Southwest Aspects Research Articles

Biophysical characteristics, distribution and conservation challenges of critically endangered Bhutan poppy (Papaver bhutanicum) in Jigme Dorji National Park, Bhutan

AbstractThe occurrence of certain rare plant species in specific ecological habitats is intricately linked to a myriad of environmental conditions, encompassing both biotic and abiotic factors. The prioritisation of monitoring efforts becomes more impactful when conservationists possess a comprehensive understanding of the ecology and distribution of rare species within their designated habitats and across the entire range of the species. In September 2023, a study was conducted in Jigme Dorji National Park to assess the ecology, distribution and threats to the critically endangered Bhutan poppy. This survey, employing random sampling, covered approximately 87 ha across Tshophu, Tshophu base and Jichudrakey base in Soe Gewog and analysed 202 2 × 2 m plots. The survey revealed 57 plant species from 24 families, with Asteraceae (17.5%) and Papaveraceae (12.3%) dominating. Notably, 46% of families comprised a single species, and significant species richness differences were observed between Tshophu, Tshophu base and Jichudrakey base. Correlations between species richness and environmental variables, including slope, rock cover (%), bare soil cover (%) and herb cover (%), were identified as significant. The Bhutan poppy was positively and significantly associated with the southwest aspect, occupying 59% of surveyed plots. Species distribution modelling predicted a distribution area of approximately 37.29 square kilometres within the national park. However, future climate scenarios indicated a significant shift in the distribution of the Bhutan poppy. By 2041–2060, there is an anticipated decrease of 33% in its distribution area, with a shift towards the northeast. In the period from 2061 to 2080, the distribution is expected to increase by 8% from its current range, maintaining the northeast shift. The study identified three primary threats: grazing, trampling and harvesting, with livestock activities prevalent in 92% of plots and signs of harvesting in 45%. These findings provide crucial insights into the ecological dynamics, distribution patterns and potential conservation challenges facing the Bhutan poppy in Jigme Dorji National Park's alpine habitats, emphasising the need for informed conservation strategies amidst changing environmental conditions.

Topoğrafya ve Meşcere Yapısının Rüzgâr Devriği Zararlarına Etkisinin Araştırılması: Düzce Orman İşletme Müdürlüğü Örneği

Aim of study: The aim of the study was to determined the tree volume and damage level in windthrow areas and to assess the impact of topographic factors and forest structure on windthrow damaged.
 Area of study: Our study was conducted within the Düzce Forest Management Directorate.
 Material and methods: The windthrow areas within the boundaries of Düzce Forest Management Directorate were obtained from extraordinary yield reports. According to windthrow data verified using Google Earth, the borders for each damage were determined and transferred to ArcMap. The relationships between windthrow areas and enviromental parameters were determined using digital maps and forest management plans. Correlation analysis was applied to find out the relationship between windthrow areas and topographic and forest characteristics. Additionally, variance analysis was performed to determine if there were differences in terms of dominant aspects and forest types between windthrow areas and amounts. T-tests were conducted to determine if there were differences between windthrow areas and amounts and the dominant wind direction. Based on the statistically significant results, an intersect analysis was applied to environmental parameters to generate a windthrow susceptibility map.
 Main results: Windthrow occurred mostly in the southwest aspect, in the Fir-Beech species and in the cd age classes. A statistically significant relationship (p

Residual Stand Structure and Topography Predict Initial Survival and Animal Browsing of Redwood and Douglas-Fir Seedlings Planted in Coastal Forests of Northern California

Successful regeneration of commercial species is central to the long-term sustainability of forests managed for wood production. We studied two species of tree seedlings planted after group selection and single-tree selection harvesting in a 20 ha replicated silviculture experiment in stands dominated by coast redwood (Sequoia sempervirens (D.Don) Endl.). Treatments consisted of complete harvest in 1 ha group selection opening (GS), low-density dispersed retention (LD), aggregated high-density retention (HA), and dispersed high-density retention (HD). One year after planting, seedlings planted on a southwest aspect had the lowest survival rate, while northeast aspects had nearly complete survival rates. As expected, redwood had a higher survival rate than coast Douglas-fir (Pseudotsuga menziesii var menziesii (Mirb.) Franco). Survival rates exhibited a rise-peak-fall pattern with stand density, most notably on southwest-facing slopes, ranking LD > HA ≈ HD > GS treatments. Deer browsing of planted seedlings was a pervasive problem where Douglas-fir were preferentially browsed over redwood. In treatments with higher retention densities, browsing was less likely, ranking GS > LD > HA > HD treatments. Further from watercourses at higher elevation, the probability of browsing diminished. Overall, dispersed treatments outperformed aggregated and GS treatments by simultaneously maximizing survival and minimizing browsing of planted seedlings. We did not perform site preparation or herbicide treatment of re-sprouting hardwoods following harvest, and therefore recommend testing the effectiveness of understory vegetation management to enhance seedling survival. Consideration could also be given to planting more seedlings in anticipation of lower survival rates, and/or implementing seedling protection measures when and where heavy browsing is expected.

