scholarly journals Topo-edaphic, Vegetation Cover and Type Influence on Spatial Distribution of Gullies in Sengwa Wildlife Research Area (SWRA), North West Zimbabwe

2021 ◽  
Vol 4 (4) ◽  
pp. 61-73
Author(s):  
Mahakata I. ◽  
Hungwe C. ◽  
Ngoni M. ◽  
Matindike S. ◽  
Gonhi P. ◽  
...  

Gully erosion is a common phenomenon in arid and semi-arid areas and is mostly influenced by soil type, topography, vegetation type and cover. The objective of the study was to determine the effect of topo-edaphic, vegetation type and cover on gully occurrence, hence map their spatial distribution in SWRA. A conventional method was used where field visit to known gully sites was done. At each site, GPS points were marked at three points, that is, at the head site, the middle and lower end of the gully. Soil samples, gully width, depth, length, vegetation type and cover were recorded for each point where GPS coordinates were collected. GPS points were overlaid on SWRA processed vegetation, soil and topographic map for analysis on the spatial distribution of gullies. Fifty-six gullies were recorded with highly affected areas on the southwestern side of the park. Associated soils types were clay and loam of the Madumabisa mudstone, colluvial and alluvial located at altitudes below 1000 meters. Gully occurrences were sighted more in mopane dominated woodlands with few recorded in areas dominated by acacia woodlands and on the edges of miombo woodlands, which occupy the high grounds of SWRA. Gully length varied from 20m in less developed gullies to 2520m for mature gullies with volumes ranging between 52m3 and 4649.4m3. Hence, topography, soil type, vegetation cover and type influence gully location and occurrence. Future research should aim to monitor changes in gully development using remote sensing as it provides a great potential for monitoring gully changes across the landscape.

2020 ◽  
Vol 4 (2) ◽  
pp. 780-787
Author(s):  
Ibrahim Hassan Hayatu ◽  
Abdullahi Mohammed ◽  
Barroon Ahmad Isma’eel ◽  
Sahabi Yusuf Ali

Soil fertility determines a plant's development process that guarantees food sufficiency and the security of lives and properties through bumper harvests. The fertility of soil varies according to regions, thereby determining the type of crops to be planted. However, there is no repository or any source of information about the fertility of the soil in any region in Nigeria especially the Northwest of the country. The only available information is soil samples with their attributes which gives little or no information to the average farmer. This has affected crop yield in all the regions, more particularly the Northwest region, thus resulting in lower food production.  Therefore, this study is aimed at classifying soil data based on their fertility in the Northwest region of Nigeria using R programming. Data were obtained from the department of soil science from Ahmadu Bello University, Zaria. The data contain 400 soil samples containing 13 attributes. The relationship between soil attributes was observed based on the data. K-means clustering algorithm was employed in analyzing soil fertility clusters. Four clusters were identified with cluster 1 having the highest fertility, followed by 2 and the fertility decreases with an increasing number of clusters. The identification of the most fertile clusters will guide farmers on where best to concentrate on when planting their crops in order to improve productivity and crop yield.


1995 ◽  
pp. 3-21
Author(s):  
S. S. Kholod

One of the most difficult tasks in large-scale vegetation mapping is the clarification of mechanisms of the internal integration of vegetation cover territorial units. Traditional way of searching such mechanisms is the study of ecological factors controlling the space heterogeneity of vegetation cover. In essence, this is autecological analysis of vegetation. We propose another way of searching the mechanisms of territorial integration of vegetation. It is connected with intracoenotic interrelation, in particular, with the changing role of edificator synusium in a community along the altitudinal gradient. This way of searching is illustrated in the model-plot in subarctic tundra of Central Chukotka. Our further suggestion concerns the way of depicting these mechanisms on large-scale vegetation map. As a model object we chose the catena, that is the landscape formation including all geomorphjc positions of a slope, joint by the process of moving the material down the slope. The process of peneplanation of a mountain system for a long geological time favours to the levelling the lower (accumulative) parts of slopes. The colonization of these parts of the slope by the vegetation variants, corresponding to the lowest part of catena is the result of peneplanation. Vegetation of this part of catena makes a certain biogeocoenotic work which is the levelling of the small infralandscape limits and of the boundaries in vegetation cover. This process we name as the continualization on catena. In this process the variants of vegetation in the lower part of catena are being broken into separate synusiums. This is the process of decumbation of layers described by V. B. Sochava. Up to the slope the edificator power of the shrub synusiums sharply decreases. Moss and herb synusium have "to seek" the habitats similar to those under the shrub canopy. The competition between the synusium arises resulting in arrangement of a certain spatial assemblage of vegetation cover elements. In such assemblage the position of each element is determined by both biotic (interrelation with other coenotic elements) and abiotic (presence of appropriate habitats) factors. Taking into account the biogeocoenotic character of the process of continualization on catena we name such spatial assemblage an exolutionary-biogeocoenotic series. The space within each evolutionary-biogeocoenotic series is divided by ecological barriers into some functional zones. In each of the such zones the struggle between synusiums has its individual expression and direction. In the start zone of catena (extensive pediment) the interrelations of synusiums and layers control the mutual spatial arrangement of these elements at the largest extent. Here, as a rule, there predominate edificator synusiums of low and dwarfshrubs. In the first order limit zone (the bend of pediment to the above part of the slope) one-species herb and moss synusiums, oftenly substituting each other in similar habitats, get prevalence. In the zone of active colonization of slope (denudation slope) the coenotic factor has the least role in the spatial distribution of the vegetation cover elements. In particular, phytocoenotic interactions take place only within separate microcoenoses of herbs, mosses and lichens. In the zone of the attenuation of continualization process (the upper most parts of slope, crests) phytocoenotic interactions are almost absent and the spatial distribution of vegetation cover elements depends exclusively on the abiotic factors. The principal scheme of the distribution of vegetation cover elements and the disposition of functional zones on catena are shown on block-diagram (fig. 1).


