scholarly journals Divergent Adaptation Strategies of Vascular Facultative Epiphytes to Bark and Soil Habitats: Insights from Stoichiometry

Forests ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 16
Author(s):  
Tingting Zhang ◽  
Wenyao Liu ◽  
Tao Hu ◽  
Dandan Tang ◽  
Yuxuan Mo ◽  
...  
Keyword(s):  
Elemental Composition ◽  
Forest Ecosystems ◽  
Adaptation Strategies ◽  
P Elements ◽  
Nutritional Conditions ◽  
Variable Element ◽  
C:P Ratios ◽  
Strong Control ◽  
Forest Habitats ◽  
Cultivation Experiment

Understanding the stoichiometric traits of plants is critical for studying their ecological adaptation strategies. Facultative epiphytes (which can also live on the ground) are an important component of epiphytic flora of montane forest ecosystems. However, a key gap persists in our understanding how facultative epiphytes can adapt different nutritional conditions of ground and canopy habitats? To study adaptive strategies of facultative epiphytes and the characteristics of the content and stoichiometric homeostasis of C, N, and P elements, we conducted a field experiment and a greenhouse N and P additions cultivation experiment. We found that epiphytic individuals of facultative epiphytes showed lower C:N and C:P ratios, higher variation in elemental composition, and more pronounced N limitation than terrestrial individuals. Moreover, facultative epiphytes showed strong control over the elemental composition of leaves, and their stoichiometric homeostasis of leaves and stems were stronger than roots. Furthermore, the homeostasis of facultative epiphytes decreased in the order N > P. Our results indicated that epiphytic and terrestrial individuals of facultative epiphytes have difference in nutrient limitation, and they use plastic strategies in different habitats. Epiphytic individuals survive in the intermittent habitat through luxury consumption of nutrient while terrestrial individuals were relatively conservative nutrient users. Furthermore, our results implied that facultative epiphytes maintain stable metabolic leaf activity via variable element concentrations of roots to adapt to highly heterogeneous forest habitats.

scholarly journals Ecological-phytocenotic analysis of the field layer of urban recreational forests (on the example of Kaluga and Obninsk)

2020 ◽  
pp. 68-75
Author(s):  
A. A. Evseeva
Keyword(s):  
Forest Ecosystems ◽  
Urban Forests ◽  
Practical Significance ◽  
Anthropogenic Pressure ◽  
Forest Communities ◽  
Field Layer ◽  
The Stability ◽  
The City ◽  
Forest Habitats ◽  
Observation Period

The aim of this study is to study the diversity of the ecological-coenotic structure of the field layer of the residual urban forests, using as an example the cities Kaluga and Obninsk, which have different approaches to the conservation of residual forest communities in the city. Obninsk practices the conservation of forest zones that have entered the urban environment as recreational objects, while in Kaluga, such forest communities are in a state of interrupted succession and have experienced forestry activities. The objectives of the study are to study the ecological-coenotic and ecological-biological spectra of the field layer of forest ecosystems, and to identify adventive and protected plant species. The study took place in 2014–2015. In the forest communities under study, 30 sites were selected for geobotanical descriptions by the Braun-Blanquet method at different periods of the growing season (in June and August) to fully cover floristic diversity. A total during the observation period were made 240 floristic descriptions. Kaluga city forests turned out to be more susceptible to negative changes occurring in conditions of recreational for-est management. The field layer of the Kaluga forest recreational zones turned out to be more susceptible to negative changes occurring under the influence of anthropogenic pressure, in comparing with the Obninsk forest recreational zones. This is ex-pressed in the proportion of ecological-coenotic and ecological-biological groups, the presence of a greater number of alien species in the studied communities of Kaluga, which indicates greater resistance to the recreational load of the city forests of Obninsk. For example, the share of the group of forest habitats is much higher in Obninsk, where forest species make up more than half of all types of grass layer (54,2%). In the Kaluga forests, the share of forest habitats is lower and amounted to 47,5%. The discovered difference in the stability of the field layer of the Obninsk forests is presumably due to the strategy of their conservation in the urban area in a state of natural succession. The practical significance of the results obtained can be the possibility of using them to determine the degree of negative changes in recreational forests. The direction of further research can be directed at organizing monitoring of the urban forests of Kaluga and Obninsk according to the state of the field layer

scholarly journals Woodland key habitat contribution to preserve biological diversity in Lithuania: assessing the difference between 2005 and 2017

2021 ◽  
Vol 67 (No. 9) ◽  
pp. 436-448
Author(s):  
Indrė Ruškytė ◽  
Gediminas Brazaitis ◽  
Michael Manton ◽  
Žydrūnas Preikša
Keyword(s):  
Spatial Distribution ◽  
Forest Conservation ◽  
Forest Ecosystems ◽  
Biological Diversity ◽  
Species Assemblages ◽  
Species Occurrence ◽  
Conservation Action ◽  
Conservation Policies ◽  
The Difference ◽  
Forest Habitats

