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Ali Najafifar, Jaafar Hosseinzadeh and Abdolali Karamshahi

Abstract

Soil moisture plays a key role in the ecological capability of arid and semi-arid woodland. Reducing soil moisture due to frequent droughts causes pest prevalence and disease outbreak and the consequence of forest dieback. On the other hand, soil moisture is strongly correlated with the amount of radiation received on the Earth's surface. The sun's radiation is traditionally described often by aspect and sometimes by toposhape. The use of the hillshade map for estimating solar radiation is possible through developing GIS. The present study aimed to compare the relationship and the ability of these indices to describe the phenomenon of arid and semi-arid woodland decline better and more accurately in a case study in the west of Iran. To this aim, the aspect and toposhape layers were generated in 5 and 12 classes, respectively. Then, the hillshade map in range of 0-255 was made during the peak of summer heat. The comparison of the dieback ratio in the three characteristic histograms showed that the shade index, unlike the other two indicators, had a significant effect on forest drought (R2=0.91 for linear equation and R2=0.94 for quadratic equation). The results indicated that the application of hillshade in describing and analysing ecological processes by relying on soil moisture such as woodland dieback is superior to the other two indicators. It is suggested that this index be used to obtain a risk model to predict woodlands dieback which are under the pressure of frequent droughts due to climate change or other mortal factors.

Open access

Sheriza Mohd Razali, Ahmad Ainuddin Nuruddin and Marryanna Lion

Abstract

Mangroves critically require conservation activity due to human encroachment and environmental unsustainability. The forests must be conserving through monitoring activities with an application of remote sensing satellites. Recent high-resolution multispectral satellite was used to produce Normalized Difference Vegetation Index (NDVI) and Tasselled Cap transformation (TC) indices mapping for the area. Satellite Pour l’Observation de la Terre (SPOT) SPOT-6 was employed for ground truthing. The area was only a part of mangrove forest area of Tanjung Piai which estimated about 106 ha. Although, the relationship between the spectral indices and dendrometry parameters was weak, we found a very significant between NDVI (mean) and stem density (y=10.529x + 12.773) with R2=0.1579. The sites with NDVI calculated varied from 0.10 to 0.26 (P1 and P2), under the environmental stress due to sand deposition found was regard as unhealthy vegetation areas. Whereas, site P5 with NDVI (mean) 0.67 is due to far distance from risk wave’s zone, therefore having young/growing trees with large lush green cover was regard as healthy vegetation area. High greenness indicated in TC means, the bands respond to a combination of high absorption of chlorophyll in the visible bands and the high reflectance of leaf structures in the near-infrared band, which is characteristic of healthy green vegetation. Overall, our study showed our tested WV-2 image combined with ground data provided valuable information of mangrove health assessment for Tanjung Piai, Johor, Malay Peninsula.

Open access

Woon Hang Lee, Saiful Arif Abdullah and Shukor Bin Md Nor

Abstract

Unabated land use changes in developing countries have imperilled the urban ecosystem resilience. An urban protected area is one of the critical systems to absorb disturbance regimes in the metropolitan area, but it is increasingly pressured by urbanization. Therefore, assessing their land use and landscape pattern changes are pivotal to identify the conservation capacity. We developed land use maps for Klang Gate, Bukit Kutu, and Sungai Dusun wildlife reserves to assess their spatial and temporal land use changes between 1988 and 2012. The degree of fragmentation, the intensity of human impact and structural connectedness for these wildlife reserves were also quantified. The findings revealed that Klang Gate which located adjacent to the highly urbanizing area experienced a very significant loss of forest while built-up area and commercial agriculture gradually encroached into the reserve. It also has a higher degree of fragmentation and human impact than the other two reserves. Human impact inside of Klang Gate was concomitant to the outside. However, Bukit Kutu almost undisturbed and Sungai Dusun was slightly intruded by commercial agriculture. The results help different stakeholders, such as managing authorities and policy planners to strategize new land use planning that utilize limited land-based resources for future economic and social development. As the findings showed that urban protected areas alone are not sufficient in maintaining the urban ecosystem; therefore new conservation planning that integrates other urban green spaces at their surrounding is critical to ameliorating the conservation on a long-term basis.

