Woody Vegetation Structure Research Articles

Abundance and community structure of birds breeding in Kalahari woodland used as rangeland

The line transect method was applied to assess the linear index of abundance and community structure of birds breeding in an area of Kalahari woodland used as range land for cattle. Four transects were designed along roads traversing the ranch. Each transect was 2.5 km long and was surveyed three times in 2014 and 2015. A total of 47 bird species were recorded but only 25-31 species were recorded on any particular transect. In the neighbouring pristine Kalahari woodland, the number of bird species on a12 km long transect was much higher (n = 88), and ranged in some sections (each 1.2 km in length) from 35 to 53. On any particular section, the number of dominant species ranged from 5 to 7, and their cumulative dominance on each section was similar, ranging from 53-56 %, while the community dominance index ranged from 0.23 to 0.35. The most numerous species were the Cape turtle dove and emerald-spotted wood dove, which were dominant on all sections. Together they comprised 28 % of all breeding birds. The avian community in the Kalahari woodland in Sachinga LDC did not differ from the neighbouring pristine woodland either in terms of species diversity or evenness. However, it differed significantly in terms of species richness, the proportion of main ecological guilds, and linear index of abundance of particular species. These differences could be mainly due to the structure of woody vegetation, which is much thicker in Sachinga than in the pristine woodland not used as pasture for cattle. The thickening of this vegetation on the ranch could have been caused by heavy grazing pressure by the cattle. Data published through GBIF (Doi: https://doi.org/10.15470/rova7r)

Linking the spatiotemporal variation of litterfall to standing vegetation biomass in Brazilian savannas

Abstract Aims Litterfall at a global scale is affected by climate, edaphic features and vegetation structure, with litter production increasing from grasslands to forests following the rise in standing biomass. However, at landscape scales, the same relationship between litter production and vegetation structure has rarely been studied and comparisons of litterfall patterns between adjacent, structurally distinct communities are lacking. Here, we use a standardized methodology to describe the structural differences among four savanna physiognomies and analyze their relationship with changes in litterfall across the Cerrado. Methods We evaluated the woody vegetation structure and composition in 48 sites, equally distributed across four physiognomies and monitored the monthly litter production from April 2014 to March 2015. Important Findings Results showed that the density, basal area, cylindrical volume and aboveground biomass of woody vegetation differ among physiognomies, increasing consistently from cerrado ralo, cerrado típico, cerrado denso and cerradão. Indeed, we found a strong and positive relationship between aboveground biomass and annual litter production, with litter yield increasing from 0.9 to 8.4 Mg ha−1 across different physiognomies, following the increment in vegetation structure. Monthly production was seasonal and similar among vegetation types, increasing during the dry season. Leaves comprised the dominant fraction (approx. 85%) and litterfall seasonality primarily resulted from the concentration of leaf shedding during dry months. However, the temporal pattern of litterfall throughout the year showed a gradual reduction in the seasonality from open to closed vegetation types, likely following the decrease of deciduous species abundance in the plant community. Our results showed that changes in vegetation structure may affect spatial and temporal litterfall patterns in different physiognomies, which co-occur across the Cerrado landscape, with potential implications for the overall functioning of this ecosystem. Moreover, these findings highlight the use of standardized methods as essential to correctly compare litterfall patterns among different environments.

Woody Species Diversity, Vegetation Structure, and Regeneration Status of the Moist Afromontane Forest of Agama in Southwestern Ethiopia

This study was conducted in Agama Forest in Kafa Zone, Southwestern Ethiopia, to assess species diversity, vegetation structure, and regeneration status of woody species. A systematic sampling technique was employed to collect vegetation data. Sixty (60) sample plots of 25 m × 25 m were laid at 300 m intervals all along ten grids interspaced 800 m apart. Sample plots of 25 m × 25 m were used to record DBH and H of all woody plant species reaching a DBH >2.5 cm and height >2 m. For the inventory of seedling and sapling, two subplots of 2 m × 5 m were used at the beginning and the end of the baseline on opposite sides of the main quadrat. Vegetation data such as DBH, height, seedling, and sapling density of woody species were recorded in each plot. Altogether, 72 woody plant species of 65 genera and 35 families were identified. Analysis of selected tree species showed diverse population structures. This study showed that small trees and shrubs dominated the Agama Forest, which revealed its status under a secondary regeneration stage. Study on the structure and regeneration of some woody species indicated that there are species that require urgent conservation measures. Sound management and monitoring, as well as maintenance of biodiversity and cultural and economic values of the forest, require conservation activities that encourage sustainable uses of the forest and its products.