In response to the degradation of forest ecosystems, their habitats and the loss of species, many formal conservation policies and voluntary forest conservation tools have been proposed and implemented. The woodland key habitat (WKH) is one such initiative that aims to protect biodiversity. This generally involves two key actions: (i) the creation of policy (conservation action) and (ii) the consequences of the policy or initiative in the field. However, the final step of measuring their success in the field is often missing. The aim of this study is to assess the contribution of the WKH initiative to conserve biodiversity in Lithuania. We compared the changes in spatial distribution, species assemblages and richness within the WKH network between 2005 and 2017. Results showed that the spatial distribution of WKHs decreased in number and by area after 12 years. However, species occurrence, abundance and richness of the WHK network generally increased. In conclusion, we found the WKH initiative has contributed to the conservation of forest habitats and biodiversity in Lithuania. However, the future of the WKH network is uncertain due to the current voluntary system, lack of support and funding.

scholarly journals Distribution and status of threatened and endemic marsupials on the offshore islands of south-east Sulawesi, Indonesia

2019 ◽  
Vol 41 (1) ◽  
pp. 76 ◽  
Author(s):  
Thomas E. Martin ◽  
Joseph Monkhouse ◽  
Darren P. O'Connell ◽  
Kangkuso Analuddin ◽  
Adi Karya ◽  
...  
Keyword(s):  
Protected Areas ◽  
Forest Ecosystems ◽  
Range Extension ◽  
Short Term ◽  
Disturbed Forest ◽  
Forest Habitats

We highlight hitherto unreported populations of two globally threatened phalangerid species on south-east Sulawesi’s offshore islands – bear cuscus (Ailurops ursinus) and small Sulawesi cuscus (Strigocuscus celebensis) – and observations of a third range-restricted species – Peleng cuscus (Strigocuscus pelengensis). Our data are based on records made during 11 years of seasonal surveys on Buton, and short-term expeditions to Kabaena and Manui. Our observations of S. celebensis on Buton, where it occurs in three protected areas, represent an important range extension for this species, as do our observations of A. ursinus on Kabaena, where it is also widespread. We also report the unexpected presence of S. pelengensis on Manui. Buton, in particular, appears to be an important stronghold for both A. ursinus and S. celebensis, given that forest ecosystems here remain extensive and relatively intact. Both these species may also display a previously unreported adaptability to disturbed forest and even some non-forest habitats within our study area. Hunting pressures, a proven threat to these species in northern Sulawesi, may also be lesser here.

scholarly journals Adaptation Strategies and Approaches for California Forest Ecosystems

2020 ◽  
Author(s):  
Christopher W. Swanston ◽  
Leslie A. Brandt ◽  
Patricia R. Butler-Leopold ◽  
Kimberly R. Hall ◽  
Maria K. Janowiak ◽  
...  
Keyword(s):  
Climate Change ◽  
Forest Ecosystems ◽  
Forest Health ◽  
Adaptation Strategies ◽  
Past Century ◽  
The Past ◽  
Pest Infestation ◽  
Fire Exclusion ◽  
To Come ◽  
Forest Conditions

Forest health has never been a more urgent concern in California. A variety of forest ecosystem types have experienced extraordinary combinations of stressors and disturbances over the past century, which have resulted in significant changes to forest conditions. Current conditions are a product of multiple interacting factors, including fire exclusion, historic logging practices, increased wildland-urban-interface expansion and, more recently, the effects associated with climate change. The intersection of the factors has led to high severity fire, drought linked mortality, and pest infestation and disease in the affected forests. It’s increasingly clear that the expected effects of climate change will further impact California forest ecosystems, potentially compelling and, in some cases, forcing the application of targeted adaptation strategies and approaches in the years and decades to come.

scholarly journals Elemental Composition (C, N, P) and Cell Volume of Exponentially Growing and Nutrient-Limited Bacterioplankton

2002 ◽  
Vol 68 (6) ◽  
pp. 2965-2971 ◽  
Author(s):  
Katarina Vrede ◽  
Mikal Heldal ◽  
Svein Norland ◽  
Gunnar Bratbak
Keyword(s):  
Elemental Composition ◽  
Standard Error ◽  
Stationary Phases ◽  
Growth Conditions ◽  
Elemental Content ◽  
Bacterial Cells ◽  
Batch Cultures ◽  
C Cell ◽  
Average Standard Error ◽  
C:P Ratios

ABSTRACT Marine bacterioplankton were isolated and grown in batch cultures until their growth became limited by organic carbon (C), nitrogen (N), or phosphorus (P). Samples were taken from the cultures at both the exponential and stationary phases. The elemental composition of individual bacterial cells was analyzed by X-ray microanalysis with an electron microscope. The cell size was also measured. The elemental content was highest in exponentially growing cells (149 ± 8 fg of C cell−1, 35 ± 2 fg of N cell−1, and 12 ± 1 fg of P cell−1; average of all isolates ± standard error). The lowest C content was found in C-limited cells (39 ± 3 fg of C cell−1), the lowest N content in C- and P-limited cells (12 ± 1 and 12 ± 2 fg of N cell−1, respectively), and the lowest P content in P-limited cells (2.3 ± 0.6 fg of P cell−1). The atomic C:N ratios varied among treatments between 3.8 ± 0.1 and 9.5 ± 1.0 (average ± standard error), the C:P ratios between 35 ± 2 and 178 ± 28, and the N:P ratios between 6.7 ± 0.3 and 18 ± 3. The carbon-volume ratios showed large variation among isolates due to different types of nutrient limitation (from 51± 4 to 241 ± 38 fg of C μm−1; average of individual isolates and treatments ± standard error). The results show that different growth conditions and differences in the bacterial community may explain some of the variability of previously reported elemental and carbon-volume ratios.

