Global Change Factors Research Articles

Dual closed-loop chemical recycling support sustainable mitigation of plastic pollution

Recently, the Feringa Nobel Prize Scientist Joint Research Center demonstrated a green method to synthesize plastics from natural small thioctic acid (TA) monomers. This novel recycling system provides successful chemical recycling using a dual closed-loop process under mild operating conditions. Here, we discuss the critical environmental sustainability dynamics of these recycling systems and their potential to support a plastic circular economy.

Combined effect of microplastics and global warming factors on early growth and development of the sea urchin (Paracentrotus lividus)

The aim of this work was to estimate the potential risk of the combined effect of global change factors (acidification, temperature increase) and microplastic (MP) pollution on the growth and development of the sea urchin P. lividus. Embryo-larval bioassays were conducted to determine growth and morphology after 48 h of incubation with MP (1000 and 3000 particles/mL); with filtered sea water at pH = 7.6; and with their combinations. A second experiment was conducted to study the effect of pH and MP in combination with a temperature increase of 4 °C compared to control (20 °C). We found that the inhibition of growth in embryos reared at pH = 7.6 was around 75%. Larvae incubated at 3000 MP particles/mL showed a 20% decrease in growth compared to controls. The exposure to MP also induced an increase in the postoral arm separation or rounded vertices. The combined exposure to a pH 7.6 and MP caused a significant decrease of larval growth compared to control, to MP and to pH 7.6 treatments. Morphological alterations were observed in these treatments, including the development of only two arms. Increasing the temperature resulted in an increased growth in control, in pH 7.6 and pH 7.6 + MP3000 treatments, but the relative stomach volume decreased. However, when growth parameters were expressed per Degree-Days the lower growth provoked by the thermal stress was evidenced in all treatments. In this work we demonstrated that MP could aggravate the effect of a decreased pH and that an increase in water temperature generated an additional stress on P. lividus larvae, manifested in a lower growth and an altered development. Therefore, the combined stress caused by ocean warming, ocean acidification, and microplastic pollution, could threaten sea urchin populations leading to a potential impact on coastal ecosystems.

Responses of stomatal features and photosynthesis to porewater N enrichment and elevated atmospheric CO2inPhragmites australis, the common reed

Biological invasions increasingly threaten native biodiversity and ecosystem services. One notable example is the common reed, Phragmites australis, which aggressively invades North American salt marshes. Elevated atmospheric CO2 and nitrogen pollution enhance its growth and facilitate invasion because P. australis responds more strongly to these enrichments than do native species. We investigated how modifications to stomatal features contribute to strong photosynthetic responses to CO2 and nitrogen enrichment in P. australis by evaluating stomatal shifts under experimental conditions and relating them to maximal stomatal conductance (gwmax ) and photosynthetic rates. Plants were grown in situ in open-top chambers under ambient and elevated atmospheric CO2 (eCO2 ) and porewater nitrogen (Nenr ) in a Chesapeake Bay tidal marsh. We measured light-saturated carbon assimilation rates (Asat ) and stomatal characteristics, from which we calculated gwmax and determined whether CO2 and Nenr altered the relationship between gwmax and Asat . eCO2 and Nenr enhanced both gwmax and Asat , but to differing degrees; gwmax was more strongly influenced by Nenr through increases in stomatal density while Asat was more strongly stimulated by eCO2 . There was a positive relationship between gwmax and Asat that was not modified by eCO2 or Nenr , individually or in combination. Changes in stomatal features co-occur with previously described responses of P. australis to eCO2 and Nenr . Complementary responses of stomatal length and density to these global change factors may facilitate greater stomatal conductance and carbon gain, contributing to the invasiveness of the introduced lineage.

An analysis of land-use change (1995-2015) in Gorakhpur district, Uttar Pradesh

Land plays a key role in the determination of human economic activities as well as one’s social, cultural and political progress. All agricultural activities, animal husbandry, forestry, cereal productions etc. depends on the quality and productivity of the land. The entire terrestrial eco-system which comprises soil, water, air, plants and minerals survive on land resource. It helps to meet the demands for food, energy and needs of human livelihoods. Land use, precisely, refers to the sectoral utilization of a unit of available land in a given time. The proper utilization of the land enables economic development in a region. However, land-use changes are increasingly recognized as major factors of global environmental change. Land utilization analysis is needed to generate a general framework of strategic and effective management and an understanding of the characteristics of the land. This study analyses the changes in land use pattern recorded over two decades (from 1995 to 2015) in the Gorakhpur district of Uttar Pradesh. The study goes on to find that positive growth has been recorded in the unproductive land use categories and negative growth in the productive ones due to uncontrolled and haphazard anthropogenic practices. Productive land use such as net sown area (7.02%), forest area (1.31%), area under the bush forest & garden (0.36 %) and pasture (0.02 %) increased whereas unproductive land use such as barren cultivable wasteland (0.44%), present fallow land (4.12%), area put to non-agricultural use (2.09%) increased during two decades.

