Plant species diversity is one of the most widely used indicators in ecosystem management.The relation of species diversity with the size of the sample plot has not been fully determined for Oriental beech forests(Fag...Plant species diversity is one of the most widely used indicators in ecosystem management.The relation of species diversity with the size of the sample plot has not been fully determined for Oriental beech forests(Fagus orientalis Lipsky),a widespread species in the Hyrcanian region.Assessing the impacts of plot size on species diversity is fundamental for an ecosystem-based approach to forest management.This study determined the relation of species diversity and plot size by investigating species richness and abundance of both canopy and forest floor.Two hundred and fifty-six sample plots of 625 m^(2) each were layout in a grid pattern across 16 ha.Base plots(25 m×25 m)were integrated in different scales to investigate the effect of plot size on species diversity.The total included nine plots of 0.063,0.125,0.188,0.250,0.375,0.500,0.563,0.750 and 1 ha.Ten biodiversity indices were calculated.The results show that species richness in the different plot sizes was less than the actual value.The estimated value of the Simpson species diversity index was not significantly different from actual values for both canopy and forest floor diversity.The coefficient of variation of this index for the 1-ha sample plot showed the lowest amount across different plot sizes.Inverse Hill species diversity was insignificant difference across different plot sizes with an area greater than 0.500 ha.The modified Hill evenness index for the 1-ha sample size was a correct estimation of the 16-ha for both canopy and forest floor;however,the precision estimation was higher for the canopy layer.All plots greater than 0.250-ha provided an accurate estimation of the Camargo evenness index for forest floor species,but was inaccurate across different plot sizes for the canopy layer.The results indicate that the same plot size did not have the same effect across species diversity measurements.Our results show that correct estimation of species diversity measurements is related to the selection of appropriate indicators and plot size to increase the accuracy of the estimate so that the cost and time of biodiversity management may be reduced.展开更多
Understanding local variation in forest biomass allows for a better evaluation of broad-scale patterns and interpretation of forest ecosystems’role in carbon dynamics.This study focuses on patterns of aboveground tre...Understanding local variation in forest biomass allows for a better evaluation of broad-scale patterns and interpretation of forest ecosystems’role in carbon dynamics.This study focuses on patterns of aboveground tree biomass within a fully censused 20 ha forest plot in a temperate forest of northern Alabama,USA.We evaluated the relationship between biomass and topography using ridge and valley landforms along with digitally derived moisture and solar radiation indices.Every live woody stem over 1 cm diameter at breast height within this plot was mapped,measured,and identified to species in 2019-2022,and diameter data were used along with speciesspecific wood density to map the aboveground biomass at the scale of 20 m×20 m quadrats.The aboveground tree biomass was 211 Mg·ha^(-1).Other than small stream areas that experienced recent natural disturbances,the total stand biomass was not associated with landform or topographic indices.Dominant species,in contrast,had strong associations with topography.American beech(Fagus grandifolia)and yellow-poplar(Liriodendron tulipfera)dominated the valley landform,with 37% and 54% greater biomass in the valley than their plot average,respectively.Three other dominant species,white oak(Quercus alba),southern shagbark hickory(Carya carolinaeseptentrionalis),and white ash(Fraxinus americana),were more abundant on slopes and benches,thus partitioning the site.Of the six dominant species,only sugar maple(Acer saccharum)was not associated with landform.Moreover,both topographic wetness and potential radiation indices were significant predictors of dominant species biomass within each of the landforms.The study highlights the need to consider species when examining forest productivity in a range of site conditions.展开更多
Five years＇ （2000-2004） continuous study has been carried out on small mammals such as rodents in seven different sample plots, at three different altitudes and in six different ecological environment types in the ...Five years＇ （2000-2004） continuous study has been carried out on small mammals such as rodents in seven different sample plots, at three different altitudes and in six different ecological environment types in the eastern part of the Wuling Mountains, south bank of the Three Gorges of Yangtze River in Hubei. A total of 29 297 rat clamps/times were placed and 2271 small mammals such as rodents were captured, and 26 small mammals were captured by other means. All the small mammals captured belonged to 8 families 19 genera and 24 species, of which rodentia accounted for 70.83% and insectivora 29.17%. Through analysis of the data, the results showed that： 1 ） although the species richness had a trend of increasing along different sample plots as altitude increased from south to north, quite a few species showed a wide habitat range in a vertical distribution （ 15 species were dispersed over three zones and two species over two zones） , indicating a strong adaptability of small mammals such as rOdents at lower altitudes in most areas and comparatively less vertical span of entire mountains; 2） whether in seven different sample plots or six different ecological types, Apodemus agrarius and Rattus norvegicus were dominant species below 1200m, and Anourosorex squamipes, Niviventer confucianus and Apodemus draco were dominant above altitudes of 1300m, however, in quantity they were short of identical regularity, meaning they did not increase as the altitude did, or decrease as the ecological areas changed; 3）the density in winter was obviously greater than that in spring, and the distribution showed an increasing trend along with altitude, but the density in different sample plots was short of identical regularity, showing changes in different seasons and altitude grades had an important impact on small mammals such as rodents; 4） in species diversity and evenness index, there were obvious changes between the seven different sample plots, probably caused by frequent human interference in this area. Comparatively speaking, there was less human interference at high altitudes where vegetation was rich and had a high diversity and evenness index, and the boundary effect and community stability were obvious. Most ecological types have been seriously interfered with due to excessive assart at low altitudes with singular vegetation and low diversity and evenness index and poor community stability, showing an ecosystem with poor anti-reversion. If human interference can be reduced in those communities at high altitudes with low diversity and evenness index, the biological diversity in the communities will gradually recover to similar levels of other ecological areas.展开更多