scholarly journals The diet of the roe deer (Capreolus capreolus) in the forest ecosystems of Zhytomirske Polesie of the Ukraine

2015 ◽  
Vol 76 (2) ◽  
pp. 184-190 ◽  
Author(s):  
Volodymyr Krasnov ◽  
Zoia Shelest ◽  
Sergii Boiko ◽  
Igor Gulik ◽  
Waldemar Sieniawski ◽  
...  
Keyword(s):  
Vascular Plants ◽  
Forest Ecosystems ◽  
Roe Deer ◽  
Stomach Contents ◽  
Capreolus Capreolus ◽  
Natural Flora ◽  
Dietary Component ◽  
Main Component ◽  
Forest Plants ◽  
Forest Habitats

Abstract The botanical composition of the European roe deer diet in the radioactively contaminated forest ecosystems of Zhytomirske Polesie of the Ukraine was investigated. Deer were caught monthly over a two–year period on three plots in forest habitats typical for Zhytomirske Polesie (fresh and moist mixed coniferous forests and mixed broadleaved forests). An analysis of the stomach contents of hunted deer showed that they consumed leafy as well as leafless stems, grasses, fruits and mushrooms depending on the season and availability of forest plants. Each season was characterized by one major dietary component. In the spring, the main component of the deer diet was the stems of woody plants. 44 species of vascular plants (3% of the natural flora of the region) were identified in the roe deer diet including 41 species of Magnoliophyta, of which 34 species of Magnoliopsida and 7 species of Liliopsida, 2 species of Polipodiophyta and one species of Pinophyta. Species such as aspen (Populus tremula), oak (Quercus robur), blackberry (Rubus nessensis) and bilberry (Vaccinium myrtillus) were consumed year-round.

Alterations of ultrastructure and elemental composition in cultured human epidermal keratinocytes after treatment with nitrofurazone and silver sulfadiazine

1987 ◽  
Vol 45 ◽  
pp. 676-677
Author(s):  
A. R. Crooker ◽  
M. C. Myers ◽  
T. L. Beard ◽  
E. S. Graham
Keyword(s):  
Electron Microscopy ◽  
Elemental Composition ◽  
Pyrolytic Carbon ◽  
Human Keratinocytes ◽  
Silver Sulfadiazine ◽  
Epidermal Keratinocytes ◽  
Human Epidermal Keratinocytes ◽  
Culture Systems ◽  
Cytotoxicity Endpoints

Cell culture systems have become increasingly popular as a means of screening toxic agents and studying toxic mechanisms of drugs and other chemicals at the cellular and subcellular levels. These in vitro tests can be conducted rapidly in a broad range of relevant mammalian culture systems; a variety of biological and biochemical cytotoxicity endpoints can be examined. The following study utilized human keratinocytes to evaluate the relative cytotoxicities of nitrofurazone (NF) and silver sulfadiazine (SS), the active ingredients of FURACIN(R) Topical Cream and SILVADENE(R) Cream, respectively. These compounds are anti-infectives used in the treatment of burn patients. Cell ultrastructure and elemental composition were utilized as cytotoxicity endpoints.Normal Human Epidermal Keratinocytes (HK) were prepared from the EpiPackTM culture system (Clonetics Corporation, Boulder, CO). For scanning electron microscopy (SEM) and transmission electron microscopy (TEM), cells were seeded on sterile 35 mm Falcon plastic dishes; for elemental microanalysis, cells were plated on polished pyrolytic carbon discs (E. Fullam, Latham, NY) placed in the culture dishes.

Electron probe x-ray microanalysis and electron microscopy of amino acid absorption and transport by the small intestine: inhibition by chemical poisons and correlation to the elemental composition of the epithelial cells

1986 ◽  
Vol 44 ◽  
pp. 134-135
Author(s):  
A. J. Tousimis
Keyword(s):  
Small Intestine ◽  
Amino Acid ◽  
Epithelial Cells ◽  
Elemental Composition ◽  
Isotope Labeling ◽  
Structural Components ◽  
X Ray ◽  
Human Small Intestine ◽  
Transport Studies

The elemental composition of amino acids is similar to that of the major structural components of the epithelial cells of the small intestine and other tissues. Therefore, their subcellular localization and concentration measurements are not possible by x-ray microanalysis. Radioactive isotope labeling: I131-tyrosine, Se75-methionine and S35-methionine have been successfully employed in numerous absorption and transport studies. The latter two have been utilized both in vitro and vivo, with similar results in the hamster and human small intestine. Non-radioactive Selenomethionine, since its absorption/transport behavior is assumed to be the same as that of Se75- methionine and S75-methionine could serve as a compound tracer for this amino acid.

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