Potential Areas for Commercial Timber Plantations of Tabebuia rosea(Bertol.)DC.in Michoacan,Mexico

The targeted area for plant reforestation in the state of Michoacan is made up of eroded areas and pasture induced areas, both adding to 525,260 ha and representing 10.9% of the total surface of the state. The regions with the largest areas in need of reforestation are the Costa with 185,396 ha (29%), Oriente with 106,836 (17%) and Tierra Caliente with 96,284 (15%). Commercial forest plantations are an alternative for reducing the pressure on natural forests and creating options for sustainable and diversified development, changing the land use from fragmented agricultur and livestock purposes to forestry. The object of this study was to determine potential areas for the establishment of commercial forest plantations of Tabebuia rosea (Bertol.) DC. in the state of Michoacan, Mexico, by using geographic information systems. The outlining of potential areas was performed with the IDRISI 32 and ArcView programs, according to the environmental requirements of T. rosea. These environmental requirements include precipitation, temperature, soil, altitude, land use and slope. The analysis resulted in two maps where the potential areas for the establishment of commercial forest plantations with this species were shown, which turned out a total potential area of 54,320 ha, distributed in 47,566 ha considering a slope of 0% - 15% for non-manual forest plantations, and 6754 ha considering a slope of 15% - 30% for manual forest plantations. The ecologic conditions in Michoacan are favorable for successful establishment and development of commercial forest plantations of T. rosea.

Areas with Potential for Commercial Timber Plantations of Enterolobium cyclocarpum (Jacq.) Griseb. in Michoacán, México

Michoacán has a deforested area of 525,260 ha, representing 52,526 ha per year, mainly caused by anthropogenic disturbances such as agricultural burning and forest fires (50%), change of use of land for extensive livestock farming (28%), agriculture (17%) and illegal logging (5%). The establishment of forest plantations is an alternative for reducing the pressure on natural forests and creating options for sustainable development and diversification of production and conversion of land for agricultural and livestock fragmented for forestry purposes. The aim of this study was to determine the potential areas for commercial forest plantations of Enterolobium cyclocarpum (Jacq.) Griseb. in the State of Michoacán, México, through the use of Geographic information systems (GIS). Areas were identified using IDRISI 32, and ArcView software. Screening variables include annual temperature, annual precipitation, land use, soil type, elevation and slope. Products obtained were field verified. Two maps where potential areas for the establishment of commercial forest plantations of E. cyclocarpum shown were obtained. Potential areas for commercial forest plantation establishment are (0% - 15% slope) for commercial forest plantations mechanized was 57,227 ha and (15% - 30% slope) for manual plantations was 6273 ha. The total area in the state with potential for the establishment of the species in the study was 63,500 ha.

Expected magnitude and distance of potential source area and the estimating method

Magnitude and distance of major potential source are needed in order to determine duration time of artificial ground motion and to determine the type of response spectrum (near field or far field) when using the seismic intensity zonation map. The magnitude probabilistic distribution function of seismic belt and the magnitude and space joint distribution function for given intensity of the site in a potential Source are provided. Then the basicformula of calculating expected magnitude and expected distance are developed. Several examples for calculating expected magnitude and expected distance in northern China are discussed. These results show that expected magnitude and expected distance are related not only to geometry of potential source and magnitude but also to the intensity of the site with certain exceeding probability.

Particle-in-Cell Simulation Study on the Floating Potential of Spacecraft in the Low Earth Orbit

In order to further understand the characteristics of the floating potential of low earth orbit spacecraft,the effects of the electron current collection area,background electron temperature,photocurrent emission,spacecraft wake,and the shape of spacecraft on spacecraft floating potential were studied here by particle-in-cell simulation in the low earth orbit.The simulation results show that the electron current collection area and background electron temperature impact on the floating potential by changing the electron current collection of spacecraft.By increasing the electron current collection area or background electron temperature,the spacecraft will float at a lower electric potential with respect to the surrounding plasma.However,the spacecraft wake affects the floating potential by increasing the ion current collected by spacecraft.The emission of the photocurrent from the spacecraft surface,which compensates for the electrons collected from background plasma,causes the floating potential to increase.The shape of the spacecraft is also an important factor influencing the floating potential.

