The role of al-Bīrūnī in the history of hydrology. A modern vision 600 years in advance.

In today's contemporary world, a walk through the epistemology of the hydrological cycle can help us to frame many current problems in a broader framework, reminding us to remain humble. Among all the scientific concepts that are taught in schools of all kinds and levels everywhere on the planet, the water cycle is one of the concepts that remain in the head even after a long time from the end of compulsory school. The ease in remembering this theory can be attributed to its relative simplicity: water evaporates from lakes, seas and oceans; the vapor forms the clouds; from the clouds come the rains and snows that feed the glaciers and Earth's surface and underground waterways, which in turn return to the oceans, and so on. However, the mechanism is only apparently simple. The trained hydrologist knows very well that studying and communicating the complexity hidden behind hydrological science requires patience and dedication. Modern hydrology, in the Western world, can be considered born at the end of the 17th century thanks to two members of the Académie Royale des Sciences: Pierre Perrault (1611-1680) and Edme Mariotte (1620-1684). The treatises of these two scholars – De l'origine des fontaines (Perrault 1674) and Traité du mouvement des eaux et des autres corps fluides (Mariotte1686) – can be considered the first attempts to verify the actual ability of precipitation to supply rivers and sources by means of quantitative analyses. Anyway, it is clear that a modern vision of the hydrological cycle was present in the Islamic world at the time of al-Bīrūnī. Although he did not leave writings dedicated solely to hydrological sciences, al-Bīrūnī's "modern" vision of the hydrological cycle clearly emerges in some extant passages of his works. In this memoir, we will discuss how al-Bīrūnī's vision of the hydrological cycle mirrors a theoretical framework widespread among the Islamic scholars of his age, and how its fundamental concepts anticipate the modern hydrological vision that took shape in Europe in the mid-1600s

System Dynamics Applied to Terraced Agroecosystems: The Case Study of Assaragh (Anti-Atlas Mountains, Morocco)

Terraced agroecosystems (TAS)—apart from being an important cultural heritage element—are considered vital for sustainable water resource management and climate change adaptation measures. However, this traditional form of agriculture, with direct implications in food security at a local scale, has been suffering from abandonment or degradation worldwide. In light of this, the need to fully comprehend the complex linkage of their abandonment with different driving forces is essential. The identification of these dynamics makes possible an appropriate intervention with local initiatives and policies on a larger scale. Therefore, the main aim of this paper is to introduce a comprehensive multidisciplinary framework that maps the dynamics of the investigated TAS’s abandonment, by defining cause–effect relationships on a hydrogeological, cological and social level, through tools from System Dynamics studies. This methodology is implemented in the case of Assaragh TAS, a traditional oasis agroecosystem in the Moroccan Anti-Atlas, characterized by data scarcity. Through field studies, interviews, uestionnaires and freely accessible databases, the TAS’s abandonment, leading to a loss in agrobiodiversity, is linked to social rather than climatic drives. Additionally, measures that can counteract the phenomenon and strengthen the awareness of the risks associated with climate change and food security are proposed

Assessing the impact of deficit irrigation strategies on agronomic and productive parameters of Menara olive cultivar: implications for operational water management

The olive tree is an iconic tree in the Mediterranean region, traditionally cultivated under rainfed conditions; however, olive cultivars are also found outside the Mediterranean region and are widely used for oil and olive production. However, with the increasing aridity and global changes, olive agroecosystems are facing sustainability challenges. This study aims to evaluate the effect of two deficit irrigation strategies on the agronomic and productive parameters of the Menara, olive cultivar as a tool for operational irrigation water management. For this purpose, an experiment was conducted on an olive orchard for two consecutive years (2021 and 2022), comparing four regulated deficit irrigation (RDI) treatments and two sustained deficit irrigation (SDI) treatments, with fully irrigated trees. The results showed that moderate and controlled water stress under RDI did not significantly affect the yield of the Menara olive cultivar. In addition, by reducing plant water requirement by 20% during sensitive periods and by 40% during normal periods, under RDI, it is possible to save between 25% and 30% of irrigation water and to increase water productivity by 5%–20% with a slight decrease in fruit yield ranging between 10% and 15%. However, the trees subjected to the sustained deficit irrigation strategy exhibited a reduced capacity for shoot growth compared to those under RDI and fully irrigated conditions. Our findings showed that water deprivation during sensitive periods reduced phenological traits and slowed down shoot growth. Furthermore, the water status of the trees was reflected in fruit volume, as a decrease in water supply resulted in a corresponding reduction in fruit volume. Although the study provides important insights into water management strategies for olive cultivation, the short observation period does not allow for long-term plant adaptation evaluation and productivity beyond 2 years. Therefore, it is recommended that future studies extend the observation period to better understand plant adaptation to irrigation regimes

HYDRAULICS AND HYDROLOGY IN A PASSAGE OF THE KITĀB AL-ĀṮĀR AL-BĀQIYA BY AL-BĪRŪNĪ

The authors translate and comment a digression from the Kitāb al-āṯār al-bāqiya on several hydraulic and hydrological subjects. The passage reveals al-Bīrūnī’s understanding of fluvial regimes, water physical behaviour, and of a handful of peculiar natural phenomena. Al-Bīrūnī departs from a discussion of weather forecast and seasonal fluvial regimes of the Tigris, Euphrates, Oxus, and Nile. The main concern of al-Bīrūnī is to defend the principle that water moves only downwards in absence of external forces. In doing so, the Khwarazmian scientist touches on the origin of salinity of the seas, the functioning of syphons related hydraulic machines, and relates a report of an artificial phenomenon, that he dismisses as result of faulty observations, that could be recognised as a hydraulic jump. In addition, the passage contains much relevant information on al-Bīrūnī’s understanding of the inhabitability of subequatorial regions, the possibility of the void, and the water cycle

The role of al-Bīrūnī in the history of hydrology. A modern vision 600 years in advance.

