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1.
Braz. j. biol ; 84: e252143, 2024. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1364526

RESUMO

Cadmium (Cd) is one of non-essential heavy metals which is released into environment naturally or anthropogenically. It is highly persistent toxic metals that are exceptionally distressing industrial and agriculture activities by contaminating soil, water and food. Its long-duration endurance in soil and water results in accumulation and uptake into plants, leading to the food chain. This becomes a serious global problem threatening humans and animals as food chain components. Living organisms, especially humans, are exposed to Cd through plants as one of the main vegetative food sources. This review paper is concentrated on the symptoms of the plants affected by Cd toxicity. The absorption of Cd triggers several seen and unseen symptoms by polluted plants such as stunted growth, chlorosis, necrosis and wilting. Apart from that, factors that affect the uptake and translocation of Cd in plants are elaborated to understand the mechanism that contributes to its accumulation. By insight of Cd accumulation, this review also discussed the phytoremediation techniques-phytoextraction, phytostimulation, phytostabilization, phytovolatization and rhizofiltration in bioremediating the Cd.


O cádmio (Cd) é um dos metais pesados ​​não essenciais que é liberado no meio ambiente de forma natural ou antropogênica. São metais tóxicos altamente persistentes que prejudicam excepcionalmente as atividades industriais e agrícolas, contaminando o solo, a água e os alimentos. Sua resistência de longa duração no solo e na água resulta em acúmulo e absorção pelas plantas, levando à cadeia alimentar. Isso se torna um sério problema global que ameaça humanos e animais como componentes da cadeia alimentar. Os organismos vivos, principalmente os humanos, são expostos ao Cd através das plantas como uma das principais fontes de alimento vegetativo. Este artigo de revisão concentra-se nos sintomas das plantas afetadas pela toxicidade do Cd. A absorção de Cd desencadeia vários sintomas visíveis e invisíveis por plantas poluídas, como crescimento atrofiado, clorose, necrose e murcha. Além disso, são elaborados fatores que afetam a absorção e translocação de Cd nas plantas para entender o mecanismo que contribui para o seu acúmulo. A partir do conhecimento do acúmulo de Cd, esta revisão também discutiu as técnicas de fitorremediação - fitoextração, fitoestimulação, fitoestabilização, fitovolatização e rizofiltração na biorremediação do Cd.


Assuntos
Plantas/toxicidade , Cádmio , Metais Pesados , Alimentos/toxicidade
2.
Braz. j. biol ; 84: e257969, 2024. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1364513

RESUMO

In this study, we evaluated variation in vegetative and reproductive phenological events of four phylogenetically related plant species subjected to a seasonal environment. To this aim, we sampled 15 individuals of each plant species every fortnight for one year, between January and December of 2017. To assess when a given phenophase occurred more intensely in the population, the Fournier intensity index was used and the synchrony of individuals of the sample in a given phenological event was estimated using the activity index. The Rayleigh (Z) test was used to determine whether the phenological events have seasonal distribution. The relationship of abiotic factors (photoperiod, precipitation, relative humidity and temperature) with the intensity of phenophases was evaluated for each plant species using generalized linear models (GLMs). The phenophases of all plants showed a seasonal distribution pattern, as well as variation in synchrony of phenophases and specific sets of abiotic factors significantly influenced their phenophases. New leaves, for example, were produced throughout the seasons, with intense leaf fall in the dry season. Flowering periods, on the other hand, did not overlap. Indeed, species exhibited sequential flowering and asynchronous flowering among individuals. Our results suggest that the phenological patterns of four sympatric plant species are directly linked to climatic variables, but different abiotic factors affected different phenophases.