[Objective] The aim was to study on impacts of excessive soaking N, P, and K insubstrate plots of and seedling growth. [Method] Substrate was designed to add additional 1/2 water after saturation and expansion. Dispos...[Objective] The aim was to study on impacts of excessive soaking N, P, and K insubstrate plots of and seedling growth. [Method] Substrate was designed to add additional 1/2 water after saturation and expansion. Disposable excessive soak- ing and regression relation of nutrition infusion of substrate plots were studied by design of 13 time gradient. Plant nutrition absorption and growth effects after sub- strate plots immersed by water were investigated by growing tomato. [Result] Con- centration and time of the three nutrition immersed in water had the regression equation of each, as follows： N=-2E-05t2＋0.016 lt＋2.0553, P=0.002 2t＋2.248 5 and K=0.004 7t＋0.875 8. With nutrition loss of the three, however, loss amount was al- most same with variance analysis of regression equation, which may result from its volatilization. Regression equations of P and K were： P=0.125 7t-0.117, and K=0.022 5t.1514, which led to adverse impact on plant absorption of N and K above ground, whose equations were N=20.64e-4E-0.4t, and K=E-06t2-0.011 3t＋29.055. Meanwhile, un- der the condition, sound seedling index was not impacted a lot by excessive immer- sion. [Conclusion] This study has provided theoretical reference for guidance of sub- strate plot soaking method, cultivation and regulation, and breeding, as well as agri- cultural production.展开更多
The Mesoproterozoic Wumishan Formation ((1310 ± 20 ) Ma - (l 207 ± 10) Ma) in Jixian, Tianjin represents a succession of 3 300 meter thick carbonate strata where are the best developed stromatolite biostrom...The Mesoproterozoic Wumishan Formation ((1310 ± 20 ) Ma - (l 207 ± 10) Ma) in Jixian, Tianjin represents a succession of 3 300 meter thick carbonate strata where are the best developed stromatolite biostromes and thrombolite bioherms. These biostromes and bioherms, together with tidal-flat dolomites and muddy dolostones, form Wumishan cyclothems with approximately symmetrical faciessuccession fabrics, which belong to carbonate meter-scale cyclic sequences of peritidal type. These cyclothems are overlain by lagoon dolomitic mudstones and shales and by frequently developed paleosol layers, indicating that the boundary of Wumishan cyclothems is marked by an instantaneously-exposed punctuated surface. Viewed form the regularly vertical stacking patterns of Wumishan cyclothems in long-term sequences, 26 third-order sequences may be discerned in Wumishan Formation. These thirdorder sequences may also be incorporated into six second-order sequences. In order to study the variation range of third-order sea-level changes and the formation period of third-order sequence, 626 cyclothems are discerned in the middle and upper parts of Wumishan Formation where the outcrops are well developed. In terms of the total thickness and the formation period of Mesoproterozoic Wumishan Formation, the crust subsidence rate in the sedimentary period of Wumishan Formation is supposed to be 3 meters at each interval of 100 thousands years. Based on this assumption, Fischer plot might be designed to simulate the third-order sea-level changing pattern.展开更多
Lorenz-RR scatter plot has an obvious shortcoming in that it does not indicate the time when the scatter point happens.On the Lorenz RR scatter plot,one cannot know the time during which the cardiac rhythms take place...Lorenz-RR scatter plot has an obvious shortcoming in that it does not indicate the time when the scatter point happens.On the Lorenz RR scatter plot,one cannot know the time during which the cardiac rhythms take place.Since occurrence of cardiac rhythms is time-related,time should be introduced to such plots.In this study,time was used as abscissa and RR interval(the time interval between the previous RR wave and the R wave)as the ordinate and time was compressed into a visually observable length,and thereby a timed RR-interval scatter plot,or t-RR scatter plot,for short,was developed.On t-RR scatter plot,the patterns were band-shaped or were of linear type.On the t-RR plot,the sinus rhythm presented bands of various widths,with the spiculate or burred upper and lower boundaries,having diurnal variation.Premature beats showed separate layers(“stratification”),the layer number corresponding the number of RR-intervals.With simple premature beats,the layers were clearly separated.With parasystole rhythm,the upper and lower bands or layers might become thicker.With arial premature beats,the space or distance between layers varied.Ventricular premature beats presented equal space or distance between layers.With tachycardia,the lower layer became a“solid”layer.With atrial fibration,the“stratification”disappeared,presenting thicker or widened layers or bands,with neat lower boundary.With atrial flutter,the layers went parallel,with the layers being evenly separated or some distances being exact multiples of others.The second degree atrioventricular block displayed two layers,the lower and upper bands being equally away from the X-axis,presenting a straight line(pacing at a fixed rate)or a thicker or wider bands,with a neat upper boundary(the lowest pacing rate).When the scatter plot presented uncharacteristic patterns or had some scattered points,which rendered diagnosis difficult,a reverse technology could be used.Briefly,upon selection of scattered points,they were subjected to computerization,by regression,to reveal the piece of electrocardiogram(ECG)containing an R wave(QRS complex).Then ECG was analyzed to diagnose the cardiac rhythms.In conclusion,t-RR is a novel methodology which helps us understand heart rhythms from a new perspective.展开更多
Swidden agriculture is by far the dominant land use system in the uplands of Southeast Asia （SEA）, as well as other tropical regions, which plays an important role in the implementation of Reducing Emissions from De...Swidden agriculture is by far the dominant land use system in the uplands of Southeast Asia （SEA）, as well as other tropical regions, which plays an important role in the implementation of Reducing Emissions from Deforestation and Forest Degradation （REDD） of United Nations. To our knowledge, the long-term inter-annual area of newly burned plots （NBP） of swidden agriculture in mainland Southeast Asia is still not available, let alone in the whole tropics. With the strengthening regional geo-economic cooperation in SEA, swidden agriculture has experienced and/or is still experiencing extensive and drastic transformations into other diverse market-oriented land use types since the 1990s. In this study, high-level surface reflectance products of Landsat 4151718 family sensors including Thematic Mapper （TM）, Enhanced Thematic Mapper Plus （ETM＋） and Operational Land Imager （OLI） acquired in March, April and May of each year between 1988 and 2016 were firstly utilized to detect and monitor the extent and area of NBP of swidden agriculture with multiple thresholds of four commonly-used vegetation indices, namely the Normalized Difference Vegetation Index （NDVI）, Normalized Difference Moisture Index （NDMI）, Normalized Burn Ratio （NBR） and Soil Adjusted Vegetation Index （SAVI）, in combination with local phenological features of swid- dening and topographical data. The results showed that： （1） an annual average of 6.08×104 km2 of NBP of swidden agriculture, or 3.15% of the total land area of MSEA, were estimated in the past nearly three decades. （2） Annual NBP were primarily distributed in four major geomorphic units including the Central Range of Hills, Northern Mountainous Region, West- ern Myanmar Hills, and Annamite Chain. （3） A decadal average analysis indicated that the NBP of swidden agriculture opened year by year declined as a whole, especially after 2010, merely with an average of 5.23×104 km2. （4） The top ten provincial administrative units in Cambodia, Laos, Myanmar, Thailand and Vietnam, which consistently accounted for over 90% of the newly opened swiddens of each country, showed distinct fluctuations in usingslash-and-burn practices in the last decades. The Landsat-based （30 m） reconstructed 29-year longitudinal updated maps （including extent and area） of the NBP of swidden agri- culture may contribute to REDD and local livelihood related studies in Continental Southeast Asia. Our study further demonstrated that the multiple vegetative indices thresholds approach holds great potential in detecting swidden agriculture in tropical mountainous regions.展开更多
