To know the annual water consumption of forest, it is necessary to acquire the annual transpiration value of stands. This paper is based on the data measured in the typical weather of the growth season, from 1998 to 2...To know the annual water consumption of forest, it is necessary to acquire the annual transpiration value of stands. This paper is based on the data measured in the typical weather of the growth season, from 1998 to 2000, with the LI 1600 Steady Porometer and the general weather information. The daily variation of transpiration in black locust forest ( Robinia pesudoacacia L.) is modeled by Penman Monteith equation. As a result of the model, a continuous daily transpiration in the growth season was calculated. The net radiation, intercepted by black locust forest canopy, was acquired from a semi empirical equation of measuring net radiation R n with the extinction coefficient k and leaf area index LAI . The canopy integral stomatic resistance is a mimesis with an empirical equation of measuring data. Compared with measuring data, the relative error of the modeled ones is less than 12% averagely. At last, the total transpiration of black locust forest during the period of 1998 and 2000 in the growth season of May to October, as an average transpiration of the different density stands, were 192 46, 187 07 and 195 59?mm respectively.展开更多
This paper presents a general standard for the low-benefit black locust （Robinia pseudoacacia L.） torests m Loess Plateau based on defining the concept of “tri-low forest”, and emphasizes the major factors which r...This paper presents a general standard for the low-benefit black locust （Robinia pseudoacacia L.） torests m Loess Plateau based on defining the concept of “tri-low forest”, and emphasizes the major factors which result in low-benefit black locust, such as, lack of soil moisture of forest and nutrient, breaching the principle of matching tree species to sites, and high density of forests. Based on different characteristics of low-benefit forests, following the principle of “adjusting measures to local conditions, giving priority to ecological benefits, assisting with economic benefits”, the authors put forward some technical ways to reform low-benefit black locust forests, for example, taking measurements of collecting runoff and storing water, lowering the forest density, introducing mixed forests and transforming species, directive breeding and so on.展开更多
Background:Robinia pseudoacacia is a widely planted pioneer tree species in reforestations on barren mountains in northern China.Because of its nitrogen-fixing ability,it can play a positive role in soil and forest re...Background:Robinia pseudoacacia is a widely planted pioneer tree species in reforestations on barren mountains in northern China.Because of its nitrogen-fixing ability,it can play a positive role in soil and forest restoration.After clearcutting of planted stands,R.pseudoacacia stands become coppice plantations.The impacts of shifting from seedling to coppice stands on soil bacterial community and soil properties have not been wel described.This study aims to quantify how soil properties and bacterial community composition vary between planted seedling versus coppice stands.Methods:Nine 20 m×20 m plots were randomly selected in seedling and coppice stands.The bulk soil and rhizosphere soil were sampled in summer 2017.Bulk soil was sampled at 10 cm from the soil surface using a soil auger.Rhizosphere soil samples were col ected using a brush.The soil samples were transported to the laboratory for chemical analysis,and bacterial community composition and diversity was obtained through DNA extraction,16 S r RNA gene amplification and high-throughput sequencing.Results:The results showed that,compared to seedling plantations,soil quality decreased significantly in coppice stands,but without affecting soil exchangeable Mg^(2+) and K^(+).Total carbon(C)and nitrogen(N)were lower in the rhizosphere than in bulk soil,whereas nutrient availability showed an opposite trend.The conversion from seedling to coppice plantations was also related to significant differences in soil bacterial community structure and to the reduction of soil bacterialα-diversity.Principal component analysis(PCA)showed that bacterial community composition was similar in both bulk and rhizosphere soils in second-generation coppice plantations.Special y,the conversion from seedling to coppice stands increased the relative abundance of Proteobacteria and Rhizobium,but reduced that of Actinobacteria,which may result in a decline of soil nutrient availability.Mantel tests revealed that C,N,soil organic matter(SOM),nitrate nitrogen(NO^(-)+(3)-N)and available phosphorus positively correlated with bacterial community composition,while a variation partition analysis(VPA)showed that NO^(-)+(3)-N explained a relatively greater proportion of bacterial distribution(15.12%),compared with C and SOM.Surprisingly,N showed no relationship with bacterial community composition,which may be related to nitrogen transportation.Conclusions:The conversion from seedling to coppice stands reduced soil quality and led to spatial-temporal homogenization of the soil bacterial community structure in both the rhizosphere and bulk soils.Such imbalance in microbial structure can accelerate the decline of R.pseudoacacia.This may affect the role of R.pseudoacacia coppice stands in soil and forest restoration of barren lands in mountain areas.展开更多
Plantations of woody tree species play a crucial role in ecological security along coastal zones.Understanding energy partitioning and evapotranspiration can reveal land–atmosphere interaction processes.We investigat...Plantations of woody tree species play a crucial role in ecological security along coastal zones.Understanding energy partitioning and evapotranspiration can reveal land–atmosphere interaction processes.We investigated energy fluxes,evapotranspiration,and their related biophysical factors using eddy covariance techniques in a black locust(Robinia pseudoacacia L.)plantation in 2016,2018,and 2019 on the Yellow River Delta.Downward longwave radiation offsets 84–85%of upward longwave radiation;upward shortwave radiation accounted for 12–13%of downward shortwave radiation.The ratio of net radiation to downward radiation was 18–19%over the three years.During the growing season,latent heat flux was the largest component of net radiation;during the dormant season,the sensible heat flux was the dominant component of net radiation.The seasonal variation in daily evapotranspiration was mainly controlled by net radiation,air temperature,vapor pressure deficit,and leaf area index.Black locust phenology influenced daily evapotranspiration variations,and evapotranspiration was greater under sea winds than under land winds because soil water content at 10-cm depth was greater under sea winds during the day.Seasonal patterns of daily evaporative fraction,Bowen ratio,crop coefficient,Priestley–Taylor coefficient,surface conductance,and decoupling coefficient were mainly controlled by leaf area index.The threshold value of daily surface conductance was approximately 8 mm sover the plantation.展开更多
