scholarly journals Assessing lake ecological status across a trophic gradient through environmental and biological variables

2019 ◽  
Vol 690 ◽  
pp. 831-840
Author(s):  
Katrina A. Macintosh ◽  
Hannah Cromie ◽  
Elena Forasacco ◽  
Kevin Gallagher ◽  
Fiona L. Kelly ◽  
...  
Keyword(s):  
Ecological Status ◽  
Trophic Gradient ◽  
Biological Variables

scholarly journals Charophyte variation in sensitivity to eutrophication affects their potential for the trophic and ecological status indication

2021 ◽  
pp. 30
Author(s):  
Agnieszka Kolada
Keyword(s):  
Water Quality ◽  
Significant Contribution ◽  
Ecological Status ◽  
Taxonomic Diversity ◽  
Trophic Gradient ◽  
Eutrophic Lakes ◽  
Trophic Conditions ◽  
Index Approach ◽  
The Mean

Charophytes (stoneworts) form a group of macrophytes that are considered sensitive to eutrophication. The high indicator value of charophytes toward eutrophication results in their wide use in the bioassessment systems. I explored the variability of stonewort communities' requirements for trophic conditions in lowland temperate lakes and attempted to determine the role of individual syntaxa in assessing the ecological status of lakes in Poland. The position of charophyte communities' niches along the trophic gradient was analysed using the Outlying Mean Index approach. A few stonewort communities, i.e., Nitelletum opacae, N. mucronatae, N. flexilis and Charetum filiformis appeared to be specialised concerning water quality and may be considered indicators of habitats less eutrophic than the “mean” trophic conditions in the study domain. Most stonewort communities were relatively common in European waters. Four of them, i.e., Charetum tomentosae, C. asperae, C. contrariae and Nitellopsidetum obtusae, can be classified as ‘generalists’ with low marginality and broad ecological tolerance. Most stonewort communities appeared in a broad range of ecological status classes. In the case of 15 communities, 6 to 25% of occurrences were observed in lakes representing a less than good status, and they cannot be considered indicative of good ecological conditions. However, the high taxonomic diversity and extensive phytolittoral zone were most likely to occur when the phytocoenoses of stoneworts were present. In lowland naturally eutrophic lakes inhabited by eurytopic species, the extraordinary role of charophytes in the assessment of the ecological status can be interpreted through their significant contribution to the development of the littoral.

Learned Placebo Effects in the Immune System

2014 ◽  
Vol 222 (3) ◽  
pp. 148-153 ◽  
Author(s):  
Sabine Vits ◽  
Manfred Schedlowski
Keyword(s):  
Nervous System ◽  
Immune System ◽  
Associative Learning ◽  
Placebo Response ◽  
Immunosuppressive Drug ◽  
Immune Functions ◽  
Placebo Effects ◽  
New Therapeutic Approaches ◽  
Biological Variables ◽  
Experimental Approaches

Associative learning processes are one of the major neuropsychological mechanisms steering the placebo response in different physiological systems and end organ functions. Learned placebo effects on immune functions are based on the bidirectional communication between the central nervous system (CNS) and the peripheral immune system. Based on this “hardware,” experimental evidence in animals and humans showed that humoral and cellular immune functions can be affected by behavioral conditioning processes. We will first highlight and summarize data documenting the variety of experimental approaches conditioning protocols employed, affecting different immunological functions by associative learning. Taking a well-established paradigm employing a conditioned taste aversion model in rats with the immunosuppressive drug cyclosporine A (CsA) as an unconditioned stimulus (US) as an example, we will then summarize the efferent and afferent communication pathways as well as central processes activated during a learned immunosuppression. In addition, the potential clinical relevance of learned placebo effects on the outcome of immune-related diseases has been demonstrated in a number of different clinical conditions in rodents. More importantly, the learned immunosuppression is not restricted to experimental animals but can be also induced in humans. These data so far show that (i) behavioral conditioned immunosuppression is not limited to a single event but can be reproduced over time, (ii) immunosuppression cannot be induced by mere expectation, (iii) psychological and biological variables can be identified as predictors for this learned immunosuppression. Together with experimental approaches employing a placebo-controlled dose reduction these data provide a basis for new therapeutic approaches to the treatment of diseases where a suppression of immune functions is required via modulation of nervous system-immune system communication by learned placebo effects.