There are many techniques using sensors and wearable devices for detecting and monitoring patients with Parkinson’s disease(PD).A recent development is the utilization of human interaction with computer keyboards for...There are many techniques using sensors and wearable devices for detecting and monitoring patients with Parkinson’s disease(PD).A recent development is the utilization of human interaction with computer keyboards for analyzing and identifying motor signs in the early stages of the disease.Current designs for classification of time series of computer-key hold durations recorded from healthy control and PD subjects require the time series of length to be considerably long.With an attempt to avoid discomfort to participants in performing long physical tasks for data recording,this paper introduces the use of fuzzy recurrence plots of very short time series as input data for the machine training and classification with long short-term memory(LSTM)neural networks.Being an original approach that is able to both significantly increase the feature dimensions and provides the property of deterministic dynamical systems of very short time series for information processing carried out by an LSTM layer architecture,fuzzy recurrence plots provide promising results and outperform the direct input of the time series for the classification of healthy control and early PD subjects.展开更多
The arrangement of natural and physical features on the earth’s surface are a few among the countless items that govern the airborne acoustic transmission at boundary layers.In particular,if the acoustic waves are at...The arrangement of natural and physical features on the earth’s surface are a few among the countless items that govern the airborne acoustic transmission at boundary layers.In particular,if the acoustic waves are attributes of live concerts at open-air theatres,without losing the sheen and quality,the audience should certainly receive the unbroken depth of the performance.Hence,at all times,it is advisable to analyse the auditory receptiveness,particularly in all intended recreational spaces.The current pandemic circumstances and the mandated COVID-19 prevention protocols encourage gatherings in naturally ventilated outdoor regions than confined indoors.This work predicts and quantifies the acoustic experience at the naturally carved amphitheatre at SAINTGITS,an autonomous institution at the down South-West of the Indian Subcontinent.The entire recreational space at SAINTGITS AMPHI was separately modelled as a Base case and Advanced case,and were analysed using the acoustic modelling module of EASE Focus,a renowned simulation freeware,which is in strict adherence with the International standards.The variation in loudness received at the nearest and farthest ends of the amphitheatre was between 67 to 80 dB.Though the Zero frequency SPL(Z-weighting)exhibited the loudness in the range of 81 to 85 dB and could maintain a safer auditory level for any human ear,it was confined to a hemispherical region near the sound source.A vertical beam angle of−4.0°was found to be effective throughout.The procedures and analyses will certainly help the future organizers and stakeholders to effectively plan the resources to reap rich acoustic experience at terrain-centric locales.The surface topography and contours were plotted with another set of freeware,the CADMAPPER and the QUIKGRID,to compare terrain gradient with the known data.Furthermore,this interdisciplinary research exhibits the extensive simulation capability of both EASE Focus and QUIKGRID and demonstrates the modelling versatility and deliverable potential of these freeware to benefit the budding architects and researchers.展开更多
A series of related electrophysiology phenomena can be caused by the occurrence of interpolated ventricular premature contraction.In our recent three-dimensional Lorenz R-R scatter plot research,we found that atrioven...A series of related electrophysiology phenomena can be caused by the occurrence of interpolated ventricular premature contraction.In our recent three-dimensional Lorenz R-R scatter plot research,we found that atrioventricular node double path caused by interpolated ventricular premature contraction imprints a specifi c pattern on three-dimensional Lorenz plots generated from 24-hour Holter recordings.We found two independent subclusters separated from the interpolated premature beat precluster,the interpolated premature beat cluster,and the interpolated premature beat postcluster,respectively.Combined with use of the trajectory tracking function and the leap phenomenon,our results reveal the presence of the atrioventricular node double conduction path.展开更多
The parallel coordinate plot is proposed as an efficient tool for visualization of 13 traits of ＂stay-green＂ maize（Zea mays L.） cultivar exposed to different methods of magnesium application. The field experiment ...The parallel coordinate plot is proposed as an efficient tool for visualization of 13 traits of ＂stay-green＂ maize（Zea mays L.） cultivar exposed to different methods of magnesium application. The field experiment was conducted in the Department of Agronomy, Poznań University of Life Sciences, on the fields of the Department of Teaching and Experimental Station in Swadzim in 2006–2008. Experiment was conducted as a single-factor experiment with seven applications of magnesium in a randomized complete block design with four replicates. The highest mean values of grain yield and 1 000-grain weight were obtained after application of variant T3 of magnesium（10 kg MgO ha^–1 soil） in the all three years of study.展开更多
Data from vegetation succession study is usually a matrix of plot × species × time.It is difficult to analyse this kind of data at present.A simple technique,clustercentering ordination is described in this ...Data from vegetation succession study is usually a matrix of plot × species × time.It is difficult to analyse this kind of data at present.A simple technique,clustercentering ordination is described in this paper,which can be used to analyse such a matrix directly.The data of 5 permanent plots in 7 years of inlands and grasslands in Kootwijki,the Netherlands,is analysed using this method as an application example.The results obviously illustrate the trend,direction and speedof community succession and can be easily interbrated.This suggests that clustercentering ordination is an effective and time-saving technique in study of vegetation succession.展开更多
