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1.
Philos Trans R Soc Lond B Biol Sci ; 379(1902): 20230335, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38583469

RESUMO

European grasslands are among the most species-rich ecosystems on small spatial scales. However, human-induced activities like land use and climate change pose significant threats to this diversity. To explore how climate and land cover change will affect biodiversity and community composition in grassland ecosystems, we conducted joint species distribution models (SDMs) on the extensive vegetation-plot database sPlotOpen to project distributions of 1178 grassland species across Europe under current conditions and three future scenarios. We further compared model accuracy and computational efficiency between joint SDMs (JSDMs) and stacked SDMs, especially for rare species. Our results show that: (i) grassland communities in the mountain ranges are expected to suffer high rates of species loss, while those in western, northern and eastern Europe will experience substantial turnover; (ii) scaling anomalies were observed in the predicted species richness, reflecting regional differences in the dominant drivers of assembly processes; (iii) JSDMs did not outperform stacked SDMs in predictive power but demonstrated superior efficiency in model fitting and predicting; and (iv) incorporating co-occurrence datasets improved the model performance in predicting the distribution of rare species. This article is part of the theme issue 'Ecological novelty and planetary stewardship: biodiversity dynamics in a transforming biosphere'.


Assuntos
Ecossistema , Pradaria , Humanos , Biodiversidade , Europa (Continente) , União Europeia , Mudança Climática
2.
Sci Rep ; 14(1): 7824, 2024 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570696

RESUMO

Monoculture switchgrass and restored prairie are promising perennial feedstock sources for bioenergy production on the lands unsuitable for conventional agriculture. Such lands often display contrasting topography that influences soil characteristics and interactions between plant growth and soil C gains. This study aimed at elucidating the influences of topography and plant systems on the fate of C originated from switchgrass plants and on its relationships with soil pore characteristics. For that, switchgrass plants were grown in intact soil cores collected from two contrasting topographies, namely steep slopes and topographical depressions, in the fields in multi-year monoculture switchgrass and restored prairie vegetation. The 13C pulse labeling allowed tracing the C of switchgrass origin, which X-ray computed micro-tomography enabled in-detail characterization of soil pore structure. In eroded slopes, the differences between the monoculture switchgrass and prairie in terms of total and microbial biomass C were greater than those in topographical depressions. While new switchgrass increased the CO2 emission in depressions, it did not significantly affect the CO2 emission in slopes. Pores of 18-90 µm Ø facilitated the accumulation of new C in soil, while > 150 µm Ø pores enhanced the mineralization of the new C. These findings suggest that polyculture prairie located in slopes can be particularly beneficial in facilitating soil C accrual and reduce C losses as CO2.


Assuntos
Panicum , Solo , Solo/química , Carbono/química , Dióxido de Carbono , Pradaria , Plantas
3.
Environ Geochem Health ; 46(5): 152, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578358

RESUMO

The Qinghai-Tibet Plateau has low anthropogenic carbon emissions and large carbon stock in its ecosystems. As a crucial region in terrestrial ecosystems responding to climate change, an accurate understanding of the distribution characteristics of soil carbon density holds significance in estimating the soil carbon storage capacity in forests and grasslands. It performs a crucial role in achieving carbon neutrality goals in China. The distribution characteristics of carbon and carbon density in the surface, middle, and deep soil layers are calculated, and the main influencing factors of soil carbon density changes are analyzed. The carbon density in the surface soil ranges from a minimum of 1.62 kg/m2 to a maximum of 52.93 kg/m2. The coefficient of variation for carbon is 46%, indicating a considerable variability in carbon distribution across different regions. There are substantial disparities, with geological background, land use types, and soil types significantly influencing soil organic carbon density. Alpine meadow soil has the highest carbon density compared with other soil types. The distribution of soil organic carbon density at three different depths is as follows: grassland > bare land > forestland > water area. The grassland systems in the Qinghai-Tibet Plateau have considerable soil carbon sink and storage potential; however, they are confronted with the risk of grassland degradation. The grassland ecosystems on the Qinghai-Tibet Plateau harbor substantial soil carbon sinks and storage potential. However, they are at risk of grassland degradation. It is imperative to enhance grassland management, implement sustainable grazing practices, and prevent the deterioration of the grassland carbon reservoirs to mitigate the exacerbation of greenhouse gas emissions and global warming. This highlights the urgency of implementing more studies to uncover the potential of existing grassland ecological engineering projects for carbon sequestration.


