Salt removing species. Phytoremediation technique for Uzbekistan

Dissertação de Mestrado, Gestão da Água e da Costa, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2007As tecnicas convencionais para o controlo da salinidade do solo, nomeadamente a lixiviação do solo e o aumento da fertilização, são métodos usados para diminuir a salinidade do solo e aumentar a tolerância das culturas que se desenvolvem em solos salinos. Contudo, o uso intensivo destas tecnicas tem chamado a atenção pública para o problema da contaminação ambiental devido à salinização de camadas mais profundas do solo e dos aquíferos. Recentemente surgiu uma nova tecnica limpa e amientalmente útil, em que espécies removedoras de sal (iões) são plantadas ou semeadas nos solos salinos e têm sido utilizadas para remover o sal dos solos. A capacidade de remoção de sal de Portulaca oleracea Golden Purslane e sete plantas natives locais - Tamarix hispida, Apocynum lancifolium, Glycyrrhiza glabra, Portulaca oleracea Green Purslane, Alhagi pseudalhagi, Karelinia caspia, e Chenopodium album foram testadas neste estudo. Os ensaios de campo foram efectuados na região Khoresm, no norte do Uzbequistão, durante o Verão, o período mais sensível para os solos salinos. . A Portulaca oleracea golden purslane foi semeada em dois solos salinos diferentes, um deles regado e o outro de sequeiro. A colheita foi realizada duas vezes, ao longo da fase de crescimento e na da fase de frutificação da . Portulaca oleracea golden purslane. Os resultados mostraram que a cultura de sequeiro removeu uma quantidade mais alta de sais e a sua produção foi superior. Isto deve-se à ascensão da água capilar, que resultou numa contribuição significativa para as necessidades hídricas das plantas, aumentando a sua transpiração. A maxima remoção de sal variou de 496.6 a 511.3 kg ha-1 na fase de crescimento e na fase de frutificação da Portulaca oleracea, que eventualmente removeu cerca de 16.8 % do total de sais no solo, a 10 cm de profundidade. A mais eficiente planta nativa na remoção de sal foi a C.album. Esta planta removeu 538.4 a 596.6 kg ha-1 na fase de crescimento e na fase de frutificação, a uma profundidade de 25 cm, respectivamente, Este estudo mostrou que a Portulaca oleracea golden purslane (maior quantdade de sais) e a Chenpodium album (extracção mais profunda de sais) podem vir a ser potenciais espécies usadas para controlar e combater a salinidade nas regiões do norte do Uzbequistão e poderão também vir a ser integradas nos programas de cultivo e de rotação na para a remediação dos solos salinos.Conventional techniques, namely soil leaching and the use of enhancing fertilization are methods used to mitigate soil salinity and to increase the salt tolerance of agricultural crops grown in salt-affected soils. However, the intensive use of these techniques has also attracted public attention due to the environmental pollution caused and the contamination of groundwater resources. Recently, a new environmentally safe and clean remediation technique, whereby salt (ion) removing species are planted in the salt-affected soils, has been introduced to address salinity problems. The salt removal potential of Portulaca oleracea Golden Purslane and seven native naturally grown wild plants - Tamarix hispida, Apocynum lancifolium, Glycyrrhiza glabra, Portulaca oleracea Green Purslane, Alhagi pseudalhagi, Karelinia caspia, and Chenopodium album have been evaluated under this study. The field experiments were carried out in the Khorezm Region, in the northwest of Uzbekistan, during the summer, the most sensitive period for salt-affected soils. Portulaca oleracea golden purslane was planted in two different salt-affected soils, one field with irrigation and one without irrigation. The harvest was twice, in the developing and seedling stages of Portulaca oleracea golden purslane. The results have revealed that no irrigation was required to remove the highest soil salts and to obtain the highest biomass in Portulaca oleracea golden purslane. The capillary rise from groundwater played a significant role in meeting the demand of plants for water, increasing plant transpiration. The highest salt accumulation varied from 496.6 up to 511.3 kg ha-1 in the developing and seedling phases of Portulaca oleracea, which eventually, removed about 16.8 % of the total soil salts, at a depth of 10 cm. The most efficient wild plant in removing salts from the soil was C.album. This plant removed 538.4 up to 596.6 kg ha-1 at a depth of 25 cm, in the developing and seedling stages, respectively. The study indicated that Portulaca oleracea golden purslane (higher amount of salts) and Chenopodium album (deeper salts extraction) could become potential species used to control and to combat salinity in the northern part of Uzbekistan and could also be integrated into cultivation/rotation programmes to remediate saline soils