In order to study the dynamics of uneven-aged stands of interior Douglas-fir, Pseudotsuga menzesii var.glouca (Mirb.) Franco in future, six permanent sample plots wer set up on the Knife Creek Block of the Alex Fraser...In order to study the dynamics of uneven-aged stands of interior Douglas-fir, Pseudotsuga menzesii var.glouca (Mirb.) Franco in future, six permanent sample plots wer set up on the Knife Creek Block of the Alex Fraser Researh Forcst of University of British Columbia. The measurements and observations for all living trees within theboundaries of a plot wer madc, including DBH(diameter at breast height), TTH(total tree height), height to lowest livingbranch, crown diameter, tree vigor, angle of lean, distance of lean, direction of lean and tree location. Based on the data,some stand characteristics of the plots were analyzed simply and preliminarily. Results showed that most of the interiortrees on the plots are ranged 10-20 cm in distribution of DBH class, and 2-6 m in distribution of rm class. Trees withdifferent fors, however, are distributed unevenly. The relationship between total tree height and diameter at breast heightfollows a quadratic distribution, Y=a+bX+cX2.展开更多
Although many sensitivity analyses using the soil and water assessment tool(SWAT) in a complex watershed have been conducted, little attention has been paid to the application potential of the model in unique plots. I...Although many sensitivity analyses using the soil and water assessment tool(SWAT) in a complex watershed have been conducted, little attention has been paid to the application potential of the model in unique plots. In addition, sensitivity analysis of percolation and evapotranspiration with SWAT has seldom been undertaken. In this study, SWAT99.2 was calibrated to simulate water balance components for unique plots in Southern China from 2000 to 2001, which included surface runoff, percolation, and evapotranspiration. Twenty-one parameters classified into four categories, including meteorological conditions, topographical characteristics, soil properties, and vegetation attributes, were used for sensitivity analysis through one-at-a-time(OAT) sampling to identify the factor that contributed most to the variance in water balance components. The results were shown to be different for different plots, with parameter sensitivity indices and ranks varying for different water balance components. Water balance components in the broad-leaved forest and natural grass plots were most sensitive to meteorological conditions, less sensitive to vegetation attributes and soil properties, and least sensitive to topographical characteristics. Compared to those in the natural grass plot, water balance components in the broad-leaved forest plot demonstrated higher sensitivity to the maximum stomatal conductance(GSI) and maximum leaf area index(BLAI).展开更多
Aquifer test methods have greatly improved in recent years with the advent of inverse analysis, derivative analysis, and diagnostic plots. Updated analyses of past aquifer tests allow for improved interpretations of t...Aquifer test methods have greatly improved in recent years with the advent of inverse analysis, derivative analysis, and diagnostic plots. Updated analyses of past aquifer tests allow for improved interpretations of the data to enhance the knowledge and the predictive capabilities of the flow system. This work thoroughly reanalyzes a series of pre- and post-hydraulic fracturing, single-well aquifer tests conducted in two crystalline rock wells in New Hampshire as part of an early 1970’s study. Previous analyses of the data had relied on older manual type-curve methods for predicting the possible effects of hydraulic fracturing. This work applies inverse analysis, derivative analysis, and diagnostic plots to reanalyze the 1970’s aquifer test data. Our results demonstrate that the aquifer tests were affected by changes in flow regimes, dewatering of the aquifer and discrete fractures, and changes due to well development. Increases in transmissivities are related to well development prior to hydraulic fracturing, propagation of a single, vertical fracture hydraulically connecting the two wells after stimulation and expansion of troughs of depression. After hydraulic fracturing, the estimated total yield of the individual wells increased by 2.5 times due to the hydraulic fracturing. However, the wells may be receiving water from the same source, and well interference may affect any significant increase in their combined yield. Our analyses demonstrate the value in applying inverse analysis, derivative analysis, and diagnostic plots over the conventional method of manual type-curve analysis. In addition, our improvement in the aquifer test interpretation of the 1970’s test data has implications for more reliable estimates of sustained well yields.展开更多
The two-parameter lognormal distribution is a variant of the normal distribution and the three-parameter lognormal distribution is an extension of the two-parameter lognormal distribution by introducing a location par...The two-parameter lognormal distribution is a variant of the normal distribution and the three-parameter lognormal distribution is an extension of the two-parameter lognormal distribution by introducing a location parameter. The Q-Q plot of the three-parameter lognormal distribution is widely used. To obtain the Q-Q plot one needs to iteratively try different values of the shape parameter and subjectively judge the linearity of the Q-Q plot. In this paper,a mathematical method was proposed to determine the value of the shape parameter so as to simplify the generation of the Q-Q plot. Then a new probability plot was proposed,which was more easily obtained and provided more accurate parameter estimates than the Q-Q plot. These are illustrated by three realworld examples.展开更多
Given a sample of regression data from (Y, Z), a new diagnostic plotting method is proposed for checking the hypothesis H0: the data are from a given Cox model with the time-dependent covariates Z. It compares two est...Given a sample of regression data from (Y, Z), a new diagnostic plotting method is proposed for checking the hypothesis H0: the data are from a given Cox model with the time-dependent covariates Z. It compares two estimates of the marginal distribution FY of Y. One is an estimate of the modified expression of FY under H0, based on a consistent estimate of the parameter under H0, and based on the baseline distribution of the data. The other is the Kaplan-Meier-estimator of FY, together with its confidence band. The new plot, called the marginal distribution plot, can be viewed as a test for testing H0. The main advantage of the test over the existing residual tests is in the case that the data do not satisfy any Cox model or the Cox model is mis-specified. Then the new test is still valid, but not the residual tests and the residual tests often make type II error with a very large probability.展开更多
The use of Recurrence plots have been extensively used in various fields. In this work, Recurrence Plots (RPs) investigates the changes in the non-linear behaviour of urban air pollution using large datasets of raw da...The use of Recurrence plots have been extensively used in various fields. In this work, Recurrence Plots (RPs) investigates the changes in the non-linear behaviour of urban air pollution using large datasets of raw data (hourly). This analysis has not been used before to extract information from large datasets for this type non-linear problem. Two different approaches have been used to tackle this problem. The first approach is to show results according to monitoring network. The second approach is to show the results by particle type. This analysis shows the feasibility of using Recurrence Analysis for pollution monitoring and control.展开更多
基金funded by Gorgan University of Agricultural Sciences and Natural Resources(grant number 9318124503).
