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1.
Pasture production in a silvopastoral system in relation with microclimate variables in the atlantic coast of Spain 总被引：1，自引：0，他引：1
F.J. Silva-Pando M.P. González-Hernández M.J. Rozados-Lorenzo 《Agroforestry Systems》2002,56(3):203-211
Grasses and legumes of high productivity and nutritional quality are a good alternative as pasture supplements in rangelands of low quality forage. Orchardgrass (Dactylis glomerata L. cv. `Artabro') and white clover (Trifolium repens L. cv. `Huia') are known as shade tolerant and low flammability species that have been successfully used in agroforestry systems in Galicia, both diminishing fire hazard compared with natural shrublands. In this study, annual and seasonal production of a grass mixture of both species was quantified during 3 years in a pinewood under different tree canopy covers. Regardless of cover, pasture production increased in summer, and decreased from fall to spring. We obtained a significant correlation between annual pasture production and light transmission through the tree canopy (R2 = 0.96, P<0.05). Light transmittance through a maritime pine canopy (Pinus pinaster Ait.) was higher than through a Scots pine canopy (P. sylvestris L.), corresponding to 36–57% and 16–21% of full sunlight respectively. The highest herbage production was obtained in no tree stands and the lowest under a P. sylvestris canopy. Fluctuations inlight transmission, temperature and PAR (Photosynthetically Active Radiation) under tree canopy were less apparent compared with no tree stands. Variation in seasonal production was more pronounced in stands without trees, and appeared more uniform when percentage of light intercepted by tree canopy increased.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
2.
Giovanna Seddaiu Simonetta Bagella Antonio Pulina Chiara Cappai Lorenzo Salis Ivo Rossetti Roberto Lai Pier Paolo Roggero 《Agroforestry Systems》2018,92(4):893-908
Mediterranean wooded grasslands that emerge from silvopastoral activities are multifunctional systems that result in high biodiversity and offer ecosystem services such as forage production and soil carbon sequestration. During 3 years, ten grazed wooded grassland fields were studied in the Berchidda–Monti long-term observatory, located in NE Sardinia, Italy, with the aim of exploring the synergies and trade-offs between biodiversity and selected ecosystem services. Positions below and outside the canopy of three cork oak trees in each field were randomly selected to compare seasonal pasture production, pasture utilization rate by animals, botanical composition, biodiversity indicators (Shannon index and plant species richness) and soil organic carbon. In autumn, dry matter production of pasture was similar in the two positions; in two winters out of three it was greater below the trees than outside, and in spring it was greater outside than below the trees. While plant species richness and Shannon index were not significantly influenced by the position, the overall wooded grassland plant species richness was 31% higher than that outside of the tree crown. The soil organic carbon content in the 0–40-cm soil layer was also higher below the trees. Our findings highlight that if the main purpose of the wooded grasslands is to provide forage for grazing animals rather than conserving and/or enhancing plant diversity and soil fertility, the presence of trees constrains the overall forage productivity, although the greater forage availability in winter under the trees can contribute to improve the seasonal distribution of forage production. 相似文献
3.
Resource sharing between tree and forage plant components in silvopastoral systems includes a complex set of facilitative and competitive interactions. To the extent that facilitation exceeds competition, agroforests are expected to outyield monocultures of their components. Pasture and Douglas fir (Pseudotsuga menziesii) tree production of young agroforests was compared to pasture and forest monocultures under both grid and cluster patterns of tree planting near Corvallis, Oregon, USA, during 1983–1987. The height and diameter growth of forest and agroforest trees was similar, regardless of tree planting pattern. Five-year average annual forage production was 6500, 5800, and 2800 kg ha–1 on pasture, agroforest, and forest plots, respectively. The total cumulative 1982–1987 above-ground phytomass yield of forage plus trees was similar for pasture and conventional grid forest monocultures. The total productivity of agroforests, however, was over 30% greater than either pasture or forest components grown in monoculture. Approximately 1.6 ha (0.96 ha forest + 0.64 ha pasture) of monocultures would be needed to equal the productivity of 1 ha of agroforest.Oregon Agricultural Experiment Station Technical Paper No. 10, 825. 相似文献
4.
5.
J-M. Luginbuhl T. E. Harvey J. T. Green Jr M. H. Poore J. P. Mueller 《Agroforestry Systems》1998,44(2-3):241-252
Much of hill-land pasture in the Appalachian region of the United States is dominated by herbaceous weeds and brush. Low cost,
low input and environmentally acceptable reclamation procedures are needed to maintain the productivity of these pastures.
