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Scientific analysis of indigenous techniques for guggal(Commiphora wightii) tapping in India

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Journal of Forestry Research 2014年第3期25卷 695-700页

作者： Jatindra Nath Samanta Kunal Mandla Directorate of Medicinal & Aromatic Plants Research Borivai Anand Gujarat–387310 India Directorate Mushroom Research Chambaghat Solan – 173213 India

Guggal, a threatened species that is endemic to western India, is tapped to extract medicinally important oleo-gum-resin （guggul）. However, the plant dies after gum exudation. The indigenous tapping techniques used by local people were examined in Gujarat, India to dis-cover the scientific basis behind these techniques： selection of gum in-ducer, season of tapping, and plant parts to be tapped. First, the presence of Xanthomonas axonopodis pv. commiphorae （Xac） in the gum suspen-sion used for tapping was established. This bacterium induces gum ooz-ing from the tapped plants and later, causes them to die off. The popula-tion of Xac in gum was found to decrease with the age of the gum. With that, fresh gum increased the tapping success. Second, local people pre-ferred tapping during the warm season, which we validated by determin-ing that Xac growth was best at 30 ＆#176;C. Tapping during September （mean temperature 25.7-30.0 ＆#176;C） clearly favoured growth of the pathogen and yielded maximum guggul. Multiple tapping on a mature tree ensured maximum gum extraction before its death. Finally, application of in-digenous technology under natural plant stands by the local people en-sured availability of this important raw drug for consumption. Our study established that the age-old traditional methods have a strong scientific basis. However, it is imperative to formulate strategies based on con-temporary scientific understanding to protect this natural resource before it becomes extinct.

关键词： Burseraceae gummosis medicinal plant participatory forest management xerophytes

Carbon dioxide fluxes of tundra vegetation communities on an esker top in the low-Arctic

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Advances in Polar Science 2020年第3期31卷 167-177页

作者： Peter M.LAFLEUR A.Brett CAMPEAU Sohee KANG School of the Environment Trent UniversityPeterboroughOntarioCanada Geography Department Trent UniversityPeterboroughOntarioCanada Department of Computer and Mathematical Sciences University of Toronto ScarboroughTorontoOntarioCanada

Previous studies have shown that carbon dioxide fluxes vary considerably among Arctic environments and it is important to assess these differences in order to develop our understanding of the role of Arctic tundra in the global carbon cycle. Although many previous studies have examined tundra carbon dioxide fluxes, few have concentrated on elevated terrain(hills and ridge tops) that is exposed to harsh environmental conditions resulting in sparse vegetation cover and seemingly low productivity. In this study we measured carbon dioxide(CO2) exchange of four common tundra communities on the crest of an esker located in the central Canadian low-Arctic. The objectives were to quantify and compare CO2 fluxes from these communities, investigate responses to environmental variables and qualitatively compare fluxes with those from similar communities growing in less harsh lowland tundra environments. Measurements made during July and August 2010 show there was little difference in net ecosystem exchange(NEE) and gross ecosystem production(GEP) among the three deciduous shrub communities, Arctous alpina, Betula glandulosa and Vaccinium uliginosum, with means ranging from -4.09 to -6.57 μmol·m^-2·s^-1 and -7.92 to -9.24 μmol·m^-2·s^-1, respectively. Empetrum nigrum communities had significantly smaller mean NEE and GEP(-1.74 and -4.08 μmol·m^-2·s^-1, respectively). Ecosystem respiration(ER) was similar for all communities(2.56 to 3.03 μmol·m^-2·s^-1), except the B. glandulosa community which had a larger mean flux(4.66 μmol·m^-2·s^-1). Overall, fluxes for these esker-top communities were near the upper range of fluxes reported for other tundra communities. ER was related to soil temperature in all of the communities. Only B. glandulosa GEP and ER showed sensitivity to a persistent decline in soil moisture throughout the study. These findings may have important implications for how esker tops would be treated in construction of regional carbon budgets and for predicting the im

关键词： tundra carbon exchange net ecosystem exchange gross ecosystem productivity ecosystem respiration low-Arctic esker top xerophytes

Adaptive responses to drought of two Retama raetam subspecies from Tunisia

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Journal of Plant Ecology 2021年第3期14卷 527-540页

作者： Ricardo Gil Dhikra Zayoud Zeineb Ouerghi Monica Boscaiu Oscar Vicente Mohamed Neffati Instituto de Biologfa Molecular y Celular de Plantas(IBMCP UPV-CSIC)Universitat Politecnica de Valencia46022 ValenciaSpain Laboratoire des Ecosystemes Pastoraux et Valorisation des Plantes Spontanees et des Micro-organismes Associes Institut des Regions AridesUniversite de Gabes4119 MedenineTunisia Departement de Biologie Faculte des Sciences de Tunis1060 TunisTunisia Instituto Agroforestal Mediterraneo(IAM) Universitat Politecnica de Valencia46022 ValenciaSpain Instituto de Conservacion y Mejora de la Agrodivcrsidad Valenciana(COMAV) Universitat Politecnica de Valencia46022 ValenciaSpain