Black locust(Robinia pseudoacacia L.)plantations have contributed significantly to soil and water conservation and ecological reconstruction on China’s Loess Plateau.Understanding the impact of stand and environment ...Black locust(Robinia pseudoacacia L.)plantations have contributed significantly to soil and water conservation and ecological reconstruction on China’s Loess Plateau.Understanding the impact of stand and environment on species composition of understory woody plants will improve the stability of existing black locust plantations.Ten stands were selected in second-generation black locust plantations in tableland and gully areas of the Loess Plateau.The number of understory tree species in the tablelands was significantly lower than in the gully stands.Regenerated black locust(19.76%)and Rubus corchorifolius L.f.(64.85%)were the most abundant understory tree and shrub species,respectively,in the tableland stands;Broussonetia papyrifera(L.)L’Hér.ex Vent.(6.77%)and Acanthopanax senticosus(Rupr.Maxim.)Harms.(37.22%)were most abundant in the gully stands.Species richness(S),Shannon diversity(H),and evenness index(J)of the understory plants were significantly lower in the tableland stands than in the gully stands.More diverse understory species and community structures occurred in the gully stands.Differences in species diversity among landform positions may be attributed to differences in soil moisture.In addition,77.57%of the variation in understory species composition was explained,among which shrub and herb coverage,stand age,leaf area index,slope and total soil phosphorus in the 10-20 cm layer were the main factors.Soil organic carbon and total potassium significantly impacted S,H and J.Considering the environmental conditions and the biological characteristics of the plants investigated,R.corchorifolius should be given priority in the development of tableland stands,while B.papyrifera and Celtis sinensis Pers.should form mixed forests with black locust in gully stands.This management could promote biodiversity and stability of the existing black locust plantations but also optimize regional landscape patterns.展开更多
The alien woody legume, black locust （Robinia pseudoaca-cia）, has invaded Japanese black pine （Pinus thunbergii） forests located in Japan’s coastal plain and hill regions where gaps are formed in pine forests aft...The alien woody legume, black locust （Robinia pseudoaca-cia）, has invaded Japanese black pine （Pinus thunbergii） forests located in Japan’s coastal plain and hill regions where gaps are formed in pine forests after nematode infestation. Nitrogen fixation by legumes acceler-ates N cycling in forest ecosystems. We studied temporal change in the annual tree-ring resolution N stable isotope composition （δ15N, a per mil deviation of δ15N/14N ratio, relative to atmospheric N2δ15N=0‰） at two natural locations of Japanese black pine forest with black locust that differed in the time since black locust establishment （Shohnai in north-east and Kita-Kyushu in southwest Japan）. Analyzed tree-rings covered the period from 1990/1992 to 2009. N acquisition by Japanese black pine from black locust N input to the soil was evidenced by temporal shifting of N stable isotope composition on the annual pine tree rings. With pro-gressive development of the forest stand,δ15N values of earlier tree-ringsδ15N of -5‰） from black pine associated with black locust shifted to-wards values similar to those of black locustδ15N values nearly to-1‰）, which suggests acquisition of N by N2 fixation （Shohnai site）. In con-trast, in a forest where black locust had settled for two or three genera-tions, in a black pine stand （Kita-Kyushu site）, longer periods of N en-richment in the soil were reflected in the elevated tree-ringδ15N values of newly established black pine trees. Based on tree-ringδ15N data from the Shohnai site, we determined that about 10 years after black locust establishment, soil N had already been enriched by black locust N, this, in turn, contributed to N fertilization of surrounding trees in mixed stands.展开更多
Black locust(Robinia pseudoacacia L.),a species native to the eastern North America,was introduced to Europe probably in 1601 and currently extends over2.3×10~6 ha.It has become naturalized in all sub-Mediterrane...Black locust(Robinia pseudoacacia L.),a species native to the eastern North America,was introduced to Europe probably in 1601 and currently extends over2.3×10~6 ha.It has become naturalized in all sub-Mediterranean and temperate regions rivaling Populus spp.as the second most planted broadleaved tree species worldwide after Eucalyptus spp.This wide-spreading planting is because black locust is an important multipurpose species,producing wood,fodder,and a source of honey as well as bio-oil and biomass.It is also important for carbon sequestration,soil stabilization and re-vegetation of landfills,mining areas and wastelands,in biotherapy and landscaping.In Europe,black locust is drought tolerant so grows in areas with annual precipitation as low as 500-550 mm.It tolerates dry,nutrient poor soils but grows best on deep,nutrient-rich,well-drained soils.It is a fast-growing tree and the height,diameter and volume growth peak before the age of 20.It mostly regenerates vegetatively by root suckers under a simple coppice system,which is considered the most cost-effective management system.It also regenerates,but less frequently,by stool sprouts.Its early silviculture in production forests includes release cutting to promote root suckers rather than stool shoots,and cleaning-respacing to remove low-quality stems,reduce the number of shoots per stool,and adjust spacing between root suckers.In addition,early,moderate and frequent thinning as well as limited pruning are carried out focusing on crop trees.The species is regarded as invasive in several European countries and its range here is expected to expand under predicted climate changes.展开更多
How can we regulate an invasive alien species of high commercial value?Black locust(Robinia pseudoacacia L.)has a unique capacity for seed dispersal and high germination.Field surveys indicate that black locust increa...How can we regulate an invasive alien species of high commercial value?Black locust(Robinia pseudoacacia L.)has a unique capacity for seed dispersal and high germination.Field surveys indicate that black locust increases its growing area with sprouting roots and the elongation of horizontal roots at a soil depth of 10 cm.Therefore,a method to regulate the development of horizontal roots could be eff ective in slowing the invasiveness of black locust.In this study,root barrier panels were tested to inhibit the growth of horizontal roots.Since it is labor intensive to observe the growth of roots in the fi eld,it was investigated in a nursery setting.The decrease in secondary fl ush,an increase in yellowed leafl ets,and the height in the seedlings were measured.Installing root barrier panels to a depth of 30 cm eff ectively inhibit the growth of horizontal roots of young black locust.展开更多
