Sustainability of high-density olive orchards: Hints for irrigation management and agroecological approaches

The production of olive oil in Portugal and other countries of the Mediterranean region has greatly increased in recent years. Intensification efforts have focused on the growth of the planted area, but also on the increase of the orchards density and the implementation of irrigation systems. Concerns about possible negative impacts of modern olive orchard production have arisen in the last years, questioning the trade-offs between the production benefits and the environmental costs. Therefore, it is of great importance to review the research progress made regarding agronomic options that preserve ecosystem services in high-density irrigated olive orchards. In this literature review, a keywords-based search of academic databases was performed using, as primary keywords, irrigated olive orchards, high density/intensive/hedgerow olive orchards/groves, irrigation strategies, and soil management. Aside from 42 general databases, disseminated research, and concept-framing publications, 112 specific studies were retrieved. The olive orchards were classified as either traditional (TD) (50–200 trees ha−1), medium-density (MD) (201–400 trees ha−1), high-density (HD) (401–1500 trees ha−1), or super-high-density (SHD) orchards (1501–2500 trees ha−1). For olive crops, the crop coefficient (Kc) ranges ranges from 0.65 to 0.70, and can fall as low as 0.45 in the summer without a significant decrease in oil productivity. Several studies have reported that intermediate irrigation levels linked with the adoption of deficit irrigation strategies, like regulated deficit irrigation (RDI) or partial rootzone drying (PRD), can be effective options. With irrigation, it is possible to implement agroecosystems with cover crops, non-tillage, and recycling of pruning residues. These practices reduce the soil erosion and nutrient leaching and improve the soil organic carbon by 2 to 3 t C ha−1 year−1. In this situation, in general, the biodiversity of plants and animals also increases. We expect that this work will provide a reference for research works and resource planning focused on the improvement of the productive and environmental performance of dense irrigated olive orchards, thereby contributing to the overall enhancement of the sustainability of these expanding agroecosystems

Hints for Irrigation Management and Agroecological Approaches

Publisher Copyright: © 2023 by the authors.The production of olive oil in Portugal and other countries of the Mediterranean region has greatly increased in recent years. Intensification efforts have focused on the growth of the planted area, but also on the increase of the orchards density and the implementation of irrigation systems. Concerns about possible negative impacts of modern olive orchard production have arisen in the last years, questioning the trade-offs between the production benefits and the environmental costs. Therefore, it is of great importance to review the research progress made regarding agronomic options that preserve ecosystem services in high-density irrigated olive orchards. In this literature review, a keywords-based search of academic databases was performed using, as primary keywords, irrigated olive orchards, high density/intensive/hedgerow olive orchards/groves, irrigation strategies, and soil management. Aside from 42 general databases, disseminated research, and concept-framing publications, 112 specific studies were retrieved. The olive orchards were classified as either traditional (TD) (50–200 trees ha−1), medium-density (MD) (201–400 trees ha−1), high-density (HD) (401–1500 trees ha−1), or super-high-density (SHD) orchards (1501–2500 trees ha−1). For olive crops, the crop coefficient (Kc) ranges ranges from 0.65 to 0.70, and can fall as low as 0.45 in the summer without a significant decrease in oil productivity. Several studies have reported that intermediate irrigation levels linked with the adoption of deficit irrigation strategies, like regulated deficit irrigation (RDI) or partial rootzone drying (PRD), can be effective options. With irrigation, it is possible to implement agroecosystems with cover crops, non-tillage, and recycling of pruning residues. These practices reduce the soil erosion and nutrient leaching and improve the soil organic carbon by 2 to 3 t C ha−1 year−1. In this situation, in general, the biodiversity of plants and animals also increases. We expect that this work will provide a reference for research works and resource planning focused on the improvement of the productive and environmental performance of dense irrigated olive orchards, thereby contributing to the overall enhancement of the sustainability of these expanding agroecosystems.publishersversionpublishe

Olive growing – The challenge of sustainability

A biodiversidade tem um papel preponderante no fornecimento de importantíssimos serviços do ecossistema. No olival, para além dos serviços de produção (produção de azeitona e azeite), existem serviços de regulação (manutenção de habitats, controlo de pragas e doenças), serviços de suporte (formação de solo e ciclos dos nutrientes) e ainda serviços de recreio (turismo, recreação e cultura). Este trabalho tem como principais objetivos identificar e divulgar boas práticas que promovam os serviços dos ecossistemas olivícolas. O desafio que o setor oleícola tem neste momento de garantir a sua sustentabilidade passa muito pela conservação e fomento da biodiversidade neste ecossistema. A preservação e promoção dos serviços disponibilizados por este agroecossistema é um contributo importante para a sustentabilidade do território

