Coal mining adversely affects soil quality around opencast mines. Therefore, a study was conducted in 2010 and 2011 to assess seasonal and site-specific variations in physical, chemical, and biological properties of s...Coal mining adversely affects soil quality around opencast mines. Therefore, a study was conducted in 2010 and 2011 to assess seasonal and site-specific variations in physical, chemical, and biological properties of soil collected at different distances from mining areas in the Jharia coalfield, India. Throughout the year, the soil in sites near coal mines had a significantly higher bulk density, temperature, elec trical conductivity, and sulfate and heavy metal contents and a significantly lower water-holding capacity, porosity, moisture content, pH, and total nitrogen and available phosphorus contents, compared with the soil collected far from the mines. However, biological properties were site-specific and seasonal. Soil microbial biomass carbon (MBC) and nitrogen (MBN), MBC/MBN, and soil respiration were the highest during the rainy season and the lowest in summer, with the minimum values in the soil near coal mines. A soil quality index revealed a significant effect of heavy metal content on soil biological properties in the coal mining areas.展开更多
An extreme （weather and climate） event does not only mean that an extreme occurs at a location, but more generally it can impact a certainarea and last a certain period of time, which is defined as a regional extrem...An extreme （weather and climate） event does not only mean that an extreme occurs at a location, but more generally it can impact a certainarea and last a certain period of time, which is defined as a regional extreme event （REE） with a certain impacted area and duration. The conceptof REE has been defined to allow mainly objective assessment of the events without a pre-determined boundary and duration. This paper reviewsthe studies on REEs published during the past 20 years, especially recent years. Mainly in view of methodology, these studies can be divided intothree types studies focusing on spatial simultaneity, studies focusing on temporal persistence, and studies identifying REEs. The methodsidentifying REEs include two kinds, e.g., type-I methods stressing REE＇s temporal persistence within a relatively certain area and type-IImethods focusing on catching a complete REE. Identification methods proposed in this paper could provide valuable information for variouspurposes, such as real-time monitoring, estimating long-term changes, mechanism diagnosis, forecasting study and even attribution analysis.Research on REEs is important for objectively defining extreme weather and climate events, which depends on the spatial and temporal scales ofinterest. Such an objective definition will support ongoing climate monitoring and improve the assessment of how regional extreme events havechanged over time.展开更多
Three ethylene diurea （EDU） concentrations （0, 150 and 300 mg/L） were used to evaluate the negative impact of ozone （O3） on two cultivars of Trifoliurn repens L. cv. Vardan and Bundel grown under natural field c...Three ethylene diurea （EDU） concentrations （0, 150 and 300 mg/L） were used to evaluate the negative impact of ozone （O3） on two cultivars of Trifoliurn repens L. cv. Vardan and Bundel grown under natural field conditions in a suburban area of Varanasi, India. Mean O3 concentrations varied from 30.3 to 46.6 μg/L during the experimental period. Higher photosynthetic pigments and ascorhic acid concentrations were noticed in both EDU-treated cultivars over non-EDU-treated ones, but a reverse trend was found for lipid peroxidation. Growth parameters and biomass also showed increments under EDU treatment of both cultivars. The ratio of variable fluorescence to maximum fluorescence increased significantly in Vardan but not in Bundel upon EDU treatment. Results revealed that EDU concentration of 300 mg/L was more effective to combat the oxidative stress as well as protecting plants from O3 injury symptoms. The test cultivar Vardan is relatively sensitive to O3, thereby can be used as a bioindicator of O3 pollution in areas having higher O3 concentrations. Results also indicated that Bundel has more efficient antioxidant defense system than Vardan and hence was more tolerant to O3 stress.展开更多
