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Santana, Otacilio Antunes, José Imaña Encinas, Bárbara Alves de Sousa, Sandra Razana Silva do Monte und Valéria Sandra de Oliveira Costa. „Aridy index over time in five ecosystems on semiarid“. Journal of Hyperspectral Remote Sensing 9, Nr. 3 (11.12.2019): 138. http://dx.doi.org/10.29150/jhrs.v9.3.p138-145.
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The local climate change was registered over time (1992-2018) on different land use ecosystems, in Brazilian Semiarid area. The aimed of this work was to analyze aridity index in five ecosystems (Wild Caatinga, Caatinga on management, Cactaceae field, Eucalyptus reforestation, and Fabaceae crop), and to compare this index with environment variables. Meteorological towers and measures with porometer and psychrometers were carried out to collect the data. The main result was that the studied areas are hotter and drier. The Fabaceae crop and Eucalyptus reforestation studied ecosystems already are on Arid classification according with registered aridity index. Wild Caatinga and Cactaceae field ecosystems are on Semiarid classification, and over time Caatinga on management ecosystem pass from Semiarid to Arid classification. The five ecosystems together are classified on Arid climate. The VPD and Ψsoil were the variables more directly proportional with Aridity index to analyzed ecosystems.
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Kirey, Vladimir V. „GLOBAL SYSTEMS OF ENVIRONMENTAL-ECONOMIC ACCOUNTING“. EKONOMIKA I UPRAVLENIE: PROBLEMY, RESHENIYA 11/2, Nr. 140 (2023): 82–88. http://dx.doi.org/10.36871/ek.up.p.r.2023.11.02.011.
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Throughout history, people have treated natural resources as infinite and free, which has led to their overexploitation and degradation of ecosystems. At present, society and industry are facing challenges caused by the degradation of ecosystems and the reduction of ecosystem service flows. With ecosystem accounting, we now have the ability to incorporate the value of biodiversity into policy and decision-making. Clear consideration of ecosystem contributions as to current ecosystems Market production, as well as the broader benefits accruing to individuals and society, contributes to a broader understanding of the role of ecosystems and the impacts that can arise when the scale and condition of ecosystems change. The purpose of this article is to provide stakeholders with a brief overview of existing classification systems and assessment frameworks for ecosystem accounting. To do this, we analyses four different ecosystem classification systems, including the Millennium Ecosystem Assessment, the Economics of Ecosystems and Biodiversity, the Common International Classification of Ecosystem Services, and the Intergovernmental Scientific Classification. - Policy Platform on Biodiversity and Ecosystem Services. This review will help to determine the most appropriate models for assessing ecosystem services and natural capital for use in Russia.
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Zhou, Yanqing, Yaoming Li, Wei Li, Feng Li und Qinchuan Xin. „Ecological Responses to Climate Change and Human Activities in the Arid and Semi-Arid Regions of Xinjiang in China“. Remote Sensing 14, Nr. 16 (12.08.2022): 3911. http://dx.doi.org/10.3390/rs14163911.
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Understanding the impacts and extent of both climate change and human activities on ecosystems is crucial to sustainable development. With low anti-interference ability, arid and semi-arid ecosystems are particularly sensitive to disturbances from both climate change and human activities. We investigated how and to what extent climate variation and human activities influenced major indicators that are related to ecosystem functions and conditions in the past decades in Xinjiang, a typical arid and semi-arid region in China. We analyzed the changing trends of evapotranspiration (ET), gross primary productivity (GPP) and leaf area index (LAI) derived from the Moderate-Resolution Imaging Spectroradiometer (MODIS) satellite product and the Breathing Earth System Simulator (BESS) model in Xinjiang for different climate zones. We separated and quantified the contributions of climate forcing and human activities on the trends of the studied ecosystem indicators using the residual analysis method for different climate zones in Xinjiang. The results show that GPP and LAI increased and ET decreased from 2001 to 2015 in Xinjiang. Factors that dominate the changes in ecosystem indicators vary considerably across different climate zones. Precipitation plays a positive role in impacting vegetation indicators in arid and hyper-arid zones and temperature has a negative correlation with both GPP and LAI in hyper-arid zones in Xinjiang. Results based on residual analysis indicate that human activities could account for over 72% of variation in the changes in each ecosystem indicator. Human activities have large impacts on each vegetation indicator change in hyper-arid and arid zones and their relative contribution has a mean value of 79%. This study quantifies the roles of climate forcing and human activities in the changes in ecosystem indicators across different climate zones, suggesting that human activities largely influence ecosystem processes in the arid and semi-arid regions of Xinjiang in China.
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Gu, Qing, Hui Zheng, Li Yao, Min Wang, Mingguo Ma, Xufeng Wang und Xuguang Tang. „Performance of the Remotely-Derived Products in Monitoring Gross Primary Production across Arid and Semi-Arid Ecosystems in Northwest China“. Land 9, Nr. 9 (22.08.2020): 288. http://dx.doi.org/10.3390/land9090288.
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As an important component to quantify the carbon budget, accurate evaluation of terrestrial gross primary production (GPP) is crucial for large-scale applications, especially in dryland ecosystems. Based on the in situ data from six flux sites in northwestern China from 2014 to 2016, this study compares seasonal and interannual dynamics of carbon fluxes between these arid and semi-arid ecosystems and the atmosphere. Meanwhile, the reliability of multiple remotely-derived GPP products in representative drylands was examined, including the Breathing Earth System Simulator (BESS), the Moderate Resolution Imaging Spectroradiometer (MODIS) and data derived from the OCO-2 solar-induced chlorophyll fluorescence (GOSIF). The results indicated that the carbon fluxes had clear seasonal patterns, with all ecosystems functioning as carbon sinks. The maize cropland had the highest GPP with 1183 g C m−2 y−1. Although the net ecosystem carbon exchange (NEE) in the Tamarix spp. ecosystem was the smallest among these flux sites, it reached 208 g C m−2 y−1. Furthermore, distinct advantages of GOSIF GPP (with R2 = 0.85–0.98, and RMSE = 0.87–2.66 g C m−2 d−1) were found with good performance. However, large underestimations in three GPP products existed during the growing seasons, except in grassland ecosystems. The main reasons can be ascribed to the uncertainties in the key model parameters, including the underestimated light use efficiency of the MODIS GPP, the same coarse land cover product for the BESS and MODIS GPP, the coarse gridded meteorological data, and distribution of C3 and C4 plants. Therefore, it still requires more work to accurately quantify the GPP across these dryland ecosystems.
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Tate, Robert L. „Arid Ecosystems“. Soil Science 160, Nr. 6 (Dezember 1995): 453. http://dx.doi.org/10.1097/00010694-199512000-00015.
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Ávila Flores, Diana Yemilet, Dora Alicia García García und David Castillo Quiroz. „Caracterización ecológica en parcelas afectadas por incendios en el sureste de Coahuila, México“. E-CUCBA 10, Nr. 20 (29.06.2023): 114–20. http://dx.doi.org/10.32870/ecucba.vi20.303.
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Among the factors that influence the composition, structure, functioning and dynamics of ecosystems, fire is one of the mostimportant and widespread in the world. Knowledge about the dynamics of post-fire recovery of the vegetation constitutes the basisfor the management of areas impacted by forest fires; the above is more important when it comes to areas with little information onthe response of vegetation to fire, such as the vegetation of semi-arid ecosystems. The objective of this study was to characterize thebiodiversity of the vegetation in experimental plots, which were affected by a forest fire, through the ecological parameters ofabundance (ARi), dominance (DRi), frequency (FRi) and importance value index. (IVI) in order to determine the floristiccomposition of post-fire areas in semi-arid zones. Despite the fact that biodiversity has been affected as shown by the resultsobtained, since these are dominated by a single species (Quercus pringlei Seemen ex Loes.), the tendency they show is to recovernaturally as indicated by the results, values of ecological importance where Yucca carnerosana (Trel.) McKelvey stands out as anelement that gives support and structure to the ecosystem. The study of post-fire recovery dynamics in semi-arid areas of Mexico isof the utmost importance, since it is valuable information that contributes to knowledge to address the risks that may arise during aforest fire, to generate initiatives for its conservation.
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Schreieck, Maximilian, Manuel Wiesche und Helmut Krcmar. „From Product Platform Ecosystem to Innovation Platform Ecosystem: An Institutional Perspective on the Governance of Ecosystem Transformations“. Journal of the Association for Information Systems 23, Nr. 6 (2022): 1354–85. http://dx.doi.org/10.17705/1jais.00764.
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Incumbent companies across industries such as banking, insurance, and enterprise software have begun transforming their existing product platform ecosystems into innovation platforms ecosystems to increase generativity in their ecosystems. Such ecosystem transformations not only entail technological challenges as the underlying platform technology changes but also organizational challenges in that ecosystem actors such as partners and customers need to become part of the transformed ecosystem. To study how incumbent companies can govern ecosystem transformations successfully, we interpret ecosystems as organizational fields and ecosystem transformations as changes to the fields’ institutional infrastructure. Based on a multiyear, grounded theory study of the transformation of SAP’s on-premises ERP system, we first identify institutionalization challenges that arise when institutional infrastructure is changed during an ecosystem transformation. We then show how field-level governance mechanisms address these challenges and how the new institutional infrastructure gains legitimacy among ecosystem actors, ultimately leading to the institutionalization of the transformed ecosystem. These findings contribute to the literature on ecosystem transformations and platform governance by highlighting the role that institutional forces play in ecosystem transformations. Furthermore, we add to the literature on institutional theory by providing insights into the dynamics of institutional infrastructure as it becomes infused with digital technologies.