Robinia pseudoacacia is an important afforesta-tion tree introduced to China in 1878.In the present study,we examined the genetic diversity among 687 strains rep-resenting four improved varieties and two secondary pro...Robinia pseudoacacia is an important afforesta-tion tree introduced to China in 1878.In the present study,we examined the genetic diversity among 687 strains rep-resenting four improved varieties and two secondary prov-enances,comprising 641 clones and 46 seedlings.Ninety-one simple sequence repeats(SSRs)were selected through segregation analysis and polymorphism characterization,and all sampled individuals were genotyped using well-characterized SSR markers.After excluding loci with non-neutral equilibrium,missing locus data and null alleles,we used 36 primer pairs to assess the genetic diversity of these germplasm resources,revealing vast genetic differentiation among the samples,with an average of 8.352 alleles per locus and a mean Shannon′s index of 1.302.At the popula-tion level,the partitioning of variability was assessed using analysis of molecular variance,which revealed 93%and 7%variation within and among collection sites,respectively.Four clusters were detected using structure analysis,indi-cating a degree of genetic differentiation among the six populations.Insights into the genetic diversity and structure of R.pseudoacacia provide a theoretical basis for the con-servation,breeding and sustainable development in China.展开更多
Fine roots are the most active and functional component of root systems and play a significant role in the acquisition of soil resources. Density is an important structural factor in forest plantations but information...Fine roots are the most active and functional component of root systems and play a significant role in the acquisition of soil resources. Density is an important structural factor in forest plantations but information on changes in fine roots along a density gradient is limited. In this study, plantations of black locust (Robinia pseudoacacia L.) and Chinese pine (Pinus tabuliformis Carr.) with four density classes were analyzed for the influence of soil and leaf traits on fine root growth. Fine root biomass increased with stand density. High fine root biomass was achieved through increases in the fine root production and turnover rate in the high-density black locust plantations and through an increase in fine root production in the pine plantations. In the high-density Chinese pine stand, there was a high fine root turnover which, coupled with high fine root production, contributed to a high fine root biomass. Overall, fine root production and turnover rate were closely related to soil volumetric water content in both kinds of plantations, while fine root biomass, especially the component of necromass, was related to soil nutrient status, which refers to phosphorous content in black locust plantations and nitrogen content in Chinese pine plantations. There was a close linkage between leaf area index and fine root dynamics in the black locust plantations but not in the pine plantations.展开更多
Background:Black locust(BL,Robinia pseudoacacia)is considered a promising tree species for reforestation due to its great ability to fix nitrogen.However,after two or three coppice-harvesting rotations,the productivit...Background:Black locust(BL,Robinia pseudoacacia)is considered a promising tree species for reforestation due to its great ability to fix nitrogen.However,after two or three coppice-harvesting rotations,the productivity of BL declines.Whether soil microbial communities are affected and how these groups correlate with the nitrogen mineralization process across multi-generation stands remains unclear.Methods:We investigated the composition and structure of free-living nitrogen-fixing microorganisms(diazotrophs)by sequencing the marker gene nifH and compared these results to levels of soil nitrogen mineralization in the bulk soil and rhizosphere in black locust plantations on Mount Tai,China.Results:The results showed multi-generation BL coppice plantations decreased the total soil nitrogen(N),soil phosphorus(P),soil microbial biomass N(MBN),soil microbial biomass C(MBC),soil nitrification rate(Rn),soil ammonification rate(Ra),and net soil N mineralization rate(Rm),but significantly increased the concentration of soil NH_(4þ)-N to maintain sufficient NO_(3)^(-)N.The dominant species in bulk soil and rhizosphere changed from Rhodopseudomonas(22.62%and 15.76%),unclassified_c_Alphaproteobacteria(22.37%and 29.28%),unclassified_o_Rhizobiales(15.40%and 13.31%),Bradyrhizobium(12.00%and 11.74%)in seedling plantations to Bradyrhizobium(45.95%and 47.86%)and Rhodopseudomonas(43.56%and 41.84%)in coppice plantations,respectively.Mantel test and Redundancy analysis(RDA)revealed that Rn,Ra,and Rm were the most important factors shaping the diazotrophic communities.Conclusions:Our results suggest that the multi-generation BL coppice plantation can homogenize soil diazotrophic communities,which is mainly regulated by the available N loss caused by nitrogen mineralization.Strengthening the management technology of coppice plantations will provide more beneficial external consumption.展开更多
Black locust (Robinia pseudoacacia L.) is one of the most important stand-forming tree species in Hungary and its importance is increasing in many countries. Black locust plants are commonly produced by two methods, b...Black locust (Robinia pseudoacacia L.) is one of the most important stand-forming tree species in Hungary and its importance is increasing in many countries. Black locust plants are commonly produced by two methods, by seed and by root cuttings. Tissue culture propagation can be considered as a relatively new method. Growing trees from seed is a relatively sim-ple method for reliably producing seedlings on a large scale under a variety of circumstances. Mechanization of the method is easy and the production cost is relatively low. Propagation from root cuttings and tissue culture are valuable for reproduction of superior individuals or varieties. By applying these methods, superior traits of the selected trees can be preserved in the clones. Recent experiments demonstrated that micropropagated trees could be successfully transplanted into soil, hardened and grown in the field.展开更多
