Azadirachta indica seed samples were collected from four different agro-ecological regions(AERs) viz.,AER-2,AER-4,AER-5A and AER-5B of Gujarat state,India during 2000 to 2002 with an aim to assess variability in aza...Azadirachta indica seed samples were collected from four different agro-ecological regions(AERs) viz.,AER-2,AER-4,AER-5A and AER-5B of Gujarat state,India during 2000 to 2002 with an aim to assess variability in azadirachtin,oil and fatty acids content of the seeds and assess correlation of these parameters with morphological characters.Azadirachtin,oil and fatty acids content indicated significant(p0.01) variations between years and AERs in Gujarat.The azadirachtin ranged from 142 to 9 527 μg·g-1 seed kernel with an average of 2 426 μg·g-1 for the state.AER-5B recorded highest azadirachtin and oil content.Fatty acid composition was found to be affected by environmental factors particularly varying degree of annual rainfall and temperature during fruit ripening period.Conclusively trees growing in AER-5B performed better in term of azadirachtin,oil and stearic acid content.Tree girth at breast height showed no significant relation with these biochemicals.展开更多
The changes in species composition, abundance and forest stand structure were analyzed across altitudinal regimes in tropical forests of Eastern Ghats of northern Andhra Pradesh, India. Three 1-ha plots were establish...The changes in species composition, abundance and forest stand structure were analyzed across altitudinal regimes in tropical forests of Eastern Ghats of northern Andhra Pradesh, India. Three 1-ha plots were established with one each in low, medium and high altitudes. A total of 153 species, 2129 stems (709 stems .ha^-1) of ≥10 cm girth were enumerated. Species richness and diversity pattern varied along altitudinal gradient and increased with the altitude. Species richness varied from 52 to 110 species-ha^-1 and stand density from 639 to 836 stems.ha^-1 with average basal area of 34.39 m^2.ha^-1. Shannon-Wiener index (H') ranged from 4.55 to 5.17. Low altitude (i.e., Site 1) is dominated byXylia xylocarpa (59.22) and Lagerstroemia parviflora (23.90), medium altitude (i.e., Site 2) by Xylia xylocarpa (45;50) Bursera serrata (17.29), and high altitude (i.e., Site 3) has Schleichera oleosa (28.25) Pterocarpus marsupium (26.55) as predominant species. Taxonomically, Rubiaceae (12 species), Fabaceae (12), Euphorbiaceae (11), Rutaceae (7) and Lanraceae (7) were dominant families. Density-wise, Fabaceae, Combretaceae, Euphorbiaceae, Anacardiaceae and Myrtaceae were abundant. Thus, conservation assessment based on altitudinal regimes and the information on species structure and function can provide baseline information for monitoring and sustaining the biodiversity.展开更多
The purpose of this study was to classify current forest cover types,and to investigate stand development patterns for natural forests in six areas in northern Baekdudaegan,South Korea.Twenty-eight independent forest ...The purpose of this study was to classify current forest cover types,and to investigate stand development patterns for natural forests in six areas in northern Baekdudaegan,South Korea.Twenty-eight independent forest communities were aggregated into eight forest cover types by species composition in the overstory of each forest community.The forest cover types were of mixed mesophytic,‘‘others’ ’ deciduous,Quercus mongolica dominant,Q.mongolica pure,Pinus densiflora–Q.mongolica,P.densiflora,Betula ermanii,and Q.mongolica–P.koraiensis.The ecological information was organized by importance value and species diversity for each forest type.Based on the correlation between species diversity index and the abundance of Q.mongolica plus P.densiflora for corresponding forest cover types,we compared the developmental process and approximate successional pathway between each cover type.The P.densiflora forest cover type changes into the P.densiflora–Q.mongolica cover type,followed by the Q.mongolica dominant cover type through continuous invasion of the oak trees.Furthermore,the Q.mongolica pure cover type would spread toward the Q.mongolica dominant cover type with a mixture of various deciduous tree species.The Q.mongolica dominant cover type progresses through the other deciduous cover types to the mixed mesophytic cover type with diversified composition and structure.On the mid to lower slopes,with loamy soils and good moisture conditions,various deciduous forest types should progress,by ecological succession,toward the mixed mesophytic cover type without any further disturbance.展开更多
The semi-arid mangroves of the Gulf of Kachchh,the largest ecosystems on the west coast of India,are poorly studied in terms of vegetation structure and environmental parameters in spite of their conservation signific...The semi-arid mangroves of the Gulf of Kachchh,the largest ecosystems on the west coast of India,are poorly studied in terms of vegetation structure and environmental parameters in spite of their conservation significance.Therefore,it is necessary to document the structural features of these mangroves in view of ongoing coastal industrial development.Mangrove forest structure in 10 locations on the northern and southern coasts of the Gulf of Kachchh were assessed using the line intercept transect method.Descriptions included density of young and mature age classes,tree heights,diameters at breast height(DBH)and aboveground biomass,along with seven significant environmental variables.Mature tree densities ranged from 350 to 1567 ind.ha-1,while average height and girth at breast height ranged from 1.0 to 6.8 m and 3.0 to 137.0 cm,respectively.The majority of trees(55.6%)were in B 1.8 m height class followed by a 1.9 to 2.4 m class(25.1%).DBH was most often in class 2 cm or lower than that.Among the canopy index classes,more trees were recorded in class ≤2 cm.The regeneration density was greater than the recruitment class.This study indicates that the poor structural attributes of Avicennia marina Vierth.var.acutissima Stapf and Mold dominated mangroves are largely due to aridity induced by scarce and erratic rainfall and high soil and water salinities.The results should be valuable in conserving and sustainably managing these mangroves in the face of developmental activities.展开更多
The status of the names, Physalis minima L. and P. maxima Mill. (Solanaceae), and their alleged presence on the Indian subcontinent are discussed. The issues of nativity and identity of Linnaean Physalis minima are lo...The status of the names, Physalis minima L. and P. maxima Mill. (Solanaceae), and their alleged presence on the Indian subcontinent are discussed. The issues of nativity and identity of Linnaean Physalis minima are long-debated while the use of the name P. maxima Mill. and its report from India are recent. The available evidence indicates that the name "P. minima L." is misapplied to two different elements, viz., P. angulata L. and P. lagascae Roem. & Schult. The name Physalis minima L. may be rejected as nomen confusum, for which the paper provides the primary information. As on today, it is submerged under the synonymy of P. angulata L. The correct name for the widely known P. minima is P. lagascae. The name "P. maxima Mill." applied to the escape and naturalized weed in the Indian subcontinent and elsewhere is to be substituted by P. pruinosa L., a name misapplied to P. grisea (Waterf.) M. Martínez.展开更多
