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Inventory and Distribution of Benthic Macroinvertebrates, Indicators of Water Quality in Four Forested Watercourses in Centre Region of Cameroon
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作者 Eric B. Biram à Ngon Sylvie B. Chinche +9 位作者 Josephine Ndjama Jean Dzavi Donald L. Nyame Mbia Mathias Nwaha Serge R. Gwos Nhiomock Blaise R. Mboye Ivone L. Tchaouapi Ulrich Tchouta Chamberline Ngalamou Samuel Foto Menbohan 《Open Journal of Ecology》 2024年第4期381-394,共14页
The inventory of benthic macroinvertebrate species was carried out in some streams of the Mefou catchment area, from August 2021 to August 2022, in order to determine the biological groups that make up the population ... The inventory of benthic macroinvertebrate species was carried out in some streams of the Mefou catchment area, from August 2021 to August 2022, in order to determine the biological groups that make up the population and characterise these environments. The dataset acquired during this study made it possible to update the existing database and contribute to the knowledge of the biological groups associated in these environments, and to provide additional information on the existing ones in relation to bioindication. Overall 80 families were identified and, on the basis of frequencies of occurrence greater than 75%, 22 families were retained as potential biological indicators. The remarkable diversity of insects and the low abundance of Diptera reflect the low degradation of environments and the good quality of water. The high diversity indices obtained reflect the maintenance of the favourable ecological conditions that favours the development of a balanced and, integrated biological community capable of adapting to changes. 展开更多
关键词 Benthic Macroinvertebrates BIOINDICATORS Biological Quality Forest Watercourse Cameroon
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Modelling and Mapping Likely Soil Rutting Occurrences across Forested Areas
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作者 Daniel Snow Elizabeth White +1 位作者 Nana Agyei O. Afriyie Paul A. Arp 《Journal of Geographic Information System》 2024年第6期397-417,共21页
This article addresses where ruts are likely to occur during in-field forest operations. This was done by inspecting high-resolution surface images across New Brunswick (NB) and elsewhere to mark where ruts have (1) a... This article addresses where ruts are likely to occur during in-field forest operations. This was done by inspecting high-resolution surface images across New Brunswick (NB) and elsewhere to mark where ruts have (1) and have not (0) occurred in harvested cutblocks. This marking revealed 1) where off-road operations were likely done on moist to wet and unfrozen soils;and 2) whether the ruts so incurred were water-logged at the time of imaging. Through geospatial processing of the NB-wide digital elevation model (DEM, available at 1 m resolution), the following attributes were added to each of the marked rut and no-rut locations: 1) the cartographic depth-to-water (DTW) as referenced to the nearest flow channels with >1 and >4 ha upslope flow accumulation areas (FA);2) the topographic position index (TPI) in reference to the mean annulus elevation 50 m away from each DEM cell;3) mean slope and curvatures within each cell-surrounding 10-m circle;4) the terrain wetness index (TWI);5) soil association type according to the NB forest soil map, adjusted for NB’s most recent hydrographic network delineations for waterbodies and wetlands. Subjecting these data to logistic regression analysis revealed that image-located off-road rutting occurred at about 90% probability in water-accumulating zones where TPI is <0 m and DTW is <1 m. Using slope, curvature, TWI, and soil type as additional rut occurrence predictors did not affect this zonation significantly. 展开更多
关键词 Forest Operations OFF-ROAD Satellite Imageries Rut Locations Point Shapefiles Logistic Regression Analysis Rut Occurrence Projections
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Ecosystem carbon storage and sink/source of temperate forested wetlands in Xiaoxing’anling, northeast China 被引量:12
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作者 Biao Wang Changcheng Mu +3 位作者 Huicui Lu Na Li Yan Zhang Li Ma 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第3期839-849,共11页
Wetlands play an important role in the global carbon cycle, but there are still considerable uncertainties in the estimation of wetland carbon storage and a dispute on whether wetlands are carbon sources or carbon sin... Wetlands play an important role in the global carbon cycle, but there are still considerable uncertainties in the estimation of wetland carbon storage and a dispute on whether wetlands are carbon sources or carbon sinks. Xiaoxing’anling are one of several concentrated distribution areas of forested wetland in China, but the carbon storage and carbon sink/source of forested wetlands in this area is unclear. We measured the ecosystem carbon storage (vegetation and soil), annual net carbon sequestration of vegetation and annual carbon emissions of soil heterotrophic respiration of five typical forested wetland types (alder swamp, white birch swamp, larch swamp, larch fen, and larch bog) distributed