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Atazadeh, Ehsan, Andrew Barton, Mozhgan Shirinpour, Mahdi Zarghami und Abbas Rajabifard. „River management and environmental water allocation in regulated ecosystems of arid and semi-arid regions – A review“. Fundamental and Applied Limnology / Archiv für Hydrobiologie 193, Nr. 4 (23.06.2020): 327–45. http://dx.doi.org/10.1127/fal/2020/1286.
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Rivers make a significant contribution in providing goods and services for human well-being. Today, many rivers and streams have been heavily regulated to ensure adequate provision of water resources for anthropogenic uses. Riverine ecosystems, especially those in arid and semi-arid regions, are experiencing severe stress due to the increasing demands on the ecosystem services they provide, coupled with anthropogenic catchment-scale impacts and factors associated with natural and human-induced climate variability and change. In this paper, the various flow components in regulated riverine ecosystems and the methods to determine environmental flows are reviewed. The review also focuses on the concurrent developments of eco-hydrological models and on the new opportunities for improving environmental flows of rivers by sustainably adjusting consumptive flows to fine-tune environmental flows and maximize the ecological benefit. In fact, the present paper highlights the role of consumptive flows, towards improving environmental flows, which has largely been neglected by river scientists and water managers. Indeed, consumptive flows can provide an opportunity to improve and support environmental flows in regulated riverine ecosystems. Addressing these challenges may aid water management efforts in finding sustainable solutions in riverine ecosystems by balancing environmental/ecological and human water requirements.
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Glettler, Christiana, und Gregor Torkar. „First-Year Pre-service Primary School Teachers’ Conceptual Structure of Ecosystem Ecology Concepts“. Action Research and Innovation in Science Education 4, Nr. 1 (01.10.2021): 25–31. http://dx.doi.org/10.51724/arise.41.
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Science education research has been increasingly concerned with students’ and teachers’ conceptions of central scientific concepts over the past decades. However, science teaching today should not only convey knowledge but also values and science practices in order to empower students to become responsible citizens in a world that is facing ecological as well as social problems. Thus, a profound understanding of ecology and systems thinking skills are seen as paramount. This paper explores first-year pre-service primary school teachers’ conceptual understanding of ecology through the use of a word association test. Students were given four stimulus words and asked to provide five response words to each stimulus. Furthermore, they were asked to formulate a sentence related to biology, using each stimulus word. Response words were categorised and the frequency of the words was calculated. The findings show very limited understanding of the ecological concepts and their interrelatedness. Furthermore, the students showed numerous misconceptions regarding energy flow and food chain relationships. Thus our findings support other authors’ propositions that students often struggle with understanding ecology concepts. The findings further imply that the instruction students receive at school is not successful in replacing existing misconceptions with accurate science concepts.
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Guan, K., S. P. Good, K. K. Caylor, H. Sato, E. F. Wood und H. Li. „Continental-scale impacts of intra-seasonal rainfall variability on simulated ecosystem responses in Africa“. Biogeosciences 11, Nr. 23 (11.12.2014): 6939–54. http://dx.doi.org/10.5194/bg-11-6939-2014.
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Abstract. Climate change is expected to modify intra-seasonal rainfall variability, arising from shifts in rainfall frequency, intensity and seasonality. These intra-seasonal changes are likely to have important ecological impacts on terrestrial ecosystems. Yet, quantifying these impacts across biomes and large climate gradients is largely missing. This gap hinders our ability to better predict ecosystem services and their responses to climate change, especially for arid and semi-arid ecosystems. Here we use a synthetic weather generator and an independently validated vegetation dynamic model (SEIB-Dynamic Global Vegetation Model, DGVM) to virtually conduct a series of "rainfall manipulation experiments" to study how changes in the intra-seasonal rainfall variability affect continent-scale ecosystem responses across Africa. We generate different rainfall scenarios with fixed total annual rainfall but shifts in (i) frequency vs. intensity, (ii) rainy season length vs. frequency, (iii) intensity vs. rainy season length. These scenarios are fed into SEIB-DGVM to investigate changes in biome distributions and ecosystem productivity. We find a loss of ecosystem productivity with increased rainfall frequency and decreased intensity at very low rainfall regimes (<400 mm year−1) and low frequency (<0.3 event day−1); beyond these very dry regimes, most ecosystems benefit from increased frequency and decreased intensity, except in the wet tropics (>1800 mm year−1) where radiation limitation prevents further productivity gains. This result reconciles seemingly contradictory findings in previous field studies on the impact of rainfall frequency/intensity on ecosystem productivity. We also find that changes in rainy season length can yield more dramatic ecosystem responses compared with similar percentage changes in rainfall frequency or intensity, with the largest impacts in semi-arid woodlands. This study demonstrates that intra-seasonal rainfall characteristics play a significant role in influencing ecosystem function and structure through controls on ecohydrological processes. Our results suggest that shifts in rainfall seasonality have potentially large impacts on terrestrial ecosystems, and these understudied impacts should be explicitly examined in future studies of climate impacts.
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Alqallaf, Ahmed, Bader Al-Anzi und Meshal Alabdullah. „Assessing the Effectiveness of Supplemental Irrigation to Improve Soil Moisture in an Arid Ecosystem with an Emphasis on Climate Change: A Case Study from the State of Kuwait“. Sustainability 12, Nr. 21 (01.11.2020): 9104. http://dx.doi.org/10.3390/su12219104.
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Arid ecosystems are extremely vulnerable to climate change, which is considered one of the serious global environmental issues that can cause critical challenges to the hydrological cycle in arid ecosystems. This work focused on assessing the effectiveness of supplemental irrigation to improve the actual soil moisture content in arid ecosystems and considering climate change impacts on soil moisture. The study was conducted at two fenced protected sites in Kuwait. The first site is naturally covered with Rhanterietum epapposum, whereas the other study site is a supplemented irrigated site, containing several revegetated native plants. The results showed that supplemental irrigation highly improved soil moisture (∆SM) during the winter season by >50%. However, during the summer season, the rainfed and irrigated site showed low ∆SM due to the high temperature and high evapotranspiration (ET) rates. We also found that ∆SM would negatively get impacted by climate change. The climate change projection results showed that temperature would increase by 12%–23%, ET would increase by 17%–19%, and precipitation would decrease by 31%–46% by 2100. Such climate change impacts may also shift the current ecosystem from an arid to a hyper-arid ecosystem. Therefore, we concluded that irrigation is a practical option to support the ∆SM during the low-temperature months only (spring and winter) since the results did not show any progress during the summer season. It is also essential to consider the possibility of future shifting in ecosystems and plant communities in restoration and revegetation planning.
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Xu, Lili, Tianyu Chen, Baolin Li, Yecheng Yuan und Nandin-Erdene Tsendbazar. „Spatiotemporal Evolution of Arid Ecosystems Using Thematic Land Cover Products“. Remote Sensing 15, Nr. 12 (19.06.2023): 3178. http://dx.doi.org/10.3390/rs15123178.
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The pathway, direction, and potential drivers of the evolution in global arid ecosystems are of importance for maintaining the stability and sustainability of the global ecosystem. Based on the Climate Change Initiative Land Cover dataset (CCILC), in this study, four indicators of land cover change (LCC) were calculated, i.e., regional change intensity (RCI), rate of change in land cover (CR), evolutionary direction index (EDI), and artificial change percentage (ACP), to progressively derive the intensity, rate, evolutionary direction, and anthropogenic interferences of global arid ecosystems. The LCC from 1992 to 2020 and from 28 consecutive pair-years was observed at the global, continental, and country scales to examine spatiotemporal evolution in the Earth’s arid ecosystems. The following main results were obtained: (1) Global arid ecosystems experienced positive evolution despite complex LCCs and anthropogenic interferences. Cautious steps to avoid potential issues caused by rapid urbanization and farmland expansion are necessary. (2) The arid ecosystems in Australia, Central Asia, and southeastern Africa generally improved, as indicated by EDI values, but those in North America were degraded, with 41.1% of LCCs associated with urbanization or farming. The arid ecosystems in South America also deteriorated, but 83.4% of LCCs were in natural land covers. The arid ecosystems in Europe slightly improved with overall equivalent changes in natural and artificial land covers. (3) Global arid ecosystems experienced three phases of change based on RCI values: ‘intense’ (1992–1998), ‘stable’ (1998–2014), and ‘intense’ (2014–2020). In addition, two phases of evolution based on EDI values were observed: ‘deterioration’ (1992–2002) and ‘improvement’ (2002–2020). The ACP values indicated that urbanization and farming activities contributed increasingly less to global dryland change since 1992. These findings provide critical insights into the evolution of global arid ecosystems based on analyses of LCCs and will be beneficial for sustainable development of arid ecosystems worldwide within the context of ongoing climate change.
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Maestre, Fernando T., Matthew A. Bowker, Cristina Escolar, María D. Puche, Santiago Soliveres, Sara Maltez-Mouro, Pablo García-Palacios, Andrea P. Castillo-Monroy, Isabel Martínez und Adrián Escudero. „Do biotic interactions modulate ecosystem functioning along stress gradients? Insights from semi-arid plant and biological soil crust communities“. Philosophical Transactions of the Royal Society B: Biological Sciences 365, Nr. 1549 (12.07.2010): 2057–70. http://dx.doi.org/10.1098/rstb.2010.0016.