The Lower Saxonian Elbe Valley Biosphere Reserve is part of the UNESCO Biosphere Reserve “Elbe River Landscape”, and used mainly for agriculture. One of tasks of the Biosphere Reserve Administration is to develop su...The Lower Saxonian Elbe Valley Biosphere Reserve is part of the UNESCO Biosphere Reserve “Elbe River Landscape”, and used mainly for agriculture. One of tasks of the Biosphere Reserve Administration is to develop sustainable forms of land use which requires comprehensive updated land cover maps. Land use maps are hard to produce because of surveying costs and time. Nevertheless, these large areas need to be monitored. TerraSAR-X images are used to establish agricultural land use maps. In this study, two areas are selected within the Elbe Biosphere Reserve situated around the oxbows Wehninger Werder and Walmsburger Werder. Multi temporal classification methods were used to identify the different crops using maximum likelihood classifier for the years 2010 and 2011. The crop classifications were used to evaluate the effect of the number of images, the necessity of polarizations, and the consequences of some missing images within the crop calendar. These classifications were analyzed to estimate producer accuracy and Kappa index for each crop besides the overall accuracy for each agricultural land use map. The study shows that using dual polarization imagery enhances producer accuracies for many crops over the single polarization imagery, and demonstrates the importance of using frequent images during the cultivation period.展开更多
Egypt is considered as an extremely arid country with annual rainfall under 200 mm within coastal zones. High Aswan Dam Reservoir (HADR) experiences high evaporation losses of 15 BCM/year on average. Meanwhile, the wa...Egypt is considered as an extremely arid country with annual rainfall under 200 mm within coastal zones. High Aswan Dam Reservoir (HADR) experiences high evaporation losses of 15 BCM/year on average. Meanwhile, the water demand is increasing due to rapid population growth. Hence, measurements must be taken to decrease its evaporation losses. This can be achieved through controlling evaporation losses from the shallow lagoons, locally known as khors. The first step in the control process is to model the lake morphology using topographic data. Topographic maps are available for the time span before the construction of the High Aswan DAM (HAD), but they have not been updated. Hence, this study utilized satellite imagery since 1984 to develop a digital elevation model (DEM) that simulated the lake surface area. Correlated water levels were gained from the assembled hydrological database of HADR. This paper reports on the different alternatives for reducing the evaporation losses of two large khors, Kalabsha and El-Alaky, and two small khors, Korosko and Sara. It shows that the developed DEM allows estimation of the different hydrological features of HADR and its khors and recommends some measures to eliminate these khors to save up to 3 BCM by 2100 according to global climate model scenarios.展开更多
Forests are considered as a sacred asset in India and have guided the way of living throughout its history.Indian forests not only accommodate the myriad species but also act as a survival support system to the commun...Forests are considered as a sacred asset in India and have guided the way of living throughout its history.Indian forests not only accommodate the myriad species but also act as a survival support system to the communities that depended on them.The 2030 Agenda for Sustainable Development proposed by the United Nations(UN)has gained momentum and becomes an integral part of the recent efforts of Indian governance.In this investigation,we examined the potential nexus between Indian forestry system(biodiversity-enriched assets,ecosystem services,constitutional mechanisms,and governances)and Sustainable Development Goals(SDGs)through theoretical underpinnings from literature that selected from database like Google Scholar,Indian forest survey reports,and information retrieved from Indian government websites.The significance of this review is that it presents comprehensive information about Indian forestry,biodiversity-rich assets,and sustainable forest management practices.The results show that Indian forestry as a whole is an integral part of the food-energy-water cycle and contributes to all dimensions of sustainable development,i.e.,economic sustainability,social sustainability,and environmental sustainability.The investigation confirms that besides partly contributing to the economy and life support systems to many dependent species,forests also act as boosters in the areas of food security and health.Targets related to the climate action,peace,and partnership goals are well in place through various forestry interventions and environmental commitments by the Government of India.展开更多
Lake Michigan, the sixth largest freshwater lake in the world by surface area, was utilized as a water body for assessment. Field data collected at sampling sites throughout the lake in an intensive monitoring effort ...Lake Michigan, the sixth largest freshwater lake in the world by surface area, was utilized as a water body for assessment. Field data collected at sampling sites throughout the lake in an intensive monitoring effort were utilized for evaluation of the distribution of sediment measurements. An assessment of sediment nutrient and carbon measurements within Lake Michigan was completed to recognize strata resulting from the hydrodynamics of the system. Nonparametric comparison tests revealed that significant differences exist between measurements of sediment nutrients and organic carbon in the lake using strata based upon water column depth (all results demon-strated a p < 0.05, α = 0.05). Cross-validation analysis was applied to the field-collected samples, revealing that large errors occur when estimating sediment flux of carbon or nutrients at a given location in the lake without considering stratification of the distributions of these measurements. Errors in estimating sediment concentrations of nutrients and carbon specific to a location in the lake demonstrated a statistically significant increase when stratification of sediment measurements wasn’t employed among sites. For example, distributions of errors in estimating all nutrients and organic carbon concentrations, whereby distance squared inverse interpolation methods were applied, demonstrated a statistically significant increase in absence of stratification (all p < 0.001, α = 0.05). These results have implications for characterization, monitoring, and modeling sediment and water interaction as related to eutrophication, as well as to contaminant exposure and bioaccumulation for chemicals within Lake Michigan and large water bodies where stratification of the sediment based upon physics of the system exists.展开更多
