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Effect of Continuous Cropping on Leaf Nutrient and Growth of Different Species of Poplar Plantation 被引量:1
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作者 房莉 余健 陈金林 《Agricultural Science & Technology》 CAS 2011年第2期224-227,252,共5页
[Objective]The paper was to study the effect of continuous cropping on leaf nutrient and growth of different species of poplar plantation.[Method] The tree height,diameter at breast height(DBH),volume of different g... [Objective]The paper was to study the effect of continuous cropping on leaf nutrient and growth of different species of poplar plantation.[Method] The tree height,diameter at breast height(DBH),volume of different generations and species of poplar plantation in poplar production area in northern Jiangsu Province,as well as TN,TP and TK content in their leaves were determined through field investigation and indoor experiment.[Result] With the increasing generation,the changes of TN,TP and TK content in the leaves of different ages of two varieties of forest stand were also different.However,with the increasing tree ages,TN,TP and TK contents in leaves showed decrease trend.With the increasing generation,the changes of tree height of I-69 and I-72 poplar showed the similar trend.The effect of increasing generation on tree height of 7-year-old and 10-year-old poplar was relatively stable,showing decrease trend from generation to generation.The tree height of 4-year-old poplar first increased and then decreased with the increasing generation.The changes of DBH along with different generations were basically consistent with the changes of tree height.With the increasing cultivation generations,the volume of 7-year-old and 10-year-old poplar decreased with significant difference.[Conclusion ] The result provided basis for rational fertilization and management of poplar plantation,improvement of productivity of poplar plantation,and achievement of sustainable management of plantation. 展开更多
关键词 poplar plantation Tree height DBH VOLUME NUTRITION
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Impact of spacing and rotation length on nutrient budgets of poplar plantations for pulpwood 被引量:1
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作者 方升左 徐锡增 +1 位作者 吕士行 唐罗忠 《Journal of Forestry Research》 SCIE CAS CSCD 1999年第3期133-140,共8页
The above-ground biomass and nutrient accumulation by poplar plantations were evaluated for pulpwood production ]n China, Experimental treatments applied in a split-plot design included four planting densities (1111, ... The above-ground biomass and nutrient accumulation by poplar plantations were evaluated for pulpwood production ]n China, Experimental treatments applied in a split-plot design included four planting densities (1111, 833, 625 and 500 stems hm-2), three rotation lengths (4a, 5a and 6a) and three poplar clones (1-69.NL-80351 and 1-72). The highest biomass was achieved in the highest stocked stand (1111 stem hm-2’) at 6 of rotation age for both clone 1-69 and clone 1-72, which is about two times that in the stands of 500 stems hm-2 at 4 ofrotation age. However, the highest occurred in the stand of 833 stems-hm-2 at 6-year rotation for NL-80351. Ranking of the plantation biomass production by component was stem > branches > foliage> stem--bark and the production of the Support components of the plantation was 10-fold that of the productive component, i.e., foliage. Thepattern of accumulation of nutrients by the plantations was similar to the biomass. Nutrient accumulation in theplantations was in the order of Ca>N>K>Mg>P, but some differences existed in annual nutrient accumulationrates for four planting densities and three poplar clones, The mean annual accumulation of N and P in the plantations was 13.2 and 2.8 kg hm-2 in stem, 12.1 and 1 .9 kg hm 2 in branch, and 98.5 and 9.5 kghm’ in foliage. Themean Ca, K and Mg accumulations were 28.2, 1 8.5 and 2.9 kg’hm-2 a-1, 26,9. 11,0 and 2.3 kg-hm-2-a-1 in branch.and 116.5, 81 .3 and 16, 1 kg hm-2 a-1 in foliage, respectively. Biomass utilization standards markedly affected theexport of nutrients from the site, Whole tree utilization yields the most biomass and removes the most nutrients,Removal of stem with 2 10-cm diameter exports about half of the biomass, but N and nutrients removals are only23% and 28% of the total, respectively, Removal of the entire stem provides about tWo--thirds of the total biomassand removes 31,1% total N and 37.5 % total nutrients respectively. Including the branches in the removal increases biomass yield to 92% of the total, and nutrient removal is about 68% of the total, 展开更多
