Edge Vegetation Research Articles

The Use of the Normalized Difference Red Edge (NDRE) Vegetation Index from Multispectral Cameras Mounted on Unmanned Aerial Vehicle to Estimate the Nutrient Content in Oil Palm Leaves

This study aimed to develop a prediction model for the nutrient content of N, P, K, Mg, and Ca in oil palm leaves using the Normalized Difference RedEdge (NDRE) vegetation index derived from multispectral camera data. Data acquisition was carried out by an unmanned aerial vehicle (UAV), which was correlated to leaf sample analysis of the 17th frond number. Results showed that simple regression analysis successfully represented nutrient content (N, P, K, Mg, and Ca) based on NDRE values. Based on the MAPE and Correctness values, the nutrient content prediction model for N and P yields reliable results, while for K, Mg, and Ca, they are considered good, with Correctness values of 95.5%, 96.6%, 88.8%, 87.3%, and 90.0% for N, P, K, Mg, and Ca, respectively. The study found that the NDRE vegetation index can be used to predict the nutrient content of oil palm leaves with reliable results in accuracy for N and P, and good accuracy for K, Mg, and Ca. This is a promising finding, as it could lead to the development of a non-destructive and rapid method for monitoring the nutrient status of oil palm trees, with the validation models for N, P, K, Mg, and Ca are yN = 1.1089x - 0.2497, yP = 0.99x + 0.002, yK = 1.204x - 0.1576, yMg = 0.9149x + 0.0183, and yCa = 1.0418x - 0.0218. Keywords: Multispectral Cameras, Oil Palm, Leaf Nutrient Contents, Prediction.

Jaguar predation on domestic horses in the dry forest of northwestern Costa Rica

AbstractDepredation of domestic horses (Equus caballus) by jaguars (Panthera onca) is an example of human–wildlife conflict that has not received much attention. We monitored spatio‐temporal activity and distribution of horses in a 2.64‐km2 fenced area in the dry forest of northwestern Costa Rica in response to 16 jaguar killings of horses during January‐November 2017. We monitored 4 horses (2 males, 2 females) equipped with global positioning system transmitters from February‐September 2018 to identify daily and seasonal patterns of use of cover types and a water source by horses. We then compared these results to the previous locations where jaguars killed horses to identify the circumstances under which horses seemed more vulnerable to jaguar predation. Based on 1,693 locations, horses spent most time in grassland (92%) rather than forest and edge vegetation (8%) and used a core area of 0.74 km2 (kernel density estimation) to 0.86 km2 (minimum convex polygon). Of 16 horse predation events by jaguars, 9 events (56%) occurred in grasslands, 4 in forested areas (25%), and 3 in the forest edge (19%), indicating predation events occurred disproportionately from expected counts based on horse use of vegetation. The predation sites were characterized by a higher proportion of edge and a lower proportion of forest compared to a random points. We suggest that when horses explored areas near the edge of forested areas, the chances of being preyed on by jaguars increased.

VedgeSat: An automated, open‐source toolkit for coastal change monitoring using satellite‐derived vegetation edges

AbstractPublic satellite platforms offer regular observations for global coastal monitoring and climate change risk management strategies. Unfortunately, shoreline positions derived from satellite imagery, representing changes in intertidal topography, are noisy and subject to tidal bias that requires correction. The seaward‐most vegetation boundary reflects a change indicator which shifts on event–decadal timescales, and informs coastal practitioners of storm damage, sediment availability and coastal landform health. We present and validate a new open‐source tool VedgeSat for identifying vegetation edges (VEs) from high (3 m) and moderate (10–30 m) resolution satellite imagery. The methodology is based on the CoastSat toolkit, with streamlined image processing using cloud‐based data management via Google Earth Engine. Images are classified using a newly trained vegetation‐specific neural network, and VEs are extracted at subpixel level using dynamic Weighted Peaks thresholding. We performed validation against ground surveys and manual digitisation of aerial imagery across eroding and accreting open coasts and estuarine environments at a site in Scotland. Smaller‐than‐pixel vegetation boundary detection was achieved across 83% of Sentinel‐2 imagery (Root Mean Square Error of 9.3 m). An overall RMSE of 19.0 m was achieved across Landsat 5 & 8, Sentinel‐2 and PlanetScope images. Performance varied by coastal geomorphology, with highest accuracies across sandy open coasts owing to high spectral contrast and less false positives from intertidal vegetation. The VedgeSat tool can be readily applied in tandem with waterlines near‐globally, to support adaptation decisions with historic coastal trends across the whole shoreface, even in normally data‐scarce areas.