Neste estudo, avaliamos a variação nos eventos fenológicos vegetativos e reprodutivos de quatro espécies de plantas filogeneticamente relacionadas submetidas a um ambiente sazonal. Para isso, amostramos 15 indivíduos de cada espécie quinzenalmente, pelo período de um ano, entre janeiro e dezembro de 2017. Para avaliar quando uma determinada fenofase ocorreu de modo mais intenso na população foi utilizado o índice de intensidade de Fournier e a sincronia dos indivíduos da amostra em determinado evento fenológico foi estimada utilizando-se o índice de atividade. O teste de Rayleigh (Z) foi usado para determinar se os eventos fenológicos têm distribuição sazonal. A relação dos fatores abióticos (fotoperíodo, precipitação, temperatura e umidade relativa) com a intensidade das fenofases foi avaliada para cada espécie de planta usando modelos lineares generalizados (GLMs). As fenofases de todas as plantas apresentaram um padrão de distribuição sazonal, bem como variação na sincronia das fenofases e conjuntos específicos de fatores abióticos influenciaram significativamente suas fenofases. Folhas novas, por exemplo, foram produzidas ao longo das estações, com intensa queda de folhas na estação seca. Os períodos de floração, por outro lado, não se sobrepuseram. De fato, as espécies exibiram floração sequencial e floração assíncrona entre os indivíduos. Nossos resultados sugerem que os padrões fenológicos das quatro espécies de plantas simpátricas estão diretamente ligados às variáveis climáticas, mas diferentes fatores abióticos afetaram diferentes fenofases.


Assuntos
Plantas , Estações do Ano , Crescimento e Desenvolvimento , Meio Ambiente , Simpatria/fisiologia
4.
Braz. j. biol ; 84: e255485, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1350312

RESUMO

Abstract The current focus is on the overall pattern of seed storage present in the fragments of the soil of piedmont and alluvial landscapes of the environment. The present study predicted the seed banks of both soils of alluvial and piedmont zones in different ecological conditions and evaluate the potential of seeds in the restoration of both environments. The composition of the seed bank of soil is mainly affected by the alluvial environment and the structure of cleared area shows that more species of germinating annual grasses and growable seeds with the higher total number. Extant vegetation structures have an important role in the diversity of soil seed reservoirs, whose composition corresponded with the openness of the site. When in situ soil seed bank is recruited, it helps to restore only some components of the plant community in an alluvial environment. In our current research, it was confirmed that seed richness was higher in number at lower elevation (alluvial) than that at high elevation (piedmont). Seed richness showed a significant negative correlation with anions, cations, while significantly positive with altitude that suggests the richness pattern of the overall seed bank of the area is influenced by various environmental factors.


Resumo O foco atual está no padrão geral de armazenamento de sementes presente nos fragmentos de solo do Piemonte e nas paisagens aluviais do meio ambiente. O presente estudo previu os bancos de sementes de ambos os solos das zonas aluvial e piemontesa em diferentes condições ecológicas e avaliou o potencial das sementes na restauração de ambos os ambientes. A composição do banco de sementes do solo é afetada principalmente pelo ambiente aluvial e a estrutura da área desmatada mostra que mais espécies de gramíneas anuais em germinação e sementes cultiváveis ​​apresentam o maior número total. As estruturas da vegetação existente têm um papel importante na diversidade dos reservatórios de sementes do solo, cuja composição correspondeu à abertura do local. Quando o banco de sementes do solo in situ é recrutado, o mesmo ajuda a restaurar apenas alguns componentes da comunidade de plantas em um ambiente aluvial. Em nossa pesquisa atual, foi confirmado que a riqueza de sementes era maior em número em altitudes mais baixas (aluviais) do que em altitudes elevadas (Piemonte). A riqueza de sementes mostrou uma correlação negativa significativa com ânions, cátions, enquanto significativamente positiva com a altitude, o que sugere que o padrão de riqueza do banco geral de sementes da área é influenciado por vários fatores ambientais.


Assuntos
Solo , Banco de Sementes , Paquistão , Plantas , Sementes , Ecossistema , Poaceae
5.
J Ethnobiol Ethnomed ; 19(1): 1, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36597154

RESUMO

BACKGROUND: Baka hunter-gatherers have a well-developed traditional knowledge of using plants for a variety of purposes including hunting and fishing. However, comprehensive documentation on the use of plants for hunting and fishing in eastern Cameroon is still lacking. METHOD: This study aimed at recording plants used for hunting and fishing practices, using focus group discussion, interviews and field surveys with 165 Baka members (90 men and 75 women) of different age groups in 6 villages. RESULTS: The most frequent techniques used for hunting and fishing are the use of animal traps, fishing lines, dam fishing, hunting with dogs and spear hunting. We recorded a total of 176 plant species used in various hunting practices, the most frequently cited one being Zanthoxylum gilletii (De Wild.) P.G.Waterman, Greenwayodendron suaveolens (Engl. & Diels) Verdc., Microcos coriacea (Mast.) Burret, Calamus deërratus G.Mann & H.Wendl. and Drypetes sp. These plants are used for a variety of purposes, most frequently as hunting luck, psychoactive for improving the dog's scent and capacity for hunting, materials for traps, and remedies for attracting animals and for making the hunter courageous. CONCLUSION: Plants used for hunting purposes here are embedded in a complex ecological and cultural context based on morphological characteristics, plant properties and local beliefs. This study provides a preliminary report and leaves room for further investigations to improve the documentation of the traditional knowledge systems of the studied community.