Patologia e clínica das espécies pecuárias

O presente trabalho teve como objetivo a descrição das atividades desenvolvidas durante o estágio curricular no âmbito do Mestrado Integrado em Medicina Veterinária pela Universidade de Évora. Numa primeira parte é apresentada a casuística acompanhada ao longo do estágio, com referência pormenorizada a alguns casos clínicos, nas diversas áreas de intervenção da clínica em espécies pecuárias. A segunda parte deste relatório é composta por uma breve revisão bibliográfica sobre o tema “urolitíase em ruminantes”. Na terceira e última parte serão apresentados três casos clínicos acompanhados no decorrer do estágio. Será feita uma discussão onde são relatados os procedimentos cirúrgicos e terapêuticas médicas efetuadas com a devida crítica e possíveis melhorias; Pathology and Clinic of Livestock Species Abstract: The present report aims to describe the activities developed during the curricular traineeship as part of the Integrated Master’s Degree in Veterinary Medicine, in Évora University. The first part includes the casuistry that took place along the externship, giving emphasis to some of the clinical cases assessed in different livestock species clinical areas. The second part of this report consists of a brief literature review on the topic "urolithiasis in ruminants". In the third and final part, three clinical cases followed during the externship will be approached and described. A discussion will be made where the surgical procedures and medical therapies performed are reported, with due criticism and possible improvements

An overview on the use of enhanced efficiency nitrogen fertilizers in irrigated Mediterranean agriculture

In Mediterranean regions climate change has led to greater inter and intra-annual rainfall irregularity, causing an increase in the demand for irrigation water, inevitably accompanied by an increase in the use of others resources like nitrogen fertilizers. Nitrogen is associated with negative economic and environmental impacts, which requires particularly important decision-making in terms of its application to meet crop needs. The agronomic efficiencies of water and nitrogen vary widely among different environments and can be modified due to management practices. However, some studies suggest that agronomic practices alone are not sufficient to entirely avoid nitrogen losses. In irrigated cropping systems, where classical nitrogen fertilizers are partially applied through irrigation water, Enhanced Efficiency Fertilizers (EEF), namely slow release and controlled release products, and nitrification inhibitors, have the potential to reduce nitrogen losses, contributing to higher resource-use efficiencies. This work aims to provide an overview of the possibilities of successfully using this type of fertilizers in irrigated agriculture, especially in Mediterranean climate regions, and the need for research in this field

Ainda a rega dos cereais de sementeira outono-invernal: análise dos dois últimos anos agrícolas

Nas culturas com sementeira outono-invernal, nomeadamente nos cereais praganosos como a cevada e o trigo, o fornecimento de água através da rega pode ser decisivo para a obtenção de elevadas produtividades e para potenciar a qualidade industrial do grão. Todavia, a importância da rega e, consequentemente, o volume de água aplicado, variam de acordo com o volume da precipitação que ocorre durante o ciclo cultural e, especialmente,com a sua distribuição neste período

Water regime and nitrogen management to cope with wheat yield variability under the mediterranean conditions of Southern Portugal

POCI-01-0145-FEDER-023262 LISBOA-01-0145-FEDER-023262 SAICT-POL/23262/2016Global climate change accentuates the seasonal and interannual irregularity of temperature and precipitation of the Mediterranean climate. The consequences of this variability on wheat production are felt on its development cycle and productivity, making the production chain of this crop vulnerable to the occurrence of years with abnormal distributions of precipitation and with extreme temperatures. Adaptation strategies like irrigation or fertilization can help to cope with the negative impacts of climate uncertainty. This study evaluated the effects of water regime and nitrogen (N) fertilization techniques on wheat production in southern Portugal based on the results of three trials conducted in two agricultural years (2016/2017 and 2017/2018) with contrasting climate conditions. Phenology and yield were evaluated by comparing water regimes (R1, full irrigation; R2, supplemental irrigation at four stages: start of stem extension, booting, anthesis, grain filling; R0, rainfed (in 2017/2018)) and N fertilization splitting/timing and type (conventional and enhanced efficiency fertilizers (EEFs): controlled-release N, stabilized with nitrification inhibitor, and stabilized with urease inhibitor). Significant effects of water regime on grain yield were obtained in 2016/2017, a year with extreme aridity and high water requirements felt from the tillering stage, in the trial with conventional fertilizers. In 2017/2018, when a beneficial seasonal rainfall distribution occurred, water regime did not influence grain yield, pointing to the feasibility of supplementary irrigation to maximize water productivity. Nitrogen fertilization influenced yield and its components, with the highest values of grain yield being obtained with conventional fertilizer. Regardless of the possible effects on grain quality, the use of EEF did not prove to have an indisputable effect on wheat yield in the conditions under which the trials were conducted. Comparison of the results in the two years accentuates the need to continue the evaluation of the influence of agronomic management in wheat production in the context of adaptation to the climatic uncertainty in Mediterranean regions.publishersversionpublishe