2002 ◽  
pp. 32-43
Author(s):  
V. I. Vlasenko ◽  
M. G. Erunova ◽  
I. S. Scerbinina

The reserve “Stolby” is characteristic key plot of the mountain-taiga and subtaiga-forest steppe altitudinal belts in the East Sayan Mountains, where anthropogenic influence is the least pronounced. It was founded in 1925, in 15 km southward of Krasnoyarsk city, on north-west spurs of the Western Sayan Mountains which adjoin closely to right bank of the Yenisei River bordering upon the Middle Siberian Plateau. Reserve's physiography is characterized by low mountain and middle mountain erosion-accumulation relief with absolute heights of 200-800 m. Low mountain part (200-500 m) is composed of loose sedimentary rocks. In the middle mountain part of the reserve (500-800 m) there are outcrops of sienite rocks of various stages of destruction. Vegetation and soils of the reserve change in agreement with absolute heights and climate. In low mountains spread the subtaiga and forest-steppe leaved-light needle forests on mountain grey forest soils (8.1 % of reserve territory); the middle mountain part is occupied by the light needle and dark needle taiga forests on mountain podzol soils (91.9 % of the area). As the basement for vegetation map we took the map of forest environments of reserve by T. N. Butorina compiled according to materials of land forest management of 1977 year. As the result of forest management near 2000 biogeocoenoses were distinguished. The type of biogeocoenosis, according to V. N. Sukachev, is selected as mapping unit. Biogeocoenoses were united into 70 groups of forest types, representing 21 series of associations which are reflected in the map legend (Fig. 1). The main goal of map is to show the territorial distribution of groups and series of types of biogeocoenoses in the main structural units - altitudinal be't complexes (ВПК) which are equivalents of altitudinal vegetation belts. For designation of forest tree species various kinds of hatches were used. Formations of Siberian pine, larch, pine, fir, spruce, birch and aspen forests are shown on the map. Within the ВПК arabic numerals show the groups of types of biogeocoenoses (forest types), united into series according to similarity of dominants in ground layer. The mountain-taiga ВПК includes the following series and groups of types of biogeocoenoses: dwarf-shrub-moss (1-4); sedge-moss (5-9); bilberry-low herb-moss (10-14); tall herb-sedge (15-19); tall herb-wood sour-moss (20-26); tall herb-small reed (27-32). The subtaiga-forest steppe ВГ1К embraces: shrub steppificated (33-34); shrub-forb steppificated (35-38): sedge- bilberry (39-40); sedge-forb (41-43); bracken (44); small reed-forb (45); bilberrv-forb- sedge (46, 47); forb-tall herb (48-51); tall herb (52-55); wet tall herb-small reed (56-59); fern-tall herb (60). Intrazonal phytocoenoses: brook tall herb (61-63); brook shrub (64-68); lichen-moss (69); cowberry (70). In 1999-2000 on the base of topographic map in a scale 1 : 25 000, map of forest environments, transformed by us into vegetation map of the reserve, M. J . Erunova and I. S. Scerbinina worked out an electronic variant. For this project the instrumental facilities of GIS, GeoDraw and GeoGraph (CGI IG RAS, Moscow) and programs of Geophyt were used.