This experiment evaluated the effectiveness of using goats (Capra hircus hircus) alone (30 mature, brush does/ha) or cattle
(Bos taurus) with goats (17 mature, brush does/ha + two to three steers/ha -- 225 kg average live weight) to reclaim a pasture
from an abandoned, overgrown 5.9 ha orchard left untouched for 15 years. Over four grazing seasons, managed defoliation resulted
in a substantial increase in herbaceous vegetative cover in plots grazed by goats alone (65 to 86%) and by goats with cattle
(65 to 80%) while vegetative cover decreased from 70 to 22% in the control plot. Similarly, the cover by grass species increased
in the grazed plots (goats: 16 to 63%; goats + cattle: 13 to 54%) while averaging 10% in the control plot. Multiflora rose
(Rosa multiflora Thumb.) bushes were practically eliminated after four grazing seasons as quantified by an average reduction
in height from 2.1 m to 0.6 m, and by the number of dead canes (stems) in both the goat (100%) or goat + cattle (92%) treatments.
Results indicated that the foraging habits of goats resulted in the elimination of multiflora rose bushes and in a significant
increase in desirable forage species.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
6.
Silvopastures may have the potential to increase forage yields beneath trees compared to open pasture at some sites. This
has been attributed to a combination of factors including improved water use efficiency by shaded grass and increased water
availability through hydraulic lift by trees. The objectives of this research were to determine if silvopastures changed forage
mass production and available soil water, and to determine how these two factors were related. Forage mass and soil water
were sampled at 1.0, 2.0, and 3.6 m from the tree stem, or plot center under honey locust (Gleditsia triacanthos L.), black walnut (Juglans nigra L.) and shade cloth in 2006 and 2007. Soil water was measured in the top 10 cm of soil using a capacitance probe, and at
30-cm intervals, from 45 to 105 cm, using a neutron probe. Forage was collected to determine dry mass and annual yield. In
2006, forage mass was greater under black walnuts and honey locusts than under 70% shade cloth. In 2007, with a 50% shade
cloth, forage growth was similar in all treatments. In both 2006 and 2007, soil moisture in the top 10 cm was higher under
shade cloth compared to honey locust or black walnut trees. Similarities in forage mass between treatments in 2007 indicate
that the differences in soil water were not biologically significant for forage growth. Lower forage mass under the 70% shade
cloth in 2006 was due to suppressed growth from intense shading. The major implication for pasture managers is that trees
in these pastures had no negative effect on soil water availability and forage growth. 相似文献
7.
Dry deciduous forests of the eastern lateritic part of India are a typical case where forest valuation is yet to be integrated with the non-timber forest products like wild edible mushrooms (WEMs), which have a wide use in subsistence and cash income. A detailed accounting of the production and utilization of WEMs harvested from that region was made to highlight the economic worth of WEMs to the Santal community of this region. The WEMs production in the forest was in a polynomial pattern during the monsoon period. The net present value of revenues from WEMs was estimated to be contributing 9.83 and 10.29 % of total annual income of a Santal family of the Choupahari and Gonpur forests, respectively. The ecological footprint of the Santal communities on WEMs was higher in the forest area which was closer to the local markets than did the distant ones. Forest areas of the eastern lateritic part of India have a strong potentiality to produce WEMs that may be helpful for socio-economic upliftment of local tribal communities through the development of entrepreneurship and policy making. 相似文献
8.
Marisa Nordenstahl Pedro E. Gundel M. Pilar Clavijo Esteban G. Jobbágy 《Agroforestry Systems》2011,83(2):201-211
In managed rangelands periods of low primary productivity determine troughs of forage availability, constraining animal production
year-round. Although alternative tools to increase forage availability during critical seasons exists, most of them are unaffordable
and short-lived in marginal areas. We explore the potential benefits of deciduous tree plantations favoring winter forage
productivity by comparing aboveground net primary productivity (ANPP) patterns in herbaceous understory to tree plantations
and natural grasslands in the Pampas (Argentina). These temperate subhumid grasslands are characterized by the coexistence
of winter species, mainly C3 grasses of the native genera Stipa, Piptochaetium, and Bromus and the exotic genera Lolium and Festuca) and summer species (mainly C4 grasses of the native genera Paspalum, Bothriochloa, and Stenotaphrum) that replace each other throughout the seasons, with domination of the latter. We hypothesize that the natural decoupling
of growing seasons between winter deciduous trees and winter grasses could provide the basis for the sustainable promotion
of winter forage. We measured ANPP on two 23-year-old Populus deltoides plantations and their understory and compared them with adjacent open grasslands. Afforested stands had 55–75% higher annual
ANPP than their non-afforested neighbors, with trees contributing ~70% to total ANPP. Herbaceous canopies beneath plantations
achieved about half of the ANPP observed in non-afforested situations with a contrasting seasonal distribution associated
with shifts from C4 to C3 grass dominance. Winter ANPP, the most critical source of forage in these grazing systems, was similar
or higher in the herbaceous understory of tree plantations to that on their non-afforested counterparts, suggesting that mixed
systems involving deciduous trees and understory pastures are a valid and viable option in the region. 相似文献
9.