Assuntos
Caça , Conhecimento , Feminino , Camarões , Grupos Focais , Inquéritos e Questionários , Humanos , Masculino , Plantas
6.
Nutrients ; 15(2)2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36678322

RESUMO

Neurodegenerative diseases are known for their wide range of harmful conditions related to progressive cell damage, nervous system connections and neuronal death. These pathologies promote the loss of essential motor and cognitive functions, such as mobility, learning and sensation. Neurodegeneration affects millions of people worldwide, and no integral cure has been created yet. Here, bioactive compounds have been proven to exert numerous beneficial effects due to their remarkable bioactivity, so they could be considered as great options for the development of new neuroprotective strategies. Phenolic bioactives have been reported to be found in edible part of plants; however, over the last years, a large amount of research has focused on the phenolic richness that plant by-products possess, which sometimes even exceeds the content in the pulp. Thus, their possible application as an emergent neuroprotective technique could also be considered as an optimal strategy to revalorize these agricultural residues (those originated from plant processing). This review aims to summarize main triggers of neurodegeneration, revise the state of the art in plant extracts and their role in avoiding neurodegeneration and discuss how their main phenolic compounds could exert their neuroprotective effects. For this purpose, a diverse search of studies has been conducted, gathering a large number of papers where by-products were used as strong sources of phenolic compounds for their neuroprotective properties. Finally, although a lack of investigation is quite remarkable and greatly limits the use of these compounds, phenolics remain attractive for research into new multifactorial anti-neurodegenerative nutraceuticals.


Assuntos
Doenças Neurodegenerativas , Fármacos Neuroprotetores , Humanos , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/química , Fenóis/farmacologia , Fenóis/química , Antioxidantes/farmacologia , Antioxidantes/química , Doenças Neurodegenerativas/prevenção & controle , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Plantas/química
7.
J Agric Food Chem ; 71(3): 1291-1309, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36625507

RESUMO

Plant virus disease is the second most prevalent plant diseases and can cause extensive loss in global agricultural economy. Extensive work has been carried out on the development of novel antiplant virus agents for preventing and treating plant virus diseases. In this review, we summarize the achievements of the research and development of new antiviral agents in the recent five years and provide our own perspective on the future development in this highly active research field.


Assuntos
Antivirais , Vírus de Plantas , Plantas
8.
Proc Biol Sci ; 290(1990): 20222203, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36629117

RESUMO

Abandonment of agricultural lands promotes the global expansion of secondary forests, which are critical for preserving biodiversity and ecosystem functions and services. Such roles largely depend, however, on two essential successional attributes, trajectory and recovery rate, which are expected to depend on landscape-scale forest cover in nonlinear ways. Using a multi-scale approach and a large vegetation dataset (843 plots, 3511 tree species) from 22 secondary forest chronosequences distributed across the Neotropics, we show that successional trajectories of woody plant species richness, stem density and basal area are less predictable in landscapes (4 km radius) with intermediate (40-60%) forest cover than in landscapes with high (greater than 60%) forest cover. This supports theory suggesting that high spatial and environmental heterogeneity in intermediately deforested landscapes can increase the variation of key ecological factors for forest recovery (e.g. seed dispersal and seedling recruitment), increasing the uncertainty of successional trajectories. Regarding the recovery rate, only species richness is positively related to forest cover in relatively small (1 km radius) landscapes. These findings highlight the importance of using a spatially explicit landscape approach in restoration initiatives and suggest that these initiatives can be more effective in more forested landscapes, especially if implemented across spatial extents of 1-4 km radius.