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Climate change will exacerbate the degree of abiotic stress experienced by semi-arid ecosystems. While abiotic stress profoundly affects biotic interactions, their potential role as modulators of ecosystem responses to climate change is largely unknown. Using plants and biological soil crusts, we tested the relative importance of facilitative–competitive interactions and other community attributes (cover, species richness and species evenness) as drivers of ecosystem functioning along stress gradients in semi-arid Mediterranean ecosystems. Biotic interactions shifted from facilitation to competition along stress gradients driven by water availability and temperature. These changes were, however, dependent on the spatial scale and the community considered. We found little evidence to suggest that biotic interactions are a major direct influence upon indicators of ecosystem functioning (soil respiration, organic carbon, water-holding capacity, compaction and the activity of enzymes related to the carbon, nitrogen and phosphorus cycles) along stress gradients. However, attributes such as cover and species richness showed a direct effect on ecosystem functioning. Our results do not agree with predictions emphasizing that the importance of plant–plant interactions will be increased under climate change in dry environments, and indicate that reductions in the cover of plant and biological soil crust communities will negatively impact ecosystems under future climatic conditions.
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El-Madany, Tarek S., Arnaud Carrara, M. Pilar Martín, Gerardo Moreno, Olaf Kolle, Javier Pacheco-Labrador, Ulrich Weber, Thomas Wutzler, Markus Reichstein und Mirco Migliavacca. „Drought and heatwave impacts on semi-arid ecosystems' carbon fluxes along a precipitation gradient“. Philosophical Transactions of the Royal Society B: Biological Sciences 375, Nr. 1810 (07.09.2020): 20190519. http://dx.doi.org/10.1098/rstb.2019.0519.
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The inter-annual variability (IAV) of the terrestrial carbon cycle is tightly linked to the variability of semi-arid ecosystems. Thus, it is of utmost importance to understand what the main meteorological drivers for the IAV of such ecosystems are, and how they respond to extreme events such as droughts and heatwaves. To shed light onto these questions, we analyse the IAV of carbon fluxes, its relation with meteorological variables, and the impact of compound drought and heatwave on the carbon cycle of two similar ecosystems, along a precipitation gradient. A four-year long dataset from 2016 to 2019 was used for the FLUXNET sites ES-LMa and ES-Abr, located in central (39°56'25″ N 5°46'28″ W) and southeastern (38°42'6″ N 6°47'9″ W) Spain. We analyse the physiological impact of compound drought and heatwave on the dominant tree species, Quercus ilex. Our results show that the gross primary productivity of the wetter ecosystem was less sensitive to changes in soil water content, compared to the dryer site. Still, the wetter ecosystem was a source of CO 2 each year, owing to large ecosystem respiration during summer; while the dry site turned into a CO 2 sink during wet years. Overall, the impact of the summertime compound event on annual CO 2 fluxes was marginal at both sites, compared to drought events during spring or autumn. This highlights that drought timing is crucial to determine the annual carbon fluxes in these semi-arid ecosystems. This article is part of the theme issue ‘Impacts of the 2018 severe drought and heatwave in Europe: from site to continental scale’.
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Hou, Jian, Menghan Wu und Haobo Feng. „Applying Trait-Based Modeling to Achieve Functional Targets during the Ecological Restoration of an Arid Mine Area“. Agronomy 12, Nr. 11 (13.11.2022): 2833. http://dx.doi.org/10.3390/agronomy12112833.
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(1) Background: Because ecosystem degradation has become a global phenomenon which seriously affects the health of natural ecosystems and human well-being, restoration of degraded ecosystems has attracted increasing attention. However, many of the methods used in current ecological restoration work have rarely combined ecological restoration practices with the quantitative goal of restoring ecosystem function. (2) Methods: In this study, based on the conceptual framework of response-effect traits and Community Assembly by Trait Selection model (CATS model), a restoration strategy for a degraded abandoned mine in Wuhai City, China has been provided. This restoration strategy connected the ecosystem function targets to the appropriate recovery species and their required abundances. (3) Results: The results showed that a relative abundance ratio of 8:2 for S. grandis to B. dasyphylla was best for a shady slope, while a 6:4 ratio of K. tragus to B. dasyphylla was best for repair on a sunny slope of the degraded mine area. (4) Conclusion: This study provides a typical example of applying ecological theory in practice that will be useful for current and future studies and applications. This approach will ensure that governance efforts to restore degraded ecosystems are effective and efficient.
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Baccarani, Claudio, und Fabio Cassia. „Evaluating the outcomes of service ecosystems“. TQM Journal 29, Nr. 6 (09.10.2017): 834–46. http://dx.doi.org/10.1108/tqm-04-2017-0039.
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Purpose The purpose of this paper is to understand how the resource integration processes that occur within service ecosystems affect both the well-being of the entire ecosystem and the well-being of specific focal actors (i.e. customers) in the ecosystem. Specifically, this paper considered cases in which customers’ well-being results from simultaneous participation in a multiplicity of service ecosystems. Design/methodology/approach An illustrative example, taken from the tourism context, was used to develop a conceptual framework (of which customers were the focal actors) to evaluate service ecosystem outcomes. Findings The results showed that the well-being of focal actors (i.e. customers) should be evaluated by considering the outcomes that arise in the interlocking service ecosystems in which the customers simultaneously participate. Further, in relation to these interlocking service ecosystems, high levels of well-being within a single ecosystem did not necessarily cause focal actors to experience high levels of well-being. Research limitations/implications To ensure the creation of positive customer experiences, the co-creating actors (e.g. the service providers) must first identify each of the interlocking service ecosystems in which customers simultaneously participate and then establish interactions with other relevant actors. Originality/value By considering the complex relationships between the well-being of a service ecosystem as a whole and the well-being of specific focal actors (e.g. customers) in an ecosystem, this study advances knowledge about evaluations on the performance of service ecosystems.
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Luković, Milica, und Urban Šilc. „Management of continental saline ecosystems in the Republic of Serbia: Are these ecosystems suitable for nature-based tourism?“ Menadzment u hotelijerstvu i turizmu 9, Nr. 2 (2021): 37–49. http://dx.doi.org/10.5937/menhottur2102037l.
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Continental saline habitats represent unique, authentic and rare ecosystems. These ecosystems are typically distributed in arid and semi-arid regions; however, they are also found in inland areas in temperate climate zones. Usually, the general public is not familiar with this particular type of ecosystem. In order to present saline habitats to tourists, a broadly applied method of ecosystem suitability assessment (ESI-ecosystem suitability index) was used and adjusted to the purposes of this research. The research aims to estimate the nature-based tourism potentials of selected sites. Thus, six representative halophytic habitats distributed along the geographic gradient, from the Pannonian Plain to the south of Serbia, were chosen. In terms of each site, seven indicators (e.g., flora and vegetation, bird fauna, landscape, protection status, accessibility, and ecotourism facilities), important for nature-based tourism, were analyzed. The results show that the Pannonian saline habitats have greater opportunities for development of this type of tourism in almost all categories compared to southern sites.
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Khosravi Mashizi, Azam, und Mohsen Sharafatmandrad. „Assessing the effects of shrubs on ecosystem functions in arid sand dune ecosystems“. Arid Land Research and Management 34, Nr. 2 (02.07.2019): 171–87. http://dx.doi.org/10.1080/15324982.2019.1634655.
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Zou, Jie, Jianli Ding, Shuai Huang und Bohua Liu. „Ecosystem Resistance and Resilience after Dry and Wet Events across Central Asia Based on Remote Sensing Data“. Remote Sensing 15, Nr. 12 (18.06.2023): 3165. http://dx.doi.org/10.3390/rs15123165.
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Climate change forecasts indicate that the frequency and intensity of extreme climate events will increase in the future; these changes will have important effects on ecosystem stability and function. An important arid region of the world, Central Asia has ecosystems that are extremely vulnerable to extreme weather events. However, few studies have investigated the resistance and resilience of this region’s ecosystems to extreme weather events. In this study, first, the extreme drought/wet threshold was calculated based on the 113-year (1901–2013) standardized precipitation–evapotranspiration index (SPEI); second, moderate resolution imaging spectroradiometer (MODIS) remote sensing data were applied to calculate ecosystem water use efficiency (WUE) and quantify ecosystem resistance and resilience after different extreme climate events; and finally, differences in the changes of various ecosystem types before and after climate events were assessed. The results showed the following: (1) The average SPEI was 0.073, and the thresholds of extreme wetness and drought were 0.91 and −0.67, respectively. Central Asia experienced extreme wet periods in 2002 and 2003 and a drought period in 2008. (2) Suitable wetness levels can increase the resistance of an ecosystem; however, continuous wetness reduces ecosystem resistance, as does drought. Wet areas had strong resilience after wet events, and arid areas had strong resilience after drought events. (3) During both wet and drought years, the transition between shrubland and grassland caused changes in ecosystem resistance and resilience. These findings are important for understanding the impact of future climate change on ecosystem stability.
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Chen, Ying Ying, Huan Yang, Gen Sheng Bao, Xiao Pan Pang und Zheng Gang Guo. „Effect of the presence of plateau pikas on the ecosystem services of alpine meadows“. Biogeosciences 19, Nr. 18 (19.09.2022): 4521–32. http://dx.doi.org/10.5194/bg-19-4521-2022.