关键词 poplar plantation Biomass productivity NUTRIENT content NUTRIENT ACCUMULATION and removal
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Biochar-Induced Priming Effects in Young and Old Poplar Plantation Soils 被引量:3
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作者 Weiwei Lu Yirui Zhang +7 位作者 Yixian Yao Yuying Wu Han Y.H.Chen Hailin Zhang Jia Yu Caiqin Shen Qi Liu Honghua Ruan 《Phyton-International Journal of Experimental Botany》 SCIE 2020年第1期13-26,共14页
The priming effect(PE)induced by biochar provides a basis for evaluating its carbon(C)sequestration potential in soils.A 60 days’laboratory incubation was conducted,which involved the amendment of biochar(1%of soil m... The priming effect(PE)induced by biochar provides a basis for evaluating its carbon(C)sequestration potential in soils.A 60 days’laboratory incubation was conducted,which involved the amendment of biochar(1%of soil mass)produced from rice straw at 300℃(B300)and 500℃(B500)to young(Y)and old(O)poplar plantation soils,with the aim of studying the responses of biochar-induced PEs to poplar plantation ages.This incubation included six treatments:Y+CK(control),Y+B300,Y+B500,O+CK,O+B300,and O+B500.Carbon dioxide(CO_(2))emissions were significantly increased(p<0.05)in the B300 amended soils,while it was decreased in the B500 amended soils compared to the CK.The primed CO_(2) emissions were 2.35 times higher in the Y+B300 than the O+B300 treatments,which was measured to be 18.6 and 5.56 mg C·kg^(-1) with relative PEs of 12.4%and 3.35%,respectively.However,there was little difference between the primed CO_(2) emissions in Y+B500 and O+B500 treatments,which were measured to be-24.9 and-29.6 mg·C·kg^(-1) with relative PEs of-16.6%and-17.8%,respectively.Dissolved organic carbon(DOC)was significantly lower in the young poplar plantation soil than that in the old poplar plantation soil regardless of biochar amendment throughout the incubation,indicating greater C-limit of soil microorganisms in the young poplar plantation soil.Using ^(13)C isotope tracing,neither B300 nor B500 decreased native soil-derived DOC,which indicated that the negative B500-induced PEs were not due to a reduction in the availability of native soil-derived C.In conclusion,the response of biochar-induced PEs to poplar plantation age depends on biochar types while soil available C indirectly affects biochar-induced PEs.Further studies should focus on how the interactive effects between soil C availability and microbial community impacts biochar-induced PEs. 展开更多
关键词 BIOCHAR dissolved organic carbon pyrolysis temperature poplar plantation age priming effect
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Biomass Production of Poplar Plantation Ecosystem in Yangtze River Beach Land
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作者 Jianfeng ZHANG Qixiang SUN +2 位作者 Jinxing ZHOU Qihua SHAN Lixun WU 《Energy and Power Engineering》 2009年第2期81-84,共4页
Currently, China is home to more than four million hectares of oil plants nationwide, and 154 kinds of energy trees could produce seeds containing more than 40 percent of oil, with total production of the seeds totali... Currently, China is home to more than four million hectares of oil plants nationwide, and 154 kinds of energy trees could produce seeds containing more than 40 percent of oil, with total production of the seeds totaling five million tons. Another 57 million hectares of waste land are available and suitable for planting trees for the production of forest-based bioenergy, of which there is 630,000 hm2 beach land in the middle and lower reaches of Yangtze River where is suited for poplar growing. In order to approach the potential of poplar biomass production, the test was conducted in the paper. The result indicated that in the poplar forest ecosystem the herbaceous biomass production was 15.554 t/hm2. While biomass production for trees was 43.164 t/hm2, totally in the poplar plantation ecosystem biomass production reached 58.718 t/hm2. As well, poplars growing added incomes for local farmers. 展开更多
关键词 biomass production poplar plantation YANGTZE River
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Quantitative study of poplar plantations in three Iranian provinces
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作者 Majid AZIZI Mohammad Mehdi FAEZIPOUR +1 位作者 Ali BAYATKASHKOOLI Fatemeh TAHERI 《Forestry Studies in China》 CAS 2013年第4期363-369,共7页