Nitrogen availability modulates the impacts of plant invasion on the chemical composition of soil organic matter

Plant invasion can dramatically impact soil carbon (C) cycling and sequestration while, other global change factors, such as nitrogen (N) deposition, are predicted to promote plant invasion. However, questions remain as to whether the chemical composition of soil organic C (SOC) may alter with plant invasion and how N availability modulates the invasion effects on SOC. In this study, we conducted a 10-year mesocosm experiment simulating the invasion of Japanese knotweed (Polygonum cuspidatum) into a fallow soil, coupled with a simultaneous mineral fertilizer application scheme for the invasive plants. We investigated the invasion effects on the chemical composition of various SOC components at the molecular level, and examined how these effects responded to changes in soil N availability. Compared with the noninvaded soils, the knotweed-invaded soils exhibited a 17% increase in the microbial-derived C, mainly through the accumulation of fungal residue in the form of amino sugars. Despite receiving leaf litter which was abundant in polyphenolic compounds (40% and 3-times higher in lignin and tannins per unit biomass, respectively), the knotweed-invaded soils did not differ in the concentration of plant lipids and lignin monomers compared to the noninvaded soils inhabited by grasses. However, the concentrations of phytosterol in the knotweed-invaded soils were 1.5-fold as that in the noninvaded soils. Fertilizer application significantly increased the retention of plant-derived compounds in the knotweed-invaded soils, but also induced 45% greater degradation of lignin. Moreover, under fertilizer application, the knotweed-invaded soils accumulated 46% more microbial-derived C, primarily due to the altered microbial biomass and community composition. Collectively, our findings suggest that plant invasion has the potential to influence SOC chemical composition through changes in plant-derived and microbial-derived C. Furthermore, N deposition could reinforce the invasion effects on the molecular composition and accrual of SOC. Our results also highlight the need to understand the impacts of biological invasion in the context of other global change drivers that both affect invasion and modulate their effects.

The canopy layer, a biogeochemical actor in the forest N-cycle

Atmospheric nitrogen (N) depositions have increased sharply since the industrial revolution. Numerous authors forecasted severe impacts on forest ecosystem services and functioning when new N input exceeds both biotic and abiotic holding capacity, in what is known as the N saturation process. However, most of the studies performed so far to quantify these impacts have largely neglected the potential role of the canopy and associated biota in biogeochemical processes. The present review collects and summarizes the existing literature about all the interactions of atmospheric N deposition and the canopy, evidencing different processes that may interfere with them. By summarizing the research of the last three decades, we found that a share of both wet and dry N deposition can be retained within the canopy, partially absorbed by the leaves or other aerial parts and utilized for plant metabolism, substantially changing the fate of N in the ecosystem. Focusing on canopy-associated biota, we analyzed how this compartment can represent a highly reactive layer and have an active role in different processes involved in the N cycle such as nitrification, fixation and volatilization. It emerges clearly that the canopy hosts a complex network of processes; however, despite this, most of the manipulative experiments failed to include the canopy into the studies. The documented manipulative experiments which included the canopy are mainly short-term and represent very few forest types. Moreover, we highlighted a lack of research concerning the interaction between the complex network of canopy processes, atmospheric N deposition and other global change factors, such as increasing atmospheric CO2 concentration, increasing temperature and drought events.

Effects of microplastics and drought on soil ecosystem functions and multifunctionality