Mesic mixed-conifer forests are resilient to both historical high-severity fire and contemporary reburns in the US Northern Rocky Mountains

High-severity fires and short-interval reburns strongly influence forest structure and composition and may overwhelm forest ecosystem resilience and catalyze persistent shifts to non-forest conditions. Recent increases in annual area burned and severity in the western United States (US) highlight the need to better understand the long-term effects of high-severity fire, including interactions with subsequent fires. In the early 20th century, the northern US Rocky Mountains experienced several fire seasons with widespread, high-severity fires, under fire weather comparable with extreme conditions today. The Selway-Bitterroot Wilderness in north-central Idaho has remained an active fire regime with limited suppression and management, making it an ideal location to investigate long-term effects of initial high-severity fires, as well as ecosystem resilience to contemporary reburning. Using field sampling informed by fire history data from 1870 to 2020, we investigated the influence of fire frequency (once, twice, and thrice burned from 1910 to 2017) on forest structure, conifer regeneration, and fuel loading in mesic mixed-conifer forests that burned at high severity in either 1910 or 1934. Tree regeneration was abundant across all three burn histories, and 99% of sample sites were <200 m from the nearest conifer seed source when sampled in 2021. Abundance of snags and coarse woody material was less affected by fire frequency and more impacted by time since last fire. High shrub biomass occurred only on steep southwest aspects with low overstory basal area and was not related to burn history. Live tree composition and density differed across forests with contrasting recent fire histories, but even thrice-burned sites supported abundant conifer tree regeneration, indicating that northern Rocky Mountain mesic mixed-conifer forests that experienced fire during the twentieth century currently remain resilient to wildfire. Wildfire as an ecological process in the Selway-Bitterroot Wilderness likely contributed to ecosystem resilience.

Geographically and Ontologically Oriented Scoping of a Dry Valley and Its Spatial Characteristics Analysis: The Case of the Three Parallel Rivers Region

A dry valley is a special landscape type that is formed by the combined effect of climate and topography. Accurately defining the scope of a dry valley and knowledge of its spatial distribution characteristics can provide data support for relevant studies in the region. Starting from natural ontological characteristics and formation mechanisms, we constructed a geographical ontological model of dry valleys through an analysis of concepts related to the dry valley and combined GIS technology and methods to accurately define the scope and analyze the spatial characteristics of the dry valleys in the Three Parallel Rivers Region (DVT). Our results show that: (1) The geographically and ontologically oriented method developed to define the scope of the dry valley has a high accuracy, with an overall accuracy of 92.3% and a kappa coefficient of 0.84, therefore it can provide a better mechanism for defining the scope of a dry valley on a large scale. (2) The total area and total length of the DVT are 6147.1 km2 and 2125.3 km, respectively. The dry valleys in this region are mainly located in the Tibet Autonomous Region and in the Sichuan and Yunnan provinces in China. (3) The terrain in the DVT is precipitous, and areas with slopes greater than 25° account for 70% of the total area of the dry valleys. The DVT area of sunny aspects (north, northeast, and northwest aspects) is larger than that of shady aspects (south, southeast, and southwest aspects), and the land cover is mainly grassland with a desert substrate. The result of our study can provide data support for further in-depth research in related fields of dry valleys.

