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... Fish schools reduce their predators' encounter rates not only by performing evasive maneuvers but also by increasing distances between prey patches. However, a similar challenge applies to isolated prey fish seeking refuge during periods of diel school formation. We demonstrate with an Ideal Gas movement model that as the stock sizes of a fish who forms schools daily decreases, school densities do ...
... The accounting of aluminum in-use stocks (ALIS) has received widespread attention, but the systematic assessment of China's ALIS at the provincial level remains unclear. Based on a bottom-up approach, this study utilizes Henan Province as an example to investigate the ALIS and its spatial patterns at China's provincial level. In 2017, the total and per capita of ALIS in Henan were 12 Tg and 125 kg ...
stockingrate, etc ; environmental economics; fish; fisheries management; renewable resources; resource management; Show all 6 Subjects
Abstract:
... This article analyses the effect of productivity improvements on optimal fisheries management. It is shown that when harvest costs are independent of resource stock and the stock is below its steady state level, then for any given stock it is optimal to reduce harvest levels in response to a productivity increase unless optimal harvest rate is already zero. If harvest costs are stock dependent thi ...
stockingrate, etc ; Anguilla anguilla; eel; juveniles; population dynamics; research; Baltic Sea; Show all 7 Subjects
Abstract:
... According to the recruitment indices provided by ICES for the years 2011–2021, the natural recruitment of the European eel remains at low level. However, fishery-dependent data series indicate an increasing trend in the southern Baltic Sea within recent years. In the light of the pan-European conservation efforts, the question is whether fishery-independent monitoring approaches can verify this po ...
stockingrate, etc ; autumn; ecological restoration; herds; landscapes; national parks; shrubs; spring; summer; wetlands; Show all 10 Subjects
Abstract:
... Wetlands are often exposed to reed and shrub expansion that dominate their heterogeneous landscape and threaten species inhabiting open wetlands. The alternative to heavy‐machine mowing is grazing, which should be carried out without fencing in high‐value protected areas. To evaluate the effectiveness of semi‐free‐ranging cattle in sustaining and restoring the open landscape of heterogeneous wetla ...
stockingrate, etc ; fish; fisheries; freshwater; habitats; landscapes; population dynamics; population size; research; sport fishing; sports; variance; Show all 12 Subjects
Abstract:
... In commercial and recreational fisheries, catch rate is often assumed to be proportional to stock size and is used by managers and fishers as an indicator of fishery sustainability. If catch rate is proportional to stock size, it can signal a decline of stocks and managers can impose restrictive harvest policies or recreational anglers can move to a new system and allow the over-exploited system t ...
... Soil organic carbon (SOC) plays a crucial role in physical, chemical and biological soil properties and maintains the sustainability of cropping systems. However, SOC stocks in croplands decline due to lower carbon inputs and faster decomposition rates. Therefore, sustainable soil management (SSM) practices are crucial to replenish the carbon inputs. Mapping carbon (C) stocks and sequestration pot ...
stockingrate, etc ; Escherichia; Staphylococcus; Streptococcus; cows; dairy industry; drainage; etiology; feces; hygiene; mastitis; risk; sanitation; therapeutics; udders; veterinary medicine; Bangladesh; India; Pakistan; Sri Lanka; Show all 20 Subjects
Abstract:
... Mastitis is a major production disease, causing significant economic losses for dairy farmers in South-Asian countries, as well as other parts of the world. Udder health control programs (UHCP) have been established in developed countries as an effective strategy for mastitis control but have not yet been introduced in South-Asian low-income countries like Bangladesh, India, Pakistan, and Sri Lank ...
stockingrate, etc ; bioeconomic models; equations; prices; Show all 4 Subjects
Abstract:
... In this paper, we study a mathematical bio-economic model of a fishery with varying price. The three dimensional model describes the time evolution of the resource, the fishing effort and the price. The model is original because it considers a nonlinear harvesting function assumed to depend upon stock size and fishing effort with a saturation effect with respect to the resource as well as a price ...
Anna Rindorf; Mikael van Deurs; Daniel Howell; Eider Andonegi; Aaron Berger; Bjarte Bogstad; Noel Cadigan; Bjarki Þór Elvarsson; Niels Hintzen; Marie Savina Roland; Marc Taylor; Vanessa Trijoulet; Tobias van Kooten; Fan Zhang; Jeremy Collie
stockingrate, etc ; biomass; marine fish; prediction; probability; Show all 5 Subjects
Abstract:
... The correct prediction of the shape and strength of density dependence in productivity is key to predicting future stock development and providing the best possible long‐term fisheries management advice. Here, we identify unbiased estimators of the relationship between somatic growth, recruitment and density, and apply these to 80 stocks in the Northeast Atlantic. The analyses revealed density‐dep ...
