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1.
Semi-arid adapted nitrogen fixing trees of the genus Prosopis have been extensively used in Argentina for soil improvement, luxury quality lumber production and sweet (35% sucrose) pods for humans and livestock. Due to the great demand of Prosopis alba for lumber, erect, tall, high pod producing trees of this species have been greatly overharvested, leading to erosion of the gene pool. A previous progeny trial with 57 half sib families identified 12 trees with promise for rapid growth, high production of pods and sweet pods. This trial, on a site with a salinity of 8.6 dS m−1 EC and a pH of 7.7, examined clones of these 12 trees in a randomized complete block trial with 8 single tree replications for height, basal diameter, canopy height and diameter, production of pods, sensory characteristics of the pods, disease resistance and insect resistance. In the 5th year of production and 7th year from planting, three clones produced more than 50 kg pods per tree versus 32 kg for check. At this 10 m × 10 m spacing, this yield of 5000 kg/ha compares favorably to many other semi-arid crops, especially given the unfavorable salinity and pH. In contrast to genetic improvement in pod production, the clones had lower diameter, height and canopy growth than the check. The lower biomass production may be due to fibrous root system produced from cuttings, since some of the clones blew over in high winds but none of the checks produced from seed blew over. Companion seed orchards of salt tolerant clones may provide rootstock for these high pod production clones. Significant differences in insect and disease resistance of the clones were observed and full sib crosses were made to study the genetics of the resistance. All clones had good sensory properties for use in human food. This is the first replicated trial with multipurpose clones useful for lumber and human food. The annual diameter growth rates ranged from 2.8 to 4.1 cm year−1 which was estimated to produce an internal return of approximately 20% from lumber alone. 相似文献
2.
The nitrogen fixing trees of the Prosopis juliflora/P. pallida complex are among the most adaptable and fastest growing trees in the truly tropical arid regions and have become naturalized
in semi-arid tropics in Latin America, the Caribbean, Hawaii, Sahelian Africa, the Indian subcontinent and northern Australia.
The trees have been regarded both as a serious weed and as a valuable resource for firewood and dune stabilization. Unfortunately
the introductions into Sahelian Africa and the Indian subcontinent were from trees that had non-palatable pods. Despite their
widespread occurrence, seed from a genetic improvement program is not available. Peruvian Prosopis has rapid growth, erect form and high survival of in Haiti, Cape Verde and India. An evaluation of form, diameter at breast
height, pod production and pod palatability was conducted in a 10 year old plantation of 1,800 trees in Piura, Peru and seven
were selected that had: more than 20 cm DBH; an erect form; 100% of branches with pods; and pods with a very sweet flavor.
Scions and budwood were taken from these trees and successively grafted onto greenhouse grown stock plants to be used for
clonal multiplication. For the first time we report successful chip budding grafting of Prosopis. This is the first report of Peruvian clones that have been selected for high production of highly palatable sweet pods.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
3.
Trunk circumferences and canopy diameters of Prosopis glandulosa, P. chilensis and P. alba, and soil nitrogen under and between the trees were measured in a seven-year-old plantation at the University of California,
Riverside. P. glandulosa had the smallest biomass of the three species. However, the nitrogen concentration of the soil under P. glandulosa was higher than under the other two species. Presumably more nitrogen is cycled through the leaves of this species rather
than invested in wood production, where it would be sequestered. The soil nitrogen accumulation under P. glandulosa was significantly higher (total and subsurface) than that measured in soil taken between trees. The soil nitrogen content
under P. chilensis and P. alba was not significantly different than that between the trees. These results indicate that the choice of woody legume in an
agroforestry system will depend on its intended use. The most efficient nutrient cycling is not necessarily associated with
the best biomass production. 相似文献
4.