文摘Plant species diversity is one of the most widely used indicators in ecosystem management.The relation of species diversity with the size of the sample plot has not been fully determined for Oriental beech forests(Fagus orientalis Lipsky),a widespread species in the Hyrcanian region.Assessing the impacts of plot size on species diversity is fundamental for an ecosystem-based approach to forest management.This study determined the relation of species diversity and plot size by investigating species richness and abundance of both canopy and forest floor.Two hundred and fifty-six sample plots of 625 m^(2) each were layout in a grid pattern across 16 ha.Base plots(25 m×25 m)were integrated in different scales to investigate the effect of plot size on species diversity.The total included nine plots of 0.063,0.125,0.188,0.250,0.375,0.500,0.563,0.750 and 1 ha.Ten biodiversity indices were calculated.The results show that species richness in the different plot sizes was less than the actual value.The estimated value of the Simpson species diversity index was not significantly different from actual values for both canopy and forest floor diversity.The coefficient of variation of this index for the 1-ha sample plot showed the lowest amount across different plot sizes.Inverse Hill species diversity was insignificant difference across different plot sizes with an area greater than 0.500 ha.The modified Hill evenness index for the 1-ha sample size was a correct estimation of the 16-ha for both canopy and forest floor;however,the precision estimation was higher for the canopy layer.All plots greater than 0.250-ha provided an accurate estimation of the Camargo evenness index for forest floor species,but was inaccurate across different plot sizes for the canopy layer.The results indicate that the same plot size did not have the same effect across species diversity measurements.Our results show that correct estimation of species diversity measurements is related to the selection of appropriate indicators and plot size to increase the accuracy of the estimate so that the cost and time of biodiversity management may be reduced.
基金supported in part by the intramural research program of the US Department of Agriculture,National Institute of Food and Agriculture,Evans-Allen#1024525,and Capacity Building Grant#006531supported in part by the US National Science Foundation RII Track 2 FEC:Leveraging Intelligent Informatics and Smart Data for Improved Understanding of Northern Forest Ecosystem Resiliency(INSPIRES)#1920908by The Lyndhurst Foundation.
文摘Understanding local variation in forest biomass allows for a better evaluation of broad-scale patterns and interpretation of forest ecosystems’role in carbon dynamics.This study focuses on patterns of aboveground tree biomass within a fully censused 20 ha forest plot in a temperate forest of northern Alabama,USA.We evaluated the relationship between biomass and topography using ridge and valley landforms along with digitally derived moisture and solar radiation indices.Every live woody stem over 1 cm diameter at breast height within this plot was mapped,measured,and identified to species in 2019-2022,and diameter data were used along with speciesspecific wood density to map the aboveground biomass at the scale of 20 m×20 m quadrats.The aboveground tree biomass was 211 Mg·ha^(-1).Other than small stream areas that experienced recent natural disturbances,the total stand biomass was not associated with landform or topographic indices.Dominant species,in contrast,had strong associations with topography.American beech(Fagus grandifolia)and yellow-poplar(Liriodendron tulipfera)dominated the valley landform,with 37% and 54% greater biomass in the valley than their plot average,respectively.Three other dominant species,white oak(Quercus alba),southern shagbark hickory(Carya carolinaeseptentrionalis),and white ash(Fraxinus americana),were more abundant on slopes and benches,thus partitioning the site.Of the six dominant species,only sugar maple(Acer saccharum)was not associated with landform.Moreover,both topographic wetness and potential radiation indices were significant predictors of dominant species biomass within each of the landforms.The study highlights the need to consider species when examining forest productivity in a range of site conditions.
基金National Natural Science Foundation of China(30070679)the Natural Science Foundation of Hubei Province(2004ABA138)+1 种基金the Key Technology R&D Programme Foundation of Hubei Province(2002AA301C43)the Hubei Health Bureau Research Programme Foundation(NX200427)
文摘Five years＇ （2000-2004） continuous study has been carried out on small mammals such as rodents in seven different sample plots, at three different altitudes and in six different ecological environment types in the eastern part of the Wuling Mountains, south bank of the Three Gorges of Yangtze River in Hubei. A total of 29 297 rat clamps/times were placed and 2271 small mammals such as rodents were captured, and 26 small mammals were captured by other means. All the small mammals captured belonged to 8 families 19 genera and 24 species, of which rodentia accounted for 70.83% and insectivora 29.17%. Through analysis of the data, the results showed that： 1 ） although the species richness had a trend of increasing along different sample plots as altitude increased from south to north, quite a few species showed a wide habitat range in a vertical distribution （ 15 species were dispersed over three zones and two species over two zones） , indicating a strong adaptability of small mammals such as rOdents at lower altitudes in most areas and comparatively less vertical span of entire mountains; 2） whether in seven different sample plots or six different ecological types, Apodemus agrarius and Rattus norvegicus were dominant species below 1200m, and Anourosorex squamipes, Niviventer confucianus and Apodemus draco were dominant above altitudes of 1300m, however, in quantity they were short of identical regularity, meaning they did not increase as the altitude did, or decrease as the ecological areas changed; 3）the density in winter was obviously greater than that in spring, and the distribution showed an increasing trend along with altitude, but the density in different sample plots was short of identical regularity, showing changes in different seasons and altitude grades had an important impact on small mammals such as rodents; 4） in species diversity and evenness index, there were obvious changes between the seven different sample plots, probably caused by frequent human interference in this area. Comparatively speaking, there was less human interference at high altitudes where vegetation was rich and had a high diversity and evenness index, and the boundary effect and community stability were obvious. Most ecological types have been seriously interfered with due to excessive assart at low altitudes with singular vegetation and low diversity and evenness index and poor community stability, showing an ecosystem with poor anti-reversion. If human interference can be reduced in those communities at high altitudes with low diversity and evenness index, the biological diversity in the communities will gradually recover to similar levels of other ecological areas.