Visual signals, including changes in coloration and color patterns, are frequently used by animalsto convey information. During contests, body coloration and its changes can be used to assess anopponent's state or mo...Visual signals, including changes in coloration and color patterns, are frequently used by animalsto convey information. During contests, body coloration and its changes can be used to assess anopponent's state or motivation. Communication of aggressive propensity is particularly importantin group-living animals with a stable dominance hierarchy, as the outcome of aggressive inter-actions determines the social rank of group members. Neolamprologus pulcher is a cooperativelybreeding cichlid showing frequent within-group aggression. Both sexes exhibit two vertical blackstripes on the operculum that vary naturally in shape and darkness. During frontal threat displaysthese patterns are actively exposed to the opponent, suggesting a signaling function. To investi-gate the role of operculum stripes during contests we manipulated their darkness in computeranimated pictures of the fish. We recorded the responses in behavior and stripe darkness of testsubjects to which these animated pictures were presented. Individuals with initially darker stripeswere more aggressive against the animations and showed more operculum threat displays.Operculum stripes of test subjects became darker after exposure to an animation exhibiting a paleoperculum than after exposure to a dark operculum animation, highlighting the role of the dark-ness of this color pattern in opponent assessment. We conclude that (i) the black stripes on theoperculum of N. pulcherare a reliable signal of aggression and dominance, (ii) these markings playan important role in opponent assessment, and (iii) 2D computer animations are well suited to elicitbiologically meaningful short-term aggressive responses in this widely used model system ofsocial evolution.展开更多
Tropical forests have been recognized as having global conservation importance. However,they are being rapidly destroyed in many regions of the world. Regular monitoring of forests is necessary for an adaptive managem...Tropical forests have been recognized as having global conservation importance. However,they are being rapidly destroyed in many regions of the world. Regular monitoring of forests is necessary for an adaptive management approach and the successful implementation of ecosystem management. The present study analyses the temporal changes in forest ecosystem structure in tribal dominated Malkangiri district of Orissa,India,during 1973-2004 period based on digitized forest cover maps using geographic information system (GIS) and interpretation of satellite data. Three satellite images Landsat MSS (1973),Landsat TM (1990) and IRS P6 LISS III (2004) were used to determine changes. Six land cover types were delineated which includes dense forest,open forest,scrub land,agriculture,barren land and water body. Different forest types were also demarcated within forest class for better understanding the degradation pattern in each forest types. The results showed that there was a net decrease of 475.7 km2 forest cover (rate of deforestation = 2.34) from 1973 to 1990 and 402.3 km2 (rate of deforestation = 2.27) from 1990 to 2004. Forest cover has changed over time depending on a few factors such as large-scale deforestation,shifting cultivation,dam and road construction,unregulated management actions,and social pressure. A significant increase of 1222.8 km2 agriculture area (1973-2004) clearly indicated the conversion of forest cover to agricultural land. These alterations had resulted in significant environmental consequences,including decline in forest cover,soil erosion,and loss of biodiversity. There is an urgent need for rational management of the remaining forest for it to be able to survive beyond next decades. Particular attention must be paid to tropical forests,which are rapidly being deforested.展开更多
Permafrost is an important component in hydrological processes because changes in runoff over the Arctic drainage basin cannot be well explained by changes in precipitation-related variables.However,current understand...Permafrost is an important component in hydrological processes because changes in runoff over the Arctic drainage basin cannot be well explained by changes in precipitation-related variables.However,current understanding of the influences of permafrost on hydrological dy-namics is insufficient.This study investigated historical variations in permafrost conditions and their potential hydrologic effects over the Russian Arctic drainage basin.The results show that soil temperature(at 0.40 m below surface)has increased about 1.4℃over the Ob,1.5℃over the Yenisei,and 1.8℃over the Lena River basin from 1936 through 2013,possibly resulted in a significant thawing of permafrost.Rapid active layer changes have occurred since the 1970s.The volume of the active layer increased by 28,142,and 228 km3 over the Ob,Yenisei,and Lena basins,respectively,since the 1970s.Melting ground ice caused by deepening active layer may be a limited contribution to annual runoff.Runoff during freeze season(October--April)showed significant positive correlations(p<0.05)to active layer thickness in the Yenisei and Lena basins while negative correlation(p>0.05)in the Ob basin.These results imply that,in basins with high permafrost coverage,a deeper active layer increased soil water storage capacity and perhaps contribute to an increase in winter runoff.展开更多
Naphthenic acids are a complex class of thousands of naturally occurring aliphatic and alicyclic carboxylic acids found in oil sands bitumen and in the wastewater generated from bitumen processing. Dozens of analytica...Naphthenic acids are a complex class of thousands of naturally occurring aliphatic and alicyclic carboxylic acids found in oil sands bitumen and in the wastewater generated from bitumen processing. Dozens of analytical methods have been developed for the semiquantification of total naphthenic acids in water samples. However, different methods can give different results, prompting investigation into the comparability of the many methods. A review of important methodological features for analyzing total naphthenic acids is presented and informs the design of future standard methods for the semi- quantification of total naphthenic acids using mass spectrometry. The design considerations presented are a synthesis of discussions from an Environment and Climate Change Canada (ECCC) led taskforce of 10 laboratory experts from government, industry and academia during April 2016 and subsequent discussions between University of British Columbia and ECCC representatives. Matters considered are: extraction method, solvent, pH, and temperature; analysis instrumentation and resolution; choice of calibration standards; use of surrogate and internal standards; and use of online or offline separation prior to analysis. The design considerations are amenable to both time-of-flight and Orbitrap mass spectrometers.展开更多