A Model Of Wave Attenuation In Vegetated Environments

Mangrove degradation and rapid coastline erosion have been widely observed at many locations along the Mekong Delta Coast. These locales frequently display narrow mangrove forests, occasionally spanning as few as 100 meters. This phenomenon of the narrower mangrove forests is supposed to be due to the construction of sea dikes in a search to establish room for agricultural purposes and to hinder the salinity intrusion, referred to as "mangrove squeeze". Within the context of monitoring mangrove forest evolution alongside the shoreline's dynamic processes of erosion and accretion, the hypothesis of a "squeeze mangrove forest" was advanced by Phan (2015) and Truong (2017). This conceptual construct underscores the fundamental importance of "mangrove width" as a critical length scale influencing the sustainable growth of a mangrove forest. The physical interpretation of this length scale is intricately tied to the extent of the mixing layer's intrusion into the vegetative domain (Truong et al., 2019). It is important to note that while the mixing dynamics of estuarine mangroves are primarily regulated by lateral flow events induced by large vortex structures moving along the vegetation edge, the characteristics of incoming waves primarily determine the length to which the mixing layer penetrates within coastal mangroves. The latter is the primary focus of this study.

Integrated drag coefficient formula for estimating the wave attenuation capacity of Rhizophora sp. mangrove forests

Recently, bulk drag coefficient (C˜D) formulations used to quantify wave energy dissipation by Rhizophora mangroves were developed from laboratory data; however, these formulations have not yet been validated with field data. Additionally, due to the complex geometry of mangrove trees within forests and spatial variability, common criteria for determining the adequate geometric characteristics of mangrove forests are lacking and are required to obtain accurate definitions for C˜D. This paper addresses these knowledge gaps by proposing a newly integrated C˜D formulation based on the comprehensive characterization of a Rhizophora mangle forest combined with wave measurements in field, and by using numerical modeling for the calibration process. The field campaign consisted of 23 continuous days of recorded wave data and spatial distribution observations of the geometric characteristics of the mangrove forest. The variation in frontal area per unit height per square meter (Ahm) along the mangrove forest was reported for three zones with different densities identified along the study transect, with decreasing root density from the vegetation edge to the forest interior. On average, the incident wave height decreased by 34% at 63 m in mangrove forests, and the wave attenuation ratios (r) varied between 0.001 and 0.01 m-1. To estimate the C˜D values associated with these wave height attenuation ratios, the Simulating Waves Nearshore (SWAN) numerical model was used to calibrate the model results with the field observations. The variation in the tree frontal area along the mangrove forest and the wave conditions at the site are considered during the calibration process. To further characterize C˜D for this type of mangrove species, the C˜D values acquired from the calibration together with the values reported in the literature from laboratory experiments are presented as a function of the Keulegan-Carpenter number (KC). Root diameter is defined as the characteristic length according to the inherent geometric characteristics of a Rhizophora sp. forest. The new formulation allows us to predictably estimate C˜D values that can be used as inputs in drag force-based models to estimate the attenuation of wave energy produced by Rhizophora sp. forests.