Along with the concept, the method of assessing the vulnerability is becoming more and more diversified in many directions and fields. In general, these methods can be classified into two groups： （i） direct-qualita...Along with the concept, the method of assessing the vulnerability is becoming more and more diversified in many directions and fields. In general, these methods can be classified into two groups： （i） direct-qualitative （survey methods, integrated map ...） and （ii） indirectly-quantitative （method index）. The set of indicator plays a very important role in the successful application to any method and brings reliable results. Each basin or area with different natural geography, economics and society and so on, requires a different set of indicator. However, assessing any river basin in Vietnam needs the basic indicator. This study will establish the basic indicator for the construction of flood vulnerability index in Vietnam.展开更多
Anthropogenic activities have become more and more important in characterizing the landscape, but their impacts are still restricted by natural environments. This paper discusses the interactions of anthropogenic acti...Anthropogenic activities have become more and more important in characterizing the landscape, but their impacts are still restricted by natural environments. This paper discusses the interactions of anthropogenic activity, vegetation activity and topography through describing the spatial distribution of land cover and vegetation activity (represented by Normalized Difference Vegetation Index, NDVI) along topographic gradient in a mountainous area of southwestern China. Our results indicate that the existing landscape pattern is controlled by anthropogenic activities as well as topographic factors. Intensive anthropogenic activities mainly occur in areas with relatively low elevation, gentle and concave slopes, as these areas are easy and convenient to attain for human. Because of the destruction by human, some land cover types (mainly grassland and shrub) are only found in relatively harsher environments. This study also finds that topographic wetness index (W) used in other places only reflects runoff generation capacity, but not indicate the real spatial pattern of soil water content in this area. The relationships between NDVI and W, and NDVI and length slope factor (LSF) show that runoff and erosion have complex effects on vegetation activity. Greater values of W and LSF will lead to stronger capacity to produce runoff and transport sediment, and thereby increase soil water content and soil deposition, whereas beyond a certain threshold runoff and erosion are so strong that they would destruct vegetation growth. This study provides information needed to successfully restore native vegetation, improve land management, and promote sustainable development in mountainous areas, especially for developing regions.展开更多
The coast of Morocco is,in many locations, physically and socio-economically vulnerable to accelerated sea-level rise,due to its low topography and its high ecological,economic and touristic values. Assessment of the ...The coast of Morocco is,in many locations, physically and socio-economically vulnerable to accelerated sea-level rise,due to its low topography and its high ecological,economic and touristic values. Assessment of the potential land loss by inundation and erosion,based on a modeling approach and Geographical Information Systems(GIS),has enabled to identify both locations and the socioeconomic sectors that展开更多
Detarium senegalense J. F. Gmel., of the family of Fabaceae is one of the most exploited tree species in Togo. However, there are only few scientific studies on the distribution of this specie. This study is a contrib...Detarium senegalense J. F. Gmel., of the family of Fabaceae is one of the most exploited tree species in Togo. However, there are only few scientific studies on the distribution of this specie. This study is a contribution to the promotion of multi-purpose tree species in Togo with particular emphasis on a better knowledge of Detarium senegalense. It provides data on the ecology of the specie and his state of regeneration. The data on the specie are based on sample plots in the areas identified as hosts of the specie in Togo. A total of 77 circular plots of 1000 m2 (17.8 m radius) were established in ecological zones II, IV and V of Togo. The dendrometric parameters identified are: the total height and diameter at breast height (DBH) of Detarium senegalense and of all species found in each plot. Detarium senegalense trees of DBH < 10 cm are considered as potential regenerations. Detarium senegalense is more abundant in zones IV (forest area), followed by zone II. In zone V, Detarium senegalense is located only in the forest of “Have”. The structure of Detarium senegalense has a bell-shaped distribution with predominance of trees with large and intermediate diameters ranging between 30 and 70 cm. Trees of small DBH (Detarium senegalense occurs. This indicates a low regeneration rate of the specie. However, the structure of all species inventoried has a negative exponential distribution with predominance of small diameter trees. The sustainable management of Detarium senegalense in the forest can only be secured through a sustainable harvesting of seeds and actives promotion of natural regeneration.展开更多