along a moisture gradient in this area in order to reveal the spatial variations of their carbon storage and quantitatively evaluate their position as carbon sink or source according to the net carbon balance of the ecosystems. The results show that the larch fen had high carbon storage (448.8 t ha^(−1)) (6.8% higher than the larch bog and 10.5–30.1% significantly higher than other three wetlands (P < 0.05), the white birch swamp and larch bog were medium carbon storage ecosystems (406.3 and 420.1 t ha^(−1)) (12.4–21.8% significantly higher than the other two types (P < 0.0 5), while the alder swamp and larch swamp were low in carbon storage (345.0 and 361.5 t ha^(−1), respectively). The carbon pools of the five wetlands were dominated by their soil carbon pools (88.5–94.5%), and the vegetation carbon pool was secondary (5.5–11.5%). At the same time, their ecosystem net carbon balances were positive (0.1–0.6 t ha^(−1) a^(−1)) because the annual net carbon sequestration of vegetation (4.0–4.5 t ha^(−1) a^(−1)) were higher than the annual carbon emissions of soil heterotrophic respiration (CO_(2) and CH_(4)) (3.8–4.4 t ha^(−1) a^(−1)) in four wetlands, (the alder swamp being the exception), so all four were carbon sinks while only the alder swamp was a source of carbon emissions (− 2.1 t ha^(−1) a^(−1)) due to a degraded tree layer. Our results demonstrate that these forested wetlands were generally carbon sinks in the Xiaoxing’anling, and there was obvious spatial variation in carbon storage of ecosystems along the moisture gradient. 展开更多
关键词 Temperate forested wetlands Ecosystem carbon storage Carbon sink or source Xiaoxing’anling of China
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Nitrogen sink in a small forested watershed of subtropical China 被引量:4
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作者 Laiming Huang Jinling Yang Ganlin Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2011年第3期468-475,共8页
Global nitrogen(N)emission and deposition have been increased rapidly due to massive mobilization of N which may have long-reaching impacts on ecosystems.Many agricultural and forest ecosystems have been identified as... Global nitrogen(N)emission and deposition have been increased rapidly due to massive mobilization of N which may have long-reaching impacts on ecosystems.Many agricultural and forest ecosystems have been identified as secondary N sources.In the present study,the input-output budget of inorganic N in a small forested watershed of subtropical China was investigated.Inorganic N wet deposition and discharge by stream water were monitored from March,2007 to February,2009.The concentrations and fluxes of inorganic N in wet precipitation and stream water and net retention of N were calculated.Global N input by dry deposition and biological fixation and N output by denitrification for forested watersheds elsewhere were reported as references to evaluate whether the studied forested watershed is a source or a sink for N.The results show that the inorganic N output by the stream water is mainly caused by NO3-N even though the input is dominated by NH4+-N.The mean flux of inorganic N input by wet precipitation and output by stream water is 1.672 and 0.537 g N/(m2.yr),respectively,which indicates that most of inorganic N input is retained in the forested watershed.Net retention of inorganic N reaches 1.135 g N/(m2.yr)considering wet precipitation as the main input and stream water as the main output,ff N input by dry deposition and biological fixation and output by denitlification are taken into account,this subtropical forested watershed currently acts as a considerable sink for N,with a net sink ranging from 1.309 to 1.913 g N/(m2-yr)which may enhance carbon sequestration of the terrestrial ecosystem. 展开更多
关键词 forested watershed nitrogen deposition nitrogen sink subtropical China
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Hydrological functioning of forested catchments,Central Himalayan Region,India
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作者 Nuzhat Qazi 《Forest Ecosystems》 SCIE CSCD 2020年第4期833-850,共18页
Background:Central Himalayan forested catchments provide fresh water supply and innumerable ecosystem services to millions of people.Hence,the understanding of linkages between forests and water is very crucial for av... Background:Central Himalayan forested catchments provide fresh water supply and innumerable ecosystem services to millions of people.Hence,the understanding of linkages between forests and water is very crucial for availability and quality of water at catchment scale.Therefore,the present study aims to understand the hydrological response of two forested catchments(namely,Arnigad and Bansigad)in the Central Himalayan Region.Methods:Threeyears’data(March,2008 to February,2011)were collected from meteorological and hydrological stations in Arnigad and Bansigad catchments.The present paper describes the mean hydrological response of these forested catchments investigated through detailed field investigation.Results:The annual hyetograph analysis revealed that the rainfall at both the catchments was highly seasonal,and wetperiod(June–September)plays a key role in catchment functioning.Exceedance of rainfall threshold of^200 mm(~10%of annual rainfall)significantly