Abstract Microplastics in soils have become an important threat for terrestrial systems as they may potentially alter the geochemical/biophysical soil environment and can interact with drought. As microplastics may affect soil water content, this could exacerbate the well‐known negative effects of drought on ecosystem functionality. Thus, functions including litter decomposition, soil aggregation or those related with nutrient cycling can be altered. Despite this potential interaction, we know relatively little about how microplastics, under different soil water conditions, affect ecosystem functions and multifunctionality. To address this gap, we performed an experiment using grassland plant communities growing in microcosms. Microplastic fibres (absent, present) and soil water conditions (well‐watered, drought) were applied in a fully factorial design. At harvest, we measured soil ecosystem functions related to nutrient cycling (β‐glucosaminidase, β‐D‐cellobiosidase, phosphatase, β‐glucosidase enzymes), respiration, nutrient retention, pH, litter decomposition and soil aggregation (water stable aggregates). As terrestrial systems provide these functions simultaneously, we also assessed ecosystem multifunctionality, an index that encompasses the array of ecosystem functions measured here. We found that the interaction between microplastic fibres and drought affected ecosystem functions and multifunctionality. Drought had negatively affected nutrient cycling by decreasing enzymatic activities by up to ~39%, while microplastics increased soil aggregation by ~18%, soil pH by ~4% and nutrient retention by up to ~70% by diminishing nutrient leaching. Microplastic fibres also impacted soil enzymes, respiration and ecosystem multifunctionality, but importantly, the direction of these effects depended on soil water status. That is, under well‐watered conditions, these functions decreased with microplastic fibres by up to ~34% while under drought they had similar values irrespective of the microplastic presence, or tended to increase with microplastics. Litter decomposition had a contrary pattern increasing with microplastics by ~6% under well‐watered conditions while decreasing to a similar percentage under drought. Synthesis and applications. Single ecosystem functions can be positively or negatively affected by microplastics fibres depending on soil water status. However, our results suggest that microplastic fibres may cause negative effects on ecosystem soil multifunctionality of a similar magnitude as drought. Thus, strategies to counteract this new global change factor are necessary.

Potential Effects of Microplastic on Arbuscular Mycorrhizal Fungi.

Microplastics (MPs) are ubiquitously found in terrestrial ecosystems and are increasingly recognized as a factor of global change (GCF). Current research shows that MP can alter plant growth, soil inherent properties, and the composition and activity of microbial communities. However, knowledge about how microplastic affects arbuscular mycorrhizal fungi (AMF) is scarce. For plants it has been shown that microplastic can both increase and decrease the aboveground biomass and reduce the root diameter, which could indirectly cause a change in AMF abundance and activity. One of the main direct effects of microplastic is the reduction of the soil bulk density, which translates to an altered soil pore structure and water transport. Moreover, especially fibers can have considerable impacts on soil structure, namely the size distribution and stability of soil aggregates. Therefore, microplastic alters a number of soil parameters that determine habitat space and conditions for AMF. We expect that this will influence functions mediated by AMF, such as soil aggregation, water and nutrient transport. We discuss how the impacts of microplastic on AMF could alter how plants deal with other GCFs in the context of sustainable food production. The co-occurrence of several GCFs, e.g., elevated temperature, drought, pesticides, and microplastic could modify the impact of microplastic on AMF. Furthermore, the ubiquitous presence of microplastic also relates to earth system processes, e.g., net primary production (NPP), carbon and nitrogen cycling, which involve AMF as key soil organisms. For future research, we outline which experiments should be prioritized.

Divergent effects of drought and nitrogen deposition on microbial and arthropod soil communities in a Mediterranean forest

Drivers of global change such as warming and increased nitrogen (N) availability are altering soil communities worldwide, with unknown consequences for the functioning of the terrestrial ecosystems. Higher N availability may stimulate soil communities and boost nutrient cycling, but the expected increase in aridity may nullify this effect. Additionally, shifts in microbial communities may lead to trophic cascades throughout soil food webs, affecting key ecosystem properties associated with the turnover of carbon and nutrients. Whether the responses to these different drivers of global change are similar between the main guilds of soil organisms, however, is unclear. We analyzed soil phospholipid fatty acids and extracted soil fauna to determine the simultaneous responses of microbial and arthropod soil communities to experimental drought and increased N availability in a Mediterranean forest. The experimental drought decreased community sizes across the entire soil food web, and N addition increased the biomass of all microbial groups except fungi, thereby increasing the relative dominance of bacteria. Likewise, the abundance of oribatid mites strongly increased after the addition of N, whereas the population of springtails quickly decreased, leading to a shift in the structure of the arthropod community. An increase in soil N availability promoted the energy channel dominated by bacteria, triggering a bottom-up trophic cascade affecting the arthropod mesofauna, thus propagating the effects of N inputs throughout the soil food web. The strong constraint of drought on soil microbes, however, may neutralize the effect of an increase in N availability. Complex interactions among factors of global change may therefore hinder our ability to predict their effects on soil biodiversity and associated consequences for ecosystem functioning. Forecasts of responses of soil biodiversity to global change should not only consider different drivers and their potential interactions, but also the likely contrasting effects among different groups of soil organisms.