Assuntos
Ecossistema , Florestas , Biodiversidade , Árvores , Plantas
9.
Artigo em Inglês | MEDLINE | ID: mdl-36673887

RESUMO

Restoring endangered plant species to their historical sites is not always possible due to constantly changing habitat conditions. The aim of this study was to test the effects of reintroduction of two relict willow species in eastern Poland. The experiment consisted of planting 48 individuals of Salix lapponum and S. myrtilloides, obtained by micropropagation, at each of the two selected sites and observing their survival after one year. At the same time, selected physicochemical and biocenotic factors of the environment were monitored. About 70% of S. lapponum individuals and 50% of S. myrtilloides plants survived the one-year period. This result can be considered satisfactory and confirms the effectiveness of this means of active protection. The results of measurements of selected abiotic factors of the environment and the observations and ecological analysis of the flora indicated that the habitat conditions of both historical sites have changed, resulting in accelerated succession of vegetation. However, complete habitat degradation did not occur, although the development of a multi-story structure of one of the phytocenoses intensified competition for light and other environmental resources, which narrowed the potential ecological niche of the reintroduced species.


Assuntos
Espécies em Perigo de Extinção , Salix , Humanos , Animais , Ecossistema , Plantas , Biota
11.
Brief Bioinform ; 24(1)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36644898

RESUMO

Unlike the typical single circular structure of most animal mitochondrial genomes (mitogenome), the drastic structural variation of plant mitogenomes is a result of a mixture of molecules of various sizes and structures. Obtaining the full panoramic plant mitogenome is still considered a roadblock in evolutionary biology. In this study, we developed a graph-based sequence assembly toolkit (GSAT) to construct the pan-structural landscape of plant mitogenome with high-quality mitochondrial master graphs (MMGs) for model species including rice (Oryza sativa) and thale cress (Arabidopsis thaliana). The rice and thale cress MMGs have total lengths of 346 562 and 358 041 bp, including 9 and 6 contigs and 12 and 8 links, respectively, and could be further divided into 6 and 3 minimum master circles and 4 and 2 minimum secondary circles separately. The nuclear mitochondrial DNA segments (NUMTs) in thale cress strongly affected the frequency evaluation of the homologous structures in the mitogenome, while the effects of NUMTs in rice were relatively weak. The mitochondrial plastid DNA segments (MTPTs) in both species had no effects on the assessment of the MMGs. All potential recombinant structures were evaluated, and the findings revealed that all, except for nuclear-homologous structures, MMG structures are present at a much higher frequency than non-MMG structures are. Investigations of potential circular and linear molecules further supported multiple dominant structures in the mitogenomes and could be completely summarized in the MMG. Our study provided an efficient and accurate model for assembling and applying graph-based plant mitogenomes to assess their pan-structural variations.


Assuntos
Genoma Mitocondrial , Animais , DNA Mitocondrial/genética , Evolução Biológica , Mitocôndrias/genética , Plantas/genética , Filogenia
12.
Plant Signal Behav ; 18(1): 2163343, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36655720

RESUMO

Abiotic stress is considered as the main culprit for reduction of global food production. Recent studies have reported GABA as a major regulator of abiotic stress and thus opening new avenues in research on emerging roles of GABA in abiotic stress acclimation in plants.


Assuntos
Estresse Fisiológico , Ácido gama-Aminobutírico , Plantas/genética
13.
Environ Monit Assess ; 195(2): 263, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36600112

RESUMO

Agroforestry parklands are an age-old traditional land use practice that integrates crop cultivation under scattered woody plants. This practice is widespread in West African savannas providing many essential ecological and socio-economic benefits to people such as food, fuelwood, and medicine. Currently, parklands are decreasing due to changes in agriculture and land use practices, often associated with human population growth. Understanding spatial patterns as well as identifying reliable methods of sampling to estimate the density of woody plants is necessary for the sustainable management of parklands. In this study, a comparative analysis of select plotless sampling methods was performed using field and simulated datasets with known spatial patterns from field assessments. Results of spatial indices tests indicated that woody plants in parklands exhibited two spatial patterns: i.e., aggregate and random, the latter being the dominant pattern observed in field datasets. Based on relative measure statistics (i.e., RRMSE and RBIAS), the ordered distance (OD), point-centered quarter (PCQ), and closest individual (CI) methods performed well when woody plants were located in a random pattern while the variable area transect (VAT) method was better at estimating density under patterns of spatial aggregation. Overall, OD and VAT methods are recommended for density estimation in parklands because they are relatively more accurate, less biased, and practical and computations are easy to undertake.


