Eastern Aspects Research Articles

Ecological Attributes of the Shrubby Community of Sotol (Dasylirion leiophyllum) in the Chihuahuan Desert, Mexico

Sotol (Dasylirion leiophyllum) is a shrubby species that grows in the Chihuahuan Desert. Sotol plants are commonly used to produce an alcoholic beverage, also known as “sotol”. A study was carried out to assess the composition and structure of shrubby communities where sotol inhabits in northern Mexico. The importance value index (IVI), diversity indexes, and structural attributes of the sotol community were estimated. Furthermore, a principal component and a cluster analysis were conducted in order to identify possible associations of species along the sotol distribution area. A total of 10,273 plants belonging to 17 families and 46 species were recorded, where the Agave lechuguilla and Tiquilia greggi were the most abundant species. Higher abundances of sotol and higher diversity indexes were observed in hillside areas and eastern aspects. The multivariate analyses revealed five shrubby groups in the distribution area of sotol, which grows in valleys, hillsides, and also on the top of mountains. The main communities found where sotol grows are rosetophyllous, microphyllous, and mesquite communities, and also, in higher altitudes, sotol is associated with oak species. This information is not only useful for a better species knowledge, but also for the protection of shrubby communities where Dasylirion leiophyllum inhabits.

Life history and bionomics of Glycobius speciosus (Coleoptera: Cerambycidae: Cerambycinae: Clytini).

Glycobius speciosus (Say) was studied in New York State to elucidate poorly known aspects of its biology. Head capsule size from excavated larvae coupled with gallery lengths measured at the time of excavation was used to characterize larval development. Partial life tables indicated nearly 20% of G. speciosus survive to adulthood. Larvae experienced 30% of their mortality during early development, 27% during mid-larval development, and 43% during late larval development. Predation by hairy woodpeckers, Dryobates villosus (Linnaeus) (Piciformes: Picidae), the only unambiguous source of mortality, accounted for 43% mortality in naturally infested trees located and followed 2004-2009, and 74% late instar mortality. One parasitoid, Dolichomitus irritator (Fabricius) (Hymenoptera: Ichneumonidae), was recovered from a single larva. Beetles emerged between 316 accumulated DD (base 10 °C) and 648 DD. Males emerged prior to, or simultaneously with, females and lived longer. Female fecundity averaged 41.3 ± 6 eggs. Larval eclosion occurred 7-10 days after oviposition. Non-functional ovipositors observed in 16% of females represented an appreciable reproductive loss. In 77% of infested trees 1 oviposition site was located and in 70% of oviposition sites examined only 1 or 2 larvae successfully eclosed, penetrated the bark to the phloem-xylem interface, and began feeding. Beetles preferred southern and eastern aspects for oviposition which occurred preferentially on the lower bole (<20 cm). Male beetles had longer and wider antennae than females, pronotal pits containing gland pores, and a straight to concave posterior margin of the terminal sternite compared to the more rounded margin of females.

Topographic information improves simulated patterns of post-fire conifer regeneration in the southwest United States.

The western United States is projected to experience more frequent and severe wildfires in the future due to drier and hotter climate conditions, exacerbating destructive wildfire impacts on forest ecosystems such as tree mortality and unsuccessful post-fire regeneration. While empirical studies have revealed strong relationships between topographical information and plant regeneration, ecological processes in ecosystem models have either not fully addressed topography-mediated effects on the probability of plant regeneration, or the probability is only controlled by climate-related factors, for example, water and light stresses. In this study, we incorporated seedling survival data based on a planting experiment in the footprint of the 2011 Las Conchas Fire into the Photosynthesis and EvapoTranspiration (PnET) extension of the LANDIS-II model by adding topographic and an additional climatic variable to the probability of regeneration. The modified algorithm included topographic parameters such as heat load index and ground slope and spring precipitation. We ran simulations on the Las Conchas Fire landscape for 2012-2099 using observed and projected climate data (i.e., Representative Concentration Pathway 4.5 and 8.5). Our modification significantly reduced the number of regeneration events of three common southwestern conifer tree species (piñon, ponderosa pine, and Douglas-fir), leading to decreases in aboveground biomass, regardless of climate scenario. The modified algorithm decreased regeneration at higher elevations and increased regeneration at lower elevations relative to the original algorithm. Regenerations of three species also decreased in eastern aspects. Our findings suggest that ecosystem models may overestimate post-fire regeneration events in the southwest United States. To better represent regeneration processes following wildfire, ecosystem models need refinement to better account for the range of factors that influence tree seedling establishment. This will improve model utility for projecting the combined effects of climate and wildfire on tree species distributions.