Assuntos
Ecossistema , Solo , Tibet , Carbono/análise , Pradaria
4.
Glob Chang Biol ; 30(4): e17264, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38556774

RESUMO

Nutrient enrichment often alters the biomass and species composition of plant communities, but the extent to which these changes are reversible after the cessation of nutrient addition is not well-understood. Our 22-year experiment (15 years for nutrient addition and 7 years for recovery), conducted in an alpine meadow, showed that soil nitrogen concentration and pH recovered rapidly after cessation of nutrient addition. However, this was not accompanied by a full recovery of plant community composition. An incomplete recovery in plant diversity and a directional shift in species composition from grass dominance to forb dominance were observed 7 years after the nutrient addition ended. Strikingy, the historically dominant sedges with low germination rate and slow growth rate and nitrogen-fixing legumes with low germination rate were unable to re-establish after nutrient addition ceased. By contrast, rapid recovery of aboveground biomass was observed after nutrient cessation as the increase in forb biomass only partially compensated for the decline in grass biomass. These results indicate that anthropogenic nutrient input can have long-lasting effects on the structure, but not the soil chemistry and plant biomass, of grassland communities, and that the recovery of soil chemical properties and plant biomass does not necessarily guarantee the restoration of plant community structure. These findings have important implications for the management and recovery of grassland communities, many of which are experiencing alterations in resource input.


Assuntos
Pradaria , Plantas , Biomassa , Poaceae , Solo/química , Nitrogênio/análise , Nutrientes
5.
An Acad Bras Cienc ; 96(1): e20230327, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38597490

RESUMO

Aquatic macrophytes are the main autochthonous component of primary production in the Amazon Basin. Floating meadows of these plants support habitats with highly diverse animal communities. Fishes inhabiting these habitats have been assumed to use a broad range of food items and compose a particular food web. We employed carbon (δ13C) and nitrogen (δ15N) stable isotope analysis to draw the trophic structure of these habitats and to trace the energy flow by its trophic levels. Fishes and other animals from 18 independent macrophyte meadows of a floodplain lake of the Solimões River (Amazonia, Brazil) were analyzed. The food web of macrophyte meadows consists of four trophic levels above autotrophic sources. In general, primary consumers exhibited a broader range of food sources than the upper trophic levels. Some fish species depended on a large number of food sources and at the same time are consumed by several predators. The energy transfer from one trophic level to the next was then mainly accomplished by these species concentrating a high-energy flux and acting as hubs in the food web. The broad range of δ13C values observed indicates that the organisms living in the macrophyte meadows utilize a great diversity of autotrophic sources.


Assuntos
Pradaria , Lagos , Animais , Lagos/química , Ecossistema , Cadeia Alimentar , Peixes , Transferência de Energia
6.
Braz J Biol ; 84: e275828, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38597516

RESUMO

Urban environments present less environmental heterogeneity in relation to the natural ones, affecting the biodiversity of bats and the ecological processes in which they participate. In this way, we will identify how urbanization influences the structure of bat communities in the municipality of Goiânia, Goiás, Brazil. We compared species composition, guilds and bat richness in a gradient that crossed urban, semi-urban and natural areas in the municipality of Goiânia, contained in the Cerrado biome. We captured a total of 775 bats of 16 species distributed in three families. Urban areas had a higher species abundance, while semi-urban areas had a higher species richness. The three types of environments have different compositions, the urban one being more homogeneous, the fauna in these areas is composed of generalist species, which benefit from this process. The diversity present in semi-urban areas is a consequence of the intersection between urban and natural fauna, which is why urban expansion needs to occur in a planned manner to minimize the impacts of this process and ensure the maintenance of biodiversity.


