Dense Plant Cover Research Articles

Farmer managed natural regeneration to reconstitute agroforestry parklands in Burkina Faso

Burkina Faso is facing an accelerated degradation of natural resources, exacerbated by natural phenomena and human activities which, coupled with the impact of climate change and poverty, have caused food insecurity in the arid province of Passoré. To address these challenges, farmers have been implementing initiatives rooted in local knowledge and traditional practices. The practice of interest is farmer managed natural regeneration (FMNR), an ancestral agroforestry practice that protects and tends to spontaneous tree growth in agricultural fields. A qualitative study conducted in the province of Passoré revealed farmers’ reasons for adopting FMNR. As a low-cost practice that requires few technical or financial resources, farmers are attracted to its affordability. FMNR also enables farmers to circumvent customary prohibitions regarding tree planting, and navigate land ownership dynamics, as it involves tending to spontaneous growth rather than deliberate planting. Since FMNR does not involve tree planting, it does not imply land ownership claims, making it inclusive for migrants and women who have limited land rights. By introducing indigenous species such as Piliostigma reticulatum (bangandé) FMNR helps meet energy needs called for by women, and improves the density of plant cover, restoring clearings while improving livelihoods. FMNR has been instrumental in empowering women by providing commercial opportunities in the non-timber forest product (NTFP) sector, enabling them to earn an independent income, strengthening their autonomy within the household. FMNR has thus become integral to farming systems in Passoré due to its many tangible agronomic, environmental and socioeconomic benefits, offering solutions to land degradation, exclusion from tree planting projects, food insecurity and gender inequality. Broader dissemination of its potential for rapid restoration of forest resources at low cost is, therefore, recommended to help other regions of Burkina Faso overcome their challenges of degradation and climate change.

Hydrogeomorphological processes and plant invasion. What interactions in the case of Asian knotweeds along the Herault River (France)?

AbstractConsidered one of the five major threats to biodiversity worldwide, Invasive Alien Species (IAS) particularly threaten riparian ecosystems. Among the IAS found on riverbanks, Asian knotweeds (Reynoutria spp. including R. japonica Houtt.; R. sachalinensis [F.Schmidt] Nakai and the hybrid R. x bohemica Chrtek & Chrtkova) can barely be controlled as, once established, they disperse easily along stream banks via rhizome or stem fragments transported by water. However, the hydrogeomorphological processes underlying the establishment of Asian knotweeds are poorly understood. The objective of this study was to describe and model the hydrogeomorphological preferences of Asian knotweeds along a Mediterranean river. Based on exhaustive presence/absence surveys, we implemented two models related to the presence of Asian knotweeds: (1) at the river reach scale and (2) at the finer scale of the alluvial bar. Areas of low curvature identified as convex banks and the central parts of alluvial bars appear to be more susceptible to knotweed establishment. Highly disturbed areas were less favorable to maintaining plant species, including Asian knotweeds, while less disturbed areas with denser plant cover were more favorable to Asian knotweeds. The results seem to indicate a trade‐off hypothesis in the knotweed establishment strategy between hydrogeomorphological constraints and strong interspecific competition. Analyzed in the light of the current literature, our final models are designed to integrate hydrogeomorphological processes in order to provide an operational tool to help river managers locate the areas most susceptible to knotweed invasion and with important implications for managing these species in riparian ecosystems.

Proglacial slopes are protected against erosion by trait diverse and dense plant communities associated with specific microbial communities

Soil erosion is a severe threat for ecosystems and anthropogenic infrastructure. Glaciers are retreating rapidly due to global warming and the receding ice leaves unvegetated depositions of sediment, which are prone to mobilisation during precipitation events. Vegetation is known to serve as erosion protection, but how above- and belowground plant traits, vegetation cover and plant diversity on community level are jointly affecting erosion is unclear. Additionally, soil microbial communities may have effects on slope stability by promoting plant growth and function. We measured sediment transport on 30 plots of 2 × 3 m size on proglacial slopes of the Gepatschferner glacier (Kaunertal, Austria) over three years in a natural pristine high alpine environment. Vegetation cover, species abundances and relevant above- and belowground traits were measured for each occurring plant species on community level. Path model analysis revealed that dense and species-rich plant cover characterized by specific plant growth strategies and trait diversity was best suited to decrease erosion. Vegetation properties were also closely linked to the composition of soil microbial communities characterised by next generation amplicon sequencing, which may facilitate soil formation and further enhance the plants’ soil stabilising potential. Our study illustrates that erosion control may benefit from a high vegetation cover, which is facilitated by diverse plant communities with complementary morphological traits. These vegetation properties also affect soil microbiota, but their impact on slope protection in combination with the vegetation remains to be elucidated. Our findings may inform nature-based solutions against erosion such as revegetation of alpine slopes using specific seed mixtures.

