Hasil untuk "Ecology"

Lu Yang, Huan He, Guangzhi Jiang et al.

Abstract Background Taraxasterol, a pentacyclic triterpenoid compound, has been widely used in traditional and modern medicine because of its pharmacological properties such as anti-inflammatory, antioxidative and antitumor effects. 2,3-oxidosqualene cyclase (OSC) is highly important for the generation of phytosterols and triterpenoid compounds and the structural diversity of natural products. However, the specific role of TmOSCs in the taraxasterol biosynthesis pathway has not yet been precisely resolved. Results In this study, 10 TmOSC gene family members were identified via the Taraxacum mongolicum (dandelion) genome and classified into three subgroups. Phylogenetic and collinearity analyses revealed evolutionary conservation among OSC proteins from Asteraceae species. RNA-seq data analysis revealed that TmOSC8 and TmOSC10 were highly expressed in nutrient-containing tissues. In addition, methyl jasmonate (MeJA) and abscisic acid (ABA) significantly induced the expression of TmOSC3, and the change in its relative expression was consistent with the taraxasterol content. The relative expression level of the TmOSC8-overexpressioning line was significantly increased by approximately 20 fold compared with that of the wild type, and the content of taraxasterol was significantly increased to 3 fold greater than that of the wild type. Conclusion This study systematically analyzed the evolutionary characteristics and expression patterns of the TmOSC gene family, suggested potential key roles of TmOSC3 and TmOSC8 in sterol synthesis and stress response, and provided a preliminary theoretical basis for the metabolic engineering of medicinal components in dandelion.

Jinrong Xu, Zhicheng Cheng, Li Dai et al.

Reproductive-stage drought arrests silk elongation, causing a greater anthesis-silking interval and subsequent kernel loss in maize. Exogenous brassinolide (BR) is known to increase drought tolerance; however, its influence on silk growth under water deficit remains unresolved. Here, we subjected maize to drought before tassel emergence (V13) and then applied foliar BR at concentrations of 0, 0.1, 0.5, or 1 mg mL⁻¹, with distilled water-sprayed plants serving as controls. Silk elongation under water-deficit stress was partially restored by 0.1 and 0.5 mg mL⁻¹ BR but suppressed by 1 mg mL⁻¹, with 0.5 mg mL⁻¹ increasing silk length by 2.9-fold compared to the stress control, recovering it to 26.5% of the well-watered level. This protection was underpinned by elevated antioxidant capacity (POD, SOD, and CAT by 31–77%, 12–46%, and 20–33%, respectively) and a 25–76% rise in proline relative to the distilled water-sprayed, which collectively curtailed oxidative damage, as evidenced by 36–67% reductions in O₂⁻ and H₂O₂ levels and a 24% decrease in MDA content. Critically, BR reprogrammed sugar metabolism: sucrose phosphate synthase (SPS) activity declined, while sucrose synthase (SS-I) and vacuolar invertase (VIN) activities surged, thereby shifting carbon partitioning from sucrose toward hexoses to sustain energy supply for silk growth. Genome-wide RNA-seq identified 6171 upregulated and 3295 downregulated genes, significantly enriched in 20 pathways, including starch/sucrose metabolism, glycolysis/gluconeogenesis, and phenylpropanoid biosynthesis. The expression of key genes, including sucrose invertase (INV) and hexokinase (HK), was significantly upregulated by 2.4- to 8.7-fold and 2.3- to 4.0-fold, respectively, compared to the distilled water-sprayed control. This multi-level analysis demonstrates that BR mitigates drought-induced silk growth arrest by orchestrating antioxidant defense, osmotic regulation, and metabolic reprogramming into a coordinated network, providing mechanistic insights into brassinosteroid-mediated reproductive stress adaptation in maize.

Juan J. Patiño-Cruz, Erick H. Ochoa-Chaparro, Eloy Navarro-León et al.

