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PubMed | Yunnan Normal University, Research Institute of Plateau Ecology and CAS Institute of Botany
Type: | Journal: TheScientificWorldJournal | Year: 2015

Generally, plant reproductive success might be affected negatively by florivory, and the effects may vary depending on the timing and intensity of florivory. To clarify the impacts of florivory by the sawfly larvae (Tenthredinidae) on seed production of Halenia elliptica D. Don, we simulated florivory by removing different proportion of flowers at three reproductive stages in this alpine herb and then examined the seed number per fruit, the seed weight, and the seed mass per fruit of the remaining flowers. Seed number per fruit reduced significantly when flowers were removed at flowering and fruiting stages or when 15% and 60% of flowers were removed. However, seed weight increased significantly after flowers were removed, independent of treatments of reproductive stage and proportion. There was a similar seed mass per fruit between the plants subjected to simulation of florivory and control. The results indicated that florivory modulated the seed number-seed weight relationship in this alpine species. Our study suggested that selective seed abortion and resource reallocation within fruits may ensure fewer but larger seeds, which were expected to be adaptive in the harsh environments.


Ma H.-P.,Research Institute of Plateau Ecology | Guo Q.-Q.,Research Institute of Plateau Ecology | Liu H.-M.,Tibet Agricultural and Animal Husbandry College | Qian D.-F.,Tibet Agricultural and Animal Husbandry College
Forest Research | Year: 2013

In order to explore the effects of total nutrient on surface soil (0~20cm), the alpine shrub, Rhododendron forest, Abies georgei var. smithii forest and Picea likiangensis var. linzhiensis forest were selected as experimental sites, the soil organic carbon (SOC), total nitrogen (TN), microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), readily oxidizable organic carbon (ROC), and particulate organic carbon (POC) were studied at different altitudes. The results showed that compared with lower-elevation vegetation types, the higher ones were found significantly higher in their SOC content and proportion. The SOC and TN contents were increasing along the elevation gradient in Sejila Mountain. The surface SOC of alpine shrub was the largest (77.167) and P. likiangensis var. linzhiensis forest the smallest(22.351). The TN of alpine shrub was the largest(2.430) and P. likiangensis var. linzhiensis forest the smallest(0.830). The surface C/N ratio of A. georgei var. smithii forest was the largest(43.57) and P. likiangensis var. linzhiensis forest the smallest(26.93). The elevation and wood stand had a significant impact on MBC and MBN. With lower altitude, the ratio of the POC in TOC decreased from 44.81% to 19.32%, the ratio of ROC in TOC decreased from 41.72% to 7.07%. The POC and ROC of different wood lands were significantly related to SOC. And the active SOC was significantly related to total SOC. The relationship between soil microbial biomass and readily oxidizable organic carbon was significant(p < 0.05).


Meng L.-H.,Yunnan Normal University | Wang Y.,CAS Kunming Institute of Botany | Luo J.,Research Institute of Plateau Ecology | Yang Y.-P.,CAS Kunming Institute of Botany | Duan Y.-W.,CAS Kunming Institute of Botany
Polish Journal of Ecology | Year: 2014

Given the finite resources of seed production, a trade-off between seed weight and number was expected. However, it still remains unclear how the seed weight-number trade-off changes if there are some mechanisms to enhance resource acquirements during the fruit developments. Sinopodophyllum hexandrum presents furled leaves in flowering time but unfurled leaves in fruiting time, which is considered to enhance the photosynthates to fruit development. To determine the relationship between seed weight and number of S. hexandrum, we examined the altitudinal variations and the relationship between seed weight and number in the fruits from 27 populations of in 2009 and 2010. Our results showed that, along the altitudinal gradient, seed weight decreased significantly but seed number increased insignificantly, indicating that the selective pressure on seed production might come from seed dispersal in high altitude populations. There was no significant relationship between seed weight and number in most populations, but an inverse relationship was found between seed weight and number when the data from all populations were pooled, indicating the seed weight-number trade-off and resource limitation of seed production in S. hexandrum on species level. We suggested that the two unfurled leaves of S. hexandrum might contribute to the resources allocated to the fruit development via enhancing photosynthates, which might mask the seed weight-number trade-off on population level to some degree. © 2014, Polish Academy of Sciences. All rights reserved.