Chemotypes of Species of the Genus Thymus L. in Carpathians Region of Ukraine—Their Essential Oil Qualitative and Quantitative Characteristics and Antimicrobial Activity

The study of the R&D in this paper is to determine the range of essential oils (EOs) in the raw materials of species of the genus Thymus of the natural flora in the Carpathian region and their antimicrobial activity. It was found that the component range of EO in species of the genus Thymus depends on the microclimatic conditions of the population. The range of essential oils in the raw material of Th. Serpyllum and Th. Pulegoides is 7–9 mL and Th. Marschallianus is 3.5 mL. The research found that the plants Th. Serpyllum and Th. Pulegoides that grow in sunny habitats have an aromatic mono- and bicyclic monoterpenoid chemotype (K/α-T-neol/ G/p-C/B), with total dominance of carvacrol and p-cymene. The populations of Th. Serpyllum, which grow on the edges of sparse pine forests, and populations of Th. Pullegioide, with denser plant cover and which grow in meadows, have an acyclic and bicyclic monoterpene chemotype (G/α-T-neol/B/K). Plants that grow in the communities of meadow-steppe vegetation have the following chemotypes: Th. Serpyllum—L/K/G with 63% of linalool, Th. Pullegioides—G/α-T-neol/L/B, and Th. Marschallianus—α-T-neol/K/L/α-T-nen/G/B. Of these, the dominant chemotypes are α-terpineol and carvacrol (28:6.5%). A wide spectrum of antimicrobial activity was registered in samples of Th. Pullegoides and Th. Serpyllum that have an aromatic-monoterpenoid chemotype. Essential oils of Th. Pullegoides were dominated by carvacrol, and p-cymene had the highest fungicidal action (41.00 ± 1.0%). Plant populations of Th. Pullegoides and Th. Serpyllum with the aromatic-monoterpenoid chemotype are suggested by R&D to be of use in the pharmaceutical industry. They have high contents of natural components, which are effective in a wide spectrum of antimicrobial activity. The EO of Th. Marschallianus had the lowest influence on the inhibition of bacterial and fungal reproduction.

ОЦЕНКА ЕСТЕСТВЕННЫХ ЛУГОПАСТБИЩНЫХ УГОДИЙ, ОПРЕДЕЛЯЕМЫХ С ПОМОЩЬЮ ДИСТАНЦИОННОГО ЗОНДИРОВАНИЯ И ПРИМЕНЕНИЯ ГИС В ВЫСОКОГОРНЫХ РАЙОНАХ ВОСТОЧНОЙ ТУРЦИИ

The aim of this study was to assess the natural grassland regions for livestock production in the highlands of Eastern Turkey by utilizing Remote Sensing (RS) techniques and Geographic Information Systems (GIS) applications. It was concluded that the natural grasslands make up 2/3 of the whole study area in Kars province. However, in terms of plant cover density this only accounts for 1/3rd of the entire area. In other words, just 181 275.7 hectares out of a total of 638 393.5 hectares of grassland are in a better state for cattle grazing. Finally, digital maps of the greatest quality grasslands were produced.

