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Infl uence of the slope aspect on the ectomycorrhizal fungal community of Quercus variabilis Blume in the middle part of the Taihang Mountains,North China

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Journal of Forestry Research 2021年第1期32卷 385-400页

作者： Songpo Wei Yijing Song Liming Jia College of Forestry Beijing Forestry UniversityBeijing 100083People’s Republic of China

The slope aspect is one of the most critical topographic factors in mountainous *** is known,however,about the eff ect of the aspect on the ectomycorrhizal(ECM)fungal ***,we know very little about the composition of ECM fungal communities associated with Quercus variabilis,which is widely distributed in East *** this study,we compared the richness,community composition,and exploration types of ECM fungi associated with *** between predominantly south-and north-facing slopes in the Taihang Mountain,North China for the fi rst *** was extracted from the root tips of ***,and Illumina MiSeq sequencing was used to identify ECM *** total,168 operational taxonomic units belonging to 28 genera were detected,and the ECM community was found to be dominated by Russula,Inocybe,Tomentella,Scleroderma,and *** with the north-facing slopes,the ECM communities on the south-facing slopes had higher *** community composition and exploration types were directly aff ected by the slope ***,the aspect-induced edaphic variables,such as total phosphorus,total nitrogen,total potassium,pH,and soil water content,were important sources of variation in ECM fungal richness and distributions of exploration *** erent genera tended to be distributed in various slope ***,Genea,and Clavulina were signifi cantly enriched in north-facing slopes,while Geopora,Helvelosebacina,Scleroderma,Gyroporus,Astraeus,Boletus,Tricholoma,Hebeloma,Cortinarius and unclassifi ed Thelephoraceae were more abundant in south-facing *** ECM fungi were obviously enriched in the south-facing slope,but there was no statistical diff erence between hydrophilic among the south-and north-facing *** study deepened our knowledge of the aspect-driven variation in ECM fungal communities associated with ***.

关键词： Ectomycorrhizal community Illumina sequencing Quercus variabilis slope aspect Edaphic factors

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Effects of drought and slope aspect on canopy facilitation in a mountainous rangeland

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Journal of Plant Ecology 2017年第4期10卷 626-633页

作者： Mohammad Farzam Hamid Ejtehadi Department of Range and Watershed Management Faculty of Natural Resources and EnvironmentFerdowsi University of MashhadMashhadIran Department of Biology Faculty of SciencesFerdowsi University of MashhadMashhadIran

Aims Species composition and diversity of the mountainous rangelands are results of interactions between environmental severities,het-erogeneous topography and facilitative effects by nurse *** research was aimed to compare relative effects of these three envi-ronmental variables on the natural vegetation of a mountainous *** a more detailed understanding,effects of four dif-ferent nurse species were separately compared on the various plant growth forms and on two community plant responses(diversity and abundance).Methods A mountainous semiarid rangeland was selected in Baharkish,Quchan,Northeast of *** and canopy cover of all plant species were recorded under the canopy of four different shrubs and in open areas,in north and south-facing aspects,and in a normal and a drought *** diversity,total abundance(%cover)and the abundance of different growth forms were used as crite-ria for assessing effects of the environmental *** were arranged in a factorial combination and analyzed by three-way analysis of variance using a GLM *** Findings(i)Drought,aspect and canopy created niche differentiation:annual forbs and shrubs were more affected by drought,whereas geophytes and grasses were more responsive to slope *** of drought and slope aspect were more profound on species diversity,whereas that of canopy facilitation was stronger on plant abundance.(ii)Canopy facili-tation was dependent on severity of the abiotic factors and life history of interacting *** facilitation allowed for the persistence of only annual forbs,but it was disadvantaged during the drought *** community responses to abiotic factors(slope and drought)were more dependent on the plant growth form,while responses to canopy facilitation were more dependent on the morphology and/or ecology of nurse shrubs.(iii)Effect of shrubs was dependent on their morphology and ecology:shrubs with larger canopy area and nitrogen fix

关键词： biotic interactions facilitation slope aspect plant ecology growth forms

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Changes in climatic conditions drive variations in arbuscular mycorrhizal fungi diversity and composition in semi-arid oak forests