Adapting Methods For Bed Level Assessment In And Around Submerged Vegetation

Coastal vegetation has the capacity to reduce flow and orbital velocities near the bed and stabilize the sediment with its root network. As a result it has an effect on sediment dynamics which gains increasing attention as ecosystem service in coastal protection. To quantify and predict this ecosystem service, laboratory experiments with live or artificial vegetation are often conducted. During these experiments the assessment of bed level change is challenged by the presence of the vegetation. Standard optical and acoustic measurement techniques cannot obtain data below vegetation canopies. Especially for submerged flexible vegetation like seagrass, this challenge is aggravated for airborne methods that require flume drainage (e.g. terrestrial laser scanning) (Follett and Nepf, 2012). Flexible blades will spread on the ground during drainage, potentially covering meadow edges and thus excluding areas of interest from the bed level analysis. Moreover, live aquatic vegetation may be stressed by air exposure, if the facility is drained for bed level measurements. This potentially leads to different, non-natural behaviour in consecutive experiments. And finally, draining and refilling the facility is time consuming, especially as it needs to be done very carefully as not to disturb any generated bedforms. This time aspect hampers the collection of time series and thus the assessment of the development of bed level changes with airborne methods. Underwater technology like sonar and echo sounder avoid shading of areas by spread-out vegetation, but are equally not capable of obtaining data below vegetation canopies. Moreover, instruments that can obtain spatially resolved data underwater often require a minimum water depth which may exceed the water depth relevant for experiments with vegetation. In intertidal areas (e.g. salt marshes) the challenge of obtaining bed level data below vegetation canopies is overcome by the use of a sediment-erosion-bar (SEB) (Cahoon et al., 2002). For this method a horizontal bar is installed at a fixed height above the ground and the distance between this bar and the ground is measured at defined locations along the bar and set time intervals to obtain information on the bed level change. SEBs have successfully been adapted to laboratory settings in the past (Spencer et al., 2016), but still required flume drainage. We applied this method in an undrained flume to assess sediment dynamics in and around an artificial seagrass meadow. Additionally, we tested underwater photogrammetry to obtain 3D-spatial information (e.g., 3D models) on bed level and bedforms at and near the vegetation edges. Photogrammetry has been successfully applied to obtain bedform information in the presence of seagrass stands, but to date still required the drainage of the facility (Meysick et al., 2022).

Assessment of the spectral misalignment effect (SMILE) on EarthCARE's Multi-Spectral Imager aerosol and cloud property retrievals

Abstract. The Multi-Spectral Imager (MSI) on board the Earth Cloud, Aerosol and Radiation Explorer (EarthCARE) will provide horizontal information about aerosols and clouds. These measurements are needed to extend vertical cloud and aerosol property information, which is obtained from EarthCARE's active sensors, in order to obtain a full three-dimensional view of cloud and aerosol conditions. Mesoscale weather systems, in particular, will be characterized. The discovery of a non-compliance of the MSI visible–near-infrared–shortwave infrared (VNS) camera’s visible (VIS) and shortwave infrared (SWIR1) channels regarding a spectral central wavelength (CWVL) shift across-track of up to 14 nm (VIS) and 20 nm (SWIR1) led to the need for an analysis regarding its impact on MSI Level-2A aerosol and cloud products. A significant influence of the spectral misalignment effect (SMILE) on MSI retrievals is identified due to the spectral variation in gas absorption, surface reflectance, and aerosol and cloud properties within the spectral ranges of these MSI bands. For example, the VIS channel is positioned in close proximity to the red edge of green vegetation and is impacted by residual absorption of water vapor and ozone. Small central wavelength variations introduce uncertainties due to the rapid change in surface reflectance for conditions with low optical thickness. The present central wavelength shift in the VIS towards shorter wavelengths than at nadir introduces a relative error in transmission of up to 3.3 % due to the increasing influence of water vapor and ozone absorption. We found relative errors in the top-of-atmosphere (TOA) signal due to the SMILE of up to 30 % for low optical thickness over a land surface in that band. Since the magnitude of the impact strongly depends on the underlying surface and atmospheric conditions, we conclude that accounting for the SMILE in Level-2 retrievals or correcting the Level-1 signal will improve MSI aerosol and cloud product quality.