Late Pleistocene Boulaaba travertine and calcareous tufa, Kasserine, Central Tunisia: Implications for North African spring-fed Ca-carbonates

Late Pleistocene (≈21000 BP) travertine and calcareous tufa deposits have been recognized in the region of Boulaaba, Kasserine in Central Tunisia with a variety of morphological aspects and depositional facies. Morphological aspects of these deposits consist of two elongated continental Ca-carbonate masses defined as fissure-ridges built-up around old fissure networks. Distinction between travertine and tufa lithofacies, based on textural, compositional and topographic settings regarding the entire carbonate masses, have led for travertine to 5 lithofacies: (1) banded travertine fissure infill, (2) bacterial shrubs, (3) stromatolitic laminae, (4) pisoids and (5) speleothem-like travertine growth habits. Tufa is composed of autochtonous tufa lithofacies with (1) phytoherme framestone tufa, (2) calcified insect larval constructions, and clastic alllochtonous tufa lithofacies with (1) matrix-supported microdetrital tufa and (2) grain-supported macrodetrital phytoclast tufa. Both lithofacies show variable diagenetic evolutions with an overall lithification. These deposits are concentrated along the Foussana trough-related normal faults and fractures that belong to the extensional regime of the major strike slip fault of Kasserine that enhanced and facilitated fluid upwelling along with movements of faults which damage and fracture the rocks and increase the overall permeability. During this phase (Late Pleistocene), the deposition of Boulaaba travertine and tufa has implied some paleo-hydroclimatic conditions marked in most North African travertine and tufa depositing sites by (1) a higher water table with abundant effective rainfall on the recharge areas, (2) dense plant cover and soils giving acidic water infiltrations, (3) karstic dissolution of Cretaceous limestones (especially the limestone aquifers of Bireno and Abiod), and (4) a strong water mineralization of the groundwater.

Automatic Detection of Olive Tree Canopies for Groves with Thick Plant Cover on the Ground.

Marking the tree canopies is an unavoidable step in any study working with high-resolution aerial images taken by a UAV in any fruit tree crop, such as olive trees, as the extraction of pixel features from these canopies is the first step to build the models whose predictions are compared with the ground truth obtained by measurements made with other types of sensors. Marking these canopies manually is an arduous and tedious process that is replaced by automatic methods that rarely work well for groves with a thick plant cover on the ground. This paper develops a standard method for the detection of olive tree canopies from high-resolution aerial images taken by a multispectral camera, regardless of the plant cover density between canopies. The method is based on the relative spatial information between canopies.The planting pattern used by the grower is computed and extrapolated using Delaunay triangulation in order to fuse this knowledge with that previously obtained from spectral information. It is shown that the minimisation of a certain function provides an optimal fit of the parameters that define the marking of the trees, yielding promising results of 77.5% recall and 70.9% precision.

Soil organic carbon stocks in mountain periglacial areas of northern Patagonia (Argentina)

ABSTRACT This study presents a detailed soil organic carbon (SOC) inventory for two areas in the mountain periglacial zone of northern Patagonia (altitude range c. 1,400–2,100 m). We describe plant cover and soil profiles at twenty-seven sites representing the main land cover classes and landform types at and above the treeline. The mean SOC 0–100 cm storage is 2.31 kg C m−2 for the combined study areas, which includes 69 percent of bare ground surfaces with negligible SOC stocks. If we consider the vegetated alpine belt only, mean SOC 0–100 cm storage increases to 6.96 kg C m−2. Solifluction has resulted in areas with dense plant cover and deep soil profiles with mean SOC 0–100 cm of 17.1 to 18.3 kg C m−2 and a maximum total stock of 51.5 kg C m−2. Lowest SOC storages of 0.13 to 0.63 kg C m−2 are found in bare and sparsely vegetated high-elevation areas with shallow and stony soils developed in patterned ground (stripes and sorted circles). Projected future increases in ambient temperature will likely result in an upward shift of the alpine vegetation belt with soil development, creating new areas of ecosystem carbon storage.

Invasion and Dispersion of the Exotic Species Procambarus clarkii (Decapoda Cambaridae) in Yeongsan River Basin, South Korea.