Assuntos
Monitoramento Ambiental , Pradaria , Humanos , Agricultura , Plantas , Madeira
14.
Sci Rep ; 13(1): 208, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36604463

RESUMO

Tundra plants are widely considered to be constrained by cool growing conditions and short growing seasons. Furthermore, phenological development is generally predicted by daily heat sums calculated as growing degree days. Analyzing over a decade of seasonal flower counts of 23 plant species distributed across four plant communities, together with hourly canopy-temperature records, we show that the timing of flowering of many tundra plants are best predicted by a modified growing degree day model with a maximum temperature threshold. Threshold maximums are commonly employed in agriculture, but until recently have not been considered for natural ecosystems and to our knowledge have not been used for tundra plants. Estimated maximum temperature thresholds were found to be within the range of daily temperatures commonly experienced for many species, particularly for plants at the colder, high Arctic study site. These findings provide an explanation for why passive experimental warming-where moderate changes in mean daily temperatures are accompanied by larger changes in daily maximum temperatures-generally shifts plant phenology less than ambient warming. Our results also suggest that many plants adapted to extreme cold environments may have limits to their thermal responsiveness.


Assuntos
Ecossistema , Temperatura Alta , Temperatura , Mudança Climática , Regiões Árticas , Estações do Ano , Tundra , Plantas
15.
Sci Rep ; 13(1): 182, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36604574

RESUMO

Due to their sessile nature, plants are exposed to various environmental stressors such as exposure to high levels of harmful ultraviolet (UV), ionizing, and non-ionizing radiations. This exposure may result in various damages, ranging from DNA and chromosomal aberrations to phenotypic abnormalities. As an adaptation, plants have evolved efficient DNA repair mechanisms to detect and repair any damage caused by exposure to these harmful stressors to ensure their survival. In this study, the effects of gamma radiation (as a source of ionizing radiation) on clonal Ananas comosus var. MD2 was evaluated. The morphology and physiology of the clonal plantlets before and after exposure to gamma radiation were monitored at specific time intervals. The degree of genetic variation between the samples pre- and post-irradiation was also analyzed by using inter-simple sequence repeat (ISSR) markers. The resulting data revealed that the heights of the irradiated plantlets were significantly reduced (compared to control), but improved with the recovery period. Irradiated samples also exhibited relatively good photosynthetic efficiency that further improved as the plantlets recover. These observations were supported by the ISSR analysis, where the genetic dissimilarities between the irradiated samples and control were reduced by 0.1017, after 4 weeks of recovery. Overall, our findings suggested that the phenotype recovery of the clonal A. comosus var. MD2 plantlets was contributed by their ability to detect and repair the DNA lesions (as exemplified by the reduction in genetic dissimilarity after 4 weeks) and hence allow the plantlets to undergo phenotype reversion to normal plant stature.


Assuntos
Ananas , Ananas/genética , Radiação Ionizante , Raios gama/efeitos adversos , Reparo do DNA/genética , Fenótipo , Plantas
16.
New Phytol ; 237(4): 1074-1077, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36655592
17.
Plant Signal Behav ; 18(1): 2163869, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36635991

RESUMO

Control of hazardous indoor particles using plants has attracted interest due to the increasing worldwide air pollution and spread of pandemic-causing viruses. However, the interaction between human pathogenic viruses (HPVs) and live plants has not been examined largely due to issues in detecting tiny amounts of infectious viruses in a carrier (such as an aerosol) and the lack of suitable examination methods. In this study, as a novel evaluation method, the effect of submerged leaves of live plants on HPVs in water was examined, using the H1N1 influenza virus as a model. Selected plant foliage of a live plant was immersed in a small bag containing HPV water suspension. In an initial screening test, the activities of 20 different plant species on the virus suspension were evaluated using a rapid virus detection kit. Ten plant species had the capability to decrease virus concentrations in the water suspension within 72 h. Among the experimental plant species, Epipremnum aureum showed the highest virus decreasing characteristics when examined using both the kit and quantitative real time polymerase chain reaction. The capacity of immersed leaf of live E. aureum to decrease viral content was enhanced when the plant-containing pot was electrically grounded to the earth (approximately 70% decrease in virus concentration). The foliage sample analysis showed that virus adsorption to the plant foliage surface could be the major reason for the decrease in the suspension. These results suggest that the proposed method can be applied to select plants to further investigate plant-HPV interactions.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Infecções por Papillomavirus , Humanos , Plantas , Folhas de Planta , Água
18.
Plant Signal Behav ; 18(1): 2163349, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36645912