Poly-and perfluoroalkyl substances(PFASs)are important environmental contaminants globally and in the early 2000s they were shown to be ubiquitous contaminants in Arctic wildlife.Previous reviews by Butt et al.and Let...Poly-and perfluoroalkyl substances(PFASs)are important environmental contaminants globally and in the early 2000s they were shown to be ubiquitous contaminants in Arctic wildlife.Previous reviews by Butt et al.and Letcher et al.have covered studies on levels and trends of PFASs in the Arctic that were available to 2009.The purpose of this review is to focus on more recent work,generally published between 2009 and 2018,with emphasis on PFASs of emerging concern such as perfluoroalkyl carboxylates(PFCAs)and short-chain perfluoroalkyl sulfonates(PFSAs)and their precursors.Atmospheric measurements over the period 2006e2014 have shown that fluorotelomer alcohols(FTOHs)as well as perfluorobutanoic acid(PFBA)and perfluoroctanoic acid(PFOA)are the most prominent PFASs in the arctic atmosphere,all with increasing concentrations at Alert although PFOA concentrations declined at the Zeppelin Station(Svalbard).Results from ice cores show generally increasing deposition of PFCAs on the Devon Ice cap in the Canadian arctic while declining fluxes were found in a glacier on Svalbard.An extensive dataset exists for long-term trends of long-chain PFCAs that have been reported in Arctic biota with some datasets including archived samples from the 1970s and 1980s.Trends in PFCAs over time vary among the same species across the North American Arctic,East and West Greenland,and Svalbard.Most long term time series show a decline from higher concentrations in the early 2000s.However there have been recent(post 2010)increasing trends of PFCAs in ringed seals in the Canadian Arctic,East Greenland polar bears and in arctic foxes in Svalbard.Annual biological sampling is helping to determine these relatively short term changes.Rising levels of some PFCAs have been explained by continued emissions of long-chain PFCAs and/or their precursors and inflows to the Arctic Ocean,especially from the North Atlantic.While the effectiveness of biological sampling for temporal trends in long-chain PFCAs and PFSAs has been demonstrated,this does not apply to the C4eC8ePFCAs,perfluorobutane sulfonamide(FBSA),or perfluorobutane sulfonate(PFBS)which are generally present at low concentrations in biota.In addition to air sampling,sampling abiotic media such as glacial cores,and annual sampling of lake waters and seawater would appear to be the best approaches for investigating trends in the less bioaccumulative PFASs.展开更多
The recent realistic estimate of fungal numbers which used various algorithms was between 2.2 and 3.8 million.There are nearly 100,000 accepted species of Fungi and fungus-like taxa,which is between 2.6 and 4.5%of the...The recent realistic estimate of fungal numbers which used various algorithms was between 2.2 and 3.8 million.There are nearly 100,000 accepted species of Fungi and fungus-like taxa,which is between 2.6 and 4.5%of the estimated species.Several forums such as Botanica Marina series,Fungal Diversity notes,Fungal Biodiversity Profiles,Fungal Systematics and Evolution-New and Interesting Fungi,Mycosphere notes and Fungal Planet have enhanced the introduction of new taxa and nearly 2000 species have been introduced in these publications in the last decade.The need to define a fungal species more accurately has been recognized,but there is much research needed before this can be better clarified.We address the evidence that is needed to estimate the numbers of fungi and address the various advances that have been made towards its understanding.Some genera are barely known,whereas some plant pathogens comprise numerous species complexes and numbers are steadily increasing.In this paper,we examine ten genera as case studies to establish trends in fungal description and introduce new species in each genus.The genera are the ascomycetes Colletotrichum and Pestalotiopsis(with many species or complexes),Atrocalyx,Dothiora,Lignosphaeria,Okeanomyces,Rhamphoriopsis,Thozetella,Thyrostroma(rela-tively poorly studied genera)and the basidiomycete genus Lepiota.We provide examples where knowledge is incomplete or lacking and suggest areas needing further research.These include(1)the need to establish what is a species,(2)the need to establish how host-specific fungi are,not in highly disturbed urban areas,but in pristine or relatively undisturbed forests,and(3)the need to establish if species in different continents,islands,countries or regions are different,or if the same fungi occur worldwide?Finally,we conclude whether we are anywhere near to flattening the curve in new species description.展开更多
Seaweed bioinvasions increasingly affect coastal environments around the world, which increases the need for predictive models and mitigation strategies. The biotic interactions between seaweed invaders and invaded co...Seaweed bioinvasions increasingly affect coastal environments around the world, which increases the need for predictive models and mitigation strategies. The biotic interactions between seaweed invaders and invaded communities are often considered a key determinant of invasion success and failure and we here revise the current evidence that the capacity of seaweed invaders to deter enemies in newly reached environments correlates with their invasion success. Particularly efficient chemical defences have been described for several of the more problematic seaweed invaders during the last decades. However, confirmed cases in which seaweed invaders confronted un-adapted enemies in newly gained environments with deterrents that were absent from these environments prior to the invasion (so-called “novel weapons”) are scarce, although an increasing number of invasive and non-invasive seaweeds are screened for defence compounds. More evidence exists that seaweeds may adapt defence intensities to changing pressure by biological enemies in newly invaded habitats. However, most of this evidence of shifting defence was gathered with only one particular model seaweed, the Asia-endemic red alga Agarophyton vermiculophyllum, which is particularly accessible for direct comparisons of native and non-native populations in common garden experiments. A. vermiculophyllum interacts with consumers, epibionts and bacterial pathogens and in most of these interactions, non-native populations have rather gained than lost defensive capacity relative to native conspecifics. The increases in the few examined cases were due to an increased production of broad-spectrum deterrents and the relative scarcity of specialized deterrents perhaps reflects the circumstance that seaweed consumers and epibionts are overwhelmingly generalists.展开更多
文摘红藻真江蓠(Gracilaria vermiculophylla)是西北太平洋地区特有种,但在过去100年间它借助海运(太平洋牡蛎养殖)快速入侵到北美、欧洲和地中海等沿海栖息地,对当地的生物多样性、海洋环境和生态系统等造成重大影响。为从分子水平初步了解真江蓠成功入侵的潜在机制,文章对其入侵起源地——日本北部的真江蓠及非入侵种——绳状龙须菜(Gracilariopsis chorda)进行了同质园实验(common garden experiment)处理后的比较转录组研究,以探究该地区入侵属性不同的两种红藻间的基因表达差异。结果表明,真江蓠和绳状龙须菜共有基因序列集(Universal Gene,unigene)主要集中在核糖体、嘌呤和嘧啶代谢等通路。其中,在真江蓠中光系统II反应中心蛋白D1(photosystem II reaction center protein D1)、细胞色素P450单加氧酶(cytochrome P450 monooxygenase)和核酮糖1,5二磷酸羧化酶大亚基(Ribulose bisphosphate carboxylase large subunit,rbcL)等基因的表达量显著上调,而逆转录转座子蛋白(retrotransposon protein)、细胞壁相关的水解酶(cell wall-associated hydrolase)和金属离子转运蛋白Nramp5的表达既上调也下调。与光合作用过程相关基因的大量表达可能有助于真江蓠应对逆境胁迫,特别是光系统ⅡD1反应中心蛋白表达量升高可能有助于藻体修复光系统Ⅱ复合体,从而制造更多的有机物以备藻体生长所需。而金属离子转运蛋白Nramp5等的上调和下调则表明江蓠等红藻可能通过某些基因表达量的增减对不同的环境变动作出响应。总体而言,代谢过程中的资源再分配很可能是驱动真江蓠适应和耐受新的生境的主要分子机制。
基金supported by the NOVOD Board, Ministry of Agriculture, Government of India
文摘Azadirachta indica seed samples were collected from four different agro-ecological regions(AERs) viz.,AER-2,AER-4,AER-5A and AER-5B of Gujarat state,India during 2000 to 2002 with an aim to assess variability in azadirachtin,oil and fatty acids content of the seeds and assess correlation of these parameters with morphological characters.Azadirachtin,oil and fatty acids content indicated significant(p0.01) variations between years and AERs in Gujarat.The azadirachtin ranged from 142 to 9 527 μg·g-1 seed kernel with an average of 2 426 μg·g-1 for the state.AER-5B recorded highest azadirachtin and oil content.Fatty acid composition was found to be affected by environmental factors particularly varying degree of annual rainfall and temperature during fruit ripening period.Conclusively trees growing in AER-5B performed better in term of azadirachtin,oil and stearic acid content.Tree girth at breast height showed no significant relation with these biochemicals.
