Search results for "landscape conservation"
showing 10 items of 783 documents
Effects of Nile Tilapia (Oreochromis niloticus) on phytoplankton community structure and water quality: A short-term mesocosm study
2022
Nile tilapia is a highly invasive fish species, deliberately introduced into many lakes and reservoirs worldwide, sometimes resulting in significant ecosystem alterations. A short-term mesocosm experiment with and without Nile tilapia (Oreochromis niloticus) was designed to test the hypotheses that the presence of tilapia may affect phytoplankton community structure, increase nutrients availability in water column and deteriorate water quality. Nutrients, total suspended solids (TSS) and biomass of phytoplankton in different size classes (as Chl a) were measured. We found that tilapia increased the total nitrogen (TN), total dissolved nitrogen (TDN), NH4 + and TSS concentrations, deteriorat…
Plastic adjustments of biparental care behavior across embryonic development under elevated temperature in a marine ectotherm
2021
Abstract Phenotypic plasticity in parental care investment allows organisms to promptly respond to rapid environmental changes by potentially benefiting offspring survival and thus parental fitness. To date, a knowledge gap exists on whether plasticity in parental care behaviors can mediate responses to climate change in marine ectotherms. Here, we assessed the plasticity of parental care investment under elevated temperatures in a gonochoric marine annelid with biparental care, Ophryotrocha labronica, and investigated its role in maintaining the reproductive success of this species in a warming ocean. We measured the time individuals spent carrying out parental care activities across three…
Geographical assemblages of European raptors and owls
2008
Abstract In this work we look for geographical structure patterns in European raptors (Order: Falconiformes) and owls (Order: Strigiformes). For this purpose we have conducted our research using freely available tools such as statistical software and databases. To perform the study, presence–absence data for the European raptors and owl species (Class Aves) were downloaded from the BirdLife International website. Using the freely available “pvclust” R-package, we applied similarity Jaccard index and cluster analysis in order to delineate biogeographical relationships for European countries. According to the cluster of similarity, we found that Europe is structured into two main geographical…
Strategies to Mitigate the Effects of Soil Physical Disturbances Caused by Forest Machinery: a Comprehensive Review
2022
Abstract Purpose of Review Ground-based mechanized forest operations can cause severe soil disturbances that are often long lasting and detrimental to the health of forested ecosystems. To reduce these soil disturbances, focus is being increasingly directed at identifying and using appropriate mitigation techniques. This systematic review considered 104 scientific articles and reported the main findings according to four core themes: terrain-related factors, operational planning, machine modifications, and types of amendments used to mitigate machine-induced soil impacts. Recent Findings For terrain-related factors, most severe disturbances occur on machine operating trails exceeding 20% sl…
An overestimated relationship? Violent political unrest and tourism foreign direct investment in the Middle East
2010
Although the tourism industry is increasingly globalising, empirical research on the accompanying foreign direct investment (FDI) is surprisingly lacking. Furthermore, the nexus of political risk, violent political unrest and tourism FDI has been relatively neglected. Using Egypt as a heuristic case study and adopting a qualitative methodology, this paper explores the question of how political risk and violent political unrest influence tourism FDI. Surprisingly, the results are not able to corroborate a clear relationship between the two. In contrast, these results indicate that the role of stability and security for tourism FDI in developing countries has largely been overestimated in the…
Ecological and human health risks appraisal of metal(loid)s in agricultural soils: a review
2019
Agriculture is one of the major human activities that changed the landforms, water resources and the biogeochemical cycles. Pollution of agricultural soilsby metal(loid)s is a serious and global hazard but worldwide studies related to metal(loid)s pollution in agricultural soils are very limited. To fulfil this gap, metal(loid)s content in agricultural soils from 2001 to 2019 all over the world was reviewed. Multivariate statistical techniques, contamination indices and human health risk assessment were determined for the metal(loid)s. Among the analysed metal(loid)s, the average contents of Zn, Cu, Pb, Cr, Cd, As and Ni exceeded the Canadian, and China soil guidelines limits. The results o…
Dynamic Animal Populations in Managed Forests: Species Ecological Requirements and Sustainable Harvesting
2015
Forest management has altered forested environments and provoked stress to many natural habitats and biodiversity. The goal of biodiversity management is the long-term persistence of populations in human-modified environments. We demonstrate a spatio-temporal modeling approach to address the relationship between various management objectives and population persistence in the long-term in a commercial forest landscape. We used the flying squirrel (Pteromys volans), the three-toed woodpecker (Picoides tridactylus) and the long-tailed tit (Aegithalos caudatus) as example species. They are all forest species but they have distinctly different habitat requirements. In the model, forest growth, f…
Disparate movement behavior and feeding ecology in sympatric ecotypes of Atlantic cod
2021
Abstract Coexistence of ecotypes, genetically divergent population units, is a widespread phenomenon, potentially affecting ecosystem functioning and local food web stability. In coastal Skagerrak, Atlantic cod (Gadus morhua) occur as two such coexisting ecotypes. We applied a combination of acoustic telemetry, genotyping, and stable isotope analysis to 72 individuals to investigate movement ecology and food niche of putative local “Fjord” and putative oceanic “North Sea” ecotypes—thus named based on previous molecular studies. Genotyping and individual origin assignment suggested 41 individuals were Fjord and 31 were North Sea ecotypes. Both ecotypes were found throughout the fjord. Seven …
Towards (dis)continuity of agricultural wetlands: Latvia’s polder landscapes after Soviet productivism
2017
The concepts of agricultural regimes in advanced economies, such as productivism or non/neo/post-productivism, have been critically debated over the last decades to understand the transition and diversity of modern agriculture. We explore these concepts to understand the environmentally vulnerable landscape of agricultural wetlands in Latvia that, during the era of Soviet high modernism (productivist agricultural regime), have been converted into polders as part of a mass drainage movement. Today, these post-Soviet agro-polders can be characterised as antipodes in relation to integrity of heritage, ecology and the socio-economics of agricultural concerns. Building on case studies, wider pol…
Public provision versus private provision of industrial land: a hedonic approach
2005
Abstract This study examines the factors that explain the differences observed between the industrial land prices offered by the public sector and those offered by the private sector by means of estimating three hedonic pricing models. The results obtained show that location, defined as the distance to a highway, the distance to the city business district and the distance to the capital of the province, have an important impact on industrial land value. However, this impact is greater when private developers provide the land. Other variables considered, such as who is behind the provision of the industrial land, have an important impact on sale prices.