Digitization of crop nitrogen modelling: A review

Applying the correct dose of nitrogen (N) fertilizer to crops is extremely important. The current predictive models of yield and soil–crop dynamics during the crop growing season currently combine information about soil, climate, crops, and agricultural practices to predict the N needs of plants and optimize its application. Recent advances in remote sensing technology have also contributed to digital modelling of crop N requirements. These sensors provide detailed data, allowing for real-time adjustments in order to increase nutrient application accuracy. Combining these with other tools such as geographic information systems, data analysis, and their integration in modelling with experimental approaches in techniques such as machine learning (ML) and artificial intelligence, it is possible to develop digital twins for complex agricultural systems. Creating digital twins from the physical field can simulate the impact of different events and actions. In this article, we review the state-of-the-art of modelling N needs by crops, starting by exploring N dynamics in the soil−plant system; we demonstrate different classical approaches to modelling these dynamics so as to predict the needs and to define the optimal fertilization doses of this nutrient. Therefore, this article reviews the currently available information from Google Scholar and ScienceDirect, using relevant studies on N dynamics in agricultural systems, different modelling approaches used to simulate crop growth and N dynamics, and the application of digital tools and technologies for modelling proposed crops. The cited articles were selected following the exclusion criteria, resulting in a total of 66 articles. Finally, we present digital tools and technologies that increase the accuracy of model estimates and improve the simulation and presentation of estimated results to the manager in order to facilitate decision-making processes

Combined effects of irrigation management and nitrogen fertilization on soft wheat productive responses under Mediterranean conditions

Wheat yield responses to water and nitrogen vary widely among different environments and they can be shifted due to technological, environmental, or economic factors. In regions with a Mediterranean-type climate, the balance between the key climate variables and the most critical stages of wheat grow implies that the success of the crop depends to a very large degree on the knowledge of proper water management combined with suitable fertilization strategies. For this purpose, we studied the productive responses of soft wheat to the interactive effects of irrigation and nitrogen (N) fertilization. Two trials were carried out during 2016/2017 in Beja (Southern Portugal). In both experiments, wheat responses were assessed under two water supply regimes: D1 (100% of full irrigation throughout the cycle) and D2 (100% of full irrigation at four stages: stem extension; booting; heading; grain filling). In the first trial, 165 kg of slow-release and stabilized N fertilizers were applied through 6 splitting treatments, five of them (A1 to A5) with a slow-release N fertilizer (A1 – 100% at sowing; A2 – 50% at sowing and 50% at booting; A3 - 50% at sowing, and 25% at stem extension and at heading; A4 – 75% at sowing and 25% at booting; A5 - 75% at sowing and 25% at stem extension) and another one (A6) with a stabilized N fertilizer 100% applied at sowing. In the second trial, 165 kg of conventional N fertilizer was applied through 5 splitting treatments (A1 – 33% at sowing, at tillering and at stem extension; A2 – 25% at sowing, at tillering, at stem extension and at heading; A3 - 25% at sowing, at tillering, at stem extension and at booting; A4 – 50% at tillering and 25% at booting and at heading; A5 - 50% at sowing and 25% at stem extension and at booting). In the first trial, only the number of heads per square meter showed significant influence of the irrigation regime, the highest values being registered in the D1 treatment. In the trial with conventional fertilizer, significantly higher yields and weights of 1000 grains were obtained in the D1 irrigation treatment. Significant effects of split N fertilizer application occurred only in the first trial: yield was higher in the A5 treatment, showing that early N applications with this type of fertilizers do not compromise N availability throughout the wheat grow cycle and therefore the grain production; grain protein content was higher in the A2 treatment, indicating the importance of N availability at the booting stage in order to obtain grains with desirable quality traits

Efficient use of water and nutrients in irrigated cropping systems in the Alqueva region

In the region of Alentejo, Southern Portugal, as a consequence of the implementation of the Alqueva global irrigation system, agriculture intensification is challenging the sustainability of the farming systems. The demand for water and for fertilizers is increasing but so is the demand for water use efficiency (WUE) and for nutrient use efficiency (NUE). Increasing resource-use efficiency while reducing yield gaps can be addressed by suitable agricultural management practices, as in the case of crop rotations. Based on a demonstration project carried out in two farms located in Baixo Alentejo, within the Alqueva irrigation network, soil fertility parameters, WUE and NUE (for nitrogen, phosphorus and potassium) were studied in three maize-based cropping systems: a maize monoculture (M-M) and two rotations, barley+maize-barley (BM-B) and sunflower-barley+maize (S-BM). The total soil organic matter content increased in the two rotations, an important observation especially in soils with low organic content. The final balance of extractable phosphorus and potassium was positive in the BM-B rotation. Water use efficiency values point to a less balanced performance of the S-BM rotation. The WUE and the nitrogen NUE in the different crops and rotations followed a similar pattern. The M-M and BM-B crop successions showed the best indicators of NUE for nitrogen and phosphorus. In all the cropping systems, the potassium NUE was low, suggesting the need to carefully equate the additions of this nutrient by fertilization