Percent Slope Research Articles

Infection Severity of Arceuthobium oxycedri (Viscaceae) in Two Protected Areas in the Alborz Mountains, Iran: A Case Study

ABSTRACTThis study investigated the severity of mistletoe infection on junipers and the relationship between tree characteristics, physiographic factors and mistletoe infection. The study was conducted in two protected areas: Parvar and Miankouh Tash in Semnan Province, Iran. A dwarf mistletoe‐infested area of 400 ha was sampled by placing a 250 × 250 m grid over a map of each study area. A 20 × 20 m (400 m2) plot was placed at the intersection of grid lines. This resulted in a total of 110 forested plots: 45 plots in Parvar and 65 plots in Miankouh Tash. In each plot, all live junipers were measured for total height, crown area, collar diameter and crown diameter. Mistletoe severity was estimated using the 6‐class dwarf mistletoe rating system (DMR). Dead trees were also recorded and examined for evidence of past mistletoe infection. The Boruta algorithm was used for feature selection, and the selected features were utilised for predicting DMR using a random forest (RF) model. Over 40% of junipers in the sample plots were infected and 7.5% were dead. Mortality was greater in severely infested plots compared to uninfested and lightly infested plots. The results of univariate analysis demonstrated that the largest trees across plots were more severely infected. Infection severity was highest on steep terrains (slopes more than 60%) where the largest junipers were growing. Based on Boruta feature selection algorithm, collar diameter, tree height and crown area of junipers have been detected as the most important variables for the explanation of infection severity. Crown diameter, geographical aspect, density of juniper trees, altitude and juniper canopy cover were classified as tentative variables in this model. Slope percentage beside two variables related to stand characteristics including all woody species (basal area and tree density) were the rejected variables. The correlation coefficient (r) and root mean square error (RMSE) between the predictions by RF and the measured DMR were 0.83 and 0.53 respectively. These results indicate that the selected environmental variables can be used for spatial prediction of DMR in both study areas. Because increased mortality was observed for severely infected areas, more efficient management methods are needed to control the dwarf mistletoe populations in the Alborz Mountains.

Gadoxetic acid-enhanced magnetic resonance imaging in the assessment of hepatic sinusoidal obstruction syndrome in a mouse model.

Neoadjuvant chemotherapy can cause hepatic sinusoidal obstruction syndrome (SOS) in patients with colorectal cancer liver metastases and increases postoperative morbidity and mortality. To evaluate T1 mapping based on gadoxetic acid-enhanced magnetic resonance imaging (MRI) for diagnosis of hepatic SOS induced by monocrotaline. Twenty-four mice were divided into control (n = 10) and experimental (n = 14) groups. The experimental groups were injected with monocrotaline 2 or 6 days before MRI. MRI parameters were: T1 relaxation time before enhancement; T1 relaxation time 20 minutes after enhancement (T1post); a reduction in T1 relaxation time (△T1%); and first enhancement slope percentage of the liver parenchyma (ESP). Albumin and bilirubin score was determined. Histological results served as a reference. Liver parenchyma samples from the control and experimental groups were analyzed by western blotting, and organic anion transporter polypeptide 1 (OATP1) was measured. T1post, △T1%, and ESP of the liver parenchyma were significantly different between two groups (all P < 0.001) and significantly correlated with the total histological score of hepatic SOS (r = -0.70, 0.68 and 0.79; P < 0.001). △T1% and ESP were positively correlated with OATP1 levels (r = 0.82, 0.85; P < 0.001), whereas T1post had a negative correlation with OATP1 levels (r = -0.83; P < 0.001). T1 mapping based on gadoxetic acid-enhanced MRI may be useful for diagnosis of hepatic SOS, and MRI parameters were associated with OATP1 levels.