Long-term nitrogen addition and precipitation reduction decrease soil nematode community diversity in a temperate forest

Terrestrial ecosystems are driven by different global change factors, such as atmospheric nitrogen deposition and precipitation reduction. Nitrogen deposition and precipitation reduction have a great impact on the above- and underground processes. Most previous studies mainly focused on the effects of nitrogen deposition and/or precipitation reduction on aboveground processes, while the effects on underground processes were relatively scarce. As an important part of the underground soil food web, soil nematode community occupies different nutritional niches and is sensitive to external disturbances, and it is often used as indicator for studying underground processes. However, we know little about the response of soil nematode community to nitrogen deposition and/or precipitation reduction. Here, we used a 10-year of factorial manipulation by applying nitrogen solution and reducing the amount of precipitation to the soil, and to investigate the responses of soil nematode community to nitrogen deposition and/or precipitation reduction in a temperate forest. We expected that nitrogen addition could promote while precipitation inhibited the activity of soil nematode community. Furthermore, we expected nitrogen addition and precipitation could have interactive effect on soil nematode community. Our results found that nitrogen addition and/or precipitation reduction treatment caused significant changes in the composition of soil nematode community. Nitrogen addition and nitrogen addition combined with precipitation reduction induced negative effects and significantly decreased the abundance and diversity of soil nematode community, while precipitation reduction only decreased the abundance of soil nematode community. Nitrogen addition and precipitation reduction had synergistic effect on soil nematode community with higher trophic levels. Compared with precipitation reduction treatment, the negative effect of nitrogen addition on soil nematode community was more severe. According to the structural equation model (SEM), we found that nitrogen addition and precipitation reduction could affect the abundance of soil nematode community by affecting the plant richness and soil pH. Since the decrease of enrichment index (EI) and the increase of structure index (SI), our research results revealed that nitrogen addition could lead to soil food web in a lower nutrients available condition.

Alien birds in Argentina: pathways, characteristics and ecological roles

Currently, there is a consensus that biological invasions are one of the most important factors in global change due to their ability to modify structures and functions of many communities. The aim of this work was to provide an exhaustive assessment of the alien birds of Argentina, their routes of entry, impacts, and a synthesis of their attributes. We reviewed and compiled data from a variety of sources and databases on alien birds in Argentina and provide a summary for ten species that had been introduced. Introductions occurred in two peaks, one at the end of the nineteenth century and the other during the 1990s. Most of species entered through the Pampas, Espinal, Bosque and Estepas Patagonica ecoregions between 34° and 50° south. Reasons for these introductions include game birds (Silver Pheasant Lophura nycthemera, California Quail Callipepla californica), domestic consumption (Mallard Anas platyrhynchos, Graylag Goose Anser anser, Rock pigeon Columba livia), pets (European Greenfinch Chloris chloris, European Goldfinch Carduelis carduelis, European Starling Sturnus vulgaris, Crested Myna Acridotheres cristatellus, House Sparrow Passer domesticus). These species occupy ecoregions similar to those of their origins, however most have experienced an expansion in the range of ecological conditions within their new habitats. These species provide opportunity for understanding the dynamics of invasions since they provide a diversity in their ecology and environmental needs.

A Planetary Perspective of Earth Systems Sustainability: Reframing Climate Change Implications from Agricultural Adaptations in Maya Milpa Farming Communities in Belize

In a case review of climate-smart agriculture practices in Mayan milpa farming communities in Belize (Central America), this pa- per reframes how small-scale agriculture practices can influence larger Earth systems sustainability. In what has been a sustainable form of farming for hundreds of years, the milpa has become less sustainable due to global climate change, forest loss, soil degradation, population growth, and other factors. This article reviews the findings of a 2020 study of positive socio-ecological systems (SES) influences —environmental, economic, socio-cultural, and technological— from climate-smart practices on local resource sustainability. SES considers several multidisciplinary linkages of human and ecological factors in the agroecological system. SES considers several multidisciplinary linkages of human and ecological factors in the agroecological system. SES influences from small-scale climate-smart agriculture (CSA) practices can have both micro-scale impacts as well as macro-scale implications for SES sustainability and food security. Understanding the implications of small-scale farming on larger Earth systems can inform global climate change mitigations and government policy and action needed to promote CSA practices. This is important for the resilience of vulnerable populations such as Belizean milpa farming communities and others who rely directly on resource sustainability for their food and livelihood security.