Analysis on Uranium Mineralization Potential of Late Yanshanian Granites in Sichuan of Sanjiang Area

The Sanjiang area is an important granite distribution area in China,except for South China,in which granites is complex and complete.Based on fully collecting date about it,this paper explores the significance of uranium

Characterization,reactivity,source apportionment,and potential source areas of ambient volatile organic compounds in a typical tropical city

Based on one-year observation,the concentration,sources,and potential source areas of volatile organic compounds(VOCs)were comprehensively analyzed to investigate the pollution characteristics of ambient VOCs in Haikou,China.The results showed that the annual average concentration of total VOCs(TVOCs)was 11.4 ppb V,and the composition was dominated by alkanes(8.2 ppb V,71.4%)and alkenes(1.3 ppb V,20.5%).The diurnal variation in the concentration of dominant VOC species showed a distinct bimodal distribution with peaks in the morning and evening.The greatest contribution to ozone formation potential(OFP)was made by alkenes(51.6%),followed by alkanes(27.2%).The concentrations of VOCs and nitrogen dioxide(NO_(2))in spring and summer were low,and it was difficult to generate high ozone(O_(3))concentrations through photochemical reactions.The significant increase in O_(3)concentrations in autumn and winter was mainly related to the transmission of pollutants from the northeast.Traffic sources(40.1%),industrial sources(19.4%),combustion sources(18.6%),solvent usage sources(15.5%)and plant sources(6.4%)were identified as major sources of VOCs through the positive matrix factorization(PMF)model.The southeastern coastal areas of China were identified as major potential source areas of VOCs through the potential source contribution function(PSCF)and concentration-weighted trajectory(CWT)models.Overall,the concentration of ambient VOCs in Haikou was strongly influenced by traffic sources and long-distance transport,and the control of VOCs emitted from vehicles should be strengthened to reduce the active species of ambient VOCs in Haikou,thereby reducing the generation of O_(3).

基于GARP生态位模型的江西桔小实蝇适生区分析(英文)

[Objective] The paper was to provide the scientific basis for effective monitoring and early warning on oriental fruit fly in Jiangxi Province.[Method] Using the distribution data and environmental factor data of oriental fruit fly,the potential distribution area of oriental fruit fly in Jiangxi Province was predicted by GARP ecological niche model.[Result]The total suitable area for oriental fruit fly in Jiangxi province was over two thirds of the whole province.Most areas in southern Jiangxi basin ranged from 24° to 26° N were the high suitable area for oriental fruit fly,where the annual average temperature was 19-20℃.Part areas in north Ganzhou and small areas in southwest Ji＇an,Wuzhou,Yingtan,southeast Shangrao ranged from 26° to 27° N were the moderate suitable areas for oriental fruit fly,where the annual average temperature was 18-19℃.The low suitable area was ranged from 26° to 30° N including Binhu,Ganjiang River,Wuhe,Yuanshui area and Southwestern Mountain of Jiangxi Province,where the annual average temperature was 17-18℃.Northeast and northwest areas in Jiangxi Province and coastal areas along the Yangtze River was predicted to be non-suitable area for oriental fruit fly,where the annual average temperature was 16-17℃.[Conclusion] The results showed that the actual distribution of oriental fruit fly basically was consistent with the distribution predicted by GARP.

