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Mangrove Vegetation Health Assessment Based on Remote Sensing Indices for Tanjung Piai, Malay Peninsular

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
A more efficient valuation of beaches using tourists’ perspectives and Geographic Information System (GIS): The case of Patenga of Chittagong, Bangladesh

Abstract

The valuation of non–marketed goods and services of beaches in developing nations is rarely conducted; thus, lax management efforts at these resource–rich places often lead to degradation. In an attempt to resolve this issue the research used the travel cost valuation method and incorporated the use of geographic information system to estimate a never-before-done non-market valuation of the area visited by respondents at the beach of Patenga of Chittagong, Bangladesh. The uniqueness of the research stems from defining the area enjoyed by the survey respondents, via mapping, which helped assign the value generated to that particular part of Patenga and not the rest; this significantly decreased the underestimation problem of the travel cost methodology. The research used secondary sources and collected responses and geographical data from surveys conducted over a seven day period in March of 2018, from 277 respondents. A value of at least 14,331,044BDT/USD1.71million was estimated for 2018 for only 9% of Patenga. Furthermore, the Willingness to Pay approach was used to propose an entry fee of 15BDT/USD0.18 which would yield a revenue of more than 6,750,000BDT/USD79,882 around the year. The authors believe, these results will push the policy-makers and encourage stakeholder participation to better implement and monitor environmental management measures at Patenga.

Open access
Morphological characteristics and variation of wood, cone and seed productions in the reforestation of Aleppo pine in Northeastern Tunisia using terrestrial and spatial index approaches

Abstract

For several decades, forest management policies have encouraged land cover changes, with the establishment of tree cover such as Aleppo pine in natural or degraded ecosystems for soil protection and the firewood production. In order to investigate the importance of Aleppo pine trees in the ecosystem, this study was conducted in the reforestation of the Aleppo pine of Northeastern Tunisia. The production of wood, cones and seeds of Aleppo pine in the 6 date reforestation in Northeastern Tunisia were surveyed using 6 plots (20 tree/plot) spread over 6 different location. Our hypothesis was to determine the characteristics that can be decisive in estimating the production of Aleppo pine in reforestation in Tunisia using terrestrial and spatial measurements including (i) age, (ii) dendrometric characteristics, (iii) silvicultural treatments, (iv) stationary data and/ or (v) remote sensing parameter (NDVI: Normalized Difference Vegetation Index). We found that the Aleppo pine in Northeastern Tunisia and at young age trees (14–35 years) were more productive than the regeneration or reforestation stand, either young or old, in Northwest of Tunisia. Wood, cone and seed productions were significantly different amongst the plots (p <0.05). The NDVI was positively correlated with the production of wood, cones and seeds. Stand age, exposure and longitude were also positively correlated with the production. However, longitude and altitude were negatively correlated with the production, showing a negative effect on the morphological traits of trees and, subsequently, their growth. The regression analysis indicates that NDVI and age were the most determinant factors of seed production. This research suggests that reforestation planning, particularly the choice of altitude and latitude, may result in improved tree morphology that may increase Aleppo pine wood seed and cone crops.

Open access
Population changes in former voivodeship cities in Poland in the context of suburbanization processes and loss of the administrative function

Abstract

The article presents an attempt to analyse population changes and to measure the strength of the impact of factors causing these changes in former voivodeship (province) cities in Poland. In view of the ongoing processes of suburbanisation, the discussion also concerns the areas surrounding the city, i.e. those creating urban systems together with the city. These zones were delineated, calling them demographic influence zones, because only demographic factors were involved in defining them. The research was conducted in the period between1999–2015, and took into account the administrative reform of the country that degraded 31 cities from voivodeship (NUTS-2) capitals to poviat (LAU-1) cities. The main aim of the study was to find an answer to the question: do the directions and the strength of population changes confirm a hypothesis of the destructive impact of the loss of administrative function on settlement units. The results of the study only partially confirmed this hypothesis. Although a decrease in the population is overwhelmingly predominant in the city core, in the case of the demographic influence zone, it has already increased. Counting both parts together, it was found that in half of the cases there was a decline and in the other half a growth of the population.

Open access
The Principal Threats to the Standing Water Habitats in the Continental Biogeographical Region of Central Europe

Abstract

This paper discusses threats of standing water habitats of high importance to the European Community in the Continental Biogeographical Region (CBR) of Europe, specifically in Poland, as a reference. The study covers five standing water habitats types distinguished in Natura 2000: 3110, 3130, 3140, 3150, 3160, occurring in 806 Special Areas of Conservation (SACs) in Poland. The most significant threats to standing water habitats in the Continental biogeographical region, result from human-induced changes in hydrological conditions that have modified whole natural systems. Based on multivariate analysis, we found that significant differences in the conservation status of the standing water habitats resulted from a variety of threats, pressures, and activities, among which the most significant are decreased and unstable water resources (3110, 3130, 3140, 3150, 3160), fishing and harvesting aquatic resources (3110, 3130, 3140, 3150, 3160), pollution from use of the catchment (3130, 3140, 3150), improper management and use of the agricultural catchment (3110, 3130, 3140, 3150, 3160) and forest catchment (3110, 3140, 3160), urbanisation, residential and commercial development (3150, 3140), transportation and service corridors (3140> 3160 > 3110, 3150), including parking areas (3140), changes in biocenotic evolution, succession, plant species composition (3110, 3130, 3140, 3150, 3160), succession of invasive species (3130), and more intense touristic exploration (3110, 3130, 3140, 3150, 3160). Only in the case of habitats 3110, 3130, 3140 changes in their conservation status have been associated with climate change.