Fast growing poplar species enjoy a highly favored position in Iran’s forest product industries. However, information on poplar plantations, such as areas, growing stock and harvest volumes, are largely obtained by n... Fast growing poplar species enjoy a highly favored position in Iran’s forest product industries. However, information on poplar plantations, such as areas, growing stock and harvest volumes, are largely obtained by non scientific means and poorly executed methods. A few studies have been conducted to obtain data on the capacity of poplar plantations, their extent, existing growing stock, distribution and species choice in three provinces, i.e., Western Azerbaijan, Kurdistan and Hamedan, with relatively well developed management systems. We opted for a cluster method, a standard sampling method for conducting similar investigations, consisting of two phases. In the first phase we collected library information and conducted half-open interviews with villagers. In the second phase field measurements in the villages of these three provinces were carried out. Information from field measurements on growing stock, cultivated areas, dominant species were used to estimate volumes by way of volume and weight tables. Results obtained from the present study indicate that the average annual volume of timber harvested in the three provinces was 697,723 m3, with an average sampling error of 22.7 per cent. This annual volume of poplar timber harvested from the three provinces was estimated to amount to about 25 per cent of overall harvest; at that rate, the overall annual utilization potential of poplar plantations will be 10 million m3, which constitutes a reliable resource of raw timber for use in wood and paper industries. 展开更多
关键词 poplar plantations field measurements harvest volumes cluster sampling
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Agroforestry, Rural Populations, Poplar Plantations and Marketing
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作者 A.S. Christodoulou 《Journal of Environmental Science and Engineering》 2011年第1期71-77,共7页
One of the objectives of the 1257/99 EU regulation was that rural populations should be able to gain an extra income. This regulation may not be any longer in force, but soon a new one will replace it. The plantations... One of the objectives of the 1257/99 EU regulation was that rural populations should be able to gain an extra income. This regulation may not be any longer in force, but soon a new one will replace it. The plantations that are created by Greek farmers more specifically the plantations of poplar trees-have a ten-year rotation at least. This means that the time between the establishment of the plantation and the harvest is high. As a consequence, during this time, the market environment (e.g. prices) may face substantial changes. Frequently, these changes are so immense that producers are driven in economic distress. This situation is also linked to the domestic timber supply and imports, and as a result to the product prices. Concerning the market prices of poplar trees, one additional factor that has probably deteriorated the situation is the E.U. expansion. This paper examines a case study in North Greece. Vital conclusions are made which may be useful for the Greek and E.U. decision makers regarding the process of dealing with current issues such as the 1257/99 regulation replacement (1698/2005). 展开更多
关键词 ENVIRONMENT AFFORESTATION poplar plantations timber MARKETING
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A New Multistep Approach to Identify Leaf-Off Poplar Plantations Using Airborne Imagery
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作者 Ramzan Ali Khorrami Zahra Naeimi +2 位作者 Michael Wing Hossein Ahani Sayed M. Bateni 《Journal of Geographic Information System》 2022年第6期634-651,共18页
Identification of type of leafless trees using both fall imagery and field-based surveys is a global concern in the forest science community. Few studies were devoted to separate leafless trees from others in the grow... Identification of type of leafless trees using both fall imagery and field-based surveys is a global concern in the forest science community. Few studies were devoted to separate leafless trees from others in the growth season using remote sensing imagery. But this study was the first attempt to identify the type of leafless tree in the fall imagery. We investigated the potential of the Simple Linear Iterative Clustering (SLIC) and k-mean segmentation techniques, and texture and color image analyses to identify leafless poplar trees using imagery collected in a leaf-off season. For the first time in this study, the star shaped feature identifier was found through a binary image that was successful in identifying leaf-off poplar plantations. Optimal threshold values of Normalized Difference Vegetation Index (NDVI) and Normalized Green Index (NGI) indices were able to differentiate highly vegetated land, green farms, and gardens from the grasses that sometimes grow between poplar plantation lines. A Coefficient of Variation (CV) of red color intensity and histogram of value were also successful in separating bare soil and other land cover types. Imagery was processed and analyzed in a Matlab software. In this study, leafless poplar plantation was identified with a user accuracy of 84% and the overall accuracy was obtained 81.3%. This method provides a framework for identification of leafless poplar trees that may be beneficial for distinguishing other types of leafless trees. 展开更多