文摘The changes in species composition, abundance and forest stand structure were analyzed across altitudinal regimes in tropical forests of Eastern Ghats of northern Andhra Pradesh, India. Three 1-ha plots were established with one each in low, medium and high altitudes. A total of 153 species, 2129 stems (709 stems .ha^-1) of ≥10 cm girth were enumerated. Species richness and diversity pattern varied along altitudinal gradient and increased with the altitude. Species richness varied from 52 to 110 species-ha^-1 and stand density from 639 to 836 stems.ha^-1 with average basal area of 34.39 m^2.ha^-1. Shannon-Wiener index (H') ranged from 4.55 to 5.17. Low altitude (i.e., Site 1) is dominated byXylia xylocarpa (59.22) and Lagerstroemia parviflora (23.90), medium altitude (i.e., Site 2) by Xylia xylocarpa (45;50) Bursera serrata (17.29), and high altitude (i.e., Site 3) has Schleichera oleosa (28.25) Pterocarpus marsupium (26.55) as predominant species. Taxonomically, Rubiaceae (12 species), Fabaceae (12), Euphorbiaceae (11), Rutaceae (7) and Lanraceae (7) were dominant families. Density-wise, Fabaceae, Combretaceae, Euphorbiaceae, Anacardiaceae and Myrtaceae were abundant. Thus, conservation assessment based on altitudinal regimes and the information on species structure and function can provide baseline information for monitoring and sustaining the biodiversity.
基金support of ‘Forest Science&Technology Projects(Project No.S211012L030110)’ provided by Korea Forest Service
文摘The purpose of this study was to classify current forest cover types,and to investigate stand development patterns for natural forests in six areas in northern Baekdudaegan,South Korea.Twenty-eight independent forest communities were aggregated into eight forest cover types by species composition in the overstory of each forest community.The forest cover types were of mixed mesophytic,‘‘others’ ’ deciduous,Quercus mongolica dominant,Q.mongolica pure,Pinus densiflora–Q.mongolica,P.densiflora,Betula ermanii,and Q.mongolica–P.koraiensis.The ecological information was organized by importance value and species diversity for each forest type.Based on the correlation between species diversity index and the abundance of Q.mongolica plus P.densiflora for corresponding forest cover types,we compared the developmental process and approximate successional pathway between each cover type.The P.densiflora forest cover type changes into the P.densiflora–Q.mongolica cover type,followed by the Q.mongolica dominant cover type through continuous invasion of the oak trees.Furthermore,the Q.mongolica pure cover type would spread toward the Q.mongolica dominant cover type with a mixture of various deciduous tree species.The Q.mongolica dominant cover type progresses through the other deciduous cover types to the mixed mesophytic cover type with diversified composition and structure.On the mid to lower slopes,with loamy soils and good moisture conditions,various deciduous forest types should progress,by ecological succession,toward the mixed mesophytic cover type without any further disturbance.
基金financially supported by the Marine National Park and Sanctuary(MNP&S)Jamnagar,Gujarat State,India through the project,"Mangrove Vegetation Characteristics of Gulf of Kachchh"
文摘The semi-arid mangroves of the Gulf of Kachchh,the largest ecosystems on the west coast of India,are poorly studied in terms of vegetation structure and environmental parameters in spite of their conservation significance.Therefore,it is necessary to document the structural features of these mangroves in view of ongoing coastal industrial development.Mangrove forest structure in 10 locations on the northern and southern coasts of the Gulf of Kachchh were assessed using the line intercept transect method.Descriptions included density of young and mature age classes,tree heights,diameters at breast height(DBH)and aboveground biomass,along with seven significant environmental variables.Mature tree densities ranged from 350 to 1567 ind.ha-1,while average height and girth at breast height ranged from 1.0 to 6.8 m and 3.0 to 137.0 cm,respectively.The majority of trees(55.6%)were in B 1.8 m height class followed by a 1.9 to 2.4 m class(25.1%).DBH was most often in class 2 cm or lower than that.Among the canopy index classes,more trees were recorded in class ≤2 cm.The regeneration density was greater than the recruitment class.This study indicates that the poor structural attributes of Avicennia marina Vierth.var.acutissima Stapf and Mold dominated mangroves are largely due to aridity induced by scarce and erratic rainfall and high soil and water salinities.The results should be valuable in conserving and sustainably managing these mangroves in the face of developmental activities.
文摘The status of the names, Physalis minima L. and P. maxima Mill. (Solanaceae), and their alleged presence on the Indian subcontinent are discussed. The issues of nativity and identity of Linnaean Physalis minima are long-debated while the use of the name P. maxima Mill. and its report from India are recent. The available evidence indicates that the name "P. minima L." is misapplied to two different elements, viz., P. angulata L. and P. lagascae Roem. & Schult. The name Physalis minima L. may be rejected as nomen confusum, for which the paper provides the primary information. As on today, it is submerged under the synonymy of P. angulata L. The correct name for the widely known P. minima is P. lagascae. The name "P. maxima Mill." applied to the escape and naturalized weed in the Indian subcontinent and elsewhere is to be substituted by P. pruinosa L., a name misapplied to P. grisea (Waterf.) M. Martínez.