Chemulanga Josiah Chiveu Otto George Dangasuk Michael Eliazar Omunyin Francis Nyamu Wachira 《New Forests》2009,38(1):1-14
Acacia senegal (L.) Willd. is an African leguminous multipurpose tree species belonging to subfamily Mimosoideae and subgenus Aculeiferum, highly valued for gum arabic production. This study estimated the genetic diversity within and among Kenyan populations
of the species in the Bulla Sambul, Kutulo, Wamba and Meisori populations based on 12 quantitative traits, which included;
tree height, diameter at breast height (DBH), number of branches, bark thickness, gum weight and various pod and seed traits
on 20 randomly selected trees in every population. Duncan’s multiple range test (DMRT) and the dendrogram distinctively divided
the populations into two groups; Wamba and Meisori in one group while Bulla Sambul and Kutulo in the other, indicating geographical
structuring of the genetic variability. The trees were larger, taller with greater pod and seed traits in the Wamba and Meisori
than the Bulla Sambul and Kutulo populations. Contrarily, trees had lighter seeds, more branches with higher gum weight in
the Kutulo and Bulla Sambul than the Wamba and Meisori populations. The Shannon–Weaver diversity index (H), depicted 1,000-seed weight as the most varied trait across the populations. These findings provide essential information
on the genetic diversity of the species, necessary for delineation of particular zones for seed sources for germplasm conservation,
selection for domestication and improved gum arabic production. 相似文献
5.
Timothy wojtusik Peter Felker Edward J. Russell Michael D. Benge 《Agroforestry Systems》1993,21(3):293-300
A progeny trial in Haiti compared 70 open-pollinated families ofProsopis representing seed sources from Haiti, Peru, Chile, Argentina and southwestern US. At the end of 4 years growth, the tallest 6 families were of Peruvian origin. Some of these Peruvian trees (probablyP. juliflora) were thornless, had erect habit and were non-browsed by goats, unlike other thornlessProsopis alba families from South America. Scions from the 5 tallest spineless and most erect trees were transported from Haiti to Texas A&I University where they were successfully grafted ontoP. alba rootstock. These scions should have great potential for grafting onto existing weedyProsopis and for grafting onto rootstock previously shown to tolerate salinities of seawater and pH values of 10.3. 相似文献
6.
We developed site-specific allometric models for Leucaena leucocephala × pallida var. KX2 trees in a shaded coffee agroecosystem in Hawaii to predict above- and belowground biomass and the regrowth potential
of pollarded trees. Models were used to compare tree growth rates in an experimental agroforestry system with different pollarding
frequencies and additions of tree pruning residues as mulch. For all allometric equations, a simple power model (Y = aXb) provided the optimal prediction of biomass or regrowth after pollarding. For aboveground biomass components (stem, branches,
leaves, and seed and pods), stem diameter alone was the best predictor variable. Stump diameter provided the best prediction
of coarse root biomass and aboveground regrowth after pollarding. Predictions of biomass from generalized allometric models
often fell outside the 95% confidence intervals of our site-specific models, especially as biomass increased. The combination
of pollarding trees once per year plus the addition of tree mulch resulted in the greatest aboveground regrowth rates as well
as accumulation of biomass and C in the stump plus coarse roots. Although optimal prediction required the development of site-specific
allometric relationships, a simple power model using stem or stump diameter alone can provide an accurate assessment of above-
and belowground tree biomass, as well as regrowth potential under specific management scenarios. 相似文献
7.
Timber production and cocoa yields were studied (initial 10?C11?years) in two experimental plantations: a Cocoa-Legume system (CL, Erythrina poeppigiana, Gliricidia sepium or Inga edulis), and a Cocoa-Timber system (CT, Cordia alliodora, Tabebuia rosea or Terminalia ivorensis, plus I. edulis for inter-site comparisons). These trials had two major goals: (1) to evaluate the use of mono-specific timber shade canopies as an alternative to traditional, mono-specific, legume service shade tree canopies; and (2) to determine the production potential of ten cocoa clonal bi-crosses under these shade tree species. Within each site, shade tree species did not influence dry cocoa bean yield nor pod counts (total number of pods produced, number of healthy pods harvested, pod losses due to monilia [Moniliophthora roreri], black pod [Phytophthora palmivora] or other causes??birds and squirrels in this study-, and total pod losses). Significant differences were found between cocoa bi-crosses for both cocoa bean yield and pod counts. Sites differed only in terms of total pod losses (43% in CL; 54% in CT) and their causal factors (mainly monilia in CL; both monilia, squirrels and birds in CT). At CT, all timber tree species grew rapidly, reaching 30?C34?cm?dbh, 17?C25?m total tree height and 97?C172?m3?ha?1 total stem volume (age 10?years). Timber species should be promoted for the shade component of cacao plantations given their potential production and the fact that their presence did not negatively affect cocoa yields. 相似文献
8.
