West Aspects Research Articles

Effect of elevation and aspect on carbon stock of bamboo stands (Bambusa nutans subsp. Cupulata) outside the forest area in Eastern Nepal

Bamboo has emerged as a promising option for climate change mitigation due to its rapid growth, versatility, and renewability. However, in Nepal, there exists a substantial knowledge gap on carbon (C) stock and the influence of aspect and elevation on C stock of bamboo species, particularly in areas outside forests where bamboo is dominant. Therefore, this research was conducted to quantify C stock and aspect-elevation influence on the C stock of Bambusa nutans subsp. cupulata outside the forest area. For this study, three elevation zones (0–400 m, 400–800 m, 800–1200 m) and two aspects (East and West) were considered. A total of 30 square plots having a 100 m2 area were established utilizing purposive sampling due to the scattered distribution of bamboo. Non-destructive methods were applied to measure bamboo culm diameters, while composite soil samples were systematically collected from 30 cm depth using soil augers and core samplers. Clump density (400 ha⁻¹), culm density (42,480 ha⁻¹) and culm diameter (6.82 ± 0.41 cm) were highest at middle elevations (p < 0.05), with no significant difference due to aspect (p > 0.05). The total mean C stock potential of B. nutans was 148.73 ± 3.43 Mg ha⁻¹. Our results indicated a significant difference in C stock among elevation zones, with middle elevation zones (161.77 ± 6.74 Mg ha-1) exhibiting notably higher C stock compared to both lower (150.26 ± 2.69 Mg ha-1) and higher (134.17 ± 4.26 Mg ha-1) elevation zones. Furthermore, East aspect was found to have significantly (p < 0.05) higher soil organic C stock (18.52 ± 1.32 Mg ha-1) compared to West aspect (11.4 ± 1.01 Mg ha-1). Further research is needed to explore other complex environmental interactions with C stock potential for better climate change strategies. Incorporating bamboo C into Nepal's REDD+ initiative can be crucial for optimizing opportunities to earn C credits.

Thirty years of forest productivity in a mountainous landscape: The Yin and Yang of topography

AbstractWe measured light‐related patterns of primary productivity within a topographically complex Oregon watershed over a 30‐year period. Second‐growth conifer densities were experimentally altered in 1981. Plots receiving at least 3434 MJ m−2 over a 6‐month growing season averaged 40% greater aboveground net primary productivity (ANPP) than those receiving less light (p = 0.000). Unthinned stands potentially built enough LAI to compensate for low light, but risked mortality that exceeded resilience. The two light levels acted as basins of attraction for other physiological and ecological processes, including size–density relationships and limiting foliar nutrients. Initial (1981) LAI and the irradiation step (above or below 3434 MJ m−2) explained 60% of variation in a 30‐year ANPP. Irradiation within each light group did not affect ANPP. At high irradiation, foliar N/Ca and slope steepness (both negative) explained 58% of the variation in residuals from the initial models, while at low irradiation on north, east, and west aspects, 83% of residual variation was explained by foliar Mg (+), understory cover (+), and 30‐year mortality (−). Light use efficiency (LUE) of fully stocked stands correlated with LAI and foliar N/K. Results suggest that understory influence on tree foliar N (+ or −) enhances ANPP by regulating critical nutrient ratios. Mortality reduced or eliminated differences among thinning levels, which did not vary at low light and only between unthinned and heavily thinned at high light. Values associated with relatively open forests (biodiversity, resilience) may be attained without large sacrifice of long‐term carbon sinks. In our study, light interacts with topography to produce nonlinear dynamics in which small changes in irradiation can have large consequences. Reduced sunlight has been suggested as a geoengineering option to combat global warming. Ecological changes out of proportion to lowered irradiation are a distinct possibility, including sharp reductions in terrestrial carbon sinks.

Soil fungal communities varied across aspects of restored grassland in former mining areas of the Qinghai-Tibet Plateau.

