scholarly journals Mapping Glitches of Juniper Forests in Lebanon under Natural Conditions and Anthropogenic Activities

2019 ◽  
Vol 09 (02) ◽  
pp. 168-181
Author(s):  
Ihab Jomaa ◽  
Carla Khater
Keyword(s):  
Anthropogenic Activities ◽  
Natural Conditions ◽  
Juniper Forests

scholarly journals The effect of liming on the mineral nutrition of the mountain Norway spruce (Picea abies L.) forest

2009 ◽  
Vol 55 (No. 1) ◽  
pp. 1-8 ◽  
Author(s):  
J. Kulhavý ◽  
I. Marková ◽  
I. Drápelová ◽  
S. Truparová
Keyword(s):  
Norway Spruce ◽  
Mineral Nutrition ◽  
Anthropogenic Activities ◽  
Natural Conditions ◽  
Healthy Development ◽  
Al Content ◽  
The Past ◽  
Spruce Stands ◽  
Calcium Magnesium ◽  
Uptake Of Nutrients

Mineral nutrition represents the uptake, transport, metabolism and utilization of nutrients by the forest stand. These processes influence all physiological functions of trees. A specific minimum amount of all nutrients is necessary for the healthy development and growth of forest trees. The uptake of nutrients is influenced not only by natural conditions but also by anthropogenic activities. During the period of 2000–2005 the mineral nutrition of mountain Norway spruce stands was studied at the study site Bílý Kříž (Moravian-Silesian Beskids Mts., Czech Republic). Research was carried out in a spruce stand that was limed in the past years (in 1983, 1985 and 1987) and in a spruce stand that was not limed in order to compare the liming effect on the mineral nutrition of spruce stands. A positive liming effect was detected in the calcium, magnesium and phosphorus nutrition because their contents in current needles were higher on the limed plots. No liming effect was determined in the nitrogen, potassium and microelement (Fe, Mn, Cu, Zn, Al) content in current needles. Sufficient nutrition of spruce stands only with calcium was recorded on all studied plots.

scholarly journals Germination Capacity of Annona deceptrix (Westra) H. Rainer (Annonaceae) an Endemic and Endangered Species in Manabí, Ecuador

2020 ◽  
Author(s):  
José Pico-Mendoza ◽  
Miryan Pinoargote ◽  
Luis Madrid ◽  
Juan Flor ◽  
Janner Álava ◽  
...  
Keyword(s):  
Endangered Species ◽  
Anthropogenic Activities ◽  
Iucn Red List ◽  
Germination Capacity ◽  
Natural Conditions ◽  
Endangered Tree ◽  
Germination Process ◽  
Endangered Status ◽  
Germination Value ◽  
Direct Sowing

Annona deceptrix is an endemic and endangered tree from Ecuador according to the IUCN Red List of Endangered Species™. Its endangered status has been related with anthropogenic activities and some intrinsic characteristics of this species such as a low germination capacity of its seeds under natural conditions which is a serious limitation to obtain plants to establish conservation and breeding strategies. The objective of this study was to determine the seed germination capacity of A. deceptrix under different conditions and pre-germination treatments as a decisive factor in the survival of the species in ecosystems. The six pre-germination treatments were seed mechanical scarification (fine sandpaper), seed imbibitions in gibberellic acid solutions with three different concentrations (600, 700, 800 ppm) for 24 hours, imbibition of seeds in distilled water for 48 hours and direct sowing (control). For each treatment was sown twenty seeds under greenhouse conditions and germination chamber. The variables evaluated were: total number of germinated seeds, germination capacity, maximum germination value and germination energy. Mechanical scarification was the best treatment with 100 % germinated seed and showed to be significantly different than the other treatment. In this regards, the rest of the treatment the germination ranged between 35 % to 55 % and did not show statistical differences each other. In conclusion, the seeds of A. deceptrix have a low germination capacity in natural conditions and then they need a pre-germination process such as mechanical-scarification to guarantees for their performance in the ecosystems.

scholarly journals The influence of land use on nitrogen and sulfur turnover: a microbial approach

2019 ◽  
Vol 98 ◽  
pp. 06004
Author(s):  
Yolanda Espín ◽  
Guillermo Sanz ◽  
Nicolás Valiente ◽  
Alfonso Menchén ◽  
Beatriz Toledo ◽  
...  
Keyword(s):  
Land Use ◽  
Saline Lake ◽  
Anthropogenic Activities ◽  
Lacustrine Sediments ◽  
Molecular Tools ◽  
Microbial Structure ◽  
Natural Conditions ◽  
Se Spain ◽  
16S Rdna Gene ◽  
Nutrient Turnover

Saline lakes are subject to numerous environmental impacts related to human activities. Pollution is one of the major threats to water bodies, since it produces the increase of nitrogen and sulfur contents, changing the chemical and biological conditions of the ecosystem. Microbially mediated redox processes exert a fundamental control on nutrient and contaminant turnover. Therefore, the aim of this study was to determine the influence of land use on the microbial communities responsible for N and S turnover in the lacustrine sediments from Pétrola Lake (SE Spain) disturbed by anthropogenic activities (agriculture, farming, mining, and wastewaters). To reach this goal, chemical and molecular tools (sequencing of 16S rDNA gene) were applied. The results showed the influence of land use on the chemistry and microbial community structure of the sediments from the saline lake. Compared to natural conditions, wastewater and mining showed the largest differences in terms of microbial structure as a result of salinity. These findings provide better understanding of how land use affects the water chemistry and the abundance of organisms responsible for nutrient turnover.