Assuntos
Quirópteros , Humanos , Animais , Urbanização , Brasil , Pradaria , Ecossistema , Biodiversidade
7.
PeerJ ; 12: e17031, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38464755

RESUMO

Background: In a context of long-term highly intensive grazing in grassland ecosystems, a better understanding of how quickly belowground biodiversity responds to grazing is required, especially for soil microbial diversity. Methods: In this study, we conducted a grazing experiment which included the CK (no grazing with a fenced enclosure undisturbed by livestock), light and heavy grazing treatments in a desert steppe in Inner Mongolia, China. Microbial diversity and soil chemical properties (i.e., pH value, organic carbon, inorganic nitrogen (IN, NH4+-N and NO3--N), total carbon, nitrogen, phosphorus, and available phosphorus content) both in rhizosphere and non-rhizosphere soils were analyzed to explore the responses of microbial diversity to grazing intensity and the underlying mechanisms. Results: The results showed that heavy grazing only deceased bacterial diversity in the non-rhizosphere soil, but had no any significant effects on fungal diversity regardless of rhizosphere or non-rhizosphere soils. Bacterial diversity in the rhizosphere soil was higher than that of non-rhizosphere soil only in the heavy grazing treatment. Also, heavy grazing significantly increased soil pH value but deceased NH4+-N and available phosphorus in the non-rhizosphere soil. Spearman correlation analysis showed that soil pH value was significantly negatively correlated with the bacterial diversity in the non-rhizosphere soil. Combined, our results suggest that heavy grazing decreased soil bacterial diversity in the non-rhizosphere soil by increasing soil pH value, which may be due to the accumulation of dung and urine from livestock. Our results highlight that soil pH value may be the main factor driving soil microbial diversity in grazing ecosystems, and these results can provide scientific basis for grassland management and ecological restoration in arid and semi-arid area.


Assuntos
Ecossistema , Solo , Animais , Solo/química , Pradaria , Bactérias , Carbono/análise , Nitrogênio/análise , Gado , Fósforo , Concentração de Íons de Hidrogênio
8.
Sci Rep ; 14(1): 5489, 2024 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448478

RESUMO

Ecological compensation has emerged as a crucial institutional framework for managing the interplay between ecological preservation and economic development in China. This study focuses on the specific case of grassland ecological compensation to investigate the protection of rights and interests of non-governmental subjects. By utilizing data derived from questionnaire responses, this study examines the legal rights, obligations, and responsibilities associated with grassland ecological compensation. Statistical techniques such as Z-distribution, chi-square test, and non-parametric measures of correlation are employed to analyze the collected data, which are presented using tables and graphs. Furthermore, this research evaluates the current state of rights and interests of compensation subjects engaged in ecological compensation practices, aiming to enhance our comprehension and assessment of the extent to which the ecological compensation system safeguards the rights and interests of individuals. The findings show that a substantial number of respondents see current grassland ecological compensation methods in China as reasonable but insufficient, indicating a need for method diversification. There's a clear preference for a shared responsibility model over government-only funding, especially in regions with large grassland areas. This highlights the necessity for adaptable laws and a legal framework that accommodates diverse stakeholder needs. Additionally, the importance of clear property rights is emphasized for sustainable land use. The study suggests legislative reform towards a more equitable and effective approach to grassland conservation, providing valuable recommendations for refining and advancing the ecological compensation system.Author name 1 (Ziqi Liu) mismatch between ms and metadata. We have foolowed metadata. Kindly check and confirm.The metadata is right. Thank you.


Assuntos
Desenvolvimento Econômico , Pradaria , Humanos , China , Coleta de Dados , Ecossistema
9.
Commun Biol ; 7(1): 309, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38467761

RESUMO

Effects of plant diversity on grassland productivity, or overyielding, are found to be robust to nutrient enrichment. However, the impact of cumulative nitrogen (N) addition (total N added over time) on overyielding and its drivers are underexplored. Synthesizing data from 15 multi-year grassland biodiversity experiments with N addition, we found that N addition decreases complementarity effects and increases selection effects proportionately, resulting in no overall change in overyielding regardless of N addition rate. However, we observed a convex relationship between overyielding and cumulative N addition, driven by a shift from complementarity to selection effects. This shift suggests diminishing positive interactions and an increasing contribution of a few dominant species with increasing N accumulation. Recognizing the importance of cumulative N addition is vital for understanding its impacts on grassland overyielding, contributing essential insights for biodiversity conservation and ecosystem resilience in the face of increasing N deposition.