Meng L.-H.,Yunnan Normal University | Wang Y.,CAS Kunming Institute of Botany | Luo J.,Research Institute of Plateau Ecology | Liu C.-Y.,Yunnan Normal University | And 2 more authors.
Plant Ecology and Evolution | Year: 2012

Background and aims - Megacodon stylophorus (C.B.Clarke) Harry Sm. is an endangered herb native to the East-Himalaya and the Hengduan Mountains, south-west China. We studied reproductive ecology of this species to explore the factors that are critical for its survival and conservation. Methods - We conducted breeding system experiments during 2008 and 2009 in two populations located in the Hengduan Mountains. Key results - The flowers are protandrous and herkogamous, and thus insects are necessary for pollination and seed production. Bumblebees were observed to be the most frequent visitors, and their visitation rates were lower at the higher altitude. Seed production in both populations fluctuated annually, possibly due to pollen limitation, which occurred in both populations in the two years. Conclusions - The pollination level is only marginally responsible for the rarity of this alpine species. We suggest that in situ conservation measures should be given the highest priority at present, considering the strong genetic differentiation among populations. © 2012 National Botanic Garden of Belgium and Royal Botanical Society of Belgium.


Wang L.,CAS Kunming Institute of Botany | Meng L.,Yunnan Normal University | Luo J.,Research Institute of Plateau Ecology
Scientific World Journal | Year: 2015

Generally, plant reproductive success might be affected negatively by florivory, and the effects may vary depending on the timing and intensity of florivory. To clarify the impacts of florivory by the sawfly larvae (Tenthredinidae) on seed production of Halenia elliptica D. Don, we simulated florivory by removing different proportion of flowers at three reproductive stages in this alpine herb and then examined the seed number per fruit, the seed weight, and the seed mass per fruit of the remaining flowers. Seed number per fruit reduced significantly when flowers were removed at flowering and fruiting stages or when 15% and 60% of flowers were removed. However, seed weight increased significantly after flowers were removed, independent of treatments of reproductive stage and proportion. There was a similar seed mass per fruit between the plants subjected to simulation of florivory and control. The results indicated that florivory modulated the seed number-seed weight relationship in this alpine species. Our study suggested that selective seed abortion and resource reallocation within fruits may ensure fewer but larger seeds, which were expected to be adaptive in the harsh environments. © 2015 Linlin Wang et al.


Ma Q.-G.,Chinese Academy of Forestry | Wang H.,Chinese Academy of Forestry | Wang H.,Huazhong Agricultural University | Pan G.,Research Institute of Plateau Ecology | Pei D.,Chinese Academy of Forestry
Beijing Linye Daxue Xuebao/Journal of Beijing Forestry University | Year: 2011

In order to deeply understand the genetic background and the genetic diversity of Tibet walnut germplasm resources, FISH-AFLP was conducted using 9 EcoR I+3/Mse I+3 primer combinations to analyse 11 walnut (Juglans regia L.) advanced trees from Tibet at genomic DNA level. Totally 1103 AFLP fragments were obtained, in which 1076 were polymorphic and the average percentage of polymorphic bands (ppb) was 97.67%. The value of effective number of alleles (Ne) ranged from 1.00 to 1.99 with an average of 1.48 ± 0.04; Nei's gene diversity (H) ranged from 0.00 to 0.49 with an average of 0.29 ± 0.02 and Shannon's information index (I) ranged from 0.00 to 0.69 with an average of 0.44 ± 0.02. The genetic diversity and sibship among walnut advanced trees in Tibet were investigated and their fingerprintings were established in the research.