To determine whether different aspects lead to a heterogeneous distribution of soil fungi, we investigated artificially established alpine grasslands in the Muli mining area in the Qinghai-Tibet Plateau. Employing high-throughput sequencing techniques, we analyzed the composition, diversity, and function of soil fungal communities across various aspects (flat, East-facing, South-facing, West-facing, North-facing). We also examined their relationships with environmental factors. Soil fungal communities of restored alpine grasslands differed significantly across aspects in terms of the dominant phyla, classes and species level. Compared with No aspect, the Shannon index of fungi respectively decreased by 2.99%, 19.32%, 19.37% and 10.56% for East aspect, South aspect, West aspect and North aspect, respectively, and the Chao1 index of fungi respectively decreased by-2.44%, 35.50%, 42.15% and 3.21%, respectively. A total of 22 different types of fungi were identified in the study area. Predictive analysis, based on PICRUSt2, indicated that the primary functions of the fungal communities across different aspects were aerobic respiration I (cytochrome c) and aerobic respiration II (cytochrome c). Among the environmental variables, total phosphorus (P) and total nitrogen (N) were the principal factors influencing the fungal community composition.In conclusion, aspect plays a significant role in shaping the composition of fungal communities and also affects their overall diversity.

Two invasive Hieracium species’ potential distributions within the Greater Yellowstone Ecosystem were defined using invasion susceptibility models and habitat typing

Invasive Hieracium plant species are invading the Greater Yellowstone Ecosystem. The potential distribution of orange hawkweed (Hieracium aurantiacum) and meadow hawkweed (Hieracium caespitosum) were estimated using habitat susceptibility models to assist land managers’ management of these invasive plants. The objectives of this study were to: (1) develop models describing susceptibility of ecosystems to hawkweed invasion, (2) identify indicator species of orange hawkweed and meadow hawkweed, (3) determine habitat types where these invasive hawkweeds might occur, and (4) create habitat susceptibility maps for management planning and ground surveys. Models were developed using a Mahalanobis distance similarity technique from remotely sensed biotic and abiotic variables, as well as known location data for orange and meadow hawkweed. Ground validation was conducted to assess model weaknesses and subsequent model modification. Indicator plant species were identified as surrogates to determine the likelihood of hawkweed presence during ground survey. Transect data collected from areas susceptible to invasion also were used to determine habitat types where hawkweed might occur. The best model included eight variables: north–south aspect, east–west aspect, slope, NDVI, NDWI, blue spectral band, green spectral band, and precipitation. High susceptibility (65 + % likelihood of suitable habitat) consisted of 66,000 ha for meadow hawkweed and 35,000 ha for orange hawkweed, 5.0% and 2.7% of the study area, respectively. Meadow hawkweed and orange hawkweed had seven and three indicator plant species, respectively. Predicted hawkweed habitat susceptibility encompassed nine habitat types, ranging from xeric sagebrush steppe to wet forests and they overlapped except at the xeric habitat type. Habitat susceptibility models save costs and allow survey prioritization to those areas most susceptible to invasion.

Population biology, ecological niche modelling of endangered and endemic Pittosporum eriocarpum Royle in Western Himalaya, India

Pittosporum eriocarpum, an endemic, endangered, and multipurpose tree of the Indian Himalayan Region, is found in restricted pockets. The available studies on the species reveals that the studies are mostly focused on taxonomy and ethnobotany/resource use patterns. Therefore, the present study assessed the populations; analyzed the physico-chemical properties of soil; developed Ecological Niche Model; and standardized seed germination protocol for conservation. Sixteen populations of P. eriocarpum were surveyed and sampled in Himachal Pradesh. The density of P. eriocarpum ranged from 10 to 40 Ind/ha, it was highest in the rocky habitat (15 Ind/ha) and west aspect (40 Ind/ha). Pinus roxburghii, Pistacia chinensis ssp. integerrima, Grewia optiva, Albizia lebbeck, Quercusoblongata and Bauhinia variegata were major associated trees. Soil was analysed for the physico-chemical properties. In most of the populations,P. eriocarpum was in the form of saplings and seedlings. P. eriocarpum density had a significant negative correlation with pH. To predict potentially suitable habitats for P. eriocarpum, species occurrence data, bio-climatic variables, and the maximum entropy distribution modelling approach were used. The model's results revealed that 9.37 % of Himachal Pradesh is appropriate for species reintroduction. Both GA3 and KNO3 were highly effective for increasing germination and decreasing MGT and played a significant role in the seed germination. Despite the high viability of seeds, species cannot regenerate and spread in their native environments. This might be a result of overexploitation, intensive grazing, and competition among associated species. For in-situ conservation, regular monitoring and complete habitat protection are recommended.