Satoru Okubo Parikesit Koji Harashina Dendi Muhamad Oekan S. Abdoellah Kazuhiko Takeuchi 《Agroforestry Systems》2010,80(1):17-31
Agroforestry systems have been re-evaluated with a renewed scientific interest as appropriate models for achieving sustainable
production while maintaining planned and associated biodiversity and agroecosystem functioning. Traditional bamboo-tree gardens
in West Java are known to play substantial ecological and socioeconomic roles. In this study, we attempted to elucidate the
relationship between income generation and biodiversity by studying 83 bamboo-tree gardens that varied in species composition
and degree of commercialization. We conducted a survey of the vegetation and interviewed the owners or managers of each plot.
We identified 42 planned and utilized species and 19 associated non-use species. Eight vegetation groups were identified by
two-way indicator species analysis (TWINSPAN), each of which varied in individual densities of different utilization species
types, Simpson’s diversity index, management intensities, and potential annual gross income. The group with the highest potential
income generation was dominated by clove trees (Syzygium aromaticum); however, this group also had a lower level of diversity and higher levels of management intensity than the other groups,
but all of the pairwise groups were not significantly different. About 60% of the villagers used at least some fuelwood as
a domestic energy source, and almost all of them collected fuelwood from bamboo-tree gardens regardless of ownership. There
were no significant differences in density of potential fuelwood species among the vegetation groups. There were significant
positive correlations between income and most management activities. The regression model between gross income and Simpson’s
diversity index with the best fit was a unimodal curve, which strongly suggests that maximum diversity can be conserved at
an intermediate level of income. Nevertheless, this intermediate level of gross income is probably not adequate as the primary
source of income for garden owners, although some gardens had the potential to achieve higher income levels with no decline
in diversity. We suggest that maximizing individual density and multistratifying canopy layers could improve profitability
within perennial crop-based agroforestry systems in West Java. 相似文献
10.
The study optimised the management of a Grevillea robusta (A. Cunn.) stand growing in the central highlands of Kenya. The optimisations were conducted separately for even-aged and uneven-aged management system of trees. The management was also optimised with the requirement that maize production under the tree cover must be profitable every year. Technically, the optimisation problems were solved by linking a simulation program with the non-linear optimisation algorithm of Hooke and Jeeves. The simulation program calculated the tree growth, volumes of harvested trees, and maize yields with a given set of management parameters (decision variables). The maize yield predictions and simulated timber yields were converted into gross incomes of which the production costs were subtracted. In even-aged management the objective variable was the soil expectation value with 5% discounting rate. In uneven-aged management the mean annual net income was maximised. The optimal solutions indicated that with both management systems it is optimal to concentrate on wood production. The optimal stand densities were so high that profitable maize production was not possible under the tree cover. The mean annual wood production of the optimal management schedule was more than 50m3 ha–1. Forcing profitable maize production in the solution decreased the wood production by 57% (even-aged forestry) or 27% (uneven-aged forestry) and net income by 45% (even-aged forestry) or 24% (uneven-aged forestry).This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
11.