Understanding the characteristics of extreme rainfall is crucial for effective flood management planning, as it enables the incorporation of insights from past extreme rainfall patterns and their spatiotemporal distri...Understanding the characteristics of extreme rainfall is crucial for effective flood management planning, as it enables the incorporation of insights from past extreme rainfall patterns and their spatiotemporal distribution. This work investigated the changes in the frequency and pattern of extreme rainfall over Uganda, using daily datasets sourced from Climate Hazard Group InfraRed Precipitation with Station (CHIRPS-v2) for the period 1981 to 2022. The study utilized the extreme weather Indices provided by the Expert Team on Climate Change Detection and Indices (ETCCDI). Attention was directed towards September to November (SON) rainfall season with precise analysis of four indices (Rx1day, Rx5day, R95p, and R99p). The Sequential Mann-Kendall (SQMK) non-parametric test was applied to identify abrupt changes in SON extreme rainfall trends. Results showed that October consistently recorded the highest count of extreme rainfall days across all four indices. The long-term analysis revealed fluctuations in extreme rainfall events across years, with certain periods exhibiting heightened intensity. The analysis portrayed a shift in the decadal variations and region-specific distribution of extreme rainfall, with Eastern Uganda and areas around Lake Victoria standing out compared to other regions. The findings further revealed an increase in extreme rainfall for all indices in the recent decade (2011-2022) with 2019/2020 standing out as the extreme years of SON for the study period. While trendlines suggested a slight increase in intense daily rainfall events, the SQMK tests revealed statistical significance in the trend of prolonged periods of intense daily rainfall. This study contributes to the understanding of the spatiotemporal variability and trends of extreme rainfall events over Uganda during the SON season, which is crucial for the assessment of climate change impacts and adaptation strategies. It provides valuable information for seasonal extreme rainfall forecasting, development of early warning systems, flood risk management, and disaster preparedness plans.展开更多
Aims Government policy in Ireland is to increase the national forest cover from the current 10%to 18%of the total land area by 2020.This represents a major land use change that is expected to impact on the national ca...Aims Government policy in Ireland is to increase the national forest cover from the current 10%to 18%of the total land area by 2020.This represents a major land use change that is expected to impact on the national carbon(C)stocks.While the C stocks of ecosystem bio-mass and soils of Irish grasslands and coniferous forests have been quantified,little work has been done to assess the impact of broad-leaf afforestation on C stocks.Methods In this study,we sampled a chronosequence of ash(Fraxinus excel-sior)forests aged 12,20,27,40 and 47 years on brown earth soils.A grassland site,representative of the pre-afforestation land use,was sampled as a control.Important Findings Our results show that there was a significant decline(P<0.05)in the carbon density of the soil(0-30 cm)following afforestation from the grassland(90.2 Mg C ha^(−1))to the 27-year-old forest(66.7 Mg C ha^(−1)).Subsequently,the forest soils switched from being a C source to a C sink and began to sequester C to 71.3 Mg C ha^(−1) at the 47-year-old forest.We found the amount of C stored in the above-and belowground biomass increased with age of the forest stands and offset the amount of C lost from the soil.The amount of C stored in the above-and belowground biomass increased on average by 1.83 Mg C ha^(−1) year^(−1).The increased storage of C in the biomass led to an increase in the total ecosystem C,from 90.2 Mg C ha^(−1) at the grassland site to 162.6 Mg C ha^(−1) at the 47-year-old forest.On a national scale,projected rates of ash afforestation to the year 2020 may cause a loss of 290752 Mg C from the soil compared to 2525936 Mg C sequestered into the tree biomass.The effects of harvesting and reforestation may further modify the development of ecosystem C stocks over an entire ash rotation.展开更多