Microclimate and nutrient dynamics in a silvopastoral system of semiarid northeastern Brazil 总被引:2,自引:0,他引:2
There is little available information on nutrient cycling and the controls of ecosystem processes in land use systems of dry neotropical regions. In this study, we conducted field and glasshouse experiments to investigate the influence of Ziziphus joazeiro and Prosopis juliflora trees on microclimate and nutrient dynamics in pastures ofCenchrus ciliaris in semiarid northeastern Brazil. We found that soil moisture was lower under the crowns of P. juliflora trees during early season in comparison to patches ofC. ciliaris (grass patches), but the presence of Z. joazeiro had no effect on soil moisture. Soil and air temperatures were lower under Z. joazeiro in comparison to grass patches but P. juliflora had little effect on temperature. Losses of P from all litter types were lower under the crowns of Z. joazeiro trees, but losses of biomass and N from litter were not consistently affected by the presence of trees. Soil net N mineralized was greater under both tree species, in comparison to grass patches. However, net soil N mineralized per gram of total soil N was greater under the crowns of the potentially N2 fixing P. juliflora, in comparison to grass patches, while there were no significant differences betweenZ. joazeiro crowns and grass patches. In the glasshouse study, plant biomass and nutrient uptake was greater in soil collected under the crowns of both tree species, in comparison to soil from grass patches. Our results indicate that the preservation of native trees or introduction of exotic tree species in C. ciliaris pastures in semiarid northeastern Brazil significantly affects microclimate and the dynamics of litter and soil nutrients, and may contribute to increases in the cycling rate of nutrients in these systems. Index terms: buffel grass, caatinga, nitrogen mineralization, Prosopis juliflora, Ziziphus joazeiro.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
9.
Tsutomu Enoki Takafumi Inoue Naoaki Tashiro Hiroaki Ishii 《Journal of Forest Research》2011,16(4):268-274
We measured the aboveground biomass, biomass increment and litterfall production of a 140-year-old, abandoned Cryptomeria japonica plantation in order to infer the effects of topography on biomass production. The plantation was unsuccessful and the naturally
regenerated broad-leaved trees contributed 93.4% (374.2 Mg ha−1) of the total aboveground biomass (400.2 Mg ha−1). Comparing between different slope positions, aboveground biomass decreased downslope corresponding to the decrease in broad-leaved
tree biomass. The biomass of C. japonica did not vary with slope position. Biomass increment and litterfall production of the broad-leaved trees also decreased downslope.
However, litterfall production per unit biomass and aboveground net primary production per unit biomass increased downslope.
Results of a path analysis showed that biomass increment of C. japonica decreased with increasing topographical convexity, whereas biomass and litterfall production of broad-leaved tree increased.
Litterfall production of broad-leaved tree decreased with increasing biomass of C. japonica, suggesting that, despite their small biomass, the presence of residual C. japonica may have negative effects on the distribution and productivity of the broad-leaved trees. Our results indicated that total
aboveground biomass of the study site was comparable to that of old-growth C. japonica plantations. We inferred that the variation in aboveground biomass of the broad-leaved trees was largely determined by the
topography, while their productivity was affected by interactions with planted C. japonica. 相似文献
10.
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
11.