A. Pantera P. J. Burgess R. Mosquera Losada G. Moreno M. L. López-Díaz N. Corroyer J. McAdam A. Rosati A. M. Papadopoulos A. Graves A. Rigueiro Rodríguez N. Ferreiro-Domínguez J. L. Fernández Lorenzo M. P. González-Hernández V. P. Papanastasis K. Mantzanas P. Van Lerberghe N. Malignier 《Agroforestry Systems》2018,92(4):945-959
Most farm-based agroforestry projects focus on the integration of trees on arable or livestock enterprises. This paper focuses on the integration of understorey crops and/or livestock within high value tree systems (e.g., apple orchards, olive groves, chestnut woodlands, and walnut plantations), and describes the components, structure, ecosystem services and economic value of ten case studies of this type of agroforestry across Europe. Although their ecological and socio-economic contexts vary, the systems share some common characteristics. The primary objective of the farmer is likely to remain the value of tree products like apples, olives, oranges, or nuts, or particularly high value timber. However there can still be production, environmental or economic benefits of integrating agricultural crops such as chickpeas and barley, or grazing an understorey grass crop with livestock. Three of the systems focused on the grazing of apple orchards with sheep in the UK and France. The introduction of sheep to apple orchards can minimise the need for mowing and provide an additional source of revenue. Throughout the Mediterranean, there is a need to improve the financial viability of olive groves. The case studies illustrate the possibility of intercropping traditional olive stands with chickpea in Greece, or the intercropping of wild asparagus in high density olive groves in Italy. Another system studied in Greece involves orange trees intercropped with chickpeas. Stands of chestnut trees in North-west Spain can provide feed for pigs when the fruit falls in November, and provide an excellent habitat for the commercial production of edible mushrooms. In Spain, in the production of high quality walnut trees using rotations of up to 50–60 years, there are options to establish a legume-based mixed pasture understorey and to introduce sheep to provide financial and environmental benefits. 相似文献
12.
Tomohiro Nishizono Kunihiro Tanaka Kazuo Hosoda Yoshio Awaya Yasuhiko Oishi 《Journal of Forest Research》2008,13(5):264-274
We analyzed data from 28 long-term experimental monitoring plots installed in Japanese cedar (Cryptomeria japonica D. Don) plantations in northeastern Japan to examine how site productivity and thinning practices relate to culmination in
stand growth. Site productivity and thinning practices in the plots were evaluated by site index (dominant tree height at
40-years old) and by cumulative thinning rate (cumulative thinning volume divided by cumulative gross production during the
entire period of measurement). Culmination of stand growth was evaluated by culmination age of the mean annual increment (MAI)
and its maximum value (Max MAI). Max MAI for the mean annual gross increment (MAIgross) and mean annual net increment (MAInet)
increased with increasing site index, but did not change with cumulative thinning rate. Culmination age for MAIgross decreased
with increasing site index, but did not change with cumulative thinning rate. Culmination age for MAInet decreased with increasing
site index. Additionally, culmination age for MAInet increased with increasing cumulative thinning rate in sites with a high
site index (>19.3 m) but not in those with a low site index (<19.3 m). These results indicate that thinning extends the culmination
age without changing Max MAInet under high site productivity. Therefore, thinning increases total net yield in sites with
high productivity based on a long-term perspective. 相似文献
13.
J. Cobbina 《Agroforestry Systems》1994,28(3):193-201
Interplanting Gliricidia (Gliricidia sepium [Jacq.] Walp.) into poor quality native grass can improve the quality of pasture. But information on methods to establish the tree legume into existing pasture is scarce. This study was designed to compare the effects of disc-ploughing, hoeing, or rotary tillage operations, and direct seeding or planting out potted seedlings on growth and dry matter yields of Gliricidia in grass pasture. The Guinea grass (Panicum maximum) pasture was first mowed to a height of 10 cm. Then the seedbed was prepared by either hoeing 0.5 m strip or rototilling 0.5 m strip with a 2-wheel tractor or disc-ploughing 1.0 m strip with a 4-wheel tractor. Eight weeks old potted seedlings were planted or seeds were sown direct. At 6 months after planting (MAP), trees in disc-ploughed strips averaged 81 cm in height, about 35% taller than trees in hoed- or rotary-tilled strips. Potted seedlings (average height 77 cm) grew 37% taller than direct-seeded trees. At 12 MAP trees in disc-ploughed strips yielded 95% more leaf DM (1170 vs. 600 kg/ha) than trees in hoed- or rotary-tilled strips. In order to intercrop Gliricidia into existing Guinea grass pasture, it is necessary to plant potted seedlings previously raised in nursery into 1.0 m wide strips disc-ploughed with 4-wheel tractor. Weed control is necessary. 相似文献
14.