Applied nucleation facilitates tropical forest recovery: Lessons learned from a 15‐year study

Abstract Applied nucleation, mostly based upon planting tree islands, has been proposed as a cost‐effective strategy to meet ambitious global forest and landscape restoration targets. We review results from a 15‐year study, replicated at 15 sites in southern Costa Rica, that compares applied nucleation to natural regeneration and mixed‐species tree plantations as strategies to restore tropical forest. We have collected data on planted tree survival and growth, woody vegetation recruitment and structure, seed rain, litterfall, epiphytes, birds, bats and leaf litter arthropods. Our results indicate that applied nucleation and plantation restoration strategies are similarly effective in enhancing the recovery of most floral and faunal groups, vegetation structure and ecosystem functions, as compared to natural regeneration. Seed dispersal and woody recruitment are higher in applied nucleation and plantation than natural regeneration treatments; canopy cover has increased substantially in both natural regeneration and applied nucleation treatments; and mortality of planted N‐fixing tree species has increased in recent years. These trends have led to rapid changes in vegetation composition and structure and nutrient cycling. The applied nucleation strategy is cheaper than mixed‐species tree plantations, but there may be social obstacles to implementing this technique in agricultural landscapes, such as perceptions that the land is not being used productively. Applied nucleation is likely to be most effective in cases where: planted vegetation nuclei enhance seed dispersal and seedling establishment of other species; the spread of nuclei is not strongly inhibited by abiotic or biotic factors; and the approach is compatible with restoration goals and landowner preferences. Synthesis and applications. Results from our 15‐year, multi‐site study show that applied nucleation can be a cost‐effective strategy for facilitating tropical forest regeneration that holds promise for helping to meet large‐scale international forest restoration commitments.

Composition and Structure of Woody Vegetation in Community Compared to State Forests in Tehuledere District, South Wollo, Ethiopia

ABSTRACT Restoring the degraded areas with vegetation cover is an optimal strategy to mitigate land degradation. The objective of this study was to examine the composition and structure of woody vegetation in community and state forests in Tehuledere District, South Wollo, Ethiopia. The vegetation data were collected by sampling a total of 40 systematically laid sample plots (i.e. 20 samples in each forest type) and analyzed to determine woody species composition (i.e. number of species, frequency, density, dominance, and importance value index) and forest structure (i.e. diameter distribution, basal area, and biodiversity index). The vegetation structure was described by diameter class using inverse J-shaped as this type of distribution considered being indicative of a stable population structure or good regeneration status. The results revealed that significantly greater densities of seedlings and saplings were found in the community forest than that of the state forest. Moreover, a total of 45 woody species, representing 29 families were recorded in this forest. However, 29 woody species, representing 25 families were only found in the state forest, suggesting that 25 woody species were common in both forest types. However, 20 woody species were found only in the community forest, whereas only three species were exclusively obtained in the state forest. Woody plant densities were 10,881 and 9,501 individuals’ ha−1 in community and state forests, respectively. The result suggested that Juniperus procera was the most dominant species in both forest types. The community forest had a diversity value of 2.26, while the corresponding value for the state forest was only 2.07. Overall, as compared to the state forest, the community forest had a better status in several biological parameters. Generally, the results emphasize the importance of the relative advantage of the community forestry approach to restore, enhance, and maintain (e.g. enrichment planting, pruning, and selective cutting) the forest resources over the conventional or protectionist way of the state forest management. Therefore, intervention for legal framework and institutional development particularly through formal recognition of people’s ownership and right over the conservation management of forests is essential toward sustainable forestry.