关键词 Leafless poplar plantations Fall Ultracam Imagery Star Shaped-Feature K-Mean Segmentation Texture and Color Image Analysis
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Exploring the factors affecting carbon and nutrient concentrations in tree biomass components in natural forests,forest plantations and short rotation forestry 被引量:4
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作者 Roque Rodriguez-Soalleiro Cristina Eimil-Fraga +6 位作者 Esteban Gomez-Garda Juan Daniel Garcia-Villabrille Alberto Rojo-Alboreca Fernando Munoz Nerea Oliveira Hortensia Sixto Cesar Perez-Cruzado 《Forest Ecosystems》 SCIE CSCD 2018年第4期498-515,共18页
Background: Coupling biomass models with nutrient concentrations can provide sound estimations of carbon and nutrient contents, enabling the improvement of carbon and nutrient balance in forest ecosystems. Although nu... Background: Coupling biomass models with nutrient concentrations can provide sound estimations of carbon and nutrient contents, enabling the improvement of carbon and nutrient balance in forest ecosystems. Although nutrient concentrations are often assumed to be constant for some species and specific tree components, at least in mature stands,the concentrations usually vary with age, site index and even with tree density. The main objective of this study was to evaluate the sources of variation in nutrient concentrations in biomass compartments usually removed during harvesting operations, covering a range of species and management conditions: semi-natural forest, conventional forest plantations and short rotation forestry(SRF). Five species(Betula pubescens, Quercus robur, Eucalyptus globulus, Eucalyptus nitens and Populus spp.) and 14 genotypes were considered. A total of 430 trees were sampled in 61 plots to obtain 6 biomass components:leaves, twigs, thin branches, thick branches, bark and wood. Aboveground leafless biomass was pooled together forpoplar.The concentrations of C, N, K, P, Ca, Mg, S, Fe, Mn, Cu, Zn and B were measured and the total biomass of each sampled tree and plot were determined. The data were analysed using boosted regression trees and conventional techniques.Results: The main sources of variation in nutrient concentrations were biomass component > > genotype(species) ≈ age >tree diameter. The concentrations of Ca, Mg and K were most strongly affected by genotype and age. The concentrations of P, K, Ca, Mg, S and Cu in the wood component decreased with age, whereas C concentrations increased, with a trend to reach 50% in the older trees. In the SRF, interamerican poplar and P. trichocarpa genotypes were comparatively more efficient in terms of Ca and K nutrient assimilation index(NAI)(+65-85%) than eucalypts, mainly because leafless biomass can be removed. In the conventional eucalypt plantations(rotation 15 years), debarking the wood at logging(savings of225% of Ca and 254% of Mg for E. globulus) or the use of selected genotypes(savings of 45% of P and 35% of Ca) will provide wood at a relatively lower nutrient cost. Considering all the E. globulus genotypes together, the management for pulp with removal of debarked wood shows NAI values well above(x 1.7-x 3.9) the ones found for poplar or eucalypt SRF and also higher(x 1.6-x4.0) than the ones found for oak and birch managed in medium or long rotations.The annual rates of nutrient removal were low in the native broadleaved species but the rates of available soil nutrients removed were high as compared to poplar or eucalypts. Management of native broadleaved species should consider nutrient stability through selection of the biomass compartments removed.(Continued on next page)(Continued from previous page)Conclusions: The nutrient assimilation index is higher in poplar grown under short rotation forestry management than in the other systems considered. Nutrient management of fast growing eucalyptus plantations could be improved by selecting efficient genotypes and limiting removal of wood. The values of the nutrient assimilation index are lower in the natural stands of native broadleaved species than in the other systems considered. 展开更多