MOSSES OF THE WESTERN PART OF THE CHUKCHI HIGHLANDS. 3. INTERDEPENDENCE OF PERCENT COVER VALUES OF MOSSES AND VASCULAR PLANTS

In previous publications (Kholod, Afonina, 2023a, b) the dependences of the number of moss species and the values of moss percent cover in the western part of the Chukchi Highlands on a number of abiotic factors were considered. This article discusses the interdependence of the percent cover values of mosses and vascular plants in this area. On the slopes of most aspects, an increase in the percent cover values of vascular plants to a value of 65–75% is accompanied by an increase in the percent cover values of mosses (up to 40–70%), which decreases with a further increase in the percent cover values of vascular plants. Two groups of bryocenotypes, one of them being formed on dry, relatively steep slopes of the southern and western aspects with rapidly descending snow, and the other on wet, snow-covered gentle slopes of the northern and eastern aspects, characterize 2 types of natural environments of the Pleistocene-Holocene: cooling with active freezing of loose strata of slopes, and warming with intense permafrost melting and activation of slope processes, respectively. The linear relationship between the values of the percent cover of vascular plants and mosses, on the one hand, and the area of unpaved soil, on the other, is considered as a model of the settlement of soils by mosses during the transition from cold climatic epochs to warm ones. In such transitional epochs, vascular plants have an advantage in the percent cover values at the initial stage, then, with the growth of mosses, the increase in the percent cover values of vascular plants slows down, which is a manifestation of the regulatory influence of mosses through the availability of accessible water and a number of other parameters.

Population decline in a Pleistocene refugium: Stepwise, drought-related dieback of a South Australian eucalypt

Refugia can facilitate the persistence of species under long-term environmental change, but it is not clear if Pleistocene refugia will remain functional as anthropogenic climate change progresses. Dieback in populations restricted to refugia therefore raises concerns about their long-term persistence. Using repeat field surveys, we investigate dieback in an isolated population of Eucalyptus macrorhyncha during two droughts and discuss prospects for its continued persistence in a Pleistocene refugium. We first confirm that the Clare Valley in South Australia has constituted a long-term refugium for the species, with the population being genetically highly distinct from other conspecific populations. However, the population lost >40 % of individuals and biomass through the droughts, with mortality being just below 20 % after the Millennium Drought (2000–2009) and almost 25 % after the Big Dry (2017–2019). The best predictors of mortality differed after each drought. While north-facing aspect of a sampling location was significant positive predictor after both droughts, biomass density and slope were significant negative predictors only after the Millennium Drought, and distance to the north-west corner of the population, which intercepts hot, dry winds, was a significant positive predictor after the Big Dry only. This suggests that more marginal sites with low biomass and sites located on flat plateaus were more vulnerable initially, but that heat-stress was an important driver of dieback during the Big Dry. Therefore, the causative drivers of dieback may change during population decline. Regeneration occurred predominantly on southern and eastern aspects, which would receive the least solar radiation. While this refugial population is experiencing severe decline, some gullies with lower solar radiation appear to support relatively healthy, regenerating stands of red stringybark, providing hope for persistence in small pockets. Monitoring and managing these pockets during future droughts will be essential to ensure the persistence of this isolated and genetically unique population.

Towards an integrated phosphorus, carbon and nitrogen cycling model for topographically diverse grasslands