Livestock browsing affects the species composition and structure of cloud forest in the Dhofar Mountains of Oman

AbstractQuestionsIt is frequently reported that overstocking of camels, cattle and goats is degrading the Anogeissus cloud forest, which is endemic to a 200‐km stretch of coastal mountains in southern Arabia. However, livestock impacts on the vegetation have not been assessed. Furthermore, we have a limited understanding of the impacts of large‐bodied browsing livestock, such as camels, in woodland and forest rangelands. Therefore, in this study, we examine the effects of livestock browsing on the species composition, density, and phytomorphology of woody vegetation in the Anogeissus cloud forests in the Dhofar Mountains of Oman.LocationData were collected at 30 sites in the Jabal Qamar mountain range in western Dhofar, Oman.MethodsThe point‐centred quarter method was used to sample the composition, density and structure of woody vegetation. Constrained correspondence analysis was used to quantify the effects of livestock browsing on woody plant species composition, whilst effects on plant density were analysed using mixed‐effects models. Standardised major axis regression was used to examine differences in height–diameter allometry (stunting) under different stocking rates.ResultsFog density, topographic position and long‐term stocking rates were found to be important factors affecting woody species composition. We found lower species diversity and plant density, and higher frequencies of unpalatable species, under higher stocking rates. Juveniles showed a stronger response to stocking rates than adults, and several common species exhibited stunted morphology under high stocking rates.ConclusionsBrowsing by large‐bodied livestock, such as camels and cattle, can substantially alter the species composition, structure, and phytomorphology of woody vegetation in semi‐arid woodlands and forests. Juveniles are particularly susceptible to browsing which alters woody vegetation demography and inhibits regeneration potential. Our results support previous suggestions of overstocking in Dhofar and highlight the importance of swift measures to reduce livestock browsing pressure in the Anogeissus cloud forests.

A multi-plot assessment of vegetation structure using a micro-unmanned aerial system (UAS) in a semi-arid savanna environment

Unmanned Aerial Systems (UAS) represent an important niche platform for measuring vegetation health, structure, and productivity; metrics that directly inform sustainable conservation and development initiatives in rural African savannas. Products derived from UAS imagery have much finer spatial resolutions than traditional satellite or aircraft imagery, allowing the spectral and structural heterogeneity of vegetation to be mapped and monitored with more detail, an advantage especially useful for challenging environments such as dryland savannas. This study uses UAS-captured imagery to assess the efficacy of UAS for monitoring structural characteristics of vegetation in a mixed savanna woodland. The main objective was to compare multiple approaches for extracting woody vegetation structure from UAS imagery and assess correlations between in situ field measurements and UAS estimates. We compare different sensor types to determine whether multispectral data improve estimates of vegetation structure at the expense of spatial resolution. Results indicate that leveraging multispectral reflectance information, particularly in the near-infrared portion of the spectrum, aids in crown delineation, areal estimates, and fractional cover of woody and non-woody vegetation within the study area. We also compare two image segmentation techniques for crown delineation and found that all techniques perform best in grassy savanna sites where trees and shrubs are easily distinguishable. Overall, a region-growing technique consistently exhibits highest levels of agreement with in situ height and crown area measurements, while a simple height threshold is best for determining fractional coverage of structural classes present. Findings from this work contribute to the advancement for applying high spatial resolution, UAS-derived methods in remote sensing analyses with specific consideration towards autonomous crown delineation and resource management initiatives in dryland systems. Lastly, data-informed analyses, as presented here, provide robust scientific evidence that contribute to informing environmental management decisions when considering the use of UAS technology in conservation and wildlife management across Africa.

