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Abstract

Norway spruce (Picea abies [L.] Karst.) and silver fir (Abies alba Mill.) are main tree species of Central Europe that are currently highly vulnerable in times of global climate change. The research deals with the effect of climate and air pollution on radial growth of silver fir and Norway spruce in mixed age-varied (56 – 146 years) forests in the Jeseníky Protected Landscape Area, the Czech Republic. The objectives were to evaluate biodiversity, structure and production, specifically interaction of radial growth of fir and spruce to air pollution (SO2, NOX, tropospheric ozone) and climatic factors (precipitation, air temperature). Concentration of SO2 and NOX had negative effect on radial growth of fir, while radial growth of spruce was more negatively influenced by tropospheric ozone. Fir showed higher variability in radial growth and was more sensitive to climatic factors compared to spruce. On the other hand, fir was relatively adaptable tree species that regenerated very well when the pressure of stress factors subsided (air pollution load, Caucasian bark beetle, frost damage). Low temperature was a limiting factor of radial growth in the study mountainous area, especially for fir. Fir was significantly sensitive to late frost, respectively, spruce to winter desiccation and spring droughts with synergism of air pollution load. Generally, older forest stands were more negatively influenced by air pollution load and climatic extremes compared to young trees.

Abstract

This study investigated the efficacy of Tamarind Leaves (TL) and Mango Leaves (ML) with Oxytetracycline (OXY) on growth performance, haematoimmunological and disease resistance of Clarias gariepinus juveniles against Aeromonas hydrophila. Experimental diets consist of control (0%), TL2 (1%), TL3 (2%), ML4 (1%), ML5 (2%), OXY6 (30mg/kg diet), (TL+ML) 7, (TL+OXY) 8, (ML+OXY) 9 and (TL+ML+OXY) 10. The fish (3.02±0.01g) were replicated twice with 20 fish per replicate and were fed twice daily at 3% body weight of 40% crude protein for twelve weeks (8 weeks for feeding trial and 4 weeks for challenge test). Mean Weight Gain (MWG), Specific Growth Rate (SGR), Packed Cell Volume (PCV), Haemoglobin (Hb), Lymphocytes (LYM), Globulin (GLO), Amino Alanine Transferase (ALT) and Aspertate Amino Transferase (AST) contents were ascertained using standard technique. The fish were infected with A. hydrophila at 5.94 log10 CFU/ml interperitoneally and fed different diets to evaluate their Relative Percent of Survival (RPS). Data was subjected to descriptive statistics and one-way analysis of variance at P=0.05. Clarias gariepinus juveniles fed treated diets had higher growth rates than the control diet but C. gariepinus fed (TL+ML+OXY) 10 had a significantly higher MWG and SGR of 7.74±0.69 g and 0.97±0.01 g, respectively. The PCV (44.0±2.00%), Hb (14.7±2.00 g/dl), LYM (37.0±2.00), GLO (42.0 ±2.00 g/dl) were higher in the C. gariepinus fed (TL+ML+OXY) 10 than the control diet. The AST and ALT values among the treated groups were lower than the values in the control at the post-challenge test. The RPS against A. hydrophila was higher in the treated groups (100%) than in the control (0%). Fish fed tamarind and mango leaves had enhanced mean weight gain and were more resistant to A. hydrophila infection.

Abstract

Loss of fish biodiversity, especially in the inland and coastal areas, is a major concern in sustainable fish production. Indiscriminate fish catch, climate change and many other anthropogenic activities synergistically affect fish biodiversity. To formulate a sustainable fish biodiversity conservation plan, fish biodiversity in the Andharmanik River, a 40-km-long Hilsa shad sanctuary in the southern part of Bangladesh, was assessed. The study was conducted to understand the status of fish species diversity through sampling in three sampling stations between December 2014 and November 2015. A total of 93 fish species were found belonging to 66 genera, 45 families and 14 orders. Perciformes (27.65%) was found to be the most dominant order, followed by Cypriniformes (20.21%), Siluriformes (21.28%) Clupeiformes (7.45%) Mastacembeliformes (4.26%) and Channiformes (4.26%). Out of the 93 fish species of the river, the percentage compositions of the vulnerable, endangered, critically endangered and not threatened were found to be 14%, 11%, 6% and 59%, respectively. Four population indices viz. Shannon-Wiener’s diversity index (H), Simpson’s dominance index (D), Simpson’s index of diversity (1-D) and Margalef’s index (d) were applied to demonstrate species diversity, richness and evenness of fish species in sampling areas, and the overall values of the indices were 2.70-3.51, 0.10-0.12, 0.88-0.90 and 7.84-8.19, respectively. The main threats to fish biodiversity were reviewed and the measures for fish biodiversity conservation of the river recommended. Indiscriminate fishing using biodiversity destructive gears, as well as losing hydrological and ecological connectivity with the surrounding habitats, were identified as major threats to biodiversity in the Andharmanik River. Effective sanctuary-based co-management, immediate actions for habitat enhancement to conserve and improve fish biodiversity in the river were recommended. Necessary steps to improve hydrological and ecological connectivity for habitat protection and elimination of all destructive fishing gears in order to conserve biodiversity in the Andharmanik River were also suggested.