Assuntos
Ecossistema , Pradaria , Nitrogênio , Biodiversidade , Plantas
10.
Glob Chang Biol ; 30(3): e17217, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38456565

RESUMO

Although nitrogen (N) enrichment is known to threaten the temporal stability of aboveground net primary productivity, it remains unclear how it alters that of belowground microbial abundance and whether its impact can be regulated by grassland degradation. Using data from N enrichment experiments at temperate grasslands with no, moderate, severe, and extreme degradation degrees, we quantified the temporal stability of soil microbial abundance (hereafter 'microbial community stability') using the ratio of the mean quantitative PCR to its standard deviation over 4 years. Both bacterial and fungal community stability sharply decreased when N input exceeded 30 g N m-2 year-1 in non-degraded grasslands, whereas a reduction in this threshold occurred in degraded grasslands. Microbial species diversity, species asynchrony, and species associations jointly altered microbial community stability. Interestingly, the linkages between plant and microbial community stability were strengthened in degraded grasslands, suggesting that plants and soil microbes might depend on each other to keep stable communities in harsh environments. Our findings highlighted the importance of grassland degradation in regulating the responses of microbial community stability to N enrichment and provided experimental evidence for understanding the relationships between plant and microbial community stability.


Assuntos
Microbiota , Nitrogênio , Nitrogênio/análise , Pradaria , Solo , Plantas , Ecossistema
11.
Glob Chang Biol ; 30(3): e17235, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38497525

RESUMO

The accelerating pace of climate change has led to unprecedented shifts in surface temperature and precipitation patterns worldwide, with African savannas being among the most vulnerable regions. Understanding the impacts of these extreme changes on ecosystem health, functioning and stability is crucial. This paper focuses on the detection of breakpoints, indicative of shifts in ecosystem functioning, while also determining relevant ecosystem characteristics and climatic drivers that increase susceptibility to these shifts within the semi-arid to arid savanna biome. Utilising a remote sensing change detection approach and rain use efficiency (RaUE) as a proxy for ecosystem functioning, spatial and temporal patterns of breakpoints in the savanna biome were identified. We then employed a novel combination of survival analysis and remote sensing time series analysis to compare ecosystem characteristics and climatic drivers in areas experiencing breakpoints versus areas with stable ecosystem functioning. Key ecosystem factors increasing savanna breakpoint susceptibility were identified, namely higher soil sand content, flatter terrain and a cooler long-term mean temperature during the wet summer season. Moreover, the primary driver of changes in ecosystem functioning in arid savannas, as opposed to wetter tropical savannas, was found to be the increased frequency and severity of rainfall events, rather than drought pressures. This research highlights the importance of incorporating wetness severity metrics alongside drought metrics to comprehensively understand climate-ecosystem interactions leading to abrupt shifts in ecosystem functioning in arid biomes. The findings also emphasise the need to consider the underlying ecosystem characteristics, including soil, topography and vegetation composition, in assessing ecosystem responses to climate change. While this research primarily concentrated on the southern African savanna as a case study, the methodological robustness of this approach enables its application to diverse arid and semi-arid biomes for the assessment of climate-ecosystem interactions that contribute to abrupt shifts.


Assuntos
Ecossistema , Pradaria , Chuva , Estações do Ano , Solo
12.
Plant Biol (Stuttg) ; 26(3): 378-389, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38442014

RESUMO

Precipitation pattern changes may affect plant biodiversity, which could impact ecosystem stability. However, the effects of changes in precipitation regime on ecosystem stability and their potential mechanisms are still unclear. We conducted a 3-year field manipulation experiment with five precipitation treatments (-40%, -20%, 0% (CK), +20% and +40% of ambient growing season precipitation) in a semi-arid desert grassland to examine the effects of precipitation alterations on functional group stability, species asynchrony, and diversity, and the underlying mchanisms of ecosystem stability using structural equation modelling. Alterations in precipitation had different effects on community biomass and functional group biomass. Moreover, ecosystem stability was mainly driven by forb stability (path coefficient = 0.79). Changes in precipitation had significant effects on soil dissolved inorganic N (P < 0.01) further affecting ecosystem stability through species asynchrony (path coefficient = 0.25). Dwarf shrubs had a stabilizing effect on ecosystem stability (path coefficient = 0.32), mainly via deep roots. Ecosystem stability tended to be lower in the -40% (4.72) and +40% (2.74) precipitation treatments. The common reduction in species asynchrony and stability of forb and dwarf shrub functional groups resulted in lower ecosystem stability under the -40% treatment. The lower stability under the +40% treatment might be ascribed to unimproved dwarf shrub stability. Higher dwarf shrub and forb stability contributed to higher ecosystem stability under normal precipitation changes (±20% treatments) and CK. Species diversity was not a crucial driver of ecosystem stability. Our results indicate that precipitation alteration can regulate ecosystem stability via functional group stability (e.g. forb stability, dwarf shrub stability) and species asynchrony in a semiarid desert grassland.