Effects of aspect on phenology of Larix gmelinii forest in Northeast China

The response of vegetation phenology to global climate change is one of the main forms in terrestrial ecosystem change, the study of vegetation phenology is an important complement to the understanding of how global climate change affects ecosystems in multiple dimensions. We selected the distribution area of Larix gmelinii in The Greater Khingan Mountains as a case area by eliminating the heterogeneity of vegetation types, with the support of Google Earth Engine platform, we studied the effects of different aspects and land surface temperature (LST) on remote sensing phenology (RSP) that is defined as start of growing season (SOS), end of growing season (EOS) and length of growing season (LOS) respectively in the study area through Normalized Difference Vegetation Index (NDVI) changes. The results showed that SOS advanced in different aspects during the study period, and the advance amplitude of SOS on the east and west aspect was greater than that on the south and north. Except for the east aspect, EOS showed a slight postponed, and LOS was prolonged on all aspects. The latitude difference between 51° and 53° N had no significant effect on L. gmelinii in different aspects. LST had an obviously direct effect on the RSP of L. gmelinii in different aspects, and the effect of LST on SOS and LOS was significantly greater than that on EOS. The effect of LST on SOS and LOS was significant in April and spring. The main contributor to the increase of LOS was the advance of SOS, while the postponed of EOS has a relatively small contribution to LOS. Due to the redistribution of meteorological factor by aspect, the spatial and temporal heterogeneity of RSP tends to be complex, so determining the same aspect is one of the main ways to reduce the phenological heterogeneity in the study of vegetation RSP.

Analisis Modal Manusia, Investasi, dan Teknologi terhadap Pertumbuhan Ekonomi Sumatera Barat

This study aims to identify and analyze. (1) What is the impact of labor on theeconomic growth of West Sumatra? (2) What is the impact of human capital onthe economic growth of West Sumatra? (3) What is the impact of investment onthe economic growth of West Sumatra? (4) What is the impact of technology onthe economic growth of West Sumatra, and (5) What is the impact of labor,human capital, investment, and technology on the economic growth of WestSumatra? This study is descriptive and inductive using panel data regressionanalysis using a random-effects model (REM) method using time series 2017-2020 taken from 19 district/city across province from related agencies in WestSumatra.The results show that the effects of labor, human capital, investment, andtechnology at the same time had a significant positive impact on WestSumatra's economic growth. In addition, in part, (1) labor has negative andslightly impact on West Sumatra's economic growth, (2) human capital has apositive and significant impact on West Sumatra's economic growth, and (3)investment study on economic growth in West Sumatra that has a positive andslightly impact. West Sumatra. West Sumatra, (4) Technology has a negativeand significant impact on West Sumatra's economic growth. Therefore, labor,human capital, investment, and technology are the most important aspects ofWest Sumatra's economic growth.

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.

Iran’s Look to the East Policy in the Framework of Bounded Rationality Model

Doğu’ya Bakış politikası; İran’ın, Batı ile yüzleşmek için Doğu ülkeleriyle ilişkilerini güçlendirmesini hedefleyen bir dış politika vizyonudur. İlk kez Cumhurbaşkanı Mahmud Ahmedinejad Dönemi’nde İran’ın maruz kaldığı yaptırım ve izolasyonu kırmak amacıyla uygulanmaya başlanmıştır. Ancak Hasan Ruhani’nin 2013 yılında cumhurbaşkanlığı görevine gelmesiyle birlikte izlediği Batı ile yapıcı angajman politikası kapsamında Doğu’ya Bakış politikasının Batı’yı dengeleme yönü ön plana çıkmıştır. ABD Başkanı Donald Trump’ın Mayıs 2018’de Kapsamlı Ortak Eylem Planı’ndan (KOEP, Nükleer Anlaşma) çekilerek İran’a karşı sert yaptırımlar uygulamasına istinaden İran dış politikasının yönü bir kez daha Doğu’ya dönmüştür. İran’da daha çok muhafazakâr cephe tarafından desteklenen Doğu’ya Bakış politikasının, İbrahim Reisi’nin Cumhurbaşkanı olmasıyla birlikte yeniden İran dış politikasında öne çıktığı görülmüştür. Ancak Reisi hükûmetinin uyguladığı şekliyle Doğu’ya Bakış politikası, çeşitli kısıtlama ve çıkmazlarla karşı karşıyadır. Bu makalenin amacı, söz konusu politikayı dış politika analizi modelleri arasında yeri olan sınırlı rasyonellik modeli perspektifinden değerlendirmek ve bu politikanın esasen mutlak bir rasyonel tercih olmadığını, dış politika karar alıcılarının sınırlı alternatifler arasından en uygun olanını seçmesiyle oluşan zorunlu ve kısıtlı bir tercih olduğunu ortaya koymaktır.