increased streamflow generation in both catchments.In Arnigad,the stream was perennial with a mean baseflow of^83mm per month(~6%of annual baseflow)whereas,Bansigad had greater seasonality due to lack of streamflow during the prewetperiod(March–May).Separation of hydrographs in Arnigad and Bansigad catchments i.e.stormflow(6%and 31%,respectively)and baseflow(50%and 32%,respectively)helped to understand the probability of flooding during wetperiod and drought during dryperiod.The forest ecosystem in Arnigad displayed healthier hydrological functioning in terms of reduced stormflow(82%),and enhanced baseflow(52%),soil moisture(13%),steady infiltration rate(22%)and lag time(~15 min)relative to Bansigad.These enhanced values indicated soil capability to store water in the forested catchment(Arnigad)and helped to understand the volume of water(discharge)that was available during dryperiod.The lower denudation rate at Arnigad by 41%resulted in decreased suspended sediment(18%)and bed load(75%)compared to Bansigad.Further,the enhanced dissolved solids in the Arnigad stream resulted from the higher organic matter generated in the forest floor.Conclusion:This study shows that rainfall during the wetperiod was the main driver of hydrological functioning,whereas,forests provided substantial services by regulating water balance,soil moisture and sediment budget through different mechanisms of forest components at catchmentscale in the Central Himalayan Region. 展开更多
关键词 forested catchments STORMFLOW BASEFLOW Soil moisture Sediment transport Water budget
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Paludification reduces black spruce growth rate but does not alter tree water use efficiency in Canadian boreal forested peatlands
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作者 Joannie Beaulne Étienne Boucher +1 位作者 Michelle Garneau Gabriel Magnan 《Forest Ecosystems》 SCIE CSCD 2021年第2期373-386,共14页
Background:Black spruce(Picea mariana(Mill.)BSP)-forested peatlands are widespread ecosystems in boreal North America in which peat accumulation,known as the paludification process,has been shown to induce forest grow... Background:Black spruce(Picea mariana(Mill.)BSP)-forested peatlands are widespread ecosystems in boreal North America in which peat accumulation,known as the paludification process,has been shown to induce forest growth decline.The continuously evolving environmental conditions(e.g.,water table rise,increasing peat thickness)in paludified forests may require tree growth mechanism adjustments over time.In this study,we investigate tree ecophysiological mechanisms along a paludification gradient in a boreal forested peatland of eastern Canada by combining peat-based and tree-ring analyses.Carbon and oxygen stable isotopes in tree rings are used to document changes in carbon assimilation rates,stomatal conductance,and water use efficiency.In addition,paleohydrological analyses are performed to evaluate the dynamical ecophysiological adjustments of black spruce trees to site-specific water table variations.Results:Increasing peat accumulation considerably impacts forest growth,but no significant differences in tree water use efficiency(iWUE)are found between the study sites.Tree-ring isotopic analysis indicates no iWUE decrease over the last 100 years,but rather an important increase at each site up to the 1980 s,before iWUE stabilized.Surprisingly,inferred basal area increments do not reflect such trends.Therefore,iWUE variations do not reflect tree ecophysiological adjustments required by changes in growing conditions.Local water table variations induce no changes in ecophysiological mechanisms,but a synchronous shift in iWUE is observed at all sites in the mid-1980 s.Conclusions:Our study shows that paludification induces black spruce growth decline without altering tree water use efficiency in boreal forested peatlands.These findings highlight that failing to account for paludification-related carbon use and allocation could result in the overestimation of aboveground biomass production in paludified sites.Further research on carbon allocation strategies is of utmost importance to understand the carbon sink capacity of these widespread ecosystems in the context of climate change,and to make appropriate forest management decisions in the boreal biome. 展开更多
关键词 Black spruce growth Boreal biome Carbon allocation Ecophysiological mechanisms forested peatland Paludification Stable isotope Water use efficiency
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Metabolic diversity and seasonal variation of soil microbial communities in natural forested wetlands
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作者 Di Wu Qi Chi +3 位作者 Xin Sui Mengmeng Zhang Hongbai Jia Guangyu Sun 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第6期2619-2631,共13页
