605 resultados para Landwirtschaft
Resumo:
Adoption of new cattle management practices by Indonesian smallholders occurs less as a ‘technology transfer’ in the classical sense but rather as a series of conscious decisions by farming households weighing risks and resources as well as matching innovations to livelihood strategies. This paper uncovers the context of decisions and communication of innovations by way of social networks. The research looks at two geographically distinct cases where new cattle management practices have been introduced. We apply the lens of a common sense framework initially introduced by Clifford Geertz. Smallholder decisions are analysed within a socio-cultural context and a particular set of resources, risks and livelihood objectives. We show that the respective value placed on land, cattle and food security is central to adoption of new cattle management techniques. Far from accepting everything novel, smallholders are selective and willing to make changes to their farming system if they do not conflict with livelihood strategies. Innovations are communicated through a range of existing social networks and are either matched to existing livelihood strategies or perceived as stepping-stones out of agriculture.
Experimental and modeling studies of forced convection storage and drying systems for sweet potatoes
Resumo:
Sweet potato is an important strategic agricultural crop grown in many countries around the world. The roots and aerial vine components of the crop are used for both human consumption and, to some extent as a cheap source of animal feed. In spite of its economic value and growing contribution to health and nutrition, harvested sweet potato roots and aerial vine components has limited shelf-life and is easily susceptible to post-harvest losses. Although post-harvest losses of both sweet potato roots and aerial vine components is significant, there is no information available that will support the design and development of appropriate storage and preservation systems. In this context, the present study was initiated to improve scientific knowledge about sweet potato post-harvest handling. Additionally, the study also seeks to develop a PV ventilated mud storehouse for storage of sweet potato roots under tropical conditions. In study one, airflow resistance of sweet potato aerial vine components was investigated. The influence of different operating parameters such as airflow rate, moisture content and bulk depth at different levels on airflow resistance was analyzed. All the operating parameters were observed to have significant (P < 0.01) effect on airflow resistance. Prediction models were developed and were found to adequately describe the experimental pressure drop data. In study two, the resistance of airflow through unwashed and clean sweet potato roots was investigated. The effect of sweet potato roots shape factor, surface roughness, orientation to airflow, and presence of soil fraction on airflow resistance was also assessed. The pressure drop through unwashed and clean sweet potato roots was observed to increase with higher airflow, bed depth, root grade composition, and presence of soil fraction. The physical properties of the roots were incorporated into a modified Ergun model and compared with a modified Shedd’s model. The modified Ergun model provided the best fit to the experimental data when compared with the modified Shedd’s model. In study three, the effect of sweet potato root size (medium and large), different air velocity and temperature on the cooling/or heating rate and time of individual sweet potato roots were investigated. Also, a simulation model which is based on the fundamental solution of the transient equations was proposed for estimating the cooling and heating time at the centre of sweet potato roots. The results showed that increasing air velocity during cooling and heating significantly (P < 0.05) affects the cooling and heating times. Furthermore, the cooling and heating times were significantly different (P < 0.05) among medium and large size sweet potato roots. Comparison of the simulation results with experimental data confirmed that the transient simulation model can be used to accurately estimate the cooling and heating times of whole sweet potato roots under forced convection conditions. In study four, the performance of charcoal evaporative cooling pad configurations for integration into sweet potato roots storage systems was investigated. The experiments were carried out at different levels of air velocity, water flow rates, and three pad configurations: single layer pad (SLP), double layers pad (DLP) and triple layers pad (TLP) made out of small and large size charcoal particles. The results showed that higher air velocity has tremendous effect on pressure drop. Increasing the water flow rate above the range tested had no practical benefits in terms of cooling. It was observed that DLP and TLD configurations with larger wet surface area for both types of pads provided high cooling efficiencies. In study five, CFD technique in the ANSYS Fluent software was used to simulate airflow distribution in a low-cost mud storehouse. By theoretically investigating different geometries of air inlet, plenum chamber, and outlet as well as its placement using ANSYS Fluent software, an acceptable geometry with uniform air distribution was selected and constructed. Experimental measurements validated the selected design. In study six, the performance of the developed PV ventilated system was investigated. Field measurements showed satisfactory results of the directly coupled PV ventilated system. Furthermore, the option of integrating a low-cost evaporative cooling system into the mud storage structure was also investigated. The results showed a reduction of ambient temperature inside the mud storehouse while relative humidity was enhanced. The ability of the developed storage system to provide and maintain airflow, temperature and relative humidity which are the key parameters for shelf-life extension of sweet potato roots highlight its ability to reduce post-harvest losses at the farmer level, particularly under tropical climate conditions.