Abstract

The aim of the research was to verify the functionality of the ecological network elements from the point of view of wildlife mammal migrations in the observed territory. Theoretical basis defines fragmentation of the landscape, the migrations of forest animals, ecological networks, and their connectivity. In the research territory, species such as Capreolus capreolus, Cervus elaphus, Sus scrofa, Vulpes vulpes, Castor fiber and Lepus europaeus were recognized. The result of the issue is the confirmation or reversal of the functionality of the ecological network elements of the forest animal migrations and the actual status in the observed area. In the contact areas of the Small Carpathians forests and the lowland areas, the research was carried out during 2015, 2016, and 2017. The results have shown that the game tends to migrate between the Small Carpathian forests and the adjacent lowland, but the migration potential is very limited because of the presence of strong migration barriers. Biocenters located in the monitored area provide a variety of conditions and are widely used by almost all species, and we consider them to be functional in terms of game migration. Biocorridors are problematic, whose functionality with regard to the migration of wildlife is considerably limited because of the location of the D2 highway and first- and second-class roads.

Abstract

Geospatial technology has an enormous capacity to analyze large and diversified datasets for evaluating the hidden spatial relationship which provides a better comprehension of the subject and helps significantly in policymaking and planning future strategies.

This study has examined the relationship among diversified remote sensing and GIS datasets such as GHG emission from cropland, rice cultivation area, agro-ecological region, Land use/Land cover (LULC) categories, long-term NDVI (1982−2006) based negative changes, agriculture vulnerability, drought-prone area and future (2021, 2050) climate change anomalies (RCP-6) of India for better understanding and knowledge of the GHG emission scenario, vegetation health, LULC, agriculture vulnerability, and future climate change impact. The LULC analysis revealed that 49.6% (1 628 959 km²) of the geographical area was found to be under category ‘cropland’. The 32.5% of the total cropland areas are used for rice cultivation whereas around 76% of this rice cultivation area is producing high GHG emission (>1000 Mg CO2 e/yr.). LULC categories ‘Cropland’ and ‘Plantation’ show the long-term (1982−2006) negative change equivalent to 19.7 and 70.2% respectively. Similarly, around 56% of LULC categories representing the forest show the long-term negative change whereas the maximum change (139 867 km²) was found in the category of ‘Deciduous Broadleaf Forest’. The 30.6% of the LULC category of ‘cropland’ falls in very high agriculture vulnerable areas whereas 31.7% of the same category falls in the drought-prone area. The significant increase in temperature and abrupt rainfall patterns were observed during Kharif and Rabi seasons in the future. Such variation of climate parameter in the future not only adversely affect the agriculture crop production but also the natural vegetation of India.

The outcomes of the present study would support the policymakers of India to implement the climate-smart agriculture (CSA) and REDD+ on an urgent priority based on a proper evaluation of the socio-economic condition of the poor people. It will certainly help in the reduction of GHG emission, forest amelioration, will bring the resilience in livelihood and mitigate the poverty among the rural communities for the betterment of people.

Abstract

The study was conducted in pure Scots pine (Pinus sylvestris L.) forests and mixed forests of Scots pine and silver birch (Betula pendula Roth.) within the Chernihiv Polissya physiographic region of Ukraine. The aim of the study was a comparative analysis of forest mensuration characteristics and health condition of pine and mixed pine-birch stands planted on formerly arable lands and cutover areas after pine stands infected by annosum root rot. It was found that in pine stands planted on formerly arable land, the average diameter of living trees in the root rot disease focus was 1–6% larger and the average diameter of dead trees was 11–23% larger than those outside the disease focus. Due to the pathological loss inside the disease foci, the pine stand density was much lower – by 14–38% and the growing stock volume was 16–35% less as compared to the outside areas. Mixed pine-birch stands (with a predominance of pine trees), established on the cutover areas after pine stands affected by root rot, had a 20% greater stock volume and the birch-pine stands (with birch predominance) in the clear-cuts had 18% greater stock volume than pure pine stands inside the root rot disease area. The pine trees were assessed as “weakened” in the mixed stands and as “severely weakened” in the pure pine stand inside the disease focus. The birch trees in mixed stands were characterized as “healthy”.