Recent Changes in Glaciers in the Northern Tien Shan, Central Asia

The Tien Shan is regarded as the “Water tower of Central Asia,” being a solid reservoir of freshwater resources and also a natural and early warning indicator of climate change. Research on glaciers is important for the sustainable development and management of water resources in Central Asia. This study investigated the spatiotemporal dynamics of glaciers in the northern Tien Shan from 1990 to 2015 using multi-source remote sensing and meteorological data. The results showed that the total area and volume of glaciers in the northern Tien Shan exhibited negative trends, decreasing by 456.43 km2 (16.08%) and 26.14 km3 (16.38%), respectively. The reduction in the total glacier area exhibited an accelerating trend, decreasing by 0.60%/a before 2000, but by 0.71%/a after 2000. Glaciers in the outer northern Tien Shan region, with areas &lt; 2 km2 showed the greatest shrinkage, especially those in the northeastern and southwestern regions. All aspects in the northern Tien Shan exhibited negative trends in the glacier area, especially in the east–west aspects (shrinkage of 24.74–38.37%). Regarding altitude, the termini of glaciers rose continuously from 1990 to 2015, particularly for glaciers below 3700 m, with a total area decrease of 30.37%, and the lower altitude of the glaciers showed a higher area decrease.

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.

Analysis of Near-Surface Temperature Lapse Rates in Mountain Ecosystems of Northern Mexico Using Landsat-8 Satellite Images and ECOSTRESS

Mountain ecosystems provide environmental goods, which can be threatened by climate change. Near-Surface Temperature Lapse Rate (NSTLR) is an essential factor used for thermal and hydrological analysis in mountain ecosystems. The aims of the present study were to estimate NSTLR and to identify its relationship with aspect, Local solar zenith angle (LSZA) and Evaporative Stress Index (ESI) for two seasons of the year in a mountain ecosystem at the North of Mexico. Normalized Land Surface Temperature (NLST) was estimated using environmental and topographical variables. LSZA was calculated from slope to consider the effect of solar position. NSTLR was estimated through simple linear models. Observed NSTLR was 9.4 °C km−1 for the winter and 14.3 °C km−1 for the summer. Our results showed variation in NSTLR by season. In addition, aspect, LSZA and ESI also influenced NSTLR regulation. In addition, Northwest and West aspects exhibited the highest NSTLR. LSZA angles closest to 90° were related with a decrease in NSTLR for both seasons. Finally, ESI values associated with less evaporative stress were related to lower NSTLR. These results suggest potential of Landsat-8 LST and ECOSTRESS ESI to capture interactions of temperature, topography, and water stress in complex ecosystems.

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.

Species dispersal along rivers and streams may have variable importance to metapopulation structure

The ability to prioritize habitats that have spatially varied contributions to species persistence can produce synergistic benefits for regional conservation efforts. However, conservation in spatially diverse landscape-networks requires considering dispersal asymmetry in the context of ecological connectivity and metapopulation persistence. By developing an approach based on metapopulation theory, this study prioritized the importance of habitat (as determined by the habitat quality and spatial position in networks) on metapopulation structure in mountainous streams. As a case study, we examined dispersal via overland and instream networks in a riverine mayfly Rhithrogena sp. cf. japonica in a mountain range of Southwest China. Compared to flow velocity, water depth, and instream nutrient-levels, water temperature was a key factor in determining local habitat suitability for R. sp. cf. japonica. Higher water temperature was linked to poor habitat suitability. Instream pathways were the main dispersal corridors compared with overland movement between tributaries for this mayfly. In basins on the east aspect of this mountain range, either monotonically increasing (i.e., never decreasing) or unimodal (i.e., with a single peak) patterns demonstrated the importance of riverine habitats that occur along elevational gradients. However, the importance of habitat appeared to show no definite patterns with elevation on the west aspect. In terms of metapopulation structure, local quality of habitat contributed more to the regional importance of habitat than its spatial position in the networks. The framework presented highlights that the importance of riverine habitats may be quite variable in species having directional dispersal networks across the fluvial landscape in mountainous areas. Results from this framework can serve as the basis to apply a mechanistic understanding to managing and protecting native populations through regional restoration actions.