Assuntos
Ecossistema , Pradaria , Biodiversidade , Biomassa , Plantas , Solo
13.
Environ Int ; 185: 108516, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38447452

RESUMO

Climate change is endangering the soil carbon stock of alpine grasslands on the Qinghai-Tibetan Plateau (QTP), but the limited comprehension regarding the mechanisms that sustain carbon storage under hydrothermal changes increases the uncertainty associated with this finding. Here, we examined the relative abundance of soil microbial keystone taxa and their functional potentials, as well as their influence on soil carbon storage with increased precipitation across alpine grasslands on the QTP, China. The findings indicate that alterations in precipitation significantly decreased the relative abundance of the carbon degradation potentials of keystone taxa, such as chemoheterotrophs. The inclusion of keystone taxa and their internal functional potentials in the two best alternative models explained 70% and 63% of the variance in soil organic carbon (SOC) density, respectively. Moreover, we found that changes in chemoheterotrophs had negative effects on SOC density as indicated by a structural equation model, suggesting that some specialized functional potentials of keystone taxa are not conducive to the accumulation of carbon sink. Our study offers valuable insights into the intricate correlation between precipitation-induced alterations in soil microbial keystone taxa and SOC storage, highlighting a rough categorization is difficult to distinguish the hidden threats and the importance of incorporating functional potentials in SOC storage prediction models in response to changing climate.


Assuntos
Carbono , Solo , Solo/química , Carbono/análise , Pradaria , Mudança Climática , China
14.
Ying Yong Sheng Tai Xue Bao ; 35(2): 390-398, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38523096

RESUMO

To explore the coupling of dry-wet seasonal variations of soil respiration with their environmental factors in the alpine meadow under the background of increasing nitrogen (N) deposition, we conducted an experiment in the typical degraded Poa pratensis meadow in the Napahai, Yunnan. There were four treatments, i.e., control (0 g·m-2·a-1), low (5 g·m-2·a-1), medium (10 g·m-2·a-1), and high (15 g·m-2·a-1) levels. We examined the effects of aboveground biomass, plant diversity, and soil physicochemical properties on soil respiration. The results showed that N deposition significantly promoted soil respiration. Compared with that in the control, soil respiration rates increased by 21.9%-53.9% and 27.3%-51.2% in dry and wet seasons, respectively. The maximum value of soil respiration rate was recorded in the medium N treatment. N deposition dramatically elevated aboveground biomass (52.2%-66.4%). Plant diversity declined with increasing N addition levels, with the maximum value (13.5%-24.2%) being recorded in high treatment in wet season. The values of ammonium nitrogen, organic matter, microbial biomass carbon and nitrogen, temperature and moisture in the three N treatments were elevated by 14.3%-333.5% compared with the control, while those of soil pH were decreased by 9.0%-34.6%. Results of the structural equation modelling showed that plant biomass, Shannon diversity, microbial biomass, soil temperature, and moisture showed a positive effect on soil respiration, while bulk density had a negative effect. Soil nitrogen pool and pH were main factors driving soil CO2 emissions, accounting for 55.7% and 45.1% of the variations, respectively. Therefore, short-term atmospheric N deposition stimulated soil respiration primarily via altering soil pH and nitrogen pool components in the degraded alpine meadow.


Assuntos
Ecossistema , Poa , China , Estações do Ano , Pradaria , Solo/química , Nitrogênio/análise , Biomassa , Plantas , Respiração
15.
Elife ; 122024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38497752

