Spatial distribution of manganese in vegetation cover in the proximity of an abandoned manganese oxide mine and implications for future agricultural development in the region

2005 ◽  
Vol 13 (3) ◽  
pp. 267-273 ◽  
Author(s):  
Georges Ekosse ◽  
Paul S. Fouche
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).


2012 ◽  
Vol 64 (3) ◽  
pp. 971-980 ◽  
Author(s):  
Ewa Zurawska-Seta ◽  
T. Barczak

European moles are widespread in both cultivated and uncultivated areas in Poland. Their occurrence and distribution in relation to the physical and chemical characteristics of soil has been already studied in previous research. However, there is still an open question about the impact of the structure of anthropogenic habitats produced by agriculture on moles. The main aim of this study is to assess the influence of different kinds of field margins on the presence and spatial distribution of the European mole Talpa europaea L. in farmlands. Methods included the monitoring of six investigative sites in northern Poland. Observations were made during three six-month periods in 2005-2008 of the presence or absence of moles as recognized by recent molehills and surface tunnels. There was a very clear tendency by moles to occupy areas within arable fields close to field boundaries with wide verges containing ruderal and woodland communities with a spacious zone of ecotones. Narrow boundary strips were avoided by moles. In conclusion, the conducted research confirms that field margins have an impact on the presence and spatial distribution of moles within ploughed lands. Our results may be helpful in improving the relation between agricultural development and biodiversity conservation, and the rational use of nature by humankind.


2012 ◽  
Vol 13 (1) ◽  
pp. 12 ◽  
Author(s):  
H. EL LAKHRACH ◽  
A. HATTOUR ◽  
O. JARBOUI ◽  
K. ELHASNI ◽  
A.A. RAMOS-ESPLA

The aim of this paper is to bring to light the knowledge of marine diversity of invertebrates in Gabes gulf. The spatial distribution of the megabenthic fauna community in Gabes gulf (Tunisia, Eastern Mediterranean Sea), together with the bottom type and vegetation cover, were studied. The abundance of the megabenthic fauna was represented by eight groups: Echinodermata (38%), Crustacea (21%), Tunicata (19%), Mollusca (13%), Porifera (4%), Cnidaria (3%), Bryozoa, and Annelida (2%). It was spatially more concentrated in the coast area of the gulf than in the offshore waters. This area, especially, in Southern Kerkennah, North-est of Gabes and North-east of Djerba appeared to be in a good ecological condition  hosting a variety of species like the paguridsPaguristes eremita and Pagurus cuanensis, the brachyura Medorippe lanata, Inachus doresttensis, the Gastropoda Hexaplex trunculus, Bolinus brandaris, Aporrhais pespelecani, andErosaria turdus, the Bivalvia Fulvia fragilis, the Echinoidea Psammechinus microtuberculatus, Holothuria polii,Ophiothrix fragilis and Antedon mediterranea, and the AscidiaceaAplidium cf. conicum, Didemnum spp, and Microcosmus exasperatus.The species’ compositions of the megabentic fauna community showed clearly that the spatial analysis represented the differences between the community of these two regions (inshore waters and offshore waters). These differences were closely related to peculiar characters of the fauna and biotopes (depth, bottom type and vegetation cover community). The results of the present study should be considered as a necessary starting point for a further analysis of priceless benthic fauna contribution to the marine environment and its organisms.


2018 ◽  
Vol 12 (1) ◽  
pp. 10-22 ◽  
Author(s):  
Shwan O. Hussein ◽  
Ferenc Kovács ◽  
Zalán Tobak ◽  
Haidi J. Abdullah

Green spaces are playing an essential role for ecological balance and for human health in the city as well.They play a fundamental role in providing opportunities for relaxation and enjoying the beauty of naturefor the urban population. Therefore, it is important to produce detailed vegetation maps to assist plannersin designing strategies for the optimisation of urban ecosystem services and to provide a suitable planfor climate change adaptation in one fast growing city. Hence, this research is an investigation using 0.5m high-resolution multispectral Pléiades data integrated with GIS data and techniques to detect andevaluate the spatial distribution of vegetation cover in Erbil City. A supervised classification was usedto classify different land cover types, and a normalised difference vegetation index (NDVI) was usedto retrieve it for the city districts. Moreover, to evaluate the accessibility of green space based on theirdistance and size, a buffer zone criterion was used. The results indicate that the built-up land coverageis 69% and vegetation land cover is 14%. Regarding NDVI results, the spatial distribution of vegetationcover was various and, in general, the lowest NDVI values were found in the districts located in the citycentre. On the other hand, the spatial distribution of vegetation land cover regarding the city districts wasnon-equal and non-concentric. The newly built districts and the districts far from the Central BusinessDistrict (CBD) recorded the lowest vegetation cover compared with the older constructed districts.Furthermore, most of the districts have a lack of access to green spaces based on their distance and size.Distance and accessibility of green areas throughout the city are not equally distributed. The majority ofthe city districts have access to green areas within radius buffer of two kilometres, whereas the lowestaccessibility observed for those districts located in the northeast of the city in particular (Xanzad,Brayate, Setaqan and Raperin). Our study is one of the first investigations of decision-making supportof the spatial planning in a fast-growing city in Iraq and will have a utilitarian impact on developmentprocesses and local and regional planning for Erbil City in the future.