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JOURNAL OF FORESTRY RESEARCH 2024年第1期35卷 1-14页

作者： Jafarian, Nahid Mirzaei, Javad Omidipour, Reza Kooch, Yahya Ilam Univ Fac Agr Dept Forest Sci Ilam 69315516 Iran Ilam Univ Fac Agr Dept Range & Watershed Management Ilam 69315516 Iran Tarbiat Modares Univ Fac Nat Resources & Marine Sci Noor *** Mazandaran Iran

Arbuscular mycorrhizal fungi (AMF) play a vital role in plant productivity and ecosystem functions. However, their responses to abiotic factors (i.e., climate, physiography, and soil properties) are unknown, especially across climatic gradients and slope aspects in arid and semi-arid ecosystems. In this study, using 60 composite soil samples, direct and indirect effects of climate factors and slope aspects on AMF diversity, composition and spore density were studied. The findings indicate that climate has a more direct influence on soil properties (P slope aspect (P = 0.449). In contrast, climate significantly affected AMF diversity and composition, with the highest diversity in dryer areas. Soil pH had the highest correlation with different facets of AMF diversity. Structural equation modeling (SEM) indicated that only a small part of the variation in AMF diversity and spore density could be explained by climate characteristics, slope aspect and soil properties. Based on SEM results, climate was the most important determinant of AMF diversity and spore density; slope aspect had a less critical role. The outputs suggest that variations in AMF diversity are derived by the direct effects of climate and the indirect effect of soil chemical properties. In addition, with increasing dryness, sporulation and AMF diversity increased.

关键词： AMF diversity and composition Physiographic factors Semi-arid ecosystems Zagros forest SOIL ORGANIC-MATTER slope aspect MICROBIAL BIOMASS NUTRIENT-UPTAKE COMMUNITIES PHOSPHORUS GRADIENT BIODIVERSITY RESPOND IMPACT

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Response of soil nutrients to terracing and environmental factors in the Loess Plateau of China

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Geography and Sustainability 2024年第2期5卷 230-240页

作者： Die Chen Wei Wei Liding Chen Bojun Ma Hao Li Department of Soil and Water Conservation Changjiang River Scientific Research InstituteWuhan 430010China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Research Center on Mountain Torrent&Geologic Disaster Prevention of Ministry of Water Resources Wuhan 430010China

Terracing is a widely adopted agricultural practice in mountainous regions around the world that aims to conserve soil and water *** nutrients play a crucial role in determining soil quality,particularly in landscapes prone to *** are influenced by factors such as land-use type,slope aspect,and *** this study,we sought to examine the impact of terracing on soil nutrients(soil organic content(SOC),total nitrogen(TN),nitrate-nitrogen(NO_(3)^(-)-N),ammonium nitrogen(NH_(4)^(+)-N),total phosphorus(TP),available phosphorus(AP),total potassium(TK),and available potassium(AK))and how they vary with environmental factors in the Chinese Loess *** the growing season,we collected 540 soil samples from the 0 to 100 cm soil layer across five major land-use types,different slope aspects,and varying ***,a meta-analysis of literature data further corroborated the effective accumulation of soil nutrients through terracing in the Loess *** findings are as follows:(1)Terraced fields,regardless of land-use type,showed a significant improvement in SOC and TN content.(2)Soil nutrient contents within terraced fields were predominantly higher on sunny slopes.(3)Terraces at lower altitudes are characterized by elevated SOC concentrations.(4)A meta-analysis of literature data pertaining to terracing and soil nutrients in this region confirmed the effective accumulation of soil nutri-ents through *** elucidated outcomes of this study offer a profound theoretical underpinning for the accurate planning and management of terraces,the scientific utilization of land resources,and the enhancement of land productivity.