Contemporary science on how livestock influence nutrient cycling in grazing systems is limited, particularly in topographically complex (i.e., slopes and aspects) hill country landscapes. Prominent slope and aspect variation affects primary production, animal behaviour and nutrient return. Here, we embed recent scientific advancements in nutrient dynamics across complex landscapes to (1) set up a soil organic carbon (SOC) saturation function to an existing SOC and total soil phosphorus (TSP) model (Bilotto et al. J N Z Grassl 81:171–178, 2019. https://doi.org/10.33584/jnzg.2019.81.397), (2) include total soil nitrogen (TSN) dynamics, and (3) establish if the model (herein the Grass-NEXT model) can simulate the spatial and temporal changes of TSP, SOC and TSN in hill country. A long-term P fertiliser experiment with contrasting different P fertilisation levels and associated sheep stocking regimes (herein, ‘farmlets’) was used for model testing. The Grass-NEXT model predicted TSP and SOC stocks with strong accuracy and precision (model performance), and TSN with a moderate performance across farmlets [Concordance Correlation Coefficient (CCC), 0.75, 0.72 and 0.49, respectively]. Grass-NEXT model simulated TSP, SOC and TSN distribution with moderate/strong performance across slopes (CCC, 0.94, 0.80 and 0.70) and aspects (CCC, 0.83, 0.67 and 0.51). Consistent with observed data, modelled changes in TSP and TSN were greater on low slopes and eastern aspects, but no clear pattern was observed for SOC stocks. The Grass-NEXT model provides an intuitive research tool for exploring management options for increasing SOC and TSN, as well as an instrument for monitoring and reporting on nutrient dynamics in complex landscapes.

Fire Drivers Affecting Forest Fire Occurrences in the Tropical Mixed Broad-leaved Forests of Nepal

Forest fires triggered by various natural and anthropogenic drivers are increasing and threatening forest ecosystems across the globe. In Nepal, the high value Tropical Mixed Broad-leaved Forests are prone to fire caused by both natural and anthropogenic drivers. Thus, understanding fire drivers and their effect is important for the sustainable forest fire management. However, the preceding studies on forest specific fire drivers and their effect are limited. This research has identified the fire drivers and assessed their effect to fire occurrences in the Tropical Mixed Broad-leaved Forests of Nawalparasi District, Nepal. Fire drivers were identified and prioritized by participatory approaches. The fire incidences and burnt areas were obtained from the MODIS fire data (2001–2017). The results revealed altogether 20 drivers including eight natural and 12 anthropogenic. Based on the public perception and magnitude of forest fire, among the natural drivers, temperature, precipitation, forest fuel, aspect, elevation and slope were the major drivers. Likewise, among the anthropogenic drivers, forest distance from roads and settlements showed significant effect. The natural drivers, ambient temperature &gt;30ºC and annual precipitation &lt;2400 mm, revealed signi-ficant impacts on forest fire. Likewise, forests situated at lower elevation (&lt;500 m), and southern and eastern aspects were highly vulnerable to fire. Considering anthropogenic drivers, forest lying within 500 m from the roads and settlements were highly vulnerable to fire. Among the forest types, the Hill Sal Forest was more affected. Future strategies should address the major fire drivers, construction of adequate fire lines and conservation ponds for the sustainable forest management.

Soil moisture change analysis under watershed management practice using in situ and remote sensing data in a paired watershed.

Soil moisture, vegetation cover, and land surface temperature are vital variables in water-energy balance, eco-hydrological processes, and water resources management, which can be influenced by watershed management activities. This research focused on the spatial and temporal variability of soil moisture, vegetation cover, land surface temperature, and Temperature-Vegetation Dryness Index (TVDI) under a biological watershed management practice in the Taleghan paired watershed, namely, treated (TW) and control watersheds (CW), in Alborz province, Iran. In this research, along with the remote sensing techniques, the soil moisture and vegetation cover data were measured and statistically analyzed in the three aspects of both TW and CW during a growth period from May to October 2017. The results indicated that soil moisture, vegetation cover, and land surface temperature values in the paired watershed were significantly different at the 0.01 level during the study period. The increased vegetation cover in the TW had an inverse effect on the land surface temperature and TVDI, while directly impacted the soil moisture content. The average TVDI in the CW was 0.83, while this index was found to be 0.69 in the TW. Unlike the vegetation cover and soil moisture, the results revealed that the southern aspects had the highest TVDI and land surface temperature compared to the northern and eastern aspects of both watersheds. However, the increased vegetation cover as a biological watershed management activity in the steep terrain and mountainous areas of TW led to an increased soil moisture and a decreased land surface temperature and soil dryness. As a result, decreasing soil dryness in the TW can exert vital controls on the water resources and increasing water availability. In the arid and semiarid countries such as Iran, a proper watershed management activity can effectively increase soil moisture and water availability in the watersheds. In particular, the vegetation cover protection and biological practices can be considered as practical solutions in the rehabilitation of exhausted watersheds in arid and semiarid environments.