Black locust (Robinia pseudoacacia L.) was the first forest tree species to be imported from North America to Europe at the beginning of the 17th century. It is the most important fast-growing stand-forming tree speci...Black locust (Robinia pseudoacacia L.) was the first forest tree species to be imported from North America to Europe at the beginning of the 17th century. It is the most important fast-growing stand-forming tree species in Hungary. Black locust planta-tions can be successfully established in response to a range of economic and ecological opportunities. Plantation survival and productivity are maximized by matching the species' growth characteristics with silvicultural options and land management needs. In the paper the sequence of forest tending operations in black locust stands is proposed, based on results of long-term stand structure and forest yield trials. Implementing good silvicultural plans and models will lead to profitable black locust stands and greater ac-ceptance of the species by land managers. Black locust would also be a very useful species for energy productions as the related research results have been shown in the paper.展开更多
The AhDREB1 gene, cloned from Atriplex hortensis L., was transferred into black locust （Robiniapseudoacacia L.） by an Agrobacterium-mediated transformation. The results suggest that stems of black locust sub-culture...The AhDREB1 gene, cloned from Atriplex hortensis L., was transferred into black locust （Robiniapseudoacacia L.） by an Agrobacterium-mediated transformation. The results suggest that stems of black locust sub-cultured in vitro for 20 d are suitable for genetic transformation. The optimum concentrations of kanamycin and cefotaxime were 30 and 150 mg.L-1, respectively. Important factors affecting the transformation efficiency were studied by means of a L9（3^4） orthogonal design. An effective system for genetic transformation in black locust was developed as follows： the stems were pre-cultured for 2 d, immersed in the Agrobacterium solution （OD600 = 0.7） with 10 mg·L^-1 acetosyringone for 21 min and then co-cultured for 2 d. The selection pressures, changing from low to high, could improve transformation efficiency. The transgenic plants were identified by a PCR method. The PCR results indicated that the AhDREB1 gene had been integrated into the genome of black locust and two lines of the transgenic plants were obtained.展开更多
Tetraploid black locust （Robinia pseudoacacia） is a woody plant with larger leaves and richer nutritional content than normal diploid black locust, with greater biomass and wider adaptability than herbaceous plant f...Tetraploid black locust （Robinia pseudoacacia） is a woody plant with larger leaves and richer nutritional content than normal diploid black locust, with greater biomass and wider adaptability than herbaceous plant forage. However, currently no stock- breeders have adopted it as a major forage in China and other countries for a lack of information on the evaluation of nutritional ingredients of leaves and stems of young tetraploid black locust （YTBL） by in situ digesting tests. The objectives of this study were： 1） to assess the nutritive value of YTBL that bourgeoned from root stumps in the spring by determining the ruminal in situ disappearance kinetics of dry matter （DM）, organic matter （OM）, crude protein （CP）, ether extract （EE）, neutral detergent fiber （NDF） and acid detergent fiber （ADF） from leaves, stems and a mixture of both leaves and stems （MLS） of YTBL; 2） to compare these kinetic estimates with those of Leymus chinensis, a widely used ruminant forage in China. All samples were evaluated in situ by using five ruminally cannulated crossbred steers （550±22.7 kg BW）. The results of 48 hours, the representative incubation period, indicate that in situ disappearance rates of DM and OM in YTBL leaves, stems and MLS are on average about 40% and can attain the level of digestibility of L. chinensis. In situ disappearance rates of leaves, stems and MLS of YTBL for CP and EE were 41% and 58% respectively, rates higher than those of L. chinensis. But the disappearance rates of NDF and ADF were, on average, respectively 30.62% and 24.89% and lower than those ofL. chinensis. By analyzing synthetically all of our results it could be inferred that MLS of YTBL offers effective ruminal degradability of DM, NDF, ADF, CP, EE and OM, similar to the nutrients of L. chinensis. This supports our contention that the YTBL leaves, stems and MLS are suitable feed for those ruminants requiring high levels of nutrients, such as dairy cows and Boer goats, instead of plant forage, which is decidedly lacking in some parts of the world.展开更多
Black locust （Robinia pseudoacacia L.） is one of the most important stand-forming tree species in Hungary and its impor- tance is increasing in many countries. The main aim of the discussed new selection programme i...Black locust （Robinia pseudoacacia L.） is one of the most important stand-forming tree species in Hungary and its impor- tance is increasing in many countries. The main aim of the discussed new selection programme is to identify black locust clones with good performance and good form for setting up clonal seed orchards. As a result of selection programme 16 new black locust clones have been improved. In spring 2002 a black locust seed orchard was established with the newly selected clones. About 40% of the plants can be considered to belong to the height growth rate class 1 and 2. Hungary was the first country where micropropagated black locust planting material was used for seed orchard establishment.展开更多
基金SupportedbytheNationalNaturalScienceFoundationofChina(39970 6 2 2 )andtheTeachingandResearchAwardProgramforYongCadremanTeachersinHigherEducationInstitutionsofMOE P .R .China
文摘To know the annual water consumption of forest, it is necessary to acquire the annual transpiration value of stands. This paper is based on the data measured in the typical weather of the growth season, from 1998 to 2000, with the LI 1600 Steady Porometer and the general weather information. The daily variation of transpiration in black locust forest ( Robinia pesudoacacia L.) is modeled by Penman Monteith equation. As a result of the model, a continuous daily transpiration in the growth season was calculated. The net radiation, intercepted by black locust forest canopy, was acquired from a semi empirical equation of measuring net radiation R n with the extinction coefficient k and leaf area index LAI . The canopy integral stomatic resistance is a mimesis with an empirical equation of measuring data. Compared with measuring data, the relative error of the modeled ones is less than 12% averagely. At last, the total transpiration of black locust forest during the period of 1998 and 2000 in the growth season of May to October, as an average transpiration of the different density stands, were 192 46, 187 07 and 195 59?mm respectively.