Dynamics of physico -chemical properties of soil in response to hilly aspects in community forest, Rampur Palpa

This research was objectively conducted to assess physico-chemical properties of soil among aspects. Total 64 soil samples were collected from 0 to 10 and 10-20 cm depths from North East, South East, North West and South West aspects. The physical and chemical properties of soil were analyzed in the lab. Average moisture content was found highest at North East aspect (39.46±1.11%) at 0-10 cm depth and 37.52±0.96 % at the depth of 10-20 cm. Nitrogen content was the highest 0.378±0.03% at 0-10 cm depth and 0.362±0.04 % at 10-20 cm depth in North East aspect. The amount of Potassium in the forest was found highest at North East aspect with the mean ±SE value of 523.76±75 kg/ha at 0-10 cm depth and 418.92±28.09 kg/ha at 10-20 cm depth. Phosphorus content was found to be highest again at North East aspect which has the mean±SE value of 28.202±2.22 kg/ha at 0-10 cm depth and 25.89±2.51 kg/ha at 10-20 cm depth, Similarly, organic carbon content was found highest again at North East aspect with mean±SE value of 2.18±0.06 % at 0-10 cm depth and 2.031±0.05 % at 10-20 cm depth. Elucidating pH content, the highest value was found at North West aspect with mean value of 6.32±0.19 at 0-10 cm depth and 6.02±0.21 at 10-20 cm depth respectively. Value of C:N at North Eastern aspect was recorded 5.80 at 0-10 cm depth and 5.55 at 10-20 cm depth. The study will be useful for researcher for the further work in soil science.

Impact of Shifting Cultivation on Green Infrastructure: A Remote Sensing Perspective

The study deals with the spatio-temporal dynamics with special reference to shifting cultivation in Nagaland, Northeast India using multi-temporal satellite observation during the last three decades (1987-2017). The study exhibited a significant change in green infrastructure over the temporal scales and highlights the influence of shifting cultivation in the region as evident in the initial decade of observation (1987, 1991, 1996) compared to recent decades barring 2013. The principal component analysis of major vegetation indices highlights a decrease in very high green infrastructure while an increase in very low, moderate, and moderately high green infrastructure (by 69.25%) during 2005-2020 in Nagaland. Although green infrastructure is the most dominant land surface feature (74.25%) in Tuensang district, the large parts were significantly affected due to shifting cultivation (9-17%) and footprint of shifting cultivation as fallow land (29.79% to 30.15%) during 1987-2017. The topographical control was observed on hills with gentle slopes (&gt;15%) with southeastern, south, and southwest aspects for shifting cultivation while an increase was observed in the higher relief. The reduction in the cycle of shifting cultivation and its transformation to permanent intensive agriculture will have a far more negative repercussion on the ecosystem. The study necessitates the incorporation of sustainably managed methods in conjugation with the traditional customs and practices to maintain environmental boundary conditions by means of promotion of agroforestry and tree-based land uses to reshape the adversities of shifting cultivation.

TWINSPAN classification of vegetation from South West aspect of Lower Tanawal, Abbottabad Pakistan

The aim of this research study was to explore the vegetation of Lower Tanawal, Pakistan from South west aspect. The ordination techniques Two-Way Indicator Species Analysis (TWINSPAN), Extended Correspondence Analysis and Canonical Correspondence Analysis were used to classify the data. TWINSPAN classified the 165 species and 24 stands into four plant communities namely Grewia-Dodonaea-Carissa, Melia–Duchesnea–Oxalis, Pinus–Rubus–Cynodon, and Olea–Punica–Rumex community. This study provided information on the Southwest aspect of the Lower Tanawal vegetation, Pakistan.

Tropical montane forest in South Asia: Composition, structure, and dieback in relation to soils and topography

AbstractWe evaluated the composition, structure, and dieback of a montane forest in relation to soils and physiography of an important biogeographic region that has been sparsely studied. Our objectives were to (1) describe the forest composition and structure; (2) assess the current extent of dieback; and (3) relate tree composition, structure, and dieback proneness to edaphic and physiographic measures. We enumerated all live and dead standing plants ≥3 cm dbh, in thirty 20 × 15 m2 overstory plots. We measured all regeneration ≤1 m height in subplots, sampled soils and measures of physiography, and visually rated the proportion of crown dieback, and recorded standing dead trees. Woody plants belonged to 58 species and 25 families, of which 5% were dead. The plant families Lauraceae, Myrtaceae, and Symplocaceae represented over 50% of the basal area; Rubiaceae alone represented 25% of the stems. Multiple regressions revealed measures of edaphic and physiographic factors are associated with tree species richness and diversity, structure (e.g., basal area and stem density), and tree dieback and standing dead trees. Canopy openness and measures of soil toxicity from metals (Al and Cu) on clay‐based soils showed a predictably negative relationship with tree species richness and diversity. Basal area and stem density are positively associated with aspect and slope, and predictably negatively associated with canopy openness. Lastly, dieback and standing dead trees of the dominant canopy tree species are both positively associated with south and southwest aspects. The forest is now in a period of regeneration recovery with high numbers of regenerating secondary successional species. We propose the primary underlying factors that caused the dieback of this forest was a drought during 1970–1980 compounded by accumulations of salts and metals in the soil conveyed by winds from the sea (sodium) and from an ancient period of metallurgy downwind of the forest. However, our results are only suggestive of these causative factors and further study is necessary to confirm or refute these speculative causes for dieback.

