The role of plant substrate type in shaping the composition and diversity of epiphytic diatom assemblages in a eutrophic reservoir

2017 ◽  
Vol 189 (2) ◽  
pp. 117-135 ◽  
Author(s):  
Markéta Fránková ◽  
Kateřina Šumberová ◽  
Jan Potužák ◽  
Ondřej Vild
Keyword(s):  
Substrate Type ◽  
Diatom Assemblages ◽  
Eutrophic Reservoir

scholarly journals Diatom Biodiversity in Karst Springs of Mediterranean Geographic Areas with Contrasting Characteristics: Islands vs Mainland

Water ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2602 ◽  
Author(s):  
Giuseppina G. Lai ◽  
Sara Burato ◽  
Bachisio M. Padedda ◽  
Raffaella Zorza ◽  
Elisabetta Pizzul ◽  
...  
Keyword(s):  
Anthropogenic Impact ◽  
Multivariate Analyses ◽  
Winter Season ◽  
Global Scale ◽  
Diatom Assemblages ◽  
Karst Springs ◽  
Karst Ecosystems ◽  
Structural Indices ◽  
Epilithic Diatom

Karst ecosystems are considered as priority environments for the protection of biodiversity on a global scale. This study provides a first comparative analysis of epilithic diatom flora from karst springs in two Mediterranean geographic areas (Spain and Italy) with contrasting characteristics (islands vs mainland). We investigated twenty-three springs with different anthropogenic impact levels once in the winter season between 2007 and 2017 (N = 23). A total of 176 diatom taxa (56 genera) were found of which 101 (44 genera) were observed in single sites. A general good biotic integrity was revealed by structural indices (species richness, diversity and evenness). However, crenophilous species were generally present and abundant in less impacted springs. Comparing islands and mainland, significant differences were found in species composition and diversity (H’) based on multivariate analyses (global R = 0.610; p = 0.001) and t-test (t = 2.304; p = 0.031). Discharge and Cl− were the most significant variables in determining diatom assemblages. Our results confirm the role of springs as multiple ecotones and refuges for rare species and suggest that the geographic insularity may be an important factor in maintaining diatom biodiversity.

scholarly journals The Role of Substrate Type, Moisture and Temperature on the Vertical Growth of Terricolous Lichens

2018 ◽  
Author(s):  
Julián Monge-Nájera
Keyword(s):  
Water Levels ◽  
Soft Ground ◽  
Substrate Type ◽  
Main Determinant ◽  
Vertical Growth ◽  
Terricolous Lichens ◽  
The Caribbean ◽  
Terricolous Lichen ◽  
Recorded Temperature

Lichens are traditionally divided into short “crustose”, intermediate “foliose” and tall “fruticose” types, a practice that hides a growth continuum. Substrate, temperature and water are thought to affect vertical growth, but such factors are difficult to measure, because, for example, the water actually available to lichens does not match rainfall patterns or even ground water levels. To reliably assess the effect of those factors, I recorded temperature, moisture, and substrate in and under individual terricolous lichen colonies in 60 fixed quadrats on April, August, October, and December of 2015 (Cerro de la Muerte, Costa Rica, 9°33′N; 83°45′W). The measurements were taken inside the colonies themselves (rather than on the general environment), covering an annual cycle of the relatively simple páramo habitat, where animals and vegetation have less impact than in lower ecosystems. The hypotheses were that lichens would grow taller on softer, warmer, and moister ground; on the Caribbean versant; and on the rainy season. Results matched the hypotheses, with one exception: lichens on soft ground were not taller than those on rock. Caribbean colonies were, on the average, 7 cm taller than those on the drier Pacific versant. Physiologically available water seems to be the main determinant of lichen vertical growth: more water means taller lichens and greater protection from climatic change for both the lichens and their microcommunities.

scholarly journals KANDUNGAN N DAN P HASIL DEKOMPOSISI SERASAH DAUN MANGROVE PADA SEDIMEN DI MARON MANGROVE EDU PARK, SEMARANG The Content of N and P Results of Decomposition of Litter of Mangrove Leaves in Sediments at Maron Mangrove Edu Park, Semarang

2019 ◽  
Vol 8 (3) ◽  
pp. 226-233
Author(s):  
Hafidha Murti Kanti ◽  
Supriharyono Supriharyono ◽  
Arif Rahman
Keyword(s):  
Leaf Litter ◽  
Total Nitrogen ◽  
Sandy Loam ◽  
Substrate Type ◽  
Observation Station ◽  
Mangrove Species ◽  
Mangrove Ecosystems ◽  
Sediment Types ◽  
Temperature Ranges