文摘This paper presents a general standard for the low-benefit black locust （Robinia pseudoacacia L.） torests m Loess Plateau based on defining the concept of “tri-low forest”, and emphasizes the major factors which result in low-benefit black locust, such as, lack of soil moisture of forest and nutrient, breaching the principle of matching tree species to sites, and high density of forests. Based on different characteristics of low-benefit forests, following the principle of “adjusting measures to local conditions, giving priority to ecological benefits, assisting with economic benefits”, the authors put forward some technical ways to reform low-benefit black locust forests, for example, taking measurements of collecting runoff and storing water, lowering the forest density, introducing mixed forests and transforming species, directive breeding and so on.
基金financially supported by the Special Fund for Forestry Scientific Research in the Public Interest No.201504406the National Natural Science Foundation of China(Nos.31570705,31500362,31700553)+4 种基金the Shandong Provincial Natural Science Foundation,China(No.ZR2016CP01)the Project of Shandong Province Higher Educational Science and Technology Program(No.J16LF09)China Scholarship Council(No.201809135006)The contribution of S.de-Miguel was supported by the Spanish Ministry of Economy and Competitivity(MINECO)(Grant No.RTI2018–099315-A-I00)by a Serra-Húnter Fellowship provided by the Generalitat of Catalonia。
文摘Background:Robinia pseudoacacia is a widely planted pioneer tree species in reforestations on barren mountains in northern China.Because of its nitrogen-fixing ability,it can play a positive role in soil and forest restoration.After clearcutting of planted stands,R.pseudoacacia stands become coppice plantations.The impacts of shifting from seedling to coppice stands on soil bacterial community and soil properties have not been wel described.This study aims to quantify how soil properties and bacterial community composition vary between planted seedling versus coppice stands.Methods:Nine 20 m×20 m plots were randomly selected in seedling and coppice stands.The bulk soil and rhizosphere soil were sampled in summer 2017.Bulk soil was sampled at 10 cm from the soil surface using a soil auger.Rhizosphere soil samples were col ected using a brush.The soil samples were transported to the laboratory for chemical analysis,and bacterial community composition and diversity was obtained through DNA extraction,16 S r RNA gene amplification and high-throughput sequencing.Results:The results showed that,compared to seedling plantations,soil quality decreased significantly in coppice stands,but without affecting soil exchangeable Mg^(2+) and K^(+).Total carbon(C)and nitrogen(N)were lower in the rhizosphere than in bulk soil,whereas nutrient availability showed an opposite trend.The conversion from seedling to coppice plantations was also related to significant differences in soil bacterial community structure and to the reduction of soil bacterialα-diversity.Principal component analysis(PCA)showed that bacterial community composition was similar in both bulk and rhizosphere soils in second-generation coppice plantations.Special y,the conversion from seedling to coppice stands increased the relative abundance of Proteobacteria and Rhizobium,but reduced that of Actinobacteria,which may result in a decline of soil nutrient availability.Mantel tests revealed that C,N,soil organic matter(SOM),nitrate nitrogen(NO^(-)+(3)-N)and available phosphorus positively correlated with bacterial community composition,while a variation partition analysis(VPA)showed that NO^(-)+(3)-N explained a relatively greater proportion of bacterial distribution(15.12%),compared with C and SOM.Surprisingly,N showed no relationship with bacterial community composition,which may be related to nitrogen transportation.Conclusions:The conversion from seedling to coppice stands reduced soil quality and led to spatial-temporal homogenization of the soil bacterial community structure in both the rhizosphere and bulk soils.Such imbalance in microbial structure can accelerate the decline of R.pseudoacacia.This may affect the role of R.pseudoacacia coppice stands in soil and forest restoration of barren lands in mountain areas.