Monitoring Woody Cover Dynamics in Tropical Dry Forest Ecosystems Using Sentinel-2 Satellite Imagery

Dry forests in Sub-Saharan Africa are of critical importance for the livelihood of the local population given their strong dependence on forest products. Yet these forests are threatened due to rapid population growth and predicted changes in rainfall patterns. As such, large-scale woody cover monitoring of tropical dry forests is urgently required. Although promising, remote sensing-based estimation of woody cover in tropical dry forest ecosystems is challenging due to the heterogeneous woody and herbaceous vegetation structure and the large intra-annual variability in the vegetation due to the seasonal rainfall. To test the capability of Sentinel-2 satellite imagery for producing accurate woody cover estimations, two contrasting study sites in Ethiopia and Tanzania were used. The estimation accuracy of a linear regression model using the Normalised Difference Vegetation Index (NDVI), a Partial Least Squares Regression (PLSR), and a Random Forest regression model using both single-date and multi-temporal Sentinel-2 images were compared. Additionally, the robustness and site transferability of these methods were tested. Overall, the multi-temporal PLSR model achieved the most accurate and transferable estimations (R2 = 0.70, RMSE = 4.12%). This model was then used to monitor the potential increase in woody coverage within several reforestation projects in the Degua Tembien district. In six of these projects, a significant increase in woody cover could be measured since the start of the project, which could be linked to their initial vegetation, location and shape. It can be concluded that a PLSR model combined with Sentinel-2 satellite imagery is capable of monitoring woody cover in these tropical dry forest regions, which can be used in support of reforestation efforts.

Can an herbivore affect where a top predator kills its prey by modifying woody vegetation structure?

In large mammal communities, little is known about modification of interspecific interactions through habitat structure changes. We assessed the effects of African elephants (Loxodonta africana) on features of woody habitat structure that can affect predator-prey interactions. We then explored how this can influence where African lions (Panthera leo) kill their prey. Indeed, lions are stalk-and-ambush predators and habitat structure and concealment opportunities are assumed to influence their hunting success. During 2years, in Hwange National Park, Zimbabwe, kill sites (n = 167) of GPS-collared lions were characterized (visibility distance for large mammals, distance to a potential ambush site and presence of elephant impacts). We compared characteristics of lion kill sites with characteristics of random sites (1) at a large scale (i.e. in areas intensively used by lions, n = 418) and (2) at the microhabitat scale (i.e. in the direct surrounding available habitat, < 150m, n = 167). Elephant-impacted sites had a slightly higher visibility and a longer distance to a potential ambush site than non-impacted sites, but these relationships were characterized by a high variability. At large scale, kill sites were characterized by higher levels of elephant impacts compared to random sites. At microhabitat scale, compared to the direct nearby available habitat, kill sites were characterized by a reduced distance to a potential ambush site. We suggest a conceptual framework whereby the relative importance of habitat features and prey abundance could change upon the scale considered.

Woody species composition, diversity and vegetation structure of two protected areas along a climatic gradient in Burkina Faso (West Africa)

Climate variability added to anthropogenic pressures leads to habitat fragmentation, degradation and loss of forest ecosystem resources in Burkina Faso. Studying vegetation structure and woody species composition is important in monitoring vegetation dynamics for efficient forest management. This study was carried out to characterize woody vegetation along a climatic gradient. Stratified sampling according to four vegetation types was conducted in 120 plots in two protected areas. The plot size was 30 m × 30 m in savannas and 50 m × 10 m in gallery forests. In each plot, all woody species with a diameter at breast height (DBH) ≥ 5 cm were systematically identified and measured. Diversity indices, structural parameters and species importance values were calculated and compared among the sites and vegetation types. Linear discriminant analysis (LDA) was used to characterize each vegetation type in each climatic zone. The species diversity, tree density and basal area of woody species increased significantly along the climatic gradient from north to south. Discriminant analysis identified two vegetation types: open vegetation (shrub savannas and tree savannas) with moderate species richness and structural characteristics and closed vegetation (woodland savannas and gallery forests) with higher species richness and structural characteristics. The size class distribution showed that irrespective of the climatic zone, each vegetation type has a stable structure. Compensation among species in different diameter classes does not allow the effect of the climatic gradient between the two sites on the diameter class size distribution to be observed. This study revealed that climate is the main driver influencing the diversity of woody species rather than the site-specific conditions at the two sites. In addition to climate, site ecological conditions affect the structural parameters. The results provide a rational basis for planning and management decisions to ensure the sustainable use of resources in the two protected areas.