滨海湿地生态系统土壤微生物及其影响因素研究综述

PDF HTML阅读 XML下载 导出引用 引用提醒 滨海湿地生态系统土壤微生物及其影响因素研究综述 DOI: 10.5846/stxb201909201961 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（41230751）；自然资源部公益性行业科研专项（201511086）；浙江省自然科学基金项目（LY19D010007）；自然资源部海岸带开发与保护重点实验室开放课题（2019CZEPK09） Progress and prospect of soil microorganisms and their influencing factors in coastal wetland ecosystem Author: Affiliation: Fund Project: [Foundation: National Natural Science Foundation of China (41230751); Special Funds for Public Industry Research Projects of the Ministry of Natural Resources(201511086); Natural Science Foundation of Zhejiang Province (LY19D010007)] 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:土壤微生物是滨海湿地生态系统中不可或缺的关键组分，在土壤发育、物质循环和污染物净化等诸多土壤生态过程中发挥着重要作用，对滨海湿地生态系统的维持与健康具有重大影响。系统梳理了滨海湿地土壤微生物群落结构特征和多样性，综述了土壤理化性质、植被状况、水文因素、生物入侵、全球变化、湿地开垦、石油污染等因素对滨海湿地土壤微生物的影响。在此基础上，对今后的研究重点提出了4个方面的展望：①加强全球变化多因子交互作用下滨海湿地土壤微生物的响应机制；②强化滨海湿地土壤微生物与环境因子的互作机理；③深化滨海湿地水动力条件对土壤微生物的影响机制；④开展土壤微生物与滨海湿地生态系统物质循环综合研究。研究以期为滨海湿地生态系统的保护和修复提供参考。 Abstract:As an indispensable component in coastal wetland ecosystem, soil microorganisms play an important role in many soil ecological processes, such as soil development, material circulation and pollutant purification, and have a significant impact on the maintenance and health of coastal wetland ecosystems. In this paper, the structure and diversity of soil microbial community in coastal wetlands were systematically reviewed, and the effect of influencing factors such as soil physicochemical properties, vegetation status, hydrological status, biological invasion, global change, wetland reclamation, and oil pollution on soil microorganisms in coastal wetlands were summarized. On this basis, four perspectives are proposed for the future research: 1) strengthening the response mechanism of soil microorganisms in coastal wetland under the interaction of multiple factors of global change; 2) strengthening the interaction mechanism of soil microorganisms and environmental factors in coastal wetland; 3) deepening the influence mechanism of hydrodynamic conditions on soil microorganisms in coastal wetland; and 4) carrying out the comprehensive research on soil microorganisms and material circulation of coastal wetland ecosystem. This study is expected to provide reference for the protection and restoration of coastal wetland ecosystems. 参考文献 相似文献 引证文献