National age-specific mortality trends for cervical and breast cancers in urban–rural areas of China from 2009 to 2021: a population-based analysis

BackgroundCervical and breast cancers are among the top 4 leading causes of cancer-related mortality in women. This study aimed to examine age-specific temporal trends in mortality for cervical and breast cancers in urban and rural areas of China from 2009 to 2021.MethodsAge-specific mortality data for cervical and breast cancers among Chinese women aged 20–84 years were obtained from China’s National Disease Surveillance Points system spanning the years 2009 to 2021. Negative binomial regression models were utilized to assess urban–rural differences in mortality rate ratios, while Joinpoint models with estimated average annual percent changes (AAPC) and slopes were employed to compare temporal trends and the acceleration of mortality rates within different age groups.ResultsFrom 2009 to 2021, there was a relative increase in age-specific mortality associated with the two cancers observed in rural areas compared with urban areas. A rising trend in the screening age of 35–64 [AAPC: 4.0%, 95% confidence interval (CI) 0.5–7.6%, P = 0.026] for cervical cancer was noted in rural areas, while a stable trend (AAPC: − 0.7%, 95% CI − 5.8 to 4.6%, P = 0.78) was observed in urban areas. As for breast cancer, a stable trend (AAPC: 0.3%, 95% CI − 0.3 to 0.9%, P = 0.28) was observed in rural areas compared to a decreasing trend (AAPC: − 2.7%, 95% CI − 4.6 to − 0.7%, P = 0.007) in urban areas. Urban–rural differences in mortality rates increased over time for cervical cancer but decreased for breast cancer. Mortality trends for both cervical and breast cancers showed an increase with age across 4 segments, with the most significant surge in mortality observed among the 35–54 age group across urban and rural areas, periods, and regions in China.ConclusionsSpecial attention should be given to women aged 35–54 years due to mortality trends and rural–urban disparities. Focusing on vulnerable age groups and addressing rural–urban differences in the delivery of cancer control programs can enhance resource efficiency and promote health equity.

Assessment of Soil Erosion within the Gayathripuzha River Basin Using RUSLE Model and GIS Tools

Soil erosion, a natural phenomenon accelerated by human activities, became a major problem for agricultural land use and for water quality concerns. Soil erosion by water is influenced by various factors like climate, nature of land surface, slope steepness, soil properties, land cover, and management practices. Estimation of soil erosion is essential to know the nature and quantity of soil loss and create specific strategies for soil conservation. This research paper thoroughly examines the susceptibility of soil erosion in the Gayathripuzha river basin in Kerala, India, which is encompassing a wide area of around 961 km². Employing the Revised Universal Soil Loss Equation (RUSLE), this investigation assesses the influential factors affecting soil erosion, which comprise rainfall (R Factor), soil erodibility (K Factor), topography (LS Factor), land usage (C Factor), and the impact of conservation measures (P Factor). The study was conducted using Geographic Information System (GIS) tools like ArcGIS 10.8 Desktop and integrating data on rainfall, soil properties, land topographic features, and land use. Rainfall erosivity is a major factor causing erosion in Gayathripuzha river basin and it ranges from 746.03 to 1222.35 MJ mm ha−1 h−1 y−1 in the river basin. Soil erodibility factor also varies widely within the region. Slope length and steepness factor showed that highland ecosystems are present only in a small area of the river basin. Variation in land use and land cover also influenced the soil erosion within the area. The estimated average annual soil erosion ranges from 0 to 133.18 t ha-1 yr-1 within the research site. The research found that soil erosion varied greatly across the study area. Regions with slopes over 50% had much higher erosion rates, while most of the study area had low erosion levels. Notably, the intensity of soil erosion demonstrated a positive correlation with slope percentage, with areas classified as bare ground demonstrating the highest erosion rates. These findings emphasize the necessity for targeted and comprehensive conservation strategies tailored to the diverse landscape of the region to effectively manage soil erosion and mitigate its adverse impacts.

The influence of climate change on the future distribution of two Thymus species in Iran: MaxEnt model-based prediction

Within a few decades, the species habitat was reshaped at an alarming rate followed by climate change, leading to mass extinction, especially for sensitive species. Species distribution models (SDMs), which estimate both present and future species distribution, have been extensively developed to investigate the impacts of climate change on species distribution and assess habitat suitability. In the West Asia essential oils of T. daenensis and T. kotschyanus include high amounts of thymol and carvacrol and are commonly used as herbal tea, spice, flavoring agents and medicinal plants. Therefore, this study aimed to model these Thymus species in Iran using the MaxEnt model under two representative concentration pathways (RCP 4.5 and RCP 8.5) for the years 2050 and 2070. The findings revealed that the mean temperature of the warmest quarter (bio10) was the most significant variable affecting the distribution of T. daenensis. In the case of T. kotschyanus, slope percentage was the primary influencing factor. The MaxEnt modeling also demonstrated excellent performance, as indicated by all the Area Under the Curve (AUC) values exceeding 0.9. Moreover, based on the projections, the two mentioned species are expected to undergo negative area changes in the coming years. These results can serve as a valuable achievement for developing adaptive management strategies aimed at enhancing protection and sustainable utilization in the context of global climate change.