关键词 Nutrient removal Biomass crops poplar genotypes Eucolyptus OAK BIRCH plantation sustainability
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A Global Analysis of Temperature Effects on Populus Plantation Production Potential 被引量:2
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作者 Natalya K. Kutsokon Shibu Jose Eric Holzmueller 《American Journal of Plant Sciences》 2015年第1期23-33,共11页
The genus Populus contains some of the most economically important tree species and hybrids in the world. We compared productivity of short and long-rotation poplar plantations using published data from 23 countries t... The genus Populus contains some of the most economically important tree species and hybrids in the world. We compared productivity of short and long-rotation poplar plantations using published data from 23 countries to determine if climate, particularly temperature, had any effect on the observed patterns of productivity. We discovered that climate factors (related to temperature) and clone origin (pure species or hybrids) slightly influenced productivity of long rotation forests more than short rotation plantations. While long rotation plantation productivity exhibited positive correlations with increasing temperature during winter and decreasing heat during summer, short rotation plantations showed weak positive relationship among productivity and increasing yearly temperature and the number of hot days. It was apparent that short rotation plantations productivity was less dependent on regional climatic variables or origin of clone. However, it appears that overall, regardless of the system, Populus species are generally adapted to a range of climatic conditions where they are planted. 展开更多
关键词 poplar POPULUS sp. HYBRIDS FAST-GROWING plantations Intensive FORESTRY Short and Long Rotation plantations Stem Volume Climate
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Natural Resistance of Two Plantation Woods Populus × canadensis cv. and Cunninghamia lanceolata to Decay Fungi and Termites
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作者 XingJia-qi MomoharaIkuo OhmuraWakako 《Forestry Studies in China》 CAS 2005年第1期36-39,共4页
Natural durability of two plantation woods, Chinese fir and I-214 poplar, was investigated thoroughly by three test- ing methods, namely an accelerated laboratory decay test, a fungus cellar test and a field test. Af... Natural durability of two plantation woods, Chinese fir and I-214 poplar, was investigated thoroughly by three test- ing methods, namely an accelerated laboratory decay test, a fungus cellar test and a field test. After the decay test using Postia pla- centa and Trametes versicolor, Chinese fir and the I-214 poplar showed 34% and 69% of mass loss, respectively, indicating they should be classified as slightly durable and non-durable wood. This conclusion was confirmed by the fungus cellar test and the field test. Like the performance in the decay test, I-214 poplar showed no resistance to termites either in the laboratory or in the field, whereas Chinese fir would be classified as moderately resistant. 展开更多
关键词 plantation Chinese fir plantation I-214 poplar natural resistance to decay fungi and termites
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Evaluation of soil nutrient status in poplar forest soil by soil nutrient systematic approach 被引量:5
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作者 余常兵 陈防 +1 位作者 罗治建 陈卫文 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期298-300,共3页
A study was conducted to evaluate the soil nutrient status of poplar plantation by Soil Nutrient Systematic Approach (SNSA) in Jianghan Plain, Hubei Province, China. Soil physiochemical properties were analyzed in lab... A study was conducted to evaluate the soil nutrient status of poplar plantation by Soil Nutrient Systematic Approach (SNSA) in Jianghan Plain, Hubei Province, China. Soil physiochemical properties were analyzed in laboratory through collection soil samples of study site. Ten treatments of application different fertilizers were designed such as CK, optimum treatment (N, P, K, Zn), N(P, K, Zn), P(N, K, Zn), K(N, P, Zn), +Mg(N, P, K, Zn, Mg), Zn (N,P,K), +2P(N, 2P, K, Zn), +2K(N, P, 2K, Zn), and 2N+2P+2K(2N, 2P, 2K, Zn) for field experiment to test the effect on tree height, diameter (DBH) growth, and dry weight of poplar. The results showed that there was no significant difference in tree heights between treatments with different fertilizers, diameter growth of poplar trees in treatments of lack of N and Zn was significantly slower than that of trees in optimum treatment, and dry weight of poplar dropped significantly for treatment of CK as well as treatments without application N and Zn. It is concluded that N and Zn were main limiting factor for poplar growth. Results from laboratory analysis and field experiment were uniform per-fectly, which proved that SNSA was reliable in evaluating soil nutrient status of poplar plantation. 展开更多