基金supported financially by the Fundamental Research Funds for the Central Nonprofit Research Institution of CAF(CAFYBB2019SY007,CAFYBB2018ZA001,CAFYBB2020SZ001-3)。
文摘Plantations of woody tree species play a crucial role in ecological security along coastal zones.Understanding energy partitioning and evapotranspiration can reveal land–atmosphere interaction processes.We investigated energy fluxes,evapotranspiration,and their related biophysical factors using eddy covariance techniques in a black locust(Robinia pseudoacacia L.)plantation in 2016,2018,and 2019 on the Yellow River Delta.Downward longwave radiation offsets 84–85%of upward longwave radiation;upward shortwave radiation accounted for 12–13%of downward shortwave radiation.The ratio of net radiation to downward radiation was 18–19%over the three years.During the growing season,latent heat flux was the largest component of net radiation;during the dormant season,the sensible heat flux was the dominant component of net radiation.The seasonal variation in daily evapotranspiration was mainly controlled by net radiation,air temperature,vapor pressure deficit,and leaf area index.Black locust phenology influenced daily evapotranspiration variations,and evapotranspiration was greater under sea winds than under land winds because soil water content at 10-cm depth was greater under sea winds during the day.Seasonal patterns of daily evaporative fraction,Bowen ratio,crop coefficient,Priestley–Taylor coefficient,surface conductance,and decoupling coefficient were mainly controlled by leaf area index.The threshold value of daily surface conductance was approximately 8 mm sover the plantation.
基金supported by the National Natural Science Foundation of China[32101511]the Chinese Universities Scientific Fund[2452020137]and[2452021073]the Natural Science Basic Research Program of Shaanxi[2021JQ-155]。
文摘Black locust(Robinia pseudoacacia L.)plantations have contributed significantly to soil and water conservation and ecological reconstruction on China’s Loess Plateau.Understanding the impact of stand and environment on species composition of understory woody plants will improve the stability of existing black locust plantations.Ten stands were selected in second-generation black locust plantations in tableland and gully areas of the Loess Plateau.The number of understory tree species in the tablelands was significantly lower than in the gully stands.Regenerated black locust(19.76%)and Rubus corchorifolius L.f.(64.85%)were the most abundant understory tree and shrub species,respectively,in the tableland stands;Broussonetia papyrifera(L.)L’Hér.ex Vent.(6.77%)and Acanthopanax senticosus(Rupr.Maxim.)Harms.(37.22%)were most abundant in the gully stands.Species richness(S),Shannon diversity(H),and evenness index(J)of the understory plants were significantly lower in the tableland stands than in the gully stands.More diverse understory species and community structures occurred in the gully stands.Differences in species diversity among landform positions may be attributed to differences in soil moisture.In addition,77.57%of the variation in understory species composition was explained,among which shrub and herb coverage,stand age,leaf area index,slope and total soil phosphorus in the 10-20 cm layer were the main factors.Soil organic carbon and total potassium significantly impacted S,H and J.Considering the environmental conditions and the biological characteristics of the plants investigated,R.corchorifolius should be given priority in the development of tableland stands,while B.papyrifera and Celtis sinensis Pers.should form mixed forests with black locust in gully stands.This management could promote biodiversity and stability of the existing black locust plantations but also optimize regional landscape patterns.
文摘The alien woody legume, black locust （Robinia pseudoaca-cia）, has invaded Japanese black pine （Pinus thunbergii） forests located in Japan’s coastal plain and hill regions where gaps are formed in pine forests after nematode infestation. Nitrogen fixation by legumes acceler-ates N cycling in forest ecosystems. We studied temporal change in the annual tree-ring resolution N stable isotope composition （δ15N, a per mil deviation of δ15N/14N ratio, relative to atmospheric N2δ15N=0‰） at two natural locations of Japanese black pine forest with black locust that differed in the time since black locust establishment （Shohnai in north-east and Kita-Kyushu in southwest Japan）. Analyzed tree-rings covered the period from 1990/1992 to 2009. N acquisition by Japanese black pine from black locust N input to the soil was evidenced by temporal shifting of N stable isotope composition on the annual pine tree rings. With pro-gressive development of the forest stand,δ15N values of earlier tree-ringsδ15N of -5‰） from black pine associated with black locust shifted to-wards values similar to those of black locustδ15N values nearly to-1‰）, which suggests acquisition of N by N2 fixation （Shohnai site）. In con-trast, in a forest where black locust had settled for two or three genera-tions, in a black pine stand （Kita-Kyushu site）, longer periods of N en-richment in the soil were reflected in the elevated tree-ringδ15N values of newly established black pine trees. Based on tree-ringδ15N data from the Shohnai site, we determined that about 10 years after black locust establishment, soil N had already been enriched by black locust N, this, in turn, contributed to N fertilization of surrounding trees in mixed stands.
基金funded by any source but carried out voluntarily by a group of people (university staff,researchers,practitioners) interested in the ecology,growth and yield and management of black locust
文摘Black locust(Robinia pseudoacacia L.),a species native to the eastern North America,was introduced to Europe probably in 1601 and currently extends over2.3×10~6 ha.It has become naturalized in all sub-Mediterranean and temperate regions rivaling Populus spp.as the second most planted broadleaved tree species worldwide after Eucalyptus spp.This wide-spreading planting is because black locust is an important multipurpose species,producing wood,fodder,and a source of honey as well as bio-oil and biomass.It is also important for carbon sequestration,soil stabilization and re-vegetation of landfills,mining areas and wastelands,in biotherapy and landscaping.In Europe,black locust is drought tolerant so grows in areas with annual precipitation as low as 500-550 mm.It tolerates dry,nutrient poor soils but grows best on deep,nutrient-rich,well-drained soils.It is a fast-growing tree and the height,diameter and volume growth peak before the age of 20.It mostly regenerates vegetatively by root suckers under a simple coppice system,which is considered the most cost-effective management system.It also regenerates,but less frequently,by stool sprouts.Its early silviculture in production forests includes release cutting to promote root suckers rather than stool shoots,and cleaning-respacing to remove low-quality stems,reduce the number of shoots per stool,and adjust spacing between root suckers.In addition,early,moderate and frequent thinning as well as limited pruning are carried out focusing on crop trees.The species is regarded as invasive in several European countries and its range here is expected to expand under predicted climate changes.