Impact of agricultural land use in Central Asia: a review

International audienceAbstractAgriculture is major sector in the economy of Central Asia. The sustainable use of agricultural land is therefore essential to economic growth, human well-being, social equity, and ecosystem services. However, salinization, erosion, and desertification cause severe land degradation which, in turn, degrade human health and ecosystem services. Here, we review the impact of agricultural land use in the five countries of Central Asia, Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan, during 2008–2013 in 362 articles. We use the Land Use Functions framework to analyze the type and relative shares of environmental, economic, and social topics related to agricultural land use. Our major findings are (1) research on land use in Central Asia received high levels of international attention and the trend in the number of publications exceeded the global average. (2) The impacts of land use on abiotic environmental resources were the most explored. (3) Little research is available about how agricultural land use affects biotic resources. (4) Relationships between land degradation, e.g., salinization and dust storms, and human health were the least explored. (5) The literature is dominated by indirect methods of data analysis, such as remote sensing and mathematical modeling, and in situ data collection makes up only a small proportion

Impacts of climate change adaptation options on soil functions: A review of European case‐studies

Soils are vital for supporting food security and other ecosystem services. Climate change can affect soil functions both directly and indirectly. Direct effects include temperature, precipitation, and moisture regime changes. Indirect effects include those that are induced by adaptations such as irrigation, crop rotation changes, and tillage practices. Although extensive knowledge is available on the direct effects, an understanding of the indirect effects of agricultural adaptation options is less complete. A review of 20 agricultural adaptation case‐studies across Europe was conducted to assess implications to soil threats and soil functions and the link to the Sustainable Development Goals (SDGs). The major findings are as follows: (a) adaptation options reflect local conditions; (b) reduced soil erosion threats and increased soil organic carbon are expected, although compaction may increase in some areas; (c) most adaptation options are anticipated to improve the soil functions of food and biomass production, soil organic carbon storage, and storing, filtering, transforming, and recycling capacities, whereas possible implications for soil biodiversity are largely unknown; and (d) the linkage between soil functions and the SDGs implies improvements to SDG 2 (achieving food security and promoting sustainable agriculture) and SDG 13 (taking action on climate change), whereas the relationship to SDG 15 (using terrestrial ecosystems sustainably) is largely unknown. The conclusion is drawn that agricultural adaptation options, even when focused on increasing yields, have the potential to outweigh the negative direct effects of climate change on soil degradation in many European regions

Comparative Analysis of Nature-Related Transactions and Governance Structures in Pasture Use and Irrigation Water in Central Asia

Central Asian countries have experienced a transition from a centralized state-managed economy to a decentralized market-oriented one, and gained valuable experience in designing institutions involving common-pool resource (CPR) management. Top-down policy interventions have affected natural resource usage practices and had environmental, social and economic consequences. On the other hand, in a bottom-up transformation process, many informal practices for using local resources and many forms of cooperation have emerged and become institutionalized, adapting to the changing socio-economic context. This paper demonstrates an empirical application of the Institutions of Sustainability (IoS) framework, analyzing these emerged institutions, and governance structures in pasture and irrigation management. It studies how the physical nature-related transactions are institutionalized through the operationalization of a discriminative alignment principle. The research results show that actors’ interdependencies caused by the attributes of nature-related transactions play a decisive role in institutional development in CPR management in Central Asia. The authors argue that differences in the properties of physical nature-related transactions in pasture and irrigation water use can be linked and explained through differences in the key characteristics of governance structures.Peer Reviewe

Impacts of climate change adaptation pathways in agriculture on soil services and Sustainable Development Goals - The MACSUR regional case studies