Orchid Distribution along the Elevation Gradient in Panchase Forest Conservation Area of Gandaki Province, Nepal

The vegetation composition and elevation play a key role in the distribution of plants. Among the flowering plants, orchids are widely distributed beautiful flowers having ornamental and medicinal values. The Panchase Forest Conservation Area is one of the hot spots for the orchids, a threatened group of the flowering plants. The preceding studies on orchids seem usually focused on documentation of the orchid species and their medicinal values showing no works on orchid species distribution along the elevation gradient and aspects. Therefore, this research was concentrated on assessing orchid distribution along the elevation in the forest of the Middle-mountain. The study was conducted in former Chapakot and Bhadaure-Tamagi Village Development Committees that lie in Pokhara Metropolitan City-23 and Annapurna Rural Municipality-4, Kaski District. Chapakot represents south-west (SW) aspect and Bhadaure-Tamagi represents north-west (NW) aspect. For this study, the belt-transect method with 20 m x 20 m quadrat size at an interval of 100 m elevation was used for assessing the orchid richness along elevation and aspects. Altogether, 61 orchid species, with Eria, Dendrobium, Cymbidium and Bulbophyllum as the most common genera, were found. Among the orchid species, Dendrobium gibsonii was not reported in earlier studies from Panchase area. The orchid richness varied along the elevation and aspect. The SW aspect showed fluctuation in orchid richness, whereas the NW aspect showed humped shaped pattern. Further detailed studies on factors causing distribution of orchids and their relationship with host species need to be conducted for the conservation of orchids in the Panchase Forest Conservation Area.

Evaluating topographic variation as a guide to Cassia crossbill refugia

The Cassia crossbill (Loxia sinesciuris) feeds exclusively on seeds held in serotinous cones of lodgepole pine (Pinus contorta latifolia). Its population, confined to 67 km2 of pine in southern Idaho, declined by ~ 80% between 2003 and 2011 apparently because an increase in the occurrence of hot summer days (≥32 °C) caused the serotinous cones to open and shed their seeds. We hypothesized that the propensity for serotinous cones to open varies across the landscape depending on the maximum temperatures cones experienced. We tested a suite of abiotic variables for predicting the occurrence of open serotinous cones among 1547 trees at 170 sites. The best-supported model indicated that trees with open cones were less frequent on northeastern aspects and as slope increased. Fewer open cones were expected on northeast aspects because they receive less direct solar radiation. However, the decrease in trees with open cones as slope increased on southwest aspects was unexpected. Increased convection on slopes could reduce maximum cone temperatures and account for the decrease of open cones on steeper slopes, regardless of aspects. Although cones are less likely to open on steeper slopes, slopes with southerly aspects are likely the least favorable for pine recruitment and survival. The most favorable sites for both lodgepole pine and the persistence of closed cones are slopes on northeast aspects. Such locations are often dominated by subalpine fir (Abies bifolia). Reforestation of fir-dominated areas with lodgepole pine, therefore, provides a means to expand microclimatic refugia for Cassia crossbills.