基金Supported by Action Programs of Service Business of Scientists and Engineers in MOST(2009GJA00026)Science and Technology Project of Beijing Municipal Bureau of Agriculture(2010020101)+1 种基金Science and Technology project of Beijing Municipal Bureau of Agriculture(011050465100002)Science and Technology Project of Beijing Academy of Agricultural and Forestry Sciences(2010A016)~~
文摘[Objective] The aim was to study on impacts of excessive soaking N, P, and K insubstrate plots of and seedling growth. [Method] Substrate was designed to add additional 1/2 water after saturation and expansion. Disposable excessive soak- ing and regression relation of nutrition infusion of substrate plots were studied by design of 13 time gradient. Plant nutrition absorption and growth effects after sub- strate plots immersed by water were investigated by growing tomato. [Result] Con- centration and time of the three nutrition immersed in water had the regression equation of each, as follows： N=-2E-05t2＋0.016 lt＋2.0553, P=0.002 2t＋2.248 5 and K=0.004 7t＋0.875 8. With nutrition loss of the three, however, loss amount was al- most same with variance analysis of regression equation, which may result from its volatilization. Regression equations of P and K were： P=0.125 7t-0.117, and K=0.022 5t.1514, which led to adverse impact on plant absorption of N and K above ground, whose equations were N=20.64e-4E-0.4t, and K=E-06t2-0.011 3t＋29.055. Meanwhile, un- der the condition, sound seedling index was not impacted a lot by excessive immer- sion. [Conclusion] This study has provided theoretical reference for guidance of sub- strate plot soaking method, cultivation and regulation, and breeding, as well as agri- cultural production.
基金the National Natural ScienceFoundation of China (No. 49802012) and also by the Ministry of Science and Technology (SSER).
文摘The Mesoproterozoic Wumishan Formation ((1310 ± 20 ) Ma - (l 207 ± 10) Ma) in Jixian, Tianjin represents a succession of 3 300 meter thick carbonate strata where are the best developed stromatolite biostromes and thrombolite bioherms. These biostromes and bioherms, together with tidal-flat dolomites and muddy dolostones, form Wumishan cyclothems with approximately symmetrical faciessuccession fabrics, which belong to carbonate meter-scale cyclic sequences of peritidal type. These cyclothems are overlain by lagoon dolomitic mudstones and shales and by frequently developed paleosol layers, indicating that the boundary of Wumishan cyclothems is marked by an instantaneously-exposed punctuated surface. Viewed form the regularly vertical stacking patterns of Wumishan cyclothems in long-term sequences, 26 third-order sequences may be discerned in Wumishan Formation. These thirdorder sequences may also be incorporated into six second-order sequences. In order to study the variation range of third-order sea-level changes and the formation period of third-order sequence, 626 cyclothems are discerned in the middle and upper parts of Wumishan Formation where the outcrops are well developed. In terms of the total thickness and the formation period of Mesoproterozoic Wumishan Formation, the crust subsidence rate in the sedimentary period of Wumishan Formation is supposed to be 3 meters at each interval of 100 thousands years. Based on this assumption, Fischer plot might be designed to simulate the third-order sea-level changing pattern.
文摘Lorenz-RR scatter plot has an obvious shortcoming in that it does not indicate the time when the scatter point happens.On the Lorenz RR scatter plot,one cannot know the time during which the cardiac rhythms take place.Since occurrence of cardiac rhythms is time-related,time should be introduced to such plots.In this study,time was used as abscissa and RR interval(the time interval between the previous RR wave and the R wave)as the ordinate and time was compressed into a visually observable length,and thereby a timed RR-interval scatter plot,or t-RR scatter plot,for short,was developed.On t-RR scatter plot,the patterns were band-shaped or were of linear type.On the t-RR plot,the sinus rhythm presented bands of various widths,with the spiculate or burred upper and lower boundaries,having diurnal variation.Premature beats showed separate layers(“stratification”),the layer number corresponding the number of RR-intervals.With simple premature beats,the layers were clearly separated.With parasystole rhythm,the upper and lower bands or layers might become thicker.With arial premature beats,the space or distance between layers varied.Ventricular premature beats presented equal space or distance between layers.With tachycardia,the lower layer became a“solid”layer.With atrial fibration,the“stratification”disappeared,presenting thicker or widened layers or bands,with neat lower boundary.With atrial flutter,the layers went parallel,with the layers being evenly separated or some distances being exact multiples of others.The second degree atrioventricular block displayed two layers,the lower and upper bands being equally away from the X-axis,presenting a straight line(pacing at a fixed rate)or a thicker or wider bands,with a neat upper boundary(the lowest pacing rate).When the scatter plot presented uncharacteristic patterns or had some scattered points,which rendered diagnosis difficult,a reverse technology could be used.Briefly,upon selection of scattered points,they were subjected to computerization,by regression,to reveal the piece of electrocardiogram(ECG)containing an R wave(QRS complex).Then ECG was analyzed to diagnose the cardiac rhythms.In conclusion,t-RR is a novel methodology which helps us understand heart rhythms from a new perspective.