WOODY SPECIES STRUCTURE, DIVERSITY AND FLORISTIC AFFINITIES IN SEASONALLY DRY FOREST IN THE UXMAL ARCHAEOLOGICAL ZONE

&lt;p&gt;Archaeological zones in Mexico effectively preserve the vegetal diversity within them. An analysis and description were done of woody vegetation structure, diversity and floristic affinity in the Uxmal Archaeological Zone, in the Puuc region of Yucatan, Mexico. Twenty quadrants measuring 10 x 10 m (100 m&lt;sup&gt;2&lt;/sup&gt;) were placed throughout the zone to sample its diverse substrates. Height and diameter at breast height (DBH) of woody species with DBH &amp;gt;1cm were measured in each quadrant. Floristic affinities were analyzed with a dendrogram generated using the Morisita-Horn index. A total of 1,622 individuals were recorded which belonged to 101 species and 76 genera from 31 families. The richest families were Fabaceae, Rubiaceae, Malvaceae, Polygonaceae and Euphorbiaceae. The species with the highest relative importance values were &lt;em&gt;Bursera simaruba&lt;/em&gt;,&lt;em&gt; Piscidia piscipula&lt;/em&gt;,&lt;em&gt; Diospyros anisandra&lt;/em&gt;,&lt;em&gt; Thouinia paucidentata&lt;/em&gt;,&lt;em&gt; Gymnopodium floribundum &lt;/em&gt;and &lt;em&gt;Lonchocarpus xuul&lt;/em&gt;. The most frequent species were &lt;em&gt;B. simaruba&lt;/em&gt; and &lt;em&gt;D. anisandra&lt;/em&gt;, those with the greatest density were &lt;em&gt;D. anisandra&lt;/em&gt; and &lt;em&gt;L. xuul&lt;/em&gt;, and the most dominant were &lt;em&gt;G. floribundum&lt;/em&gt; and &lt;em&gt;P. piscipula&lt;/em&gt;. Floristic affinity analysis identified three floristic groups: dry tropical forest; mixed seasonally flooded forest; and semi-evergreen tropical forest. Although relatively small in area, Uxmal has highly diverse microclimates and substrate types which support a diverse woody species composition, structure and physiognomy within the same seasonally dry tropical forest.&lt;/p&gt;

Mapping and Monitoring Fractional Woody Vegetation Cover in the Arid Savannas of Namibia Using LiDAR Training Data, Machine Learning, and ALOS PALSAR Data

Namibia is a very arid country, which has experienced significant bush encroachment and associated decreased livestock productivity. Therefore, it is essential to monitor bush encroachment and widespread debushing activities, including selective bush thinning and complete bush clearing. The aim of study was to develop a system to map and monitor fractional woody cover (FWC) at national scales (50 m and 75 m resolution) using Synthetic Aperture Radar (SAR) satellite data (Advanced Land Observing Satellite (ALOS) Phased Arrayed L-band Synthetic Aperture Radar (PALSAR) global mosaics, 2009, 2010, 2015, 2016) and ancillary variables (mean annual precipitation—MAP, elevation), with machine learning models that were trained with diverse airborne Light Detection and Ranging (LiDAR) data sets (244,032 ha, 2008–2014). When only the SAR variables were used, an average R2 of 0.65 (RSME = 0.16) was attained. Adding either elevation or MAP, or both ancillary variables, increased the mean R2 to 0.75 (RSME = 0.13), and 0.79 (RSME = 0.12). The inclusion of MAP addressed the overestimation of FWC in very arid areas, but resulted in anomalies in the form of sharp gradients in FWC along a MAP contour which were most likely caused by to the geographic distribution of the LiDAR training data. Additional targeted LiDAR acquisitions could address this issue. This was the first attempt to produce SAR-derived FWC maps for Namibia and the maps contain substantially more detailed spatial information on woody vegetation structure than existing national maps. During the seven-year study period the Shrubland–Woodland Mosaic was the only vegetation structural class that exhibited a regional net gain in FWC of more than 0.2 across 9% (11,906 km2) of its area that may potentially be attributed to bush encroachment. FWC change maps provided regional insights and detailed local patterns related to debushing and regrowth that can inform national rangeland policies and debushing programs.