Ma H.-P.,Research Institute of Plateau Ecology | Yang X.-L.,Tibet Agriculture and Animal Husbandry College | Guo Q.-Q.,Research Institute of Plateau Ecology | Zhang X.-J.,Research Institute of Plateau Ecology | Zhou C.-N.,Research Institute of Plateau Ecology
Journal of Mountain Science | Year: 2016

Labile organic carbon (LOC) is one of the most important indicators of soil organic matter quality and dynamics elevation and plays important function in the Tibetan Plateau climate. However, it is unknown what the sources and causes of LOC contamination are. In this study, soil organic carbon (SOC), total nitrogen (TN), microbial biomass carbon (MBC), microbial biomass nitrogen (MBN) and LOC were analyzed based on different soil horizons and elevations using turnover time in an experimental site (3700 m to 4300 m area) in Sygera. SOC and LOC in higher-elevation vegetation types were higher than that of in lower-elevation vegetation types. Our results presented that the soil microbial biomass carbon (SMBC) and soil microbial biomass nitrogen (SMBN) were positively correlated with SOC. The content of easily oxidized carbon (EOC), particulate organic carbon (POC) and light fraction organic carbon (LFOC) decreased with depth increasing and the content were the lowest in the 60 cm to 100 cm depth. The total SOC, ROC and POC contents decreased with increasing soil horizons. The SOC, TN, MBC and MBN contents increased with increasing altitude in the Sygera Mountains. The MBC and MBN contents were different with the changes of SOC (p<0.05), meanwhile, both LFOC and POC were related to total SOC (p<0.05). The physical and chemical properties of soil, including temperature, humidity, and altitude, were involved in the regulation of SOC, TN, MBC, MBN and LFOC contents in the Sygera Mountains, Tibetan Plateau. © 2016, Science Press, Institute of Mountain Hazards and Environment, CAS and Springer-Verlag Berlin Heidelberg.


Zhou C.,Research Institute of Plateau Ecology | Ren D.,Research Institute of Plateau Ecology | Ma H.,Research Institute of Plateau Ecology | Guo Q.,Research Institute of Plateau Ecology
Huanjing Kexue Xuebao/Acta Scientiae Circumstantiae | Year: 2015

Soil active organic carbon and soil respiration and its components is the key problem in forest soil carbon cycle process. The virgin forest in Tibetan Plateau is an important ecological barrier of China, which plays a decisive role in global terrestrial ecosystem carbon balance. In this study, the two most typical natural forests in Segara Mountain (Abies georgei var. smithii and Picea likiangensis var. linzhiensis) were selected as the objects, the content of active organic soil carbon and the corresponding soil respiration of these forests were measured, and the relationship between the active organic soil carbon components and soil respiration was analyzed as well. The results showed that: (1)The content of TOC, POC, ROC and MBC of these two forests showed significant surface accumulation. The content of active organic carbon of Abies georgei var. smithii was higher, contents of its TOC, POC, ROC and MBC were 57.05 g·kg-1, 17.9 g·kg-1, 12.2 g·kg-1 and 365.6 mg·kg-1, respectively. (2)Rt and Rh between these two forests did not present significant differences (p>0.05), but significant differences were presented in Rl and Rr (p<0.01). At the same time, significant difference was presented between Rl and Rr (p<0.01). Based on the results of the two different forests, Picea likiangensis var. linzhiensis showed higher Rt and Rh, whereas Abies georgei var. smithii showed higher Rl and Rr. The descending order of the contribution rate of the soil respiration components was: Rh> Rl> Rr. The contribution rates of Rh to Rt of these two forests were the highest (92.42% in Picea likiangensis var. linzhiensis and 70.81% in Abies georgei var. smithii). (3)The closest relationship between active organic soil carbon and soil respiration was found for MBC, and followed by ROC and POC. ©, 2015, Science Press. All right reserved.


