The Tunisian coastal oases constitute a model of very rich plant biodiversity, organized in different floors of cultivation. The date palm is the highest, the second is the diversified fruit trees and the smallest is ...The Tunisian coastal oases constitute a model of very rich plant biodiversity, organized in different floors of cultivation. The date palm is the highest, the second is the diversified fruit trees and the smallest is composed by various other productions. The present paper is the results of a RAA diagnosis and bibliographic analysis of nearly thirty years of work on oases. The aim of this study is to focus on the plant diversity and the traditions in using different products. The survey revealed the existence of nearly 45 local date palm varieties, about 26 fruit trees, 65 vegetables and divers other species. It also raises nearly 30 uses of dates and date palm by-products. This survey shows also that oases inhabitants keep in possessing, for a long time, a knowledge to make ingenious concerning use and conservation of the products and by products of the date palm. This survey has all as much demonstrated the risks from weakening this balance which has long been maintained. Some recommendations to maintain and conserve this system are also presented in this paper.展开更多
Through analysis of the historical and present development of botanical gardens, both domestic and international, with particular focus on botanical garden practices within the Chinese Academy of Sciences (CAS), the a...Through analysis of the historical and present development of botanical gardens, both domestic and international, with particular focus on botanical garden practices within the Chinese Academy of Sciences (CAS), the authors propose that science-based botanical gardens (which differ from common public gardens), should be founded on plant diversity inventory and ex-situ conservation of wild plant species. Efforts should be directed to rarer species from biodiversity-rich areas and biodiversity hotspots, utilizing cutting-edge technologies to effectively preserve germplasm in living collections. Science-based botanical garden management should be directed by sound scientific evaluation of plant resources and guaranteed by innovative operational mechanisms. Science-based botanical gardens should also emphasize the establishment of identifiable and specialized living collections, research platforms and recruitment of qualified experts. In addition to curating living specimens, science-based botanical gardens should pursue research and development of new plant varieties or patents based on their plant collections, thus providing continual support to bio-industry.展开更多
Mint is a medicinal and aromatic plant. It is very important for the pharmacopoeia, perfumes, confectionery and liquor industry. Some green mint leaves without rods are used as samples. Physical and mechanical propert...Mint is a medicinal and aromatic plant. It is very important for the pharmacopoeia, perfumes, confectionery and liquor industry. Some green mint leaves without rods are used as samples. Physical and mechanical properties of the sample such as the desorption isotherms, the density and volumetric withdrawal are determined. The kinetics of drying, where it follows the changes of the water content of the sample as a function of the drying time for the three temperatures 30, 40 and 50℃, is also presented and discussed.展开更多
This study investigated the influence of broadleaf and conifer vegetation on soil microbial communities in a distinct vertical distribution belt in Northeast China.Soil samples were taken at 0-5,5-10 and 10-20 cm dept...This study investigated the influence of broadleaf and conifer vegetation on soil microbial communities in a distinct vertical distribution belt in Northeast China.Soil samples were taken at 0-5,5-10 and 10-20 cm depths from four vegetation types at different altitudes,which were characterized by poplar(Populus davidiana)(1250-1300 m),poplar(P.davidiana) mixed with birch(Betula platyphylla)(1370-1550 m),birch(B.platyphylla)(1550-1720 m),and larch(Larix principis-rupprechtii)(1840-1890 m).Microbial biomass and community structure were determined using the fumigation-extraction method and phospholipid fatty acid(PLFA) analysis,and soil fungal community level physiological profiles(CLPP) were characterized using Biolog FF Microplates.It was found that soil properties,especially soil organic carbon and water content,contributed significantly to the variations in soil microbes.With increasing soil depth,the soil microbial biomass,fungal biomass,and fungal catabolic ability diminished;however,the ratio of fungi to bacteria increased.The fungal ratio was higher under larch forests compared to that under poplar,birch,and their mixed forests,although the soil microbial biomass was lower.The direct contribution of vegetation types to the soil microbial community variation was 12%.If the indirect contribution through soil organic carbon was included,variations in the vegetation type had substantial influences on soil microbial composition and diversity.展开更多
To compare current methods of pretreatment/determination for plant foliar pH,we proposed a method for longperiod sample preservation with little interference with the stability of foliar pH.Four hundred leaf samples f...To compare current methods of pretreatment/determination for plant foliar pH,we proposed a method for longperiod sample preservation with little interference with the stability of foliar pH.Four hundred leaf samples from 20 species were collected and four methods of pH determination were used:refrigerated(stored at 4°C for 4 days),frozen(stored at−16°C for 4 days),oven-dried and fresh green-leaf pH(control).To explore the effects of different leaf:water mixing ratio on the pH determination results,we measured oven-dried green-leaf pH by leaf:water volume ratio of 1:8 and mass ratio of 1:10,and measured frozen senesced-leaf pH by mass ratio of 1:10 and 1:15.The standard major axis regression was used to analyze the relationship and the conversion equation between the measured pH with different methods.Foliar pH of refrigerated and frozen green leaves did not signifcantly differ from that of fresh green-leaf,but drying always overrated fresh green-leaf pH.During the feld sampling,cryopreservation with a portable refrigerator was an advisable choice to get a precise pH.For long-duration feld sampling,freezing was the optimal choice,and refrigeration is the best choice for the shorttime preservation.The different leaf:water mixing ratio signifcantly infuenced the measured foliar pH.High dilution reduced the proton concentration and increased the measured pH.Our fndings provide the conversion relationships between the existing pretreatment and measurement methods,and establish a connection among pH determined by different methods.Our study can facilitate foliar pH measurement,thus contributing to understanding of this interesting plant functional trait.展开更多
文摘The Tunisian coastal oases constitute a model of very rich plant biodiversity, organized in different floors of cultivation. The date palm is the highest, the second is the diversified fruit trees and the smallest is composed by various other productions. The present paper is the results of a RAA diagnosis and bibliographic analysis of nearly thirty years of work on oases. The aim of this study is to focus on the plant diversity and the traditions in using different products. The survey revealed the existence of nearly 45 local date palm varieties, about 26 fruit trees, 65 vegetables and divers other species. It also raises nearly 30 uses of dates and date palm by-products. This survey shows also that oases inhabitants keep in possessing, for a long time, a knowledge to make ingenious concerning use and conservation of the products and by products of the date palm. This survey has all as much demonstrated the risks from weakening this balance which has long been maintained. Some recommendations to maintain and conserve this system are also presented in this paper.
