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1.
Split fertilizer application affects growth, biomass allocation, and fertilizer uptake efficiency of hybrid Eucalyptus 总被引:1,自引:0,他引:1
Shucai Zeng Douglass F. Jacobs Joshua L. Sloan Li Xue Yin Li Shuangshuang Chu 《New Forests》2013,44(5):703-718
Fertilization is indispensable to the establishment success of many eucalypt plantations. Split application of fertilizer has proven effective in agronomic systems; however, its potential impact on eucalypt tree growth and fertilizer uptake efficiency (FUE) is not well understood. This study investigated the effects of split fertilizer applications on seedling growth and biomass production, nutrient uptake, and FUE for the Guanglin No. 9 clone [hybrid of Eucalyptus grandis (Hill ex Maiden) × Eucalyptus urophylla S.T. Blake]. Three application timings and a control were established at rates of 125 and 250 g inorganic fertilizer (16N–7P–7K) per seedling. Split application played a more pronounced role than fertilization rate in eucalypt seedling growth and biomass accumulation. Compared to a single-time application, split applications increased eucalypt seedling height and root collar diameter growth, biomass, and nutrient uptake. The ratio of root to seedling dry mass showed a decreasing trend with split applications, whereas ratios of stem and branch to seedling dry mass tended to increase with split applications. Split applications also significantly improved FUE compared to the single-time application treatment. Findings of this study suggest that split applications of inorganic fertilizer with two application times could be an appropriate fertilization method to improve seedling growth and FUE of this eucalypt clone. 相似文献
2.
Many textural measures have been developed and used for improving land cover classification accuracy, but they rarely examined
the role of textures in improving the performance of forest aboveground biomass estimations. The relationship between texture
and biomass is poorly understood. In this paper, SPOT5 HRG datasets were ortho-rectified and atmospherically calibrated. Then
the transform of spectral features is introduced, and the extraction of textural measures based on the Gray Level Co-occurrence
Matrix is also implemented in accordance with four different directions (0°, 45°, 90° and 135°) and various moving window
sizes, ranging from 3 × 3 to 51 × 51. Thus, a variety of textures were generated. Combined with derived topographic features,
the forest aboveground biomass estimation models for five predominant forest types in the scenic spot of the Mausoleum of
Sun Yat-Sen, Nanjing, are identified and constructed, and the estimation accuracies exhibited by these models are also validated
and evaluated respectively. The results indicate that: 1) Most textures are weakly correlated with forest biomass, but minority
textural measures such as ME, CR and VA play a significantly effective and critical role in estimating forest biomass; 2)
The textures of coniferous forest appear preferable to those of broad-leaved forest and mixed forest in representing the spatial
configurations of forests; and 3) Among the topographic features including slope, aspect and elevation, aspect has the lowest
correlation with the biomass of a forest in this study.
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Translated from Remote Sensing Information, 2006, 6: 6–9 [译自: 遥感信息] 相似文献
3.
An approach to simplify the prediction of average aboveground forest biomass values and their associated variability is presented in this study. The advantage of the proposed approach is based on the fact that it can be applied to any form of equation describing tree size–shape relationships and to any tree species. The proposed approach was tested against a tree-level dataset comprising of 1211 pairs of aboveground tree biomass (M) and tree diameter (D) values. The compiled trees were grouped into several D classes and average M estimates (μM) with their associated variances (σM) were predicted for each class based on second-order Taylor expansion formulas. Nineteen beech (Fagus moesiaca Cz.) plots were also used to derive μM and σM estimates on an area basis in order to test the applicability of the approach on forest scale. The only assumption made was that the simple allometric model M = aDb can accurately describe the M–D relationship. The results indicated that the mere recording of D distribution and appropriate selection of a and b values may provide very good estimates for μM and σM both at global and forest level. It is therefore concluded that biomass studies related to carbon sequestration, biofuel potential, ecophysiological processes and management practices are considerably simplified. 相似文献
4.
Aaron Smith Aksel Granhus Rasmus Astrup Ole Martin Bollandsås Hans Petersson 《Scandinavian Journal of Forest Research》2014,29(6):565-578
A suite of regional allometric aboveground biomass functions were derived for Betula pubescens and Betula pendula for Norwegian conditions. The data consisted of 67 trees sampled throughout Norway. A total of 14 component functions were developed for total aboveground, total stem, stemwood, stem bark, live crown, live branch, leaf, and dead branch biomass using combinations of diameter at breast height and height as predictor variables. Application of the derived functions to existing local southern Norwegian mountain birch and regional Swedish biomass datasets indicated an overall good predictive ability of the developed functions. However, the functions produced slight underestimates, suggesting that the respective birch populations had differing biomass allocation patterns. When the developed functions were applied to Norwegian National Forest Inventory data, they produced slightly higher biomass stock and stock change estimates than what is obtained using existing Swedish functions. The higher estimates were evident in the north, central, and western part of Norway, while estimates were similar in southeastern Norway where growing conditions are most similar to Swedish conditions. The analysis indicates that the derived functions are the best available for regional birch biomass stock and stock change estimation in Norway. 相似文献
5.
