Search results for "Diversity index"
showing 8 items of 28 documents
Metagenomics Analysis Reveals an Extraordinary Inner Bacterial Diversity in Anisakids (Nematoda: Anisakidae) L3 Larvae
2021
This article belongs to the Special Issue Parasitic Diseases from Wild Animals with Emphasis in Zoonotic Infections.
Biodiversidad en el Siglo XXI: más allá del conteo de especies
2018
In modern ecology, the traditional diversity indexes (usually of richness, abundance, and species evenness) have been highly revealing and useful for monitoring community and ecosystem processes. However, around two decades ago, a pioneering research team noticed that these indexes did not completely resolve their open questions. Thus, they suggested changing the way biodiversity was measured. At its base, this new methodology considers the distance between species (in phylogenetic or functional terms) before subsequently applying the appropriate biodiversity indexes. Including phylogenetic and functional elements in the evaluation of diversity allows us to approach the concept of biodivers…
Seawater carbonate chemistry and community structure of marine biofouling communities
2018
Ocean acidification may have far-reaching consequences for marine community and ecosystem dynamics, but its full impacts remain poorly understood due to the difficulty of manipulating pCO2 at the ecosystem level to mimic realistic fluctuations that occur on a number of different timescales. It is especially unclear how quickly communities at various stages of development respond to intermediate-scale pCO2 change and, if high pCO2 is relieved mid-succession, whether past acidification effects persist, are reversed by alleviation of pCO2 stress, or are worsened by departures from prior high pCO2 conditions to which organisms had acclimatized. Here, we used reciprocal transplant experiments al…
Shallow water marine sediment bacterial community shifts along a natural CO2 gradient in the Mediterranean Sea Off vulcano, Italy
2014
The effects of increasing atmospheric CO(2) on ocean ecosystems are a major environmental concern, as rapid shoaling of the carbonate saturation horizon is exposing vast areas of marine sediments to corrosive waters worldwide. Natural CO(2) gradients off Vulcano, Italy, have revealed profound ecosystem changes along rocky shore habitats as carbonate saturation levels decrease, but no investigations have yet been made of the sedimentary habitat. Here, we sampled the upper 2 cm of volcanic sand in three zones, ambient (median pCO(2) 419 µatm, minimum Omega (arag) 3.77), moderately CO(2)-enriched (median pCO(2) 592 µatm, minimum Omega (arag) 2.96), and highly CO(2)-enriched (median pCO(2) 1611…
Komunitas Gastropoda pada Padang Lamun Perairan Pantai Manokwari
2021
Penelitian ini bertujuan mengidentifikasi dan menganalisa struktur komunitas gastropoda di pesisir pantai Manokwari. Pengambilan sampel menggunakan metode transek di dua stasiun pengamatan yaitu Pantai Briosi BLK dan Pantai Rendani. Setiap stasiun diletakkan tiga garis transek ke arah laut dan setiap transek terdiri atas 10 kuadrat. Transek ini diletakkan di atas padang lamun. Analisis data dilakukan meliputi indeks keanekaragaman, indeks keseragaman, dominasi dan kepadatan gastropoda. Hasil penelitian menunjukkan ditemukan bahwa kualitas perairan di kedua lokasi sampling dapat mendukung pertumbuhan gastropoda. Komposisi spesies gastropoda yang ditemukan pada kedua lokasi sampling meliputi …
Physico-chemical and bacteriological parameters in a hypereutrophic lagoon (Albufera Lake, Valencia, Spain).
1991
Several physico-chemical parameters related to water quality, as well as saprophytic and public health-related heterotrophic bacterial groups were studied in a hypereutrophic lake (Albufera, Valencia) at different seasons. Total microscopic and viable counts were compared, and, together with faecal indicators, were determined in water samples from different sites. Heterotrophic bacteria grown on nonselective medium were identified to genus level and a diversity index was calculated. Pseudomonas-Alcaligenes was the most frequently isolated group from all sampling sites along the study, following by Moraxella, Acinetobacter, Vibrio and Aeromonas. The relationships between all parameters were …
Impact of various factors on the diversity of soil microorganisms in agricultural and forest soils
2014
Elektroniskā versija nesatur pielikumus
The “genetic erosion” of the soil ecosystem
2013
Abstract This paper takes into consideration the influence of human activities on the loss of pedodiversity in a Mediterranean area due to large scale farming. In particular it examines the quantitative and qualitative soil changes in a period of 53 years (from 1955 to 2008) evaluating the loss of soil diversity at soil subgroups level of the USDA Soil Taxonomy system. The following indices were used: richness; Shannon’s diversity index; Simpson diversity index; Shannon’s evenness index; Simpson’s evenness index. In this case study, considering what we observed in time, the human intervention in soil transformation could increase the diversity in the landscape in an initial phase, but forwa…