ABSTRAK Dekomposisi serasah daun yang disertai pelepasan nutrien merupakan fungsi yang sangat penting di perairan mangrove. Unsur hara yang diperlukan bagi lingkungan dari hasil proses dekomposisi antara lain N (Nitrogen) dan P (Phospor). Maron Mangrove Edupark merupakan salah satu ekosistem mangrove yang terletak di Tugurejo, Kota Semarang. Kawasan ini terdapat tambak dan dekat dengan pantai sehingga berfungsi sebagai pencegah abrasi. Untuk mengetahui peran vegetasi mangrove bagi lingkungan, dilakukan penelitian untuk mengetahui kandungan N dan P hasil dekomposisi serasah daun mangrove pada sedimen. Waktu pelaksanaan penelitian dimulai tanggal 25 Maret 2019 sampai 22 April 2019. Tujuan dari penelitian ini adalah untuk mengetahui mengetahui kerapatan jenis mangrove yang ada, mengetahui kandungan N dan P pada hasil dekomposisi serasah daun mangrove pada sedimen dan hubungannya dengan tipe sedimen di Maron Mangrove Edupark, Semarang. Metode yang digunakan dalam penelitian ini adalah metode eksperimental melalui kontrol, manipulasi perlakuan di lapangan dan obervasi di lapangan. Penentuan stasiun berdasarkan jenis substrat, dan terdapat 4 stasiun penelitian. Hasil dari penelitian ini adalah didapatkan data kerapatan mangrove berkisar 2,72 Ind/m2 sampai 4,20 Ind/m2. Nilai suhu air berkisar 28-30°C, suhu udara berkisar 28-30°C , pH berkisar 6-7, salinitas berkisar 26-29, dan nilai DO berkisar 3,543-5,029. Kandungan nitrogen total berkisar 0,004-0,074% dan phospat berkisar 0,164-1,52%. Tekstur sedimen di stasiun A lempung berpasir, stasiun B lempung liat berpasir, stasiun C dan D substrat liat. Terdapat hubungan korelasi yang tinggi antara tekstur sedimen dengan nitrogen total, dan hubungan korelasi sedang dengan phospat. ABSTRACT Leaf litter decomposition which accompanied with releasing nutrient have an important function in mangrove waters. Nutrients needed for the environment from the results of decomposition, those are N (Nitrogen) and P (Phospor). Maron Mangrove Edupark is one of the mangrove ecosystems located in Tugurejo, Semarang City. This area has a pond and close to the beach so it serve an abrasion deterrent. To determine the role of mangrove vegetation for the environment, a study was conducted to determine the content of N and P resulting from decomposition of mangrove leaf litter in sediments. The study had been carried at from March 25, 2019 to April 22, 2019. The purpose of this study is to determine the density of existing mangrove species, determine the content of N and P in the decomposition of mangrove leaf litter in sediments and their relationship with sediment types at Maron Mangrove Edupark, Semarang. The method is an experimental method through control, manipulation of treatment in the field and observation. Station determination is based on substrate type, and there are 4 stations. The results of this study are the mangrove densities ranging from 2.72 Ind / m2 to 4.20 Ind / m2. The temperature of the water ranges from 28-30°C, the air temperature ranges from 28-30°C, pH ranged from 6-7, salinity ranged from 26-29, and DO values ranged from 3.543-5.029. The total nitrogen content ranges from 0.004-0.074% and phosphate ranges from 0.164 to 1.52%. Sediment texture in station A is a sandy loam, station B is a sandy clay loam, station C and D is a clay. There is a high correlation between the texture of sediment and total nitrogen, and a moderate correlation with phosphate.

Role of hydrological and hydromorphological factors in ecological quality of medium-sized lowland streams

2010 ◽  
Vol 41 (3-4) ◽  
pp. 330-337
Author(s):  
Gunta Springe ◽  
Laura Grinberga ◽  
Agrita Briede
Keyword(s):  
Environmental Factors ◽  
Ecological Quality ◽  
Substrate Type ◽  
Lowland Streams ◽  
Biological Communities ◽  
Biological Quality Elements ◽  
Stream Width ◽  
Stream Depth

The development of biological communities is an important research issue regarding biological quality elements. However, it is still uncertain how different organism groups and their metrics are affected by different environmental factors. A study of high-quality sites of medium-sized lowland streams typical for Latvia (ecoregion Baltic province) was carried out with an emphasis on hydrological and hydromorphological characteristics. The investigations were carried out within the STAR project using the project designated standard methods. We found that the level of saprobity according to benthic macroinvertebrates was mainly linked with substrate type and stream depth. The trophic diatom index for diatoms on a soft substratum had a negative correlation with altitude and a positive correlation with distance from the source and also stream depth. There were no significant correlations between macrophyte trophic indices and environmental factors associated with stream hydrological conditions. The European fish index was influenced mainly by stream width and distance from the source, which agrees with the results of other researchers. In general, a direct or indirect role of hydrological and hydromorphological factors was evident in the forming of communities characterizing stream ecological quality.

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