Resumo:
In Colombia coffee production is facing risks due to an increase in the variability and amount of rainfall, which may alter hydrological cycles and negatively influence yield quality and quantity. Shade trees in coffee plantations, however, are known to produce ecological benefits, such as intercepting rainfall and lowering its velocity, resulting in a reduced net-rainfall and higher water infiltration. In this case study, we measured throughfall and soil hydrological properties in four land use systems in Cauca, Colombia, that differed in stand structural parameters: shaded coffee, unshaded coffee, secondary forest and pasture. We found that throughfall was rather influenced by stand structural characteristics than by rainfall intensity. Lower throughfall was recorded in the shaded coffee compared to the other systems when rain gauges were placed at a distance of 1.0 m to the shade tree. The variability of throughfall was high in the shaded coffee, which was due to different canopy characteristics and irregular arrangements of shade tree species. Shaded coffee and secondary forest resembled each other in soil structural parameters, with an increase in saturated hydraulic conductivity and microporosity, whereas bulk density and macroporosity decreased, compared to the unshaded coffee and pasture. In this context tree-covered systems indicate a stronger resilience towards changing rainfall patterns, especially in mountainous areas where coffee is cultivated.
Resumo:
The effect of charcoal feeding on manure quality and its subsequent application to enhance soil productivity has received little attention. The objectives of the present study therefore were to investigate the effects of (i) charcoal feeding on manure composition, and (ii) charcoal-enriched manure application on soil fertility parameters and growth of millet (Pennisetum glaucum L.). To this end, two experiments were conducted: First, a goat feeding trial where goats were fed increasing levels of activated charcoal (AC; 0, 3, 5, 7, and 9% of total ration); second, a greenhouse pot experiment using the manure from the feeding trial as an amendment for a sandy soil from northern Oman. We measured manure C, N, P, and K concentrations, soil fertility parameters and microbial biomass indices, as well as plant yield and nutrient concentrations. Manure C concentration increased significantly (P<0.001) from 45.2% (0% AC) to 60.2% (9% AC) with increasing dietary AC, whereas manure N, P, and K concentrations decreased (P<0.001) from 0% AC (N: 2.5%, P: 1.5%, K: 0.8%) to 9% AC (N: 1.7%, P: 0.8%, K: 0.4%). Soil organic carbon, pH, and microbial biomass N showed a response to AC-enriched manure. Yield of millet decreased slightly with AC enrichment, whereas K uptake was improved with increasing AC. We conclude that AC effects on manure quality and soil productivity depend on dosage of manure and AC, properties of AC, trial duration, and soil type.
Resumo:
Changes in soil sulfur (S) fractions were assessed in oil palm and food garden land use systems developed on forest vegetation in humid tropical areas of Popondetta in northern Province. The study tested a hypothesis that S in food gardens are limiting nutrient factor and are significantly lower than in plantations and forests. Subsistence food gardens are under long-term slash and burn practice of cropping and such practice is expected to accelerate loss of biomass S from the ecosystem. From each land use, surface soil (0–15 cm) samples were characterised and further pseudocomplete fractionated for S. Conversion of forest to oil palm production decreased (p<0.001) soil pH and electrical conductivity values. The reserve S fraction in soil increased significantly (p<0.05) due to oil palm production ( 28 %) and food gardening activity (∼ 54 %). However, plant available SO42--S was below 15 mg kg^(−1) in the food garden soils and foliar samples of sweet potato crop indicating deficiency of plant available S. Soil organic carbon content (OC) was positively and significantly correlated to total S content (r=0.533; p<0.001) among the land use systems. Thus, crop management practices that affect OC status of the soils would potentially affect the S availability in soils. The possible changes in the chemical nature of mineralisable organic S compounds leading to enhanced mineralisation and leaching losses could be the reasons for the deficiency of S in the food garden soils. The results of this study conclude that long-term subsistence food gardening activity enriched top soils with reserve S or total S content at the expense of soluble S fraction. The subsistence cropping practices such as biomass burning in food gardens and reduced fallow periods are apparently threatening food security of oil palm households. Improved soil OC management strategies such as avoiding burning of fallow vegetation, improved fallows, mulching with fallow biomass, use of manures and S containing fertilisers must be promoted to sustain food security in smallholder oil palm system.