Metacommunity Structures of Macroinvertebrates and Diatoms in High Mountain Streams, Yunnan, China

The metacommunity concept has received increasing interest in the past two decades. However, there has been limited research examining metacommunity structure of communities in high mountain streams. These ecosystems are often physically constrained and can display large environmental gradients within a relatively small spatial extent. Here, we examined metacommunity structures of stream organisms in a high mountain region, which is part of the Hengduan Mountains region in the Southwest China. Macroinvertebrates and diatoms were collected from six streams in two opposite aspects of the same mountain with different connectivity between streams. On the west aspect, streams are tributaries of a river (i.e. river-connected) while streams flow into a lake (i.e. lake-connected) on the east aspect. We used Elements of Metacommunity Structure analysis to explore the metacommunity structuring of these two biological models. We also compared the contribution of dispersal and environmental filtering in structuring metacommunities by looking at Euclidean, network, topographic, and environmental distances. Communities of diatoms and macroinvertebrates were structured with clear turnover on both aspects. Further, diatom communities exhibited Clementsian structure on both aspects. Macroinvertebrates exhibited different metacommunity structures on the river-connected aspect (Quasi-Clementsian) and lake-connected aspect (Clementsian). Our results indicated that on the lake-connected aspect, environmental filtering had a stronger association with community dissimilarity than on the river-connected aspect for both macroinvertebrate and diatom communities. Diatom communities were more influenced by environmental filtering on the east aspect with weakened network connectivity compared with those on the west aspect. Our results also emphasized the potential effects of biotic interactions between macroinvertebrates and diatoms on shaping community structures of one other. Given that high mountain streams are scarcely examined, our study provides substantial elements to further understand metacommunity structure and highlights the necessity of future research to reveal the underlying mechanisms of community structuring in these remote ecosystems.

Consequences of Ventenata dubia 30 years postinvasion to bunchgrass communities in the Pacific Northwest

AbstractVentenata [Ventenata dubia (Leers) Coss.], an invasive winter annual grass, negatively impacts grassland community composition and function in the Pacific Northwest. Ventenata dubia established in Palouse prairie (PP) and canyon grasslands (CG) of northern Idaho/eastern Washington in the mid-1980s to early 1990s. Understanding and comparing patterns of invasion can elucidate future trends as its range expands. We performed surveys in PP (2012 and 2013) and CG (2018) to assess V. dubia abundance. Specifically, we correlated species richness, Shannon diversity, rank abundance, and indicator species with no, low (&lt;12.5%), and high (&gt;12.5%) V. dubia cover. We used nonmetric multidimensional scaling analysis (NMDS) to visualize species similarities and associations with abiotic variables. In both ecoregions, V. dubia was very common, appearing in nearly 60% of 450 plots. When present, V. dubia cover averaged 26% (±2.3 SE) in PP and 19% (±1.8 SE) in CG. Indigenous plant species richness and diversity were lowest in plots with high V. dubia cover. In CG, this relationship held for nonindigenous species; in PP, nonindigenous plant richness and diversity were higher with high V. dubia cover. Ventenata dubia and other winter annual grasses (Bromus spp., medusahead [Taeniatherum caput-medusae (L.) Nevski]) were moderately associated according to the NMDS analysis. Indicator species analysis showed V. dubia was positively associated with nonindigenous winter annual grasses and negatively associated with indigenous low shrub species. Abiotic factors that explained V. dubia abundance included shallow soils and a south to west aspect. Overall, these findings indicate V. dubia can successfully invade both dry and relatively wet plant communities and is more abundant than other invasive annual grasses. We suggest these findings foreshadow what will happen in sagebrush steppe and Great Plains grasslands, regions where V. dubia recently became established.

Diurnal Pine Bark Structure Dynamics Affect Properties Relevant to Firebrand Generation

Firebrands are an important agent of wildfire spread and structure fire ignitions at the wildland urban interface. Bark flake morphology has been highlighted as an important yet poorly characterized factor in firebrand generation, transport, deposition, and ignition of unburned material. Using pine species where bark flakes are the documented source of embers, we conducted experiments to investigate how bark structure changes in response to diurnal drying. Over a three-day period in a longleaf pine (Pinus palustris Mill.) stand in Florida, we recorded changes in temperature, moisture content, and structure of bark across different facing aspects of mature pine trees to examine the effects of varying solar exposure on bark moisture. We further compared results to bark drying in a pitch pine (Pinus rigida Mill.) plantation in New Jersey. Under all conditions, bark peeled and lifted away from the tree trunk over the study periods. Tree bole aspect and the time of day interacted to significantly affect bark peeling. General temperature increases and moisture content decreases were significantly different between east and west aspects in pitch pine, and with time of day and aspect in longleaf pine. These results illustrate that bark moisture and flakiness is highly dynamic on short time scales, driven largely by solar exposure. These diurnal changes likely influence the probability of firebrand production during fire events via controls on moisture (ignition) and peeling (lofting).