Elevational gradients strongly mediate habitat selection patterns in a nocturnal predator

AbstractMountain ecosystems contain strong elevational gradients in climate and vegetation that shape species distributions and the structure of animal communities. Nevertheless, studies of habitat selection for individual species rarely account for such gradients that often result in species being managed uniformly across their range, which may not improve conservation as intended. Therefore, we characterized variation in nocturnal habitat selection by 18 GPS‐tagged California spotted owls (Strix occidentalis occidentalis) along a 1400‐m elevational gradient in the Sierra Nevada, California. We characterized three‐dimensional forest structure with light detection and ranging data that we used in mixed‐effects resource‐ and step‐selection analyses of owl habitat selection. At lower elevations, owls selected stands with shorter trees, sites closer to hard edges between tall forests and open areas, sites with less diversity in forest seral types and sites with more ridge and southwest aspects. In contrast, owls at higher elevations selected the opposite. Within public forests that had taller trees and within their home range core (45% kernel density estimate of GPS points) areas, owls selected forests with less and more canopy cover at low and high elevations, respectively. Outside of their core areas, owls selected areas with fewer and more tall trees at low and high elevations, respectively. These findings may be explained by elevational gradients in prey distribution and variation in owl diet because owls consume more woodrats (Neotoma spp; earlier seral species) at lower elevations and more flying squirrels (Glaucomys sabrinus; older forest species) at higher elevations. Thus, at low elevations and in areas unlikely to support nesting, spotted owls could benefit from management that promotes woodrat habitat by encouraging oak regeneration and creating small brushy openings within forests with shorter (younger) trees. Conversely, at higher elevations, (1) enhancing flying squirrel habitat by promoting large trees and denser canopy on mesic sites and (2) managing for greater cover type diversity on southwest‐facing slopes and ridgetops is more likely to improve foraging habitat quality for spotted owls. The patterns of owl selection over elevational gradients has not been explicitly considered in most habitat management plans but clearly would improve management throughout mountain ecosystems.

Stability and micro‐topographic effects of Sophora moorcroftiana population on a restored alluvial fan, Southern Tibetan Plateau

AbstractThe Tibetan Plateau, a vulnerable eco‐region undergoing global change, is hard to revegetate where land has become desertified due to the harsh habitat conditions. Sophora moorcroftiana shrubs, which are widely distributed in the middle reaches of the Yarlung Zangbo River basin of Tibet, China, have been naturally restored on desertified land during the last few decades. However, the influences of micro‐topography on the distribution and structure of the S. moorcroftiana population have been rarely reported. Here, we first describe the spatial variation of S. moorcroftiana population on a restored alluvial fan, and then explore the effects of micro‐topography on the restored S. moorcroftiana population, through a series of field surveys combined with the data collected by terrestrial laser scanning. The results indicate that the dominant age structure was adult shrubs (30–60 cm). Although the topographic effect had no significant impacts on soil organic matter and some other structural traits, which remained stable on the restored alluvial fan, it changed population density, plant growth, and distribution. The habitat conditions on the southwest aspect wapproximately 20°–25° slope with altitudes ranging between 3,593–3,643 m, conditions that mostly favouring the distribution of the shrub population. The micro‐topography played an important role in species distribution and growth of the S. moorcroftiana population. Our findings could help to understand the effect of micro‐topography on plant population structure and distribution for ecological restoration of desertified land in the Southern Tibetan Plateau.

A Study on Distribution, Habitat Use and Conservation Status of Himalayan Musk Deer (&lt;i&gt;Moschus chrysogaster) &lt;/i&gt;in Askot Wildlife Sanctuary, India

The population of Himalayan musk deer (Moschus leucogaster) synonym Moschus chrysogaster has declined in recent decades and reached an endangered status in its distribution range. The distribution of Himalayan musk deer is very restrictive to Himalayas of Northern India, Nepal, Bhutan and China hence has low population. Musk deer family is being hunted for their musk pod due to high demand in international markets specially in China and North East Asia for their cosmetic and pharmaceutical use. Due to its habitat loss and large scale poaching the species has become endangered. The species is nocturnal, crepuscular and elusive which makes it difficult to study its distribution and habitat use pattern. The present study was carried out in Dharchula range (about 100 sq. km) in Askot wildlife sanctuary (WLS), Uttarakhand, India from August 2017 to May 2019. We used trail sampling and silent drive count method to estimate the distribution, abundance, and habitat use pattern. A total 63 trail transects and 8 Silent Count Drive (SDC) walks were laid in fir mixed, temperate mixed, birch mixed and pure birch forest at different aspect, slope and elevation. We recorded 10 individuals and 39 pellet groups on 63 trail and 8 SDC walks totaling 169 km effort registering an overall encounter rate of 1.18±0.20 individuals/km. We used mixed-effect models to characterize relationships between deer presence-absence data and habitat variables. The study confirmed that musk deer uses fixed defecation sites at higher elevations (3,000-4,300 m) throughout seasons and years. This species was found to use slope ranging between 20° and 55° and were found most abundant between 30° and 45° slope. The largest fraction of musk deer presence was observed in South west aspect and lowest in Northern aspect. The birch mixed forest recorded highest proportion of total musk deer followed by fir mixed forest. The distribution of musk deer was concentrated between 3,500 to 4,000 m a.s.l. A significant difference in density estimates of Himalayan musk deer was observed across the seasons. The encounter rate was higher 1.39±0.13 during autumn and low 0.66±0.22 during winter. It was observed that the species have suffered heavy decline in population in Askot WLS due to large scale collection of a medicinal fungus (Ophiocordyceps sinensis) locally called Keeda Jadi. Recently Ophiocordyceps sinensis also declared as vulnerable species by IUCN due to over exploitation of this fungus in this region. There is an urgent need for conservation plan for musk deer by strengthening the existing local institutional mechanism such as Van Panchayat and Gram Panchayat and integrating the interest of local community in sharing of benefits of the resources generated from the forest.