scholarly journals Reproductive and pollination biology of the Critically Endangered endemic Campanula vardariana in Western Anatolia (Turkey)

2021 ◽  
Vol 154 (1) ◽  
pp. 49-55
Author(s):  
Ümit Subaşı ◽  
Aykut Güvensen
Keyword(s):  
Anthropogenic Activities ◽  
Pollen Viability ◽  
Critically Endangered ◽  
Conservation Strategy ◽  
Western Anatolia ◽  
Natural Conditions ◽  
Single Population ◽  
Stigma Receptivity ◽  
Pollen Presentation ◽  
The Mean

Background and aims – Campanula vardariana (Campanulaceae) is a critically endangered endemic chasmophyte with a single population situated in the west of Turkey. Very little is known about the reproductive biology of C. vardariana and more information is needed to develop a sound conservation strategy for this endemic species.Material and methods – Floral traits such as flower morphology, nectar, and sugar concentration, as well as pollen viability and stigma receptivity were measured in different floral phases. We observed insect visitations to the flowers and identified pollinators. Additionally, we investigated the effect of cross and self-pollination on fruit and seed production.Key results – The flowers of C. vardariana are protandrous. The length of the styles, which were 8.74 mm during the pollen loading phase, reached 11.35 mm during the pollen presentation phase. The visitor observations made on the C. vardariana flowers revealed 11 visitor species from 5 families: 5 Halictidae, 3 Apidae, and one species each from Megachilidae, Colletidae, and Bombyliidae. Lasioglossum spp. touched the anthers and stigma using several parts of their bodies and were significant pollinators of C. vardariana. Under natural conditions, the mean number of seeds per fruit was around 60 after cross pollination, while no fruits were formed when pollinators were excluded.Conclusion – Campanula vardariana is entirely dependent on pollinators for its reproductive success, and bees, especially Halictidae and to a lesser extent Apidae, play an important role. Campanula vardariana is restricted to cracks in calcareous rocks and its population is threatened by goat overgrazing and mining activities (quarry formation). Since seed production is abundant in this population, anthropogenic activities currently form the biggest threat to its existence.

scholarly journals Developmental Dynamics of Localities Severely Affected by Anthropogenic Activities on the Example of Doly Bílina

2009 ◽  
Vol 2 (1) ◽  
pp. 5-19
Author(s):  
Linda Drobilová
Keyword(s):  
Natural Environment ◽  
Anthropogenic Activities ◽  
Mineral Resources ◽  
Original Condition ◽  
Natural Conditions ◽  
Forest Functions ◽  
Long Time ◽  
Landscape System ◽  
Developmental Dynamics

Developmental Dynamics of Localities Severely Affected by Anthropogenic Activities on the Example of Doly Bílina The paper focuses on the area of Doly Bílina in the Most district, on the landscape that has been severely affected by extraction of mineral resources for a long time and represents in terms of natural conditions one of the most damaged regions where no possibility of a return to original condition comes into consideration. By using appropriate remedial and recultivation measures, however, we can create a sort of "alternative" natural environment, which should be able to fulfil a greater part of all wood-producing and beneficial forest functions after a certain time, as did the original landscape system.

Modeling cetacean habitat use in an urban coastal area in southeastern Brazil

2020 ◽  
Vol 642 ◽  
pp. 227-240
Author(s):  
L Lodi ◽  
R Tardin ◽  
G Maricato
Keyword(s):  
Habitat Use ◽  
Protected Areas ◽  
Linear Models ◽  
Anthropogenic Activities ◽  
Buffer Zone ◽  
Humpback Whales ◽  
Southeastern Brazil ◽  
Major Influence ◽  
Cetacean Species ◽  
Few Data

Most studies of cetacean habitat use do not consider the influence of anthropogenic activities. We investigated the influence of environmental and anthropogenic variables on habitat use by humpback Megaptera novaeangliae and Bryde’s whales Balaenoptera brydei off the coast of the Brazilian city of Rio de Janeiro. Although there are 2 marine protected areas (MPAs) in this area, few data are available on cetacean habitat use or on the overlap of different cetacean species within these MPAs. Our aim was to evaluate the effectiveness of the MPAs and propose a buffer zone to better protect the biodiversity of the study area. We conducted systematic surveys and developed spatial eigenvector generalized linear models to characterize habitat use by the species in the study area. Habitat use by humpback whales was influenced only by depth, whereas for Bryde’s whales there was the additional influence of anthropogenic variables. For Bryde’s whales, which use the area for feeding, sea surface temperature and the distance to anchorages had a major influence on habitat use. We also showed that neither of the MPAs in the study area adequately protects the hotspots of either whale species. Most of the humpback whale grid cells with high sighting predictions were located within 2 km of the MPAs, while areas of high sighting prediction of Bryde’s whales were located up to 5 km from the MPAs, closer to beaches. Our findings provide important insights for the delimitation of protected areas and zoning of the MPAs.

Thierry Kuntzel and the Rise of Video Art

2018 ◽  
Author(s):  
Hilary Radner ◽  
Alistair Fox
Keyword(s):  
New Technology ◽  
Video Art ◽  
Video Technology ◽  
Natural Conditions

Raymond Bellour describes how his interest in video art grew out of his personal friendship with Thierry Kuntzel and the latter’s growing interest in experimental filmmaking using the new technology, and how this interest prompted him to seek to understand how the new medium was leading to a modification of perception. He goes on to explain how video technology enables the production of images that escape the natural conditions deemed to constrain photography, also emphasizing the influence of painting on video art.

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