scholarly journals Heavy Grazing Altered the Biodiversity–Productivity Relationship of Alpine Grasslands in Lhasa River Valley, Tibet

2021 ◽  
Vol 9 ◽  
Author(s):  
Mingxue Xiang ◽  
Junxi Wu ◽  
Jiaojiao Wu ◽  
Yingjie Guo ◽  
Duo Lha ◽  
...  
Keyword(s):  
Soil Nutrients ◽  
Wiener Index ◽  
Diversity Indices ◽  
Alpine Grassland ◽  
Alpine Grasslands ◽  
Grazing Exclusion ◽  
Heavy Grazing ◽  
Lhasa River ◽  
Central Tibet ◽  
The Relationship

Grazing is a crucial anthropogenic disturbance on grasslands. However, it is unknown how livestock grazing affects the relationship between biodiversity and productivity of alpine grasslands in Tibet. We carried out a grazing-manipulated experiment from 2016 to 2019 with grazing intensity levels of null (control, grazing exclusion, C.K.), moderate grazing [1.65 standardized sheep unit (SSU) per hectare, M.G.], and heavy grazing (2.47 SSU per hectare, H.G.) on a typical alpine grassland in the Lhasa River Basin, central Tibet. We measured aboveground biomass (AGB), species assembly (alpha and beta diversity indices), and soil nutrients’ availability. The results showed that grazing differently affected plant community in different treatments. Notably, the total dissimilarity value between C.K. and H.G. is 0.334. Grazing decreased the Shannon–Wiener index, increased the Berger–Parker index from 2016 to 2018 significantly, and decreased AGB and total soil nitrogen (STN) significantly. Our results also showed that the grazing affected the relationship between AGB and diversity indices and soil nutrients, including soil organic carbon (SOC) and total soil phosphorus (STP). Specifically, AGB decreased with increasing SOC and STP in all treatments, and heavy grazing changed the positive relationships between AGB, STP, and Shannon–Wiener index to negative correlations significantly compared with grazing exclusion. There was a significant negative correlation between Berger–Parker and Shannon–Wiener indices under each treatment. The general linear models showed that H.G. altered the relationship between diversity and productivity of grassland in central Tibet, and AGB and Shannon–Wiener index positively correlated in C.K. but negatively correlated in H.G. Our study suggests that H.G. caused a negative relationship between plant diversity and productivity. Therefore, sustainable grazing management calls for a need of better understanding the relationship between biodiversity and productivity of alpine grassland in central Tibet.

scholarly journals Is grazing exclusion effective in restoring vegetation in degraded alpine grasslands in Tibet, China?

2015 ◽  
Author(s):  
Yan Yan ◽  
Xuyang Lu
Keyword(s):  
Management Strategy ◽  
Diversity Index ◽  
Alpine Grassland ◽  
Alpine Grasslands ◽  
Biodiversity Indicators ◽  
Effective Measure ◽  
Grazing Exclusion ◽  
Vegetation Height ◽  
Wiener Diversity Index ◽  
Grassland Type

Overgrazing is considered one of the key disturbance factors that results in alpine grassland degradation in Tibet. Grazing exclusion by fencing has been widely used as an approach to restore degraded grassland s in Tibet since 2004. Is the grazing exclusion management strategy effective for the vegetation restoration of degraded alpine grasslands? Three alpine grassland types were selected in Tibet to investigate the effect of grazing exclusion on plant community structure and biomass. Our results showed that species biodiversity indicators, including the Pielou evenness index, the Shannon-Wiener diversity index, and the Simpson dominance index, did not significantly change under grazing exclusion conditions. In contrast, the total vegetation cover, the mean vegetation height of the community, and the aboveground biomass were significantly higher in the grazing exclusion grasslands than in the free grazed grasslands. These results indicated that grazing exclusion is an effective measure for maintaining community stability and improving aboveground vegetation growth in alpine grasslands. However, the statistical analysis showed that the alpine grassland type plays a more important role than grazing exclusion in which influence on vegetation in alpine grasslands because the alpine grassland type had a significant effect on vegetation indicators but grazing exclusion not. In addition, because the results of the present study come from short term (5-7 years) grazing exclusion, it is still uncertain whether these improvements will be continuable if grazing exclusion is continuously implemented. Therefore, the assessments of the ecological effects of the grazing exclusion management strategy on degraded alpine grasslands in Tibet are still need long term continued research.