Background The mangrove ecosystem has the highest carbon sink potential which significantly contributes to bringing carbon neutrality.Understanding the carbon stock dynamics along the age of forest stands in the mangr...Background The mangrove ecosystem has the highest carbon sink potential which significantly contributes to bringing carbon neutrality.Understanding the carbon stock dynamics along the age of forest stands in the mangrove forest ecosystem is of significance for managing the forests and their carbon accumulation.This study aimed to estimate the forest structural attributes,biomass and total ecosystem carbon stock(TECS)of old natural(age>50 years)and young planted(age~20 years)mangrove forest stands at Bichitrapur Mangrove Reserve Forest in eastern coast of India.We also attempted to understand the interrelationship of structural attributes,biomass and soil properties in the mangrove forests.To achieve the results,twenty random plots were established(size:20 m×25 m)and suitable allometric equations along with species-specific wood density values were used to estimate the biomass and carbon stock.Results Altogether,29 plant species(18 exclusive and 11 associate species)were recorded.The mean total biomass(±SE)and soil organic carbon(at 30 cm depth)were 165.31±20.89 t ha^(-1)and 40.20±1.24 t C ha^(-1)for young stands,and 586.12±56.74 t ha^(-1)and 49.68±2.39 t C ha^(-1)for old stands,respectively.Among mangrove species,Avicennia marina contributed the highest vegetation biomass in both forest stands(59.72 t ha^(-1)and 262.28 t ha^(-1)in young and old stands,respectively),followed by Avicennia officinalis(35.05 t ha^(-1))and Sonneratia apetala(26.09 t ha^(-1))in young stand and Avicennia alba(169.28 t ha^(-1))and Avicennia officinalis(115.58 t ha^(-1))in old stand.The mean TECS was 235.62±27.34 t C ha^(-1).The contribution of vegetation and soil to TECS was 63%and 37%in the young stand,whereas in the old stand it was 83%and 17%,respectively.The correlation analyses revealed that mean stand height(r=0.87),basal area(r=0.99),soil nitrogen(r=0.76),potassium(r=0.78),and carbon(r=0.80)were significantly positively correlated with total biomass at p<0.01.Conclusions Our results demonstrate that old mangrove forest stands store substantially high carbon stock than young planted forest stands,implying the role of forest age in determining the carbon storage potential of mangrove ecosystems.展开更多
A troubling feedback loop, where drier soil contributes to hotter climates, has been widely recognized.This study, drawing on climate model simulations, reveals that maintaining current global soil moisture levels cou...A troubling feedback loop, where drier soil contributes to hotter climates, has been widely recognized.This study, drawing on climate model simulations, reveals that maintaining current global soil moisture levels could significantly alleviate 32.9% of land warming under low-emission scenarios. This action could also postpone reaching critical warming thresholds of 1.5 °C and 2.0 °C by at least a decade. Crucially,preserving soil moisture at current levels could prevent noticeable climate change impacts across 42%of the Earth's land, a stark deviation from projections suggesting widespread impacts before the 2060s.To combat soil drying, afforestation in mid-to-low latitude regions within the next three decades is proposed as an effective strategy to increase surface water availability. This underscores the substantial potential of nature-based solutions for managing soil moisture, benefiting both climate change mitigation and ecological enhancement.展开更多
This study aimed to evaluate the antioxidant,antidiabetic,and anticholinesterase activities of Buchanania lanzan Spreng seeds.The therapeutic significance of phytochemicals,minerals,and nutrition were quantified.Hydro...This study aimed to evaluate the antioxidant,antidiabetic,and anticholinesterase activities of Buchanania lanzan Spreng seeds.The therapeutic significance of phytochemicals,minerals,and nutrition were quantified.Hydroalcohol-extract(HABL)possessed the highest phenol contents demonstrated superior inhibitory potential against oxidants in DPPH,CAP-e,and imparted total antioxidant capacity in ORAC test.HABL exhibited mixed-competitive inhibition against α-amylase and α-glucosidase.HABL exhibited mixed-competitive and competitive inhibition against acetyl-,and butyryl-cholinesterase.Seeds were a rich source of minerals,amino acids,protein,carbohydrates,volatile oil,and energy