Acesso à terra e segurança alimentar. As perspetivas das partes rurais interessadas de Huambo, África

This paper tries to understand whether access to land in the Central Plateau of Angola can reduce hunger, poverty, food insecurity and thereby contribute to sustainable regional development. The Q Method approach based on the selection and ranking of phrases collected from local authorities allow the identification of different attitudes that constraint sustainable development related to access to land and food security. The State disagrees with the potential of small farms, Family Farms do not agree with the importance of access to land and those who have access to land disagree with the role of the market. Summing up the results of this exercise recognize that access to land is a solution to the hunger and food insecurity that is at odds with governments and the community.info:eu-repo/semantics/publishedVersio

Silages of agro-industrial by-products in lamb diets : effct on growth performance, carcass, meat quality and in vitro methane emissions

Research Areas: AgricultureABSTRACT - The use of agro-industrial by-products in animal feed is an opportunity to reduce imports, food waste and promote a clean and circular economy, turning worthless raw materials into high -quality and low-cost animal feeds, which does not compete with human food. This study aims to produce silages with by-products of carrot, sweet potato, potato, and tomato pomace and integrate them in lamb diets, replacing 50% of dry matter (DM) of a concentrate-based diet. Effects on growth performance, meat quality and methane production were evaluated. Three silages were produced using 350 g/kg tomato pomace, 200 g/kg wheat bran, 150 g/kg alfalfa hay and 300 g/kg potato (Psil) or 300 g/kg sweet potato (SPsil) or 300 g/kg carrot (Csil). Thirty-two lambs were housed individually and divided into four groups (8 animals/group) on the following diets: Control -850 g/kg concentrate and 150 g/kg hay; P -500 g/kg concentrate and 500 g/kg Psil in DM; SP - 500 g/kg concentrate and 500 g/kg SPsil in DM; C - 500 g/kg concentrate and 500 g/kg Csil in DM. The trial lasted 6 weeks after 1 week of adaptation. Methane production was assessed in vitro by the Ankom system, using as inoculum rumen content samples collected individually from 6 lambs on each diet at slaughter. Diet had no effect on DM intake, average daily gain and DM conversion ratio, averaging 1055 +/- 248 g, 320 +/- 61.1 g and 3.35 +/- 0.600, respectively. Also, carcass characteristics were not affected by the diet except for the lightness of subcutaneous fat which was increased by the silage diets (L* value, P = 0.016). The meat pa-rameters, pH, intramuscular fat, shear force, cooking losses and sensory attributes, were not affected by the diet. In meat color, the parameters a* and Chroma were highest in animals fed diet C, have an intermediate value with Control diet and are lowest with diets P and SP (P = 0.027 and P = 0.012, respectively). Diets had no impact on total methane emissions. The costs of the silage diets per kg live weight gain were lower than those of Control diet (P = 0.018). In summary, by-product silage can be a good option to replace concentrated feed in lamb diets without altering the growth performance and meat quality or methane production and thus contributing to the sustainability of livestock farms and the environment.info:eu-repo/semantics/publishedVersio

The effects of climate change on the hydrology and groundwater of Terceira island (Azores)

Until recently the water flowing from rain fed springs was abundant enough on Terceira (Azores, Portugal) and groundwater exploration was limited to the Lajes basin. This paper discusses the effects of climate change on the hydrology of Terceira and presents an estimate of the size of the fresh water lens underneath the whole island of Terceira using fault orientation as an indication for conductivity anisotropy. Longer periods of drought are thought to be one of the effects of greenhouse warming for Terceira and the exploration and exploitation of the freshwater lens may become necessary

Impacts of agriculture and dairy farming on groundwater quality: An optimization problem

A decision model for groundwater quality preservation in areas affected by intensive agriculture and dairy farming, with specific reference to the Azores islands, is presented. In these islands, the exigency to find appropriate instruments to support decisions in Integrated Water Management (IWM) is particularly felt because the increase of tourism and the dairy farming have increased water demands and depletion of water quality. An optimization problem, in terms of decision variables, objectives, and constraints is formalized. The physical/chemical/ecological models are embedded as constraints in the decision model. Specifically, four types of models (hydraulic model, chemical model, agricultural model, and dairy farming model) are integrated and defined. Hydrological data are used to build the hydraulic model that influences the transport and the dilution of pollutants in the groundwater. The chemical model is influenced by the amount of fertilizers and waste from animals used for yield production in the fields (agricultural model). Finally, the dairy farming model influences the agricultural model because of the presence of animals and at the same time is influenced by the available quantity of food produced in the area. The objective function is the maximization of milk production. The other objectives to be taken into account are transformed into constraints: limits on pollutant concentration in the aquifer, on minimum water demand requirements, on the quantity of used fertilizers. The optimisation problem is non linear with non-linear constraints and continuous decision variables. The decision model has been applied to a case study of Terceira Island

An integrated methodology to assess future water resources under land use and climate change: an application to the Tahadart drainage basin (Morocco)