Partition Coefficient Ratios and Tumour Perfusion Studied with 85mKr and 133Xe

1987 ◽  
Vol 26 (06) ◽  
pp. 253-257
Author(s):  
M. Mäntylä ◽  
J. Perkkiö ◽  
J. Heikkonen
Keyword(s):  
Partition Coefficient ◽  
Partition Coefficients ◽  
Regional Blood Flow ◽  
Blood Perfusion ◽  
Compartmental Analysis ◽  
Malignant Tumour ◽  
Mean Value ◽  
Perfusion Rate ◽  
Biological Variables ◽  
The Mean

The relative partition coefficients of krypton and xenon, and the regional blood flow in 27 superficial malignant tumour nodules in 22 patients with diagnosed tumours were measured using the 85mKr- and 133Xe-clearance method. In order to minimize the effect of biological variables on the measurements the radionuclides were injected simultaneously into the tumour. The distribution of the radiotracers was assumed to be in equilibrium at the beginning of the experiment. The blood perfusion was calculated by fitting a two-exponential function to the measuring points. The mean value of the perfusion rate calculated from the xenon results was 13 ± 10 ml/(100 g-min) [range 3 to 38 ml/(100 g-min)] and from the krypton results 19 ± 11 ml/(100 g-min) [range 5 to 45 ml/(100 g-min)]. These values were obtained, if the partition coefficients are equal to one. The equations obtained by using compartmental analysis were used for the calculation of the relative partition coefficient of krypton and xenon. The partition coefficient of krypton was found to be slightly smaller than that of xenon, which may be due to its smaller molecular weight.

IDENTIFYING THE MOST SUITABLE AREAS FOR SURFACE FLOW WETLAND CONSTRUCTION IN LITHUANIA

2015 ◽  
Author(s):  
Antanas DUMBRAUSKAS ◽  
Nijolė BASTIENĖ ◽  
Petras PUNYS
Keyword(s):  
Constructed Wetlands ◽  
Ecological Status ◽  
Surface Flow ◽  
Gis Analysis ◽  
Proximity Analysis ◽  
Wetland Construction ◽  
The Mean ◽  
Two Phases ◽  
Terrain Features ◽  
Surface Flow Constructed Wetlands

GIS-based approach to find the suitable sites for surface flow constructed wetlands was employed for the Lithuanian river basins with low ecological status. According to the nature of the analysed criteria the flowchart consists of two phases. Criteria used include hydrographical network, soil properties, terrain features, land use, etc. Some of them have strictly defined values (constraints), and other ranges within certain limits (factors). Limited criteria were analysed using rejection principle and influencing factors using proximity analysis and overlay methods. Selecting the potential sites using standard GIS analysis tools there was estimated about 3286 sites for possible wetlands with the mean area of inflow basin about 4 km2 in the basins of water bodies at risk.

PENGARUH KADAR PROTEIN DAN LEMAK PAKAN TERHADAP PERTUMBUHAN DAN KOMPOSISI BADAN IKAN KERAPU MACAN, Epinephelus fuscoguttatus

2016 ◽  
Vol 5 (2) ◽  
pp. 277
Author(s):  
Usman Usman ◽  
Neltje Nobertine Palinggi ◽  
Kamaruddin Kamaruddin ◽  
Makmur Makmur ◽  
Rachmansyah Rachmansyah
Keyword(s):  
Lipid Content ◽  
Lipid Level ◽  
Block Design ◽  
High Growth ◽  
Biological Variables ◽  
Randomized Block Design ◽  
Tiger Grouper ◽  
Test Fish ◽  
Net Cages ◽  
Protein Diets

Penelitian ini dilakukan untuk mendapatkan informasi tentang kebutuhan optimum kadar protein dan lemak pakan terhadap pertumbuhan dan komposisi badan ikan kerapu macan ukuran konsumsi. Sembilan pakan uji dibuat dalam bentuk moist pelet dengan tiga dosis protein (46%, 49%, dan 52%) dan tiga dosis lemak (9%, 11%, dan 13%). Ikan uji dipelihara dalam 27 keramba jaring apung ukuran 1 m x 1 m x 2 m selama 140 hari, diberi pakan uji secara satiasi dua kali sehari dan diset dalam rancangan acak kelompok pola faktorial berdasarkan kelompok ukuran bobot awal ikan yaitu (i) 122,0±4,2 g; (ii) 144,0±7,1 g; dan (iii) 172,9±10,5 g. Hasil penelitian menunjukkan bahwa laju pertumbuhan spesifik dan sintasan ikan relatif sama (>0,05) di antara perlakuan. Efisiensi pakan cenderung meningkat dengan meningkatnya kadar protein dan lemak pakan. Tingkat efisiensi pemanfaatan protein cenderung menurun dengan meningkatnya kadar protein pakan, tetapi meningkat dengan meningkatnya kadar lemak pakan. Hasil analisis proksimat badan ikan menunjukkan bahwa kadar bahan kering dan lemak ikan relatif tidak dipengaruhi (P>0,05) oleh peningkatan kadar protein pakan, namun kadar bahan kering dan lemak ikan tersebut sedikit naik dengan meningkatnya kadar lemak pakan. Kadar protein dan abu ikan relatif tidak dipengaruhi oleh perubahan kadar protein dan lemak pakan. Berdasarkan hasil penelitian ini tampak bahwa pakan dengan kadar protein 49% dan lemak sekitar 11% mampu memberikan pertumbuhan dan komposisi badan ikan kerapu macan yang baik.This experiment was conducted to investigate the optimum dietary protein and lipid level for growth and body composition of tiger grouper. Nine dietary experiments were formulated to moist pellet contain three levels of protein (46%, 49%, and 52%) and three levels of lipid (9%, 11%, and 13%). The fish were fed twice daily to satiation for 140 days in twenty seven net cages of 1 m x 1 m x 2 m, were set up factorial randomized block design based on fish size group i.e. (i) 122.0±4.2 g, (ii) 144.0±7.1 g, and (iii) 172.9±10.5 g. The results shown that specific growth rate and survival rate were not significant different (P>0.05) for all treatments. Feed efficiency increased when protein and lipid content increased. Protein efficiency decreased when protein diets increased and increased when lipid diets increased. No interaction occurred between protein and lipid content to all observable biological variables. Dry matter and lipid content of test fish were not affected by protein diets increase but by lipid diet content. Protein and ash of test fish were not affected by either protein or lipid contained in diet. To assure high growth rates and high quality of fish product, it is suggested to feed tiger grouper with diet containing 49% protein and 11% lipid. 