stockingrate, etc ; cross immunity; education; farmers; genetic variation; human population; industry; linear models; molecular epidemiology; phylogeography; porcine reproductive and respiratory syndrome; prioritization; swine; trade; vaccination; viruses; Europe; Show all 17 Subjects
Abstract:
... Porcine reproductive and respiratory syndrome (PRRS) is among the most devastating diseases affecting the pig industry. Despite vaccines having been available for decades, the remarkable genetic variability of this virus, leading to poor cross‐protection, has limited their efficacy, and other measures must be adopted to effectively control the viral circulation. Some recent studies have investigat ...
stockingrate, etc ; carbon; carbon sinks; climate change; cropland; food security; forests; grasslands; humus; land use; meteorology; mineral soils; overstory; silvopastoral systems; species diversity; sustainable land management; tree age; trees; understory; Alberta; Show all 20 Subjects
Abstract:
... Agroforestry systems (AFS) are increasingly being recognized as sustainable land-use systems that can increase carbon (C) sequestration and improve food security. However, the relative contributions of various C pools to the overall C stock of AFS and their dependence on factors such as tree age, species diversity and density is still unclear in many regions. Using an equivalent soil mass approach ...
stockingrate, etc ; Coregonus; egg production; fecundity; gillnets; lakes; mortality; risk; Show all 8 Subjects
Abstract:
... Vendace is commonly assumed at low risk to recruitment overfishing. This assumption has been confirmed for boreal stocks but might not apply at lower latitudes. We evaluated the risk of recruitment overfishing at the southernmost extent of vendace populations by comparing fecundity, natural mortality, and fishing mortality of two stocks differing in growth with those of a population not subject to ...
stockingrate, etc ; biodiversity; clearcutting; forests; habitat fragmentation; landscapes; politics; socialism; wood; Poland; Show all 10 Subjects
Abstract:
... At all times, historical, political, economic, and social factors have affected the management of forests, with direct and indirect effects on the landscape. This study aimed to trace the impact of Poland’s forestry evolution over the last 75 years (1945–2020) on forest biodiversity at the landscape level. Five indicators were selected (forest area, forest fragmentation, protected forests, protect ...
stockingrate, etc ; Mallotus villosus; fish; research; time series analysis; uncertainty; Barents Sea; Show all 7 Subjects
Abstract:
... It is assumed that maturation in the Barents Sea capelin is length-dependent, and that fish of at least 14 cm will potentially spawn. Current assessment and management models for the stock are based on this assumption of constant maturity at length (MaL). Using data from scientific surveys, this paper examines the validity of the constant MaL assumption, and contrasts it with maturation based on e ...
... Forest conversion can drastically impact carbon (C) and nutrient processes and microbial stoichiometry, which will modify soil organic C (SOC) stock. However, SOC stock dynamics and its underlying mechanisms induced by long-term forest conversion remain unclear. Three well-protected plantations converted from natural forests for 36 years were compared, i.e., Cryptomeria fortunei (CF), Metasequoia ...
stockingrate, etc ; Reinhardtius hippoglossoides; bioeconomics; boats; fish; fisheries; growth models; income; research; Greenland; Show all 10 Subjects
Abstract:
... The North Atlantic Fisheries Organization (NAFO) has continuously lowered their advice regarding the Total Allowed Catch (TAC) for the coastal Greenland halibut fisheries in Western Greenland. This is due to concerns of overexploitation of the fishery. This paper investigates how the fishing intensity in the fishery for Greenland halibut (Reinhardtius hippoglossoides) in the Disko Bay, Greenland, ...
stockingrate, etc ; cattle; ecosystems; forage; grasslands; greenhouses; pasture management; pastures; rangelands; soil carbon; Canada; Show all 11 Subjects
Abstract:
... Significant interest exists in the potential for specialized grazing systems, including adaptive multipaddock (AMP) grazing, to enhance grassland health and function. However, specific pasture management practices associated with AMP grazing at the ranch level remain poorly understood in comparison with more regionally representative management systems. As part of a larger study examining grazing ...
stockingrate, etc ; Markov chain; biomass; economic performance; fish; fisheries; issues and policy; research; uncertainty; Show all 9 Subjects
Abstract:
... This paper deals with mathematical modelling of strategies in harvesting of fish populations. Since too aggressive harvesting may have severe consequences, a cautious control of the process is called for. The determination of optimal harvesting based on the biomass size is made even more challenging since there is considerable uncertainty in the estimation of the stock size, the so-called incomple ...
stockingrate, etc ; carbon dioxide; cattle; ecosystems; grasslands; greenhouse gases; soil density; soil water content; Alberta; Show all 9 Subjects
Abstract:
... Adaptive multi-paddock (AMP) grazing, a grazing system in which individual paddocks are grazed for a short duration at a high stock density and followed by a long rest period, is claimed to be an effective tool to sustainably manage and improve grasslands and enhance their ecosystem services. However, whether AMP grazing is superior to conventional grazing (n-AMP) in reducing soil greenhouse gas ( ...