content.Reported Vit B3 and B6 in seeds were responsible for brain function,and neurotransmitter-synthesis.HPLC quantified phenols(gallic acid,chlorogenic acid,caffeic acid,rutin,and quercetin),and GC-MS identified(Catechol,2-Hydroxy-5-methylbenzaldehyde,Hexadecanoic acid,methyl ester,n-Hexadecanoic acid,Hexadecanoic acid,ethyl ester,8-Octadecenoic acid,methyl ester,9,12-Octadecadienoic acid,ethyl ester,(E)-9-Octadecenoic acid ethyl ester,Heptadecanoic acid,15-methyl-,ethyl ester,Hexadecanoic acid,2-hydroxy-1-(hydroxymethyl)ethyl ester,9-Octadecenoic acid(Z)-,2-hydroxy-1-(hydroxymethyl)ethyl,and β-Sitosterol)in HABL exhibited antioxidant,antidiabetic,and anticholinesterase activities.B.lanzan seeds are given adequate attention for making medicines and dietary supplements in the pharmaceutical and nutraceutical industries.展开更多
基金the Ministry of Coal, Government of India and the University Grant Commission, New Delhi, India for financial assistance
文摘Coal mining adversely affects soil quality around opencast mines. Therefore, a study was conducted in 2010 and 2011 to assess seasonal and site-specific variations in physical, chemical, and biological properties of soil collected at different distances from mining areas in the Jharia coalfield, India. Throughout the year, the soil in sites near coal mines had a significantly higher bulk density, temperature, elec trical conductivity, and sulfate and heavy metal contents and a significantly lower water-holding capacity, porosity, moisture content, pH, and total nitrogen and available phosphorus contents, compared with the soil collected far from the mines. However, biological properties were site-specific and seasonal. Soil microbial biomass carbon (MBC) and nitrogen (MBN), MBC/MBN, and soil respiration were the highest during the rainy season and the lowest in summer, with the minimum values in the soil near coal mines. A soil quality index revealed a significant effect of heavy metal content on soil biological properties in the coal mining areas.
文摘An extreme （weather and climate） event does not only mean that an extreme occurs at a location, but more generally it can impact a certainarea and last a certain period of time, which is defined as a regional extreme event （REE） with a certain impacted area and duration. The conceptof REE has been defined to allow mainly objective assessment of the events without a pre-determined boundary and duration. This paper reviewsthe studies on REEs published during the past 20 years, especially recent years. Mainly in view of methodology, these studies can be divided intothree types studies focusing on spatial simultaneity, studies focusing on temporal persistence, and studies identifying REEs. The methodsidentifying REEs include two kinds, e.g., type-I methods stressing REE＇s temporal persistence within a relatively certain area and type-IImethods focusing on catching a complete REE. Identification methods proposed in this paper could provide valuable information for variouspurposes, such as real-time monitoring, estimating long-term changes, mechanism diagnosis, forecasting study and even attribution analysis.Research on REEs is important for objectively defining extreme weather and climate events, which depends on the spatial and temporal scales ofinterest. Such an objective definition will support ongoing climate monitoring and improve the assessment of how regional extreme events havechanged over time.
文摘Three ethylene diurea （EDU） concentrations （0, 150 and 300 mg/L） were used to evaluate the negative impact of ozone （O3） on two cultivars of Trifoliurn repens L. cv. Vardan and Bundel grown under natural field conditions in a suburban area of Varanasi, India. Mean O3 concentrations varied from 30.3 to 46.6 μg/L during the experimental period. Higher photosynthetic pigments and ascorhic acid concentrations were noticed in both EDU-treated cultivars over non-EDU-treated ones, but a reverse trend was found for lipid peroxidation. Growth parameters and biomass also showed increments under EDU treatment of both cultivars. The ratio of variable fluorescence to maximum fluorescence increased significantly in Vardan but not in Bundel upon EDU treatment. Results revealed that EDU concentration of 300 mg/L was more effective to combat the oxidative stress as well as protecting plants from O3 injury symptoms. The test cultivar Vardan is relatively sensitive to O3, thereby can be used as a bioindicator of O3 pollution in areas having higher O3 concentrations. Results also indicated that Bundel has more efficient antioxidant defense system than Vardan and hence was more tolerant to O3 stress.
