Search results for " Fish"
showing 10 items of 1414 documents
Preface: Proceedings of the 14th IASWS international conference
2018
Preface to the Proceedings of the 14th IASWS international conference
Deducing a Drain Spacing Formula by Applying Dimensional Analysis and Self-Similarity Theory
2016
For designing a steady state drainage system a drain flow formula coupled with the Dupuit-Forcheimer form of the differential equation of groundwater flow is used. At first, in this paper the most applied drain flow formulas in steady-state conditions are reviewed and compared using as dependent variable the ratio between the maximum water table height and the distance between two lines of parallel drains. These equation are also tested using experimental field data measured in three plot drained by surface pipe drains having different value of drain spacing. Then, applying the dimensional analysis and the self-similarity theory, a new drain spacing formula is theoretically deduced and comp…
Aquaculture in Sicily: the state of the art
2009
Aquaculture in Sicily, represented almost exclusively by seabass and sea bream production, together with capture fishery, plays a significant role in the regional economy. On a national basis, the regional production covers about 20% of Italian euryha- line fish production. Fingerling supply is guaranteed by the two hatcheries present on the Island. Twelve floating cage farms and two inshore farms annually produce about 4,000 t of fish. A small extensive production arises from the storage basins of the salt work of Trapani. This niche production could represent an opportunity to realize a new distinctive organic aquaculture, preferred by the consumers respect to intensive produced fish, tha…
Sustainable vineyard floor management: An equilibrium between water consumption and soil conservation
2018
Abstract Sustainable vineyards soil management can help to mitigate the negative effect of intensive agriculture on soil ecosystem for the achievement of the sustainable development goals. Cover crops use as cover management in vineyard could be considered as nature based solution for soil restoration and proper water management. Cover crops (CC) provide many ecosystem services through carbon sequestration and climate change regulation, water purification and soil protection. However, a holistic approach is needed to understand the maximum potential ecosystem service that can be provided in different soil and climatic condition also considering vineyard needs. The current knowledge of CC ma…
Soil Mapping and Processes Modeling for Sustainable Land Management
2017
Soil maps and models are indispensable tools in sustainable land management. The sustainable land use of our territory is fundamental to providing long-term socio-economic and environmental benefits. The risk of land degradation and corresponding declines in ecosystem services depends on the type of land use. Soil restoration can be extremely expensive, more than the implementation of sustainable land use practices. This is especially important in the context of climate change and the increasing pressure that a growing population places on soil resources, which is a global phenomenon. The objective of this chapter is to show the advantages of using soil mapping and modeling in sustainable l…
Soil Mapping and Processes Models for Sustainable Land Management Applied to Modern Challenges
2017
Abstract In the context of growing population and global change, increasing demands for food production are an enormous challenge that we face in the modern world. At the same time the need to prevent land degradation, restore lands that are already degraded, and maintain soil quality and health is critical to a sustainable use of land resources. Accurate maps and adequate models are indispensable tools to assist managers, scientists, and decision makers in addressing these challenges. In this chapter, we outline the main impacts of climate change on soils, key adaptation, and mitigation strategies and provide an overview of key issues in sustainable agricultural production as well as land …
Adaptive radiation along a thermal gradient: preliminary results of habitat use and respiration rate divergence among whitefish morphs.
2014
Adaptive radiation is considered an important mechanism for the development of new species, but very little is known about the role of thermal adaptation during this process. Such adaptation should be especially important in poikilothermic animals that are often subjected to pronounced seasonal temperature variation that directly affects metabolic function. We conducted a preliminary study of individual lifetime thermal habitat use and respiration rates of four whitefish (Coregonus lavaretus (L.)) morphs (two pelagic, one littoral and one profundal) using stable carbon and oxygen isotope values of otolith carbonate. These morphs, two of which utilized pelagic habitats, one littoral and one …
Recent progress in understanding cholinergic function at the cellular and molecular levels
1992
Cholinergic transmission can claim to be the first form of chemical neurotransmission to be investigated by pharmacological and electrophysiological methods and the first in which both the transmitter and its receptor have been isolated and characterized. One reason for this is that neuromuscular transmission is cholinergic and the neuromuscular junction (especially that of frogs) is a readily investigated synapse in which responses are recorded by a muscular twitch — something which can be appreciated by direct observation and which does not require sophisticated equipment. Another is that in the form of the electric organs of strongly electric fish Nature has provided a tissue embryologic…
In Situ X-Ray Tomography Imaging of Soil Water and Cyanobacteria From Biological Soil Crusts Undergoing Desiccation
2018
Biological soil crusts (biocrusts) are millimeter-sized microbial communities developing on the topsoils of arid lands that cover some 12% of Earth’s continental area. Biocrusts consist of an assemblage of mineral soil particles consolidated into a crust by microbial organic polymeric substances that are mainly produced by the filamentous bundle-forming cyanobacteria, among which Microcoleus vaginatus is perhaps the most widespread. This cyanobacterium is the primary producer for, and main architect of biocrusts in many arid soils, sustaining the development of a diverse microbial community. Biocrusts are only active when wet, and spend most of their time in a state of desiccated quiescence…
Soil Erosion Induced by the Introduction of New Pasture Species in a Faxinal Farm of Southern Brazil
2018
The faxinal management system is an endangered agro-silvopastoral system which forms part of the local traditional management in the Paraná federal state (Brazil). Significant changes in land management since the 1970s caused farmers to look for alternatives to increase the productivity of their farms. The introduction of new pasture species is causing land degradation problems, of which soil erosion is the most important challenge. Therefore, in this study, we assessed the environmental consequences of introducing exotic pasture species, such as Brachiaria decumbens. To achieve this goal, ten erosion plots were installed with exotic and native pastures (Paspalum notatum Flügg&e…