文摘The Lower Saxonian Elbe Valley Biosphere Reserve is part of the UNESCO Biosphere Reserve “Elbe River Landscape”, and used mainly for agriculture. One of tasks of the Biosphere Reserve Administration is to develop sustainable forms of land use which requires comprehensive updated land cover maps. Land use maps are hard to produce because of surveying costs and time. Nevertheless, these large areas need to be monitored. TerraSAR-X images are used to establish agricultural land use maps. In this study, two areas are selected within the Elbe Biosphere Reserve situated around the oxbows Wehninger Werder and Walmsburger Werder. Multi temporal classification methods were used to identify the different crops using maximum likelihood classifier for the years 2010 and 2011. The crop classifications were used to evaluate the effect of the number of images, the necessity of polarizations, and the consequences of some missing images within the crop calendar. These classifications were analyzed to estimate producer accuracy and Kappa index for each crop besides the overall accuracy for each agricultural land use map. The study shows that using dual polarization imagery enhances producer accuracies for many crops over the single polarization imagery, and demonstrates the importance of using frequent images during the cultivation period.
文摘Egypt is considered as an extremely arid country with annual rainfall under 200 mm within coastal zones. High Aswan Dam Reservoir (HADR) experiences high evaporation losses of 15 BCM/year on average. Meanwhile, the water demand is increasing due to rapid population growth. Hence, measurements must be taken to decrease its evaporation losses. This can be achieved through controlling evaporation losses from the shallow lagoons, locally known as khors. The first step in the control process is to model the lake morphology using topographic data. Topographic maps are available for the time span before the construction of the High Aswan DAM (HAD), but they have not been updated. Hence, this study utilized satellite imagery since 1984 to develop a digital elevation model (DEM) that simulated the lake surface area. Correlated water levels were gained from the assembled hydrological database of HADR. This paper reports on the different alternatives for reducing the evaporation losses of two large khors, Kalabsha and El-Alaky, and two small khors, Korosko and Sara. It shows that the developed DEM allows estimation of the different hydrological features of HADR and its khors and recommends some measures to eliminate these khors to save up to 3 BCM by 2100 according to global climate model scenarios.
文摘Forests are considered as a sacred asset in India and have guided the way of living throughout its history.Indian forests not only accommodate the myriad species but also act as a survival support system to the communities that depended on them.The 2030 Agenda for Sustainable Development proposed by the United Nations(UN)has gained momentum and becomes an integral part of the recent efforts of Indian governance.In this investigation,we examined the potential nexus between Indian forestry system(biodiversity-enriched assets,ecosystem services,constitutional mechanisms,and governances)and Sustainable Development Goals(SDGs)through theoretical underpinnings from literature that selected from database like Google Scholar,Indian forest survey reports,and information retrieved from Indian government websites.The significance of this review is that it presents comprehensive information about Indian forestry,biodiversity-rich assets,and sustainable forest management practices.The results show that Indian forestry as a whole is an integral part of the food-energy-water cycle and contributes to all dimensions of sustainable development,i.e.,economic sustainability,social sustainability,and environmental sustainability.The investigation confirms that besides partly contributing to the economy and life support systems to many dependent species,forests also act as boosters in the areas of food security and health.Targets related to the climate action,peace,and partnership goals are well in place through various forestry interventions and environmental commitments by the Government of India.
文摘Lake Michigan, the sixth largest freshwater lake in the world by surface area, was utilized as a water body for assessment. Field data collected at sampling sites throughout the lake in an intensive monitoring effort were utilized for evaluation of the distribution of sediment measurements. An assessment of sediment nutrient and carbon measurements within Lake Michigan was completed to recognize strata resulting from the hydrodynamics of the system. Nonparametric comparison tests revealed that significant differences exist between measurements of sediment nutrients and organic carbon in the lake using strata based upon water column depth (all results demon-strated a p < 0.05, α = 0.05). Cross-validation analysis was applied to the field-collected samples, revealing that large errors occur when estimating sediment flux of carbon or nutrients at a given location in the lake without considering stratification of the distributions of these measurements. Errors in estimating sediment concentrations of nutrients and carbon specific to a location in the lake demonstrated a statistically significant increase when stratification of sediment measurements wasn’t employed among sites. For example, distributions of errors in estimating all nutrients and organic carbon concentrations, whereby distance squared inverse interpolation methods were applied, demonstrated a statistically significant increase in absence of stratification (all p < 0.001, α = 0.05). These results have implications for characterization, monitoring, and modeling sediment and water interaction as related to eutrophication, as well as to contaminant exposure and bioaccumulation for chemicals within Lake Michigan and large water bodies where stratification of the sediment based upon physics of the system exists.
文摘Visual signals, including changes in coloration and color patterns, are frequently used by animalsto convey information. During contests, body coloration and its changes can be used to assess anopponent's state or motivation. Communication of aggressive propensity is particularly importantin group-living animals with a stable dominance hierarchy, as the outcome of aggressive inter-actions determines the social rank of group members. Neolamprologus pulcher is a cooperativelybreeding cichlid showing frequent within-group aggression. Both sexes exhibit two vertical blackstripes on the operculum that vary naturally in shape and darkness. During frontal threat displaysthese patterns are actively exposed to the opponent, suggesting a signaling function. To investi-gate the role of operculum stripes during contests we manipulated their darkness in computeranimated pictures of the fish. We recorded the responses in behavior and stripe darkness of testsubjects to which these animated pictures were presented. Individuals with initially darker stripeswere more aggressive against the animations and showed more operculum threat displays.Operculum stripes of test subjects became darker after exposure to an animation exhibiting a paleoperculum than after exposure to a dark operculum animation, highlighting the role of the dark-ness of this color pattern in opponent assessment. We conclude that (i) the black stripes on theoperculum of N. pulcherare a reliable signal of aggression and dominance, (ii) these markings playan important role in opponent assessment, and (iii) 2D computer animations are well suited to elicitbiologically meaningful short-term aggressive responses in this widely used model system ofsocial evolution.
基金Acknowledgments O.B-T is supported by a Fulbright post-doctoral fellowship from the United States - Israel Educational Foundation. This study was funded by an Israel Science Foundation (ISF) grant 1397/10 and by the Israel Nature and Park Authority. We thank R. King and A. Dolev for their help during various phases of the project. This is publication number 844 of the Mitrani Department of Desert Ecology.