Edge effects of a fragmented seagrass habitat on flow, bivalve recruitment, and sediment dynamics

In both continuous and fragmented seagrass ecosystems, the vegetation edge can be a location of abrupt hydrodynamic change, with impacts to both ecological and physical processes. We address how flow and wave activity change across seagrass meadow edges and the effects of vegetation on sediment dynamics and bivalve recruitment. Two Zostera marina seagrass meadow sites were monitored: a high-density site with >500 shoots m-2 and a low-density site with <250 shoots m-2. Mean flow velocities were significantly reduced in seagrass vegetation adjacent to edges, with reductions compared to unvegetated areas ranging from 30-75%. Recruitment of juvenile bivalves was significantly elevated within vegetation. No significant differences in wave activity or sediment suspension and/or deposition were found spatially across a 10 m distance from a seagrass edge, but significant temporal variability was observed, caused by periodic storms. Wave height was a major predictor for sediment movement along seagrass edges, with an observed 10-fold increase in sediment collection within benthic traps following severe storms. These results were found across various heterogeneous edge configurations and reveal abrupt hydrodynamic responses of both mean flow and turbulence to occur at short spatial scales (1-10 m), with changes to wave and sediment deposition and/or suspension conditions only occurring over larger spatial distances (~100 m). Changes to the hydrodynamic regime were therefore found to be driven by meteorological conditions (e.g. winds, storms) on daily timescales and by changes in seagrass shoot density, altering both bivalve recruitment and sediment dynamics on longer temporal and/or spatial timescales.

IMPACTS OF INTENSIVE AGRICULTURE ON BIRDS: A REVIEW

Intensive agriculture has had a negative impact on biodiversity and human health across the world. Specifically, bird populations have declined for many years due to soil degradation and agrochemical pollution. This review, which draws on 890 sources, including research articles and literature reviews, examines the interaction between birds and intensive agriculture to better understand its effects and conservation implications. Intensive agricultural activities have resulted in significant population declines among insectivorous and carnivorous birds, while generalist bird populations have increased. The heavy use of pesticides in intensive agriculture affects food availability for birds by reducing invertebrate and vertebrate populations as well as natural vegetation cover, which has a significant impact on bird diversity. Additionally, the accumulation of toxic compounds reduces bird reproductive success. In general, intensive agroecosystems have consistently had lower avian diversity than forest habitats and even lower-impact agricultural systems. However, some agroecosystems, such as rice fields, agricultural drainages, and canal systems, create alternative habitats that can benefit waterfowl. Future work should consider strategies such as restoring and enhancing vegetation edges, preserving natural vegetation, implementing organic farming practices, maintaining water bodies, and providing economic incentives for landowners to conserve biodiversity on their land to promote bird diversity conservation.

Radioactive remote signatures derived from Sentinel-2 images and field verification in West Sulawesi, Indonesia.

Mamuju, West Sulawesi, is an area in Indonesia with high radiation levels. A high radiation dose rate was detected in Adang volcanic rock. Activities related to radioactive minerals contained in rocks and soil may release hazardous radiation into the environment. The study area generally exhibits a highly irregular morphology that provides limited access because of the high slope gradient of the volcanic terrain. Therefore, it is challenging to identify and map minerals carrying radioactive elements via Sentinel-2 remote sensing. Since optical satellite images are superior in land cover detection, we proposed a mapping technique for radioactive carrier minerals based on vegetation indices verified by chlorophyll field measurements. We applied band rationing to identify the distribution of hydrothermal alteration minerals and vegetation stress, while field chlorophyll measurements of Dryopteris marginalis and Nephrolepis exaltata were conducted. The Sentinel-2 color composite of images with 4/2, 8A/11, and 11/12 RGB band ratios revealed the distribution of iron oxide, ferromagnesian silicates, and clay minerals. High levels of uranium (U) were scattered in leucite basalt rocks, with a broad distribution of iron oxide minerals and small amounts of ferromagnesian minerals. In contrast, the presence of thorium was not affected by the presence of these minerals. In addition, band rationing of chlorophyll spectra captured by the red edge vegetation index (REVI) was used as the basis for vegetation stress mapping related to radiation exposure based on the chlorophyll content in ferns in the study area. The REVI image showed an anomalous vegetation stress concordant with the high radioactivity. To obtain more accurate results, ground measurements were also performed to identify the vegetation stress due to the presence of minerals carrying radioactive elements. The areas with radioactive mineralization and vegetation stress were located upstream of the Mamuju River and the Botteng and Ahu areas in Tapalang.