This study explores the effects of vegetation and season on soil microorganisms and enzymatic activity of different wetlands in a temperate climate.Microbial carbon metabolism diversity was assessed using community-le... This study explores the effects of vegetation and season on soil microorganisms and enzymatic activity of different wetlands in a temperate climate.Microbial carbon metabolism diversity was assessed using community-level physiological profiles(CLPP)with 31 different carbon substrates.CLPP indicated that significant interactions occur during carbon substrate metabolism of the microorganisms.Furthermore,the different types of vegetation present in the wetland ecosystem combined with the seasonal effects to influence microbial carbon metabolism and enzymatic activity.The most significant differences occurred to carbohydrates,carboxylic acids,and amino acids.The Mantel test confirmed positive correlations between soil enzymatic activities and microbial carbon metabolism.Soil microorganisms in Betula ovalifolia and Carex schmidtii wetlands used carbon substrates more efficiently in summer than those in other forested wetlands during other periods.Enzymatic activities also showed a similar trend as microbial carbon metabolism.The results demonstrate that microbial carbon metabolism patterns can be used as biological indicators in wetland ecological alterations due to vegetation type or to seasonal factors. 展开更多
关键词 forested wetlands Community-level physiological profiles(CLPP) Carbon metabolism diversity Soil enzymatic activity SEASONALITY
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Comparative study of some soil properties in forested and deforested areas in Cox’s Bazar and Rangamati Districts, Bangladesh
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作者 M.A.Zaman K.T.Osman S.M.Sirajul Haque 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第3期319-322,397,共5页
The study dealt with the assessment of impact of deforestation on soil through a comparative analysis of soil physicochemical properties of natural forest and deforested areas. Soil samples from three depths (top, mi... The study dealt with the assessment of impact of deforestation on soil through a comparative analysis of soil physicochemical properties of natural forest and deforested areas. Soil samples from three depths (top, middle and bottom) under natural forest and nearby deforested areas were collected to investigate soil properties. Forest soils show no sig-nificant change in particle size distribution. Bulk density of forested soils shows the significant differences in top and middle layers. Soil pH in top and middle soil, organic matter in top soil and available phosphorus in middle soil of the forest site are found to be significantly higher than that of the deforested soils. Forest soils also have significantly higher level of exchangeable Ca2+, K+ in top and middle soil and Mg2+ at all depth than those of deforested site. Exchangeable Na+ and cation exchange capacity (CEC) are observed unchanged in both sites. The results suggest that change in soil properties was more obvious in surface and sub surface portions of both areas. The study shows that deterioration of physicochemical properties occurred due to deforestation. 展开更多
关键词 chemical characteristics deforested soil forest soil physical characteristics
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Mapping Deciduous Broad-leaved Forested Swamps Using ALOS/Palsar Data
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作者 BIAN Hongfeng YAN Tingting +2 位作者 ZHANG Zhengxiang HE Chunguang SHENG Lianxi 《Chinese Geographical Science》 SCIE CSCD 2016年第3期352-365,共14页
Accurate, updated information on the distribution of wetlands is essential for estimating net fluxes of greenhouse gases and for effectively protecting and managing wetlands. Because of their complex community structu... Accurate, updated information on the distribution of wetlands is essential for estimating net fluxes of greenhouse gases and for effectively protecting and managing wetlands. Because of their complex community structure and rich surface vegetation, deciduous broad-leaved forested swamps are considered to be one of the most difficult types of wetland to classify. In this research, with the support of remote sensing and geographic information system, multi-temporal radar images L-Palsar were used initially to extract the forest hydrological layer and phenology phase change layer as two variables through image analysis. Second, based on the environmental characteristics of forested swamps, three decision tree classifiers derived from the two variables were constructed to explore effective methods to identify deciduous broad-leaved forested swamps. Third, this study focused on analyzing the classification process between flat-forests, which are the most severely disturbed elements, and forested swamps. Finally, the application of the decision tree model will be discussed. The results showed that: 1) L-HH band(a L band with wavelength of 0–235 m in HH polarization mode; HH means Synthetic Aperture Radars transmit pulses in horizontal polarization and receive in horizontal polarization) in the leaf-off season is shown to be capable of detecting hydrologic conditions beneath the forest; 2) the accuracy of the classification(forested swamp and forest plat) was 81.5% based on hydrologic features, and 83.5% was achieved by combining hydrologic features and phenology response features, which indicated that hydrological characteristics under the forest played a key role. The HHOJ(refers to the band created by the subtraction with HH band in October and HH band in July) achieved by multi-temporal radar images did improve the classification accuracy, but not significantly, and more leaf-off radar images may be more efficient than multi-seasonal radar images for inland forested swamp mapping; 3) the lower separability between forested swamps dominated by vegetated surfaces and forest plat covered with litter was the main cause of the uncertainty in classification, which led to misleading interpretations of the pixel-based classification. Finally, through the analysis with kappa coefficients, it was shown that the value of the intersection point was an ideal choice for the variable. 展开更多