Soil systems are fundamental for food security and for sustainable development: provides biomass for food, feed, energy and fibre ; serves as habitats for organisms and gene pools (biodiversity); contributes to carbon sequestration - Effects of climate change associated with extreme events, such as heavy rainfall, heat waves, drought and landslides, however, threatens to increase the potential for soil erosion and soil compaction ; Climate change may affect soil functions and services in two ways, directly and indirectly: e.g. soil erosion rates may increase because of increased frequencies of high intensity rainfalls → direct; irrigation regimes, crop rotation changes, or soil tillage practices as adaptation measures may improve or deteriorate soil quality → indirect - Comprehensive evidence exists for the first case of direct effects, knowledge about the indirect effects of agricultural adaptation pathways is more scattered - Meanwhile, improving soil functions play an important role in achieving a number of Sustainable Development Goals (SDGs), particularly (Montanarella & Alva 2015; Bouma & Montanarella 2016): SDG 2: achieve food security and promote sustainable agriculture; SDG 13: take action to combat climate change and its impacts; SDG 15: reverse land degradation and halt biodiversity loss ; CONCLUSIONS: While comprehensive evidence exists for direct effect of climate change on soil services, there has yet to be a study that has investigated the indirect linkage; This study seeks to address this gap so as to improve the scientific knowledge on sustainable soil management; Although adaptation practices show improvements in soil erosion and soil organic matters, the main challenge remains to combat soil compaction; Adaptation practices reveal rather positive effect on food and biomass production as well as improvement of carbon sequestration in soil (storing more carbon in soils) but other two functions seem to be less focus; Achievement of SDG 2 and 13 targets are currently underway with positive link, however the achievement of SDG 15 need to be the focus going forward; We hope to get completed information from all case studies to improve the robustness of the findings; We feel rather biased approach towards the northern part of Europe (N=7); The study aimed to understand and find out the impacts of climate change adaptation practices on soil services. Appropriate “response” policy tools could be an additional interesting research; How climate change impacts soil function in the absence of adaptation → perhaps, would reveal the value of adaptation knowledge and actio

Imapcts of climate change adaptation pathways in agriculture on soil services and Sustainable Development Goals

Soil systems are fundamental for food security and for sustainable developmentprovides biomass for food, feed, energy and fibreserves as habitats for organisms and gene pools (biodiversity)contributes to carbon sequestration•Effects of climate change associated with extreme events, such as heavy rainfall, heat waves, drought and landslides, however, threatens to increase the potential for soil erosion and soil compactionClimate change may affect soil functions and services in two ways, directly and indirectlye.g. soil erosion rates may increase because of increased frequencies of high intensity rainfalls → directirrigation regimes, crop rotation changes, or soil tillage practices as adaptation measures may improve or deteriorate soil quality → indirect•Comprehensive evidence exists for the first case of direct effects, knowledge about the indirect effects of agricultural adaptation pathways is more scattered•Meanwhile, improving soil functions play an important role in achieving a number of Sustainable Development Goals (SDGs), particularly (Montanarella & Alva 2015; Bouma & Montanarella 2016):SDG 2: achieve food security and promote sustainable agricultureSDG 13: take action to combat climate change and its impactsSDG 15: reverse land degradation and halt biodiversity loss ConclusionsWhile comprehensive evidence exists for direct effect of climate change on soil services, there has yet to be a study that has investigated the indirect linkage•This study seeks to address this gap so as to improve the scientific knowledge on sustainable soil management•Although adaptation practices show improvements in soil erosion and soil organic matters, the main challenge remains to combat soil compaction•Adaptation practices reveal rather positive effect on food and biomass production as well as improvement of carbon sequestration in soil (storing more carbon in soils) but other two functions seem to be less focus•Achievement of SDG 2 and 13 targets are currently underway with positive link, however the achievement of SDG 15 need to be the focus going forward•We hope to get completed information from all case studies to improve the robustness of the findings•We feel rather biased approach towards the northern part of Europe (N=7)•The study aimed to understand and find out the impacts of climate change adaptation practices on soil services. Appropriate “response” policy tools could be an additional interesting research•How climate change impacts soil function in the absence of adaptation → perhaps, would reveal the value of adaptation knowledge and action

Sustainability Considerations in Water–Energy–Food Nexus Research in Irrigated Agriculture