Resumo:
The demands of mitigation and adaptation policies are important to understanding a country’s climate change preparation by providing microfinance in the agricultural sector. This could be seen as a strategy to fight against the challenges of future food security. In 2014, Indonesia established climate change adaptation policies. This legislation aims to pave the way for making actions on climate change adaptation mainstream in national and local development planning. Public and private finance have supported the implementation of the climate actions. However, most funding is still used for mitigation. Adaptation finance needs support, especially in agriculture. This research paper studies opportunities for microfinance to play a role together with existing resources in supporting climate change adaptation in Indonesia. The data was acquired and analysed through a literature review, analysis of case studies and interviews with stakeholders in the climate change-related financial sector. The central findings regarding the opportunity for microfinance to contribute to the existing schemes in Indonesian climate change adaptation finance for agriculture are worthy of the result. This study found that adaptation finance is mostly used for indirect activities. Meanwhile, local communities, and farmers in particular, need directly targeted measures to adapt to climate change. An alternative approach is providing microfinance, insurance and capacity development for farmers to produce high quality agricultural products. This would contribute to optimizing the agri-food value chain, which supports socio-economic development of stakeholders, especially farmers. Hence, microfinance appears to be one potential solution to support direct climate change adaptation actions for the agricultural sector. However, this may not be strong enough to finance the entire needs for agricultural climate actions. Adaptation is contextual, so it has to be grounded in the needs of local communities. Microfinance needs public sectors support as well as other resources from the private sector. In the case of rapid response to disasters, which often destroy the agricultural sector, microfinance should be advantageous in supporting adaptation. However, in reality, it does not work, as it is prevented by regulations. So, this can be an area the public sector can support as a risk-taker as well as by providing initial funds and resources for scaling up efforts.
Resumo:
The high cost of maize in Kenya is basically driven by East African regional commodity demand forces and agricultural drought. The production of maize, which is a common staple food in Kenya, is greatly affected by agricultural drought. However, calculations of drought risk and impact on maize production in Kenya is limited by the scarcity of reliable rainfall data. The objective of this study was to apply a novel hyperspectral remote sensing method to modelling temporal fluctuations of maize production and prices in five markets in Kenya. SPOT-VEGETATION NDVI time series were corrected for seasonal effects by computing the standardized NDVI anomalies. The maize residual price time series was further related to the NDVI seasonal anomalies using a multiple linear regression modelling approach. The result shows a moderately strong positive relationship (0.67) between residual price series and global maize prices. Maize prices were high during drought periods (i.e. negative NDVI anomalies) and low during wet seasons (i.e. positive NDVI anomalies). This study concludes that NDVI is a good index for monitoring the evolution of maize prices and food security emergency planning in Kenya. To obtain a very strong correlation for the relationship between the wholesale maize price and the global maize price, future research could consider adding other price-driving factors into the regression models.
Resumo:
Water and food are fundamental human rights. However, a number of communities in the world suffer due to a lack of these most basic needs. With few alternative economic opportunities, communities in rural and mountainous Kyrgyzstan have to rely mainly on agriculture for their livelihoods.
Resumo:
With the global population projected to reach 9 billion in 2050, demand for food is expected to increase by over 50% in 2030 and 70% in 2050 (UN-Water, 2013). Already agriculture is the largest user of water with irrigation accounting for nearly 70% of all freshwater withdrawals (UN-Water, 2016).
Resumo:
In the rural areas of Brazil, a farmer runs his agricultural empire with a fierce hand: he exploits his workers and the land to their limits. Lack of sustainable land management leads to the pollution of rivers, changes in rain patterns, and exhaustion of the soil.