氮沉降背景下土壤微生物对入侵植物乌桕叶绿素荧光特征的影响

植物入侵会造成入侵地生态系统功能和稳定性的破坏。与原产地种源相比，入侵种源植物在生理学特性方面有所不同，使其在资源利用和抵抗环境胁迫具有较强的竞争优势。叶绿素荧光特性与植物光合作用效率密切相关，对植物生长具有重要作用。氮沉降加剧是全球变化的一个重要因子，土壤微生物对植物吸收利用土壤养分至关重要。通过施用细菌抑制剂（链霉素）和真菌抑制剂（扑海因）选择性抑制的土壤微生物活性，开展乌桕盆栽实验，在模拟氮沉降背景下，研究不同微生物群落如何影响入侵乌桕叶绿素荧光特性，有助于理解入侵植物的进化特征和入侵机制，为有效防控入侵植物并降低其对生态系统危害提供理论依据。以原产地地和入侵地两个种源乌桕（Triadica sebifera）为研究对象，在氮沉降条件下，通过调控土壤细菌和真菌，探讨两个种源乌桕叶绿素荧光参数差异。结果显示：氮沉降显著增加乌桕相对叶绿素含量（SPAD）、光系统II的最大量子产率（F_v/F_m）、非光化学猝灭（NPQ）和半饱和光强（I_k）。入侵种源乌桕比原产地具有较低SPAD。氮沉降与细菌抑制剂共同作用显著增强了F_v/F_m、NPQ和I_k，显著减弱了光能利用率（α）和SPAD。细菌抑制剂减缓了本地种源乌桕α，真菌抑制剂促进本地种源乌桕I_k，抑制入侵种源乌桕I_k，细菌和真菌抑制剂可显著降低原产地乌桕α。氮沉降与生物抑制剂可显著作用于乌桕叶片SPAD。氮沉降、土壤微生物和不同乌桕种源可共同作用于光系统Ⅱ实际光合量子产率Y（Ⅱ），α和潜在最大相对电子传递速率（ETR_max）。因此，氮沉降与生物抑制剂对乌桕叶绿素荧光特性具有协同作用，入侵种源乌桕对土壤微生物控制的响应不明显，在微生物控制条件下依然具有较强的适应能力，因而具有较强的入侵能力。;Plant invasions cause damage to both function and stability of invaded ecosystems. Compared with plants from the native origin, the invasive origin plants are different in physiological characteristics, which make them stronger in competitive ability in resource utilization and environmental stress resistance. The chlorophyll fluorescence characteristics are closely related to photosynthetic efficiency and play important roles in plant growth and expansion. Additionally, increased nitrogen deposition is an important factor of global change, while soil microorganisms are crucial for plants to absorb and utilize soil nutrients. By application of soil microbial inhibitors to control the activities of bacterial communities (by streptomycin) or fungi communities (by iprodione), study on invasive plant Triadica sebifera was carried out using pot experiment to understand how different microbial communities affect the chlorophyll fluorescence characteristics of T. sebifera from both the native and invasive origins under the background of simulated nitrogen deposition. The study will be helpful in understanding the evolutionary characteristics and invasion mechanism of invasive plants, and provide a theoretical basis for effectively preventing and controlling invasive plants, reducing their damage to the invaded ecosystems. The study was performed using a nested design, Triadica sebifera was used as the research object with two origins, including native and invasive origins. Under the condition of nitrogen deposition, the difference in the chlorophyll fluorescence parameters of the two origins of T. sebifera were investigated by regulating soil bacteria and fungus. Results showed that, nitrogen deposition significantly increased the relative chlorophyll content (SPAD), the maximum quantum yield of photosystem II (F_v/F_m), non-photochemical quenching (NPQ), half-satiety and light intensity (I_K) of T. sebifera. The invasive origin of T. sebifera had lower SPAD than the native origin. The combination of nitrogen deposition and bacterial inhibitor significantly enhanced F_v/F_m, NPQ and I_K, and significantly reduced light energy utilization (α) and the SPAD. The bacterial inhibitors decreased the native T. sebifera α. Fungi inhibitors promoted I_K of the native T. sebifera and inhibited I_k of the invasive T. sebifera. Nitrogen deposition, biological inhibitor and T. sebifera origin can act together on the PSII actual photosynthetic quantum yield Y(Ⅱ), α and potential maximum relative electron transfer rate (ETR_max). Therefore, nitrogen deposition and fungi inhibitors had a synergistic effect on the chlorophyll fluorescence characteristics of T. sebifera. The invasive origin of T. sebifera had no obvious response to the control of soil microorganisms, so it still had a strong adaptability under the control of microorganisms, and thereby had strong invasion ability.

РОЗВИТОК АГРОПРОДОВОЛЬЧОЇ СФЕРИ ПІВДЕННОГО РЕГІОНУ

Global climate change factors and socio-economic consequences of the COVID-19 pandemic affect the current development of the agri-food sector of the Southern region of Ukraine. Agriculture is the main component of the agri-food sector. Economic development, food security of the region, living standards depend on agriculture. Crop and animal husbandry has a high level of development in the Southern region of Ukraine. The index of agricultural products has been fluctuating constantly in recent years. These oscillations have directions of decrease and directions of increase. However, the development of the agri-food sector has significantly decreased this year. The reason for the decrease is very negative climatic conditions, in particular, drought. Yields have fallen sharply, and companies are in a financial crisis. The state can help the affected enterprises and provide state support. Climatic and market conditions determine the need to adjust the development of the agri-food sector. New competitive varieties of grain are being introduced, which are able to ensure sustainable yields of high quality products in arid conditions of the steppe zone of southern Ukraine, work is being carried out on breeding highly productive breeds of sheep, sunflower hybrids are being created. It is important to introduce new cultures for the Southern region of Ukraine. Their cultivation should increase yields in arid climates. It is advisable to grow olives and make olive oil. The region has favorable conditions for growing peanuts, amaranth, saffron, sweet potatoes, chickpeas, asparagus, almonds. It is im-portant to improve the marketing component of traditional crops. The systematic implementation of the state policy of sustainable inno-vation and investment recovery and development with the involvement of public funds and resources of private business will contribute to ensuring the further development of the agri-food sector of the Southern region of Ukraine. The interaction between scientists, private enterprises, farmers, the state and other participants in ensuring the development of the agri-food sector on the basis of partnership is important. This interaction will help improve the implementation of the strategy for improving the agri-food sector. Similar trends will occur in the coming years. Comprehensive strategic reform of the agri-food sector of the southern region of Ukraine is necessary. This includes the improvement of traditional agricultural products. The introduction of innovations is crucial for further development. These measures will lead to the expansion of markets and economic growth.Keywords: agro-food sphere, agriculture, crop production, animal husbandry, viticulture, state support, innovations. Сучасний розвиток агропродовольчої сфери Південного регіону України обумовлений глобальними факторами зміни клімату та соціально-економічними наслідками пандемії COVID-19. Головною складовою агропродовольчої сфери є сільське господарство, яке має значний рівень розвитку в областях Південного регіону України. Протягом останніх років спостерігається щорічні коливання індексу сільськогосподарської продукції як у напрямках зменшення, так і збільшення показників. Однак, визначальні зміни у розвитку відбулись у поточному році, що обумовлене вкрай негативним впливом кліматичних умов на врожайність всіх основних сільськогосподарських культур та призвело до зменшення прибуткові кризового фінансового стану значної кількості господарств, які потребують державної підтримки для подальшого функціонування. Подібні тенденції будуть спостерігатись і в наступні роки, що вимагає комплексного стратегічного реформування агропродовольчої сфери Південного регіону України у напрямку удосконалення традиційної продукції, запровадження інновацій з метою розширення існуючих і формування нових ринків збуту. Ключові слова: агропродовольча сфера, сільське господарство, рослинництво, тваринництво, виноградарство, державна підтримка, інновації.