Katja Albert Peter Annighöfer Jens Schumacher Christian Ammer 《Scandinavian Journal of Forest Research》2014,29(3):210-221
With an increasing demand of sustainable raw materials for bioenergy use, coppicing as management approach to increase the biomass production of forests is becoming of greater importance. This study describes the parameterization of biomass equations for six tree species traditionally used in coppices forests, namely sycamore maple (Acer pseudoplatanus L.), field maple (Acer campestre L.), European ash (Fraxinus excelsior L.), European hornbeam (Carpinus betulus L.), downy birch (Betula pubescens Ehrh.), and common hazel (Corylus avellana L.) growing in coppice-with-standard systems in Lower Saxony, Germany. The parameterization was based on measurements of over 950 trees sampled from two forest sites. The sampled trees were felled and separated into three biomass compartments (stem, coarse branches, and fine brushwood) and weighed on site. The dry weight of sub samples from each compartment was measured. Equations were derived for total aboveground biomass, stem biomass, and crown biomass using regression analyses. We either used diameter at breast height as single independent explanatory variable or in combination with tree height. Biomass production of stump sprouts and generatively grown stems was compared for ash and sycamore maple. In the same age classes, it was found that ash stump sprouts had a slightly higher production than seed-grown stems. For sycamore maple, no difference was detected. 相似文献
12.
山地木麻黄(CasuarinajunghuhnianaMiq.)原产于印度尼西亚,属木麻黄科(Casuarinaceae),树干通直,生长快,抗干旱,耐水湿,可生长于多种类型土壤,成熟林木高可达35m,胸径可达65~100cm。其天然分布为7°~10°S,110°~127°E,海拔1000~3100m的山地,但海平面附近地区也有出现,降水为夏雨型,年降水量为700~1500mm,有的高达2000mm,年平均气温13~28℃。山地木麻黄木材热值高,适于作薪材、木炭产品、建筑用材、矿柱和电杆等。国内外对山地木麻黄的研究主要涉及分类、分布、引种和生长表现[1~11]。1985年,中澳合作项目ACIAR8457我国首次引进… 相似文献
13.
M. J. Rozados-Lorenzo M. P. González-Hernández F. J. Silva-Pando 《Agroforestry Systems》2007,70(1):53-62
We studied the effect of six tree species planted at six different densities on pasture production seven years after establishment.
Annual and seasonal pasture production was studied every six months, over three years. Pasture production was lower under
conifer trees (Pseudotsuga menziesii (Mirb.) Franco, Pinus pinaster Aiton, Pinus radiata D. Don) than under broadleaved trees (Betula alba L., Quercus rubra L. and Castanea sativa Mill.). Annual pasture production under Pseudotsuga menziesii and Pinus pinaster decreased progressively starting from 952 trees ha−1, while decline in herbage production under Pinus radiata began to occur at 427 trees ha−1. Tree density effect on pasture production was detected at 2,000 trees ha−1 for all of the deciduous species studied. This effect on pasture production was more important in the first six months of
the year (June sampling), while from June to December herbage production was less affected by tree density. The tree effect
became more noticeable over time, with the last sampling showing the inverse relationship between tree density and herbage
production most clearly. Seven years after tree establishment, pasture production was quite consistent under tree densities
between 190 trees ha−1 and 556 trees ha−1 and declined remarkably from 556 trees ha−1 to 2,500 trees ha−1. The study also indicated that by the sixth growing season, annual pasture production under different tree species is inversely
correlated with tree leaf area index. 相似文献
14.
Demand for goat (Capra hircus) meat in the southeastern USA is steadily increasing as a result of preferences exhibited by ethnic communities. Feeding
systems that include fodder trees can be developed to take advantage of the natural preference of goats for browse. Data were
collected for 2 years on a 5-year old stand of Robinia pseudoacacia L. to evaluate growth characteristics for goat browse and to develop allometric relationships in a randomized complete block
design (intra-row spacing 0.5 or 1 m and coppice height 0.25 or 0.50 m) replicated six times. Allometric equations were derived
from destructive harvests of 68 trees. Main branch size was not affected by intra-row spacing when trees were coppiced at
0.25 m; however, when coppiced at 0.5 m, trees spaced at 1 m had more and larger branches (P < 0.05) than trees spaced at 0.5 m. Intra-row spacing did not influence tree herbage biomass when trees were spaced at 0.5 m
whereas trees coppiced at 0.25 m and spaced at 1 m produced less woody and herbaceous biomass than trees spaced at 0.5 m (P < 0.05). A strong relationship (P < 0.0001) was found between tree herbage biomass and the number of main branches greater than 0.01 m (r
2 = 0.80). The results, based on growth characteristics and tree herbage biomass production, suggest that Robinia pseudoacacia L. would be an excellent candidate as a silvopastoral component in the southeastern USA. 相似文献
15.