关键词： Terrace Soil nutrients Land-use slope aspect Altitude Loess Plateau

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Forest recovery after clear-cutting in Chinese pine(Pinus tabuliformis) plantations of North China

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Journal of Arid Land 2018年第2期10卷 233-248页

作者： DONG Boqian ZHAO Kuangji WANG Zhibin JIA Zhongkui MA Lvyi XIA Xinli Key Laboratory for Silviculture and Conservation of the Ministry of Education College of Forestry Beijing Forestry University College of Biological Sciences and Technology Beijing Forestry University

In Hebei Province of North China, forest was recovered with natural recruitment in plantations with large area of clear-cutting Chinese pine（Pinus tabuliformis）. This study was aimed to demonstrate the dynamic characteristics of recruits during the natural recruitment. Both plot survey and the spatial point-pattern analysis were performed. Five developmental stages of natural recruitment were selected and studied, including 1 year before and 2, 5, 8, and 11 years after clear-cutting. Different slope aspects were also included. Natural recruitment was always dominated by Chinese pine with a proportion of higher than 90%. For plots of 1 year before clear-cutting on east-and north-facing slopes, recruit densities were 7886 and 5036 stems/hm2, the average heights were 0.78（±0.85） and 1.06（±1.15） m, and the average diameters at breast height（DBH） were 3.21（±1.38） and 2.91（±1.38） cm, respectively. After clear-cutting, recruit density was initially increased, then it was gradually declined with time; however, the variation of average DBH was contrary to that of recruit density. Both of them were no longer varied between 8 and 11 years after clear-cutting. The average height of recruits continued to increase after clear-cutting. For the plots of 11 years after clear-cutting on east-and north-facing slopes, average heights of recruits reached 2.00（±1.14） and 2.24（±1.20） m, respectively. The statuses of recruits on north-facing slopes were better than those on east-facing slopes after clear-cutting. Meanwhile, recruits on east-facing slopes were always aggregated at small scales, while spatial pattern of recruits varied with time on north-facing slopes. Moreover, forest was recovered more quickly by natural recruitment than by artificial afforestation after clear-cutting. The structural diversity was higher in naturally regenerated forests than in plantations of the same age. Our results demonstrated that clear-cutting of Chinese pine plantations recovered by natural recruitm

关键词： Chinese pine natural recruitment clear-cutting slope aspect spatial pattern Hebei Province

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The effect of low-temperature event on the survival and growth of Juglans mandshurica seedlings within forest gaps

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Journal of Forestry Research 2018年第4期29卷 939-947页

作者： Xiufen Li Yongjing Wen Jinxin Zhang Limin Liu Lei Jin Tao Yan Yi Wang Agronomy college Shenyang Agricultural University Qingyuan Forest CERN Chinese Academy of Sciences Institute of Applied Ecology Chinese Academy of Sciences

In forest ecosystems, gap formation changes the allocation of abiotic resources and thus affects the survival and growth of understory plants. However, how tree seedling survival and growth respond to low-temperature events and the influencing mechanisms remain unclear. To clarify how low-temperature event limits the survival and growth of tree seedlings in the montane regions of eastern Liaoning Province, northeast China, we investigated temperature and light intensity within secondary forest gaps, and the survival and growth of Juglans mandshurica seedlings after a low-temperature event in the spring of 2014. Damage to seedlings due to low temperature sig- nificantly varied in different aspects. Seedlings in gaps on southeast-facing slopes were the most seriously damaged, followed by those in gaps on northeast-facing slopes. In contrast, seedlings in west-facing gaps and in control plots without slope aspect were not damaged. The freezing injury index for seedlings was negatively correlated with minimum temperature （r = - 0.608, P 〈 0.01）, but it was positively correlated with light intensity （r= 0.818, P 〈 0.01）. In addition, height and root collar diameter of damaged seedlings were significantly lower than those of the undamaged seedlings （P 〈 0.01） during the early growing season （April-July）, but no significant difference were observed during the late growing season （July-Oc- tober）（P 〉 0.05）. The extent of seedling damage was directly related to slope aspect. Low temperature and high light intensity were found to be the dominant factors affecting extent of damage to seedlings on southeast- and northeast-facing slopes.