关键词 forested swamp Palsar radar images forest hydrological characteristics multi-temporal technique decision tree classifier
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Sediment-Loading Processes in a Forested Catchment: Modeling and Observations
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作者 Md. Motaleb Hossain Kazuhisa A. Chikita Yoshitaka Sakata 《Open Journal of Modern Hydrology》 CAS 2023年第2期94-113,共20页
In order to investigate sediment-loading processes in a catchment, the daily time series of river discharge and sediment load were applied to a semi-distributed model, the Soil and Water Assessment Tool (SWAT). The ti... In order to investigate sediment-loading processes in a catchment, the daily time series of river discharge and sediment load were applied to a semi-distributed model, the Soil and Water Assessment Tool (SWAT). The time series of discharge and sediment load were obtained by monitoring the river stage and water turbidity of the Oikamanai River, Hokkaido, Japan, in the rainfall season (April-November) of 2011-2014. The catchment is forested (ca 90% area) but underlain by the Neogene sedimentary rocks with currently active faults and forest soils with tephra layers, which tend to frequently produce slope failure such as landslide and bank collapse by rainfall or snowmelt. The water turbidity, T, in ppm was converted into suspended sediment concentration, SSC, in g/L by applying the linear relationship between T and SSC. The acquisition of the time series of discharge, Q (m<sup>3</sup>/s) and sediment load, L (=Q·SSC in g/s) of the river allowed us to distinguish the fluvial sediment transport, accompanied by slope failure in the upstream, from that under no slope failure. The SWAT was used to simulate soil erosion and identify the region prone to the soil erosion in the Oikamanai River basin. The model’s results showed a satisfactory agreement between daily observed and simulated sediment load as indicated by the high Nash-Sutcliffe efficiency. This evidences that the upper mountainous region of the catchment provides a main sediment source, accompanied by slope failure. 展开更多
关键词 SWAT Slope Failure LANDSLIDE Bank Collapse forested Catchment Sediment Load
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Environmental influence in the forested area toward human health: incorporating the ecological environment into art psychotherapy 被引量:2
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作者 Ju-hyoung LEE Ji-sook PARK Sunnam CHOI 《Journal of Mountain Science》 SCIE CSCD 2020年第4期992-1000,共9页
This study on the development of a psychotherapy program based on the relationship between forests and human health focused on actively considering the natural ecological environment. This study categorized and compar... This study on the development of a psychotherapy program based on the relationship between forests and human health focused on actively considering the natural ecological environment. This study categorized and compared an art psychotherapy program that simply moved to an outdoor space and a forest-art therapy program that actively utilized the forest environment as a medium. The characteristics of the natural environment, such as openness, change, and diversity, shortened the amount of time participants took to develop a rapport and open up and played a vital role in recovering mental health. After a bold attempt at integrating forest environment and art psychotherapy by going beyond outdoor art therapy, there were significant results pertaining to improvements in mental disorders in today’s society, including stress vulnerabilities, depression, anxiety, and aggression. The research results verified that the developed forest-art therapy method had greater efficacy in relation to both the Stress Vulnerability-Interpersonal Sensitivity Scale and the Stress Vulnerability-Self-Regulation Scale. 展开更多
关键词 FOREST THERAPY Human health HEALING FOREST ART THERAPY FOREST environment
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Mushroom Production as an Alternative for Rural Development in a Forested Mountainous Area 被引量:1
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作者 José A.BONET José R.GONZáLEZ-OLABARRIA Juan MARTíNEZ DE ARAGóN 《Journal of Mountain Science》 SCIE CSCD 2014年第2期535-543,共9页