Early-stage development of an artificial dune with varying plant density and distribution

For the optimal design of artificial dunes, a fundamental understanding of morphological changes throughout the early phases of dune growth is required. This study examines the effect of different vegetation densities and patterns on the subsequent dune development during the first three months following construction. Marram grass (0.40 m in height) was planted in six zones (20 × 20 m2) with three different densities (6, 9 and 15 plants/m2) and four different patterns (gridded, random, clustered, and staggered). Monthly drone surveys were combined with daily to weekly topographic RTK-GNSS surveys along 12 cross-shore profiles (two per zone). Beach wind conditions were continuously monitored with a meteorological station. Additionally, four aeolian sand transport measurements were conducted with Modified Wilson And Cook sand traps. Results demonstrate the importance of using a specific plant density as well as the use of spatial plant distribution. The use of a staggered or random plant distribution leads to the formation of narrower bedforms, while higher vegetation densities also result in narrower bedforms. Bedform height is greater in zones with high vegetation density. Regardless of plant density and distribution, each plantation zone experienced dune development with a volume of 6 m3/m, primarily influenced by the supply of aeolian sand from the adjacent beach. Aeolian sand transport rapidly decreases within a downwind distance of 20 m from the vegetation edge. The ability to trap sand varies between size of the plants, with wider plants being able to trap sand over shorter distances. By the end of the study period, nearly all vegetation zones were completely buried, causing sand to bypass the dune. The future progression of dune development will be determined by the interaction between vegetation growth and sand burial.

Updating forest road networks using single photon LiDAR in northern Forest environments

Abstract Knowledge about the condition and location of forest roads is important for forest management. Coupling accurate forest road information with planning and conservation strategies supports forest resource management. In Canada, spatial data of forestry road networks are available provincially; however, they lack spatial accuracy, and up-to-date information on key attributes such as road width is missing. In this study, we apply a novel approach to update forest road networks and characterize road conditions in Ontario’s Boreal and Great Lakes—St. Lawrence (GLSL) Forest regions. We use airborne laser scanning (ALS), to facilitate the identification of forest roads across densely forested landscapes. We categorized roads into four classes based on driveable width, edge vegetation, as well as surface and edge degradation as derived from high-density Single Photon LiDAR (SPL) data. Using a novel road extraction method, we produced a road probability raster and map road centerlines. We validated road location and attribute information using Global Navigation Satellite System (GNSS) ground truth data in two Ontario forest management units, in the boreal forest and the GLSL. Road segments in some regions have been altered to account for land cover changes, such as flooding or fallen trees. In other situations, the road path may deviate from the planned layout of the road, which is not always followed in the field. Our results highlight inaccuracies in the existing road networks, with 30 per cent of ‘Full access’ roads and 29 per cent of ‘Partial access’ roads being undriveable by standard vehicles and 45 per cent of ‘Status unknown’ roads, which make up 48 per cent of the pre-existing network, being driveable by standard vehicles. Results show that the average positional accuracy of updated road centerlines is 0.4 m, and the average road width error is 2 m. The production of spatially accurate forest road networks and road attribute information is important for characterizing large road networks for which often minimal information is available.

Analytical Modeling of Mean Velocity Profile through Two-Layered Fully Submerged Vegetation

The mean velocity distribution of open channel flows with fully submerged two-layered vegetation can be divided into three zones. Zone 1 represents the lower region of short vegetation, where the flow has high drag because of highly dense vegetation, Zone 2 represents the middle flow zone from the edge of the short vegetation to the top of the tall one, and Zone 3 denotes the upper region with the free surface flow. A new analytical model is developed based on the momentum equation of vegetated flow, where turbulent eddy viscosity is approximated as a linear relationship with local velocity. The analytical model was evaluated using seven experimental data sets under different flow conditions with distinctive densities and formations of vegetation. Three sets of data available from other researchers were also used to check the applicability of the proposed model. An agreement between the analytical model and experimental data indicates the validity and robustness of the model.