Efficient nitrogen assimilation in crops remains a key challenge for sustainable agriculture. This study investigated the physiological effects of foliar application of iodine on <i>Lactuca sativa</i> L. cv. Butterhead, comparing two different chemical forms—nanoparticulate iodine (INPs) and potassium iodide (KI)—selected to contrast a conventional ionic source with a nanoformulations of growing interest in plant nutrition. Plants were treated under passive hydroponic conditions with INPs and KI at concentrations of 40, 80, and 160 µM. The results showed that INPs at 40 µM significantly increased total biomass and soluble amino acid accumulation compared to the control, with no signs of phytotoxicity. In contrast, KI treatments significantly increased nitrate reductase activity, suggesting a role in the activation of the nitrogen pathway. However, neither form consistently outperformed the other across all evaluated variables. Yield and total chlorophyll content remained statistically unchanged between treatments, indicating a complex and form-dependent response. These findings highlight the differential physiological effects of iodine formulations on nitrogen-related metabolism and provide preliminary evidence for their potential integration into precision fertilization strategies focused on biochemical efficiency and metabolic modulation.

Tangzhe Nie, Jianfeng Li, Lili Jiang et al.

Enhancing irrigation and nitrogen fertilizer application has become a vital strategy for ensuring food security in the face of population growth and resource scarcity. A 2-year experiment was conducted to determine to investigate the effects of different irrigation lower limits and nitrogen fertilizer application amounts on millet growth, yield, water use efficiency (WUE), N utilization, and inorganic nitrogen accumulation in the soil in 2021 and 2022. The experiment was designed with four irrigation lower limits, corresponding to 50%, 60%, 70%, and 80% of the field capacity (FC), referred to as I₅₀, I₆₀, I₇₀, and I₈₀. Four nitrogen fertilizer application were also included: 0, 50, 100, and 150 kg·hm⁻² (designated as F₀₀, F₅₀, F₁₀₀, and F₁₅₀), resulting in a total of 16 treatments. Binary quadratic regression equations were established to optimize the irrigation and nitrogen application. The results demonstrated that the plant height, stem diameter, leaf area index, aboveground biomass, yield, spike diameter, spike length, spike weight, WUE, and nitrogen agronomic efficiency for millet initially increased before subsequently decreasing as the irrigation lower limit and nitrogen fertilizer application increased. Their maximum values were observed in the I₇₀F₁₀₀. However, the nitrogen partial factor productivity (PFPN) exhibited a gradual decline with increasing nitrogen application, reaching its peak at F₅₀. Additionally, PFPN displayed a pattern of initial increase followed by a decrease with rising irrigation lower limits. The accumulation of NO₃⁻-N and NH₄⁺-N in the 0~60 cm soil layer increased with the increase of nitrogen fertilizer application in both years, while they tended to decrease as the irrigation lower limit increased. An optimal irrigation lower limit of 64% FC to 74% FC and nitrogen fertilizer application of 80 to 100 kg ha⁻¹ was recommended for millet based on the regression equation. The findings of this study offer a theoretical foundation and technical guidance for developing a drip irrigation and fertilizer application for millet cultivation in Northeast China.

Louise G. Køhler, Bastian Huwer, José Martín Pujolar et al.