Efficiency evaluation of low impact development practices on urban flood risk

Urban flood risk assessment delivers invaluable information regarding flood management as well as preventing the associated risks in urban areas. The present study prepares a flood risk map and evaluate the practices of low-impact development (LID) intended to decrease the flood risk in Shiraz Municipal District 4, Fars province, Iran. So, this study investigate flood vulnerability using MCDM models and some indices, including population density, building age, socio-economic conditions, floor area ratio, literacy, the elderly population, and the number of building floors to. Then, the map of thematic layers affecting the urban flood hazard, including annual mean rainfall, land use, elevation, slope percentage, curve number, distance from channel, depth of groundwater, and channel density, was prepared in GIS. After conducting a multicollinearity test, data mining models were used to create the urban flood hazard map, and the urban flood risk map was produced using ArcGIS 10.8. The evaluation of vulnerability models was shown through the use of Boolean logic that TOPSIS and VIKOR models were effective in identifying urban flooding vulnerable areas. Data mining models were also evaluated using ROC and precision-recall curves, indicating the accuracy of the RF model. The importance of input variables was measured using Shapley value, which showed that curve number, land use, and elevation were more important in flood hazard modeling. According to the results, 37.8 percent of the area falls into high and very high categories in terms of flooding risk. The study used a stormwater management model (SWMM) to simulate node flooding and provide management scenarios for rainfall events with a return period ranging from 2 to 50 years and five rainstorm events. The use of LID practices in flood management was found to be effective for rainfall events with a return period of less than 10 years, particularly for two-year events. However, the effectiveness of LID practices decreases with an increase in the return period. By applying a combined approach to a region covering approximately 10 percent of the total area of Shiraz Municipal District 4, a reduction of 2–22.8 percent in node flooding was achieved. The analysis of data mining and MCDM models with a physical model revealed that more than 60% of flooded nodes were classified as "high" and "very high" risk categories in the RF-VIKOR and RF-TOPSIS risk models.

Impact of climate change on the future distribution of three Ferulago species in Iran using the MaxEnt model.

The decline of habitats supporting medicinal plants is a consequence of climate change and human activities. In the Middle East, Ferulago angulata, Ferulago carduchorum, and Ferulago phialocarpa are widely recognized for their culinary, medicinal, and economic value. Therefore, this study models these Ferulago species in Iran using the MaxEnt model under two representative concentration pathways (RCP4.5 and RCP8.5) for 2050 and 2070. The objective was to identify the most important bioclimatic (n = 6), edaphic (n = 4), and topographic (n = 3) variables influencing their distribution and predict changes under various climate scenarios. Findings reveal slope percentage as the most significant variable for F. angulata and F. carduchorum, while solar radiation was the primary variable for F. phialocarpa. MaxEnt modeling demonstrated good to excellent performance, as indicated by all the area under the curve values exceeding 0.85. Projections suggest negative area changes for F. angulata and F. carduchorum (i.e., predictions under RCP4.5 for 2050 and 2070 indicate -34.0% and -37.8% for F. phialocarpa, and -0.3% and -6.2% for F. carduchorum; additionally, predictions under RCP 8.5 for 2050 and 2070 show -39.0% and -52.2% for F. phialocarpa, and -1.33% and -9.8% for F. carduchorum), while for F. phialocarpa, a potential habitat increase (i.e., predictions under RCP4.5 for 2050 and 2070 are 23.4% and 11.2%, and under RCP 8.5 for 2050 and 2070 are 64.4% and 42.1%) is anticipated. These insights guide adaptive management strategies, emphasizing conservation and sustainable use amid global climate change. Special attention should be paid to F. angulata and F. carduchorum due to anticipated habitat loss. Integr Environ Assess Manag 2024;20:1046-1059. © 2024 SETAC.