RESUMO

Planting Elymus nutans artificial grassland to replace degraded Artemisia baimaensis grassland on the Qinghai Tibetan plateau (QTP) can effectively alleviate local grass-livestock imbalance. However, it is unknown whether the allelopathy of natural grassland plant A. baimaensis on E. nutans affects grassland establishment. Accordingly, we examined the effects of varying concentrations of aqueous extracts of A. baimaensis litter on the seed germination and early seedling growth of E. nutans, and the effects of A. baimaensis volatile organic compounds (VOCs) on the growth parameters and physiological characteristics of E. nutans. The results indicate that the aqueous extract inhibited the force, percentage, and index of germination of E. nutans and affected early seedling growth, particularly at high concentrations. Further, the VOCs significantly reduced the aboveground and root biomass of E. nutans and increased malondialdehyde concentrations. Additionally, these VOCs altered the antioxidant enzyme activities and increased the superoxide dismutase, peroxidase, ascorbic acid peroxidase, soluble sugar, and proline content but significantly decreased glutathione reductase levels. Our results indicate that the allelopathy of A. baimaensis significantly inhibited the germination and seedling growth of E. nutans . Thus, the leaching of A. baimaensis may produce allelochemicals in the soil that inhibit the germination of E. nutans seeds. Moreover, the VOCs of A. baimaensis may disrupt the growth process, resulting in a decrease in biomass and a disruption of the physiological metabolism of seedlings under field conditions.


Assuntos
Artemisia , Elymus , Elymus/metabolismo , Pradaria , Alelopatia , Plântula , Germinação , Plantas , Sementes , Peroxidases/metabolismo , Peroxidases/farmacologia
19.
Sci Rep ; 13(1): 902, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650198

RESUMO

The extinction of a species in a plant-pollinator mutualistic community can cause cascading effects and lead to major biodiversity loss. The ecologically important task of predicting the severity of the cascading effects is made challenging by the complex network of interactions among the species. In this work, we analyze an ensemble of models of communities of plant and pollinator species. These models describe the mutualistic inter-species interactions by Boolean threshold functions. We show that identifying generalized positive feedback loops can help pinpoint the species whose extinction leads to catastrophic and substantial damage to the whole community. We compare these results with the damage percentage caused by the loss of species identified as important by previously studied structural measures and show that positive feedback loops and the information gained from them can identify certain crucial species that the other measures fail to find. We also suggest mitigation measures for two specific purposes: (1) prevent the damage to the community by protecting a subset of the species, and (2) restore the community after the damage by restoring a subset of species. Our analyses indicate that the generalized positive feedback loops predict the most efficient strategies to achieve these purposes. The correct identification of species in each category has important implications for conservation efforts and developing community management strategies.


Assuntos
Biodiversidade , Polinização , Retroalimentação , Plantas , Ecossistema
20.
Sci Rep ; 13(1): 877, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650209

RESUMO

Nitrogen (N) deposition might alleviate degradation of alpine grassland caused by N limitation on the Tibetan Plateau (TP). To determine such limitation and quantify the N-induced N retention in plant, a six-year fertilization experiment with six levels of N addition rates (0, 1, 2, 4, 8 and 16 g N m-2 yr-1) was conducted in the Namco alpine steppe and additional 89 experiments with multi-level N addition were also synthesized worldwide among which 27 sites were on the TP. In general, N addition promoted N retention in plants, and this increasing trend diminished at the critical N rate (Ncr). The maximum N retention capacity (MNRC) of plants at Ncr was strongly correlated with initial aboveground net primary productivity with a slope of 0.02, and the MNRC of grasslands globally ranged from 0.35 to 42.59 g N m-2 yr-1, approximately account for 39% of Ncr. Tibetan alpine grassland had a low average MNRC (2.24 g N m-2 yr-1) with distinct regional characteristic, which was much lower in the western TP (0.80 g N m-2 yr-1) than the eastern TP (4.10 g N m-2 yr-1). Our results inferred 0.33-1.21 Tg N yr-1 (0.22-0.79 g N m-2 yr-1) can be retained and 5.65-20.11 Tg C yr-1 (3.67-13.06 g C m-2 yr-1) can be gained by Tibetan alpine grasslands under current N deposition level. With the aggravation of N deposition, the alpine steppe ecosystem might continuously absorb N and C until N deposition reaches Ncr.


Assuntos
Ecossistema , Pradaria , Tibet , Biomassa , Nitrogênio/metabolismo , Solo , Plantas/metabolismo
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