This data article includes a qualitative and quantitative description of the gelatinous macrozooplankton community of the North Sea during January-February 2021. Sampling was conducted during the 1st quarter International Bottom Trawl Survey (IBTS) on board the Danish R/V DANA (DTU Aqua Denmark) and the Swedish R/V Svea (SLU Sweden), as part of the ichthyoplankton investigation during night-time. A total of 147 stations were investigated in the western, central and eastern North Sea as well as the Skagerrak and Kattegat. Sampling was conducted with a 13 m long Midwater Ring Net (MIK net, Ø 2 m, mesh size 1.6 mm, cod end with smaller mesh size of 500 µm), equipped with a flow meter. The MIK net was deployed in double oblique hauls from the surface to c. 5 m above the sea floor [1,2]. Samples were visually analysed unpreserved on a light table and/or with a stereomicroscope or magnifying lamp within 2 hours after catch. A total of 13,510 individuals were counted/sized. Twelve gelatinous macrozooplankton species or genera were encountered, namely the hydrozoan Aequorea vitrina, Aglantha digitale, Clytia spp., Leuckartiara octona, Tima bairdii, Muggiaea atlantica; the scyphozoans Cyanea capillata and Cyanea lamarckii and the ctenophores Beroe spp., Bolinopsis infundibulum, Mnemiopsis leidyi, Pleurobrachia pileus. Abundance data are presented on a volume specific (m−3) and area specific (m−2) basis. Size data have been used to estimate wet weights based on published length-weight regressions (see Table 1). For the groups i) hydrozoan jellyfish, ii) scyphozoan jellyfish, iii) ctenophores, as well as iv) grouped gelatinous macrozooplankton, spatial weight specific distribution patterns are presented. This unpublished dataset contributes baseline information about the gelatinous macrozooplankton diversity and its specific distribution patterns in the extended North Sea area during winter (January-February) 2021. These data can be an important contribution to address global change impacts on marine systems, especially considering gelatinous macrozooplankton abundance changes in relation to anthropogenic stressors.

Stanislav Fedorenko, Lesya Vasylenko, Yuliia Bereznytska et al.

The development of environmental management in Ukraine is determined by the urgent need to overcome environmental problems and ensure the environmental safety of society, especially under the conditions of martial law. Today, the domestic economy is three times more resource-intensive than the world economy, the technological base and infrastructure complex of public production are rapidly wearing out, which leads to a decrease in the level of technological and environmental safety. Environmental management is related to the national economy and forms information about the need to use natural resources when promoting effective development. A comprehensive project-targeted approach to the development of new forms of ownership and market economy reflects the interrelationship of all parts of the nature management project. The development of the scientific foundations of nature management is facilitated by the formulation of a general plan for the placement of productive forces. The ecological situation in Ukraine has long been called a crisis. In recent decades, new scientific directions have appeared, the result of which have been new ideas about human, society and nature and their coexistence. One of these directions is environmental management, which today is the ideology of production activity management, as it provides an effective toolkit for solving current problems and preventing the emergence of new production environmental and economic issues.

Heather Alyson Shupe, Kai Jensen, Kristin Ludewig

Destructively sampling old Pedunculate oak (Quercus robur) trees on the active floodplain of the Middle Elbe to create an allometric equation to estimate carbon stocks (CS) and carbon sequestration rates (CSR) would defeat the purpose of protecting increasingly vulnerable and threatened primeval floodplain forests. To nondestructively estimate CS and CSR, we have adapted a two-parameter allometric equation which uses tree height (H) and diameter at breast height (DBH) (Dik 1984, Zianis et al. 2005) into a 1-parameter equation that requires only DBH to quantify stocks and annual changes in carbon stock (carbon sequestration rates) for individual Q. robur trees. The equations have also been adapted to estimate below- and above-ground carbon stocks of individual trees.The new method has: • Adapted a 2-parameter Quercus robur allometric equation which estimates tree volume to a 1-parameter equation which estimates above and below-ground carbon stock • Removed the requirement of tree height to reconstruct the carbon stock of trees at an annual timestep • An almost perfect linear relationship (Pearson R2= 0.998) between carbon sequestration rate and basal area increment (BAI)

Mariana Kluge, Christian Wurzbacher, Maxime Wauthy et al.

