Search results for "Transect"

How livestock grazing affects vegetation structures and small mammal distribution in the semi-arid Karoo

2000

In this study we investigated vegetation changes superimposed by grazing and their effect on small mammals in the Karoo (South Africa) on grazed farmland and an adjacent, 10-year livestock enclosure. Plains and drainage line habitats were compared by monitoring vegetation height and cover, and small mammal species composition and abundance along transects. Animals were captured by live trapping. Vegetation cover was low on the grazed compared to the ungrazed study site, but vegetation height did not differ. The number of small mammal individuals and the number of species captured was higher at the ungrazed study site. Two species of climbing rodents captured in the ungrazed drainage line we…

A comparison of two methods for surveying aquatic macrophyte communities in boreal lakes: Implications for bioassessment

2013

To compare the performance of two common methods for surveying boreal lake aquatic macrophyte communities (the transect survey and the phytolittoral inventory) in lake bioassessment, we studied five small humic lakes with both methods. In addition to this pairwise comparison, we contrasted available independent sets of reference lake data of either methodological origin. Specifically, we compared the observed species richness and a number of ecological quality (community) metrics and their variability both between the methods and within them in relation to sampling effort and operator. With the phytolittoral inventory, more taxa (mean 38.8 ± s.d. 12.1) were observed than with transect surve…

Jenis-Jenis Kima dan Kelimpahannya di Perairan Amdui Distrik Batanta Selatan Kabupaten Raja Ampat

2017

Kima merupakan salah satu jenis molusca laut yang banyak ditemukan di perairan Raja Ampat. Hewan ini dilindungi di seluruh dunia termasuk di Indonesia. Penelitian ini dilakukan pada bulan Maret-April 2014, di perairan Amdui yang memiliki ekosistem terumbu karang, dan ditetapkan 3 lokasi pengamatan yaitu: Pulau Ayem, Teluk Sawawris dan Teluk Sawros. Metode yang digunakan pada penelitian ini adalah metode observasi dengan teknik belt transek, dan bertujuan untuk mengetahui jenis dan kelimpahan kima di perairan Amdui. Kima yang ditemukan di perairan laut Kampung Amdui Kabupaten Raja Ampat yaitu 8 jenis terdiri dari T. crocea, T. maxima, T. squamosa, T .gigas, H. porcellanus, H. hippopus, T. te…

Molluscan assemblages associated with photophilic algae in the Marine Reserve of Ustica Island (Lower Tyrrhenian Sea, Italy)

2000

Abstract Very few studies have addressed the effect of protection on macrozoobenthos in marine protected areas, and particularly for sites in the Mediterranean Sea. In the present study, the molluscan assemblages associated with photophilic algal communities of the Marine Reserve of Ustica Island, were investigated. A survey was carried out along transects from 1 to 15 m in depth, during the spring of 1996 at three different sites, subjected to different levels of reserve protection. Species richness and number of individuals reflected the level of protection, and both variables were significantly higher in the integral (most heavily protected) part of the reserve compared with the less wel…

Seagrass Potential In Aisandami Village Wondama Bay and It’s Management Strategy

2020

Seagrass ecosystem have primary and secondary productivity with great support to the abundance and diversity of fishes and it’s biota associations. Seagrass ecosystems are also as a coastal resources that have an important role of environmental services. Some community activities will directly or indirectly can have an impact on habitat degradation and biodiversity of seagrass ecosystems. The importance oto assess the potential of seagrass ecosystem and it’s biotas association is to know of sea grass’s role to provides of environmental services is the aim of this study. This research was conducted in the waters of Kampung Aisandami, Teluk Wondama Regency during June - July 2019. Data collec…

Granulometry, mineralogy and trace elements of marine sediments from the Gulf of Milazzo (NE Sicily): evaluation of anthropogenic impact

2010

Granulometry, mineralogy, and trace element concentrations are determined in marine sediments from thirty-six sampling sites in the littoral environment of the Gulf of Milazzo (NE Sicily). Sediment samples were collected in August 2008, along 18 seaward transects, at water depths of ‐10, ‐20 and ‐30 m, by using a Van Veen grab. Grain-size analysis shows predominance of sand (56%) and silt (35%) fractions with respect to clay (7%) and gravel (2%) fractions. Bulk mineralogical analysis documents the presence of quartz, micas, feldspars, calcite, and chlorite, which reflect erosion processes affecting the Kabilian-Calabrian Units. Concentrations of most trace elements in the deeper sediments w…

Genetic variation of European beech (Fagus sylvatica L.) along an altitudinal transect at mount Vogelsberg in Hesse, Germany

2000

Allelic and genotypic variation at 13 different enzyme loci of autochthonous European beech (Fagus sylvatica L.) was investigated in six 110-160-year-old stands growing at elevations between 150 and 660 m above sea level on the western slope of mount Vogelsberg in central Germany. The highest elevated population showed the highest number of effective alleles (Ne), the highest total heterozygosity (He) and the highest population differentiation deltaT. Also, the genotype SKD-A2A3 of shikimate dehydrogenase was significantly more frequent at the two highest elevated stands (P = 11%) than at the three lowest elevated stands (P = 1%). Further differences in genotype frequencies between 11 of 15…

Soils Along the Altitudinal Transect and in Catchments

2008

Vulnerability of Mediterranean ecosystems to Climatic Change, study of soil degradation under different climatological conditions in an altitudinal t…

1995

Abstract To investigate the potential response of soils to climatic change, measurements of soil physical and chemical properties were carried out during a year in a mountain zone in Alicante (Spain), along an altitudinal and climatological gradient. Hydrological properties (infiltration runoff and sediment concentration) were measured under winter and summer conditions. Chemical and physical soil properties were analyzed for reference soil profiles along the transect. The erosional response of the soils as well as soil properties like organic matter and CEC are found to be under the direct influence of the climate, and as a result they have to be considered as important factors in the dese…

The role of inorganic and organic nutrients on the development of phytoplankton along a transect from the Daugava River mouth to the Open Baltic, in …

2003

Abstract The importance of dissolved silicate (DSi), dissolved inorganic nitrogen (DIN), dissolved organic nitrogen (DON), phosphate and dissolved organic phosphorus (DOP) on algal growth is analysed for the Gulf of Riga and the adjacent open Baltic Sea. The results of three cruises (May, June, and July, 1999) along a transect across the Gulf of Riga from the entrance to the Daugava River to the open Baltic are presented. Nutrient-limitation was identified on the basis of available nutrient concentrations and stoichiometric analysis. In spring, phosphate appeared to be the algal-growth-potential-limiting nutrient at the entrance of the Daugava River, DSi in the central Gulf, and DIN at the …