Open access
The Role of Hillshade, Aspect, and Toposhape in the Woodland Dieback of Arid and Semi-Arid Ecosystems: A Case Study in Zagros Woodlands of Ilam Province, Iran

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
The state of bio-ecological characteristics of the one-year shoots of Robinia pseudoacacia L. Under the conditions of industrial pollution

Abstract

The paper studies the influence of industrial pollution on bio-ecological characteristics of the one-year shoot of Robinia pseudoacacia L. in the conditions of the city of Dnipro, Ukraine. It analyses the state of biometric parameters of the shoot and anatomic indices of the stem of the studied species exposed to toxic gases. It was found that there are adaptive changes in the histological structure of the stem of R. pseudoacacia under the conditions of technogenesis. The study revealed that bio-ecological characteristics of the black locust are highly resistant to industrial emissions with big shares of SO2 and NO2. It was suggested to use R. pseudoacacia for greening of the technogenic territories.

Open access
Trophic characteristics of Lymnaea stagnalis (Mollusca: Gastropoda: Lymnaeidae) in toxic environment

Abstract

The influence of ions of heavy metals (copper, cadmium, nickel, zinc, cobalt and manganese) was investigated on the basis of trophic characteristics: the average daily ration (ADR), and duration of food passage (DFP) of the Lymnaea stagnalis L. in various concentrations of toxicants in vivisection experiment. In addition to these indicators, the total amount of food consumed in the solutions with various concentrations of pollutants was found out during the chronic experiment and it was calculated for an individual (average monthly ration – AMR). It leads to the conclusions about the intensity of food consuming considering different levels of intoxication. In solutions with lethal concentrations, the death of animals occurs during the first day of its impact due to the damage of tissues and organ systems. Chronic lethal concentrations of toxicants inhibit the nutrition of pond snails dramatically. At the beginning of the experiment, solutions of heavy metals with sublethal concentrations give some stimulatory effect on the digestive system of molluscs that is replaced by its suppression in case of longer being in the toxic environment. The influence of toxicants within a subthreshold limit cannot be considered safe because of the cumulative properties of heavy metals – they become sublethal with prolonged exposure time.

Open access
Utricularia vulgaris L. and Salvinia natans (L.) All. heavy metal (Fe, Mn, Cu, Zn and Pb) bioaccumulation specificity in the area of Bardača fishpond

Abstract

Paper deals with seasonal changes in heavy metal bioaccumulation (Fe, Mn, Cu, Zn and Pb) in Utricularia vulgaris L. and Salvinia natans (L.) All. of two localities (Necik and Sinjak – active fishpond basins) in the area of Bardača fishpond. According to our results, the better accumulator of Fe (3035 mg/kg) and Zn was S. natans (163.55 mg/kg), whereas Utricularia vulgaris better accumulates Mn (620 mg/kg) and Cu (10.18 mg/kg). Amounts of Pb in both investigated macrophyte were below the detection level (<0.51 mg/kg). The values of the bioaccumulation factor (BAC) of the tested metals were >1 or ~1 for both species, and the BAC values decreased in the following order in both investigated species: Fe > Mn > Cu > Zn. The results obtained indicated that tested macrophyte show very good characteristics as bioaccumulators and, thanks to this fact, they could be used in phytoremediation technique successfully in water-polluted ecosystem.

Open access
Young urban trees as important structures in the cultural heritage of cities – a case study from Prague

Abstract

Urban trees generate numerous ecosystem services, and these are often closely associated with the species, age and size of trees as well as with their vitality. Generally, the focus of urban and regional planning is aimed at very large trees, because very large trees are considered to be key green structures in an urban green infrastructure. However, there is a significant knowledge gap related to the importance of young trees in cities, despite their value in urban green spaces, greenways, parks, gardens, urban forests, and as components of green roofs and green walls. This study is the result of field mapping young trees in the urban area of the famous European historical city of Prague. Field mapping revealed a total of 40 individual young trees, or young tree groups, with cultural value in the study area of Prague. The results of this empirical study indicate that young trees (not just very large and old trees) can be very important structures for the provision of cultural ecosystem services in cities, and that they can be viewed as living cultural symbols. This is a new aspect in the awareness of the environmental and social roles of urban trees. This case study from Prague suggests that (i) young trees in urban areas need more attention from researchers and (ii) should be incorporated into urban planning as an important component of urban green infrastructure.

Open access