Measurement(s) carbon dioxide • methane • dissolved organic carbon • iron(2+) • iron(3+) • total phosphorous • Nitrate Measurement • sulfate • nitrite • ammonium • dissolved nitrogen atom in water • specific ultraviolet absorbance SUVA254 • spectral slope S289 • freshness index BIX • humification index HIX • fluorescence index FI • hydrogen to carbon ratio • oxygen to carbon ratio • m/z Technology Type(s) gas chromatography • total organic carbon analyzer • spectrophotometer • ion chromatography • total nitrogen analyzer • spectrofluorimeter • high-resolution mass spectrometry Factor Type(s) sampling site Sample Characteristic - Organism fungal sp. Sample Characteristic - Environment permafrost • pond water • sediment surface Sample Characteristic - Location Siberia • Sweden • Region of Northern Quebec • State of Alaska • Greenland Machine-accessible metadata file describing the reported data: https://doi.org/10.6084/m9.figshare.14896713

Silvia Jakabová, Martina Fikselová, Andrea Mendelová et al.

In this work, chemical parameters such as sugar (glucose and fructose) content, organic acid (total acids, malic and tartaric acids), total phenolic content and the antioxidant activity of 12 white wines (chardonnay, pinot blanc and pinot gris) from various wine regions in Slovakia were studied in order to identify differences among the varieties and wine-growing regions. The wine samples were examined by Fourier-transform infrared spectroscopy (FTIR) and UV-VIS spectrophotometry (for determination of total polyphenolic content (TPC) and total antioxidant activity (TAA)) methods. Content of alcohol ranged between 11.50% and 13.80% with the mean value 12.52%. Mean content of total acids varied between 4.63 ± 0.09 and 6.63 ± 0.05 g.L⁻¹, tartaric acid varied between 1.62 ± 0.09 and 2.93 ± 0.03 g L⁻¹, malic acid was found in the concentrations ranged from 0.07 ± 0.05 and 2.50 ± 0.08 g L⁻¹ and lactic acid was present between 1.53 and 0.01 g L⁻¹. The content of fructose was, in general, higher in the samples from the Južnoslovenská and Nitrianska wine regions and glucose was higher in the Malokarpatská wine region. Chardonnay wines showed the highest content of total polyphenols and the antioxidant activity in the samples ranged from 51.06 ± 027 to 72.53 ± 0.35% inhibition of DPPH. The PCA analysis based on chemical descriptors distinguished the Nitrianska and Stredoslovenská wine regions. According to similarities among the wine samples, four main classes were formed by cluster analysis.

Ami Bennett, David H. Duncan, Libby Rumpff et al.

Abstract Ecological restoration of degraded ecosystems requires the facilitation of natural regeneration by plants, often augmented by large‐scale active revegetation. The success of such projects is highly variable. Risk factors may be readily identifiable in a general sense, but it is rarely clear how they play out individually, or in combination. We addressed this problem with a field experiment on the survival of, and browsing damage to, 1275 hand‐planted buloke (Allocasuarina luehmannii) seedlings in a nationally endangered, semi‐arid woodland community. Buloke seedlings were planted in 17 sites representing four landscape contexts and with three levels of protection from kangaroo and lagomorph browsing. We censused seedlings and measured herbivore activity four times during the first 400 d post‐planting and fitted models of mortality and browse hazard to these data using survival analysis. Increasing lagomorph activity was associated with higher mortality risk, while kangaroo activity was not. Seedling survival was lowest for each treatment within extant buloke woodland, and the highest survival rates for guarded seedlings were in locations favored by lagomorphs. Damage from browsing was nearly ubiquitous after one year for surviving unguarded seedlings, despite moderate browser activity. On average, unguarded seedlings showed a decline in height, whereas fully guarded seedlings grew 2.3 cm across the survey period. This study demonstrates buloke seedlings should be protected from browsers, even with browsers maintained at moderate to low density, and the location that maximizes survival, and possibly growth rates, is adjacent to dunes. Further work will test this heuristic in an analysis of cost‐effective revegetation strategies for this endangered community.

Vincent Raoult, Clive N. Trueman, Kelsey M. Kingsbury et al.