基金supported in part by the Research Faculty of Agriculture of Hokkaido University.
文摘How can we regulate an invasive alien species of high commercial value?Black locust(Robinia pseudoacacia L.)has a unique capacity for seed dispersal and high germination.Field surveys indicate that black locust increases its growing area with sprouting roots and the elongation of horizontal roots at a soil depth of 10 cm.Therefore,a method to regulate the development of horizontal roots could be eff ective in slowing the invasiveness of black locust.In this study,root barrier panels were tested to inhibit the growth of horizontal roots.Since it is labor intensive to observe the growth of roots in the fi eld,it was investigated in a nursery setting.The decrease in secondary fl ush,an increase in yellowed leafl ets,and the height in the seedlings were measured.Installing root barrier panels to a depth of 30 cm eff ectively inhibit the growth of horizontal roots of young black locust.
基金This work was supported by the Doctoral Scientific Research Starting Foundation of Henan University of Science and Technology(13480089)National Nature Science Foundation of China(31570677)+1 种基金the National Key R&D Program of China(2017YFD0600503)the National Forestry and Grassland Administration of Science and Technology Development Center Project(2016007).
文摘Robinia pseudoacacia is an important afforesta-tion tree introduced to China in 1878.In the present study,we examined the genetic diversity among 687 strains rep-resenting four improved varieties and two secondary prov-enances,comprising 641 clones and 46 seedlings.Ninety-one simple sequence repeats(SSRs)were selected through segregation analysis and polymorphism characterization,and all sampled individuals were genotyped using well-characterized SSR markers.After excluding loci with non-neutral equilibrium,missing locus data and null alleles,we used 36 primer pairs to assess the genetic diversity of these germplasm resources,revealing vast genetic differentiation among the samples,with an average of 8.352 alleles per locus and a mean Shannon′s index of 1.302.At the popula-tion level,the partitioning of variability was assessed using analysis of molecular variance,which revealed 93%and 7%variation within and among collection sites,respectively.Four clusters were detected using structure analysis,indi-cating a degree of genetic differentiation among the six populations.Insights into the genetic diversity and structure of R.pseudoacacia provide a theoretical basis for the con-servation,breeding and sustainable development in China.
基金The study was financially supported by the National Key R&D Program of China(2017YFC0504601).
文摘Fine roots are the most active and functional component of root systems and play a significant role in the acquisition of soil resources. Density is an important structural factor in forest plantations but information on changes in fine roots along a density gradient is limited. In this study, plantations of black locust (Robinia pseudoacacia L.) and Chinese pine (Pinus tabuliformis Carr.) with four density classes were analyzed for the influence of soil and leaf traits on fine root growth. Fine root biomass increased with stand density. High fine root biomass was achieved through increases in the fine root production and turnover rate in the high-density black locust plantations and through an increase in fine root production in the pine plantations. In the high-density Chinese pine stand, there was a high fine root turnover which, coupled with high fine root production, contributed to a high fine root biomass. Overall, fine root production and turnover rate were closely related to soil volumetric water content in both kinds of plantations, while fine root biomass, especially the component of necromass, was related to soil nutrient status, which refers to phosphorous content in black locust plantations and nitrogen content in Chinese pine plantations. There was a close linkage between leaf area index and fine root dynamics in the black locust plantations but not in the pine plantations.
基金supported by the Agricultural Science and Technology Fund for Forestry Sci-tech Innovation Project of Shandong Province (No.2019LY005)the National Natural Science Foundation of China (No.31570705)+1 种基金Shandong Province Higher School Science and Technology Plan Project (No. J16LF09)and Shandong Province Natural Science Foundation (No. ZR2018PC006)
文摘Background:Black locust(BL,Robinia pseudoacacia)is considered a promising tree species for reforestation due to its great ability to fix nitrogen.However,after two or three coppice-harvesting rotations,the productivity of BL declines.Whether soil microbial communities are affected and how these groups correlate with the nitrogen mineralization process across multi-generation stands remains unclear.Methods:We investigated the composition and structure of free-living nitrogen-fixing microorganisms(diazotrophs)by sequencing the marker gene nifH and compared these results to levels of soil nitrogen mineralization in the bulk soil and rhizosphere in black locust plantations on Mount Tai,China.Results:The results showed multi-generation BL coppice plantations decreased the total soil nitrogen(N),soil phosphorus(P),soil microbial biomass N(MBN),soil microbial biomass C(MBC),soil nitrification rate(Rn),soil ammonification rate(Ra),and net soil N mineralization rate(Rm),but significantly increased the concentration of soil NH_(4þ)-N to maintain sufficient NO_(3)^(-)N.The dominant species in bulk soil and rhizosphere changed from Rhodopseudomonas(22.62%and 15.76%),unclassified_c_Alphaproteobacteria(22.37%and 29.28%),unclassified_o_Rhizobiales(15.40%and 13.31%),Bradyrhizobium(12.00%and 11.74%)in seedling plantations to Bradyrhizobium(45.95%and 47.86%)and Rhodopseudomonas(43.56%and 41.84%)in coppice plantations,respectively.Mantel test and Redundancy analysis(RDA)revealed that Rn,Ra,and Rm were the most important factors shaping the diazotrophic communities.Conclusions:Our results suggest that the multi-generation BL coppice plantation can homogenize soil diazotrophic communities,which is mainly regulated by the available N loss caused by nitrogen mineralization.Strengthening the management technology of coppice plantations will provide more beneficial external consumption.