Abstract

We studied photosynthetic pigments in needles of Pісеа аbies and P. pungens in plantings exposed to aerotechnogenic influence of various levels in the big industrial center of steppe zone of Ukraine (Kryvyi Rih). We analyzed the pigment content in needles of the second year of life sampled from 30 to 40-year-old trees of both species in 6 monitoring sites for 5 months. For the needles of P. аbies and P. pungens from all the sites, we noticed the decreasing content of chlorophyll a (to 27.2 and 25.0%, respectively) and chlorophyll b (to 17.9 and 20.0%, respectively) from May till September, in comparison with background territory. At the same time, the content of carotenoids performing the protective function in photosynthetic reactions increased up to 26.1 and 24.0%, respectively. For P. аbies and P. pungens growing in conditions of intensive technogenic pressure, we ascertained that, during investigations, the sum of chlorophylls (a + b) rate decreased to 24.4 and 23.6%, respectively; ratio (a/b) decreased to 11.4 and 12.3%, respectively; ratio (chlorophylls [a + b]/carotenoids) also decreased to 30.1 and 38.0%, respectively, in comparison with plants from the least polluted site. It is shown that the most intensive negative influence on plantings is caused by industrial pollution and exhaust gases: the minimum or, more rarely, the maximum rates of pigment content appeared in needles of the plants exactly from these sites. Our research results demonstrate the feasibility of using the pigment complexes of P. аbies and P. pungens, with the assimilative apparatus sensitive to air pollution damage, as indicators of air environmental conditions.

Abstract

The construction of highways leads to several environmental and landscape impacts, including the fragmentation of natural habitats for many animal species. Highway projects are therefore generally accompanied by mobilisations from the inhabitants of the areas concerned and environmental associations. This work aims to model the potential impacts of a highway project in France on ecological networks and to study the reception of the results by the opponents of this project. We have adopted a three-step approach. First, a land-cover map of the study area was produced at a fine scale of 10 m resolution. Second, we developed a multi-species approach by defining fifteen species groups representative of different habitats of our study area. Third, the design of landscape graphs and the resulting calculation of connectivity metrics allowed mapping the impact of the highway on multi-species ecological connectivity. Reflexive feedback from comments on these results by the public during a mobilisation day against the highway project allows assessment of the relevance of such a modelling approach in this context.

Abstract

The aim of this paper is to provide an overview of bluefin tuna, with special regard to its farming challenges. Tuna is one of the most prominent species in fisheries worldwide. The high market value of tuna stocks has led to intensified fishing pressure that resulted in drastic population reductions in every ocean where these fish are found. It is very difficult to obtain the necessary data for the appropriate stock assessment analysis, and there is a very high degree of uncertainty in the models used to evaluate Atlantic bluefin tuna stocks. Tuna-farming could help reduce pressure on the tuna population, but the problem is that the majority of cage-farmed fish is caught in its natural environment (wild population), and thus is fattened or farmed to a certain size. Additionally, the challenges in tuna farming are numerous. Tuna is a fast swimmer, a large energy and oxygen consumer, therefore consuming a large portion of available food to maintain its metabolism. However, due to its delicious taste, high market price and a large demand for this species, pressure will probably continue to grow in the future. Therefore intensive farming, which implies the full breeding cycle in captivity, remains one of the possible solutions that could help reduce the pressure on the tuna population.

Abstract

Providing a live data monitoring of raptor abundances and spatial localization of their most important nesting areas is very helpful in building a strong future study and applying a sound strategy for effective safeguarding of these emblematic species. Using geographic information system (GIS) and global positioning system (GPS) techniques, we investigated spatial patterns of raptors distribution in the northeastern areas of Algeria during two consecutive breeding seasons (2014 and 2015). The total area sampled (31,000 km2) host diverse raptor species (14 species), among them, the threatened species Egyptian vulture (Neophron percnopterus; 108 individuals and 19 active nests) and red-footed falcon (Falco vespertinus; 12individuals). The value of the region is attested by the presence of an abundant population of nesting black kite (Milvus migrans; 337 individuals). The large-scale spatial analyses of the studied region illustrate certain similarities in nesting habitat selection among raptors. Almost all species (90% of 209 nests detected) preferred to nest within multispecies assemblages (20 raptor assemblages found) and occupied altitudinal rocky cliffs across the inland region (semi-arid zones) rather than coastal region (sub-humid zones). Among all raptor species, exclusively, the common kestrel (Falco tinnunculus) is relatively synanthropic, because it was found to breed within cities (tolerate human activities). The raptor community in the coastal versus inland regions differed by 14%. The latter area seems to be more preferred in nest building, probably consequence of their semi-arid bioclimatic and landscapes characteristics, where high elevations and grasslands forming mosaics with Oak, Alpine, and Cedar forests are patchily distributed. The study is a first mapping database of important nesting sites dispatched across the northeastern areas of Algeria, and it can be effectively used in future complementary researches that aim to elucidate environmental factors that affect raptors life cycle.