Determining the geographic range of widely dispersed or migratory marine organisms is notoriously difficult, often requiring considerable costs and typically extensive tagging or exploration programs. While these approaches are accurate and can reveal important information on the species, they are usually conducted on only a small number of individuals and can take years to produce relevant results, so alternative approaches may be preferable. The presence of latitudinal gradients in stable carbon isotope compositions of marine phytoplankton offers a means to quickly determine likely geographic population ranges of species that rely on productivity from these resources. Across sufficiently large spatial and temporal scales, the stable carbon isotopes of large coastal or pelagic marine species should reflect broad geographic patterns of resource use, and could be used to infer geographic ranges of marine populations. Using two methods, one based on a global mechanistic model and the other on targeted low-cost latitudinal sampling of fishes, we demonstrate and compare these stable isotope approaches to determine the core population geography of an apex predator, the great hammerhead (Sphyrna mokarran). Both methods indicated similar geographic ranges and suggested that S. mokarran recorded in south-eastern Australia are likely to be from more northern Australian waters. These approaches could be replicated in other areas where coastlines span predictable geographic gradients in isotope values and be used to determine the core population geography of highly mobile species to inform management decisions.

K. Mellanby

B. Hazlett

Oswaldo Coca-Domínguez, Constanza Ricaurte-Villota

A hazard and vulnerability assessment of coastal erosion is an essential first step for planning and decision-making, because it is part of risk management and its results are in the form of easily interpreted traffic-light maps. For the analysis of the assessment in this work, a methodology is proposed which considers three components for both hazard (magnitude, occurrence, and susceptibility) and vulnerability (exposure, fragility, and lack of resilience), through a semi-quantitative approximation, by applying relative indices to different variables. This methodology has been adapted to analyze hazards and vulnerability caused by coastal erosion combining physical and social aspects. For the validation of this methodology, Spratt Bight Beach (Colombian Caribbean) and La Bocana beach (Colombian Pacific) were selected in order to have contrasting regions and to validate the application of the method over a geographical range. One of the most significant outcomes of the assessment of the degree of hazard and vulnerability is that the rating may represent different combinations of factors. It is therefore important to study and interpret the components separately, allowing us to propose corrective and/or prospective focused interventions at local and regional levels. In terms of vulnerability, the assessment highlighted the importance of cultural ecology as a factor of resilience to coastal hazards.

Ella Ayu Oktami, Tutut Sunarminto, Harnios Arief

<p><em>The existence of the Djuanda Forest Park near the urban area indirectly indicates that the area is close to the city community. The attitude of city people who tend to have an attitude of being able to take care of themselves without having to depend on others is feared to enter the surrounding communities and subsequently influence the development of </em><em>Djuanda </em><em>Tahura ecotourism. The research objective was to measure public perceptions of ecotourism and ecotourism objects in the Djuanda Forest Park, measuring community participation in the development of ecotourism in Djuanda Forest Park, and developing a strategy for increasing community participation in developing ecotourism in Djuanda Forest Park. The method used is observation, questionnaire, interview, and literature study. Communities strongly agree that ecotourism must meet indicators of community involvement, ecology, conservation, culture, education, and visitor satisfaction. The community considers that the Djuanda Tahura has beautiful ecotourism objects (highest average score = 4.61). The community values both ecotourism and the object of ecotourism because the community has a sense of care and sense of belonging to the Djuanda Tahura as an area that can provide benefits, both in ecological, social and economic aspects. However, community participation in ecotourism development is only in the implementation and acceptance of benefits and has participation in the form of personnel and expertise. Based on people's perceptions and participation, the community is at the lowest level of participation, so an SO strategy is needed, namely by utilizing all the strengths to make the most of opportunities</em><em>.</em></p><p><em> </em></p><p><em>Keywords: Forest Park Ir H Djuanda</em><em>,</em><em> participation, perception,</em><em> </em><em>society, strategy </em></p>

A. Underwood

J. Denslow

J. L. Gittleman, P. Harvey

J. Green

J. Wiens, Bruce T. Milne