English

Wabero forest is one of the very few remnant moist evergreen montane forests in Southeast Ethiopia. However, basic data on vegetation structure and composition of the forest that could provide valuable information for possible conservation measures is lacking. The main objective of this study, therefore, was to investigate the woody species composition, vegetation structure and regeneration status of the forest. In the study 30 quadrants of 20 m by 20 m were used for woody species data and 5 m by 5 m for sapling and seedling in a nested form. The sample quadrants were laid down along transects at a distance of 300 m from each other. Diameters at breast height (DBH), basal area, frequency and importance value index were used for analysis of vegetation structure. In the study, a total of 47 woody plant species belonging to 43 genera and 33 families were recorded. The major families were Rubiaceae and Rutaceae each represented by four species followed by Sapindaceae, Moraceae and Oleaceae each represented by three species. The rest of the 28 families were represented by one or two species, only. The mean density of all the woody species recorded in the study site was 21,737 ha-1. Diospyros abyssinica, Podocarpus falcatus, Strychnos mitis, Celtis africana and Coffea arabica were found to be the most dominant and frequent species with the highest importance value index. Results of regeneration status of the forest, which was analyzed by comparing number of seedling and sapling with mature trees, revealed that the forest is under good regeneration status. Therefore, based on the results of the study, awareness creation and implementation of participatory forest management strategy is recommended in order to sustain the forest. &nbsp; Key words: Basal area, diameters at breast height (DBH), importance value index, Montane forest, woody species composition.

Woody plants structure and composition in Burkina Faso Sahel: Case study in Kékénéné village

Understanding woody vegetation composition and structure is important for leading management decisions in the Sahelian vulnerable zones. The objective of the study was to better knowledge woody vegetation structure and richness in natural vegetation and cropland. The study area is Kekenene village located in Soum province, surroundings Djibo in northern Burkina Faso. In total 54 sample plots were surveyed by means of a botanical inventory of woody vegetation species. All trees ≥ 10 cm dbh were measured. The vegetation structure pattern analyzed were diameter at breast height (dbh), basal area, relative dominance, and relative density, Importance Value Index (IVI) and Family Importance Value (FIV). In total 658 trees recorded was belonging to 21 species, 9 families in natural vegetation and 11 species, 5 families in cropland. Tree density was 15.7 stems/ha and 3.7/ha respectively in natural vegetation and cropland. Tree basal area was 0.54 m² ha -1 for cropland and 0.35 m² ha -1 in natural vegetation with a mean dbh of 3.5 cm for the two occupation types. The most importance family according to FIV was Balanitaceae in cropland and Combretaceae in natural vegetation. The Sorensen’ similarity coefficient of family in the two landscapes is lowest than 0.5 which means that the similarities in species family are low between the two occupation types. In natural vegetation, Anogeisus leiocarpus and Balanites aegyptiaca were the most important species in relation to IVI, while in cropland Balanites aegyptiaca, Acacia senegal and Acacia seyal were the most important species. Results reveal an abundance of Balanites aegyptiaca in both cropland and natural vegetation in the study site. Given its high socio-economic value in this region, this tree deserves to be more valued in a perspective of management and sustainable use in Kekenene village. Keywords : Composition and structure, woody species, management, Sahel ecosystems, Burkina Faso.