文摘Along with the concept, the method of assessing the vulnerability is becoming more and more diversified in many directions and fields. In general, these methods can be classified into two groups： （i） direct-qualitative （survey methods, integrated map ...） and （ii） indirectly-quantitative （method index）. The set of indicator plays a very important role in the successful application to any method and brings reliable results. Each basin or area with different natural geography, economics and society and so on, requires a different set of indicator. However, assessing any river basin in Vietnam needs the basic indicator. This study will establish the basic indicator for the construction of flood vulnerability index in Vietnam.
基金the National Natural Science Foundation of China (40621061)the Project of Chinese Academy of Sciences (KZCX2-XB2-02-31) for their financial support
文摘Anthropogenic activities have become more and more important in characterizing the landscape, but their impacts are still restricted by natural environments. This paper discusses the interactions of anthropogenic activity, vegetation activity and topography through describing the spatial distribution of land cover and vegetation activity (represented by Normalized Difference Vegetation Index, NDVI) along topographic gradient in a mountainous area of southwestern China. Our results indicate that the existing landscape pattern is controlled by anthropogenic activities as well as topographic factors. Intensive anthropogenic activities mainly occur in areas with relatively low elevation, gentle and concave slopes, as these areas are easy and convenient to attain for human. Because of the destruction by human, some land cover types (mainly grassland and shrub) are only found in relatively harsher environments. This study also finds that topographic wetness index (W) used in other places only reflects runoff generation capacity, but not indicate the real spatial pattern of soil water content in this area. The relationships between NDVI and W, and NDVI and length slope factor (LSF) show that runoff and erosion have complex effects on vegetation activity. Greater values of W and LSF will lead to stronger capacity to produce runoff and transport sediment, and thereby increase soil water content and soil deposition, whereas beyond a certain threshold runoff and erosion are so strong that they would destruct vegetation growth. This study provides information needed to successfully restore native vegetation, improve land management, and promote sustainable development in mountainous areas, especially for developing regions.
文摘The coast of Morocco is,in many locations, physically and socio-economically vulnerable to accelerated sea-level rise,due to its low topography and its high ecological,economic and touristic values. Assessment of the potential land loss by inundation and erosion,based on a modeling approach and Geographical Information Systems(GIS),has enabled to identify both locations and the socioeconomic sectors that
文摘Detarium senegalense J. F. Gmel., of the family of Fabaceae is one of the most exploited tree species in Togo. However, there are only few scientific studies on the distribution of this specie. This study is a contribution to the promotion of multi-purpose tree species in Togo with particular emphasis on a better knowledge of Detarium senegalense. It provides data on the ecology of the specie and his state of regeneration. The data on the specie are based on sample plots in the areas identified as hosts of the specie in Togo. A total of 77 circular plots of 1000 m2 (17.8 m radius) were established in ecological zones II, IV and V of Togo. The dendrometric parameters identified are: the total height and diameter at breast height (DBH) of Detarium senegalense and of all species found in each plot. Detarium senegalense trees of DBH < 10 cm are considered as potential regenerations. Detarium senegalense is more abundant in zones IV (forest area), followed by zone II. In zone V, Detarium senegalense is located only in the forest of “Have”. The structure of Detarium senegalense has a bell-shaped distribution with predominance of trees with large and intermediate diameters ranging between 30 and 70 cm. Trees of small DBH (Detarium senegalense occurs. This indicates a low regeneration rate of the specie. However, the structure of all species inventoried has a negative exponential distribution with predominance of small diameter trees. The sustainable management of Detarium senegalense in the forest can only be secured through a sustainable harvesting of seeds and actives promotion of natural regeneration.