scholarly journals RECENT CHANGES IN THE ALPINE GRASSLANDS OF THE WEST COAST

1981 ◽  
pp. 210-212
Author(s):  
G.R. Evans
Keyword(s):  
West Coast ◽  
Full Range ◽  
Initial Response ◽  
Grazing Pressure ◽  
Alpine Grassland ◽  
Wild Animals ◽  
Alpine Grasslands ◽  
The West ◽  
Heavy Grazing ◽  
Full Stature

A full range of both tall and short snowgrass communities are present within the alpine grassland region of the West Coast; Many of the intertussock, fleshy herbs were removed with the initial grazing by wild animals, while the stature of many of the tall tussock communities was reduced with continual heavy grazing. Once major animal control operations were undertaken, a dramatic recovery in stature was recorded on the most favourable sites. This initial response could be very rapid as the tussocks required only a reduction in grazing pressure to attain their full stature.

scholarly journals Is grazing exclusion effective in restoring vegetation in degraded alpine grasslands in Tibet, China?

2015 ◽  
Author(s):  
Yan Yan ◽  
Xuyang Lu
Keyword(s):  
Management Strategy ◽  
Diversity Index ◽  
Alpine Grassland ◽  
Alpine Grasslands ◽  
Biodiversity Indicators ◽  
Effective Measure ◽  
Grazing Exclusion ◽  
Vegetation Height ◽  
Wiener Diversity Index ◽  
Grassland Type

Overgrazing is considered one of the key disturbance factors that results in alpine grassland degradation in Tibet. Grazing exclusion by fencing has been widely used as an approach to restore degraded grassland s in Tibet since 2004. Is the grazing exclusion management strategy effective for the vegetation restoration of degraded alpine grasslands? Three alpine grassland types were selected in Tibet to investigate the effect of grazing exclusion on plant community structure and biomass. Our results showed that species biodiversity indicators, including the Pielou evenness index, the Shannon-Wiener diversity index, and the Simpson dominance index, did not significantly change under grazing exclusion conditions. In contrast, the total vegetation cover, the mean vegetation height of the community, and the aboveground biomass were significantly higher in the grazing exclusion grasslands than in the free grazed grasslands. These results indicated that grazing exclusion is an effective measure for maintaining community stability and improving aboveground vegetation growth in alpine grasslands. However, the statistical analysis showed that the alpine grassland type plays a more important role than grazing exclusion in which influence on vegetation in alpine grasslands because the alpine grassland type had a significant effect on vegetation indicators but grazing exclusion not. In addition, because the results of the present study come from short term (5-7 years) grazing exclusion, it is still uncertain whether these improvements will be continuable if grazing exclusion is continuously implemented. Therefore, the assessments of the ecological effects of the grazing exclusion management strategy on degraded alpine grasslands in Tibet are still need long term continued research.

scholarly journals EVALUASI TERHADAP PERUBAHAN STATUS BEBERAPA HARA TANAH SETELAH 10 TAHUN DI BUKIT GAJABUIH PADANG

Jurnal Solum ◽  
2008 ◽  
Vol 5 (1) ◽  
pp. 23
Author(s):  
Hermansah Hermansah ◽  
Juniarti Juniarti ◽  
Utami Maya Pribadi
Keyword(s):  
Soil Nutrients ◽  
Rain Forest ◽  
Tropical Rain Forest ◽  
Soil Nutrient ◽  
Nutrient Status ◽  
The Other ◽  
Experimental Plot ◽  
Soil Nutrient Status ◽  
P Content ◽  
The Relationship