Identifying contributions of climatic and atmospheric changes to autumn phenology over mid-high latitudes of Northern Hemisphere

Variations in autumn phenology (i.e., the end of growing season, EOS) in recent decades have been suggested to be the dynamic response of terrestrial ecosystems to global environmental change. However, predicting EOS change with climate variation is still challenging, given that there are several environmental factors that can affect EOS apart from warming. In this study, EOS over the Northern Hemisphere (>30°) was calculated by three different extracting methods using the Normalized difference vegetation index (NDVI) records from the Global Inventory Modeling and Mapping Studies third generation (GIMMS3g) during 1982 to 2015. We used partial correlation and partial least-squares regression (PLSR) analyses to investigate the EOS variations in response to five global environmental change factors, including temperature, precipitation, insolation, atmospheric CO2 and nitrogen (N) deposition. We found that about 58.5% (13.6% were significant) of the study area showed earlier EOS trends and 41.5% (10.3% were significant) with later EOS. Warming played a critical role in regulating EOS. The cumulative precipitation during the preseason had the greatest positive impact on EOS in arid/semiarid regions. Sufficient insolation could contribute to the delayed EOS over high latitudes. Compared with climatic factors, EOS also showed high sensitivity to changes in the atmospheric factors, and the dominant control of atmospheric CO2 and N deposition on EOS was found at 25–30% of the areas. Our results confirmed the dominant role of climatic factors in regulating EOS, but other global environmental cues, for instance, elevated atmospheric CO2 concentration and increased atmospheric nitrogen (N) deposition should also be included in the autumn phenological model to further understand the carbon and N cycles of terrestrial ecosystems with climate change.

Vector–Borne infections in Pakistan do not come alone

Background: From 1995 till 2019, around 147,200 cases of dengue infection and more than 800 deaths are reported from Pakistan. Vector of dengue virus is mosquito Aedes which is capable of transmitting other viral infections like Chikungunya, Zika, and Yellow Fever. From 2016–2018, Chikungunya infection was reported in 776 patients. With exponential increase in population and utilization of resources, it is important to eradicate this mosquito. Methods and materials: The present study provides an in-depth analysis on the factors, both virological and environmental, responsible for making dengue infection and its vector Aedes endemic in Pakistan. For this study, phylogeographic analysis of dengue, and Chikungunya virus was conducted using BEAST program. Coalescent GMRF Bayesian Skyride and Brownian Random Walk model was selected as continuous traits substitution model. Data was collected to relate vector distribution, and conditions responsible in increasing Aedes population. Results: The Chikungunya virus in Pakistan originated from the nodes of Madhya Pradesh and Rajasthan, India in 2015. This virus spread in Malir, Karachi and in Bahawalpur, Punjab, Pakistan in 2016. CHIKV strains of Pakistan resemble Indian strains due to their origin. Dengue strains are closely related to Indian and Chinese isolates. Pakistan being the fifth most populous country with density population of 281, Comoros2, the main cities of Karachi and Hyderabad in Sind province; Lahore and Faisalabad in Punjab province; and Islamabad/Rawalpindi of federal area and Peshawar of KP make up 22 million of population. Climatic change is not the only factor responsible for increased vector population in areas. Other global change factors including, growing population, agriculture, deforestation, and urbanization equally and significantly contribute to spread of mosquitoes. All these factors add to breeding of Aedes mosquito in any region. Previously a dweller of greenery, this mosquito became domesticated through extensive travel and trade in different areas of Pakistan. Conclusion: First dengue became endemic in Pakistan, then Chikungunya was isolated form Pakistan. Each year resurfacing of dengue infection points towards future danger of spreading of other Aedes borne infections in Pakistan. It is not impossible to say that soon Zika infections will be reported from Pakistan.