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Abstract. The activity of small mammalian herbivores influences grassland ecosystem services in arid and semi-arid regions. Plateau pika (Ochotona curzoniae) was considered to be a focal organism to investigate the effect of small mammalian herbivores on meadow ecosystem services in alpine regions. In this study, a home-range scale was used to measure the forage available to livestock, water conservation, carbon sequestration and soil nutrient maintenance (total nitrogen, phosphorus and potassium) in the topsoil layer, and a quadrat scale was used to assess the biodiversity conservation of alpine meadows. This study showed that the forage available to livestock and water conservation was 19 % and 16 % lower in the presence of plateau pikas than in their absence, and biodiversity conservation, carbon sequestration, soil nitrogen and phosphorus maintenance was 15 %, 29 %, 10 % and 8.9 % higher in the presence of plateau pikas than in their absence. In contrast, it had no impact on soil potassium maintenance of meadow ecosystems in alpine regions. The forage available to livestock, biodiversity conservation and soil nutrient maintenance of meadow ecosystems in alpine regions had maximum values as the disturbance intensity of plateau pikas increased; the water conservation tended to decrease linearly with the increasing disturbance intensity of plateau pikas. These results present a pattern of plateau pikas influencing the ecosystem services of meadow ecosystems in alpine regions, enriching our understanding of the small mammalian herbivores in relation to grassland ecosystem service.
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Azizah, Isnaniar Rahmatul, Rahmatia Harahap, Betty Natalie Fitriatin, Nadia N. Kamaluddin und Tualar Simarmata. „ABUNDANCE OF N2-FIXING RHIZOBACTERIA OF DIFFERENT DRYLAND AGRICULTURE ECOSYSTEMS IN DRY CLIMATE ZONE OF LOMBOK-INDONESIA“. International Journal of Agriculture, Environment and Bioresearch 07, Nr. 05 (2022): 24–35. http://dx.doi.org/10.35410/ijaeb.2022.5761.
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Soil microbial communities are crucial in ecosystem diversity and are directly related to soil fertility. Lombok is an island in central Indonesia that has low soil fertility and a limited amount of available water. Beneficial microorganisms can be used as a low-cost and environmental friendly tool to increase productivity in dryland agriculture systems. Screening to obtain superior rhizosphere bacteria is one of the options to support the nutrient supply in arid soils. Composites soil samples were taken from five ecosystems in Lombok, West Nusa Tenggara, an arid region in the eastern part of Indonesia to obtain the isolates of nitrogen-fixer rhizobacteria (NFR). Nine Azotobacter and Azopirillium spp were isolated from, rainfed, maize, mixed crop, natural forests, and savanna ecosystems. Abundance of total bacteria and N2-fixers in all ecosystems was relatively high (more than 108 cfu g-1), and the highest total population was recorded in the natural forest. The abundance of N2-fixer rhizobacteria recorded the highest Azotobacter population at 2.64 x 108 cfu g-1 in the maize ecosystem and the highest Azospirillum population at 2.32 x 108 cfu g-1 in the natural forest ecosystem. Additionally, the highest contain of organic C and total nitrogen were obtained in natural forest and savanna ecosystem. Eighteen isolates were obtained and characterized microscopic and macroscopically, consisted of nine Azotobacter sp and nine Azospirillium isolates which are potentially to be used as biogent for improving the growth of upland rice on dry climate zone.
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Fan, Xin, Haoran Yu, Damien Sinonmatohou Tiando, Yuejing Rong, Wenxu Luo, Chan Eme, Shengya Ou, Jiangfeng Li und Zhe Liang. „Impacts of Human Activities on Ecosystem Service Value in Arid and Semi-Arid Ecological Regions of China“. International Journal of Environmental Research and Public Health 18, Nr. 21 (22.10.2021): 11121. http://dx.doi.org/10.3390/ijerph182111121.
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The quantitative and spatial–temporal variations in the characteristics of ecosystem value can be helpful to improve environmental protection and climate adaptation measures and adjust the balance between economic development and the ecological environment. The arid and semi-arid regions of China are undergoing the effects of climate change across the entire northern hemisphere. Their ecological environments are fragile and in conflict with anthropogenic activities, which significantly altered more ecosystems services in these regions. Therefore, estimating the effects of anthropogenic activities on ecosystem services is important for formulating ecological policy and regional environmental mitigation plans of these regions. This study employed the model of ecosystem service value (ESV) assessment and the bivariate spatial autocorrelation method to reveal the spatiotemporal variations in the characteristics of ecosystem value in the arid and semi-arid ecological regions of China and its interaction with human activities. Results showed that (1) the total value of ES of the study area increased from USD 487,807 billion in 2000 to USD 67,831,150 billion 2020; (2) the ES value provided by forest land first increased by 5.60% from 2000 to 2020; (3) the ESV provided by grassland showed an overall decline over the 20 years. Food and raw material production showed the lowest ES value, and climate regulation and soil conservation decreased from 2000 to 2020; (4) the index of human footprint patches decreased from 45.80% in 2000 to 17.63% in 2020, while the high and very high human footprint index areas increased significantly, mainly due to the rapid urbanization and improvement of railway networks in these areas. Spatially, the regions with high human footprint were mostly dispersed in the northeastern of China such as Shanxi and Gansu, whereas the regions with a low human footprint remained mainly located in the central and southwestern parts of China; (5) significant spatial dependencies between changes in ESV and the human footprint index were recorded. Our study could provide a scientific basis for ecosystem functions regulation and land development security in arid and semi-arid ecological regions.
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Brandyk, Andrzej, Grzegorz Majewski, Marcin Krukowski und Anna Baryła. „Sustainable management of different valley ecosystems“. SHS Web of Conferences 57 (2018): 02002. http://dx.doi.org/10.1051/shsconf/20185702002.
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Development and conservation of valley ecosystems has been an important issue for a long time, with respect to extensive, interdisciplinary research problems, offered ecosystem services and wide public interest. It has been as yet controversial, which indicators would describe the achievement of particular environmental status by those ecosystems, since they tend to be rather complex, showing fragile equilibrium and high vulnerability. With the use of hydrological modelling and proper criteria we demonstrated possibilities to balance well the concern for managers to control features regarding ecosystem health. It was evident during different hydroperiods, that ground water inflow conditions, influenced by investments into hydraulic structures functioning, arise as driving factor for environmental and ecological disturbance.
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Abdullah, Meshal M., Amjad T. Assi und Nasser B. Asadalla. „Integrated Ecosystem Sustainability Approach: Toward a Holistic System of Thinking of Managing Arid Ecosystems“. Open Journal of Ecology 09, Nr. 11 (2019): 493–505. http://dx.doi.org/10.4236/oje.2019.911032.
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Xue, Bing, Yaotian Xu und Jun Yang. „Remote Sensing of the Interaction between Human and Natural Ecosystems in Asia“. Remote Sensing 16, Nr. 13 (21.06.2024): 2255. http://dx.doi.org/10.3390/rs16132255.
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Human and natural ecosystems refer to human–social–economic subsystems and natural–ecological subsystems and their interactions. Understanding the interactions between human and natural ecosystems is essential for regional sustainability. However, the coupled human–nature ecosystem is usually highly heterogeneous and both spatially and temporally complex, so it is difficult to accurately identify and quantify the interaction between human and natural ecosystems at a large scale. This results in a poor understanding and evaluation of its impact on regional sustainability. Therefore, given the increasing interaction between humans and the natural ecosystem, our Special Issue collated 11 contributions from Asian scholars focusing on the latest research advances in remote sensing technologies and their application to observing, understanding, modeling, and explaining the interaction between human and natural ecosystems. This research involves the development of innovative methods, indicators, and frameworks implementing different perspectives and spatio-temporal scales, covering urban, arid, plateau, watershed, and marine regions in Asia and promoting the sustainable development of regional human and natural ecosystems.
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Leach, Melissa, Bernard Bett, M. Said, Salome Bukachi, Rosemary Sang, Neil Anderson, Noreen Machila et al. „Local disease–ecosystem–livelihood dynamics: reflections from comparative case studies in Africa“. Philosophical Transactions of the Royal Society B: Biological Sciences 372, Nr. 1725 (05.06.2017): 20160163. http://dx.doi.org/10.1098/rstb.2016.0163.
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This article explores the implications for human health of local interactions between disease, ecosystems and livelihoods. Five interdisciplinary case studies addressed zoonotic diseases in African settings: Rift Valley fever (RVF) in Kenya, human African trypanosomiasis in Zambia and Zimbabwe, Lassa fever in Sierra Leone and henipaviruses in Ghana. Each explored how ecological changes and human–ecosystem interactions affect pathogen dynamics and hence the likelihood of zoonotic spillover and transmission, and how socially differentiated peoples’ interactions with ecosystems and animals affect their exposure to disease. Cross-case analysis highlights how these dynamics vary by ecosystem type, across a range from humid forest to semi-arid savannah; the significance of interacting temporal and spatial scales; and the importance of mosaic and patch dynamics. Ecosystem interactions and services central to different people's livelihoods and well-being include pastoralism and agro-pastoralism, commercial and subsistence crop farming, hunting, collecting food, fuelwood and medicines, and cultural practices. There are synergies, but also tensions and trade-offs, between ecosystem changes that benefit livelihoods and affect disease. Understanding these can inform ‘One Health’ approaches towards managing ecosystems in ways that reduce disease risks and burdens. This article is part of the themed issue ‘One Health for a changing world: zoonoses, ecosystems and human well-being’.
