases with elevation; tree life forms generally decrease, and communities of shrubs and herbs increase in the Andean highlands. Most of treeline populations in the northwestern Argentina Altiplano are monospecific stands of Polylepis tarapacana, a cold-tolerant evergreen species that is able to withstand harsh climatic conditions under different life forms. There are no studies for P. tarapacana that analyze life forms across environmental and human impact gradients relating them with environmental factors. This study aims to determine the influence of topographic, climatic, geographic and proxies to human uses on the occurrence of life forms in P. tarapacana trees. We worked with 70 plots, and a new proposal of tree life form classification was presented for P. tarapacana (arborescent, dwarf trees, shrubs and brousse tigrée). We describe the forest biometry of each life form and evaluate the frequency of these life forms in relation to the environmental factors and human uses. The results show a consistency in the changes in the different life forms across the studied environmental gradients, where the main changes were related to elevation, slope and temperature. Full article

Accelerating land-use change (LUC) in the Nilgiri Hill Region (NHR) has caused its land to mortify. Although this deterioration has been documented, the destruction of buried gem soil has not been reported. Therefore, this study was conducted to assess the impact of LUC on soil-carbon dynamics in the six major ecosystems in the NHR: croplands (CLs), deciduous forests (DFs), evergreen forests (EFs), forest plantations (FPs), scrublands (SLs), and tea plantations (TPs). Sampling was conducted at selected sites of each ecosystem at three depth classes (0–15, 15–30, and 30–45 cm) to quantify the carbon pools (water-soluble carbon, water-soluble carbohydrates, microbial biomass carbon, microbial biomass nitrogen, dehydrogenase, and different fractions of particulate organic carbon). We found that the LUC significantly decreased the concentration of carbon in the altered ecosystems (49.44–78.38%), with the highest being recorded at EF (10.25%) and DF (7.15%). In addition, the effects of the LUC on the aggregate size of the organic carbon were dissimilar across all the aggregate sizes. The relatively high inputs of the aboveground plant residues and the richer fine-root biomass were accountable for the higher concentration of carbon pools in the untouched EFs and DFs compared to the SLs, FPs, TPs, and CLs. The results of the land-degradation Index (LDI) depicted the higher vulnerability of TP (−72.67) and CL (−79.00). Thus, our findings highlight the global importance of LUC to soil quality. Henceforth, the conservation of carbon pools in fragile ecosystems, such as the NHR, is crucial to keep soils alive and achieve land-degradation neutrality. Full article

An abandoned sphalerite mining area in the southwest (SW) of the Iberian Peninsula was studied to evaluate the impact that the presence of metal(loid)s has on soil and ecosystem health. Five zones were delimited: sludge, dump, scrubland, riparian zone, and dehesa. Critical total levels of lead (Pb), zinc (Zn), thallium (Tl), and chromium (Cr), well above the limit indicative of toxicity problems, were found in the areas close to the sources of contamination. Pb-Zn concentrations were very high in the riparian zone, reaching values of 5875 mg/kg Pb and 4570 mg/kg Zn. The whole area is classifiable as extremely contaminated with Tl, with concentrations above 370 mg/kg in the scrubland. Cr accumulation mainly occurred in areas away from the dump, with levels up to 240 mg/kg in the dehesa. In the study area, several plants were found growing luxuriantly despite the contamination. The measured metal(loid)s content is the cause of a significant decrease in ecosystem services, resulting in unsafe soils for food and water production, so the implementation of a decontamination program is advisable. The plant species Retama sphaerocarpa, present in the sludge, scrubland, riparian zone, and dehesa, is postulated as suitable for use in phytoremediation. Full article