The first generation genetic gains in four second-generation seedling seed orchards of Eucalyptus pellita established at two locations in Indonesia (Kalimantan and Sumatra) were examined by analyzing data on the height, diameter
and stem form of the trees during years 1 to 3. The seed orchards each consisted of 60 open-pollinated families: 48–49 families
from first-generation plus trees (improved population) and 11–12 families from natural forest (unimproved population). The
realized gains for height and diameter were ca. 16 and 19%, respectively. These gains were highly significant and consistent,
irrespective of age and location. However, the gains in stem form were much lower (4%) in Kalimantan than in Sumatra (21%)
and only significant in the latter, possibly because of the more intensive silvicultural management regimes at the Sumatran
sites. The results confirmed that the first-generation tree improvement program for E. pellita has been effective in Indonesia, and that it should provide improved seeds for operational plantation, thus raising their
productivity. 相似文献
16.
西非Sudanian热带林地11个树种地上生物量异速生长预测 总被引:1,自引:0,他引:1
Louis Sawadogo Patrice Savadogo Daniel Tiveau Sidzabda Djibril Dayamba Didier Zida Yves Nouvellet Per Christer Oden Sita Guinko 《林业研究》2010,21(4):475-481
Allometric models are necessary for estimating biomass in terrestrial ecosystems. Generalized allometric relationship exists
for many tropical trees, but species- and region-specific models are often lacking. We developed species-specific allometric
models to predict aboveground biomass for 11 native tree species of the Sudanian savanna-woodlands. Diameters at the base
and at breast height, with species means ranging respectively from 11 to 28 cm and 9 to 19 cm, and the height of the trees
were used as predictor variables. Sampled trees spanned a wide range of sizes including the largest sizes these species can
reach. As a response variable, the biomass of the trees was obtained through destructive sampling of 4 754 trees during wood
harvesting. We used a stepwise multiple regression analysis with backward elimination procedure to develop models separately
predicting, total biomass of the trees, stem biomass, and biomass of branches and twigs. All species-specific regression models
relating biomass with measured tree dimensions were highly significant (p < 0.001). The biomass of branches and twigs was less predictable compared to stem biomass and total biomass, although their
models required fewer predictors and predictor interactions. The best-fit equations for total above-ground biomass and stem
biomass had R
2 > 0.70, except for the Acacia species; for branches including twig biomass, R2-values varied from 0.749 for Anogeissus leiocarpa to 0.183 for Acacia macrostachya. The use of these equations in estimating available biomass will avoid destructive sampling, and aid in planning for sustainable
use of these species. 相似文献
17.
Early-growth differentiation among seven provenances of Prosopis flexuosa (algarrobo dulce) from the Monte phytogeographic province, Argentina, was studied by comparing their height growth; whole-seedling dry mass gain; allocation to root, stem and leaves; leaf number and leaf area in a common garden. Differentiation among provenances was detected for all the seedling characters examined except leaf number. Family variation within provenances was significant for height growth and leaf number. Variation on the provenance level was related to the elevation, geographic location, and some abiotic conditions of the seed source such as mean annual temperature and frost free period. Latitudinal clines were evident for almost all the growth traits. They were more pronounced for height and aboveground mass, and moderate for total plant mass and leaf area per plant. In addition, a good correspondence in growth traits between young seedlings and older trees of this species (studied by others authors) was also assessed. This fact would permit an early selection and genetic advances in the short term in breeding programs. 相似文献
18.