文摘Understanding the characteristics of extreme rainfall is crucial for effective flood management planning, as it enables the incorporation of insights from past extreme rainfall patterns and their spatiotemporal distribution. This work investigated the changes in the frequency and pattern of extreme rainfall over Uganda, using daily datasets sourced from Climate Hazard Group InfraRed Precipitation with Station (CHIRPS-v2) for the period 1981 to 2022. The study utilized the extreme weather Indices provided by the Expert Team on Climate Change Detection and Indices (ETCCDI). Attention was directed towards September to November (SON) rainfall season with precise analysis of four indices (Rx1day, Rx5day, R95p, and R99p). The Sequential Mann-Kendall (SQMK) non-parametric test was applied to identify abrupt changes in SON extreme rainfall trends. Results showed that October consistently recorded the highest count of extreme rainfall days across all four indices. The long-term analysis revealed fluctuations in extreme rainfall events across years, with certain periods exhibiting heightened intensity. The analysis portrayed a shift in the decadal variations and region-specific distribution of extreme rainfall, with Eastern Uganda and areas around Lake Victoria standing out compared to other regions. The findings further revealed an increase in extreme rainfall for all indices in the recent decade (2011-2022) with 2019/2020 standing out as the extreme years of SON for the study period. While trendlines suggested a slight increase in intense daily rainfall events, the SQMK tests revealed statistical significance in the trend of prolonged periods of intense daily rainfall. This study contributes to the understanding of the spatiotemporal variability and trends of extreme rainfall events over Uganda during the SON season, which is crucial for the assessment of climate change impacts and adaptation strategies. It provides valuable information for seasonal extreme rainfall forecasting, development of early warning systems, flood risk management, and disaster preparedness plans.
基金Irish Council for Forest Research and Development(COFORD),Department of Agriculture Fisheries and Food(DAAF)Science,Technology,Research and Innovation for the Environment(STRIVE)programme 2007-2013(2008-CCRP-1.1A),Irish Environmental Protection Agency(EPA).
文摘Aims Government policy in Ireland is to increase the national forest cover from the current 10%to 18%of the total land area by 2020.This represents a major land use change that is expected to impact on the national carbon(C)stocks.While the C stocks of ecosystem bio-mass and soils of Irish grasslands and coniferous forests have been quantified,little work has been done to assess the impact of broad-leaf afforestation on C stocks.Methods In this study,we sampled a chronosequence of ash(Fraxinus excel-sior)forests aged 12,20,27,40 and 47 years on brown earth soils.A grassland site,representative of the pre-afforestation land use,was sampled as a control.Important Findings Our results show that there was a significant decline(P<0.05)in the carbon density of the soil(0-30 cm)following afforestation from the grassland(90.2 Mg C ha^(−1))to the 27-year-old forest(66.7 Mg C ha^(−1)).Subsequently,the forest soils switched from being a C source to a C sink and began to sequester C to 71.3 Mg C ha^(−1) at the 47-year-old forest.We found the amount of C stored in the above-and belowground biomass increased with age of the forest stands and offset the amount of C lost from the soil.The amount of C stored in the above-and belowground biomass increased on average by 1.83 Mg C ha^(−1) year^(−1).The increased storage of C in the biomass led to an increase in the total ecosystem C,from 90.2 Mg C ha^(−1) at the grassland site to 162.6 Mg C ha^(−1) at the 47-year-old forest.On a national scale,projected rates of ash afforestation to the year 2020 may cause a loss of 290752 Mg C from the soil compared to 2525936 Mg C sequestered into the tree biomass.The effects of harvesting and reforestation may further modify the development of ecosystem C stocks over an entire ash rotation.