Foraging habitat selection of overwintering Black-necked Cranes in the farming area surrounding the Caohai Wetland, Guizhou Province, China

BackgroundUnderstanding how overwintering birds choose foraging habitats is very important for conservation management. The overwintering Black-necked Crane (Grus nigricollis) feeds on crop remains in farmlands; thus, reasonable conservation management of this type of farmland that surrounds wetlands is critical for the overwintering populations of the Black-necked Crane; however, it is not clear how the Black-necked Crane chooses the foraging land in the farmland.MethodsA thorough field positioning survey of all foraging sites in farmland areas around the Caohai Wetland and a sampling analysis of habitat selection by the Black-necked Crane were conducted during the winters from 2016‒2017 and 2017‒2018.ResultsMultiple factors contributed to the selection of foraging habitat in farmlands, i.e., food factors (crop remains and tillage methods) > human disturbance factors (distance to road and settlement) > topography factors (slope aspect), listed according to the strength of influence. Additionally, Black-necked Cranes tend to choose farmland sites where there was no machine tillage, the crop remains were > 500 g/m2, the distance to residences ranged from 100 to 500 m, the distance to roads ranged from 50 to 100 m, and the slopes exhibited western or eastern aspects. As the winters progressed, the volume of the edible crop remains declined, and the influences of the other main factors also changed, i.e., the factors of human disturbance (distance to road and settlement) became less important, while the effect of the food factor (crop remains) was strengthened. Thus, the foraging sites near the road became more important.ConclusionThe farming area surrounding the Caohai Wetland is very important for the overwintering Black-necked Crane. Food factors and human disturbance factors are the main factors that influence the choice of feeding ground.

Extreme drought affects the productivity, but not the composition, of a desert plant community in Central Asia differentially across microtopographies

Extreme climatic conditions are major drivers of ecosystem function and dynamics and their frequency is increasing under climate change. Climatic conditions interact with local microtopography, which might either buffer or exacerbate the degree of climatic stress. Here we sought to understand how extremely dry growing seasons affected the composition and productivity of desert ephemeral communities growing in sand dunes from the Gurbantunggut desert in Central Asia, and to which extent did microtopography modulate the response. We set up a rainfall manipulation study on four sand dune microtopographies and, during two consecutive years, we measured soil moisture, nutrients and texture, ephemeral layer composition, plant phenology, biomass accumulation and biomass allocation patterns for the dominant species. We observed significant biomass reductions during the extreme drought but plant community richness and composition were not affected, indicating that the composition of the ephemeral layer in this desert ecosystem may resist under extreme conditions. Additionally, extreme drought increased biomass allocation to reproductive organs of the dominant species. There were also significant microtopographic effects as the sensitivity of biomass to drought in western aspects was larger than in eastern aspects. Our results indicate that previously overlooked microtopographical differences may mediate the impact of climate change on plant communities.

Threats and Conservation of Paris polyphylla: Vulnerable Medicinal Plant in Panchase Protected Forest, Nepal

Government of Nepal has enlisted Paris polyphylla as the priority medicinal and aromatic plant (MAPs) for the economic development of the country due to its high market price and demand. But in Panchase Protected Forest (PPF) its value is not well recognized. Therefore, this study aimed to explore the distribution of the plant, assess threats and interventions for conservation and promotion in Bhadaure Tamagi area of Kaski district. Participatory resource mapping, semi-structured questionnaire and key informant survey were carried out for data collection. The plant was distributed at nine different patches of the forest at moist, fertile, and sloppy sites in Northern and Eastern aspects, and spotted only at two patches. Among 10 threat factors, illegal collection with Relative Threat Factor Severity Index (RTFSI) value of 0.90 was the major threat to the plant, and forest fire with value of 0.25 was the least impacting threat. Poor management and institutional factors were not understood by local people directly. Though the plant has high market value, only 6% of the locals used the plant for direct income whereas the rest used for the household purpose as they have no idea of the market. It is recommended to empower and support local people for commercial cultivation and trade, sustainable harvesting techniques, and to bring all the concerned stakeholders of PPF together to work effectively to conserve and promote this wonder herb.