Open access

Praveen Kumar Rai, Prafull Singh, Varun Narayan Mishra, Anisha Singh, Bhartendu Sajan and Arjun Pratap Shahi

Abstract

An assessment of Varuna river basin of India was performed to study the various drainage parameters in GIS platform. The delineation of drainage network is possible either physically from topographic sheets or with the help data of Digital Elevation Model (DEM) by methods for calculation techniques. Extraction of the basin and sub-basins, stream network has been produced to evaluate the drainage characteristics in the study zone. The entire Varuna river basin has been subdivided into 3 sub-watersheds and 41 morphometric parameters have been computed under four broad categories i.e. drainage network, basin geometry, drainage texture, and relief characteristics. The morphometric analysis has been performed and different parameters have been correlated with each other to understand their underlying connection and their role over the basin hydro geomorphology. The study discloses different types of morphometric analysis and how they influence the soil and topography of the basin. The investigation and estimation of basin morphometry and relief parameters in GIS will be of massive utility in catchment area advancement, understanding the watershed for natural resource evaluation, planning and administration at any scale. The outcomes thus generated equip us with significant knowledge and may also provide an input that are essential in decision making for watershed planning and drainage development of the watershed.

Open access

Katarína Demková, Martin Hais and Magda Edwards-Jonášová

Abstract

Landscape structure is determined by human activities and natural processes. Despite both influences are described in many studies, there remains still question, how the landscape structure reflects the individual socio-economic predictors. To answer this question we compared landscape structure, with emphasis on non-forest woody vegetation, of two states, however, with common socio-economic and political history. Non-forest woody vegetation represents characteristic feature in rural landscape, which increases water retention, biodiversity and bio-migration using green structures. In our study we supposed, that non-forest woody vegetation will have high sensitivity to societal changes and nature conservation measures. On an example of border region in former Czechoslovakia we compared three classes of non-forest woody vegetation (solitaires, patches and linear elements) in three time horizons (1950, 1986, 2011). The most significant differences in spatial structure of non-forest woody vegetation between countries were in the number and area of solitaires, which decreased during the entire period. However, the largest solitaire decrease was in 1950-1986, mainly in correspondence with socialist collective farming. Moreover, the decrease was higher in the Slovak part compared to the Czech part. The primary reason for this was the removal of non-forest woody vegetation on one side and the joining crowns into bigger patches on the other side. The current trend of increasing area of patch and linear elements is related to natural succession. We assume that the main drivers of different development in non-forest woody vegetation in the border region after the split of Czechoslovakia were different management measures applied in nature and landscape conservation and social development.

Open access

S. Robbert Gradstein and Anna Luiza Ilkiu-Borges

Abstract

We describe the new liverwort species Lejeunea ryszardii from montane rainforest in the Central Cordillera of Colombia (Dept. Quindío) and Rectolejeunea halinae from submontane rainforest in the Western Cordillera (Dept. Risaralda). Both species stand out by copious vegetative reproduction via caducous leaves. Lejeunea ryszardii resembles the Caribbean L. paucidentata in the leaf lobes with toothed margins and a narrow base but strikingly differs from the latter species in: 1) leaf margins with mamillose cells, which are sometimes crowned by a small papilla, and with scattered rhizoids with or without a tooth-like base; 2) lobules with narrowly elongate, curved, sharp tooth; 3) stem epidermis brownish and somewhat thick-walled; 4) copious production of caducous leaf lobes. Moreover, L. ryszardii is dark green to brown in color and probably dioicous while L. paucidentata is light green and autoicous. Rectolejeunea halinae resembles the neotropical R. flagelliformis in having ciliate caducous leaves but clearly differs from the latter in the pointed leaf tips, the presence of ocelli in underleaves, and the flagelliform shoots with flat, entire-margined underleaves. The discovery of these new species adds two further endemic taxa to the rich bryophyte flora of the Colombian Andes.