关键词： Secondary forest gap Freezing injury index Minimum temperature Light intensity slope aspect

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Effect of aspect on Climate Variation in Mountain Ranges of Shennongjia Massif, Central China

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Chinese Geographical Science 2018年第1期28卷 74-85页

作者： ZHANG Yi School of Earth Sciences China University of Geosciences The College of Urban & Environmental Sciences Central China Normal University

The aim of this study was to better understand the mechanisms of regional climate variation in mountain ranges with contrasting aspects as mediated by changes in global climate. It may help predict trends of vegetation variations in native ecosystems in natural reserves. As measures of climate response, temperature and precipitation data from the north, east, and south-facing mountain ranges of Shennongjia Massif in the coldest and hottest months(January and July), different seasons(spring, summer, autumn, and winter) and each year were analyzed from a long-term dataset(1960 to 2003) to tested variations characteristics, temporal and spatial quantitative relationships of climates. The results showed that the average seasonal temperatures and precipitation in the north, east, and south aspects of the mountain ranges changed at different rates. The average seasonal temperatures change rate ranges in the north, east, and south-facing mountain ranges were from –0.0210℃/yr to 0.0143℃/yr, –0.0166℃/yr to 0.0311℃/yr, and –0.0290 ℃/yr to 0.0084℃/yr, respectively, and seasonal precipitation variation magnitude were from –1.4940 mm/yr to 0.6217 mm/yr, –1.6833 mm/yr to 2.6182 mm/yr, and –0.8567 mm/yr to 1.4077 mm/yr, respectively. The climates variation trend among the three mountain ranges were different in magnitude and direction, showing a complicated change of the climates in mountain ranges and some inconsistency with general trends in global climate change. The climate variations were significantly different and positively correlated cross mountain ranges, revealing that aspects significantly affected on climate variations and these variations resulted from a larger air circulation system, which were sensitive to global climate change. We conclude that location and terrain of aspect are the main factors affecting differences in climate variation among the mountain ranges with contrasting aspects.

关键词： regional climate variation slope aspect Shennongjia Massif One-way ANOVA global climate change

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Heterogeneity of Surface Heat Exchange of slopes and Potential Drivers of the Initiation of Thaw Slump,Qinghai‑Tibet Plateau

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International Journal of Disaster Risk Science 2023年第4期14卷 549-565页

作者： Xingwen Fan Wenjiao Li Xuyang Wu Miaomiao Yao Fujun Niu Zhanju Lin State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

In the mountainous permafrost area,most thaw slumps are distributed in north or northeast-facing shady slope *** is commonly known that there is a heterogeneity in permafrost between diferent slope aspects,but there has been a lack of detailed measured data to quantitatively evaluate their relationships,and in-depth understandings on how the slope aspects are linked to the distribution of thaw *** study examined the heterogenous thermal regime,soil moisture content,and surface radiation at two slope sites with opposing aspects in a warming permafrost region on the Qinghai-Tibet Plateau(QTP).The results indicate that similar air temperatures(T_(a))were monitored on the two slopes,but there were signifcant diferences in ground temperature and moisture content in the active layer from 2016 to *** sunny slope exhibited a higher mean annual ground surface temperature(T_(s)),and over the fve years the mean annual temperature at the top of permafrost was 1.3–1.4℃warmer on the sunny slope than the shady *** the contrary,the near-surface soil moisture content was about 10–13%lower on the sunny slope(~22–27%)than the shady slope(~35–38%)during the thawing season(June–September).Radiation data indicate that signifcantly higher shortwave downward radiation(DR)appeared at the sunny slope ***,due to the greater surface albedo,the net radiation(Rn)was lower on the sunny *** aspect also afects the ground ice content due to its infuence on ground temperature,freeze-thaw cycles,and soil *** slopes have a shallower burial of ice-rich permafrost compared to sunny *** results highlight greatly diferent near-surface ground thermal conditions at the two slope sites with diferent aspects in a mountainous permafrost *** helps identify the slope-related causes of increasing thaw slumps and provides a basis for predicting their future development.