The availability of public recreational facilities is being threatened by growing demands, limited supplies, and declining
government funding. In response to these pressures, the economic potential of agroforestry for supplementing operating budgets
of public recreational parks is examined in a case study park consisting of 324 hectares. Agroforestry enterprises native
to the area were selected for development on 70 hectares of the site. Linear programming was used to determine the optimum
combinations of 23 agroforestry regimes composed of the following activities: 1) conventional forestry planting, tree density
of 1682 trees/hectare, 2) the selected agroforestry planting with hay, tree density of 1495 trees/hectare, 3) the selected
agroforestry planting with grazing, 4) hay production, and 5) rental of pasture for grazing. The objective function of the
study was to maximize the net present value of the study site subject to land, labor, capital, and minimum annual income constraints.
The preferred optimal regime generated $1782 per hectare from an agroforestry planting configuration of 1495 trees/hectare
with 75 percent hay, 25 percent grazing, and no annual income requirements. Minimum annual income requirements of $2400 and
$4800 were feasible but suboptimal from a net present value criteria. The study found that agroforestry could be used to privatize
selective activities of public recreational parks and thus enable public agencies to provide these facilities more effectively. 相似文献
15.
Babassu palms (Orbignya spp.) cover nearly 200,000 km2 in Brazil, providing cash income, fuel, fibre, edible oil and food to a large number of tenant farm households. Babassu is closely integrated within pastoral and shifting cultivation systems of Mid-North Brazil. In pastures, babassu provides shade for cattle, aids soil moisture retention, produces organic matter, generates supplementary farm income at little cost, and offers year-round employment. On the other hand, the persistence of juvenile palms reduces pasture grass productivity due to plant competition, and therefore there is a trend to eradicate babassu through clearcutting and understorey suppression. At moderate densities of less than 100 individuals per ha, mature babassu palms in cropland do not appear to harm crop productivity. In such cases, palms are thinned and leaves of the remaining ones are cut back, supplying fuel for the burn and nutrients to the soil. However, reduced fallow cycles due to pasture conversion threaten babassu as well as crop productivity.
Resumo Palmeiras de babaçu (Orbignya spp.) occorrem em quase 200.000 km2 no Brazil, proporcionando renda em dinheiro, combustível, fibras, óleo e alimentos para cerca de quinhentas mil famílias de pequenos produtores rurais, a maioria arrendatários ou posseiros. O babaçu aparece integrado dentro de sistemas de produção pastorís e de agricultura migratória no Meio Norte do Brazil. Nas pastagens, o babaçu provê sombra para o gado, ajuda na retenção da umidade no solo, produz matéria orgânica, gera renda suplementar com investimento mínimo, e oferece condições para fixar a força de trabalho durante a entressafra dos produtos agrícolas. A presença de palmeiras juvenís, porém, reduz a produtividade dos pastos devido a competição, o que leva os criadores de gado a erradicar o babaçu, suprimindo tanto as palmeiras juvenís, como as palmeiras adultas.No que diz respeito à agricultura migratória, o babaçu adulto em densidades moderadas, ou seja, até 100 indivíduos por hectare, aparentemente não reduz a produtividade das culturas anuais. Nestes casos, parte das palmeiras são desbastadas e as folhas das restantes cortadas, proporcionando combustível para a queima e nutrientes para o solo. No entanto, a redução nos ciclos de descanso devido à conversão das terras agrícolas em pastagens ameaça a produtividade quer do babaçu quer das próprias culturas.相似文献
16.
Silvopastoral systems, which combine tree and pasture production, are more complex ecosystems than exclusively agronomic systems. Good silvopasture management should seek to increase positive interactions (or synergies) and reduce negative interactions among system components (soil, trees, grass and cattle) to increase global system productivity. Tree growth and pasture production within such systems can be optimized through appropriate species selection and fertilization. The aim of the present study, carried out over the course of 3 years, was to compare how traditional fertilisation, sewage sludge dose, and potassium affect pasture-tree competition, botanic composition and tree growth in a silvopastoral system located on agricultural land during the early years of system development. The addition of potassium is recommended for improving tree growth in silvopastoral systems with slightly acidic soil, especially if the pasture has high legume content. White clover is a good choice of species for silvopastoral systems because it promotes tree growth. Our study revealed that pasture production improved when sewage sludge was used as a fertiliser, but annual production was still more strongly dependent on weather conditions. 相似文献
17.
Intercropping alleys in agroforestry provides an income source until the tree crop produces harvestable yields. However, cultivation
of annual crops decreases soil organic matter and increases soil erosion potential, especially on sloping landscapes. Perennial
crops maintain a continuous soil cover, increase water infiltration, reduce soil erosion, and improve overall soil quality.