Structurally rich dry grasslands – Potential stepping stones for bats in open farmland

Agricultural intensification has caused decrease and fragmentation of European semi-natural dry grasslands. While a high biodiversity value of dry grasslands is acknowledged for plants and insects, locally and on landscape level, their relevance for mobile species, such as bats, is unknown. Here we investigate the use of dry grassland fragments by bats in an agriculturally intensified region in Germany and evaluate local and landscape factors influencing bat activity and assemblages. Specifically, we predicted that a combination of local dry grassland structural richness and landscape features as well as their interactions affect bat activity and foraging above dry grasslands. We also expected that these features influence compositions of local bat assemblages. We repeatedly sampled at 12 dry grassland plots with acoustic monitoring and assessed activity and foraging of bat species/sonotypes, which we grouped into guilds known for foraging in open land, at vegetation edges and in narrow spaces. We determined structural richness of the dry grassland plots in field and derived landscape features from digital landscape data. A relatively high proportion of bat species/sonotypes used dry grasslands regularly. The edge space foragers responded positively to higher local structural richness. Their dry grassland use increased when surrounding forests and woody features were less available, but they foraged more on dry grasslands closer to water bodies. Narrow space bat activity on dry grasslands decreased with less landscape connectivity. Open and narrow space foragers responded to local structural richness only in landscape context. For all bat guilds we found increased use of structurally richer dry grasslands when there was more open farmland in the surroundings. This was also the case for edge space foragers, when landscapes were more homogeneous. Lastly, with increasing structural richness, bat assemblages were more dominated by edge space foragers. We show the importance of European dry grassland fragments for the highly mobile group of bats under certain local structural and landscape compositional conditions. Our results underline the value of heterogeneous dry grassland fragments as potential stepping stones in intensively used farmland areas and contribute to evidence based decision making in dry grassland management and bat conservation.

COMMUNITY STRUCTURE OF MACROZOOBENTHOS AS BIOINDICATOR OF WATER QUALITY IN THE OGAN RIVER AROUND BATURAJA CITY

Macrozoobenthos has an important role in the waters. The river is one example of a water body where macrozoobenthos can be used as an indicator of water pollution. This study aims to calculate the community structure of macrozoobenthos and the water quality in the Ogan River around Baturaja City. Sampling was carried out by purposive sampling method in 5 stations, in which each station had 5 sampling points determined based on differences in microhabitat, namely stonny, gravel, sandy, and litter conditions around the edge of vegetation. The results revealed that macrozoobenthos found in the Ogan River consisted of 6 classes (i.e., Bivalvia, Crustacea, Gastropods, Insecta, Oligochaeta, and Turbellaria), 12 orders, 21 families, and 30 genera. The density of macrozoobenthos species ranged from 598 to 1367 ind/m2. The diversity index value in the Ogan River around Baturaja City ranged from 1.117 to 2.22 with a moderate category. In addition, the community similarity index of the five stations reached ≥ 50%, except for stations III and V (44%). Seemingly that the macrozoobenthos community in the waters of the Ogan River around Baturaja City was relatively the same. Therefore, the community structure of the Ogan River around Baturaja City was relatively stable.

Natural Vegetation Edges Promote Bat Activity in Macadamia Orchards in Northeastern South Africa

Agricultural intensification can result in extremely fragmented landscapes with typically only small natural areas remaining. The South African macadamia industry is expanding dramatically, with over 5000 ha planted per year. Remaining natural vegetation around macadamia orchards will be key to retain important ecosystem services such as biological pest control of insects provided by, amongst others, insectivorous bats. We evaluated how the activity of bat species on macadamia farms within different land-use mosaics is related to general insect abundance and what role the phenological stages of macadamias play. Recordings of bat echolocation and insect light trap collections were conducted (July 2019 – March 2020) at different edges of land-use types on two macadamia farms in Hazyview, South Africa. Results showed that edge type significantly influenced bat activity and insect abundance with natural vegetation edges recording the highest bat activity (n = 3153) and insect abundance (n = 16 524). River edges (bat n = 1635, insect n = 11 284) presented lower activity and abundance than natural edges but still double that of road edges (bat n = 695, insect n = 3743). Bat activity was also higher during developing-nut and mature phenology stages when pest insects peak. Bats from all foraging guilds were recorded during the study, which points towards a more intact bat assemblage within the study area compared to other macadamia areas in South Africa. Our study highlights the importance of retaining natural vegetation within an agricultural land-use mosaic to maintain biological pest control.