Early Evidence of Shifts in Alpine Summit Vegetation: A Case Study From Kashmir Himalaya.

Under the contemporary climate change, the Himalaya is reported to be warming at a much higher rate than the global average. However, little is known about the alpine vegetation responses to recent climate change in the rapidly warming Himalaya. Here we studied vegetation dynamics on alpine summits in Kashmir Himalaya in relation to in situ measured microclimate. The summits, representing an elevation gradient from treeline to nival zone (3530–3740 m), were first surveyed in 2014 and then re-surveyed in 2018. The initial survey showed that the species richness, vegetation cover and soil temperature decreased with increasing elevation. Species richness and soil temperature differed significantly among slopes, with east and south slopes showing higher values than north and west slopes. The re-survey showed that species richness increased on the lower three summits but decreased on the highest summit (nival zone) and also revealed a substantial increase in the cover of dominant shrubs, graminoids, and forbs. The nestedness-resultant dissimilarity, rather than species turnover, contributed more to the magnitude of β-diversity among the summits. High temporal species turnover was found on south and east aspects, while high nestedness was recorded along north and west aspects. Thermophilization was more pronounced on the lower two summits and along the northern aspects. Our study provides crucial scientific data on climate change impacts on the alpine vegetation of Kashmir Himalaya. This information will fill global knowledge gaps from the developing world.

Effects of Different Geographical Aspects and Ontogenetic Variability on Total Hypericin Content of Hypericum triquetrifolium Turra. and Hypericum scabrum L.

The present study was conducted to determine the total hypericin contents of Hypericum triquetrifolium Turra. and Hypericum scabrum L. species which are naturally distributed in the flora of Siirt province, Turkey. Hypericin contents of Hypericum species grown in different geographical aspects (North, South, East, and West), and it was measured at different harvest times (full blooming and post blooming period). In the current study, it has been determined that total hypericin content varies considerably according to aspects, plant developmental stages (ontogenetic variance), and species. According to species x aspect interaction, the highest total hypericin content was recorded from the west aspect (3.13 mg/g) in Hypericum triquetrifolium, while, the lowest hypericin content was also obtained from the west aspect (1.22 mg/g) in Hypericum scabrum. When the highest total hypericin content was analyzed according to aspect x species x harvest time interaction, the highest total hypericin content was produced from Hypericum triquetrifolium at the harvest of west aspect with 5.28 mg/g, while the minimum amount of hypericin was obtained from the same aspect in Hypericum scabrum with 0.50 mg/g. In species x harvest time interaction, the highest total hypericin content was obtained from the full bloom (3.10 mg/g) harvest in Hypericum triquetrifolium, while the lowest hypericin was obtained from the full bloom (1.26 mg/g) harvest in Hypericum scabrum. The data suggest that the average total hypericin content was 2.26 mg/g in Hypericum triquetrifolium and 1.28 mg/g in Hypericum scabrum.

MUŞ MERKEZE AİT KIYIBAŞI KÖYÜ MERASININ VERİM VE KALİTESİNİN BELİRLENMESİ

This study was carried out in order to determine the hay yield and quality of the rangelands of Kiyibasi Village rangeland in the central district of Mus. In this study; hay yield, crude protein yield, crude protein content, crude ash content, acid detergent fiber (ADF), neutral detergent fiber (NDF), digestible dry matter (DDM), dry matter intake (DMI) and relative feed value (RFV) properties were investigated. In the study; hay yields ranged between 30.37 kg/da and 55.97 kg/da according to the rangeland aspects and rangeland aspects have been found to be statistically significant 1% in terms of hay yield. The highest crude protein content of hay in the rangeland was found to be in the East (14.37%) and statistically in the same group in the South and West aspects. Crude protein yield ranged between 3.31 kg/da and 7.68 kg/da according to rangeland aspects and it was found to be statistically significant 1% in rangeland aspects. As a result of the research; crude ash, NDF, ADF, DDM, DMI ratios and RFV were determined between 6.4-8.7%, 57.0-59.8%, 21.2-34.0%, 62.4-72.3%, 2.00-2.10% and 102.0-112.5, respectively.