Resumo:
This paper is an analysis of emic versus etic approaches to climate change resiliency, taking as a case study the traditional ceremony performed by farmers in eastern Flores, Indonesia to rid their fields of rats. This paper begins by providing a theoretical framework discussion on the dominant etic and emic academic research on monsoons and climate change impacts on agriculture. The rat ceremony performed in villages throughout East Flores is a local custom used to rid agricultural fields of pests—often rats—that come from the surrounding forests to feed on the agricultural crops when the rains become erratic. This paper argues that analyzing the rat ceremony through an emic lens allows for better future resiliency to monsoon shifts due to climate change. It is argued that the rat ceremony demonstrates a way in which community resiliency is strengthened by an adaptive approach that supports an already existing community ceremony that emphasizes two essential tenets: community solidarity and coexistence with nature. Both tenets directly promote community resiliency. An explicit emphasis on emic approaches to climate change challenges could help re-define how resiliency is understood and supported within vulnerable communities such as rural villages.
Resumo:
Beef production can be environmentally detrimental due in large part to associated enteric methane (CH4) production, which contributes to climate change. However, beef production in well-managed grazing systems can aid in soil carbon sequestration (SCS), which is often ignored when assessing beef production impacts on climate change. To estimate the carbon footprint and climate change mitigation potential of upper Midwest grass-finished beef production systems, we conducted a partial life cycle assessment (LCA) comparing two grazing management strategies: 1) a non-irrigated, lightly-stocked (1.0 AU/ha), high-density (100,000 kg LW/ha) system (MOB) and 2) an irrigated, heavily-stocked (2.5 AU/ha), low-density (30,000 kg LW/ha) system (IRG). In each system, April-born steers were weaned in November, winter-backgrounded for 6 months and grazed until their endpoint the following November, with average slaughter age of 19 months and a 295 kg hot carcass weight. As the basis for the LCA, we used two years of data from Lake City Research Center, Lake City, MI. We included greenhouse gas (GHG) emissions associated with enteric CH4, soil N2O and CH4 fluxes, alfalfa and mineral supplementation, and farm energy use. We also generated results from the LCA using the enteric emissions equations of the Intergovernmental Panel on Climate Change (IPCC). We evaluated a range of potential rates of soil carbon (C) loss or gain of up to 3 Mg C ha-1 yr-1. Enteric CH4 had the largest impact on total emissions, but this varied by grazing system. Enteric CH4 composed 62 and 66% of emissions for IRG and MOB, respectively, on a land basis. Both MOB and IRG were net GHG sources when SCS was not considered. Our partial LCA indicated that when SCS potential was included, each grazing strategy could be an overall sink. Sensitivity analyses indicated that soil in the MOB and IRG systems would need to sequester 1 and 2 Mg C ha-1 yr-1 for a net zero GHG footprint, respectively. IPCC model estimates for enteric CH4 were similar to field estimates for the MOB system, but were higher for the IRG system, suggesting that 0.62 Mg C ha-1 yr-1 greater SCS would be needed to offset the animal emissions in this case.
Resumo:
In this paper, we propose climate adaptation solutions for the green sectors in three different zones of MENA: Egypt’s Delta (irrigated), Karak, in the highlands of Jordan (rainfed), and Lebanon’s Orontes basin (mixed: rainfed-irrigated). We analysed land use and crop intensification, and calculated the economic productivity of water – a critical scarce resource in MENA. By integrating the results with evidence from literature on the potential impacts of climate change and socio-economic factors, we could identify vulnerability levels of the three regions and propose adaptation measures relying of the concept of the “food-water-energy nexus.” While the vulnerability levels are found to be high in the Delta (Egypt) and Karak (Jordan), mainly due to water scarcity and poor adaptive capacity, the vulnerability level is moderate in the Orontes zone (Lebanon) due to a diversified agricultural sector and good market development, coupled with moderate water scarcity. Proposed adaptation solutions range from measures to improve technical efficiency, to measures that encourage economically efficient allocation by use of market forces. For both cases, the development of market opportunities is emphasized to make the proposed measures attractive to farmers.