基金National Natural Science Foundation of China,No.41301090
文摘Swidden agriculture is by far the dominant land use system in the uplands of Southeast Asia （SEA）, as well as other tropical regions, which plays an important role in the implementation of Reducing Emissions from Deforestation and Forest Degradation （REDD） of United Nations. To our knowledge, the long-term inter-annual area of newly burned plots （NBP） of swidden agriculture in mainland Southeast Asia is still not available, let alone in the whole tropics. With the strengthening regional geo-economic cooperation in SEA, swidden agriculture has experienced and/or is still experiencing extensive and drastic transformations into other diverse market-oriented land use types since the 1990s. In this study, high-level surface reflectance products of Landsat 4151718 family sensors including Thematic Mapper （TM）, Enhanced Thematic Mapper Plus （ETM＋） and Operational Land Imager （OLI） acquired in March, April and May of each year between 1988 and 2016 were firstly utilized to detect and monitor the extent and area of NBP of swidden agriculture with multiple thresholds of four commonly-used vegetation indices, namely the Normalized Difference Vegetation Index （NDVI）, Normalized Difference Moisture Index （NDMI）, Normalized Burn Ratio （NBR） and Soil Adjusted Vegetation Index （SAVI）, in combination with local phenological features of swid- dening and topographical data. The results showed that： （1） an annual average of 6.08×104 km2 of NBP of swidden agriculture, or 3.15% of the total land area of MSEA, were estimated in the past nearly three decades. （2） Annual NBP were primarily distributed in four major geomorphic units including the Central Range of Hills, Northern Mountainous Region, West- ern Myanmar Hills, and Annamite Chain. （3） A decadal average analysis indicated that the NBP of swidden agriculture opened year by year declined as a whole, especially after 2010, merely with an average of 5.23×104 km2. （4） The top ten provincial administrative units in Cambodia, Laos, Myanmar, Thailand and Vietnam, which consistently accounted for over 90% of the newly opened swiddens of each country, showed distinct fluctuations in usingslash-and-burn practices in the last decades. The Landsat-based （30 m） reconstructed 29-year longitudinal updated maps （including extent and area） of the NBP of swidden agri- culture may contribute to REDD and local livelihood related studies in Continental Southeast Asia. Our study further demonstrated that the multiple vegetative indices thresholds approach holds great potential in detecting swidden agriculture in tropical mountainous regions.
文摘There are many techniques using sensors and wearable devices for detecting and monitoring patients with Parkinson’s disease(PD).A recent development is the utilization of human interaction with computer keyboards for analyzing and identifying motor signs in the early stages of the disease.Current designs for classification of time series of computer-key hold durations recorded from healthy control and PD subjects require the time series of length to be considerably long.With an attempt to avoid discomfort to participants in performing long physical tasks for data recording,this paper introduces the use of fuzzy recurrence plots of very short time series as input data for the machine training and classification with long short-term memory(LSTM)neural networks.Being an original approach that is able to both significantly increase the feature dimensions and provides the property of deterministic dynamical systems of very short time series for information processing carried out by an LSTM layer architecture,fuzzy recurrence plots provide promising results and outperform the direct input of the time series for the classification of healthy control and early PD subjects.
基金This research is funded and supported by the Centre for Engineering Research and Development under the Research Seed Money scheme(CERD-RSM 2018 No.ME02 KTU/Research 2/3894/2018)of APJ Abdul Kalam Technological University,Thiruvanathapuram,Kerala State,India.
文摘The arrangement of natural and physical features on the earth’s surface are a few among the countless items that govern the airborne acoustic transmission at boundary layers.In particular,if the acoustic waves are attributes of live concerts at open-air theatres,without losing the sheen and quality,the audience should certainly receive the unbroken depth of the performance.Hence,at all times,it is advisable to analyse the auditory receptiveness,particularly in all intended recreational spaces.The current pandemic circumstances and the mandated COVID-19 prevention protocols encourage gatherings in naturally ventilated outdoor regions than confined indoors.This work predicts and quantifies the acoustic experience at the naturally carved amphitheatre at SAINTGITS,an autonomous institution at the down South-West of the Indian Subcontinent.The entire recreational space at SAINTGITS AMPHI was separately modelled as a Base case and Advanced case,and were analysed using the acoustic modelling module of EASE Focus,a renowned simulation freeware,which is in strict adherence with the International standards.The variation in loudness received at the nearest and farthest ends of the amphitheatre was between 67 to 80 dB.Though the Zero frequency SPL(Z-weighting)exhibited the loudness in the range of 81 to 85 dB and could maintain a safer auditory level for any human ear,it was confined to a hemispherical region near the sound source.A vertical beam angle of−4.0°was found to be effective throughout.The procedures and analyses will certainly help the future organizers and stakeholders to effectively plan the resources to reap rich acoustic experience at terrain-centric locales.The surface topography and contours were plotted with another set of freeware,the CADMAPPER and the QUIKGRID,to compare terrain gradient with the known data.Furthermore,this interdisciplinary research exhibits the extensive simulation capability of both EASE Focus and QUIKGRID and demonstrates the modelling versatility and deliverable potential of these freeware to benefit the budding architects and researchers.
基金Supported by National Basic Research Program of China （973 Program） （2009CB320602）, National Natural Science Foundation of China （60721003, 60736026）, and Changjiang Professorship by Ministry of Education of P. R. China
文摘A series of related electrophysiology phenomena can be caused by the occurrence of interpolated ventricular premature contraction.In our recent three-dimensional Lorenz R-R scatter plot research,we found that atrioventricular node double path caused by interpolated ventricular premature contraction imprints a specifi c pattern on three-dimensional Lorenz plots generated from 24-hour Holter recordings.We found two independent subclusters separated from the interpolated premature beat precluster,the interpolated premature beat cluster,and the interpolated premature beat postcluster,respectively.Combined with use of the trajectory tracking function and the leap phenomenon,our results reveal the presence of the atrioventricular node double conduction path.
文摘The parallel coordinate plot is proposed as an efficient tool for visualization of 13 traits of ＂stay-green＂ maize（Zea mays L.） cultivar exposed to different methods of magnesium application. The field experiment was conducted in the Department of Agronomy, Poznań University of Life Sciences, on the fields of the Department of Teaching and Experimental Station in Swadzim in 2006–2008. Experiment was conducted as a single-factor experiment with seven applications of magnesium in a randomized complete block design with four replicates. The highest mean values of grain yield and 1 000-grain weight were obtained after application of variant T3 of magnesium（10 kg MgO ha^–1 soil） in the all three years of study.