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García-Llorente, Marina, Antonio J. Castro, Cristina Quintas-Soriano, Elisa Oteros-Rozas, Irene Iniesta-Arandia, José González, David García del Amo et al. „Local Perceptions of Ecosystem Services Across Multiple Ecosystem Types in Spain“. Land 9, Nr. 9 (18.09.2020): 330. http://dx.doi.org/10.3390/land9090330.
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Combining socio-cultural valuations of ecosystem services with ecological and monetary assessments is critical to informing decision making with an integrative and multi-pronged approach. This study examined differences in the perceptions of ecosystem service supply and diversity across eight major ecosystem types in Spain and scrutinized the social and ecological factors shaping these perceptions. First, we implemented 1932 face-to-face questionnaires among local inhabitants to assess perceptions of ecosystem service supply. Second, we created an ecosystem service diversity index to measure the perceived diversity of services considering agroecosystems, Mediterranean mountains, arid systems, two aquatic continental systems, coastal ecosystems and two urban ecosystems. Finally, we examined the influence of biophysical, socio-demographic and institutional factors in shaping ecosystem service perceptions. Overall, cultural services were the most widely perceived, followed by provisioning and regulating services. Provisioning services were most strongly associated with agroecosystems, mountains and coastal systems, whereas cultural services were associated with urban ecosystems and regulating services were specifically linked with agroecosystems, mountains and urban recreational areas. The highest service diversity index values corresponded to agroecosystems, mountains and wetlands. Our results also showed that socio-demographic factors, such as place of origin (urban vs. rural) and educational level, as well as institutional factors, such as management and access regimes, shaped the perception of ecosystem services.
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Chen, Qi, Yuhua Xing, Dapeng Zhang, Haitao Sun und Pei Wang. „Water Budget, Biological Water Use, and the Soil Hydrological Cycle across Typical Ecosystems of the Heihe River Basin“. Water 14, Nr. 18 (16.09.2022): 2895. http://dx.doi.org/10.3390/w14182895.
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Quantification of the water budget of an arid inland river ecosystem is essential but still a challenge for the sustainable development of water resources. In situ observed data were used to analyze the monthly and annual water budgets and the soil hydrological cycle for six typical ecosystems in the Heihe River Basin (HRB). The two-source model was used to partition evapotranspiration (ET) into transpiration (T) and evaporation, after which the validated model was applied to quantitatively analyze the biological water use fraction [T/Ecosystem Water Supply (WS)] for different ecosystems. There were differences in the water budgets of the different ecosystems due to differences in climate, vegetation, soil, and external inputs. Precipitation in the HRB decreased from upstream to downstream, whereas there was a gradual increase in ET. External sources of water (e.g., natural runoff from upstream, irrigation in the middle reaches, and groundwater recharge in the lower reaches) to soil layers played an important role in regulating the water budgets of HRB ecosystems. Cropland obtained the maximum biological water use fraction (0.50), followed by Populus euphratica (0.49), alpine meadow (0.49), alpine swamp meadow (0.44), Tamarix ramosissima (0.42), and Kalidium foliatum (0.4). The soil water residence time (at a depth of 40 cm) varied from 14 d to 97 d (average of 60 d). The order of plant species in terms of soil water residence time was: K. foliatum (88 d) > T. ramosissima (72 d) > alpine meadow (68 d) > alpine swamp meadow (63 d) > cropland (53 d) > P. euphratica forest (20 d). Differences in the biological water use fraction and soil water residence time could be attributed to the characteristics of the water budget for each ecosystem. This study quantified the water budget, biological water use, and soil hydrological cycle across typical ecosystems in HRB, and can act as a reference for ecosystem management of the arid inland river basin.
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Eamus, D., S. Zolfaghar, R. Villalobos-Vega, J. Cleverly und A. Huete. „Groundwater-dependent ecosystems: recent insights, new techniques and an ecosystem-scale threshold response“. Hydrology and Earth System Sciences Discussions 12, Nr. 5 (04.05.2015): 4677–754. http://dx.doi.org/10.5194/hessd-12-4677-2015.
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Abstract. Groundwater-dependent ecosystems (GDEs) are at risk globally due to unsustainable levels of groundwater extraction, especially in arid and semi-arid regions. In this review, we examine recent developments in the ecohydrology of GDEs with a focus on three knowledge gaps: (1) how do we locate GDEs, (2) how much water is transpired from shallow aquifers by GDEs; and (3) what are the responses of GDEs to excessive groundwater extraction? The answers to these questions will determine water allocations that are required to sustain functioning of GDEs and to guide regulations on groundwater extraction to avoid negative impacts on GDEs. We discuss three methods for identifying GDEs: (1) fluctuations in depth-to-groundwater that are associated with diurnal variations in transpiration, (2) stable isotope analysis of water sources in the transpiration stream; and (3) remote sensing methods. We then discuss several methods for estimating rates of GW use, including direct measurement using sapflux or eddy covariance technologies, estimation of a climate wetness index within a Budyko framework, spatial distribution of ET using remote sensing, groundwater modelling and stable isotopes. Remote sensing methods often rely on direct measurements to calibrate the relationship between vegetation indices and ET. ET from GDEs is also determined using hydrologic models of varying complexity, from the "White method" to fully coupled, variable saturation models. Combinations of methods are typically employed to obtain clearer insight into the components of groundwater discharge in GDEs, such as the proportional importance of transpiration vs. evaporation (e.g., using stable isotopes) or from groundwater vs. rainwater sources. Groundwater extraction can have severe consequences on structure and function of GDEs. In the most extreme cases, phreatophytes experience crown dieback and death following groundwater drawdown. We provide a brief review of two case studies of the impacts of GW extraction and discuss the use of C isotope ratios in xylem to reveal past influences of GW extraction. We conclude with a discussion of a depth-to-groundwater threshold in mesic and semi-arid GDEs. Across this threshold, significant changes occur in ecosystem structure and function.
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Cai, Peng, Chaofan Li, Geping Luo, Chi Zhang, Friday Uchenna Ochege, Steven Caluwaerts, Lesley De Cruz et al. „The Responses of the Ecosystems in the Tianshan North Slope under Multiple Representative Concentration Pathway Scenarios in the Middle of the 21st Century“. Sustainability 12, Nr. 1 (06.01.2020): 427. http://dx.doi.org/10.3390/su12010427.
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The arid ecosystem is fragile and sensitive to the changes in climate and CO2 concentration. Exploring the responses of the arid ecosystem to the changes under different representative concentration pathways (RCPs) is of particular significance for the sustainable development of the ecosystem. In this study, the dynamics of net primary productivity (NPP), evapotranspiration (ET), and water use efficiency (WUE) for arid ecosystems in Tianshan North Slope are explored by running the arid ecosystem model at 25 km resolution under RCP2.6, RCP4.5, and RCP8.5. The climate in Tianshan North Slope presents a wet-warming trend during 2006–2055 under each RCP scenario with temporal and spatial heterogeneity. In response to the changes in climate and CO2, the regional annual NPP and ET increased during 2006–2055 by a respectively maximum rate of 2.15 g C m−2 year−1 and 0.52 mm year−1 under RCP8.5. Both the NPP and ET share a similar temporal and spatial heterogeneity with climate change. Different vegetation types respond differently to the changes under different RCP scenarios with increasing WUE. Under each RCP, the non-phreatophyte, phreatophyte, and grass are more sensitive to the changes than in the others, and the broadleaf forest and cropland are less sensitive to the changes.
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Moore, Caitlin E., Tim Brown, Trevor F. Keenan, Remko A. Duursma, Albert I. J. M. van Dijk, Jason Beringer, Darius Culvenor et al. „Reviews and syntheses: Australian vegetation phenology: new insights from satellite remote sensing and digital repeat photography“. Biogeosciences 13, Nr. 17 (13.09.2016): 5085–102. http://dx.doi.org/10.5194/bg-13-5085-2016.
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Abstract. Phenology is the study of periodic biological occurrences and can provide important insights into the influence of climatic variability and change on ecosystems. Understanding Australia's vegetation phenology is a challenge due to its diverse range of ecosystems, from savannas and tropical rainforests to temperate eucalypt woodlands, semi-arid scrublands, and alpine grasslands. These ecosystems exhibit marked differences in seasonal patterns of canopy development and plant life-cycle events, much of which deviates from the predictable seasonal phenological pulse of temperate deciduous and boreal biomes. Many Australian ecosystems are subject to irregular events (i.e. drought, flooding, cyclones, and fire) that can alter ecosystem composition, structure, and functioning just as much as seasonal change. We show how satellite remote sensing and ground-based digital repeat photography (i.e. phenocams) can be used to improve understanding of phenology in Australian ecosystems. First, we examine temporal variation in phenology on the continental scale using the enhanced vegetation index (EVI), calculated from MODerate resolution Imaging Spectroradiometer (MODIS) data. Spatial gradients are revealed, ranging from regions with pronounced seasonality in canopy development (i.e. tropical savannas) to regions where seasonal variation is minimal (i.e. tropical rainforests) or high but irregular (i.e. arid ecosystems). Next, we use time series colour information extracted from phenocam imagery to illustrate a range of phenological signals in four contrasting Australian ecosystems. These include greening and senescing events in tropical savannas and temperate eucalypt understorey, as well as strong seasonal dynamics of individual trees in a seemingly static evergreen rainforest. We also demonstrate how phenology links with ecosystem gross primary productivity (from eddy covariance) and discuss why these processes are linked in some ecosystems but not others. We conclude that phenocams have the potential to greatly improve the current understanding of Australian ecosystems. To facilitate the sharing of this information, we have formed the Australian Phenocam Network (http://phenocam.org.au/).