6.
To identify hybrid-specific differences in developmental response to mechanical perturbation (MP), we compared the effects of stem flexure on several morphological and mechanical properties of two Populus trichocarpa Torr. & A. Gray x P. deltoides Bartr. ex Marsh. hybrids, 47-174 and 11-11. In response to the MP treatment, both hybrids exhibited a significant increase in radial growth, especially in the direction of the MP (47-174, P = 0.0001; 11-11, P = 0.002), and a significant decrease in height to diameter growth ratio (P = 0.0001 for both hybrids), suggesting that MP-treated stems are more tapered than control stems. A direct consequence of the MP-induced increase in radial growth was a significant increase in flexural rigidity (EI, N mm(2)) in stems of both hybrids (47-174, P = 0.0001; 11-11, P = 0.009). Both control and MP-treated stems of Hybrid 47-174 had significantly greater height to diameter ratios and EI values than the corresponding stems of Hybrid 11-11 (11-11 stem ratios and EI values were 85 and 76%, respectively, of those of 47-174). In Hybrid 47-174, Young's modulus of elasticity (E, N mm(-2)), a measure of stem flexibility, for MP-treated stems was only 80% of the control value (P = 0.0034), whereas MP had no significant effect on E of stems of Hybrid 11-11 (P = 0.2720). Differences in flexure response between the hybrids suggest that Hybrid 47-174 can produce a stem that is more tolerant of wind-induced flexure by altering both stem allometry and material properties, whereas Hybrid 11-11 relies solely on changes in stem allometry for enhanced stability under MP conditions. 相似文献
7.
《林业研究》2020,31(5)
Biotic and abiotic factors control aboveground biomass(AGB) and the structure of forest ecosystems. This study analyses the variation of AGB and stand structure of evergreen broadleaved forests among six ecoregions of Vietnam. A data set of 173 1-ha plots from 52 locations in undisturbed old-growth forests was developed. The results indicate that basal area and AGB are closely correlatedwith annual precipitation, but not with annual temperature,evaporation or hours of sunshine. Basal area and AGB are positively correlated with trees [ 30 cm DBH. Most areas surveyed(52.6%) in these old-growth forests had AGB of100–200 Mg ha~(-1); 5.2% had AGB of 400–500 Mg ha~(-1),and 0.6% had AGB of [ 800 Mg ha~(-1). Seventy percent of the areas surveyed had stand densities of 300–600 ind.ha~(-1), and 64% had basal areas of 20–40 m~2 ha~(-1). Precipitation is an important factor influencing the AGB of old-growth, evergreen broadleaved forests in Vietnam.Disturbances causing the loss of large-diameter trees(e.g.,[ 100 cm DBH) affects AGB but may not seriously affect stand density. 相似文献
8.
Olfa Shaiek Denis Loustau Pierre Trichet Céline Meredieu Beya Bachtobji Salah Garchi Mohamed Hédi EL Aouni 《Annals of Forest Science》2011,68(3):443-452
• Introduction
In order to predict the biomass of aerial components of maritime pine stands (Pinus pinaster Ait.), generalized allometric equations were developed using data collected from the southern and northern margins of its geographical area. 相似文献9.
Planting stock type and quality can have an important impact on early growth rates of plantations. The goal of this study was to evaluate early growth and root/shoot development of different planting materials in typical heavy clay soils of northwestern Quebec. Using one-year-old bareroot hybrid poplar dormant stock, four planting materials were compared: (1) regular bareroot stock, (2) rootstock (stem pruned before planting), (3) whips (roots pruned before planting), and (4) cuttings (30 cm stem sections taken from the basal portion of bareroot trees, i.e. roots and shoot pruned). Rooted stock types (bareroot and rootstock) produced, on average, 1.2 times larger trees than unrooted stock types (cuttings and whips). However, shoot-pruned stock types (rootstocks and cuttings) reached similar heights and basal diameters as unpruned stock types (bareroots and whips), during the first growing season. Shoot pruning reduced leaf carbon isotopic ratios, suggesting that unpruned stock types were water-stressed during the first growing season. The stress was most likely caused by early leaf development while root growth occurred later in the summer. We conclude that shoot pruning bareroot stock is a useful management option to reduce planting stress without compromising early growth rates of hybrid poplars. 相似文献
10.