Modelling long-term changes in soil phosphorus and carbon under contrasting fertiliser and grazing management in New Zealand hill country

Soil carbon (C) stocks under permanent New Zealand pastures vary with slope and aspect due to differences in primary production, animal behaviour and nutrient return. An existing nutrient transfer model was extended using a web-based, general-purpose modelling tool to simulate long-term changes in soil phosphorus (P) and C in hill country under contrasting fertiliser and sheep stocking regimes. Three self-contained farmlets were examined: no P applied; 125 kg single superphosphate (SSP)/ha/year; and 375 kg SSP/ha/year, since 1980. The refined spatial model was able to simulate P and C distribution with varying slopes and aspects. For example, the mean annual changes in soil P and C were greater on low slopes and eastern aspects than on the other two slope and aspect positions, consistent with observed changes in these nutrients. However, the model overestimated changes in soil C, which highlighted both gaps in current knowledge and key factors influencing change in soil C stocks. Understanding the spatial patterns of soil C across the landscape will be critical in the design of soil C monitoring regimes, should soil C stocks be considered at a national level as a sink or source of CO2 emissions.

Cirques in the Sierra de Guadarrama and7 Somosierra Mountains (Iberian Central System): Shape, size and controlling factors

The Guadarrama and Somosierra mountain ranges form the eastern sector of the Iberian Central System and hosted numerous glaciers during the Late Pleistocene (MIS2). Glaciation was of low intensity with glaciers of small sizes, strongly controlled by the climatic context and the topography. This study analyses the shape, size, distribution and location of 96 cirques existing in these mountain ranges. In addition to the standard morphometric parameters and controlling factors (altitude, aspect and lithology) used in most studies, additional factors were considered here in relation to the pre-glacial relief and fracture network. The data were obtained and processed using ArcGIS 10.4 and relations between the parameters and controlling factors were evaluated using statistical methods. The results indicate that most are simple cirques, tending to isometry, with low vertical incision capacity, considerable variation in size and predominantly east-facing. In the context of the Iberian Peninsula and other European mountains, these cirques are among the most isometric, the lowest in height and present the least overdeepening. The development of these cirques has generally been the result of random combination of various factors. Thus: (i) the largest cirques are located at intermediate altitudes, with the headwall located on the main divides, at former torrential valley heads or at the headwalls of fracture corridor valleys, and are north-facing; (ii) the longest cirques are located at former torrential valley heads, on metamorphic bedrock (i.e. schists, slates) and on uniform slopes. Finally, the prevailing eastern aspects are explained by topoclimatic factors and are in agreement with previous studies, which have proposed a Circulation Weather Type (CWT) model throughout the Iberian Peninsula during the Last Glacial Period, similar to its current configuration.

Assessing revegetation effectiveness on an extremely degraded grassland, southern Qinghai-Tibetan Plateau, using terrestrial LiDAR and field data

The Qinghai-Tibetan Plateau (QTP) is one of the most difficult eco-regions for revegetation on degraded grassland because of its harsh environment. Micro-topography could affect habitat conditions important to ecological restoration on sandy land; however, the interaction between revegetation and micro-topography has been rarely reported on sand dunes of the QTP. Here, we quantified vegetation (including coverage, leaf area index (LAI), height, and crown diameter) and micro-topographic parameters (including elevation, slope, and aspect) to assess the effects of topography on revegetation using field observation data during 2008–2017 and terrestrial laser scanning (TLS) in 2017. The results showed that: 1) the tested plant species for revegetation has changed significantly from 2008 to 2017, and the current dominant plant species were mainly introduced from north China, including Hedysarum scoparium, H. fruticosum, and Artemisia sphaerocephala. 2) The effectiveness of revegetation has been improved remarkably over the past ten years. The vegetation coverage varies from 68.4% to 80.5% at four big quadrats of 20 m × 20 m, while the LAI value varies from 2.30 to 3.27, the shrub height ranges from 1.12 m to 7.57 m, and the crown diameter ranges from 0.24 m to 6.96 m. 3) A total of 153 shrubs were extracted in these four quadrats using TLS; and 56.9%, 21.6% and 10.5% of them are distributed on the southeastern, southern, and eastern aspects, respectively. The height and crown diameter of individual shrubs are significantly correlated with the local slope (p < 0.05) of which could affect the distribution of artificial seeding. These results suggest that aspect and slope are two key limiting factors for revegetation, and the habitat conditions on the southeastern and eastern aspects favor revegetation on valley-slope sand dunes. These findings provide a useful guidance in developing an integrated ecological restoration plan for sand dunes and selecting the best practice management of ecosystem services on degraded grassland on the QTP.