One savanna, many shapes: How bush control affects the woody layer in the southern Kalahari

Bush thickening (shrub encroachment) is a major ecological and economic threat in southern African savannas. Different types and intensities of bush control (BC) are applied to counteract and mitigate bush thickening. However, woody vegetation response to BC and possible ecological side effects can be manifold. Land users therefore require solid knowledge about the associated structural and compositional changes, helping to apply an informed BC strategy that preserves multiple ecosystem services and functions. The present study addresses this need in a South African thornbush-type savanna. We sampled 41 rangeland sites with a known history of BC in comparison to benchmark conditions. The BC treatments included a selective and non-selective arboricide application and a selective stem burning. We identified each woody species in belt transects and measured the size and canopy of all individuals. The data were used to calculate measures of diversity, cover and density and to describe the population structure of key species. Marked differences in woody species composition and abundance patterns as well as significant alterations of the horizontal and vertical woody vegetation structure clearly reflected the intensity and level of selectivity with which BC had been conducted. While population trends displayed regeneration of key species, important structural elements (large mature trees) were often at risk of being lost from the savanna ecosystem. Results suggest varying degrees of ecosystem functional integrity following the BC treatments. It is concluded that selective BC treatments should be preferred as they allow to create open and well-structured savannas in benefit of the stability and biodiversity of the system. Yet, for improved predictions further research is needed into species-specific population dynamics and trait-related plant–plant interactions. In addition, there is still uncertainty about possible long-term ecological effects associated with the use of arboricides in this type of savanna, which should receive special attention in future research.

Cross-Border Comparison of Non-Forest Woody Vegetation in the White Carpathians (Central Europe) Over Last 65 Years

Abstract Landscape structure is determined by human activities and natural processes. Despite both influences are described in many studies, there remains still question, how the landscape structure reflects the individual socio-economic predictors. To answer this question we compared landscape structure, with emphasis on non-forest woody vegetation, of two states, however, with common socio-economic and political history. Non-forest woody vegetation represents characteristic feature in rural landscape, which increases water retention, biodiversity and bio-migration using green structures. In our study we supposed, that non-forest woody vegetation will have high sensitivity to societal changes and nature conservation measures. On an example of border region in former Czechoslovakia we compared three classes of non-forest woody vegetation (solitaires, patches and linear elements) in three time horizons (1950, 1986, 2011). The most significant differences in spatial structure of non-forest woody vegetation between countries were in the number and area of solitaires, which decreased during the entire period. However, the largest solitaire decrease was in 1950-1986, mainly in correspondence with socialist collective farming. Moreover, the decrease was higher in the Slovak part compared to the Czech part. The primary reason for this was the removal of non-forest woody vegetation on one side and the joining crowns into bigger patches on the other side. The current trend of increasing area of patch and linear elements is related to natural succession. We assume that the main drivers of different development in non-forest woody vegetation in the border region after the split of Czechoslovakia were different management measures applied in nature and landscape conservation and social development.

Annual continuous fields of woody vegetation structure in the Lower Mekong region from 2000‐2017 Landsat time-series

Spatially and temporally consistent vegetation structure time-series have great potential to improve the capacity for national land cover monitoring, to reduce latency and cost of international reporting, and to harmonize regional land cover characterizations. Here we present a semi-automatic, operational algorithm for mapping and monitoring of woody vegetation canopy cover and height at a regional scale using freely available Landsat time-series data. The presented algorithm employs automatic data processing and mapping using a set of lidar-based vegetation structure prediction models. Changes in vegetation cover are detected separately and integrated into the structure time-series. Sample-based validation and inter-comparison with existing datasets demonstrates the spatial and temporal consistency of our regional data time-series. The dataset reliably reflects changes in tree cover (tree cover loss user's accuracy of 0.84 and producer's accuracy of 0.75) and can serve as a tool to map annual forest extent (user's accuracy of 0.98 and producer's accuracy of 0.81 for 10% canopy cover threshold to define the forest class). The tree height estimates are consistent with a GLAS-based global map (mean average error of 3.7 m, the correlation coefficient of 0.92 and the R2 of 0.85). The algorithm was prototyped within the Lower Mekong region where it revealed an intensive woody vegetation dynamic. Of the year 2000 forest area (defined using canopy cover threshold of 10% and tree height threshold of 5 m), 9.4% was deforested by the year 2017, and 16.6% was affected by stand-replacement disturbance followed by reforestation. The average annual area of stand-level forest disturbance within the region was 2.34 Mha, and increased by 34% from 2001 (1.85 Mha) to 2017 (2.48 Mha). Total forest area decreased by 6.2% within the region, and 11.1% of year 2000 primary forest area was lost by 2017. At the national level, Cambodia demonstrated the highest rate of deforestation, with a net forest area loss of 22.5%. We estimated that 21.3% of 2017 forest cover had an age of 17 years or less, illustrating the intensive forest land uses within the region. The time-series product is suitable for mapping annual land cover and inter-annual land cover change using customized class definitions. The regionally-consistent data are publicly available for download (https://glad.umd.edu/), and online analysis (https://rlcms-servir.adpc.net/en/forest-monitor/), and serve as an input to the SERVIR-Mekong Regional Land Cover Monitoring System.