Yasumasa Hirata Ryuichi Tabuchi Pipat Patanaponpaiboon Sasitorn Poungparn Reiji Yoneda Yoshimi Fujioka 《Journal of Forest Research》2014,19(1):34-41
Mangroves play important roles in providing a range of ecosystem services, mitigation of strong waves, protection of coastlines against erosion, maintenance of water quality, and carbon sink in the context of global warming. For trees in mangrove forests in southern Ranong Province, Thailand, we investigated the allometric relationship between crown area derived from high-resolution satellite data and stem diameter and used the resulting model to estimate aboveground biomass. We used QuickBird panchromatic and multispectral data acquired for the study area on 15 October 2006 as the high-resolution satellite data. Individual tree crowns were extracted from the satellite image of panchromatic data by using the watershed method, and the species were identified by using the maximum-likelihood method for the multispectral data. Overall classification accuracy for species identification was 88.5 %. The biomass derived from our field survey was plotted against aboveground biomass in the sample plots, estimated from the QuickBird data. The regression line through the origin between the satellite-estimated biomass and biomass based on the field data had a slope of 1.26 (R 2 = 0.65). Stand aboveground biomass estimated from the high-resolution satellite data was underestimated because of a lack of data on the biomass of suppressed trees and inappropriate segmentation of crowns of large trees into two or more trees. 相似文献
11.
经营措施对杨树木材性质的影响 总被引:1,自引:0,他引:1
实施工业用材林定向培育,不仅单位面积上的产量高,而且要求生产出的木材质量要满足木材工业对各类木材原料的要求。简要阐述了造林密度、灌溉、施肥、立地条件和间伐等经营措施对杨树人工林木材性质的影响,旨在为杨树人工林定向培育组装优化栽培模式提供依据。 相似文献
12.
In a 4‐year‐old collection of native Italian Populus alba, growing in the eastern Po valley, many trunks showed severe symptoms characterized by brown spots, similar to trunk scab and/or by cankers. Canker‐like growths, often with gall‐like‐formations in the earlier developmental phases were also found on some clones of P. trichocarpa and their hybrids, as well as on P. deltoides growing in several Northern Italian nurseries. Bacteria and fungi present in the affected tissues and potentially involved in the disease were examined. No fungi were detected, however, several species of bacteria were isolated and identified: Pseudomonas mendocina and Erwinia herbicola group, from the brown spots; Erwinia carotovora sub sp. carotovora and, occasionally, E. herbicola group, from cankers. Only E. carotovora sub sp. carotovora produced clear symptoms of canker when artificially inoculated on young plants of different poplar species. This is the first time this symptomology on poplar species has been clearly related to E. carotovora sub sp. carotovora. 相似文献
13.
The carbon (C) stocks of forests are usually calculated from inventory-based estimates of the stem volume, tree-species-specific wood densities, biomass expansion factors (BEF) and functions for the mass of branches and needles/leaves, and the C concentration. However, reported BEFs in the literature are inconsistent, and especially the reliability of the C stock estimates for young stands is unknown. We describe an efficient method for deriving locally valid functions in order to estimate the aboveground biomass of young Norway spruce (Picea abies Karst.) stands. Data were collected from two adjacent stands, representing the treatment Control and Fertilized of an amelioration experiment. The stem volume was derived from Mass Tables as a function of diameter and height and was converted to stem mass with a species-specific conversion factor. Subsamples of branches from different positions within the canopy were selected by probability proportional to size (PPS) sampling. Needles and branches were weighed separately. The obtained expansion functions for branch and needle biomass have dbh as the only input variable and are accurate (0.88<R2<0.96). Earlier published allometric functions carried a considerable bias, especially when applied for young stands. We found that differences in soil fertility do not alter the ratio between the masses of stems, branches, and needles. Regionally derived biomass expansion functions can be used for sites with different soil fertility, can greatly improve the estimate of the aboveground biomass, and can be generated with a modest effort of field and laboratory work. 相似文献
14.
In this paper, the seasonal rhythms of the above grassland biomass of the two main types of theCalamagrostis angustifolia grasslands, theCalamagrostis angustifolia meadow and theCalamagrostis angustifolia +Carex schmiditii swamp meadow, were reported. The simulation technique was employed to described the dynamic process. In the end, the absolute
growth rate and the relative growth rate of aboveground biomass of the two communities were approached in the light of the
growth analysis method. 相似文献
15.
Ludovic Bonhomme Cécile Barbaroux Romain Monclus Domenico Morabito Alain Berthelot Marc Villar Erwin Dreyer Franck Brignolas 《Annals of Forest Science》2008,65(5):503-503
16.