文摘Data from vegetation succession study is usually a matrix of plot × species × time.It is difficult to analyse this kind of data at present.A simple technique,clustercentering ordination is described in this paper,which can be used to analyse such a matrix directly.The data of 5 permanent plots in 7 years of inlands and grasslands in Kootwijki,the Netherlands,is analysed using this method as an application example.The results obviously illustrate the trend,direction and speedof community succession and can be easily interbrated.This suggests that clustercentering ordination is an effective and time-saving technique in study of vegetation succession.
文摘In order to study the dynamics of uneven-aged stands of interior Douglas-fir, Pseudotsuga menzesii var.glouca (Mirb.) Franco in future, six permanent sample plots wer set up on the Knife Creek Block of the Alex Fraser Researh Forcst of University of British Columbia. The measurements and observations for all living trees within theboundaries of a plot wer madc, including DBH(diameter at breast height), TTH(total tree height), height to lowest livingbranch, crown diameter, tree vigor, angle of lean, distance of lean, direction of lean and tree location. Based on the data,some stand characteristics of the plots were analyzed simply and preliminarily. Results showed that most of the interiortrees on the plots are ranged 10-20 cm in distribution of DBH class, and 2-6 m in distribution of rm class. Trees withdifferent fors, however, are distributed unevenly. The relationship between total tree height and diameter at breast heightfollows a quadratic distribution, Y=a+bX+cX2.
基金supported by the National Natural Science Foundation of China(Grants No.51569007 and 41301289)the Natural Science Foundation of Guangxi Province,China(Grant No.2015GXNSFCA139004)+1 种基金the Fund of the IRCK by UNESCO(Grant No.KDL201601)the Project of High Level Innovation Team and Outstanding Scholar in Guangxi Colleges and Universities(Grant No.002401013001)
文摘Although many sensitivity analyses using the soil and water assessment tool(SWAT) in a complex watershed have been conducted, little attention has been paid to the application potential of the model in unique plots. In addition, sensitivity analysis of percolation and evapotranspiration with SWAT has seldom been undertaken. In this study, SWAT99.2 was calibrated to simulate water balance components for unique plots in Southern China from 2000 to 2001, which included surface runoff, percolation, and evapotranspiration. Twenty-one parameters classified into four categories, including meteorological conditions, topographical characteristics, soil properties, and vegetation attributes, were used for sensitivity analysis through one-at-a-time(OAT) sampling to identify the factor that contributed most to the variance in water balance components. The results were shown to be different for different plots, with parameter sensitivity indices and ranks varying for different water balance components. Water balance components in the broad-leaved forest and natural grass plots were most sensitive to meteorological conditions, less sensitive to vegetation attributes and soil properties, and least sensitive to topographical characteristics. Compared to those in the natural grass plot, water balance components in the broad-leaved forest plot demonstrated higher sensitivity to the maximum stomatal conductance(GSI) and maximum leaf area index(BLAI).
文摘Aquifer test methods have greatly improved in recent years with the advent of inverse analysis, derivative analysis, and diagnostic plots. Updated analyses of past aquifer tests allow for improved interpretations of the data to enhance the knowledge and the predictive capabilities of the flow system. This work thoroughly reanalyzes a series of pre- and post-hydraulic fracturing, single-well aquifer tests conducted in two crystalline rock wells in New Hampshire as part of an early 1970’s study. Previous analyses of the data had relied on older manual type-curve methods for predicting the possible effects of hydraulic fracturing. This work applies inverse analysis, derivative analysis, and diagnostic plots to reanalyze the 1970’s aquifer test data. Our results demonstrate that the aquifer tests were affected by changes in flow regimes, dewatering of the aquifer and discrete fractures, and changes due to well development. Increases in transmissivities are related to well development prior to hydraulic fracturing, propagation of a single, vertical fracture hydraulically connecting the two wells after stimulation and expansion of troughs of depression. After hydraulic fracturing, the estimated total yield of the individual wells increased by 2.5 times due to the hydraulic fracturing. However, the wells may be receiving water from the same source, and well interference may affect any significant increase in their combined yield. Our analyses demonstrate the value in applying inverse analysis, derivative analysis, and diagnostic plots over the conventional method of manual type-curve analysis. In addition, our improvement in the aquifer test interpretation of the 1970’s test data has implications for more reliable estimates of sustained well yields.
基金National Natural Science Foundation of China(No.71371035)
文摘The two-parameter lognormal distribution is a variant of the normal distribution and the three-parameter lognormal distribution is an extension of the two-parameter lognormal distribution by introducing a location parameter. The Q-Q plot of the three-parameter lognormal distribution is widely used. To obtain the Q-Q plot one needs to iteratively try different values of the shape parameter and subjectively judge the linearity of the Q-Q plot. In this paper,a mathematical method was proposed to determine the value of the shape parameter so as to simplify the generation of the Q-Q plot. Then a new probability plot was proposed,which was more easily obtained and provided more accurate parameter estimates than the Q-Q plot. These are illustrated by three realworld examples.
文摘Given a sample of regression data from (Y, Z), a new diagnostic plotting method is proposed for checking the hypothesis H0: the data are from a given Cox model with the time-dependent covariates Z. It compares two estimates of the marginal distribution FY of Y. One is an estimate of the modified expression of FY under H0, based on a consistent estimate of the parameter under H0, and based on the baseline distribution of the data. The other is the Kaplan-Meier-estimator of FY, together with its confidence band. The new plot, called the marginal distribution plot, can be viewed as a test for testing H0. The main advantage of the test over the existing residual tests is in the case that the data do not satisfy any Cox model or the Cox model is mis-specified. Then the new test is still valid, but not the residual tests and the residual tests often make type II error with a very large probability.
文摘The use of Recurrence plots have been extensively used in various fields. In this work, Recurrence Plots (RPs) investigates the changes in the non-linear behaviour of urban air pollution using large datasets of raw data (hourly). This analysis has not been used before to extract information from large datasets for this type non-linear problem. Two different approaches have been used to tackle this problem. The first approach is to show results according to monitoring network. The second approach is to show the results by particle type. This analysis shows the feasibility of using Recurrence Analysis for pollution monitoring and control.