关键词 Soil nutrient status Soil Nutrient Systematic Approach poplar plantation Limiting factor Evaluation method Soil physiochemical properties
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杨树人工林复合经营模式对土壤N_(2)O与CO_(2)排放的影响
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作者 宋子琪 李野 +2 位作者 丁思惠 田野 方升佐 《生态科学》 CSCD 北大核心 2024年第1期105-112,共8页
为探讨杨树人工林复合经营模式对土壤温室气体排放的影响,基于11年生“南林-895杨”(Populus×euramericana‘Nanlin-895’)人工林,设置纯林、林下种植麦冬(Ophiopogon japonicas)和林下养鸡3种复合经营模式,采用静态箱-气相色谱法... 为探讨杨树人工林复合经营模式对土壤温室气体排放的影响,基于11年生“南林-895杨”(Populus×euramericana‘Nanlin-895’)人工林,设置纯林、林下种植麦冬(Ophiopogon japonicas)和林下养鸡3种复合经营模式,采用静态箱-气相色谱法每月测定土壤N_(2)O和CO_(2)排放通量,同时测定土壤温湿度,分析复合经营模式对土壤N_(2)O和CO_(2)排放和产量的影响及与相关影响因子的关系。结果表明:不同复合经营模式林下土壤温、湿度存在显著差异;不同杨树复合经营模式间,土壤N_(2)O和CO_(2)排放速率动态变化与年累积排放量存在显著差异,杨树林下种植麦冬的土壤N_(2)O年累积排放量最高,为233.47 mg·m^(-2)·a^(-1),而林下养鸡的土壤CO_(2)年累积排放量最高,达2328.87 g·m^(-2)·a^(-1)。总体来看,不同复合经营模式林地土壤温室气体(N_(2)O和CO_(2))年累积排放量为林下养鸡>林下种植麦冬>杨树纯林;土壤温、湿度对土壤CO_(2)和N_(2)O排放速率有显著影响,其中,土壤CO_(2)排放速率与土壤温度之间呈显著线型相关,而与土壤湿度呈现抛物线型关系;土壤N_(2)O排放速率与土壤温、湿度的关系均可用抛物线型关系来描述。综上所述,不同杨树复合经营模式改变了林地土壤的温、湿度,进而对温室气体排放产生了显著的影响。从1年的研究结果看,种植麦冬和养鸡的杨树人工林林地土壤温室气体的年累积排放量高于纯林,表明林农复合经营增加了土壤温室气体的排放。 展开更多
关键词 杨树人工林 气候变化 静态箱法 林农复合经营 温室气体
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散射辐射比例对华北平原杨树人工林生态系统能量分配的影响
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作者 徐磊 吴小云 +4 位作者 律江 石云 朱梦洵 许行 张志强 《林业科学》 EI CAS CSCD 北大核心 2024年第3期100-110,共11页
【目的】在全球辐射总量及其组成显著变化的背景下,明确散射辐射比例(F_(dif))对华北平原杨树人工林生态系统能量分配的影响,为准确评估杨树人工林的生态服务功能和进一步完善生态系统过程模型提供科学依据。【方法】利用涡度相关技术... 【目的】在全球辐射总量及其组成显著变化的背景下,明确散射辐射比例(F_(dif))对华北平原杨树人工林生态系统能量分配的影响,为准确评估杨树人工林的生态服务功能和进一步完善生态系统过程模型提供科学依据。【方法】利用涡度相关技术和小气候观测,对2019、2021年生长季(DOY 91~304)杨树人工林生态系统的能量通量和环境因子开展研究。【结果】华北平原杨树人工林生态系统能量分配在生长季中期(DOY 152~243)以潜热通量(LE)为主,在生长季初期(DOY 91~151)和末期(DOY 244~304)以显热通量(H)为主。F_(dif)与波文比(β)呈显著负相关(P<0.01),与冠层导度(G_(s);P<0.01)、冠层分离指数(Ω;P<0.05)和Priestley-Taylor系数(α;P<0.01)呈显著正相关。通径分析结果表明,Gs是调节华北平原杨树人工林生态系统能量分配的主要因子,F_(dif)下降时,Gs降低,饱和水汽压差(VPD)增大,生态系统的β显著增大,进而改变生态系统能量分配模式。【结论】F_(dif)变化影响华北平原杨树人工林生态系统能量分配,F_(dif)下降会导致能量平衡中的LE所占比例增加、H所占比例相应减小。在气候变化背景下,本研究不仅可深入揭示华北平原杨树人工林生态系统能量分配机制,同时也对准确评估森林生态系统服务功能起到至关重要的作用。 展开更多
关键词 散射辐射 杨树人工林 能量分配 通径分析 华北平原
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长期氮添加对苏北杨树人工林碳储量的影响
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作者 安宇超 顾宇晨 +1 位作者 张茜 王国兵 《水土保持研究》 CSCD 北大核心 2024年第2期27-32,42,共7页
[目的]量化分析氮添加对南方杨树人工林碳储量分配格局的影响,为进一步提升我国杨树人工林在实现“双碳”战略目标中的作用,进而为我国“双碳”战略新时代背景下杨树人工林生产经营模式优化及技术集成提供理论支撑。[方法]基于东台林场... [目的]量化分析氮添加对南方杨树人工林碳储量分配格局的影响,为进一步提升我国杨树人工林在实现“双碳”战略目标中的作用,进而为我国“双碳”战略新时代背景下杨树人工林生产经营模式优化及技术集成提供理论支撑。[方法]基于东台林场杨树人工林长期氮添加样地,采用随机区组设置5个不同浓度氮处理:N_(0)〔0 g/(m^(2)·a)〕、N_(1)〔5 g/(m^(2)·a)〕、N_(2)〔10 g/(m^(2)·a)〕、N_(3)〔15 g/(m^(2)·a)〕、N_(4)〔30 g/(m^(2)·a)〕,研究长期氮添加对杨树人工林乔木层、土壤层、凋落物层、林下植被层碳储量的影响。[结果](1)与对照相比,杨树人工林乔木层碳储量在N_(3),N_(4)处理下显著增加,在N_(3)处理下最为显著,提高了21.6%;(2)各处理均显著提高了0—15 cm土层的土壤碳储量,但对30—45 cm土层的土壤碳储量没有显著影响;(3)N_(2),N_(3),N_(4)对凋落物层碳储量影响显著,N_(3)对其影响最强,提高了49.7%;各处理均降低了林下植被层碳储量,但差异不显著;(4)相关性分析结果表明:杨树人工林各层碳储量与土壤中TN,MBN,DON,DOC呈正相关,与pH,C/N呈负相关。[结论]在N_(3)处理下,即15 g/(m^(2)·a)对东台杨树人工林碳储量的影响最大,有利于其生态系统碳储量快速且稳定积累。 展开更多
关键词 碳储量 氮添加 杨树人工林 苏北沿海地区
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The influences of biotic and abiotic factors on the occurrence and severity of poplar canker disease in Qingfeng County, China and the management implications 被引量:3
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作者 Zhigang Ma Jingle Zhu +5 位作者 Zhiqiang Sun Jun Liang Zhaoxin Zhang Limin Zhang Lijuan Sun Wenjuan Li 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第4期1025-1034,共10页
Landscape pathology is a research approach that can provide validation of the effectiveness of regional controls of forest disease at a landscape scale. In this paper, we analyzed the effects of stand features, manage... Landscape pathology is a research approach that can provide validation of the effectiveness of regional controls of forest disease at a landscape scale. In this paper, we analyzed the effects of stand features, management approaches, and geographical locations on poplar canker disease incidence (DI) and disease severity index (DSI) of individual trees at a 10 km x 10 km mesoscale landscape in Qingfeng County, China. DI varied significantly with stand age, tree densities, and the degree of canopy closure. DI in stands younger than 4 years old was significantly lower than that in the stands over 6 years old and reached the highest value at a stand age of 8-10 years. Overall, DI was positively correlated