Resumo:
The aims of this thesis were to determine the animal health status in organic dairy farms in Europe and to identify drivers for improving the current situation by means of a systemic approach. Prevalences of production diseases were determined in 192 herds in Germany, France, Spain, and Sweden (Paper I), and stakeholder consultations were performed to investigate potential drivers to improve animal health on the sector level (ibid.). Interactions between farm variables were assessed through impact analysis and evaluated to identify general system behaviour and classify components according to their outgoing and incoming impacts (Paper II-III). The mean values and variances of prevalences indicate that the common rules of organic dairy farming in Europe do not result in consistently low levels of production diseases. Stakeholders deemed it necessary to improve the current status and were generally in favour of establishing thresholds for the prevalence of production diseases in organic dairy herds as well as taking actions to improve farms below that threshold. In order to close the gap between the organic principle of health and the organic farming practice, there is the need to formulate a common objective of good animal health and to install instruments to ensure and prove that the aim is followed by all dairy farmers in Europe who sell their products under the organic label. Regular monitoring and evaluation of herd health performance based on reference values are considered preconditions for identifying farms not reaching the target and thus in need of improvement. Graph-based impact analysis was shown to be a suitable method for modeling and evaluating the manifold interactions between farm factors and for identifying the most influential components on the farm level taking into account direct and indirect impacts as well as impact strengths. Variables likely to affect the system as a whole, and the prevalence of production diseases in particular, varied largely between farms despite some general tendencies. This finding reflects the diversity of farm systems and underlines the importance of applying systemic approaches in health management. Reducing the complexity of farm systems and indicating farm-specific drivers, i.e. areas in a farm, where changes will have a large impact, the presented approach has the potential to complement and enrich current advisory practice and to support farmers’ decision-making in terms of animal health.
Resumo:
Forschungsgegenstand der Arbeit sind Marketingstrategien zur In-Wert-Setzung von Naturschutzmaßnahmen in der ökologischen Direktvermarktung. Vor diesem Hintergrund wurden anhand konkreter Beispiele unterschiedliche Marketingstrategien und Kommunikationskonzepte verglichen und untersucht, wodurch die Aufpreisbereitschaft der KundInnen für den Zusatznutzen „Naturschutz“ beeinflusst wird. Die Untersuchungen fanden zwischen November 2015 und Januar 2016 auf drei Höfen, die Naturschutzmaßnahmen in die ökologische Direktvermarktung integriert haben, statt. Zunächst wurden leitfadengestützte Experteninterviews mit den Betriebsleitern, bzw. den Verantwortlichen für den Naturschutz, durchgeführt. Schwerpunkt der Interviews war das Naturschutzengagement der Betriebe und die Verwendung der Marketinginstrumente. Die Auswertung erfolgte anhand der inhaltlich strukturierenden qualitativen Inhaltsanalyse. Anschließend fanden in den drei Hofläden persönlich-schriftliche Kundenbefragungen mit Hilfe standardisierter Fragebögen statt. Zur Auswertung wurden statistische Tests im Rahmen der deskriptiven und explorativen Datenanalyse mit der Statistiksoftware SPSS 22.0 vorgenommen. Ergänzt wurden die Daten durch eine Internetrecherche zu weiteren Kommunikations- und Vermarktungskonzepten. Die Ergebnisse zeigten, dass es insgesamt in Deutschland nur wenige Marketingstrategien zur In- Wert-Setzung von Naturschutzmaßnahmen in der Direktvermarktung zu geben scheint. Auf den Höfen wurden zur In-Wert-Setzung des Naturschutzes insbesondere Öko-Marketingstrategien und Zusatznutzenstrategien verfolgt. Dabei stand die Kommunikationspolitik im Vordergrund. Die Intensität, mit der der Naturschutz marketingtechnisch eingesetzt wurde, reichte von sehr gering (Vorwerk Podemus) bis zu sehr ausgeprägt (Lämmerhof). Ob die KundInnen bereit sind, einen Aufpreis für den Naturschutz zu zahlen und ob es ihnen wichtig ist, dass sich der Betrieb für den Naturschutz einsetzt, stand in einem signifikanten Zusammenhang. Auch ob die KundInnen sich über das Engagement der Betriebe in den Bereichen Arten- und Biotopschutz gut informiert fühlten, beeinflusste die Aufpreisbereitschaft. Andere Studien bestätigen eine Aufpreisbereitschaft für einen Zusatznutzen wie den Naturschutz. Die Zahlungsbereitschaft kann durch persönliche Betroffenheit erhöht werden. Die Ergebnisse legen nahe, dass die Sensibilisierung der KundInnen mit Hilfe eines systematisch geplanten und umgesetzten Kommunikationskonzeptes für die In-Wert-Setzung von Naturschutzmaßnahmen von großer Bedeutung ist. Transparenz und Glaubwürdigkeit spielen bei dem Transport des Konzeptes eine ausschlaggebende Rolle. Abschließend wurden Handlungsempfehlungen für LandwirtInnen und DirektvermarkterInnen formuliert.