Rapid Assessment Of Taal Volcano Protected Landscape (TVPL) Terrestrial Biodiversity

2017 ◽  
Vol 11 (1) ◽  
Keyword(s):  
Animal Species ◽  
Rapid Assessment ◽  
Ecological Status ◽  
Taal Volcano ◽  
Ecological Barriers ◽  
Floral Diversity ◽  
Forested Areas ◽  
Baseline Information ◽  
Study Sites ◽  
Terrestrial Biodiversity

With the exponential rise of human activities in the past decades, majority of studies conducted in Taal Volcano Protected Landscape (TVPL) are geared towards the conservation and preservation of Lake Taal’s remaining biodiversity. However, the current structure and assemblage of its terrestrial biotic communities remain relatively unstudied. In this study, we conducted biodiversity censuses in the four sites in TVPL to provide baseline information regarding the community structure of the selected study sites. Comparison of the plant diversity in Taal Volcano Crater Island and Romandan Falls within the forested areas of Mataas na Kahoy, Batangas reveal that both sites support remarkably different vegetation, with the former supporting a smaller floral diversity. The fairly small number of animal samples present difficulty in providing conclusive findings to the wildlife structure of the two study sites. However, the presence of 11 animal species exhibit valuable results in determining the ecological status of TVPL. It is deduced that several ecological barriers exist between the sites, which is attributed to their unique terrestrial biota.

SPATIAL AND SEASONAL ECOLOGICAL STATUS OF FRESH WATER EVALUATED BY MULTIVARIATE ANALYSES

2014 ◽  
Vol 13 (7) ◽  
pp. 1641-1656 ◽  
Author(s):  
Maria-Ema Faciu ◽  
Roxana Nechifor ◽  
Dan Dascalita ◽  
Camelia Ureche ◽  
Dorel Ureche ◽  
...  
Keyword(s):  
Fresh Water ◽  
Multivariate Analyses ◽  
Ecological Status

ECOLOGICAL STATUS AND RECONSTRUCTION OF RYAZAN REGION MELIORATION SYSTEM

1970 ◽  
pp. 33-37
Author(s):  
P. N. Vanyushin ◽  
A. V. Kuzin ◽  
А. А. Pavlov ◽  
А. V. Nefedov ◽  
N. А. Ivannikova
Keyword(s):  
Russian Federation ◽  
Agricultural Land ◽  
Cultural Landscapes ◽  
Land Reclamation ◽  
Ecological Status ◽  
Economic Feasibility ◽  
Drainage Systems ◽  
Viable Systems ◽  
The Russian Federation ◽  
Technical Operation

The article analyzes the current state of the irrigation and drainage systems of the Ryazan region. It is shown that the lack of technical operation of the drainage network led to its failure and failure to perform its functions. Irrigation, in spite of the fact that it gives stability in the years of droughts due to aging and the dismantling of machinery and equipment is not carried out. It is shown that for the reconstruction and / or modernization of irrigation and drainage systems it is necessary on the basis of inventory to determine the environmentally optimal and economically viable systems, their parts and structures that require rehabilitation, reconstruction and / or modernization. The decision to reconstruct may include not only the ameliorative system as a whole, but also some part of it, for example, a canal, pipeline or a separate hydraulic structure, taking into account the justification of economic feasibility. In dry periods, for the Meshcherskaya lowland and areas with peat soils, it is necessary to provide for land-reclamation systems for dual regulation of soil moisture, which reduces the possibility of peat ignition and the spread of fire. It should be borne in mind that the reconstruction of land-reclamation systems has its specific features, which include: socio-economic (increasing the productivity of agricultural land, obtaining additional income, creating modern infrastructure, increasing employment, living conditions, labor, etc.) ; ecological (creation of cultural landscapes, ensuring their ecological sustainability, prevention of land degradation processes, improvement of recreational conditions, elimination of waterlogging, flooding, salinization, erosion, etc.). Reclamation activities are carried out in compliance with the requirements of land, water, forestry legislation of the Russian Federation, as well as the legislation of the Russian Federation on the protection of the environment, on the subsurface, on the plant world and on the animal world.

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