Simple SummaryCurrently, the dispersion of the exotic species Procambarus clarkii in the Yeongsan River basin is a major issue in South Korea, where the majority of domestic crayfish occur in upstream river sections, while P. clarkii is mainly abundant in the middle and lower river reaches. In 2018, the species was initially observed only in the Jiseok Stream, a tributary stream of the Yeongsan River. Since then, the species has gradually dispersed in the Yeongsan River basin, and by 2021, the species was recorded in most of the main basin and tributary streams. The larvae of P. clarkii were abundant in areas with dense aquatic plants, whereas adults inhabited areas with silt/clay cover. However, P. clarkii appears to cause little impact on the freshwater ecosystem, despite its extensive dispersion. The species did not utilize native biological communities as food sources and is unlikely to be consumed by predators.The introduction of exotic species negatively affects the distribution and interactions within local biological communities in an ecosystem and can threaten ecosystem health. This study aimed to provide the basic data required to manage P. clarkii in the Yeongsan River basin. We identified the dispersion pattern and evaluated the ecosystem risk of this newly introduced species. The distribution survey investigated Procambarus clarkii populations at 25 sites in the Yeongsan River basin over a four-year period. The initial introduction occurred in Jiseok Stream. The larvae of P. clarkii were most abundant in areas with a dense aquatic plant cover, whereas adults preferred silt/clay areas. The alterations in the water flow by the river refurbishment project (carried out in 2012) increased their preferred habitats and contributed to P. clarkii dispersion. However, stable isotope analysis showed that the dispersion has had little effect on the freshwater ecosystem. The interrelationship between P. clarkii (i.e., larvae and adults) and other biological communities has been limited. Although the rapid dispersion by P. clarkii in the Yeongsan River basin has not impacted the freshwater ecosystem, further ecological information is required on how to manage P. clarkii beyond this early stage of invasion.

The role of plants and soil properties in the enzyme activities of substrates on hard coal mine spoil heaps

Knowledge about biotic (plant species diversity, biomass) and/or abiotic (physicochemical substrate parameters) factors that determine enzyme activity and functional diversity of the substrate on hard coal spoil heaps is limited. Spontaneously developed vegetation patches dominated by herbaceous species commonly occurring on these spoil heaps: grasses (Poa compressa, Calamagrostis epigejos) and forbs (Daucus carota, Tussilago farfara), were examined. The activity of dehydrogenase and alkaline phosphatase was twice as high in plots dominated by grass species compared with those dominated by forbs. Significant positive correlations were found between the activity of dehydrogenase and alkaline phosphatase with pH, available P, soil moisture, and water holding capacity and negative correlations between the activity of urease and soil organic carbon. Strong positive correlations were found between values for Shannon–Wiener diversity index, evenness, species richness and soil functional diversity in plots dominated by grasses. We found that the soil physicochemical parameters had a greater impact on enzyme activity of the substrate than plant biomass and species diversity. However, grasses, through their extensive root system, more effectively increased enzyme activity and health of the substrate than other herbaceous species, and as they stabilize the substrate and form dense plant cover, they can be recommended for reclamation purposes.

Vegetation cover effects on sediment concentration and overland flow under artificial rainfall intensity

Soil erosion depends on a number of factors including rainfall intensity, density of plant cover, and area cover. The objective of this study is to investigate the impact of these factors on flow velocity, overland flow regimes, sediment concentration, and absolute soil detachment. The soil used in this study was sandy remolded agricultural soil. The soil is packed in a tray of 1 m2 fixed on a slope of 3%; five different intensities were simulated under different vegetation cover (density and area). The results indicated that the overland flow velocity with vegetation cover was best described by polynomial function. The mean flow velocity varied from 0.021 to 1.244 m/s. Overland flow regime is subcritical and laminar. However, there are significant relationships between the vegetation cover density and sediment concentration and absolute soil detachment. The sediment concentration ranged from 1.38 to 5.65 kg/m3 whereas the absolute soil detachment ranged from 0.021?10-3 to 1.244?10-3 kg/m2/s. Finally, the vegetation cover presented a good protector to soil sediment from erosion.