Análisis del incremento en área basal de Pinus hartwegii Lindl. a diferente altitud y exposición en el cerro de Jocotitlán, Estado de México

Introduction: Basal area increment (BAI) is an indicator of forest productivity that varies with tree age and site factors such as soil and climate. Objective: To generate tree-ring width index (RWI) and BAI chronologies of Pinus hartwegii Lindl., relate them to climatic variables, and study the variation in BAI at different altitudes and aspects. Materials and methods: Four observation sites were identified, combining northwest (NW) and southwest (SW) aspects, as well as altitudes of 3 800 and 3 700 m. At each site, the temperature was recorded every four hours for 435 days and 32 growth ring segments were collected using a Pressler´s increment borer. Tree-ring width was measured and BAI was calculated; the correlation index between these indicators and the climatic variables was Pearson’s correlation coefficient. Results and discussion: The RWI series from the four observation sites had an intercorrelation of 0.33 (P &lt; 0.01). Two low-growth periods were detected, one between 1950 and 1960 and the other between 1990 and 2005. Site SO-3700 had a different growth pattern, due to a second growth phase beginning in 1978, possibly a benefit resulting from increased temperature. The previous autumn temperature, spring temperature and April-September precipitation of the current year explained the variation in BAI (P &lt; 0.05). Conclusion: The BAI of P. hartwegii could respond favorably to the predicted increases in temperature at an altitude of 3 700 m with southwest aspect.

Mitigating Heat Wave and Exposure Damage to "Cabernet Sauvignon" Wine Grape With Partial Shading Under Two Irrigation Amounts.

Rising temperatures in most agricultural regions of the world are associated with a higher incidence of extreme weather events such as heat waves. We performed an experiment to mitigate the impact of heat waves and exposure of berries in grapevine (Vitis vinifera cv. “Cabernet Sauvignon”) with untreated vines (Exposed) or with fruit-zone partial shading (Shaded) under 40 and 80% replacement of crop evapotranspiration (ETc) with sustained deficit irrigation in a factorially arranged experiment. The trial was performed in a vineyard with vertically shoot positioned trellis with a row orientation that concentrated solar radiation exposure on the southwest aspect of the fruit zone. Leaf stomatal conductance (gs) and net carbon assimilation (AN) were significantly lower in shaded leaves under partial fruit-zone shading that resulted in lower pruning mass for Shaded treatments. Stem water potential (Ψstem) responded to a large extent to increased irrigation. However, grapevines with partial fruit-zone shading had transiently better water status under 40% ETc. Cluster maximum temperatures were 3.9°C greater in Exposed grapevines. Exposed clusters had transiently lower acidity and higher pH. However, Exposed clusters on 40% ETc had higher total soluble solids (TSS). The experimental vineyard suffered a 4-day heat wave 21 days before harvest, resulting in 25% of the clusters being damaged in Exposed treatment, regardless of irrigation amount. Furthermore, berries in Exposed treatments suffered a great loss of anthocyanins and flavonols even if they were not damaged by direct solar exposure. The pre-planting decision of using a vertically shoot positioned trellis that concentrated solar radiation on the Southwest aspect offered mild protection in a hot climate region with a sunny growing season with extreme heat events during the execution of study. The extreme conditions under which this study was conducted are not unusual, and have become more expected. Our work provided evidence of the vulnerability of grape berry to heat waves and exposure during heat wave events and possible protection methods to mitigate these effects in situ in context of climate change.