Seasonal variation of transport pathways and potential source areas at high inorganic nitrogen wet deposition sites in southern China

This study attempts to identify the dominant transport pathways,potential source areas,and their seasonal variation at sites with high inorganic nitrogen(IN)wet deposition flux in southern China.This is a long-term study(2010-2017)based on continuous deposition measurements at the Guangzhou urban site(GZ)and the Dinghushan Natural Reserve site(DHS)located in the Pearl River Delta(PRD)region.A dataset on monthly IN concentration in precipitation and wet deposition flux were provided.The average annual fluxes measured at both sites(GZ:33.04±9.52,DHS:20.52±10.22 kg N/(ha·year))were higher,while the ratios of reduced to oxidized N(GZ:1.19±0.77,DHS:1.25±0.84)were lower compared with the national mean level and the previous reported level throughout the PRD region.The dominant pathways were not always consistent with the highest proportional trajectory clusters.The transport pathways contributing most of deposition were identified in the north and northnortheast in the dry season and in the east-southeast,east,and south-southwest in the wet season.A weighted potential source contribution function(WPSCF)value>0.3 was determined reasonably to define the potential source area.Emission within the PRD region contributed the majority(≥95%at both sites)of the IN deposition in the wet season,while the contribution outside the region increased significantly in the dry season(GZ:27.86%,DHS:95.26%).Our results could help create more effective policy to control precursor emissions for IN fluxes,enabling reduction of the ecological risks due to excessive nitrogen.

Division of Gas Accumulation System and Laws Controlling Distribution of Natural Gas in Typical Petroliferous Basins of China

Considering the existing problems of the petroleum system, this paper bringsforward the concept of natural gas accumulation system and presents the dividing principles. Thendetailed statistics on the accumulation factors of the 32 typical natural gas accumulation systemsin China and studies on the laws controlling distribution of gas are collected. The research showsthat the petroleum accumulation system is the basic unit controlling petroleum generation, migrationand accumulation. Generating intensity, generating amount, accumulating efficiency and migrationdistance plays an important role in the distribution of natural gas. Through analysis on results ofresources evaluation, discovered reserves and residual reserves, potential areas in middle-scaledpetroliferous basins in China are forecasted in this paper. Ordos, Sichuan, Tarim and Qaidam basinsare found out to be the main basins developing and enriching gas accumulation systems.

Characterization of Fe-containing particles in Chengdu,southwest China,using single-particle aerosol mass spectrometry

Single-particle aerosol mass spectrometry was used to study the characteristics of Fecontaining particles during winter in Chengdu,southwest China.The mass concentrations of PM_(2.5)and PM_(10)during the study period were 64±38 and 89±49μg/m~3,respectively,and NO_(2)and particulate matter were high compared with most other regions of China.The Fecontaining particles were divided into seven categories with different mass spectra,sources and aging characteristics.The highest contribution was from Fe mixed with carbonaceous components(Fe-C,23.1%)particles.Fe was more mixed with sulfate than nitrate and therefore the contribution of Fe mixed with sulfate(Fe-S,20.7%)particles was higher than that of Fe mixed with nitrate(Fe-N,12.5%)particles.The contributions from Fe-containing particles related to primary combustion were high in the small particle size range,whereas aged Fecontaining particles and dust-related particles were mostly found in the coarse particle size range.The air masses mainly originated from the west and east of Chengdu,and the corresponding PM_(2.5)concentrations were 79±36 and 55±36μg/m~3,respectively.The west and east air masses showed stronger contributions of Fe-containing particles related to biomass burning(Fe-B)and fossil fuel combustion(Fe-C and Fe-S)particles,respectively.The southwest area contributed the most Fe-containing particles.Future assessments of the effects of Fe-containing particles during heavy pollution period should pay more attention to Fe-C and Fe-S particles.Emission-reduction of Fe-containing particles should consider both local emissions and short-distance transmission from the surrounding areas.