EXPERIMENTAL INVESTIGATION OF HYGROTHERMAL BEHAVIOR OF DIRECT GREEN FACADES UNDER SEMI-ARID CLIMATE

This paper aims to investigate the hygrothermal behavior of direct green facades and assess their efficiency under semi-arid climate. For that purpose, a comparative study was conducted in three buildings; two buildings with direct green facades (covered with deciduous climbing plants) and one with a bare facade. Air and surface temperature, relative humidity and wind speed were collected in situ and several factors were taken into consideration as thickness and density of plant cover. The analysis of measurement data revealed that direct green facades contribute to improve the outdoor and indoor thermal environment of buildings due to the effect of shading and evapotranspiration. Moreover, the different types of green facades illustrated their different heat impact on the thermal environment of buildings depending on the density and thickness of the plant layer and the covering ratio.

Effect of no tillage on the physico-chemical properties of soils of the El Koudia region, Rabat (Morocco)

In Morocco, agriculture is an important sector of the economy, accounting for 15 to 20% of Gross Domestic Product. However, it has faced several challenges: intensive tillage of land that has accelerated water erosion, seriously threatening water and soil potential, low plant cover density and misuse of traditional agricultural practices, causing a decrease in organic matter levels and destroying aggregate stability. Climate change is making water and soil management in agriculture more and more complicated. The major challenge for Moroccan agriculture is to increase agricultural production while preserving natural resources. The objective of our study is to evaluate the effect of no tillage (NT) on the physico- chemical properties of soil in the El Koudia experimental station, Rabat, Morocco. The crop is durum wheat, Arrehane variety. Soil samples are pre-dried, ground and screened to 0.2mm for organic matter (OM) analysis and 2mm for the remainder of the analyses. Plugs, canned, are then sintered, screened and dried for structural stability tests. The results show that no tillage (NT) favours the accumulation of surface OM, particularly at the 0-5cm horizon unlike conventional tillage (CT). The NT promotes structural stability, with a mean weight diameter (MWD) = 0.94mm for the NT compared to 0.83mm for the CT. These results show that soils ploughed in CT are more exposed to erosion degradation than soils not ploughed (NT). In addition, NT preserves soil moisture and promotes additional water retention of 5 to 10%.

Classification of The Key Functional Diversity of the Marshes of Southern Iraq Marshes

The term “marshes” refers to the wetlands that are almost of shallow water with relatively dense plant cover, mainly of prominent plants (such as Phragmytes and Typha), or other submerged plants. The marshes of Southern Iraq (Ahwar) are of unique environmental and cultural features that rarely meet in similar habitats worldwide.. They are the most distinctive wetlands in Southwest Asia and worldwide as well. in some times in the past, these wetlands used to cover more than 15,000 km2, however, now it consists of less than this area. Functional diversity is fundamentally considered as a guide to comprehend the nature of ecosystem work. Despite the possession of the marshes of Southern Iraq for many major and minor functions, no study to determine the function diversity of this area was conducted. The present study aims to classify the major functions of the Iraqi marshlands, and then to develop a general framework to determine the extent of the decrease or increase in those functions as a result of the different influences. Also, the current study provides the criteria in preparing estimates for Iraqi marshes rehabilitation programs.

Seasonality, altitude and human activities control soil quality in a national park surrounded by an urban area

Maintaining high soil quality is necessary to let healthy living ecosystems and to protect them from disturbances. The present research aimed to: test the quality of soils located inside the Vesuvius National Park (Southern Italy), an example of a peculiar volcanic system of great naturalistic interest affected by high touristic pressure and human impact, by the analyses of 25 parameters. Other goals of the research were to identify the main drivers among site-specific factors (altitude, seasonality, touristic impact) in defining soil quality and to individuate a Minimum Data Set (MDS) able to assess soil quality inside the Vesuvius National Park. The soil quality index (SQI) was calculated by linear scoring technique applying the “more is better” or “less is better” functions. In order to individuate the MDS, two statistical approaches were performed. In the first approach, not redundant parameters and showing the highest loading values were considered (MDS1); whereas, in the second approach, those with the highest sum of correlation coefficients were considered (MDS2). The SQI, calculated for all the parameters, showed intermediate values (0.44–0.67) reflecting the combination of the good level of naturalness and the metal accumulation. Seasonality affected the soil quality with high value in autumn, when the microclimatic conditions were less suitable for microorganisms and the soil metal contamination degree was lower than in spring. Anyway, also the touristic season inside the National Park affected the qualities of the soils along the two roads as they were similar regardless on accessibility and duration of the traffic flow. Also altitude that, regulating the microclimatic conditions, conditioned the type and density of plant cover affected soil quality. In fact, at low altitude most favourable conditions occurred for soil microbial biomass growth and activities. The MDS1 (C content, total Ni concentration, qCO2 and percentage effect of root elongation for S. saccharatum L.) appeared sufficiently informative to evaluate soil quality.