Wild mushrooms are recognized as important non-wood forest products in mountainous ecosystems, but their real potential for generating rural economies has not been fully evaluated due to the difficulties in obtaining ... Wild mushrooms are recognized as important non-wood forest products in mountainous ecosystems, but their real potential for generating rural economies has not been fully evaluated due to the difficulties in obtaining reliable productivity data, minimizing their true potential as contributor to rural economies. Mushroom yield models based on large data series from Pinus forest ecosystems in the region of Catalonia(Spain), combined with data from the Spanish National Forest Inventory allow us to estimate the potential mushroom productivity by forest ecosystems. The results of 24,500 tons/yr of mushrooms of which 16,300 tons are classified as edible and 7,900 tons are commonly marketed demonstrate the importance of mushroom productions in Catalonian pine forests, mostly located in mountainous areas where the development of agricultural activities is limited. Economic mushroom value is estimated at 48 million € for the edible mushroom and 32 million € for those corresponding to marketable yields, confirming the potential of this non-wood forest product. These production results and corresponding economic values provide a basis for the incorporation of wild mushrooms as significant non-wood forest products in the development of forest policies in mountainous areas. 展开更多
关键词 Non-wood forest products Mushroom models National Forest Inventory Economic value Mushroom potential estimation
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Measuring the Accuracy and Precision of the Garmin GPS Positioning in Forested Areas: A Case Study in Taxiarchis-Vrastama University Forest 被引量:2
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作者 Vasileios C. Drosos Chrisvaladis Malesios 《Journal of Environmental Science and Engineering(B)》 2012年第4期566-576,共11页
In this paper, it is attempted to examine and compare different orientation, one recreational and another more precise, in the performance of two (global positioning system) receivers of forested areas. In doing thi... In this paper, it is attempted to examine and compare different orientation, one recreational and another more precise, in the performance of two (global positioning system) receivers of forested areas. In doing this, a field test on horizontal and vertical positional errors of GPS positioning at different points in the forested area of Taxiarchis-Vrastama University forest was conducted. The two GPS receivers were used to determine the positional accuracy of a selected number of points under tree canopies. Specifically, the precision and accuracy of Garmin's GPS positioning at different points were calculated and compared with the corresponding positioning and accuracy of another GPS system, namely the TOPCON GPS. By the calculation of various measures of accuracy and precision suitable for GPS receivers and the use of statistical methods, accuracy between the different receivers differed significantly is shown. Also, regression analysis revealed that the basal area and the number of available satellites are the most important factors for predicting position error. 展开更多
关键词 ACCURACY GPS PRECISION positioning under forest canopy.
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Test of newly developed conceptual hydrological model for simulation of rain-on-snow events in forested watershed 被引量:1
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作者 Si-min QU Han LIU +3 位作者 Yan-ping CUI Peng SHI Wei-min BAO Zhong-bo YU 《Water Science and Engineering》 EI CAS CSCD 2013年第1期31-43,共13页
A conceptual hydrological model that links the Xin'anjiang hydrological model and a physically based snow energy and mass balance model, described as the XINSNOBAL model, was developed in this study for simulating ra... A conceptual hydrological model that links the Xin'anjiang hydrological model and a physically based snow energy and mass balance model, described as the XINSNOBAL model, was developed in this study for simulating rain-on-snow events that commonly occur in the Pacific Northwest of the United States. The resultant model was applied to the Lookout Creek Watershed in the H. J. Andrews Experimental Forest in the western Cascade Mountains of Oregon, and its ability to simulate streamflow was evaluated. The simulation was conducted at 24-hour and one-hour time scales for the period of 1996 to 2005. The results indicated that runoffand peak discharge could be underestimated if snowpack accumulation and snowmelt under rain-on-snow conditions were not taken into account. The average deterministic coefficient of the hourly model in streamflow simulation in the calibration stage was 0.837, which was significantly improved over the value of 0.762 when the Xin'anjiang model was used alone. Good simulation performance of the XINSNOBAL model in the WS 10 catchment, using the calibrated parameter of the Lookout Creek Watershed for proxy-basin testing, demonstrates that transplanting model parameters between similar watersheds can orovide a useful tool for discharge forecastin~, in un^au^ed basins. 展开更多
关键词 Xin 'anjiang model snow energy and mass balance model rain-on-snow event H. J.Andrews Experimental Forest
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A seed rain community in a reforested post-agricultural field and adjacent secondary forest of Mount Papandayan Nature Reserve,West Java,Indonesia
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作者 Nuri Nurlaila Setiawan Endah Sulistyawati 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第3期1013-1023,共11页