基金the Hungarian National Sci-entific Research Fund (OTKA-T 029021) and the Hungar- ian Ministry of Agriculture and Region Development (95-a/2001).
文摘Black locust (Robinia pseudoacacia L.) is one of the most important stand-forming tree species in Hungary and its importance is increasing in many countries. Black locust plants are commonly produced by two methods, by seed and by root cuttings. Tissue culture propagation can be considered as a relatively new method. Growing trees from seed is a relatively sim-ple method for reliably producing seedlings on a large scale under a variety of circumstances. Mechanization of the method is easy and the production cost is relatively low. Propagation from root cuttings and tissue culture are valuable for reproduction of superior individuals or varieties. By applying these methods, superior traits of the selected trees can be preserved in the clones. Recent experiments demonstrated that micropropagated trees could be successfully transplanted into soil, hardened and grown in the field.
文摘Black locust (Robinia pseudoacacia L.) was the first forest tree species to be imported from North America to Europe at the beginning of the 17th century. It is the most important fast-growing stand-forming tree species in Hungary. Black locust planta-tions can be successfully established in response to a range of economic and ecological opportunities. Plantation survival and productivity are maximized by matching the species' growth characteristics with silvicultural options and land management needs. In the paper the sequence of forest tending operations in black locust stands is proposed, based on results of long-term stand structure and forest yield trials. Implementing good silvicultural plans and models will lead to profitable black locust stands and greater ac-ceptance of the species by land managers. Black locust would also be a very useful species for energy productions as the related research results have been shown in the paper.
基金supported by the Key Extended Project of State Forestry Administration, China (Grant No. 2003-5-2).
文摘The AhDREB1 gene, cloned from Atriplex hortensis L., was transferred into black locust （Robiniapseudoacacia L.） by an Agrobacterium-mediated transformation. The results suggest that stems of black locust sub-cultured in vitro for 20 d are suitable for genetic transformation. The optimum concentrations of kanamycin and cefotaxime were 30 and 150 mg.L-1, respectively. Important factors affecting the transformation efficiency were studied by means of a L9（3^4） orthogonal design. An effective system for genetic transformation in black locust was developed as follows： the stems were pre-cultured for 2 d, immersed in the Agrobacterium solution （OD600 = 0.7） with 10 mg·L^-1 acetosyringone for 21 min and then co-cultured for 2 d. The selection pressures, changing from low to high, could improve transformation efficiency. The transgenic plants were identified by a PCR method. The PCR results indicated that the AhDREB1 gene had been integrated into the genome of black locust and two lines of the transgenic plants were obtained.
基金supported by the Ministry of Science and Technology of China (Grant No. 003EFN216700307)the State Forestry Admini-stration of China (No. 2003–5–2)
文摘Tetraploid black locust （Robinia pseudoacacia） is a woody plant with larger leaves and richer nutritional content than normal diploid black locust, with greater biomass and wider adaptability than herbaceous plant forage. However, currently no stock- breeders have adopted it as a major forage in China and other countries for a lack of information on the evaluation of nutritional ingredients of leaves and stems of young tetraploid black locust （YTBL） by in situ digesting tests. The objectives of this study were： 1） to assess the nutritive value of YTBL that bourgeoned from root stumps in the spring by determining the ruminal in situ disappearance kinetics of dry matter （DM）, organic matter （OM）, crude protein （CP）, ether extract （EE）, neutral detergent fiber （NDF） and acid detergent fiber （ADF） from leaves, stems and a mixture of both leaves and stems （MLS） of YTBL; 2） to compare these kinetic estimates with those of Leymus chinensis, a widely used ruminant forage in China. All samples were evaluated in situ by using five ruminally cannulated crossbred steers （550±22.7 kg BW）. The results of 48 hours, the representative incubation period, indicate that in situ disappearance rates of DM and OM in YTBL leaves, stems and MLS are on average about 40% and can attain the level of digestibility of L. chinensis. In situ disappearance rates of leaves, stems and MLS of YTBL for CP and EE were 41% and 58% respectively, rates higher than those of L. chinensis. But the disappearance rates of NDF and ADF were, on average, respectively 30.62% and 24.89% and lower than those ofL. chinensis. By analyzing synthetically all of our results it could be inferred that MLS of YTBL offers effective ruminal degradability of DM, NDF, ADF, CP, EE and OM, similar to the nutrients of L. chinensis. This supports our contention that the YTBL leaves, stems and MLS are suitable feed for those ruminants requiring high levels of nutrients, such as dairy cows and Boer goats, instead of plant forage, which is decidedly lacking in some parts of the world.
文摘Black locust （Robinia pseudoacacia L.） is one of the most important stand-forming tree species in Hungary and its impor- tance is increasing in many countries. The main aim of the discussed new selection programme is to identify black locust clones with good performance and good form for setting up clonal seed orchards. As a result of selection programme 16 new black locust clones have been improved. In spring 2002 a black locust seed orchard was established with the newly selected clones. About 40% of the plants can be considered to belong to the height growth rate class 1 and 2. Hungary was the first country where micropropagated black locust planting material was used for seed orchard establishment.