Luo D.-Q.,Research Institute of Plateau Ecology | Zhang X.-J.,Research Institute of Plateau Ecology | Ren D.-Z.,Research Institute of Plateau Ecology
Beijing Linye Daxue Xuebao/Journal of Beijing Forestry University | Year: 2014

Through the microclimate observation of gaps and non-gaps (under-canopy and open spaces) of Abies georgei forest in the Sejila Mountain, southeastern Tibet, we monitored daytime total radiation, air temperature, relative humidity, surface temperature and 5-15 cm layer soil temperature, and analyzed the similarities and differences of microclimate between forest gaps and non-gaps in summer time. The results showed that, the annual change of total solar radiation to fir gaps presented bimodal curve and the peak values appeared in May and August. The diurnal and annual variation ranges of total solar radiation in forest gaps were less than that of open spaces, and meanwhile, the annual total solar radiation of gaps was 1173.28 MJ/m2, which was significantly lower than that of the open spaces (P < 0.01). The changing curves of air temperature in gaps and non-gaps during summer daytime were of inverted S, and the diurnal variation range of air temperature in gaps was small, ranging between open spaces and under- canopy, and it was closed to that in under-canopy and significantly lower than that in the open spaces. The relative humidity of gaps was higher than that of open spaces and under-canopy, meanwhile the variation range of it was small. The diurnal variation trend of surface temperature in forest gaps and non- gap was basically consistent with the change of air temperature. The temperatures of land surface and soil layers in open spaces were significantly higher than that in gaps and under-canopy. The soil temperature decreased with the increase of soil depth, and there was no obvious diurnal variation under 10 cm layer. Due to the influence of solar radiation to the surface temperature, the diurnal variation amplitude of it was much higher than that of the soil temperature. ©, 2014, Beijing Forestry University. All right reserved.


Ma H.,Research Institute of Plateau Ecology | Guo Q.,Research Institute of Plateau Ecology | Liu H.,Tibet Agriculture and Animal Husbandry College | Qian D.,Tibet Agriculture and Animal Husbandry College
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2013

AS a key component of ecosystem carbon budgets, soil carbon is the largest carbon pool of forest ecosystem. Soil microbial biomass carbon is an important component of carbon cycle of the terrestrial ecosystem. In order to explore the effects of different forest types on soil active carbon pool, we chosed Alpine Shrub AS,Rhododendron Forest RF,Abies georgei var. smithii forest AGSF and Picea likiangensis var. linzhiensis forest PLLF as experimental sites in the Sygera Mountainous southeast Tibet. Soil organic carbon SOC, total nitrogen TN and soil microbial biomass were studied at different soil horizon. There is higher LOC(labile organic carbon) at higher-elevation vegetation types in comparison with lower-elevation ones. At 0-10cm soil layer, SOC among the AS, RF, AGST and PLLF were significantly different P< 0.05. However, no trend was found for SOC at 10-20cm and 20-40cm. At the AS site, TN were significantly different at 0-10cm soil layer P<0. 05. There were no significant difference for the AS, RF, AGST and PLLF sites P<0. 05. At 10-20cm soil layer, there were significant difference for them(P<0. 05). However, no regularity was found for SOC at 20-40cm. At different depths, the soil microbial biomass was significantly correlated to soil organic carbon. The SMBC and SMBN was positively correlated with SOC, and the SMBN or its ratio was also positively correlated with the SMBC content and its ratio. The SMBC and SMBN increase with increasing elevationt in the Sygera Mountains. As shown, the total SOC, readily oxidizable carbon and particulate organic carbon decreased with increasing soil horizons. The rations of particulate organic carbon to total SOC content and the readily oxidizable carbon to total SOC content were different in their range. Moreover, their ratios decreased with increasing soil horizons. The active SOC was significantly related to total SOC. In addition, the relationship between readily oxidizable carbon and particulate organic carbon was also significant P<0. 05.

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