Vegetation control (VC) in forest plantations often increases growth of crop trees but can also affect biomass and nutrient
partitioning to tree components. We examined above-ground biomass and macronutrients, leaf area and crown structure in 5-year
old Douglas-fir (Pseudotsuga menziessi (Mirb.) Franco) growing with VC and with no vegetation control (NVC) in coastal Washington, United States of America. Trees
in VC had larger stem, branch, foliage and total biomass than trees of equal stem diameter at 1.3 m above ground in NVC. The
difference in component biomass between treatments was in the order: branch > foliage > stem. Trees in the VC regime did not
differ in macronutrient concentration in stem, branch and foliage except for branch N which was greater in NVC than in VC.
Differences in tree macronutrient stores between VC and NVC ranged from 2.2 times for Mg to 2.6 times for N and K. The relationship
between stem diameter and leaf area was linear in both VC treatments. The relationship between stem diameter and foliage biomass
was curvilinear for both VC treatments. Results of this study support the need for separated allometric equations to estimate
biomass for young Douglas-fir growing in areas with and without VC. 相似文献
17.
Allometric models for estimating aboveground biomass
of shade trees and coffee bushes grown together
Allometric models for dominant shade tree species and coffee plants (Coffea arabica) were developed for coffee agroforestry systems in Matagalpa, Nicaragua. The studied shade tree species were Cordia alliodora, Juglans olanchana, Inga tonduzzi and I. punctata. The models predict aboveground biomass based on diameter at breast height (for trees), and the stem diameter at a height of 15 cm and plant height (for coffee plants). In addition, the specific gravity of the studied species was determined.The total aboveground biomass of the shade trees varied between 3.5 and 386 kg per tree, and between 0.005 and 2.8 kg per plant for coffee. The aboveground biomass components (foliage, branch, and stem) are closely related with diameter at breast height (r > 0.75). The best-fit models for aboveground biomass of the shade trees were logarithmic, with adjusted R
2 between 0.71 and 0.97. In coffee plants, a high correlation was found (r = 0.84) with the stem diameter at 15 cm height, and the best-fit model was logarithmic, as well. The mean specific gravity was 0.52 (± 0.11) for trees and 0.82 (± 0.06) for coffee plants. 相似文献
18.
Delphine Gourcilleau Marie-Béatrice Bogeat-Triboulot Didier Le Thiec Clément Lafon-Placette Alain Delaunay Walid Abu El-Soud Franck Brignolas Stéphane Maury 《Annals of Forest Science》2010,67(2):208-208
19.
Sergio de-Miguel Timo Pukkala Nabil Assaf Zuheir Shater 《Annals of Forest Science》2014,71(1):101-112
? Context
Biomass prediction is important when dealing for instance with carbon sequestration, wildfire modeling, or bioenergy supply. Although allometric models based on destructive sampling provide accurate estimates, alternative species-specific equations often yield considerably different biomass predictions. An important source of intra-specific variability remains unexplained.? Aims
The aims of the study were to inspect and assess intra-specific differences in aboveground biomass of Pinus brutia Ten. and to fill the gap in knowledge on biomass prediction for this species.? Methods
Two hundred one trees between 2.3 and 55.8 cm in diameter at breast height were sampled throughout the eastern- and southernmost natural distribution area of P. brutia, in Middle East, where it forms different stand structures. Allometric equations were fitted separately for two countries. The differences in biomass prediction at tree, stand, and forest level were analyzed. The effect of stand structure and past forest management was discussed.? Results
Between-country differences in total aboveground biomass were not large. However, differences in biomass stock were large when tree components were analyzed separately. Trees had higher stem biomass and lower crown biomass in dense even-aged stands than in more uneven-aged and sparse stands.? Conclusion
Biomass and carbon predictions could be improved by taking into account stand structure in biomass models. 相似文献20.
Amsalu Abich Tadesse Mucheye Mequanent Tebikew Yohanns Gebremariam Asmamaw Alemu 《林业研究》2019,(5):1619-1632
Allometric equations are important for quantifying biomass and carbon storage in terrestrial forest ecosystems.However,equations for dry deciduous woodland ecosystems,an important carbon sink in the lowland areas of Ethiopia have not as yet been developed.This study attempts to develop and evaluate species-specific allometric equations for predicting aboveground biomass(AGB)of dominant woody species based on data from destructive sampling for Combretum collinum,Combretum molle,Combretum harotomannianum,Terminalia laxiflora and mixed-species.Diameter at breast height ranged from 5 to 30 cm.Two empirical equations were developed using DBH(Eq.1)and height(Eq.2).Equation 2 gave better AGB estimations than Eq.1.The inclusion of both DBH and H were the best estimate biometric variables for AGB.Further,the equations were evaluated and compared with common generic allometric equations.The result showed that our allometric equations are appropriate for estimating AGB.The development and application of empirical species-specific allometric equations is crucial to improve biomass and carbon stock estimation for dry woodland ecosystems. 相似文献