Open access

Paulo E.A.S. Câmara, Jacques van Rooy, Micheline Carvalho Silva and Robert E. Magill

Abstract

In the Flora of southern Africa area, comprising the countries of South Africa, Namibia, Botswana, Lesotho and Swaziland, the moss family Sematophyllaceae consists of three genera (Trichosteleum, Donnellia and Sematophyllum) and nine species. Core sematophyllous taxa with collenchymatous exothecial cells, long rostrate operculum, linear leaf cells and differentiated alar cells are included in the family. Meiothecium fuscescens is transferred to Donnellia and a new combination made. Sematophyllum wageri is reduced to synonymy under S. brachycarpum and a lectotype is designated for S. dregei. Each species is described and its distribution mapped.

Open access

Bruce Allen and William R. Buck

Abstract

The paraleucobryoid Campylopus complex consists of a small group of Andean species distinguished by a leaf cross section identical to that of Paraleucobryum. The complex differs from Paraleucobryum only in having cygneous rather than erect setae and capsule stomata absent rather than present. Here we treat four species, only two of which have previously been recognized in Campylopus. They are C. albidovirens Herzog, C. pittieri R.S.Williams, C. densifolius (Thér.) B.H.Allen & W.R.Buck, comb. nov. and C. ochyriorum B.H.Allen & W.R.Buck, sp. nov. A key is given to the four species; the two nomenclatural novelties are described in detail and illustrated.

Open access

Timo Koponen

Abstract

Some early observations seemed to show that, in the Mniaceae, the doubling of the chromo-some set affects a change from dioicous to monoicous condition, larger size of the gametophyte including larger leaf cell size, and to a wider range of the monoicous counterpart. The Mniaceae taxa are divided into four groups based on their sexual condition and morphology. 1. Dioicous – monoicous counterparts which can be distinguished by morphological characters, 2. Dioicous – monoicous taxa which have no morphological, deviating characters, 3. Monoicous species mostly with diploid chromosome number for which no dioicous counterpart is known, and 4. The taxa in Mniaceae with only dioicous plants. Most of the monoicous species of the Mniaceae have wide ranges, but a few of them are endemics in geographically isolated areas. The dioicous species have either a wide holarctic range or a limited range in the forested areas of temperate and meridional North America, Europe and SE Asia, or in subtropical Asia. Some of the monoicous species are evidently autodiploids and a few of them are allopolyploids from cross-sections of two species. Quite recently, several new possible dioicous – monoicous relationships have been discovered.

Open access

Michael S. Ignatov, Elena A. Ignatova, Oxana I. Kuznetsova and Vladimir E. Fedosov

Abstract

The moss family Hylocomiaceae is studied for the generic level taxonomy within a molecular phylogenetic approach. We confirm segregating of the species formerly known as Rhytidiadelphus triquetrus to Hylocomiadelphus Ochyra & Stebel from the genus Rhytidiadelphus. Hylocomiadelphus forms a clade with Loeskeobryum and Meteoriella, sharing with both genera cordate to auriculate leaf bases and non-squarrose leaves, and with the former undulate leaves and reticulate exostome teeth ornamentation. However, Loeskeobryum differs from Hylocomiadelphus in having paraphyllia, while Meteoriella has a straight capsule and reduced peristome, likely caused by its epiphytic ecology. In the group of species closely related to R. squarrosus, in addition to R. subpinnatus, the third species with North Pacific distribution is described as R. pacificum. Macrothamnium is found deeply nested in Rhytidiadelphus, although no nomenclatural implications are suggested at the moment due to insufficient sampling. Hylocomium splendens var. splendens and var. obtusifolium were found intermingled in the phylogenetic tree, indicating no correlation between morphology and variation in ITS region, thus supporting a view that these taxa are merely environmentally induced morphs.