Distribution, biology, morphology and damage of Cinara cedri Mimeur, 1936 (Hemiptera: Aphididae) in the Isparta Regional Forest Directorate

DOI : 10.26650/forestist.2019.346284 In 2015-2016, a study was performed examining the distribution, colony dispersion in tree canopies, occurrence rate in shoots at different ages, morphology, and the damage of the cedar aphid (Cinara cedri Mimeur 1936) (Hemiptera: Aphididae) This study was completed alongside biological observations in the Isparta Regional Forest Directorate. This study was conducted across 46 sites at an elevation of 820-1738 meter (m) and the distribution of this species was determined by a survey. Compared to other sites, the Cinara cedri (C. cedri) population was found to be higher in 10 sites with young stands with an average height of 1000-1200 m. These sites were established through plantation. Colonies were typically observed on the shoots from the previous year and on branch axils. They were found to feed on shoot tips and trunks of young trees and preferred shoots with a diameter of 1.0-1.5 centimeter (cm) on the southern and eastern aspects of the trees. It was observed that C. cedri mostly fed on shoots of the previous year, which caused the needles to dry and turn red. Damage was observed especially on young trees from which the dried needles fell and defoliation was concentrated particularly on the shoot tips and tops of the trees. It was found that honeydew was secreted by those insects fed with sap, and this secretion then covered the needles, shoots and branches, resulting in fumagine. The populations overwintered as eggs and then nymphs hatched during the first week of April. The adult stage was reached after completing four nymph periods over a time span of between one week and 10 days. These adults then reproduced parthenogenetically, with winged viviparous individuals appearing between May and June, and oviparous emerging in October. The final stage of the cycle was a period of mating and then egg-laying.

Ландшафтное картографирование бассейна р. Майма (Русский Алтай)

The analysis of landscape differentiation of the low-mountain Maima basin was performed due to the field studies for different periods as well as the remote sensing data. The formation of modern landscapes of the basin depends on regional features related to geographical location of landscapes on the periphery of the mountain region (mainly in its low-mountain part) and local factors as well. Structural-lithological and geomorphological heterogeneity, high-altitude along with climatic background parameters determine the development of the landscape structure of the territory. The basin map represents the peculiarities of current landscapes arrangement at the local level (groups of stows, their spatial modifications) and atregional one (subtypes of landscapes). In the forest-steppe area, slopes (4-10 and 10-20) of the southern, western and eastern aspects with grass-forb real and steppe meadows dominate. Sub-taiga landscapes are represented by terraced slopes (10-20) of northern and northeastern aspects with birch-pine and pine-birch forests. Among the chern-taiga landscapes, the slopes (10-20) of the eastern and western aspects with birch-aspen-fir forests prevail. Modified and transformed landscapes occupy about 30 % of the basin area due to the largest agglomeration (Gorno- Altaisk, Maima and Kyzyl-Ozek) in the Russian Altai. Secondary grasslands occupy 20 % of the basin area that is mainly related with anthropogenic modifications (deforestation, grasslands). The share of perennial plantations and arable land accounts for 2 %; built – up areas-about 4 %.

Growth and Survival of Endemic Cacti under Different Substrate Types and Sun Exposures for Their Optimal Establishment in Northeastern Mexico

Cactaceae are subject to strong anthropogenic pressure, which motivates the search of strategies for its conservation. This paper aimed to evaluate the survival and growth of eight native species from northeastern Mexico, in order to propose their in-situ conservation, applying three substrates (perlite/peat-moss, zeolite/peat-moss and natural soil), in two sun exposures (west and east). The variability of both survival and growth resulted dependent on substrate type and sun exposure. Astrophytum myriostigma presented higher diameter at eastern aspects (51.20 and 42.63 mm on zeolite/peat-moss and perlite/peat-moss, respectively), and the higher heights were also registered at eastern aspects, with Sclerocactus scheeri (7.38.cm on perlite/peat-moss and 6.98 cm on natural soil) and A. myriostigma (6.8 cm on zeolite/peat-moss and 6.08 cm on perlite/peat-moss). As for survival, the highest value (100%) was recorded with the treatments of West-Zeolite/peat-moss and East-Perlite/peat-moss, in six of the eight species evaluated (A. myriostigma, Acharagma roseana, Escobaria dasyacantha, S. scheeri and Mammillaria prolifera), while the lowest value (0%) was recorded with M. plumosa in the three western combinations. The best growth and survival responses were observed in A. myriostigma and S. scheeri under east exposure and zeolite, being the best combination, to be considered for their optimal establishment.