Irrigated agriculture is essential to satisfying the globally increasing demand for food and bio-based products. Yet, in water scarce regions, water-use for irrigation aggravates the competition for the use of water for other purposes, such as energy production, drinking water and sanitation. Solutions for sustainable food production through irrigated agriculture require a systemic approach to assess benefits and trade-offs across sectors. Here, the water–energy–food (WEF) nexus has become an important concept in natural resource management. It has been conceptualized to analyze linkages and trade-offs between the three sectors, across temporal and spatial scales. However, the concept has so far mainly been conceptual, with little empirical evidence or proof of concept in real world cases. The objective of this paper was to take stock of the rapidly advancing literature on the WEF nexus in irrigated agriculture, and to analyze how the concept was actually implemented in research studies, and how the nexus between water, food and energy was actually dealt with. The study period ranges from 2011 to 2019, and includes 194 articles. Results showed that the WEF nexus is indeed very relevant in irrigated agriculture, and the respective literature makes up one third of all WEF nexus papers. Modeling and empirical research have caught up with conceptual synthesis studies during the last four years, thereby indicating that the WEF nexus concept is indeed increasingly operationalized. However, most studies addressed the WEF nexus from a perspective of either socioeconomic, technological or environmental categories, and they place one of the dimensions of water, food or energy into the foreground. To address sustainable development, there is a need to fully integrate across research disciplines and thematic dimensions. Such studies are only starting to emerge. These findings are an important evidence-base for future WEF nexus research on irrigated agriculture, in support of sustainable solutions for water scarce regions, especially in settings undergoing transformations

INSTITUTIONAL ANALYSIS OF IRRIGATION MANAGEMENT IN UZBEKISTAN USING QUALITATIVE COMPARATIVE ANALYSIS: CASE STUDIES OF WATER CONSUMERS ASSOCIATIONS IN BUKHARA REGION

Given the fact that water consumers associations (WCAs) in Uzbekistan were established about a decade ago in a top-down fashion to maintain on-farm water facilities, using fuzzy set Qualitative Comparative Analysis tool this paper attempted at determining sets of conditions that are necessary and sufficient to achieve an outcome. The study followed the logic of abductive approach, where sets of theories were adjusted based on the empirical field stint. Institutional economics perspective was applied to identify rural farmers’ behavior in the management of common pool resources (CPRs). The study took place in Bukhara region – southwestern part of Uzbekistan – and involved focus group discussions with members of fifteen WCAs using semi-structured interview format. Three sets of conditions (appropriate chairmanship skills [ACS], proper water allocation [PWA], and effective participatory governance [EPG]) were found to be important for explaining the outcome (improved maintenance of irrigation canals [IMC]). The analysis of necessary conditions indicated that neither condition ACS nor PWA nor EPG is necessary for IMC on its own. The same finding was apparent for the complements of the three conditions, ~ACS, ~PWA, ~EPG. In the meantime, the analysis of necessary conditions for unions of conditions (logical OR) revealed that the terms of PWA OR EPG (i.e. PWA+EPG) is necessary to achieve the outcome. However, their presence is not sufficient. The result for sufficiency analysis highlighted that no single condition alone is sufficient to achieve IMC. The results for combinations of conditions showed that the presence of ACS AND PWA AND EPG (i.e. ACS*PWA*EPG) is sufficient for achieving the outcome, IMC. Therefore, it is reasonable to believe that when these conditions are present simultaneously, there is a great chance of improving CPR use within WCA territories

Impact of Climate Change on Groundwater Management in the Northwestern Part of Uzbekistan

Global climate change can have a significant impact on the development and sustainability of agricultural production. Climate scenarios indicate that an expected increase in air temperature in semiarid Uzbekistan can lead to an increase in evapotranspiration from agricultural fields, an increase in irrigation water requirements, and a deterioration in the ameliorative status of irrigated lands. The long-term mismanagement of irrigation practices and poor conditions of drainage infrastructure have led to an increase in the water table and its salinization level in the northwestern part of Uzbekistan. This article presents the results of an analysis of the amelioration of irrigated lands in the Khorezm region of Uzbekistan as well as the modeling of the dynamics of water table depths and salinity levels using the Mann–Kendall trend test and linear regression model. The study estimated the water table depths and salinity dynamics under the impact of climate change during 2020–2050 and 2050–2100. The results show that the water table depths in the region would generally decrease (from 1.72 m in 2050 to 1.77 m by 2100 based on the Mann–Kendall trend test; from 1.75 m in 2050 to 1.79 m by 2100 according to the linear regression model), but its salinity level would increase (from 1.72 g·L−1 in 2050 to 1.85 g·L−1 by 2100 based on the Mann–Kendall trend test; from 1.97 g·L−1 in 2050 to 2.1 g·L−1 by 2100 according to the linear regression model). The results of the study provide insights into the groundwater response to climate change and assist authorities in better planning management strategies for the region