Understanding the mechanisms and barriers to the restoration of degraded land,especially post agriculture,will help provide protocols on effective ways of restoration into functional ecosystems.One of the barriers in ... Understanding the mechanisms and barriers to the restoration of degraded land,especially post agriculture,will help provide protocols on effective ways of restoration into functional ecosystems.One of the barriers in early stages of forest restoration is the arrival and availability of propagules.Seed rain and factors affecting it(i.e.,distance to the forest edge,species diversity and surrounding vegetation)were measured in a reforested post-agricultural field and in an adjacent secondary forest.Multivariate g lm analysis was used on the seed rain community data and univariate lm analysis on the most abundant seed captured(i.e.,Schima wallichii(DC.)Korth.).After 8 months of seed rain collection,there was a total of 3596 seeds from eight tree species.Seeds were more abundant and more diverse in the secondary forest(74.9%,8 species)compared to the reforested field(24.1%,2 species).There was a limitation on seed dispersal in reforested field from the adjacent forest.The abundance of S.wallichii seeds determined by the dominance of adult trees(136 trees/ha in the forest and 115 trees/ha in the reforested field).Our study suggests,that after 7 years of planting,the reforested field has received limited seed rain and has not yet recovered. 展开更多
关键词 Seed rain Montane tropical forest Post-agriculture succession Forest edge Multivariate analysis
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Forested Farmlands:Forest Management by Agroforestry Symbiosis in A Land Management Framework in South and South East Asia
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作者 Syed Ajijur Rahman Yulia Rahma Fitriana Kilian Walz 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期109-109,共1页
Forests provide multiple benefits as a safety net to the poor and also help to increase the overall ecological balance.Of particular importance in this respect this research has been conducted in six typical villages ... Forests provide multiple benefits as a safety net to the poor and also help to increase the overall ecological balance.Of particular importance in this respect this research has been conducted in six typical villages in South and Southeast Asia,located in Northern Bangladesh,Southern Myanmar and Northwest Thailand.Data collection methods were used by means of observation,FGD,interviews,and a structured survey of farm households.Data were analyzed through qualitative methods 展开更多
关键词 Swidden AGROFORESTRY FARMERS FOREST management
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Short-term effects of fire disturbance on CH4 emission from forested wetlands in the Xiaoxing’an Mountains, Northeast China
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作者 Han Gu Wenyu Zheng +1 位作者 Dawei Xu Changcheng Mu 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第3期969-979,共11页
Using static chamber gas chromatography, we determined the seasonal dynamics, controlling factors, and distribution patterns of forest swamp CH4 levels and related environmental factors (temperature, water level) afte... Using static chamber gas chromatography, we determined the seasonal dynamics, controlling factors, and distribution patterns of forest swamp CH4 levels and related environmental factors (temperature, water level) after fire disturbance in the Xiaoxing’an Mountains. The results showed the following: during the growing season, the annual CH4 emission distribution ranged from - 0.001 ± 0.012 to 22.373 ± 3.650 mg m^-2 h^-1;mild fire caused the swamp CH4 emission flux of tussock, shrub, Alnus sibirica and birch swamp to increase by 56.0–524.7%;at low water levels, temperature had a significant influence on the swamp type, and the correlation between the methane emission flux and temperature was significantly strengthened;after a fire disturbance, methane emissions from all types of marsh were highest in summer and second highest in autumn, with a weak absorption in spring;and along the water environment gradient of the transition zone, the CH4 emission flux presented a decreasing trend in its spatial distribution pattern. 展开更多
关键词 Xiaoxing’an MOUNTAINS FOREST SWAMP CH4 emission Fire DISTURBANCE
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Dissolved organic sulfur in streams draining forested catchments in southern China
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作者 Zhanyi Wang Xiaoshan Zhang +3 位作者 Zhangwei Wang Yi Zhang Bingwen Li Rolf Vogt 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第4期704-710,共7页
Dissolved organic sulfur (DOS) is an important fraction for sulfur mobilization in ecosystem. In this work stream waters were sampled in 25 forested sites in southern China to study the dissolved sulfur fractions. D... Dissolved organic sulfur (DOS) is an important fraction for sulfur mobilization in ecosystem. In this work stream waters were sampled in 25 forested sites in southern China to study the dissolved sulfur fractions. Dissolved sulfur was fractionated into dissolved organic sulfur (DOS) and inorganic sulfate (SO]-) for 95 stream water samples. The results showed that the concentration of DOS ranged from 0 to 13.1 mg/L (average 1,3 mg/L) in all the streams, High concentrations of DOS in stream waters were found in the sites with high concentrations of sulfate. DOS constituted less than 60.1% of dissolved sulfur (average 17.9%). Statistical analysis showed that DOS concentration was correlated with SO42- in streams waters and total sulfur in surface layer soils. The results also showed that DOS concentration in stream waters had a seasonal variation, but no trends were found with it. The implication was that the long term sulfur deposition had led the increase of the concentration and fraction of DOS in stream waters in acid rain prevailing regions 展开更多