An integrated statistical-geospatial approach for the delineation of flood-vulnerable sub-basins and identification of suitable areas for flood shelters in a tropical river basin, Kerala

Flood vulnerability assessment is crucial for developing effective flood management and mitigation strategies. The present study aims to understand the flood vulnerability of the Kallada River Basin (KRB) and identify suitable locations for safe flood sheltering facilities in the basin. As part of this, morphometric analysis of KRB was carried out by dividing the basin into fifty-eight 4th-order sub-basins to understand the sub-basin-wise terrain characteristics and the degree of vulnerability to flooding. GIS tools were used to assess various morphometrical parameters, such as drainage frequency, texture ratio, ruggedness number, basin relief, bifurcation ratio, length of overland flow, drainage density, circularity ratio and area, and geo-environmental factors such as sand percent, rainfall, and mean slope of these basins. The morphometric parameters exhibited distinct spatial trends, with higher values primarily concentrated in the east and northeast parts for certain parameters and in the western parts for others. Using hierarchical cluster analysis, the sub-basins were categorized into six clusters, revealing that 51% were vulnerable to floods, 26% moderately vulnerable, and 22% not vulnerable. Sub-basins in the central and western KRB were found to be highly vulnerable to flooding, while those in the eastern parts showed moderate vulnerability or were not vulnerable. Flood vulnerability mapping was validated using flood data of 2018 and 2019. Additionally, the weighted overlay method identified suitable areas for flood shelters in moderately vulnerable and vulnerable sub-basins and the areas were categorized into highly suitable, suitable, moderately suitable, and not suitable areas. Most areas of SB53 and SB55 were found highly suitable, emphasizing their potential for flood shelter locations. The findings of this study can be used by competent authorities to initiate flood mitigation and to develop targeted flood preparedness measures in similar river basins, particularly in the context of increasing flood events.

The Effect of Slope Slope on the Distribution of Nickel Laterite at PT Sentratama Karya Cemerlang, South Konawe Regency, Southeast Sulawesi Province

The Morphology That Develops In The Study Area Consists Of Undulating Hills. Based On The Results Of The Slope Analysis, The Research Area Is Divided Into Several Slope Classes, Namely Flat Slopes, Gentle Slopes, Sloping Slopes And Steep Slopes. The Process Of Forming Laterite Nickel Deposits Will Be Greatly Influenced By The Slope Conditions. In The Research Area, Slopes That Have A High Percent Slope, The Thickness Of The Deposits That Will Be Formed Will Be Thinner, Ranging From 6-12 Meters, On The Other Hand, Slopes That Have A Low Percent Slope, The Thickness Of The Deposits That Will Be Formed Will Be Thicker, Ranging From 18-30 Meters. Therefore, This Study Aims To Determine The Effect Of Slope On The Distribution Of Nickel Laterite, Namely To Determine The Slope Of The Slope On Nickel Laterite At Pt Sentratama Karya Cemerlang, Laeya District, South Konawe Regency, Southeast Sulawesi Province

Evaluating land use impacts on water quality: perspectives for watershed management

Human activities threaten the integrity of watersheds. We aimed to investigate the impact of land use on water quality, adopting a multiscale approach. We collected water samples from twelve streams in Southern Brazil and conducted limnological analyses (physical, chemical, and biological) during the dry season. We used the water quality index based on the quality standards of Canada and Brazil. Land use percentage was measured in two groups (local scale and network scale). Environmental variables were summarized through Principal Component Analysis, and we organized them into Linear Models, integrating the percentage of land use classes and terrain slope in the Multifit formula. Statistical analyses were performed using the R software. Results indicated contamination by lead, chromium, copper, nitrogen, and Escherichia coli in water samples. The Canadian Water Quality Guidelines for the Protection of Aquatic Life resulted in an index ranging from 23.3 to 47.3, compared to the Brazilian Resolution No. 357/2005 for Class 2, which had an index ranging from 47.5 to 100. This disparity is attributed to the more rigorous and sensitive monitoring approach adopted by the Canadian guidelines. Riparian forests which are up to 50 m wide are associated with improved water quality. Agricultural and urban activities were the main contributors to water quality degradation in an area extending up to 1000 m from the watershed. We emphasize the importance of a multiscale approach in watershed management and public policies, considering not only riparian forest preservation, but also human activities throughout the watershed. It is crucial to prioritize science-based environmental public policies and strengthen enforcement to prevent increasingly pronounced environmental collapses. We have identified the urgency to reformulate CONAMA Resolution No. 357/2005 with a more conservationist and ecosystem-oriented approach, as well as to propose modifications to the Brazilian Forest Code, particularly regarding the buffer zones of permanent preservation areas. Thus, this study can provide insights, such as incorporating the “effect scale,” to enhance water resource management in landscapes heavily influenced by human action, contributing to the advancement of future research in freshwater ecosystems.