<p>In today's contemporary world, a walk through the epistemology of the hydrological cycle can help us to frame many current problems in a broader framework, reminding us to remain humble. Among all the scientific concepts that are taught in schools of all kinds and levels everywhere on the planet, the water cycle is one of the concepts that remain in the head even after a long time from the end of compulsory school. The ease in remembering this theory can be attributed to its relative simplicity: water evaporates from lakes, seas and oceans; the vapor forms the clouds; from the clouds come the rains and snows that feed the glaciers and Earth's surface and underground waterways, which in turn return to the oceans, and so on. However, the mechanism is only apparently simple. The trained hydrologist knows very well that studying and communicating the complexity hidden behind hydrological science requires patience and dedication. Modern hydrology, in the Western world, can be considered born at the end of the 17th century thanks to two members of the Académie Royale des Sciences: Pierre Perrault (1611-1680) and Edme Mariotte (1620-1684). The treatises of these two scholars – <i>De l'origine des fontaines</i> (Perrault 1674) and <i>Traité du mouvement des eaux et des autres corps fluides</i> (Mariotte1686) – can be considered the first attempts to verify the actual ability of precipitation to supply rivers and sources by means of quantitative analyses.</p><p>Anyway, it is clear that a modern vision of the hydrological cycle was present in the Islamic world at the time of al-Bīrūnī. Although he did not leave writings dedicated solely to hydrological sciences, al-Bīrūnī's "modern" vision of the hydrological cycle clearly emerges in some extant passages of his works.</p><p>In this memoir, we will discuss how al-Bīrūnī's vision of the hydrological cycle mirrors a theoretical framework widespread among the Islamic scholars of his age, and how its fundamental concepts anticipate the modern hydrological vision that took shape in Europe in the mid-1600s.</p&gt

'n saccu vacanti non pò stari addritta. Un sacco vuoto non può stare in piedi. La sfida siciliana del quartiere San Giacomo ad Aidone

The spaces left empty offer opportunities for the birth and development of new cultural and social ecosystems. In analogy to the pioneer vegetation that claims its ecological niches, laying the foundations for a reconquest of nature, the artistic intervention within the abandoned urban space creates the fertile ground for the rebirth of the same fabric. The hamlet of San Giacomo, thanks mainly to spontaneous artistic interventions almost replacing those promoted by the administration, is finally experiencing a slow revaluation that is also expressed in a series of projects for the revitalization of the area

Sul significato culturale delle tecniche irrigue tradizionali in scarsità idrica

Le tecniche irrigue tradizionali sono uno degli assi portanti delle oasi e un presidio nella lotta contro la desertificazione. La loro importanza trascende l’essere una mera eredità storica, perché hanno innervato le società tradizionali di tutta l’area mediterranea e dell’Asia centrale. Si propone con questo lavoro una riflessione su loro significato culturale, attualità e futuro, come punto di partenza per una rilettura dell’importanza dell’agricoltura nella protezione e conservazione del suolo, e della sua possibile relazione con la pianificazione territoriale. // Traditional irrigation techniques are an axle for oases and a defence method against desertification. Their importance goes beyond the mere historical heritage, in fact they innervated traditional societies of the whole Mediterranean basin and central Asia. With this paper we propose a reflection upon their cultural meaning, their current and future state as a starting point for a reanalysis of the importance of agriculture in soil protection, and of its possible relationship with land planning

Short-Term Responses of Aquatic Ecosystem and Macroinvertebrate Assemblages to Rehabilitation Actions in Martil River (North-Western Morocco)

This study aimed to evaluate the effects of the Martil River rehabilitation project and recently constructed dam infrastructures to reduce flood risks and to promote local socio-economic development on the ecological integrity of the river. The assessment focused on changes in fluvial landforms over time and the evaluation of aquatic ecosystems based on six physicochemical parameters (temperature, pH, electrical conductivity, dissolved oxygen, biochemical oxygen demand, and chemical oxygen demand), morpho-hydrological variables (stream width, water depth, and current speed), habitat indices (QBR, IHF, and MQI), and macroinvertebrate assemblages of EPT, OCH, and Chironomidae (Diptera) at five stations from autumn 2015 to spring 2018 (prior to and during the rehabilitation actions). The results showed that the river rehabilitation project led to profound changes in Martil River’s ecosystem and water quality over time. Physicochemical and habitat measurements at the rehabilitated sites revealed a major change in macroinvertebrate communities due to changes in fluvial landforms in relation to flow-sediment regimes. As a result, some typical species of lentic habitats disappeared, while alien, opportunistic, and lotic species appeared

Pollen Variability of <i>Alnus glutinosa</i> (L.) Gaerth. (Betulaceae) from Southern Range Edge Populations in Northern Morocco

Moroccan populations of Alnus glutinosa (L.) Gaerth. (Betulaceae) are found at the southern limit of the species’ range and are represented by tetraploid cytotypes with no available pollen data. The objective of this study was to assess the morphological and morphometric variability of the pollen, specifically focusing on pollen diameters and the number of apertures. To achieve this, we sampled 11 populations that are representative of the Moroccan distribution area of this species. We employed a hierarchical sampling design (11 populations, 10 trees per population, and from 30 to 300 pollen grains per tree, depending on the character measured) to examine different levels of variability: interpopulation, intrapopulation, and intraindividual. The results demonstrate that there is no discernible difference in the morphology or size of the pollen among the Moroccan tetraploid populations. However, we observed a high degree of intraspecific variability in pollen morphometric traits, but most of this variability is associated with the intraindividual level