This experiment is about the evaluation of characteristic alteration of soil nutrients after ten years at tropical rain forest Bukit Gajabuih Gunung Gadut Padang. This experiment was conducted from November 2006 - April 2007.  This experiment is arranged based on anova design with three treatments which was based on three great groups of land ( oxic-dystroudept (eutriccc, aquic), oxic-dystroudept (xanthic), oxic-typic-dystroudept (xanthic)).  The purpose of this experiment was to study the alteration of soil fertility characteristics  (K, Ca, Mg, Na, P and C/N) in ten years period (1995-2005) in tropical rain forest at Bukit Gajabuih Padang, to observe vegetation variety alteration, and the relationship with the land fertility characteristics.  From the experiment was found that nutrient status of the soils altered after ten years (*1995-2005).  Available P content increased about 77%, exchangeable Na and K  increased 86,04% and 53.65%, respectively.  On the other hand, exchangeable Mg and Ca decreased 3,05% and 65,88%, respectively.  Land C/N ratio decreased about 21,39%. The experimental plot had low soil pH.Key Words: tropical rain forest, soil nutrient status

scholarly journals Interaction between root exudates and rhizosphere microorganisms facilitates the expansion of poisonous plant species in degraded grassland

2021 ◽  
Author(s):  
Wenyin Wang ◽  
Tianhua Jia ◽  
Tianyun Qi ◽  
Shanshan Li ◽  
Degen A.Allan ◽  
...  
Keyword(s):  
Plant Species ◽  
Soil Nutrients ◽  
Root Exudates ◽  
Carbon Metabolism ◽  
Soil Microbial Communities ◽  
Alpine Grassland ◽  
Poisonous Plant ◽  
Poisonous Plants ◽  
Rhizosphere Microorganisms ◽  
Degraded Grassland

Abstract Background The interaction between rhizosphere microorganisms and rhizosphere exudates is considered a ‘novel weapon’ for poisonous plants’ colonization, but the relationship between them in facilitating the expansion of poisonous plants in degraded or barren land is poorly understood. We examined this relationship in different degradation levels of alpine grasslands on the Tibetan plateau (3,700 m a.s.l) by determining the composition of root exudates, soil physical and chemical properties, rhizosphere microbial diversity and carbon metabolism of the main poisonous and non-poisonous plant species. Results Soil nutrients, including total organic carbon, total nitrogen and available phosphorous, diversity of microorganisms and microbial carbon metabolism were greater in the rhizosphere of poisonous than in non-poisonous plant species (P < 0.05). The distribution of bacteria and root exudates were plant species specific. Soil microbial communities were affected by habitat and plant species in degraded grassland, and more so for bacteria than fungi. The cell growth and death pathway for the poisonous species Ligularia virgaurea was greater than for other poisonous species (P < 0.05), and the difference increased with an increase in grassland degradation and a decrease in soil nutrients (P < 0.05), which could explain how L. virgaurea became the dominant poisonous species in degraded alpine grassland. The roots of L. virgaurea exudated such compounds as alkaloids, lupinic acid, terpenes, artemisinin, and coumarin, which were correlated positively with different bacteria in different habitats. Conclusion It was concluded that poisonous plant species adapted to degraded grassland through the interaction of root exudates and rhizosphere microorganisms, which facilitated their expansion in degraded alpine grassland.

scholarly journals COMPARATIVE STUDY OF MYCOFLORA, ANTIBACTERIAL ACTIVITY AND PHYTOCHEMISTRY OF SELECTED FRESH AND STORED MEDICINAL FRUITS

2017 ◽  
Vol 9 (10) ◽  
pp. 43
Author(s):  
Sushma K. S. ◽  
Puttaswamy Rajeshwari ◽  
Koteshwar Anandrao Raveesha
Keyword(s):  
Diversity Index ◽  
Wiener Index ◽  
Diversity Indices ◽  
Dilution Method ◽  
Phytochemical Analysis ◽  
Fungal Contamination ◽  
Terminalia Bellerica ◽  
Significant Difference ◽  
Proper Training ◽  
Antibacterial Potential