Sewage sludge as an organic amendment for quarry restoration: Effects on soil and vegetation

AbstractQuarry restoration in Mediterranean environments usually needs organic amendments to improve the substrates used for technosol construction. Digested sewage sludges from municipal wastewater treatment plants are rich in organic matter, N, and P and constitute an available and economically interesting alternative for substrate amendment. However, their pollutant burden and labile organic matter content involve an environmental risk that must be controlled. Moreover, ecological succession in restored areas can be influenced by the use of sludge and should be assessed. To minimize these risks, a new sewage sludge dose criterion relating to its labile organic matter and heavy metal content has been established. Sewage sludge doses currently range between 10 and 50 Mg ha−1. In order to verify the suitability of this dose criterion, 16 areas rehabilitated using sewage sludge located in limestone quarries in a Mediterranean climate in Catalonia (NE Spain) have been assessed. These evaluations focused on physicochemical properties of rehabilitated soils, land degradation processes, and ecological succession. In the short term, 6 months after sludge application, an increment of organic matter content in the restored soils was observed, without significant increases in electrical conductivity or heavy metals content, and with a dense plant cover that contributes to effective soil erosion control. Two years after, ruderal plants were still present but later successional species colonized the restored zones in different degrees. These results suggest that sewage sludge, used as a soil amendment according to the proposed methodology, can safely improve technosol quality without constraints that compromise ecological succession.

Organic matter transformation and porosity development in non-reclaimed mining soils of different ages and vegetation covers: a field study of soils of the zinc and lead ore area in SE Poland

Plant residue decomposition, porosity status and biological activity in heavily polluted with Zn, Pb and Cd post-mining soils were investigated in relation to natural soil in the area. The study was carried out on soils from different ages and vegetation cover. This work aimed at studying the influence of heavy metal concentration on the humus layer formation with the help of micromorphological methods. Soil samples were collected from 5 sites situated in the Zn and Pb mining area and from one site located in the vicinity but unchanged by mining works. In each site, a representative area of about 100 m2 was selected and soil samples from 5 randomly selected plots were taken from surface and subsurface layers. Chemical, micromorphological and biological analyses were conducted in order to evaluate humus transformations occurring in studied soils and to establish the main factors affecting these processes. In images taken from thin sections, we separated and measured areas covered by decomposed organic matter, plant residues and pores. Mine soils had similar pH soil values (6.7–7.1); only one natural soil was moderately acid (pH = 5.6). The soils differed in SOM content, from 30.84 to 168 g kg−1. Mine soils were contaminated with heavy metals up to 10,980 mg Zn, 5436 mg Pb and 95.2 mg Cd·kg−1. The largest amount of the medium-sized and large plant residues (18.4 and 20.5%) were found in post-mining soil covered with xerothermic flora typical of metalliferous areas. The lowest amount of small residues was found in post-mining forest soil. The diversified accumulation of plant residues reflected the organic matter decomposition ratio varying from 1.64 (post-mining soil 15% covered with calamine flora) to 62.7% (natural soil covered with forest). In the natural soil, rounded pores prevailed, while in post-mining soils, planar pores dominated. Invertase activity ranged from 1.64 to 154.2 mg of inverted sugar, and carbon of microbial biomass ranged from 5.94 to 731.2 μg g−1. Both characteristics were related to the amount of organic matter regardless of the heavy-metal pollution. The results showed that a decomposition ratio was lower in mining soils than in the natural soil, and large plant residues were accumulated in surface layers. Microbial activity was more influenced by plant cover density and diversity than by heavy metal concentration. The evolution in the organic matter form and pore shapes with the soil age and the vegetation cover was observed.