Kajian Nilai pH Tanah pada Berbagai Toposekuen dan Kelas Lereng yang Berbeda pada Lahan Perkebunan Karet Rakyat di Kecamatan Pelepat Ilir, Kabupaten Bungo, Jambi

Soil pH value either with KCl solution or with H2O are two important indicators needed to describe soil acidity. This study aims to determine the distribution of soil pH values in smallholder rubber plantations with different land topography classes in Pelepat Ilir Subdistrict, Bungo Regency, Jambi Province. The study used a survey method with a toposequence concept approach at a semi-detailed level, where observation points were made based on the upper tread polypedon, middle tread polypedon, and lower tread polypedon at each level of percent slope 15-24%, 8-15%, and 3-8%, and flat tread polypedon at a percent slope of 0-3%. Ten composite soils were taken from a mixture of 3 individual soil samples at each polypedon using a soil drill at a depth of 0-30 cm from the soil surface. Soil pH value analysis was conducted in the laboratory on each composite. The results showed that the pH value of the soil with 1:2 H2O solution was very acidic, and acidic for 1:2.5 KCl solution. The distribution of soil pH values showed that the lower slope had a higher pH value than the middle slope, and the upper slope had the lowest pH. Soil pH values decreased as the slope increased, and soils with flat topography were considered more fertile than those with high slopes. This result can be a recommendation in determining liming and fertilization doses, where higher doses are required for high slope soils than flat soils for optimum agricultural yields.

Kajian Nilai pH Tanah pada Berbagai Toposekuen dan Kelas Lereng yang Berbeda pada Lahan Perkebunan Karet Rakyat di Kecamatan Pelepat Ilir, Kabupaten Bungo, Jambi

Soil pH value either with KCl solution or with H2O are two important indicators needed to describe soil acidity. This study aims to determine the distribution of soil pH values in smallholder rubber plantations with different land topography classes in Pelepat Ilir Subdistrict, Bungo Regency, Jambi Province. The study used a survey method with a toposequence concept approach at a semi-detailed level, where observation points were made based on the upper tread polypedon, middle tread polypedon, and lower tread polypedon at each level of percent slope 15-24%, 8-15%, and 3-8%, and flat tread polypedon at a percent slope of 0-3%. Ten composite soils were taken from a mixture of 3 individual soil samples at each polypedon using a soil drill at a depth of 0-30 cm from the soil surface. Soil pH value analysis was conducted in the laboratory on each composite. The results showed that the pH value of the soil with 1:2 H2O solution was very acidic, and acidic for 1:2.5 KCl solution. The distribution of soil pH values showed that the lower slope had a higher pH value than the middle slope, and the upper slope had the lowest pH. Soil pH values decreased as the slope increased, and soils with flat topography were considered more fertile than those with high slopes. This result can be a recommendation in determining liming and fertilization doses, where higher doses are required for high slope soils than flat soils for optimum agricultural yields.