Effects of climate change on parasites and disease in estuarine and nearshore environments.

Information on parasites and disease in marine ecosystems lags behind terrestrial systems, increasing the challenge of predicting responses of marine host–parasite systems to climate change. However, here I examine several generalizable aspects and research priorities. First, I advocate that quantification and comparison of host and parasite thermal performance curves is a smart approach to improve predictions of temperature effects on disease. Marine invertebrate species are ectothermic and should be highly conducive to this approach given their generally short generation times. Second, in marine systems, shallow subtidal and intertidal areas will experience the biggest temperature swings and thus likely see the most changes to host–parasite dynamics. Third, for some responses like parasite intensity, as long as the lethal limit of the parasite is not crossed, on average, there may be a biological basis to expect temperature-dependent intensification of impacts on hosts. Fourth, because secondary mortality effects and indirect effects of parasites can be very important, we need to study temperature effects on host–parasite dynamics in a community context to truly know their bottom line effects. This includes examining climate-influenced effects of parasites on ecosystem engineers given their pivotal role in communities. Finally, other global change factors, especially hypoxia, salinity, and ocean acidity, covary with temperature change and need to be considered and evaluated when possible for their contributing effects on host–parasite systems. Climate change–disease interactions in nearshore marine environments are complex; however, generalities are possible and continued research, especially in the areas outlined here, will improve our understanding.

The effects of elevated CO2, elevated O3, elevated temperature, and drought on plant leaf gas exchanges: a global meta-analysis of experimental studies.

Global change significantly influences plant leaf gas exchange, which affects the carbon-water cycle of terrestrial ecosystems. However, the magnitudes of the effects of multiple global change factors on leaf gas exchanges are currently lacking. Therefore, a global meta-analysis of 337 published articles was conducted to determine the effects of elevated CO2 (eCO2), elevated O3 (eO3), elevated temperature (eT), and drought on plant leaf gas exchanges. The results indicated that (1) the overall responses of photosynthesis rate (Pn) and instantaneous water use efficiency (WUEi) to eCO2 increased by 28.6% and 58.6%. But transpiration rate (Tr) and stomatal conductance (gs) responded negatively to eCO2 (- 17.5% and - 17.2%, respectively). Furthermore, all Pn, gs, and WUEi responded negatively to eO3 (- 32.7%, - 24.6%, and - 27.1%), eT (- 23.2%, - 10.8%, and - 28.9%), and drought (- 53.6%, - 59.3%, and - 4.6%, respectively), regardless of functional groups and various complex experimental conditions. (2) Elevated CO2 increased WUEi combined with eO3, eT, and drought (26.6%, 36.0%, and 58.6%, respectively, for eCO2 + eO3, eCO2 + eT, and eCO2 + drought) and mitigated their negative impacts on Pn to some extent. (3) Plant form and foliage type play an important role in the responses of leaf gas exchanges. Trees responded mostly to eCO2, but responded least to eT in Pn, Tr, gs, and WUEi compared with shrubs and herbs. Evergreen broad-leaved species were more responsive to eCO2 and drought. (4) The stress level of each factor can also significantly influence the responses of leaf gas exchanges to environment change. Hopefully, the quantitative results are helpful for the further assessments of the terrestrial carbon-water cycle.

Screening of spring wheat (Triticum aestivum L.) germplasm against drought and heat stress

Drought and heat stress are major indicators of global climate change and yield-limiting factors in wheat. Moreover, simultaneous occurrence of both factors could increase the injuries and greater yield losses in wheat species. In this scenario, there is need to screen germplasm and develop breeding lines which may show better resistance under the targeted condition. A germplasm comprising of 17 advanced lines, 4 elite checks and 79 accessions was compared to determine their resistance under controlled osmotic (− 0.9 MPa) and heat stress (40 °C) on the basis of various seedling traits. Heat and drought resistance index showed significant positive relationship with root mass showing the importance of this trait for selection under stress condition. Germplasm accession such as NARC-11022 possessed the highest drought and heat resistance index while standard check such as FSD-08 had the highest drought resistance index. These accessions may be exploited in breeding cultivars for multiple stress condition. Some advanced lines such as SU-100, SU-159 showed promising results under both types of stress, and these lines may be recommended for stress-prone environment.