文摘Background The mangrove ecosystem has the highest carbon sink potential which significantly contributes to bringing carbon neutrality.Understanding the carbon stock dynamics along the age of forest stands in the mangrove forest ecosystem is of significance for managing the forests and their carbon accumulation.This study aimed to estimate the forest structural attributes,biomass and total ecosystem carbon stock(TECS)of old natural(age>50 years)and young planted(age~20 years)mangrove forest stands at Bichitrapur Mangrove Reserve Forest in eastern coast of India.We also attempted to understand the interrelationship of structural attributes,biomass and soil properties in the mangrove forests.To achieve the results,twenty random plots were established(size:20 m×25 m)and suitable allometric equations along with species-specific wood density values were used to estimate the biomass and carbon stock.Results Altogether,29 plant species(18 exclusive and 11 associate species)were recorded.The mean total biomass(±SE)and soil organic carbon(at 30 cm depth)were 165.31±20.89 t ha^(-1)and 40.20±1.24 t C ha^(-1)for young stands,and 586.12±56.74 t ha^(-1)and 49.68±2.39 t C ha^(-1)for old stands,respectively.Among mangrove species,Avicennia marina contributed the highest vegetation biomass in both forest stands(59.72 t ha^(-1)and 262.28 t ha^(-1)in young and old stands,respectively),followed by Avicennia officinalis(35.05 t ha^(-1))and Sonneratia apetala(26.09 t ha^(-1))in young stand and Avicennia alba(169.28 t ha^(-1))and Avicennia officinalis(115.58 t ha^(-1))in old stand.The mean TECS was 235.62±27.34 t C ha^(-1).The contribution of vegetation and soil to TECS was 63%and 37%in the young stand,whereas in the old stand it was 83%and 17%,respectively.The correlation analyses revealed that mean stand height(r=0.87),basal area(r=0.99),soil nitrogen(r=0.76),potassium(r=0.78),and carbon(r=0.80)were significantly positively correlated with total biomass at p<0.01.Conclusions Our results demonstrate that old mangrove forest stands store substantially high carbon stock than young planted forest stands,implying the role of forest age in determining the carbon storage potential of mangrove ecosystems.
基金supported by the National Natural Science Foundation of China (42288101, 42175053)the National Key Research and Development Program of China (2022YFF0801703)supported by Swedish BECC and MERGE,the Swedish Research Council VR (2021-02163, 2022-06011)。
文摘A troubling feedback loop, where drier soil contributes to hotter climates, has been widely recognized.This study, drawing on climate model simulations, reveals that maintaining current global soil moisture levels could significantly alleviate 32.9% of land warming under low-emission scenarios. This action could also postpone reaching critical warming thresholds of 1.5 °C and 2.0 °C by at least a decade. Crucially,preserving soil moisture at current levels could prevent noticeable climate change impacts across 42%of the Earth's land, a stark deviation from projections suggesting widespread impacts before the 2060s.To combat soil drying, afforestation in mid-to-low latitude regions within the next three decades is proposed as an effective strategy to increase surface water availability. This underscores the substantial potential of nature-based solutions for managing soil moisture, benefiting both climate change mitigation and ecological enhancement.
基金Financial support for this work was provided by the Forest,Environment and Climate Change Department,Govt.of Odisha,Bhubaneswar,India(Grant no.R&D-25/21Dt.13-04-2021).
文摘This study aimed to evaluate the antioxidant,antidiabetic,and anticholinesterase activities of Buchanania lanzan Spreng seeds.The therapeutic significance of phytochemicals,minerals,and nutrition were quantified.Hydroalcohol-extract(HABL)possessed the highest phenol contents demonstrated superior inhibitory potential against oxidants in DPPH,CAP-e,and imparted total antioxidant capacity in ORAC test.HABL exhibited mixed-competitive inhibition against α-amylase and α-glucosidase.HABL exhibited mixed-competitive and competitive inhibition against acetyl-,and butyryl-cholinesterase.Seeds were a rich source of minerals,amino acids,protein,carbohydrates,volatile oil,and energy content.Reported Vit B3 and B6 in seeds were responsible for brain function,and neurotransmitter-synthesis.HPLC quantified phenols(gallic acid,chlorogenic acid,caffeic acid,rutin,and quercetin),and GC-MS identified(Catechol,2-Hydroxy-5-methylbenzaldehyde,Hexadecanoic acid,methyl ester,n-Hexadecanoic acid,Hexadecanoic acid,ethyl ester,8-Octadecenoic acid,methyl ester,9,12-Octadecadienoic acid,ethyl ester,(E)-9-Octadecenoic acid ethyl ester,Heptadecanoic acid,15-methyl-,ethyl ester,Hexadecanoic acid,2-hydroxy-1-(hydroxymethyl)ethyl ester,9-Octadecenoic acid(Z)-,2-hydroxy-1-(hydroxymethyl)ethyl,and β-Sitosterol)in HABL exhibited antioxidant,antidiabetic,and anticholinesterase activities.B.lanzan seeds are given adequate attention for making medicines and dietary supplements in the pharmaceutical and nutraceutical industries.