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Fan, Xue, Xingming Hao, Haichao Hao, Jingjing Zhang und Yuanhang Li. „Comprehensive Assessment Indicator of Ecosystem Resilience in Central Asia“. Water 13, Nr. 2 (07.01.2021): 124. http://dx.doi.org/10.3390/w13020124.
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The ecosystems in the arid inland areas of Central Asia are fragile and severely degraded. Understanding and assessing ecosystem resilience is a challenge facing ecosystems. Based on the net primary productivity (NPP) data estimated by the CASA model, this study conducted a quantitative analysis of the ecosystem’s resilience and comprehensively reflected its resilience from multiple dimensions. Furthermore, a comprehensive resilience index was constructed. The result showed that plain oasis’s ecosystem resilience is the highest, followed by deserts and mountainous areas. From the perspective of vegetation types, the highest resilience is artificial vegetation and the lowest is forest. In warm deserts, the resilience is higher in shrubs and meadows and lower in grassland vegetation. High coverage and biomass are not the same as the strong adaptability of the ecosystem. Moderate and slightly inelastic areas mainly dominate the ecosystem resilience of the study area. The new method is easy to use. The evaluation result is reliable. It can quantitatively analyze the resilience latitude and recovery rate, a beneficial improvement to the current ecosystem resilience evaluation.
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Fan, Xue, Xingming Hao, Haichao Hao, Jingjing Zhang und Yuanhang Li. „Comprehensive Assessment Indicator of Ecosystem Resilience in Central Asia“. Water 13, Nr. 2 (07.01.2021): 124. http://dx.doi.org/10.3390/w13020124.
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The ecosystems in the arid inland areas of Central Asia are fragile and severely degraded. Understanding and assessing ecosystem resilience is a challenge facing ecosystems. Based on the net primary productivity (NPP) data estimated by the CASA model, this study conducted a quantitative analysis of the ecosystem’s resilience and comprehensively reflected its resilience from multiple dimensions. Furthermore, a comprehensive resilience index was constructed. The result showed that plain oasis’s ecosystem resilience is the highest, followed by deserts and mountainous areas. From the perspective of vegetation types, the highest resilience is artificial vegetation and the lowest is forest. In warm deserts, the resilience is higher in shrubs and meadows and lower in grassland vegetation. High coverage and biomass are not the same as the strong adaptability of the ecosystem. Moderate and slightly inelastic areas mainly dominate the ecosystem resilience of the study area. The new method is easy to use. The evaluation result is reliable. It can quantitatively analyze the resilience latitude and recovery rate, a beneficial improvement to the current ecosystem resilience evaluation.
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Novochadov, V. V., E. A. Ivantsova, A. A. Shiroky und N. V. Onistratenko. „Scenario model to forecast behavior of intrusive plant communities in response to control effects in arid agriculture“. IOP Conference Series: Earth and Environmental Science 843, Nr. 1 (01.11.2021): 012061. http://dx.doi.org/10.1088/1755-1315/843/1/012061.
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Abstract The presence of large areas of anthropogenic transformation of plant communities with a potentially negative impact on adjacent territories makes it relevant to develop various methods for automated monitoring and modeling of processes occurring in these ecosystems. Based on the results of previous studies of phytocoenoses, the authors selected four groups of indicators for constructing a scenario model: integral characteristics of intrusive plant communities (IPC), including those obtained by using remote dynamic methods; integral indicators of the negative impact of IPC on the adjacent agro-ecosystem; indicators of the distribution of mobile forms of trace elements in the soil; and indicators of soil microbiota. As the result, a hypothetical formula is obtained that allows, with minimal impact on the biosystem of technogenic IPC, to sufficiently reduce its adverse impact on the adjacent agro-ecosystem. Further refinement and dissemination of the scenario model and its connection to databases on plant communities will automatically change the values of the coefficients in the solving equations, thereby providing the most accurate and reliable forecast of the response of agro-ecosystems to various control actions.
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Salugin, A. N. „Simulation of degradation of pasture ecosystems of arid zone“. Rossiiskaia selskokhoziaistvennaia nauka, Nr. 2 (15.04.2023): 7–10. http://dx.doi.org/10.31857/s2500262723020023.
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New approaches to the study of succession dynamics are based on the original concept of system dynamics, which was used in the development of simulation models reflecting the dynamics of pasture ecosystems. The temporal dynamics of the soil and vegetation cover of the natural pastures of the Black Lands of Kalmykia reflects the degradation processes that are studied by simulation modeling. The processes of pasture degradation in the subarid belt of Southern Russia were described by ordinary differential equations. This concept is the basic one in the development of simulation models. The dynamics of changes in effective coatings for phytocenoses of pastures of Black Lands in the process of degradation was traced from the original pastures to complete desertification. Analytical solutions for various conditions of succession dynamics in the degradation of natural pasture lands are a convenient test for assessing the adequacy of simulation modeling. The initial time periods of space observations of effective coatings of phytocenoses were used to parametrize simulation models. The models are implemented in the AnyLogic simulation system. The model development process is based on visual programming using the graphical user interface. Information flows in the Anylogic environment are redistributed over time through a system of storage devices interconnected by an oriented graph of the model. A computational experiment demonstrating simulation results with different parameters was used for an indicative (qualitative) assessment of ecosystem sustainability. The results of analytical modeling using ordinary differential equations and simulation modeling showed a high identity. The study of the dynamics of pasture ecosystems using a variation experiment demonstrates the possibility of visual (cognitive) selection of the parameters of the model that determines the conditions of stationarity of pasture ecosystems. Studying the dynamics of successions of pasture phytocnoses by this method opens up new opportunities for solving problems of optimal use of biological resources and sustainability of pasture ecosystems.
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Kang, Le, Xingguo Han, Zhibin Zhang und Osbert Jianxin Sun. „Grassland ecosystems in China: review of current knowledge and research advancement“. Philosophical Transactions of the Royal Society B: Biological Sciences 362, Nr. 1482 (22.02.2007): 997–1008. http://dx.doi.org/10.1098/rstb.2007.2029.
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Grasslands are the dominant landscape in China, accounting for 40% of the national land area. Research concerning China's grassland ecosystems can be chronologically summarized into four periods: (i) pre-1950s, preliminary research and survey of grassland vegetation and plant species by Russians, Japanese and Western Europeans, (ii) 1950–1975, exploration and survey of vegetation, soils and topography as part of natural resource inventory programmes by regional and national institutions mainly led by the Chinese Academy of Sciences, (iii) 1976–1995, establishment of field stations for long-term ecological monitoring and studies of ecosystem processes, (iv) 1996–present, comprehensive studies of community dynamics and ecosystem function integrating multi-scale and multidisciplinary approaches and experimental manipulations. Major findings of scientific significance in China's grassland ecosystem research include: (i) improved knowledge on succession and biogeochemistry of the semi-arid and temperate grassland ecosystems, (ii) elucidation of life-history strategies and diapause characteristics of the native grasshopper species as one of the key grassland pests, and (iii) development of effective management strategies for controlling rodent pests in grassland ecosystems. Opportunities exist for using the natural grasslands in northern China as a model system to test ecosystem theories that so far have proven a challenge to ecologists worldwide.
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Wu, Dan, Wei Wei, Zongshan Li und Qindi Zhang. „Coupling Effects of Terracing and Vegetation on Soil Ecosystem Multifunctionality in the Loess Plateau, China“. Sustainability 15, Nr. 2 (16.01.2023): 1682. http://dx.doi.org/10.3390/su15021682.
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In semi-arid and arid terrestrial ecosystems, terracing and vegetation may improve soil conditions and enhance habitats. Considerable recent works have focused on evaluating how terracing and vegetation affect individual ecosystem function, but none of these evaluations included soil ecosystem multifunctionality (SEMF), which has a positive significance for optimizing soil ecosystem management. Based on the survey data of six different combinations of terracing and vegetation in the Chinese Loess Plateau, 15 functional indicators related to soil fertility, nutrient transformation/cycling, and water conservation were selected. The maximum conversion of the mean value method was employed to quantify SEMF. Concerning individual ecosystem services, the capacities of half-moon terraces-Pinus tabulaeformis (Ht-P. tabulaeformis) and level benches-Caragana korshinskii (Lb-C. korshinskii) to maintain soil fertility were 43.25% and 42.01% higher than those of counter-slope terraces-Platycladus orientalis (Ct-P. orientalis). On the contrary, Ct-P. orientalis showed better nutrient transformation and cycling services, which was 9.23% higher than those of Ht-P. tabulaeformis, therefore, we observed the highest SEMF in the Ht-P. tabulaeformis. Terracing, with a 29.2% explained variation, had a greater influence than that of vegetation (12.6%), while the coupling effect of terracing and vegetation (37.9%) was the most important factor that determined the SEMF. Thus, Ht-P. tabulaeformis and Lb-C. korshinskii should be promoted in the Loess Plateau area. The results of this study have significance in terms of understanding the interactions between terracing, vegetation, and soil ecosystems.
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Cheng, Kaili, Zhongmin Hu, Shenggong Li, Qun Guo, Yanbin Hao und Wenping Yuan. „Improvement of predicting ecosystem productivity by modifying carbon–water–nitrogen coupling processes in a temperate grassland“. Journal of Plant Ecology 14, Nr. 1 (09.11.2020): 10–21. http://dx.doi.org/10.1093/jpe/rtaa072.