Using hyperspectral indices for investigation polluted plants and soil in Abu Zabaal area, Egypt

The present work is the first attempt to monitor the spectroscopic characteristics of polluted plants in Abu Zabaal area. Spectral signatures for plants in the study area have been measured by ASD spectroradiometer to assess the status of plants species. Various hyperspectral indices of Plant and soil were calculated to evaluate the samples representing the soil and studied plant species. The analysis showed that chlorophyll a and b content decreased in all plant species under pollution in comparison with control ones. There is a change in chlorophyll fluorescence under pollution conditions. The experimental results were matching with the hyperspectral indices, especially the red edge vegetation indices (RE, MRENDVI, and RE-NDVI). Based on linear regression analyses, an innovative model for assessing HCO3% was generated using SAVI retrieved from hyperspectral data, giving a promising accuracy (90%).

Impacts of Landscape Type, Viewing Distance, and Permeability on Anxiety, Depression, and Stress.

Contact with nature is beneficial for mental health, including anxiety and stress. Exposure to virtual nature also has similar restorative traits with real nature. However, previous studies on the restorative environment mostly focus on ordinary people while caring less about patients with depressive disorders. Thus, the restorative impacts of virtual nature on patients with depression warrant examination. This research aims to study the restorative effects of virtual reality (VR) landscape type, viewing distance, and permeability on anxiety, depression, and stress in patients with depression. Study A revealed that the perceived restorative level of landscape type varies greatly: grassland > forest > water > undergrowth > urban square. Additionally, natural environments with higher openness, more green elements, more blue sky, and more sunshine exposure had higher restorative levels on perceived depression, anxiety, and stress relief. Study B found that the grassland landscape with a higher viewing distance and a medium vegetation edge permeability provides more restorative impacts for patients with depression.

Long-term shoreline evolution (Late-Holocene – 2018) of the Channel 15 coast (Samborombón bay, NE – Buenos Aires province, Argentina)

Here we present an investigation with the aim of reconstructing the shoreline evolution and geomorphological changes in the central zone of Samborombón bay (Channel 15, Buenos Aires province, Argentina) during the period 2700 cal yr BP to recent times. Palynological, geomorphological and historical imagery and proxy-data analyses were combined to reconstruct the shoreline evolution and paleo-environmental changes. Palynological material (pollen and non-pollen palynomorphs -NPP-) was recovered from a continuous 117 cm long sedimentary profile extracted from an outcrop at the northern margin of Channel 15. Relict landforms, including paleo- shorelines, were reconstructed by applying enhancing filters to a Spot 6 image from 2015. Historical shorelines were identified in high-definition images (aerial and satellite imagery) between 1968 and 2018, but also by using the marsh vegetation edge as a shoreline proxy. Shoreline change was quantified using the Net Shoreline Movement and Weighted Linear Regression algorithms in ArcMap 10.1. Results based on the palynological analysis for the period 2700–2740 BP, show the passage from subtidal-intertidal to supratidal environment with influence of brackish to fresh-waters, where paleo-shorelines imprint was recognized developing over a tidal plain that was grading to marshes. Results based on aerial and satellite imagery for the period 1968–2018 show shoreline retrocession only immediately at the north of the channel mouth, while the rest of the coast prograded toward the estuary. These processes indicate that new marshes – and, therefore, wetlands – are constantly developing at the edge of Samborombón bay.

Phytosociological and ecological peculiarities of Festuca pallens Host in Ukraine

Abstract This article deals with phytosociological and ecological requirements of the vulnerable species Festuca pallens in Ukraine. Based on the analysis of 51 relevés, we have recognized the occurrence of Festuca pallens in three associations within the Festuco-Brometea class. Some communities where Festuca pallens occurs have transitional stages of succession to forest edge vegetation according to the expert system classification. In addition, we evaluated the ecological differences among occupied habitats using Didukh’s phytoindication scales and concluded that the most important ecological factors are soil humidity, nitrogen content, soil aeration, salt regime, carbonate content, thermoregime, and climate continentality. Finally, we evaluated the threats to the existence of these communities with the presence of Festuca pallens, taking into account climate change and other impacts of anthropogenic activities (illegal mining, recreation, afforestation).