with stand age, stand density, andthe degree of canopy closure. DI was significantly lower in agro-forest stand patches than in other three patch types, i.e. isolated patch, pure stand patch, and mixed stand patch. Poplar plantations distributed around and near to villages exhibited significantly higher DI mainly due to human activities and herbivores. Fragmentation or connectivity in this mesoscale landscape seemed not impact disease occurrence. DSI was not significantly correlated with stand density, but varied significantly with tree varieties and trees ages. DSI was highest in stands of 10-12 year trees for all poplar varieties we studied here. Plantation density and plantation age were thus critical factors in determining DI and DSI. A logistic predictive model of disease occurrence was developed for the study area, considering varieties, age, height, density, canopy cover, stand types, patch types, management status, and stand geographical locations. Our study here shows that adjustment of stand density by thinning at different plantation ages is an effective approach controlling the occurrence canker disease in short-rotation poplar plantations at the landscape scale. 展开更多
关键词 Landscape pathology poplar plantation Canker disease - Disease incidence - Disease severityincidence - Stand features Adaptation
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Photosynthetic response of poplar leaves at different developmental phases to environmental factors 被引量:1
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作者 Qingqing Wu Yang Liu +1 位作者 Shengzuo Fang Pingping Li 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第5期909-916,共8页
With economic incentives and interests in fast-growing poplar trees for short-rotation production of fiber and veneer, many new poplar hybrids have been bred and planted in China, but how to match the new poplar clone... With economic incentives and interests in fast-growing poplar trees for short-rotation production of fiber and veneer, many new poplar hybrids have been bred and planted in China, but how to match the new poplar clones to suitable sites and maintain their higher growth rates is still not very clear. In this study, the photosynthetic response of poplar leaves at various developmental stages during two seasons (summer and autumn) was explored and mechanistic models for the photosynthesis of poplar leaves at different developmental phases in response photosynthetic active radiation (PAR), temperature, and relatively humidity were established using the optimization software package 1st Opt. Mature poplar leaves in autumn had significantly higher photosynthetic capacity than leaves at other stages and seasons. Based on the models established for poplar leaves at different phases, the main limiting factors for photosynthesis at the research site were high PAR and temperature in the summer and low PAR in the autumn. Our results highlight the importance of selecting suitable sites, pruning and stand density control during the plantation development to maintain higher photosynthetic rates of poplar trees and to establish optimum cultivation patterns for various utilization of poplar plantations. 展开更多
关键词 Leaf development MODEL PHOTOSYNTHESIS poplar plantation
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Seedling test and genetic analysis of white poplar hybrid clones
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作者 LI Bo HANG Xi-bing +3 位作者 ZHANG You-hui ZHANG Zhi-yi LI Shan-wen AN Xin-min 《Forestry Studies in China》 CAS 2008年第3期149-152,共4页
Cross breeding strategies are very efficient for gaining new and superior genotypes. Ninety-eight new white poplar hybrid clones produced from 12 cross combinations within the Section Leuce Duby were studied using gen... Cross breeding strategies are very efficient for gaining new and superior genotypes. Ninety-eight new white poplar hybrid clones produced from 12 cross combinations within the Section Leuce Duby were studied using genetic analysis and seedling tests. We exploited the wide variation that exists in this population and found that the differences among diameter at breast height (DBH), root collar diameter (RCD) and height (H) were statistically extremely significant. The repeatability of clones of these measured traits ranged from 0.947-0.967, which indicated that these traits were strongly controlled by genetic factors. Based on multiple compari- sons, a total of 25 clones showed better performance in growth than the control cultivar. These 25 clones were from six different cross combinations, which can guarantee a larger genetic background for future new clone promotion projects. This study provides a simple overview on these clones and can guide us to carry out subsequent selection plans. 展开更多