Fern cover and the importance of plant traits in reducing erosion on steep soil slopes

Soil slopes constructed in southern China are susceptible to serious erosion due to substrate characteristics and high precipitation, which is commonly mitigated by revegetation. Ferns are potentially useful for erosion control due to their dense plant cover and adaptation to slopes. However, information regarding the effectiveness of ferns in erosion control is scarce. This study assessed the erosion-reducing potential of recently planted ferns on slopes. Five native fern species of southern China, namely, Blechnum orientale, Cyclosorus parasiticus, Dicranopteris pedata, Nephrolepis auriculata and Pteris vittata, were chosen for the assessment. Each fern species was grown to reach two levels of cover (40% and 80%) in 1.0×0.5m2 soil boxes tilted to 50°, and boxes with bare soil acted as the control. The erosion control performance was tested using a rainfall simulator, which provided a rainfall intensity of 100mmh−1 to reflect a heavy rainstorm event. Various plant traits were examined to explore their roles in reducing erosion. The results demonstrated that both cover and plant traits have significant effects on the erosion-reducing potential of ferns. The high cover of ferns (80%) could reduce the runoff volume by 65.0% and sediment loss by 96.1% compared with the control. The leaf area index (LAI), root area ratio (RAR) and root density (RD) were highly correlated with erosion-reducing potential. Among species, N. auriculata outperformed the other species by having stronger performance of these plant traits. To confirm the results further, more field experimentation and comparisons of ferns and grasses in mitigating runoff and sediment loss on soil slopes are necessary to evaluate the effectiveness of ferns in erosion control under in situ conditions.

Environmental Geological Studies on Bicess Island Area, Northwest Libya

Due to the few number of islands encountered in the States of the continent of Africa bordering the Mediterranean Sea, Bicess Island may be considered as one of the most important geological features in Libya. The study represents an attempt to identify the threatening of wild birds on Bicess Island through the studying of the various geomorphologic and structural features as well as the stratigraphic sequence. Bicess Island is located west of the Alkhoms City at the mouth of Wadi Bicess which marks the junction of the Nafusa Mountain base with Mediterranean coast. The genesis of Bicess Island is mostly due to the breaking down caused by wave action with the help of the structural effects in the region. The length of the island reaches 240 m, while the width is varying between 40 m and 160 m. The depth of water at the southern part of Bicess Island reaches about 4 m and varies between 7 m and 12 m at the northwestern part and the northeastern part respectively. Bicess Island posses a rocky beach occupied by algae and characterized by highly steeped and irregular cliffs as well as coasts associated with bays and peaks. The presence of dense plant cover on Bicess Island as well as its separation of being surrounded by sea water caused the human activities to be very limited and the occupation of the island by a great number of wild birds build their nests within the holes existing in rocks belonging to Alkhoms Formation. Caves were found at the base of cliffs. The shape of the caves appears as long cylinders extend along zones of weakness with radius become less to the interior of the rocks. On the roof of the caves there were a lot of joints which became wider forming explosive holes. Land destructions by waves and landslides are the most important factors threatening wild bird lives. In order to protect wild bird populations as well as the unique morphological and geological features, the present study recommends Bicess Island to become a natural reserve.

Using remote sensing data to predict road fill areas and areas affected by fill erosion with planned forest road construction: a case study in Kastamonu Regional Forest Directorate (Turkey).

Forest roads are essential for transport in managed forests, yet road construction causes environmental disturbance, both in the surface area the road covers and in erosion and downslope deposition of road fill material. The factors affecting the deposition distance of eroded road fill are the slope gradient and the density of plant cover. Thus, it is important to take these factors into consideration during road planning to minimize their disturbance. The aim of this study was to use remote sensing and field surveying to predict the locations that would be affected by downslope deposition of eroding road fill and to compile the data into a geographic information system (GIS) database. The construction of 99,500m of forest roads is proposed for the Kastamonu Regional Forest Directorate in Turkey. Using GeoEye satellite images and a digital elevation model (DEM) for the region, the location and extent of downslope deposition of road fill were determined for the roads as planned. It was found that if the proposed roads were constructed by excavators, the fill material would cover 910,621m(2) and the affected surface area would be 1,302,740m(2). Application of the method used here can minimize the adverse effects of forest roads.