Assessment of vegetation aptitude to accomodate organic beekeeping

The aptitude offered by land vegetation to accommodate organic beekeeping was assessed in the Santuario Apicola Paz de Aculeo, located in the Metropolitan Region of Chile. A multicriteria analysis methodology combining geomatics and remote sensing was designed. For this purpose, critical vegetation variables for forage selection by the bee populations were valued on the main vegetation units cadastrated for the study area. Thereafter, they were subject to a lineal combination that hypothesized several weighting scenarios. The afore-mentioned enabled to classify the units according to their aptitude to accommodate the beekeeping, which were further characterized according to their vegetation vigor throughout the phenological cycle; derived from NDVI (normalized difference vegetation index) composites, as well as to their topographic variability; derived from a DEM (digital elevation model). The results show that no matter the scenario supposed, the vegetation units of the study area can be divided into five aptitude classes, with those embracing the highest aptitude (1 and 2) as the most prevailing; being distributed at variable altitudes of generally southwest aspect. Although the NVDI composites yielded differences between classes, those were small and non-significant, as a variance analysis pointed out. This study seeks to approximate the management and planning of the beekeeping productive system of local scale to the geotechnologies usage. Further efforts could apply a similar methodology on more complex and heterogeneous vegetation areas with the aim of proving its versatility.

Multi-Source Remote-Sensing Monitoring of the Monsoonal Maritime Glaciers at Mt. Dagu, East Qinghai-Tibetan Plateau, China

This research presents a precise evaluation of the recession of monsoonal maritime glaciers at Mt. Dagu, based on multi-source remote-sensing data of an aerial topographic map from 1966 and Landsat MSS, TM, ETM+, and OLI data from 1975 to 2017 for six sub-regions of the glacier covering 1.747±0.068 km 2 at present. The results show that: first, the area of glacier exhibits an exponentially decreasing trend and retreated as much as 5.094 ± 0.301 km 2 during 1975-2017, with a shrinkage rate of 0.120 ± 0.004 km 2 a -1 . Second, the highest area shrinkage rates of glaciers are in the north, northwest, southwest, and south aspects. The largest retreat altitude of the glacier terminus is in the southwest aspect of region 2. Of which, the absolute retreat elevation is 303 m (from 4587 to 4890 m a.s.l.), at a mean rate of 7.2 m a -1 . Third, the temperature has increased at a rate of 0.02754°C a -1 (R 2 = 0.6132, p <; 0.05) by a total of 0.9°C (1961-2017), more higher than the region's average increase. However, there is no significant increasing precipitation trend. The warm-dry trend is aggravated and this is the main reason for the glacier recession. Finally, the accelerated retreat presents a severe challenge to the sustainability of the glaciers and glacier-oriented tourism. Active intervention to maintain the glacier should be urgently considered.

The Importance of Disturbance versus Physiography in Defining Vegetation Composition and Predicting Possible Successional Trajectories

ABSTRACT Regional (climate/soils) and local (aspect) physiography determine plant community composition. However, changes in initial floristic composition after a disturbance may be severe enough to alter the successional trajectory predicted by physiography. We addressed the question of which is more important, disturbance or physiography, in determining vegetation composition and the consequent successional trajectory. We evaluated understory vegetation of forest communities exposed to four disturbance types (control, single burn, diameter-limit cut, and first-removal shelterwood) 2–5 yr postdisturbance. Study sites were located within each disturbance type on northeast and southwest aspects within the Appalachian Plateau and the Ridge and Valley provinces. Vegetation composition was analyzed with nonmetric-multidimensional scaling, two-way nonparametric multivariate ANOVA, and indicator species analysis. The relationship between disturbance and key environmental variables, including canopy opening and ...

BROWN BEAR (URSUS ARCTOS) (CARNIVORA, MAMMALIA) DENS OF THE KRONOTSKY NATURE RESERVE

Seventeen brown bear dens were studied in the Kronotsky Nature Reserve (Russian Far East). The majority of dens were excavated in the ground. The dens were located mainly in the upper part of slopes with southwest aspects in birch forests, dwarf Siberian pine and alder patches. The structure of the dens was typical for brown bear ground dens. There are places in the basin of Shumnaya River in Kamchatka where brown bears prefer to set up their dens.