Mapping rice-fallow cropland areas for short-season grain legumes intensification in South Asia using MODIS 250 m time-series data

The goal of this study was to map rainfed and irrigated rice-fallow cropland areas across South Asia,using MODIS 250 m time-series data and identify where the farming system may be intensified by the inclusion of a short-season crop during the fallow period.Rice-fallow cropland areas are those areas where rice is grown during the kharif growing season(June–October),followed by a fallow during the rabi season(November–February).These cropland areas are not suitable for growing rabi-season rice due to their high water needs,but are suitable for a short-season(≤3 months),low water-consuming grain legumes such as chickpea(Cicer arietinum L.),black gram,green gram,and lentils.Intensification(double-cropping)in this manner can improve smallholder farmer’s incomes and soil health via rich nitrogen-fixation legume crops as well as address food security challenges of ballooning populations without having to expand croplands.Several grain legumes,primarily chickpea,are increasingly grown across Asia as a source of income for smallholder farmers and at the same time providing rich and cheap source of protein that can improve the nutritional quality of diets in the region.The suitability of rainfed and irrigated rice-fallow croplands for grain legume cultivation across South Asia were defined by these identifiers:(a)rice crop is grown during the primary(kharif)crop growing season or during the north-west monsoon season(June–October);(b)same croplands are left fallow during the second(rabi)season or during the south-east monsoon season(November–February);and(c)ability to support low water-consuming,short-growing season(≤3 months)grain legumes(chickpea,black gram,green gram,and lentils)during rabi season.Existing irrigated or rainfed crops such as rice or wheat that were grown during kharif were not considered suitable for growing during the rabi season,because the moisture/water demand of these crops is too high.The study established cropland classes based on the every 16-day 250 m normalized difference vegetation index(NDVI)time series for one year(June 2010–May 2011)of Moderate Resolution Imaging Spectroradiometer(MODIS)data,using spectral matching techniques(SMTs),and extensive field knowledge.Map accuracy was evaluated based on independent ground survey data as well as compared with available sub-national level statistics.The producers’and users’accuracies of the cropland fallow classes were between 75%and 82%.The overall accuracy and the kappa coefficient estimated for rice classes were 82%and 0.79,respectively.The analysis estimated approximately 22.3 Mha of suitable rice-fallow areas in South Asia,with 88.3%in India,0.5%in Pakistan,1.1%in Sri Lanka,8.7%in Bangladesh,1.4%in Nepal,and 0.02%in Bhutan.Decision-makers can target these areas for sustainable intensification of short-duration grain legumes.

Hunting of hunted:an ensemble modeling approach to evaluate suitable habitats for caracals in India

Background:Large-scale hunting and various anthropogenic pressures in the recent past have pushed the Asiatic caracal(Caracal caracal schmitzi),an elusive medium-sized and locally threatened felid species towards local extinction in India.Though widely distributed historically,it has been sparsely reported from several regions of central and northern states in India till twentieth century.Later,the species distribution became confined only to the states of Rajasthan,Gujarat and Madhya Pradesh,which have had reported sightings in the twenty-first century.In order to highlight the potentially suitable habitats for Asiatic caracals in India,we targeted forth-filtering of the spatial model ensemble by creating and utilizing the validated and spatially thinned species presence information(n=69)and related ecological variables(aridity,NDVI,precipitation seasonality,temperature seasonality,terrain ruggedness),filtered with anthropological variable(nightlight).Results:Out of eight spatial prediction models,the two most parsimonious models,Random Forest(AUC 0.91)and MaxEnt(AUC 0.89)were weighted and ensembled.The ensemble model indicated several clustered habitats,covering 1207.83 km^(2)areas in Kachchh(Gujarat),Aravalli mountains(Rajasthan),Malwa plateau(Rajasthan and Madhya Pradesh),and Bundelkhand region(Madhya Pradesh)as potentially suitable habitats for caracals.Output probabilities of pixels were further regressed with converted vegetation height data within selected highly potential habitats,i.e.,Ranthambore Kuno Landscape(RKL)(suitability~0.44+0.03(vegetation height)^(**),R^(2)=0.27).The regression model inferred a significant positive relation between vegetation height and habitat suitability,hence the lowest ordinal class out of three classes of converted vegetation height was masked out from the RKL,which yielded in an area of 567 km^(2) as potentially highly suitable habitats for caracals,which can be further proposed as survey areas and conservation priority areas for caracals.Conclusion:The study charts out the small pockets of landscape in and around dryland protected areas,suitable for caracal in the Indian context,which need attention for landscape conservation.