Objective: To understand the mycoflora, phytochemical constituents and antibacterial potential of fresh and stored herbal fruits of selected plants, extensively used in herbal medicines.Methods: Mycoflora analysis of Terminalia bellerica, Phyllanthus emblica and Myristica fragrans fruits was done employing serial dilution method, colony forming unit (CFU) and relative density of each fungi was recorded. The diversity of fungi associated with test fruits was calculated using various diversity indices. Methanol extracts of test fruits was subjected to preliminary phytochemical analysis, presence or absence of alkaloids, flavonoids, tannins, saponins, terpenoids, quinones and cardiac glycosides was detected. Antibacterial potential of test fruits was studied by well diffusion method.Results: Fresh fruits were free of fungal contamination, whereas stored fruits were found in association with various fungi. A total of 64 isolates of 29 species belonging to 13 genera were identified from stored fruits. Aspergillus was predominant followed by Penicillium. T. bellerica was highly contaminated (1x105CFU/g). Stored fruits of M. fragrans recorded high fungal diversity with highest Simpson’s diversity index (D-1=0.840) and Shannon-Wiener index (H=2.888). P. emblica exhibited high species richness with high Margalef Richness (R=2.925), Menhinick index (E=1.830) and Berger Parker Dominance (d’=0.418). Phytochemical analysis of fresh and stored fruits did not show a significant difference in the presence or absence of tested phyto-constituents. Stored fruit extract recorded up to 41% increase in antibacterial activity.Conclusion: Results suggests the need of proper training to the herbal material handler’s right from the harvest to retail selling, and also points out the need to assess the fungal contamination of herbal materials before using them for herbal drug manufacture.

Relationship Between the Distribution and Biodiversity of Sand Flies (Diptera: Psychodidae) With the Incidence of Zoonotic Cutaneous Leishmaniasis in Endemic Foci of Golestan Province, Iran

2020 ◽  
Vol 57 (6) ◽  
pp. 1768-1774
Author(s):  
Aioub Sofizadeh ◽  
Kamran Akbarzadeh ◽  
Ehsan Allah Kalteh ◽  
Fatemeh Karimi
Keyword(s):  
Cutaneous Leishmaniasis ◽  
Diversity Index ◽  
Wiener Index ◽  
Sand Flies ◽  
Phlebotomus Papatasi ◽  
Light Traps ◽  
Phlebotomine Sand Flies ◽  
Zoonotic Cutaneous Leishmaniasis ◽  
Golestan Province ◽  
The Relationship

Abstract Zoonotic cutaneous leishmaniasis (ZCL) is prevalent in Golestan Province, Iran. The current study determined the relationship between the distribution and biodiversity of sand flies with cutaneous leishmaniasis at 14 villages in plain and hillsides areas. In each village from July to September 2017, 60 sticky traps and 2 CDC light traps were laid. Spearman and Mann–Whitney tests were used to determine the relationship between the incidence of ZCL and the abundance of different species of sand flies. Simpson, Shannon-Wiener, Evenness, and Margalef indices were calculated to estimate the diversity of species. A total of 5,295 phlebotomine sand flies were collected, comprising 10 species of the genus Phlebotomus (3,947 flies) and 7 species of genus Sergentomyia (1,248 flies). The abundance of sand flies and incidence of ZCL in plain areas were greater than that of hillsides areas (P = 0.013, P = 0.002). There was a significant correlation between the incidence of ZCL and the abundance of Phlebotomus papatasi (r = 0.72, P = 0.004) and P. caucasicus groups (P = 0.006; 0.022). In the Shannon-Wiener index, the rest of the biodiversity indices were reduced in higher-altitude areas. Increasing Shannon-Wiener index showed higher diversity of sand flies in higher-altitude areas. Data of the reported cases of leishmaniasis in plain areas can reveal the relationship between less diversity index (Shannon-Wiener), higher dominant diversity index (Simpson), and incidence of leishmaniasis in these areas.

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