2015 ◽  
Vol 45 (1) ◽  
pp. 125-134 ◽  
Author(s):  
Kirill Korznikov

Mud volcano vegetation is not well-studied even in comparison with that of geothermal areas. Mud volcanoes provide opportunities to study the formation of the spatial and species structure of vegetation cover in distinct conditions, showing the trends in vegetation succession. The mud fields of the Maguntan mud volcano (Sakhalin, Russia) are cool, not warm, and their mud fluids have high salinity and alkalinity. In the 20th century some local endemic taxa were found at this place: Artemisia limosa, Gentianella sugawarae, Primula sachalinensis and Deschampsia tzvelevii. I identified nine plant communities and analyzed floristic richness, vegetation cover and endemism rate using data from 185 1 m × 1 m quadrats. The salinity decreases with distance from the volcano's main eruptive center. The total plant cover, number of plant species, and floristic richness increase with the distance from the volcano's center. Endemic taxa including the local endemic grass species Deschampsia tzvelevii are located in young mud substrates. Detrended correspondence analysis showed that the plant communities are arranged along a stress gradient. The spatial distribution of plant communities may be interpreted via succession dynamics.


Author(s):  
Kun ZHANG ◽  
Yihe LÜ ◽  
Bojie FU ◽  
Ting LI

ABSTRACTSince the ‘Grain to Green Program' was launched in 1999 in the Loess Plateau, China, the processes and patterns of ecological change have become important. Through the use of the fractional vegetation cover (FVC) index, this study examines the spatial distribution and temporal change of vegetation cover in the Loess Plateau during 2000–2014. Over this period more than 60% of the Loess Plateau has remained with little vegetation cover (FVC <30%). The spatial distribution pattern shows an overall increase from the NW to SE. Temporally, the vegetation cover exhibits a general trend of improvement. In 2000–2005, 2000–2010 and 2000–2014, the percentages of restored vegetation (vegetation with significantly increased FVC, P<0.05) were 2, 21 and 52%, respectively. The rate of vegetation cover restoration was highly variable among different bioclimatic zones. The expansion of restored vegetation was greater in the N of the Loess Plateau than in the south. Both human restoration activities and climatic fluctuation influenced the vegetation cover change. The ‘Grain to Green Program' emphasised vegetation restoration. Regional precipitation also had clear effects on vegetation cover. The results of this study reveal that vegetation change shows a non-linear process in response to climate and ecological restoration measures, and that the change gradually emerges over time. This study highlights the importance of considering the spatiotemporal variability in vegetation cover during the implementation of restoration programs, which could aid decision-making for the effective and sustainable management of large-scale restoration programs.


Sensors ◽  
2019 ◽  
Vol 19 (3) ◽  
pp. 589 ◽  
Author(s):  
Shuai Huang ◽  
Jianli Ding ◽  
Jie Zou ◽  
Bohua Liu ◽  
Junyong Zhang ◽  
...  

Soil moisture is an important aspect of heat transfer process and energy exchange between land-atmosphere systems, and it is a key link to the surface and groundwater circulation and land carbon cycles. In this study, according to the characteristics of the study area, an advanced integral equation model was used for numerical simulation analysis to establish a database of surface microwave scattering characteristics under sparse vegetation cover. Thus, a soil moisture retrieval model suitable for arid area was constructed. The results were as follows: (1) The response of the backscattering coefficient to soil moisture and associated surface roughness is significantly and logarithmically correlated under different incidence angles and polarization modes, and, a database of microwave scattering characteristics of arid soil surface under sparse vegetation cover was established. (2) According to the Sentinel-1 radar system parameters, a model for retrieving spatial distribution information of soil moisture was constructed; the soil moisture content information was extracted, and the results were consistent with the spatial distribution characteristics of soil moisture in the same period in the research area. (3) For the 0–10 cm surface soil moisture, the correlation coefficient between the simulated value and the measured value reached 0.8488, which means that the developed retrieval model has applicability to derive surface soil moisture in the oasis region of arid regions. This study can provide method for real-time and large-scale detection of soil moisture content in arid areas.


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