Predictors of conservation value of Turkish cemeteries: A case study using orchids

In the face of worldwide habitat loss, the role of human-shaped habitats in conserving biodiversity is becoming increasingly important. Due to their special cultural role, cemeteries can preserve parts of the native vegetation when the surrounding landscape becomes degraded. However, these special refuges are threatened by human encroachment and changing management practices. The aim of this study was to understand how urbanization affects the conservation value of cemeteries, indicated by orchids as flagship species for biodiversity conservation. We analyzed species richness, abundance and the presence of threatened orchid taxa in cemeteries from 631 differently sized Turkish settlements along an urban-rural gradient. To understand driving patterns determining the conservation value, we performed detailed characterization of 288 cemeteries in terms of woody vegetation (tree cover and proportion of native trees) and overall structure (age, density and type of graves). Conservation value was highest in rural cemeteries. Rural cemeteries were smaller, contained more traditional and less densely situated graves, but their woody vegetation was similar to urban cemeteries. The proportion of native trees was positively related to species richness, abundance and presence of threatened orchid taxa, after taking into account area, altitude and geographical location of cemeteries. In addition, cemetery structure (age and density of graves) predicted species richness. Our results indicate that urbanization and modern changes in human activity have a strong impact on the conservation value of Turkish cemeteries. Practices maintaining traditional burial habits and environment-friendly management of cemeteries deserve more moral and financial support.

Temperature influences resource use by chestnut‐bellied scaled quail

AbstractAnimals use physiological and behavioral adaptations to maintain constant body temperatures when environmental temperatures are outside of their thermoneutral zone. We define the temperature suitability bounds as the range of temperatures above and below which animals avoid locations because of unfavorable thermal conditions. Temperatures outside the temperature suitability bounds may trigger behavioral responses such as movement to cooler locations. We tested the hypothesis that temperature during late April to August influences resource selection using chestnut‐bellied scaled quail (Callipepla squamata castanogastris) as our study species. We estimated temperature suitability bounds for scaled quail and tested the prediction that ground surface temperature is a better predictor of habitat space use than black globe temperature. We compared models containing ground surface temperature and woody vegetation structure variables to test the hypothesis that including woody vegetation variables improves prediction of relative probability of use. We trapped scaled quail at five different locations in southern Texas. We located quail fitted with necklace‐style transmitters three times/week during 2013–2014. We measured ground surface and black globe temperatures at locations used by scaled quail and at random locations. We estimated percent canopy cover of cacti, subshrubs, and woody plants using 20 × 50 cm Daubenmire frames at each used and random location. We also estimated height and vertical obstruction of woody vegetation. Temperature suitability bounds of scaled were 24–43°C for the ground surface and 23–39°C for black globes. Ground surface temperature was a better predictor of relative probability of use than black globe temperature. Ground surface temperature during the warmest time of day (early afternoon, 13:30–17:29) decreased with increasing vertical obstruction after accounting for the influence of other structural variables. The best model for predicting relative probability of use by scaled quail during the warmest time of day included ground surface temperature and vertical obstruction. Use of microsites where vegetation structure is conducive to cooler temperatures is an important driver of resource selection by scaled quail during the warmest time of day in southern Texas, but availability of thermal refugia appears to be limited.

Woody Species Composition, Diversity and Vegetation Structure of Dry Afromontane Forest, Ethiopia

Woody Species Composition, Diversity and Vegetation Structure of Dry Afromontane Forest, Ethiopia