RESUMO

Habitat loss and fragmentation per se have been shown to be a major threat to global biodiversity and ecosystem function. However, little is known about how habitat loss and fragmentation per se alters the relationship between biodiversity and ecosystem function (BEF relationship) in the natural landscape context. Based on 130 landscapes identified by a stratified random sampling in the agro-pastoral ecotone of northern China, we investigated the effects of landscape context (habitat loss and fragmentation per se) on plant richness, above-ground biomass, and the relationship between them in grassland communities using a structural equation model. We found that habitat loss directly decreased plant richness and hence decreased above-ground biomass, while fragmentation per se directly increased plant richness and hence increased above-ground biomass. Fragmentation per se also directly decreased soil water content and hence decreased above-ground biomass. Meanwhile, habitat loss decreased the magnitude of the positive relationship between plant richness and above-ground biomass by reducing the percentage of grassland specialists in the community, while fragmentation per se had no significant modulating effect on this relationship. These results demonstrate that habitat loss and fragmentation per se have inconsistent effects on BEF, with the BEF relationship being modulated by landscape context. Our findings emphasise that habitat loss rather than fragmentation per se can weaken the positive BEF relationship by decreasing the degree of habitat specialisation of the community.


Assuntos
Ecossistema , Pradaria , Biomassa , Biodiversidade , China
16.
Ying Yong Sheng Tai Xue Bao ; 35(1): 17-24, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38511435

RESUMO

We established the systematic concept framework of shelterbelt construction, with "shelterbelts" as the core concern in the construction of integrated ecosystems including mountain, river, forest, farmland, lake, grassland and sandy-land in semi-arid wind-sand areas. In the construction of shelterbelts, it is necessary to adhere to the principles of scientific coordination and systematic management, considering the carrying capacity of water resources, the demand for dust control, the greening and beautification effects, as well as the principle of improving economic benefits. In practice, the construction methods should base on the types and temporal-spatial distribution of shelterbelts, following the shelterbelts construction theory and technology to form different structure and service functions, achieving the functional goals of shelterbelts. By focusing on the key elements including people, forests, grass, fields, water, and sand, we put forward the timeliness, practicality, and scientificity of shelterbelt construction, proposing construction methods for farmland shelterbelts, pastureland shelterbelts, windbreak and sand-fixing forests and protective forest around village (city), which might provide production technical support for the high-quality construction of green ecological barrier in northern China.


Assuntos
Ecossistema , Vento , Humanos , Fazendas , Pradaria , Rios , Lagos , Florestas , Conservação dos Recursos Naturais , China
17.
Ying Yong Sheng Tai Xue Bao ; 35(1): 55-61, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38511440

RESUMO

Improving soil fertility is one of the key approaches for ecological restoration of the wind-sand area in northwest Liaoning Province. Taking wind-sand area in northwest Liaoning Province as test object, we conducted a fertilization experiment with treatments of inorganic fertilizer (nitrogen, phosphorus and potassium fertilizers), organic fertilizer, combined application of organic and inorganic fertilizers, and organic fertilizer combined with a biologically organic matrix (γ-polyglutamic acid), and no fertilizer as control. We measured soil organic matter content and extractable cations concentrations, vegetation coverage, and biomass under different fertilization treatments and determine the suitable fertilization mode. The results showed that compared to the control, inorganic fertilizer rapidly increased vegetation coverage and biomass, but high levels of inorganic fertilizer (150 kg N·hm-2) led to soil acidification and Ca2+ leaching. Organic fertilizer increased soil organic matter content, exchangeable K+, Ca2+, and Mg2+ contents, as well as coverage and biomass vegetation, especially combined with γ-polyglutamic acid. Overall, the combination of low levels of inorganic fertilizer (50 kg N·hm-2) and moderate levels of organic fertilizer (30000 kg·hm-2) was the best fertilization practice for the rapid and stable restoration of grassland in wind-sand area. Moreover, the extra addition of γ-polyglutamic acid (60 kg·hm-2)could effectively improve soil fertility.


Assuntos
Agricultura , Solo , Agricultura/métodos , Fertilizantes , Areia , Pradaria , Ácido Poliglutâmico , China , Nitrogênio/análise , Fertilização
18.
Ying Yong Sheng Tai Xue Bao ; 35(1): 25-30, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38511436

RESUMO

We systematically elaborated and compared the spatial scope and landscape changes of Horqin Grassland and Horqin Sand Land from their definitions and ranges. Horqin Grassland is an area with geographical units named after Mongolian tribes, but the boundary is unclear. Horqin Sand Land is also an area that borrows tribal names, but has independent topographic and geomorphic units, and clear boundaries. Horqin Grassland and Horqin Sand Land belong to two spatial regions that are both cross and different. The area and range of Horqin Grassland are larger than that of Horqin Sand Land which has obvious regional characteristics, and is a typical and research object area to study the development and restoration of aeolian desertification. Based on those cognition, we summarized the technologies and example models of comprehensive land management and desertification controlling over the years, and finally sorted out what should be focused on in the future to serve the annihilation war against desertification for Horqin Sand Land.