Sex‐specific differences and long‐term trends in habitat selection of American woodcock

AbstractEffective wildlife management requires an understanding of how individuals select environmental factors, although few studies assess how habitat selection may differ over time or between sexes. During the post‐breeding period (15 May to 1 Sep), we tracked 146 male American woodcock (Scolopax minor) in Rhode Island, USA, from 2010–2021 to assess how habitat selection varied over time, and 17 females and 51 males during the final 2 years of the study to document sex‐specific differences in habitat selection. Males generally had smaller home ranges (35.0 ± 10.7 [margin of error] ha) and preferred habitat mosaics that consisted of forested wetlands, young forest patches, areas of deciduous forest, moist soils with gentle slopes, and riparian corridors. We detected subtle differences between sexes in selection for wetland young forest, upland young forest, percent slope, distance to upland young forest, distance to streams, and distance to moist soils. During 2020–2021, females tended to have larger home ranges (78.7 ± 46.4 ha) than males (35.0 ± 10.7 ha) and more strongly selected sites closer to riparian corridors, while males selected areas that were closer to upland young forest with flatter slopes than the available surrounding landscape. Such sex‐specific differences in habitat selection may be related to males and females prospecting for potential breeding sites during this post‐breeding period for the following spring. We used the top‐ranked habitat selection models for males and females to produce a spatially explicit state‐wide map that identifies low‐to‐high likelihood of use areas that can be used to guide forest management decisions in southern New England to maximize benefits for American woodcock.

Analysis of Walkable Street Networks by Using the Space Syntax and GIS Techniques: A Case Study of Çankırı City

Nowadays, city forms are changing due to rapid urbanization and increasing population. In urban morphology studies, walkable street network is examined through the city form to create sustainable cities. This study aims to examine accessibility of street network that shapes the city form by using central street line retrieved from OSM. Accessibility of the street network, one of the criteria of walkability, was evaluated in Çankırı, a micro city in Turkey. The space syntax and GIS methods were used to examine the physical accessibility of the street network. As differences in the topography are not taken into consideration in the space syntax, it was integrated with the GIS in this study. With this method, spatial accessibility, the correlation between integration and choice values of street network, was examined at first. Secondly, land slope was classified according to the standards of pedestrian accessibility and the study area was analyzed using the GIS. Finally, streets with low slope percentage and high integration value were overlaid. The results revealed that the longest, continuous, and main axes located in the area with low slope and high integration values are accessible. The accessible streets obtained by a collaborative integration of the space syntax and GIS methods are lower than the area obtained just from the space syntax method. The use of a combination of these methods is beneficial in terms of understanding the land in three dimensions, but focusing on land surface slopes is only one of the possible synergies between the two tools. The walkable street network obtained by using this method gives an idea about urban mobility. While this method works with hilly lands, other GIS data may be needed for different land types. However, it should also be extended to multi-source information and quantitative analysis methods in bigger cities, as urban walkability is at the core of the 15-minute city model, which is of high actuality of the agenda of urban planning and sustainable urban development.

Impact of Topography on Rural Cycling Patterns: Case Study of Bugesera District, Rwanda

Rural mobility in Africa is an under-researched issue. Rural communities have often suffered from reduced mobility that has hampered their access to essential services and facilities such as education, health care, food, and clean water. In many rural communities, a more affordable mobility option, such as non-motorized mobility (cycling and walking), is the preferred way for people to travel. Apart from its well-known advantages, little is known about the impact of topography and routes on the mobility options adopted by rural communities. Therefore, this study aims to use Digital Elevation Models (DEMs) to analyze the impact of topography and routes on rural mobility patterns at the level of formal and informal cycle track networks in the Bugesera District, focusing on the Nyamata and Mayange sectors, Rwanda. This study used GPS devices given to 50 participants to collect mobility patterns in the two previously mentioned sectors. Then, the study imposed a 30-m buffer on the official road networks of Rwanda collected by the Rwanda Transport Development Agency (RTDA). These data were joined to GPS tracks to highlight official and unofficial roads (tracks that did not fall within the 30-m buffer). In addition, Digital Elevation Models were applied to analyze the SRTM (30 m resolution) and ALOS PALSAR (12.5 m resolution) elevation data of the Bugesera region. The findings revealed an elevation range of 1333 to 1535 for SRTM and 1323 to 1641 for ALOS PALSAR. The study calculated the slope to find the slope percentage (m) and length (m). The findings from the DEMs and the slope calculation revealed that Bugesera has a relatively flat surface, favorable for cycling. The slope percentage was further classified into five levels of slope ranging from steep to very steep. And the Van Zuidam classification results confirmed that Bugesera has “a flat or nearly flat surface, without significant denudation processes”. With a favorable topography and a higher bicycle ownership ratio, residents of the Bugesera district favor cycling in their daily activities more than any district in Rwanda. Cycling in Nyamata or Mayange links residents to areas with higher social, educational, administrative, and economic activities.