文摘Tropical forests have been recognized as having global conservation importance. However,they are being rapidly destroyed in many regions of the world. Regular monitoring of forests is necessary for an adaptive management approach and the successful implementation of ecosystem management. The present study analyses the temporal changes in forest ecosystem structure in tribal dominated Malkangiri district of Orissa,India,during 1973-2004 period based on digitized forest cover maps using geographic information system (GIS) and interpretation of satellite data. Three satellite images Landsat MSS (1973),Landsat TM (1990) and IRS P6 LISS III (2004) were used to determine changes. Six land cover types were delineated which includes dense forest,open forest,scrub land,agriculture,barren land and water body. Different forest types were also demarcated within forest class for better understanding the degradation pattern in each forest types. The results showed that there was a net decrease of 475.7 km2 forest cover (rate of deforestation = 2.34) from 1973 to 1990 and 402.3 km2 (rate of deforestation = 2.27) from 1990 to 2004. Forest cover has changed over time depending on a few factors such as large-scale deforestation,shifting cultivation,dam and road construction,unregulated management actions,and social pressure. A significant increase of 1222.8 km2 agriculture area (1973-2004) clearly indicated the conversion of forest cover to agricultural land. These alterations had resulted in significant environmental consequences,including decline in forest cover,soil erosion,and loss of biodiversity. There is an urgent need for rational management of the remaining forest for it to be able to survive beyond next decades. Particular attention must be paid to tropical forests,which are rapidly being deforested.
基金the National Key R&D Program of China(2019YFA0607003,2019YFC1509100)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA20100313,XDA20100103)the National Science Foundation,United States(1503559).
文摘Permafrost is an important component in hydrological processes because changes in runoff over the Arctic drainage basin cannot be well explained by changes in precipitation-related variables.However,current understanding of the influences of permafrost on hydrological dy-namics is insufficient.This study investigated historical variations in permafrost conditions and their potential hydrologic effects over the Russian Arctic drainage basin.The results show that soil temperature(at 0.40 m below surface)has increased about 1.4℃over the Ob,1.5℃over the Yenisei,and 1.8℃over the Lena River basin from 1936 through 2013,possibly resulted in a significant thawing of permafrost.Rapid active layer changes have occurred since the 1970s.The volume of the active layer increased by 28,142,and 228 km3 over the Ob,Yenisei,and Lena basins,respectively,since the 1970s.Melting ground ice caused by deepening active layer may be a limited contribution to annual runoff.Runoff during freeze season(October--April)showed significant positive correlations(p<0.05)to active layer thickness in the Yenisei and Lena basins while negative correlation(p>0.05)in the Ob basin.These results imply that,in basins with high permafrost coverage,a deeper active layer increased soil water storage capacity and perhaps contribute to an increase in winter runoff.
文摘Naphthenic acids are a complex class of thousands of naturally occurring aliphatic and alicyclic carboxylic acids found in oil sands bitumen and in the wastewater generated from bitumen processing. Dozens of analytical methods have been developed for the semiquantification of total naphthenic acids in water samples. However, different methods can give different results, prompting investigation into the comparability of the many methods. A review of important methodological features for analyzing total naphthenic acids is presented and informs the design of future standard methods for the semi- quantification of total naphthenic acids using mass spectrometry. The design considerations presented are a synthesis of discussions from an Environment and Climate Change Canada (ECCC) led taskforce of 10 laboratory experts from government, industry and academia during April 2016 and subsequent discussions between University of British Columbia and ECCC representatives. Matters considered are: extraction method, solvent, pH, and temperature; analysis instrumentation and resolution; choice of calibration standards; use of surrogate and internal standards; and use of online or offline separation prior to analysis. The design considerations are amenable to both time-of-flight and Orbitrap mass spectrometers.
基金We thank the Arctic Monitoring and Assessment Programme(AMAP)and the national programs in the circumpolar countries for their funding and support of this work.We are especially grateful to Simon Wilson,Cynthia de Wit,and the reviewers that read the chapter on PFASs in the original AMAP assessment.We are thankful to the northern communities in circumpolar regions for their cooperation and collection of biological samples that yielded the data reviewed here.DCGM was supported by the King Carl XVI Gustaf Professorship in Environmental Science at the Dept of Environmental Science and Analytical Chemistry,Stockholm University during 2018-19.
文摘Poly-and perfluoroalkyl substances(PFASs)are important environmental contaminants globally and in the early 2000s they were shown to be ubiquitous contaminants in Arctic wildlife.Previous reviews by Butt et al.and Letcher et al.have covered studies on levels and trends of PFASs in the Arctic that were available to 2009.The purpose of this review is to focus on more recent work,generally published between 2009 and 2018,with emphasis on PFASs of emerging concern such as perfluoroalkyl carboxylates(PFCAs)and short-chain perfluoroalkyl sulfonates(PFSAs)and their precursors.Atmospheric measurements over the period 2006e2014 have shown that fluorotelomer alcohols(FTOHs)as well as perfluorobutanoic acid(PFBA)and perfluoroctanoic acid(PFOA)are the most prominent PFASs in the arctic atmosphere,all with increasing concentrations at Alert although PFOA concentrations declined at the Zeppelin Station(Svalbard).Results from ice cores show generally increasing deposition of PFCAs on the Devon Ice cap in the Canadian arctic while declining fluxes were found in a glacier on Svalbard.An extensive dataset exists for long-term trends of long-chain PFCAs that have been reported in Arctic biota with some datasets including archived samples from the 1970s and 1980s.Trends in PFCAs over time vary among the same species across the North American Arctic,East and West Greenland,and Svalbard.Most long term time series show a decline from higher concentrations in the early 2000s.However there have been recent(post 2010)increasing trends of PFCAs in ringed seals in the Canadian Arctic,East Greenland polar bears and in arctic foxes in Svalbard.Annual biological sampling is helping to determine these relatively short term changes.Rising levels of some PFCAs have been explained by continued emissions of long-chain PFCAs and/or their precursors and inflows to the Arctic Ocean,especially from the North Atlantic.While the effectiveness of biological sampling for temporal trends in long-chain PFCAs and PFSAs has been demonstrated,this does not apply to the C4eC8ePFCAs,perfluorobutane sulfonamide(FBSA),or perfluorobutane sulfonate(PFBS)which are generally present at low concentrations in biota.In addition to air sampling,sampling abiotic media such as glacial cores,and annual sampling of lake waters and seawater would appear to be the best approaches for investigating trends in the less bioaccumulative PFASs.