关键词 white poplar multi-clonal plantation seedling test genetic analysis
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毛乌素沙地杨树人工林林下植物群落特征 被引量:4
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作者 胡尔查 王晓江 +6 位作者 王铮 李梓豪 洪光宇 李卓凡 杨海峰 高孝威 赵学军 《林业科学研究》 CSCD 北大核心 2023年第5期189-197,共9页
[目的]研究人工林林下植物群落特征及其与林分因子的关系,对沙地植被恢复成效的评价和人工林管理具有重要意义。[方法]本研究以毛乌素沙地杨树人工林群落为研究对象,调查研究林下植物群落特征,并重点探讨了林分郁闭度、密度等林分因子... [目的]研究人工林林下植物群落特征及其与林分因子的关系,对沙地植被恢复成效的评价和人工林管理具有重要意义。[方法]本研究以毛乌素沙地杨树人工林群落为研究对象,调查研究林下植物群落特征,并重点探讨了林分郁闭度、密度等林分因子对林下植被的影响。[结果]研究区杨树人工林林下共发现植物32种,隶属于12科28属,其中豆科、禾本科、菊科植物最多,占总植物种的62.51%;林下草本植物生活型以多年生草本植物为主,占总物种的78.13%,植物水分生态类型以旱生、中旱生植物为主,占总物种数的75.00%,其次为旱中生和中生植物;林下草本层Margalef丰富度指数变化范围为1.20~3.17,Simpson优势度指数变化范围为0.48~0.88,Shannon-Wiener多样性指数变化范围为0.95~2.34,Pielou均匀度指数变化范围为0.16~0.48,林龄32年生时林下物种多样性最高;结构方程模型结果显示林分郁闭度和密度与林下灌木层盖度之间存在负效应关系,人工林郁闭度较高时,林下无灌木层形成。林分郁闭度的增加有利于草本层的发育,而林分密度与草本层盖度、地上生物量、物种丰富度和Shannon-Wiener多样性指数之间存在负效应关系,灌木层对草本层的影响与乔木层相似。[结论]毛乌素沙地杨树人工林林下草本植物多样性较高,灌木种类较少,其大小受郁闭度和密度等林分因子的影响较明显。适当调控林分密度和结构,将有利于毛乌素沙地杨树人工林林下物种多样性的维持和近自然改造。 展开更多
关键词 杨树人工林 林分因子 林下植被 物种多样性 毛乌素沙地
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Effects of Poplar Plantations on the Physical and Chemical Properties of Soils:A Case Study in the North China Plain
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作者 王佳月 辛良杰 《Journal of Resources and Ecology》 CSCD 2016年第5期352-359,共8页
In recent years, large areas of farmland in the North China Plain have been converted into short-rotation poplar plantations. To analyze the impacts of poplar plantations on soil, 22 soil samples were collected and as... In recent years, large areas of farmland in the North China Plain have been converted into short-rotation poplar plantations. To analyze the impacts of poplar plantations on soil, 22 soil samples were collected and assayed from the soil profiles of a corn field and a poplar plantation. The results showed that the average soil moisture content of the soil profile in the poplar field was 2.6 percent lower than that of the arable land. The maximum dif- ference in soil moisture content was found in the upper 0-10 cm of topsoil. Soil organic matter and nitrogen, phosphorus and potassium in the cornfield were significantly higher than in the poplar field. Higher nutrient content in the corn field may result from higher fertilizer inputs and the practice of returning straw to the cropped field. The analysis also showed no significant increase in soil organic matter content in deeper soil layers of the poplar field, which means that the conditions are not favorable for the formation of soil organic matter, or that soil organic matter needs a longer time to develop. Elements such as magnesium, iron, manganese and copper in both the corn field and the poplar field had a tendency to accumulate with increasing soil depth. Magnesium, iron, manganese and copper in the 0-80 cm soil layer of the poplar field were higher than those of the cornfield, but the situation was reversed at depths greater than 80 cm. It is concluded that poplar trees consume a large amount of soil moisture and soil nutrients. Local governments should prevent the development of new plantations of fast-growing trees in farmland and help farmers to recover their farmland from forestry plantations. 展开更多
关键词 poplar plantations North China Plain soil physical properties soil chemical properties
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MUG生物质树脂/硅酸钠木材改性剂的优化制备 被引量:7
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作者 杜浩佳 吕文华 +2 位作者 孔静 刘强强 柴宇博 《西北农林科技大学学报(自然科学版)》 CSCD 北大核心 2023年第1期102-109,共8页
【目的】通过优化葡萄糖/三聚氰胺/尿素树脂(MUG)的葡萄糖配比及MUG树脂与硅酸钠的配比,减少二氧化硅及葡萄糖羟基残留,以改善改性材吸湿、尺寸不稳定等问题。【方法】设置葡萄糖、三聚氰胺、尿素物质的量比为m∶1∶4(m分别为2,4,6,8,10... 【目的】通过优化葡萄糖/三聚氰胺/尿素树脂(MUG)的葡萄糖配比及MUG树脂与硅酸钠的配比,减少二氧化硅及葡萄糖羟基残留,以改善改性材吸湿、尺寸不稳定等问题。【方法】设置葡萄糖、三聚氰胺、尿素物质的量比为m∶1∶4(m分别为2,4,6,8,10和12),根据红外解析树脂预聚程度,测定树脂黏度、固含量和水溶倍数等性能,筛选出优化MUG树脂的葡萄糖配比;将优化制备的MUG树脂与硅酸钠复配得5种改性剂:G_(5)S_(25)、G_(10)S_(20)、G_(15)S_(15)、G_(20)S_(10)、G_(25)S_(5)(G代表MUG树脂,S代表硅酸钠,下标数值代表其在改性剂中的质量分数),通过测定改性材黏度、pH值和改性材的密度、增重率、吸水率、尺寸稳定性、力学性能,优化MUG树脂与硅酸钠的复合配比。【结果】①随着葡萄糖增加,MUG树脂的黏度、固含量增大,水溶性好,储存更稳定。②红外分析表明,随着葡萄糖增加,MUG树脂在1667 cm^(-1)处的酰胺羰基峰、在1630 cm^(-1)处的酰胺N-H键弯曲振动峰均变小,在1552和1421 cm^(-1)处的亚氨基树脂特征峰、在770 cm^(-1)处的呋喃环特征峰均增强;当葡萄糖物质的量比增大至8以上时,上述吸收峰强度无明显变化,故葡萄糖物质的量比宜为8。③随着树脂含量增加,MUG树脂/硅酸钠改性剂的黏度增大、pH值降低,G_(25)S_(5)改性剂不稳定、易产生沉淀。④各组改性材中,以G_(20)S_(10)改性材的增重率最大、吸水率最低,径向、弦向、体积湿胀率最低;与素材相比,其密度提高了60.9%,浸水144 h时的吸水率下降35.4%;其径向、弦向、体积抗湿胀率分别为60.81%,34.20%和51.87%,抗弯弹性模量、抗弯强度和顺纹抗压强度均比素材明显提高。【结论】MUG树脂能有效抑制硅酸钠引起的吸湿和皱缩,二者的优化复配比例为质量分数20%树脂和质量分数10%硅酸钠。 展开更多
关键词 人工林杨木 木材改性剂 葡萄糖/三聚氰胺/尿素生物质树脂 改性材性能
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