关键词： Mountainous permafrost slope aspect Soil moisture content Surface heat exchange Thaw slumps

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Environmental Factors that Affect Primary Plant Succession Trajectories on Lahars(Popocatépetl Volcano,Mexico)

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Journal of Mountain Science 2015年第5期12卷 1254-1266页

作者： GARCIA-ROMERO Arturo ALANIS-ANAYA Rocío Marisol MUNOZ-JIMENEZ Julio Departamento de Geografía Física Instituto de GeografíaUniversidad Nacional Autónoma de México.Circuitoexterior s/nCiudad Universitaria04510 MexicoDistrito FederalMexico Laboratorio de Análisis Geoespacial Instituto de GeografíaUniversidad Nacional Autónoma de México.Circuitoexterior s/nCiudad Universitaria04510 MexicoDistrito FederalMexico Departamento de A.G.R.y Geografía Física Facultad de Geografía e HistoriaUniversidad Complutense de Madrid.Calle Profesor Aranguren s/nCiudad Universitaria28040MadridSpain

The earliest stages of plant succession on severely disturbed sites usually follow highly unpredictable trajectories. However, in the Popocatépetl volcano area(50 km SE of Mexico City),the development of physiognomically distinct primary plant communities suggests the occurrence of various successional trajectories only 10 years after the onset of colonization of a temperate forest on lahars. To characterize plant communities and determine the environmental factors that drive the differences observed between plant communities and their successional trajectories, we monitored 64 circular sample plots(3.14 m2) from 2002 to 2011. We examined the plant communities' composition and structure in terms of their species richness and abundance, plant cover, and maximum stem height,and recorded 13 environmental factors related to the volcanic deposit characteristics, microclimate, soil,flow dynamics and gravitational processes. A cluster analysis of the species abundance data showed that,by 2011, six plant community types(CT's) had established, including grasslands, and open, dense and very dense shrub lands. As these communities developed over the same period of time and within the same overall ecosystem, then these plant community types were interpreted as different stages of the same successional trajectory. Two sequential main stages that drive regeneration were identified from this successional trajectory: a) the first four years are characterized by a steady increase in species richness and physiognomic development(plant size and coverage), mostly dominated by Baccharis conferta, Eupatorium glabratum and Senecio barbajohannis; b) from the sixth year onwards, a continued increase in the abundance of those same species led to the development of the dense shrubland *** in the availability of soil resources and disturbances linked to recent lahar flows were the main factors accounting for such differences.

关键词： Ecosystem regeneration Plantcolonization Primary succession Temperate forest Light exposure Elevation Soil slope aspect

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Recent treeline dynamics are similar between dry and mesic areas of Nepal, central Himalaya

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Journal of Plant Ecology 2015年第4期8卷 347-358页

作者： Krishna B.Shrestha Annika Hofgaard Vigdis Vandvik Department of Biology University of BergenPO Box 7803NO-5020BergenNorway UiB Global University of BergenJekteviksbakken 31PO Box 7800NO-5020BergenNorway Norwegian Institute for Nature Research PO Box 5685 SluppenNO-7485TrondheimNorway

Aims We investigated the treeline dynamics of two environmentally con-trasting areas in the Nepalese Himalaya to address the following questions:(i)Does the timing of establishment of the current tree-line differ between the two study areas,and can area-specific tree-line developments be identified?(ii)Do recruitment patterns and height growth indicate recent climate-driven treeline advance,fol-lowing the general prediction for the central Himalayan region,in the two study areas?Methods a dry-climate treeline dominated by Pinus wallichiana and a mesic-climate treeline with Abies spectabilis were selected for *** each area,we sampled the size and age structure of the study spe-cies along three elevational transects(20-m wide)from the forest line to the tree species line crossing the *** also sampled treeline trees from within and outside transects to reconstruct past treeline establishment *** Findings Despite differences in moisture regimes,tree species and recent climate trends,our two study areas showed very similar treeline dynamics over the past six *** both areas,the recruitment of treeline trees indicates stationary treelines over the past six decades with the current treelines being dominated by trees that were established around *** mesic area has experienced an overall climatic warming trend,and the stationary Abies treeline is hypothesized to be regulated by non-climatic factors,notably *** dry area has not experienced warming but increased climatic variability and some very cool summers in the recent dec-ades may explain the stationary to weakly receding Pinus treeline,which appears more climatically controlled with decreased recruit-ment over the past decades and decreased growth towards higher *** both areas,there is a potential for treeline advance,depending on future land use and climate *** results highlight the importance of conducting treeline ecotone analyses for several sites or are

关键词： Abies spectabilis Himalaya Pinus wallichiana slope aspect treeline ecotone dynamics

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