文摘Through analysis of the historical and present development of botanical gardens, both domestic and international, with particular focus on botanical garden practices within the Chinese Academy of Sciences (CAS), the authors propose that science-based botanical gardens (which differ from common public gardens), should be founded on plant diversity inventory and ex-situ conservation of wild plant species. Efforts should be directed to rarer species from biodiversity-rich areas and biodiversity hotspots, utilizing cutting-edge technologies to effectively preserve germplasm in living collections. Science-based botanical garden management should be directed by sound scientific evaluation of plant resources and guaranteed by innovative operational mechanisms. Science-based botanical gardens should also emphasize the establishment of identifiable and specialized living collections, research platforms and recruitment of qualified experts. In addition to curating living specimens, science-based botanical gardens should pursue research and development of new plant varieties or patents based on their plant collections, thus providing continual support to bio-industry.
文摘Mint is a medicinal and aromatic plant. It is very important for the pharmacopoeia, perfumes, confectionery and liquor industry. Some green mint leaves without rods are used as samples. Physical and mechanical properties of the sample such as the desorption isotherms, the density and volumetric withdrawal are determined. The kinetics of drying, where it follows the changes of the water content of the sample as a function of the drying time for the three temperatures 30, 40 and 50℃, is also presented and discussed.
基金supported by the National Natural Science Foundation of China (30700639,31170581)
文摘This study investigated the influence of broadleaf and conifer vegetation on soil microbial communities in a distinct vertical distribution belt in Northeast China.Soil samples were taken at 0-5,5-10 and 10-20 cm depths from four vegetation types at different altitudes,which were characterized by poplar(Populus davidiana)(1250-1300 m),poplar(P.davidiana) mixed with birch(Betula platyphylla)(1370-1550 m),birch(B.platyphylla)(1550-1720 m),and larch(Larix principis-rupprechtii)(1840-1890 m).Microbial biomass and community structure were determined using the fumigation-extraction method and phospholipid fatty acid(PLFA) analysis,and soil fungal community level physiological profiles(CLPP) were characterized using Biolog FF Microplates.It was found that soil properties,especially soil organic carbon and water content,contributed significantly to the variations in soil microbes.With increasing soil depth,the soil microbial biomass,fungal biomass,and fungal catabolic ability diminished;however,the ratio of fungi to bacteria increased.The fungal ratio was higher under larch forests compared to that under poplar,birch,and their mixed forests,although the soil microbial biomass was lower.The direct contribution of vegetation types to the soil microbial community variation was 12%.If the indirect contribution through soil organic carbon was included,variations in the vegetation type had substantial influences on soil microbial composition and diversity.
基金supported by the‘Strategic Priority Research Program’of the Chinese Academy of Sciences(XDA26040202)the National Natural Science Foundation of China(32001165)supported by Chinese Universities Scientifc Fund(2021TC117).
文摘To compare current methods of pretreatment/determination for plant foliar pH,we proposed a method for longperiod sample preservation with little interference with the stability of foliar pH.Four hundred leaf samples from 20 species were collected and four methods of pH determination were used:refrigerated(stored at 4°C for 4 days),frozen(stored at−16°C for 4 days),oven-dried and fresh green-leaf pH(control).To explore the effects of different leaf:water mixing ratio on the pH determination results,we measured oven-dried green-leaf pH by leaf:water volume ratio of 1:8 and mass ratio of 1:10,and measured frozen senesced-leaf pH by mass ratio of 1:10 and 1:15.The standard major axis regression was used to analyze the relationship and the conversion equation between the measured pH with different methods.Foliar pH of refrigerated and frozen green leaves did not signifcantly differ from that of fresh green-leaf,but drying always overrated fresh green-leaf pH.During the feld sampling,cryopreservation with a portable refrigerator was an advisable choice to get a precise pH.For long-duration feld sampling,freezing was the optimal choice,and refrigeration is the best choice for the shorttime preservation.The different leaf:water mixing ratio signifcantly infuenced the measured foliar pH.High dilution reduced the proton concentration and increased the measured pH.Our fndings provide the conversion relationships between the existing pretreatment and measurement methods,and establish a connection among pH determined by different methods.Our study can facilitate foliar pH measurement,thus contributing to understanding of this interesting plant functional trait.