R. S. Yadav B. L. Yadav B. R. Chhipa S. K. Dhyani Munna Ram 《Agroforestry Systems》2011,81(3):195-202
An investigation was carried out in an Entisol at farmers’ field in Jaipur district, Rajasthan, India during 2002–2004 to evaluate the effect of traditionally grown trees
on soil biological characteristics. Traditionally grown trees in farm lands for study consisted of Prosopis cineraria (L.), Dalbergia sissoo (Roxb.) ex DC, Acacia leucophloea (Roxb.) and Acacia nilotica (L.) Del. having a canopy diameter of 8 m. Results revealed significant and substantial improvement in soil biological activity
in terms of microbial biomass C, N and P, dehydrogenase and alkaline phosphatase activity under different tree based agroforestry
systems as compared to a no tree control (cropping alone). Soil microbial biomass C, N and P under agroforestry varied between
262–320, 32.1–42.4 and 11.6–15.6 μg g−1 soil, respectively, with corresponding microbial biomass C, N and P of 186, 23.2 and 8.4 μg g−1 soil under a no tree control. Fluxes of C, N and P through microbial biomass were also significantly higher in P. cineraria based land use system followed by D. sissoo, A. leucophloea and Acacia nilotica in comparison to a no tree control. Thus, it is concluded that agroforestry system at farmers’ field enhance soil biological
activity and amongst trees, P. cineraria based system brought maximum and significant improvement in soil biological activity. 相似文献
19.
《Southern Forests》2013,75(2):77-88
Estimating tree volume and biomass constitutes an essential part of the forest resources assessment and the evaluation of the climate change mitigation potential of forests through biomass accumulation and carbon sequestration. This research article provides stem volume and biomass equations applicable to five tree species, namely Afzelia africana Sm. (Caesalpiniaceae), Anogeissus leiocarpa (DC.) Guill. and Perr. (Combretaceae), Ceiba pentandra (L.) Gaertn. (Bombacaceae), Dialium guineense Willd. (Caesalpiniaceae), Diospyros mespiliformis Hochst. ex A.DC. (Ebenaceae) in natural protected tropical forests and, in addition, Tectona grandis L.f. (Verbenaceae) in plantations. In addition to the tree species specific equations, basic wood density, as well as carbon, nitrogen, organic matter and ash content were determined for these tree species in tropical conditions in West Africa. One hundred and sixty-two sample trees were measured through non-destructive sampling and analysed for volume and biomass. Stem biomass and stem volume were modelled as a function of diameter (at breast height; Dbh) and stem height (height to the crown base). Logarithmic models are presented that utilise Dbh and height data to predict tree component biomass and stem volumes. Alternative models are given that afford prediction based on Dbh data alone, assuming height data to be unavailable. Models that include height are preferred, having better predictive capabilities. Ranges in carbon, nitrogen and ash contents are given as well. The successful development of predictive models through the use of non-destructive methods in this study provide valuable data and tools for use in determining the contribution of these major African rainforest tree species to global carbon stocks, while ensuring the preservation of this valued African resource. This study needs to be expanded to further regions and tree species to complete a full inventory of all tree species, emphasising the relevance of African trees to carbon stocks at a global scale. 相似文献
20.
Sorghum (Sorghum bicolor L. Moench) production in 15 transect blocks, each with a karité (Vitellaria paradoxa C. F. Gaertn.) tree at each end, was evaluated on-farm in a village of southern Burkina Faso in a season of below-average rainfall. Under tree crowns, plant height and grain yield were significantly lower, by a factor of 16% for grain yield, than elsewhere in transects. In addition, mean plant height, and mean biomass and grain production per area as well as per plant were higher at the outside edge of tree crowns than in the middle of the field. Soil moisture content decreased significantly with increasing distance from the tree in the 0–20 cm soil layer. Top soils were also richer in organic carbon and potassium around tree crowns than in the middle of blocks. Sorghum performance in the zone under and around canopies was projected at field scale and compared to central transect controls. Grain production in karité parklands was higher with trees of mean crown radii of 225 to 275 cm, average densities of 12 and 31 trees/ha than in areas without trees. Therefore, farmers do not improve cereal production by reducing parkland tree densities below these levels. When nut production is included in the analysis, maintaining trees in fields can be economically advantageous at all densities.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献