基金the Thailand Research Fund for the grant RDG6130001MS Impact of climate change on fungal diversity and biogeography in the Greater Mekong SubregionCalabon is grateful to the Mushroom Research Foundation,Department of Science and Technology-Science Education Institute,and Plant Genetic Conservation Project under the Royal Initiation of Her Royal Highness Princess Maha Chakri Sirindhorn-Mae Fah Luang University+11 种基金the Royal Golden Jubilee PhD Program under Thailand Research Fund(RGJ)no.PHD/0002/2560.Chayanard Phukhamsakda would like to thank the Royal Golden Jubilee PhD Program under Thailand Research Fund(RGJ)for a personal grant to C.Phukhamsakda(The scholarship no.PHD/0020/2557 to study towards a PhD)Saowaluck Tibpromma would like to thank the International Postdoctoral Exchange Fellowship Program(number Y9180822S1),CAS President’s International Fellowship Initiative(PIFI)(number 2020PC0009),China Postdoctoral Science Foundation and the Yunnan Human Resources,and Social Security Department Foundation for funding her postdoctoral researchMingkwan Doilom would like to thank the 5th batch of Postdoctoral Orientation Training Personnel in Yunnan Province(grant no.:Y934283261)the 64th batch of China Post-doctoral Science Foundation(grant no.:Y913082271)Yusufjon Gafforov thanks the Ministry of Innovative Development of the Republic of Uzbekistan(Projects,no.P3-2014-0830174425P3-20170921183),CAS President’s International Fellowship Initiative(PIFI)for Visiting Scientist(Grant No.:2018VBB0021)The research is also supported by the project of National Natural Science Foundation of China(Nos.31560489,31972222)Program of Introducing Talents of Discipline to Universities of China(111 Program,D20023)National Key Technology Research and Development Program of the Ministry of Science and Technology of China(2014BAD23B03/03)Talent project of Guizhou Science and Technology Cooperation Platform([2017]5788-5)Guizhou Science,Technology Department International Cooperation Basic Project([2018]5806).E.B.Gareth Jones is supported under the Distinguished Scientist Fellowship Program(DSFP),King Saud University,Kingdom of Saudi Arabia.R.Phookamsak thanks CAS President’s International Fellowship Initiative(PIFI)for young staff(grant no.Y9215811Q1),the National Science Foundation of China(NSFC)project code 31850410489(grant no.Y81I982211)and Chiang Mai University for their financial support.N.Thongklang would like to thank the Thailand research fund grants“Study of saprobic Agaricales in Thailand to find new industrial mushroom products”(Grant No.DBG6180015)K.D.Hyde and N.Thongklang thank to Thailand Science Research and Innovation(TSRI)grant,Macrofungi diversity research from the Lancang-Mekong Watershed and surrounding areas(Grant No.DBG6280009).
文摘The recent realistic estimate of fungal numbers which used various algorithms was between 2.2 and 3.8 million.There are nearly 100,000 accepted species of Fungi and fungus-like taxa,which is between 2.6 and 4.5%of the estimated species.Several forums such as Botanica Marina series,Fungal Diversity notes,Fungal Biodiversity Profiles,Fungal Systematics and Evolution-New and Interesting Fungi,Mycosphere notes and Fungal Planet have enhanced the introduction of new taxa and nearly 2000 species have been introduced in these publications in the last decade.The need to define a fungal species more accurately has been recognized,but there is much research needed before this can be better clarified.We address the evidence that is needed to estimate the numbers of fungi and address the various advances that have been made towards its understanding.Some genera are barely known,whereas some plant pathogens comprise numerous species complexes and numbers are steadily increasing.In this paper,we examine ten genera as case studies to establish trends in fungal description and introduce new species in each genus.The genera are the ascomycetes Colletotrichum and Pestalotiopsis(with many species or complexes),Atrocalyx,Dothiora,Lignosphaeria,Okeanomyces,Rhamphoriopsis,Thozetella,Thyrostroma(rela-tively poorly studied genera)and the basidiomycete genus Lepiota.We provide examples where knowledge is incomplete or lacking and suggest areas needing further research.These include(1)the need to establish what is a species,(2)the need to establish how host-specific fungi are,not in highly disturbed urban areas,but in pristine or relatively undisturbed forests,and(3)the need to establish if species in different continents,islands,countries or regions are different,or if the same fungi occur worldwide?Finally,we conclude whether we are anywhere near to flattening the curve in new species description.
基金sponsored by the Sino-German Center Science Center,Beijing,China,(GZ1357)the National Key R&D Program of China(2018YFD0900305).
文摘Seaweed bioinvasions increasingly affect coastal environments around the world, which increases the need for predictive models and mitigation strategies. The biotic interactions between seaweed invaders and invaded communities are often considered a key determinant of invasion success and failure and we here revise the current evidence that the capacity of seaweed invaders to deter enemies in newly reached environments correlates with their invasion success. Particularly efficient chemical defences have been described for several of the more problematic seaweed invaders during the last decades. However, confirmed cases in which seaweed invaders confronted un-adapted enemies in newly gained environments with deterrents that were absent from these environments prior to the invasion (so-called “novel weapons”) are scarce, although an increasing number of invasive and non-invasive seaweeds are screened for defence compounds. More evidence exists that seaweeds may adapt defence intensities to changing pressure by biological enemies in newly invaded habitats. However, most of this evidence of shifting defence was gathered with only one particular model seaweed, the Asia-endemic red alga Agarophyton vermiculophyllum, which is particularly accessible for direct comparisons of native and non-native populations in common garden experiments. A. vermiculophyllum interacts with consumers, epibionts and bacterial pathogens and in most of these interactions, non-native populations have rather gained than lost defensive capacity relative to native conspecifics. The increases in the few examined cases were due to an increased production of broad-spectrum deterrents and the relative scarcity of specialized deterrents perhaps reflects the circumstance that seaweed consumers and epibionts are overwhelmingly generalists.