Aims The survival and ecological distribution of plants in arid habitats are mainly conditioned by water availability and physiological adaptations to withstand *** the present study,we have compared the physiological responses to drought of two Retama raetam(retama)subspecies from Tunisia,one of them living under the desert climate(***)and the other one growing on the coast(***).Methods To physiologically characterize the two *** subspecies,and to elucidate their main mechanisms underlying their tolerance to drought stress,parameters related to seed germination,growth,photosynthesis(net photosynthetic rate,intracellular CO_(2) concentration,transpiration rate,stomatal conductance and water-use efficiency)and accumulation of osmolytes(proline,glycine betaine[GB]and soluble sugars)were determined in 4-month-old plants subjected to stress for up to 1 *** Findings Drought significantly inhibited germination,growth and all the evaluated photosynthetic *** of *** *** were severely affected by drought after 3 weeks of treatment when photosynthesis rates were up to 7-fold lower than in the *** the same time,proline and GB significantly accumulated compared with the irrigated controls,but much less than in *** ***;in the latter subspecies,proline and GB increased to levels 24-and 6-fold higher,respectively,than in the corresponding *** summary,the population living in the desert region exhibited stronger tolerance to drought stress than that adapted to the semiarid littoral climate,suggesting that tolerance in *** is dependent on accumulation of osmolytes.

关键词： germination leaf gas exchange osmolytes Retama raetam water stress xerophytes

Soil Characteristics Influence the Selection of Dominant Plant Genotypes Inhabiting Wadi Sudr, Egypt

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American Journal of Plant Sciences 2016年第8期7卷 1304-1315页

作者： Esraa Attia El Sherbeny Amal Ahmed Morsy Mahmoud Magdy Genetics Resources Department Desert Research Center Ministry of Agriculture Cairo Egypt Botany Department Faculty of Science Ain Shams University Cairo Egypt Genetics Department Faculty of Agriculture Ain Shams University Cairo Egypt

Rangeland plant community and species composition are known to be related to specific soil properties. The current study investigated the ecological influence (soil characteristics) on the selection and distribution of ecological-related genotypes of dominant xerophyte species in WadiSudr of Egypt. AFLP analysis reflected the genetic profile of the samples species from two altitudinal ranges (up and midstream) and was compared statistically with the differences of their inhabiting soil characteristics on two depth levels (20 and 40 cm) using Mantel test. Correlation values (r) ranged from 0.585 - 0.778 when treating the physical and chemical properties of soil samples regardless its altitudinal area. The correlation confirms that the soil chemical and physical properties influence the selection of a certain genotypes of the dominant xerophytes plants collected from Wadi Sudr of Egypt to certain altitude, while depths at 20 and 40 cm play a key role in the early growth and then the colonization of the selected genotypes, respectively. More studies are needed to exactly test the role and the importance of each of the correlated property to the plant growth and colonization.

关键词： xerophytes Wadi Sudr-Egypt Soil Characteristics F-AFLP Mantel Test

High Vegetation of Lake Ayakagitma in Bukhara Region and Their Distribution

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American Journal of Plant Sciences 2022年第11期13卷 1373-1380页

作者： Shamsiyev Naim Amonovich Qobilov Aziz Muxtorovich Bukhara State University Bukhara Uzbekistan

More than 500 lakes are found in Uzbekistan. Ayakagitma Lake is located on the border of the Northern Gijduvon and Shafirkon districts of Bukhara region. This lake was formed in 1985-1986 at the expense of the waters of the sewage dump collector. The area of the lake is 8200 hectares, the maximum depth is 35 m, on average 10 - 15 m, the minimum is 3 - 5 meters. The chemical composition of lake water is chloride-sulfate and has a calcareous character. 67 species of high plants belonging to 22 families were found in this area. 17 of these species are found in the water of the lake and 50 species are found around it. Of the most common species, Phragmites communis reach a height of 4.5 - 5.5 meters. Phragmites communis make up the total area of the lake 8 - 10 hectares.

关键词： Mesotrophic Zooplankton Zoobentos Nectobentos Bentos Detritus Mesophytes xerophytes Hygrophytes Biomass

Degradation of the Vegetation Cover in Central Mongolia: A Case Study

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Journal of Resources and Ecology 2015年第2期6卷 73-78页

作者： Bair Z. TSYDYPOV Endon Zh. GARMAEV Arnold K. TULOKHONOV Eduard A. BATOTSYRENOV Alexander A. AYURZHANAEV Zhargalma B. ALYMBAEVA Ts. CHIMEDDORJ 俄罗斯科学院西伯利亚分院贝加尔自然管理研究所蒙古国立农业大学

Two model polygons in the Central Mongolia are considered for investigation of vegetation dynamics. They are located in rainless climatic zones -- arid and semiarid. For the emphasized polygons plots of the NDVI temporal variation and NDVI maps of its multi-temporal values on the base of Landsat TM imagery are constructed. The full-scale landscape indication of the selected NDVI areas with different values with the step through 0.1 is conducted. This indication is supported by the analysis of vegetation to environmental groups for drought resistance. Almost the entire territory of the emphasized polygons vegetation digression during this period was traced. The analysis of the time variation of NDVI shows a decrease of its values. This indicates a trend xerophytization already sparse vegetation of Gobi. In the semiarid climatic zone a digression vegetation trend is directly related to heavy load on the pastures.

关键词： desertification vegetation degradation arid semiarid Landsat NDVI landscape indication xerophytes