Evaluating the impact of prescribed surface fire on seedlings in the Central Hardwood Region, USA

Abstract Oak (Quercus) is being successionally replaced by maple (Acer) across much of the eastern deciduous forest. Past research on the close relationship between oak and fire has led forest managers to use prescribed surface fires to deter this replacement. However, there has not been a comprehensive evaluation of the effectiveness of prescribed fire by managers, particularly in the Central Hardwood Region. For example, it is not known how many repeat applications of prescribed fire are needed to accumulate enough oak reproduction to successfully re-establish oak-dominated stands. Tree reproduction and midstory composition were systematically surveyed across 63 mature, oak-dominated stands ranging in prescribed fire histories and aspects on the Hoosier and Wayne National Forests in southern Indiana and Ohio, respectively. These stands represent the vast majority of stands burned to promote oak regeneration since 1990 in these two National Forests. Across all sites, seedlings in the white oak group (section Quercus) and red oak group (section Lobatae) comprised 47.8 ± 3.3 per cent and 8.2 ± 1.6 per cent (mean ± SE), respectively, of all seedlings. In comparison, common competing species (maples and American beech) comprised 5.4 ± 1.4 per cent of all seedlings. Mid- and overstory basal area, percent slope, years since last burn, and total number of burns significantly affected oak seedling density. Greater increases in taller, competitive oak seedling density occurred after sites had been burned three times and with high frequency (≤4 years between burns). However, results also suggest that if an established midstory already exists or fire has not been used on the landscape for almost a decade, repeat applications of prescribed fire will not likely increase oak regeneration in the short term without concurrent treatment of midstory stems.

Remote sensing applied to geological, structural, and mass movements characterization in the connection between Curral Homocline and Moeda Syncline, Quadrilátero Ferrífero Region, Brazil

Mass movements naturally occurring along slopes, especially after heavy rains, cause heavy losses of materials and life and affect highways, pipelines, and bridges, among other structures. Among the most common mass movements, landslides and subsequent mass flows especially stand out. Remote sensing and geoprocessing techniques are useful tools for geological and geotechnical analysis, here applied to characterization of mass movements from the analysis of the influence of slopes, lineaments or fractures, and geological-geotechnical at the junction of the Curral homocline and the Moeda syncline, Quadrilátero Ferrífero, Southeast Brazil. The area consists of Archean granitic-gneissic basement and the greenstone belt sequence of the Rio das Velhas Supergroup with Proterozoic metasedimentary rocks of the Minas Supergroup covering these two older successions. Based on satellite images, a preliminary map of lineaments was created, and fractures were grouped according to their direction before being rasterized. Each lineament group was associated with a previously known geological and/or structural feature. Geological units mapped in the area were numerically classified according to their mass movement susceptibility and related geotechnical units. Using a Shuttle Radar Topography Mission (SRTM) image, a terrain slope raster was generated. The objective was to obtain a raster indicating low and high probabilities of mass movements. Four sets of lineaments were identified: the first set associated with the northeast strike stratification of the rocks of the Moeda Formation; the second set related to eastward-trending warp axis lineations; the third set related to the southeast trend of stretch lineaments or mafic dykes directions; and the fourth set evidently associated with the watershed pattern of the Curral Range crest, perpendicular to the strike of the rocks in the area. Simulations with different combinations of parameters produced eight scenarios were generated were constructed to classify the area as to its susceptibility to rupture through changes in slope, lithotype, and lineament density; the first four (1 to 4) were classified by using the slope percentage raster without interval reclassification, so its values in the cartographic algebra were not grouped. The last for (5 to 8), consider the slope percentage classified. This methodology successfully combines mathematical models for predicting mass movements and determining areas in the urban landscape most susceptible to these phenomena. As such, it comprises a useful tool for government planning of preventative actions for areas of high risk.