The assessment of freshwater resources in a drainage basin is not only dependent on its hydrologic parameters but also on the socio-economic system driving development in the watershed area; the socio-economic aspect, that is often neglected in hydrologic studies, is one of the novelties of this study. The aim of this paper is twofold: (1) presenting an integrated working methodology and (2) studying a local case of a North African watershed where scarce field data are available. Using this integrated methodology, the effects of climate and land use change on the water resources and the economic development of the Tahadart drainage basin in Northern Morocco have been evaluated. Water salinization, tourism, urbanization, and water withdrawals are a threat to water resources that will increase with future climate change. The Tahadart Basin (Morocco 1,145 km2) is characterized by rain-fed agriculture and by the presence of two water retention basins. Assessment of the effects of climate and land use change on this drainage basin was based on current and future land cover maps obtained from spatial interactions models, climate data (current and future; scenario A1b for the period 2080\u20132100), and hydrological models for water budget calculations. Land use suitability maps were designed assuming a A1b Special Report on Emissions Scenarios socio-economic development scenario. The most important conclusions for the period 2080\u20132100 are the following: (1) Freshwater availability within the watershed will likely be affected by a strong increase in evaporation from open water surface bodies due to increased temperature. This increase in evaporation will limit the amount of freshwater that can be stored in the surface reservoirs. (2) Sea level rise will cause flooding and salinization of the coastal area. (3) The risk for drought in winter is likely to increase. The methodology used in this paper is integrated into a decision support tool that is used to quantify change in land use and water resources

Análise custo viagem de roteiros subaquáticos (de Apneia) na Praia da Marinha (Algarve)

Pretendeu-se definir o valor da utilização recreativa de mergulho em apneia, em três roteiros implementados na Praia da Marinha, Algarve. Utilizou-se o método do custo de viagem para definir o valor de uso e os benefícios de recursos naturais utilizados para esta actividade de recreação. Validaram-se 115 inquéritos efectuados entre 15/07 a 15/9 de 2008, analisando-se os dados pelo modelo de regressão. Considerou-se como variável independente o número de mergulhos efectuados e como variável dependente os diversos custos, considerando o tempo dispendido na actividade ponderado por uma fracção do rendimento declarado. Concluiu-se que o excedente médio por mergulho é de 5,0 €, pelo que o valor de uso dos roteiros é de 600 €/ano, correspondente a um total de 30000 € admitindo uma taxa de desconto de 2% e a manutenção do recurso por muitos anos. Com uma capacidade de carga de 1.000 mergulhos por ano, a renda total do recurso por ano passa a ser de 5000 € e o valor económico total de 250000 €.info:eu-repo/semantics/publishedVersio

Potential of Cistus ladanifer L. (rockrose) in small ruminant diets - effect of season and plant age on chemical composition, in vitro digestibility and antioxidant activity

Shrubs can provide an important contribution to the fodder resources for small ruminants in Mediterranean areas, but there is limited information on their feed value, including secondary metabolites and their seasonal differences. This study evaluated the effect of seasonal variation in chemical composition, in vitro digestibility and antioxidant activity of the aerial parts of plants of Cistus ladanifer of two age groups [young plants vs. older ones (2-6 years old)]. Aerial parts of C. ladanifer plants of both age groups were characterized by moderate cell-wall content [321-410 g NDF kg(-1) dry matter (DM)], high levels of phenolic compounds (55.1-106 g gallic acid equivalents per kg DM) and condensed tannins (CT) (32.1-161 g kg(-1) DM), low protein content (55-100 g kg(-1) DM) and low digestibility (249-315 g of digestible organic matter per kg DM). During autumn and winter, C. ladanifer showed higher protein levels and lower cell-wall content than in the other seasons. The highest values of phenolic compounds, CT and antioxidant activity were achieved during summer. Young plants showed higher levels of phenolic compounds during spring, summer and winter, and higher CT contents in summer (more than 54 g kg(-1) DM) compared to old plants. Aerial parts of C. ladanifer of both age groups may be used as a component of ruminant nutrition, but only as a supplement and associated with other feeding resources to complement its nutritional imbalances

Identification, definition and quantification of goods and services provided by marine biodiversity: Implications for the ecosystem approach

This paper identifies and defines ecosystem goods and services provided by marine biodiversity. Case studies have been used to provide an insight into the practical issues associated with the assessment of marine ecosystem goods and services at specific locations. The aim of this research was to validate the definitions of goods and services, and to identify knowledge gaps and likely difficulties of quantifying the goods and services. A validated theoretical framework for the assessment of goods and services is detailed, and examples of the goods and services at a variety of case study areas are documented. These results will enable future assessments of marine ecosystem goods and services. It is concluded that the utilisation of this goods and services approach has the capacity to play a fundamental role in the Ecosystem Approach, by enabling the pressures and demands of society, the economy and the environment to be integrated into environmental management