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Abstract Aims Prediction of changes in ecosystem gross primary productivity (GPP) in response to climatic variability is a core mission in the field of global change ecology. However, it remains a big challenge for the model community to reproduce the interannual variation (IAV) of GPP in arid ecosystems. Accurate estimates of soil water content (SWC) and GPP sensitivity to SWC are the two most critical aspects for predicting the IAV of GPP in arid ecosystems. Methods We took a widely used model Biome-BGC as an example, to improve the model performances in a temperate grassland ecosystem. Firstly, we updated the estimation of SWC by modifying modules of evapotranspiration, SWC vertical profile and field capacity. Secondly, we modified the function of controlling water–nitrogen relation, which regulates the GPP–SWC sensitivity. Important Findings The original Biome-BGC overestimated the SWC and underestimated the IAV of GPP sensitivity, resulting in lower IAV of GPP than the observations, e.g. it largely underestimated the reduction of GPP in drought years. In comparison, the modified model accurately reproduced the observed seasonal and IAVs in SWC, especially in the surface layer. Simulated GPP–SWC sensitivity was also enhanced and became closer to the observations by optimizing parameter controlling nitrogen mineralization. Consequently, the model’s capability of reproducing IAV of GPP has been largely improved by the modifications. Our results demonstrate that SWC in the surface layer and the consequent effects on nitrogen availability should be among the first considerations for accurate modeling IAV of GPP in arid ecosystems.
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Li, Shuaishuai, Jiahua Zhang, Sha Zhang, Yun Bai, Dan Cao, Tiantian Cheng, Zhongtai Sun, Qi Liu und Til Prasad Pangali Sharma. „Impacts of Future Climate Changes on Spatio-Temporal Distribution of Terrestrial Ecosystems over China“. Sustainability 13, Nr. 6 (10.03.2021): 3049. http://dx.doi.org/10.3390/su13063049.
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Understanding the response of terrestrial ecosystems to future climate changes would substantially contribute to the scientific assessment of vegetation–climate interactions. Here, the spatiotemporal distribution and dynamics of vegetation in China were projected and compared based on comprehensive sequential classification system (CSCS) model under representative concentration pathway (RCP) RCP2.6, RCP4.5, and RCP8.5 scenarios, and five sensitivity levels were proposed. The results show that the CSCS model performs well in simulating vegetation distribution. The number of vegetation types would increase from 36 to 40. Frigid–perhumid rain tundra and alpine meadow are the most distributed vegetation types, with an area of more than 78.45 × 104 km2, whereas there are no climate conditions suitable for tropical–extra-arid tropical desert in China. Some plants would benefit from climate changes to a certain extent. Warm temperate–arid warm temperate zone semidesert would expand by more than 1.82% by the 2080s. A continuous expansion of more than 18.81 × 104 km2 and northward shift of more than 124.93 km in tropical forest would occur across all three scenarios. However, some ecosystems would experience inevitable changes. More than 1.33% of cool temperate–extra-arid temperate zone desert would continuously shrink. Five sensitivity levels present an interphase distribution. More extreme scenarios would result in wider ecosystem responses. The evolutionary trend from cold–arid vegetation to warm–wet vegetation is a prominent feature despite the variability in ecosystem responses to climate changes.
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Naikwade, Pratap. „Changes in Soil Carbon Sequestration during Woody Plant Encroachment in Arid Ecosystems“. Plantae Scientia 4, Nr. 4-5 (16.09.2021): 266–76. http://dx.doi.org/10.32439/ps.v4i4-5.266-276.
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Carbon sequestration is one of the most important and highly recommended measures for mitigating climate change. Soil organic carbon (SOC) has potential to sequester the largest amount of carbon (C) for the longest time period in the midst of the organic C sinks in terrestrial ecosystems of the earth. In recent years, apprehension of the role of soils as sink for carbon on a wide-ranging scale has become dynamic. From last 150 years, encroachment of trees and shrubs into grasslands and the ‘thicketization’ of savannas have been reported and is a global phenomenon. One possibly beneficial effect could be that the shrub and tree-dominated ecosystems will sequester more carbon and will be a buffer for elevated atmospheric carbon dioxide (CO2) levels. The question of what is impact of woody encroachment on soil carbon balance of an ecosystem has proved difficult to answer, and the results remain debatable. The magnitude and pattern of changes in the SOC with woody encroachment are exceedingly abstruse and varies from significant increases, to significant decreases to no net change in SOC. Impact of wood plant encroachment on carbon sequestration is discussed in this paper considering various studies with different results so it will lead to better understanding of the complex phenomenon. SOC sequestration is effective greenhouse gas mitigation strategy and a vital ecosystem service. Increasing SOC may helpful to mitigate negative effects of growing concentration of CO2 in atmosphere and may be advantageous in decelerating or reversal in global climate change rate.
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Naikwade, P. V. „Changes in Soil Carbon Sequestration during Woody Plant Encroachment in Arid Ecosystems“. Plantae Scientia 4, Nr. 5 (16.09.2021): 266–76. http://dx.doi.org/10.32439/ps.v4i5.266-276.
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Carbon sequestration is one of the most important and highly recommended measures for mitigating climate change. Soil organic carbon (SOC) has potential to sequester the largest amount of carbon (C) for the longest time period in the midst of the organic C sinks in terrestrial ecosystems of the earth. In recent years, apprehension of the role of soils as sink for carbon on a wide-ranging scale has become dynamic. From last 150 years, encroachment of trees and shrubs into grasslands and the ‘thicketization’ of savannas have been reported and is a global phenomenon. One possibly beneficial effect could be that the shrub and tree-dominated ecosystems will sequester more carbon and will be a buffer for elevated atmospheric carbon dioxide (CO2) levels. The question of what is impact of woody encroachment on soil carbon balance of an ecosystem has proved difficult to answer, and the results remain debatable. The magnitude and pattern of changes in the SOC with woody encroachment are exceedingly abstruse and varies from significant increases, to significant decreases to no net change in SOC. Impact of wood plant encroachment on carbon sequestration is discussed in this paper considering various studies with different results so it will lead to better understanding of the complex phenomenon. SOC sequestration is effective greenhouse gas mitigation strategy and a vital ecosystem service. Increasing SOC may helpful to mitigate negative effects of growing concentration of CO2 in atmosphere and may be advantageous in decelerating or reversal in global climate change rate.
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Kulik, K. N., A. N. Salugin und E. A. Sidorova. „Dynamic stability of arid ecosystems“. Arid Ecosystems 2, Nr. 2 (April 2012): 86–90. http://dx.doi.org/10.1134/s2079096112020047.
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LAL JAKHAR, BHANWAR, AS BALODA, MD CHOUDHARY, KK SAINI, ML JAKHAR und T. YADAV. „Biodiversity of white grub, (Coleoptera: Scaraeidae) in semi arid agro-ecosystem of Rajasthan“. Journal of AgriSearch 8, Nr. 2 (30.06.2021): 112–16. http://dx.doi.org/10.21921/jas.v8i2.7293.
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White grubs are the major insect pests of cultivated plants in semi arid agro-ecosystem of Rajasthan. It is important to understand diversity, abundance and distribution of scarabaeid beetles for planning effective pest management programme. The experimental data were collected from nine locations in three different ecosystems in Kharif season of year 2019. Species identification revealed that there was total nine species were recorded from 18885 specimens collected. The identified species were belongs under two subfamilies of Scarabaeidae family. Maximum specimens were collected in the month of July from selected sites. When species diversity was compared among different locations, it was found that Shannon Wiener diversity index varied from 1.235 to 1.095, which indicates that species were less diverse but frequently present. The present study can be used to formulate the integrated pest management strategies based on most abundance and diverse scarabaeids in semi-arid agro-ecosystem of Rajasthan.
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Bukvareva, Elena N., Karsten Grunewald, Oxana Klimanova, Evgeni Kolbovsky, Andrey Shcherbakov, Tatiana Sviridova und Dmitry Zamolodchikov. „TEEB-Russia: Towards National Ecosystem Accounting“. Sustainability 13, Nr. 12 (11.06.2021): 6678. http://dx.doi.org/10.3390/su13126678.
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Russia’s ecosystems and ecosystem services (ES) are critical not only for the country’s economy and well-being of the people but also for maintaining biodiversity and biosphere regulation around the world. Thus, the introduction of ecosystem accounting in Russia is an urgent national and international goal to which the TEEB-Russia project is dedicated. In this publication, we briefly review and discuss the main project results. Based on currently available open statistical and cartographic data, TEEB-Russia project conducted the first national assessment of terrestrial ES in Russia to derive methodological approaches to national ecosystem accounting. A range of indicators were used to assess the ES provided by ecosystems (potential) as well as the level of demand and consumption of ES by Russia’s regions, both for populations and economies. Indicators of ecosystem assets include extent (ecosystem size) and condition (productivity, phytomass, bird and plant species diversity). An analysis of the correlations between indicators of ES and ecosystem assets showed that a system of national ecosystem accounting in Russia should be regionally differentiated to take account of the strong heterogeneity of natural conditions and the socio-economic development at this level. Decision-making in spatial planning and ecosystem management should carefully consider the difference between causal relationships between indicators and correlations that arise from the simultaneous response of indicators to changes in other factors. Differences in relationships between indicators at different spatial scales should also be taken into account.