ОЦІНКА ЕКОНОМІЧНОЇ ЕФЕКТИВНОСТІ ВІД ВПРОВАДЖЕННЯ СИСТЕМИ ТОЧНОГО ЗЕМЛЕРОБСТВА

The work describes modern methods and methods of determining the terrain and assessing its economic effect, which include the use of the global positioning system (GPS): with the help of satellite navigation, it is possible to establish an exact position in real time and collect data on the height of points on the field, this data can be used to determine the angle of inclination of the surface; laser scanning: laser scanners that scan the surface of the field and create an accurate three-dimensional model of the relief, which will, among other things, contain information about the angles of inclination of the surface in different parts of the field can be used in STZ; differential geodesy: with the help of special geodetic tools, you can determine the angle of inclination and create a digital model of the terrain; and Remote Sensing: Remote sensing, such as satellite imagery or aerial photography, can also be used in STPs to analyze field topography. With the help of special software, you can process these images and determine the angle of inclination of different sections of the field. The problems of increasing the efficiency of the use of land within the framework of agricultural land use, taking into account the system of precision farming in the process of intensification of agricultural production, are a component of the unified state ecological and economic policy, which ensures the rational use, protection and management of land resources, as well as the formation of information about their natural, legal and economic condition. The general level of growth of costs for cultivation of 1 hectare of field when the slope increases from 2 to 15% varies from 7.6% to 11.38%, depending on the machine unit. An increase in field surface slope between 0% and 20% results in a modest increase in direct operating costs, averaging 0.766%, for each successive percent of slope. According to the obtained data, processing a field with a relief of 15%, relative to a field with a relief of 2%, leads to an increase in the consumption of fuel and fuel-lubricating materials on average, for 5 units of different composition, by 45.5 and 48%, respectively. Other indicators deteriorate by an average of 1.66 – 3.88%. All this, as a result, leads to a significant increase in the direct operating costs of the machine unit for processing one hectare of field.

Collective Effects of Fire Intensity and Sloped Terrain on Wind-Driven Surface Fire and Its Impact on a Cubic Structure

The combined effects of percent slope and fire intensity of a wind driven line fire on an idealized building has been numerically investigated in this paper. The simulations were done using the large eddy simulation (LES) solver of an open source CFD toolbox called FireFOAM. A set of three fire intensity values representing different heat release rates of grassland fuels on different inclined fuel beds have been modeled to analyze the impact of factors, such as fuel and topography on wind-fire interaction of a built area. An idealized cubic structure representing a simplified building was considered downstream of the fire source. The numerical results have been verified with the aerodynamic measurements of a full-scale building model in the absence of fire effects. There is a fair consistency between the modeled findings and empirical outcomes with maximum error of 18%, which acknowledge the validity and precision of the proposed model. The results show that concurrent increase of fire intensity and terrain slope causes an expansion of the surface temperature of the building which is partially due to the increase of flame tilt angle upslope on the hilly terrains. In addition, increasing fire intensity leads to an increase in the flow velocity, which is associated with the low-pressure area observed behind the fire front. Despite limitations of the experimental results in the area of wind-fire interaction the result of the present work is an attempt to shed light on this very important problem of fire behavior prediction. This article is a primary report on this subject in CFD modeling of the collective effects of fire intensity and sloped terrain on wind driven wildfire and its interaction on buildings.

Vulnerability analysis of urban texture in earthquakes: A case study of District 2 of Tabriz city

Introduction: Natural disasters are known as one of the most important factors in the destruction of human settlements. One of the key concerns for urban planners is examining how natural disasters affect human settlements, particularly cities. Earthquake is one of these natural disasters that has always threatened human settlements and can cause a lot of damage and casualties in a short period. Therefore, this study aimed to assess the vulnerability of settlements in District 2 of Tabriz, Iran, against earthquakes. Methods: This applied research was conducted based on a descriptive-analytical approach. The primary data of existing documents and maps were collected from related organizations. The analytical hierarchy process model and geographic information system software were used for data analysis. Findings: To determine the vulnerability of the texture of District 2 of Tabriz, such indicators as the distance from the fault, slope percentage, groundwater levels, building age, building materials, building quality, building density, number of floors, plot area, and land use were employed. Conclusion: According to the results, 35% of the region was in the high-risk and 25% in the very high-risk areas. In general, it can be said that most of the region (i.e. 60%) was in the area with a high risk of earthquake, and the area with very high risk was mostly in the northern parts of the region, while the southeastern parts of the region were located in low-risk areas.