Terrain encountered along the browsing path of Tragelaphus strepsiceros in the Musina Nature Reserve, Limpopo Province

Despite the wide distribution of the Tragelaphus strepsiceros (greater kudu) in the mopane woodland, there is still limited information on the influence of terrain on the browsing path of the greater kudu. There is also a lack of information on terrain associated with the browsing paths of male and female greater kudu. This study was conducted at Musina Nature Reserve from June 2012 to December 2013. Backtracking, which is a post-browsing method, was used to capture the movement of browsing greater kudu. This method entails the direct and indirect observation of the greater kudu at the point of browsing along a browsing path. The different terrains on which the greater kudu moved while browsing are taken as a percentage of the total browsing path. Areas frequented by male and female greater kudu were compared using t-test (Paired Two Sample for Means) and Spearman Correlation Coefficient analysis. Results indicated that the browsing greater kudu highly frequented the plains (72%) and flat areas (95%), particularly during the late wet season. During the pre-rain flush season, the browsing greater kudu spent most of the time (59%) walking on soil substrate. The eastern (50%) and northern (50%) aspects of hills were equally frequented during the late wet season. There were no significant gender differences on the preferred terrain. It is concluded that the browsing path of the greater kudu is largely influenced by the availability of browse, safety and conducive local weather conditions.

Quantitative assessment of pedodiversity and soil erosion within a karst sinkhole in the dry steppe subzone

A detailed study of the soil cover of a sinkhole (300 m2) in the dry steppe landscape of the Bogdinsk–Baskunchak Natural Reserve in Astrakhan oblast has been performed, and the factors of its differentiation have been analyzed. The indices of pedodiversity have been calculated and compared for karst sinkholes in the dry steppe and northern taiga landscapes. Quantitative parameters of the lateral migration of solid soil substances on the slopes of the sinkhole have been determined. The rate of soil erosion decreases from the slope of southern aspect to the slopes of western, northern, and eastern aspects. On the average, it is estimated at 0.4 mm/yr. The average rate of accumulation of solid substances on the lower parts of the slopes and in the bottom of the sinkhole reaches 0.74 mm/yr. A comparative analysis of the soil properties attests to their dependence on the particular position of a given soil within the sinkhole. Downward the slopes of the sinkhole, full-profile brown arid soils (Cambic Calcisols) are replaced by sierozem-like soils (Haplic Calcisols), light-humus poorly developed soils (Luvisols), lithozems (Leptosols), and stratified soils (stratozems, or Colluvic Regosols). The soils within the upper ring-shape soil microzone are more diverse and contrasting with respect to their morphological, physical, chemical, and physicochemical properties. The degree of soil contrasts decreases down the slopes of the sinkhole towards its bottom. The studied sinkhole is characterized by considerable pedodiversity. Quantitative parameters of pedodiversity for the sinkhole in the dry steppe zone are higher than those form the sinkholes in the northern taiga zone.

Mapping fire severity and fire extent in forest in Victoria for ecological and fuel outcomes

SummaryThis study shows how high‐resolution (~15 cm) simultaneous colour and infra‐red digital aerial photography can be used to map both fire severity and, particularly, fire extent, in forest in south‐eastern Australia. The results show that this methodology is capable of detecting and mapping burnt and unburnt edges under unaffected forest canopy (i.e. still green) – that is, revealing the mosaic of burnt and unburnt areas that often result from planned landscape burning under mild weather conditions (i.e. with little of the brownish canopy scorch that results from more intense bushfires). This has important implications for both fuel management and ecology. It can answer the basic questions of fire and biodiversity managers following planned burning –’how much of the planned area burnt, and, within the burnt area, what aspects were burnt, and how hot did they burn?’ The analysis of fire extent by aspect showed that about 80% of southern and eastern aspects remained unburnt during broadscale autumn prescribed burning, with many of these moister aspects potentially providing longer unburnt refuges over multiple burn rotations. The fire severity and extent mapping products, produced using the methodology outlined in this study, have the potential to substantially increase the understanding of the ecological and fuel outcomes of landscape‐scale autumn prescribed burning.