关键词 dissolved organic sulfur stream water Chinese forests sulfur deposition
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Soil quality index as a tool for Scots pine(Pinus sylvestris) monoculture conversion planning on afforested,reclaimed mine land
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作者 Marcin Pietrzykowski 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第1期63-74,共12页
In Central Europe, a large portion of post-mining sites were afforested with Scots pine, which is characterized by good adaptability and a tolerance for poor habitat at the beginning of forest ecosystem development. C... In Central Europe, a large portion of post-mining sites were afforested with Scots pine, which is characterized by good adaptability and a tolerance for poor habitat at the beginning of forest ecosystem development. Conversion of monoculture on mine sites into more biodi- verse mixed hardwood forests, especially on more fertile deposits, can be an emerging need in this part of Europe in next decades. The ability to classify the forests at these post-mining sites will facilitate proper species selection as well as the management and formation of the developed ecosystem's stability. This work describes the guidelines that can be followed to assess reclaimed mine soil (RMS) quality, using the mine soil quality index (MSQI) and a classification of developed forest sites as a basis of tree-stand species selection and conversion of pine monocul- tures. The research was conducted on four post-mining facilities (lignite, hard coal, sulphur, and sand pit mining areas) on different RMS sub- strates dominant in Central Europe. Soil quality assessment takes into account the following features of the soil: texture soil nutrients (Ca, Mg, K, Na, P); acidity (pH KC1); and Corg-to-Nt ratio in the initial organic horizon. An analysis was conducted of classification systems using the MSQI validation correlation (at p =0.05) with vegetation features af- fected by succession: aboveground biomass of forest floor and ecological indicators of vascular plants (calculated on the basis of EUenberg's (2009) system). Eventually, in the analysed data set, the MSQI ranged from 0.270 for soils on quaternary sands to 0.720 for a mix of quaternary loamy sands with neogene clays. Potential forest habitat types and the role of the pine in the next generation of tree stands on different RMS parent rock substrate were proposed. 展开更多
关键词 mining sites AFFORESTATION pine monoculture conversion soil quality index forest habitat classification.
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Wild bee distribution near forested landscapes is dependent on successional state
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作者 Katherine A.Odanaka Sandra M.Rehan 《Forest Ecosystems》 SCIE CSCD 2020年第2期159-171,共13页
Background:Forested landscapes are valuable sources of ecosystem services especially in areas dedicated to intense agricultural activities.Distance from forest margin is known to influence the wild bee community in th... Background:Forested landscapes are valuable sources of ecosystem services especially in areas dedicated to intense agricultural activities.Distance from forest margin is known to influence the wild bee community in the landscape surrounding forested patches.Yet little is known regarding how bee communities distribute themselves in landscapes that exhibit different forest successional states.Methods:We examined how land use type and distance from the forest edge affect the abundance and richness of the wild bee community across four forest successional states.Bees were collected in sites representing four stages of forest succession and analyzed using generalized linear mixed models with negative binomial distributions.Results:Wild bee diversity is reduced in forested environments that maintain dense stands of trees and high canopy cover.Additionally,distance from the forest edge was an important factor determining wild bee distribution in successional stages adjacent to forest edges.Furthermore,we found that bees maintain high specificity for distinct successional states and distances.Conclusions:Our results demonstrate how different successional stages can harbor different bee species and highlight the ability of microhabitats to act as reservoirs of bee diversity in and around forest margins.Furthermore,we found that maximizing successional patchiness across forested landscapes increases the amount of available habitat that can support a diverse suite of bees with different nesting biologies and behaviors. 展开更多
关键词 POLLINATOR Forest margin Bee habitat Nesting biology Wild bees
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