Assuntos
Conservação dos Recursos Naturais , Areia , Pradaria , China
19.
Ying Yong Sheng Tai Xue Bao ; 35(1): 124-132, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38511448

RESUMO

Microbial necromass carbon (MNC) is an important contributor to soil organic carbon (SOC). Soil carbon storage has increased significantly since the return of farmland to forestland (grassland) on the Loess Plateau. However, the contribution of MNC to SOC accumulation in different vegetation types and the influence factors remain unclear. Herein, we used the biomarker (amino sugar) technique to determine the MNC content and analyzed the influencing factors in 0-5 cm and 5-20 cm soil layers of natural grassland, shrubland (Caragana microphylla), and forestland (Quercus liaodongensis) in the Loess Plateau. The results showed that: 1) the soil pH decreased significantly from grassland to shrubland and then to forestland within the same soil layer. However, the SOC, total nitrogen (TN), microbial biomass carbon (MBC), and microbial biomass nitrogen (MBN) contents showed a reverse trend, with forestland displaying the highest values followed by shrubland and then grassland. The 0-5 cm had significantly higher values than the 5-20 cm depth. 2) The MNC contents varied 0.69-16.41 g·kg-1 in the two soil horizons of the three vegetation types. There were significant increases in the contents of bacterial necromass carbon (BNC), fungal necromass carbon (FNC), and MNC in the 0-5 cm soil from grassland, shrubland to forestland. The contents of MBC were 1.9 times higher in forestland than in shrubland, and 3.2 times higher in shrubland than in grassland. In the 5-20 cm soil layer, the contents of FNC and MBC were significantly higher in the forestland than in the shrubland and grassland. The FNC content was significantly higher than that of the BNC, ranging from 1.16 to 9.83 times greater than the BNC. 3) The contribution of MNC to SOC was 0.6 and 0.7 times higher in shrubland and forestland than in grassland, respectively, with FNC accounting for 15.2%-42.7%, and BNC accounting for 1.4%-7.4%. 4) pH, TN, MBC, and MBN were important factors that influenced MNC accumulation. In summary, the variation in vegetation type altered soil nutrients, microbial activity, and soil pH, resulting in forestland and shrubland being more beneficial to the formation and accumulation of MNC, which was dominated by fungi, compared to grassland.


Assuntos
Carbono , Solo , Solo/química , Carbono/análise , Florestas , China , Nitrogênio/análise , Pradaria
20.
Ying Yong Sheng Tai Xue Bao ; 35(1): 212-218, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38511458

RESUMO

We investigated the effects and mechanisms of nitrogen additions (0, 1, 2, 4, 8, 16, 24, 32 g N·m-2·a-1) on contents of anion and cation in rhizosphere soil, bulk soil, and mixed rhizosphere and bulk soil in the heavily salinized grassland in the agro-pastoral ecotone of North China. The results showed that pH of rhizosphere, mixed and bulk soils decreased significantly with the increases of nitrogen addition levels. Moreover, pH of three soil types under the 32 g N·m-2·a-1 treatment decreased by 1.2, 0.9, and 0.6, respectively, while pH of rhizosphere soil decreased by 0.44 compared with the bulk soil. Na+ content of rhizosphere, mixed and bulk soils significantly decreased, while the NO3- content significantly increased. The proportion of Na+ content in total soluble salt content in rhizosphere soil decreased by 14% and that in bulk soil decreased by 12% after the 32 g N·m-2·a-1 addition. NO3- content increased by 29% in rhizosphere soil and by 26% in bulk soil. There was significant negative correlation between pH and NO3- content, and significant positive correlation between pH and Na+ content. The total soluble salt content of rhizosphere soil under the 32 g N·m-2·a-1 treatment was significantly reduced by 31.5%. Collectedly, nitrogen deposition could reduce soil pH and total soluble salt content of rhizosphere soil and alleviate saline-alkali stress.


Assuntos
Rizosfera , Solo , Solo/química , Pradaria , Nitrogênio/análise , Ânions , Cátions , China , Microbiologia do Solo
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