Author(s):  
Jyoti Sharma ◽  
Lata Raj ◽  
Anil Gupta

The purpose of this study is to measure the existence of co-creation behavior between doctors and patients. The research also studies customer participation and customer citizenship behavior as the dimensions of co-creative behavior and tries to establish the relationship between co-creative behavior and satisfaction. This study uses Yi and Gong (2013) scale for collecting data regarding co-creation behavior and its dimensions which are customer participation (CP) and customer citizenship behavior (CCB). The data was collected from 204 patients who were suffering from various chronic/lifestyle diseases and getting their treatment from private clinics in Jammu city. The study uses 7-point Likert scale in the questionnaire ranging from 1 completely disagree through 7 completely agree, with a midpoint labeled 4 neither agree nor disagree. The analysis of paper reflects that co-creation behavior is prevalent among the patients and not only participation but the citizenship behavior also affects the co-creation behavior of patients. The study is conducted from patients point of view whereas doctors perspective should also be used in future research. The research area is restricted to Jammu city only. The research provides several implications-doctors can also use this scale for market segmentation and customer profiling for maximizing customer value co-creation behavior by gaining the useful information.


2021 ◽  
Vol 13 (12) ◽  
pp. 6976
Author(s):  
Dimitrios E. Alexakis ◽  
George D. Bathrellos ◽  
Hariklia D. Skilodimou ◽  
Dimitra E. Gamvroula

Karst features such as polje are highly vulnerable to natural and anthropogenic pollution. The main objectives of this study were to investigate the soil quality in the Ioannina polje (north-west Greece) concerning arsenic (As) and zinc (Zn), and delineate their origin as well as compare the As and Zn content in soil with criteria recorded in the literature. For this purpose, the geomorphological settings, the land use, and the soil physicochemical properties were mapped and evaluated, including soil texture and concentrations of aqua-regia extractable As and Zn. The concentration of elements was spatially correlated with the land use and the geology of the study area, while screening values were applied to assess land suitability. The results reveal that 72% of the total study area has a very gentle slope. This relief favors urban and agricultural activity. Thus, the urban and agricultural land used cover 92% of the total area. The spatial distribution for As and Zn in the soil of the study area is located on very gentle slopes and is strongly correlated with the geological parent materials and human-induced contamination sources. Arsenic and Zn can be considered enriched in the soil of the area studied. The median topsoil contents (in mg kg−1) for As (agricultural soil 16.0; urban soil 17.8) and Zn (agricultural soil 92.0; urban soil 95.0) are higher compared to the corresponding median values of European topsoils. Land evaluation suitability concerning criteria given from the literature is discussed. The proposed work may be helpful in the project of land use planning and the protection of the natural environment.


Processes ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 21
Author(s):  
Brigitte Altmann ◽  
Christoph Grün ◽  
Cordula Nies ◽  
Eric Gottwald

In this second part of our systematic review on the research area of 3D cell culture in micro-bioreactors we give a detailed description of the published work with regard to the existing micro-bioreactor types and their applications, and highlight important results gathered with the respective systems. As an interesting detail, we found that micro-bioreactors have already been used in SARS-CoV research prior to the SARS-CoV2 pandemic. As our literature research revealed a variety of 3D cell culture configurations in the examined bioreactor systems, we defined in review part one “complexity levels” by means of the corresponding 3D cell culture techniques applied in the systems. The definition of the complexity is thereby based on the knowledge that the spatial distribution of cell-extracellular matrix interactions and the spatial distribution of homologous and heterologous cell–cell contacts play an important role in modulating cell functions. Because at least one of these parameters can be assigned to the 3D cell culture techniques discussed in the present review, we structured the studies according to the complexity levels applied in the MBR systems.


2021 ◽  
Vol 13 (15) ◽  
pp. 2935
Author(s):  
Chunhua Qian ◽  
Hequn Qiang ◽  
Feng Wang ◽  
Mingyang Li

Building a high-precision, stable, and universal automatic extraction model of the rocky desertification information is the premise for exploring the spatiotemporal evolution of rocky desertification. Taking Guizhou province as the research area and based on MODIS and continuous forest inventory data in China, we used a machine learning algorithm to build a rocky desertification model with bedrock exposure rate, temperature difference, humidity, and other characteristic factors and considered improving the model accuracy from the spatial and temporal dimensions. The results showed the following: (1) The supervised classification method was used to build a rocky desertification model, and the logical model, RF model, and SVM model were constructed separately. The accuracies of the models were 73.8%, 78.2%, and 80.6%, respectively, and the kappa coefficients were 0.61, 0.672, and 0.707, respectively. SVM performed the best. (2) Vegetation types and vegetation seasonal phases are closely related to rocky desertification. After combining them, the model accuracy and kappa coefficient improved to 91.1% and 0.861. (3) The spatial distribution characteristics of rocky desertification in Guizhou are obvious, showing a pattern of being heavy in the west, light in the east, heavy in the south, and light in the north. Rocky desertification has continuously increased from 2001 to 2019. In conclusion, combining the vertical spatial structure of vegetation and the differences in seasonal phase is an effective method to improve the modeling accuracy of rocky desertification, and the SVM model has the highest rocky desertification classification accuracy. The research results provide data support for exploring the spatiotemporal evolution pattern of rocky desertification in Guizhou.


Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 647
Author(s):  
Mohamed Saiful Firdaus Hussin ◽  
Aludin Mohd Serah ◽  
Khairul Azri Azlan ◽  
Hasan Zuhudi Abdullah ◽  
Maizlinda Izwana Idris ◽  
...  

Collecting information from previous investigations and expressing it in a scientometrics study can be a priceless guide to getting a complete overview of a specific research area. The aim of this study is to explore the interrelated connection between alginate, gelatine, and hydroxyapatite within the scope of bone tissue and scaffold. A review of traditional literature with data mining procedures using bibliometric analyses was considered to identify the evolution of the selected research area between 2009 and 2019. Bibliometric methods and knowledge visualization technologies were implemented to investigate diverse publications based on the following indicators: year of publication, document type, language, country, institution, author, journal, keyword, and number of citations. An analysis using a bibliometric study found that 7446 papers were located with the keywords “bone tissue” and “scaffold”, and 1767 (alginate), 185 (gelatine), 5658 (hydroxyapatite) papers with those specific sub keywords. The number of publications that relate to “tissue engineering” and bone more than doubled between 2009 (1352) and 2019 (2839). China, the United States and India are the most productive countries, while Sichuan University and the Chinese Academy of Science from China are the most important institutions related to bone tissue scaffold. Materials Science and Engineering C is the most productive journal, followed by the Journal of Biomedical Materials Research Part A. This paper is a starting point, providing the first bibliometric analysis study of bone tissue and scaffold considering alginate, gelatine and hydroxyapatite. A bibliometric analysis would greatly assist in giving a scientific insight to support desired future research work, not only associated with bone tissue engineering applications. It is expected that the analysis of alginate, gelatine and hydroxyapatite in terms of 3D bioprinting, clinical outcomes, scaffold architecture, and the regenerative medicine approach will enhance the research into bone tissue engineering in the near future. Continued studies into these research fields are highly recommended.


2021 ◽  
Vol 1 ◽  
pp. 3101-3110
Author(s):  
Carl Nils Konrad Toller ◽  
Marco Bertoni

AbstractProduct-Service Systems (PSS) have emerged as a key concept to meet the societal and market trends of increasing customer needs through the entire life-cycle. Unfortunately, several companies are struggling with getting revenues from service investments and translating 'real needs' to design improvements. The demand of the designer to go beyond the Voice of the Customer (VoC) is evident. This paper aims to map the interventions proposed by research in the area of PSS and VoC. Using a systematic mapping approach, the research domain was analyzed with regards to context and interventions. The results show a progressive development in the research area with a focus on the specification and realization of needs. A gap exists in connecting the engineers with 'real needs' and integrating the customer as a natural part of the entire development cycle of a PSS. By performing a systematic mapping, future research can be more focused and hopefully increasing its impact.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Sonal Thukral ◽  
Apoorva Jain

Purpose For sustaining a competitive advantage in the integrated world economy, it has become imperative for family firms to internationalise their operations in overseas markets. However, despite the growing set of literature, results are still inconclusive with respect to family firms’ internationalisation. Thus, this study aims to address this gap by systematically reviewing 142 articles (1991–2019) to help researchers in identifying and unfolding the unexplored themes in the underlying area. Design/methodology/approach For systematically reviewing articles, the study uses a three-step methodology following PRISMA guidelines, bibliometric analysis and thematic analysis. Descriptive statistics of 142 research articles are obtained through bibliometric analysis while thematic analysis is carried out to create themes or clusters of various factors relating to family firms’ internationalisation. Findings The current review uncovers the evolving trends in the research streams, most productive authors, top journals and articles, co-citation analysis, as well as the major themes surrounding the family firms’ internationalisation literature. Results from bibliometric analysis indicate that family firms’ internationalisation is an upcoming research area. Also, the review indicates an opportunity for scholars from developing nations to make significant contributions in the underlying research stream. Research limitations/implications Results from bibliometric and thematic analysis will help academicians and researchers in accumulating a holistic understanding relating to family firms’ internationalisation and understanding the upcoming trends in family firms’ research, thereby guiding the future research scope. Also, it will assist the family firms’ leaders and managers in understanding the important dynamics in overseas markets and various factors to be considered while planning their internationalisation. Originality/value Undertaking a systematic literature review presents readers with a state-of-the-art understanding of the underlying research topic. To the best of the knowledge, to date, the study is the first to conduct the review of literature through bibliometric analysis with the help of R Studio software in the field of family firms’ internationalisation. Also, the study is the first to review more than 100 research articles in the underlying area. Finally, the study proposes a comprehensive framework integrating the major themes and facets relating to family firms’ internationalisation.


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