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Burova, Aleksandra Yu. „Digital Ecosystems: The Need and Content of Regulation“. Journal of Russian Law 28, Nr. 1 (2024): 143. http://dx.doi.org/10.61205/jrp.2024.1.7.
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The article deals with the issue of legislative regulation of digital ecosystems. In modern Russia, there are several large digital ecosystems that play a significant role in bringing a product to the end consumer, and therefore there is a need for legislative regulation of relevant relations. The purpose of the work is to identify the directions and approximate content of legislative regulation of digital ecosystems. Research objectives: to identify the range of relationships those arise in the digital ecosystem; to identify the problems inherent in each group of relationships; to establish the position of the current legislation on the identified problems. General scientific methods were used in the course of the study. In order to determine the subject composition of the digital ecosystem, logical methods of analysis and synthesis were used. Using a systematic method, groups of relationships that develop within the framework of digital ecosystems are established. Private law methods made it possible to identify gaps in legislation and determine the sufficiency of current regulation (the formal legal method), as well as to identify directions and optimal vectors of development of legislation for regulating digital ecosystems (the method of legal modeling). According to the results of the study, six groups of relationships are identified, depending on the composition of the participants in the digital ecosystem. Each group identifies several main problems that require at least minimal legislative regulation. The vectors of the approximate content of this regulation are indicated. It is noted that some of these issues are typical not only for ecosystems, but also for services that are not. At the same time, there are problems that are relevant only for digital ecosystems. Therefore, the adoption of a single legislative act is impractical, and regulation should be integrated into existing regulations. Local regulations — the rules of digital platform operators — should be used more actively in regulation. At the same time, it is possible to develop uniform rules for the digital ecosystem.
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Zhu, Tianyu, Chengzhi Li, Xiaocao Liu und Xiaobing Zhao. „Assessing Ecological Restoration in Arid Mining Regions: A Progressive Evaluation System“. Sustainability 16, Nr. 6 (08.03.2024): 2266. http://dx.doi.org/10.3390/su16062266.
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The mining activities in arid regions have resulted in significant ecological environmental issues, exacerbating the already challenging ecological conditions and leading to severe ecosystem damage. Merely relying on natural recovery processes proves inadequate, thus necessitating the implementation of artificial restoration measures to facilitate ecosystem recovery in these arid mining regions. However, it is difficult to scientifically answer the questions of how artificial restoration can be effectively combined with natural recovery, and to what extent can artificial assistance can define the beginning of natural recovery in ecosystems. To address this issue, this study proposed a stepwise ecological restoration model for arid mining regions. The model delineated the ecological restoration process in arid mining regions into three phases: “artificial reconstruction”, “auxiliary ecological restoration”, and “natural recovery”, and constructed an evaluation index system of the stepwise ecological restoration process. Taking an example of a mining ecological restoration in Aksu, Xinjiang, this study examined the evaluation effects of the stepwise ecological restoration model on ecological restoration projects in arid mining regions. The research showed that adopting the stepwise ecological restoration model in arid mining regions can achieve scientific and moderate artificial restoration, better clarify ecological restoration goals, and facilitate the implementation of ecological restoration projects.
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Thayer, Vargas, Castellanos, Lafon, McCarl, Roelke, Winemiller und Lacher. „Integrating Agriculture and Ecosystems to Find Suitable Adaptations to Climate Change“. Climate 8, Nr. 1 (09.01.2020): 10. http://dx.doi.org/10.3390/cli8010010.
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Climate change is altering agricultural production and ecosystems around the world. Future projections indicate that additional change is expected in the coming decades, forcing individuals and communities to respond and adapt. Current research efforts typically examine climate change effects and possible adaptations but fail to integrate agriculture and ecosystems. This failure to jointly consider these systems and associated externalities may underestimate climate change impacts or cause adaptation implementation surprises, such as causing adaptation status of some groups or ecosystems to be worsened. This work describes and motivates reasons why ecosystems and agriculture adaptation require an integrated analytical approach. Synthesis of current literature and examples from Texas are used to explain concepts and current challenges. Texas is chosen because of its high agricultural output that is produced in close interrelationship with the surrounding semi-arid ecosystem. We conclude that future effect and adaptation analyses would be wise to jointly consider ecosystems and agriculture. Existing paradigms and useful methodology can be transplanted from the sustainable agriculture and ecosystem service literature to explore alternatives for climate adaptation and incentivization of private agriculturalists and consumers. Researchers are encouraged to adopt integrated modeling as a means to avoid implementation challenges and surprises when formulating and implementing adaptation.
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Liu, Yu, und David Sumpter. „Insights into resource consumption, cross-feeding, system collapse, stability and biodiversity from an artificial ecosystem“. Journal of The Royal Society Interface 14, Nr. 126 (Januar 2017): 20160816. http://dx.doi.org/10.1098/rsif.2016.0816.
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Community ecosystems at very different levels of biological organization often have similar properties. Coexistence of multiple species, cross-feeding, biodiversity and fluctuating population dynamics are just a few of the properties that arise in a range of ecological settings. Here we develop a bottom-up model of consumer–resource interactions, in the form of an artificial ecosystem ‘number soup’, which reflects basic properties of many bacterial and other community ecologies. We demonstrate four key properties of the number soup model: (i) communities self-organize so that all available resources are fully consumed; (ii) reciprocal cross-feeding is a common evolutionary outcome, which evolves in a number of stages, and many transitional species are involved; (iii) the evolved ecosystems are often ‘robust yet fragile’, with keystone species required to prevent the whole system from collapsing; (iv) non-equilibrium dynamics and chaotic patterns are general properties, readily generating rich biodiversity. These properties have been observed in empirical ecosystems, ranging from bacteria to rainforests. Establishing similar properties in an evolutionary model as simple as the number soup suggests that these four properties are ubiquitous features of all community ecosystems, and raises questions about how we interpret ecosystem structure in the context of natural selection.
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Ranjbar, Abolfazl, Marzieh Taabe, Seiied Hojjat Mousavi und Mohammad Khosroshahi. „Quantifying the Vegetation Health Based on the Resilience in an Arid System“. Ekológia (Bratislava) 37, Nr. 1 (01.03.2018): 32–41. http://dx.doi.org/10.2478/eko-2018-0004.
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AbstractProper management of natural ecosystems is not possible without the knowledge of the health status of its components. Vegetation, as the main component of the ecosystem, plays an important role in its health. One of the key determinants of vegetation health is its resilience in the face of environmental disorders. This research was conducted in parts of the Namakzar-e Khaf watershed in Northeast of South Khorasan Province with the aim of quantifying the vegetative resilience on behalf of the ecosystem health in response to long-term precipitation changes. First, the annual precipitation standardization was performed during a thirty-year period by the SPI method. Then, the average variation in TNDVI index obtained from the Landsat satellite images was examined and the resilience was tested by calculating the four effective factors (amplitude, malleability, damping and hysteresis). According to the results, the amplitude in the survey period was 6.04% and the vegetation has had different values of damping over the years. The most prominent example of vegetation resilience occurred between 1986 and 1996, with malleability of 0.7 and damping of zero. Vegetation in this period, after the elimination of drought effects (1986), has not only returned to the amount of vegetation of reference year with severe precipitation (1996) but also increased by 0.25%. This increase, as the index of hysteresis, has been presented for the first time in the ecosystem health discussion quantitatively in the present study. A set of quantitative calculations showed that despite reduced annual precipitation and drought events, the vegetation has been able to maintain its resilience, which indicates the health of vegetation in the studied ecosystem.
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Zou, Jie, Jianli Ding, Martin Welp, Shuai Huang und Bohua Liu. „Assessing the Response of Ecosystem Water Use Efficiency to Drought During and after Drought Events across Central Asia“. Sensors 20, Nr. 3 (21.01.2020): 581. http://dx.doi.org/10.3390/s20030581.
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The frequency and intensity of drought are expected to increase worldwide in the future. However, it is still unclear how ecosystems respond to drought. Ecosystem water use efficiency (WUE) is an essential ecological index used to measure the global carbon–water cycles, and is defined as the carbon absorbed per unit of water lost by the ecosystem. In this study, we applied gross primary productivity (GPP), evapotranspiration (ET), land surface temperature (LST), and normalized difference vegetation index (NDVI) data to calculate the WUE and drought index (temperature vegetation dryness index (TVDI)), all of which were retrieved from moderate resolution imaging spectroradiometer (MODIS) data. We compared the mean WUE across different vegetation types, drought classifications, and countries. The temporal and spatial changes in WUE and drought were analyzed. The correlation between drought and WUE was calculated and compared across different vegetation types, and the differences in WUE between drought and post-drought periods were compared. The results showed that (1) ecosystems with a low (high) productivity had a high (low) WUE, and the mean ecosystem WUE of Central Asia showed vast differences across various drought levels, countries, and vegetation types. (2) The WUE in Central Asia exhibited an increasing trend from 2000 to 2014, and Central Asia experienced both drought (from 2000 to 2010) and post-drought (from 2011 to 2014) periods. (3) The WUE showed a negative correlation with drought during the drought period, and an obvious drought legacy effect was found, in which severe drought affected the ecosystem WUE over the following two years, while a positive correlation between WUE and drought was found in the post-drought period. (4) A significant increase in ecosystem WUE was found after drought, which revealed that arid ecosystems exhibit high resilience to drought stress. Our results can provide a specific reference for understanding how ecosystems will respond to climate change.