The objective of this on-farm study was to assess the effects of a perennial legume, kura clover (Trifolium ambiguum M. Bieb.), on soil quality in a recently established pecan (Carya illinoinensis Wangenh. C. Koch) orchard. The pecan-kura clover agroforestry practice was established on deep loess soils of the Missouri
River hills landscape. These silt loams are on 2–20% slopes and can be highly erosive. Kura clover, introduced as the alley
crop 5 years after pecan planting, was selected based on its perennial growth habit, nitrogen-fixing ability, winter hardiness,
high forage quality, and soil conservation properties. Kura clover was seeded in 2001 and harvested for hay annually beginning
2003. Soil quality indicators of total organic C, total N, water-stable aggregates, and selected soil enzymes were determined
on surface soil samples collected annually after kura clover establishment. Soil organic C and activities of soil enzymes
increased compared with cultivated and grass pasture control soils by the eighth year of establishment. Water-stable aggregation
improved by 50% and surface soil shear strength improved significantly (P < 0.05) in alleys compared with control sites. Results illustrate that kura clover as the alley-cropped component improved
soil fertility and biological activity through increased organic matter and improved soil structure, and yielded high quality
forage valuable for the cattle-feeding operation. Kura clover maintained or improved soil quality, reduced soil erosion potential,
and benefited pecan growth by providing a source of soil nitrogen and improving soil structure for adequate water infiltration
and aeration. 相似文献
18.
19.
Silvopasture is considered a sustainable agroforestry practice as a result of benefits the system offers for biodiversity, economic returns, and environmental quality. However, little is known about temporal and spatial dynamics of forage species composition of pastures being converted to silvopasture. Research objectives were to determine (1) the response of forage species composition to a young longleaf pine (Pinus palustris Mill.)-bahiagrass (Paspalum notatum Flugge) silvopasture versus open bahiagrass pasture, and (2) the impact that alley position relative to trees has on forage species composition in a young longleaf pine-bahiagrass silvopasture. The research was conducted in a randomized complete block design with three replications from 2003 to 2007 at Americus, Georgia, USA in a longleaf-pine silvopasture established in 2000 in an existing bahiagrass pasture and an adjoining bahiagrass open-pasture. Silvopasture forage-species composition was measured within alleys. Plant community diversity was greater in the silvopasture versus open-pasture early in the growing season, but open-pasture had greater diversity during the later growing season. Alley position in silvopasture also had a significant effect on understory forage species composition. This study indicated that conversion of bahiagrass pasture to longleaf-pine silvopasture in the Southern Coastal Plain can influence plant-community characteristics by the time trees are six to seven years old. 相似文献
20.
Celia A. Harvey Cristobal Villanueva Rene Gómez Jorge Martinez 《Forest Ecology and Management》2011,261(10):1664-1674
Trees dispersed in pastures are a prominent feature of many Central American landscapes, particularly in cattle producing regions where farmers retain trees to serve as shade, fodder, timber and firewood. The presence of dispersed trees in pastures is often considered as important for the conservation of biodiversity by providing habitat and enhancing landscape connectivity. However, despite their critical productive and environmental roles, little is known about tree distribution within pastures or how farmers’ management decisions influence the trees themselves and their impact on farm productivity and biodiversity conservation. Here, we present a synthesis of (a) the abundance, composition, and size of dispersed trees in four important cattle producing regions of Costa Rica (Caňas and Río Frío) and Nicaragua (Rivas and Matiguás), based on inventory of 18,669 trees on 1492 ha of pasture, (b) the local knowledge, management and use of trees by cattle farmers, and (c) opportunities for ensuring sustainable management of dispersed trees in pasture-dominated landscapes. Dispersed trees were common in all four landscapes, with mean frequency ranging from 8.0 trees ha−1 in Caňas to 33.4 trees ha−1 in Matiguás. A total of 255 tree species were found in pastures across the four landscapes. The total number of tree species per landscape varied from 72 in Rivas to 101 in Caňas and Rio Frio, with mean species richness per farm ranging from 22.9 in Rio Frio to 45.9 in Matiguás. In all four landscapes, a handful of tree species dominated the pastures, with the ten most abundant species in each landscape accounting for >70% of all trees recorded. Most of these common tree species provide fruits or foliage eaten by cattle, or are important timber or firewood species, and are deliberately retained by farmers for these uses. In all four landscapes, farmers had a detailed knowledge of tree attributes affecting pasture and animal productivity, and influenced tree cover through pasture management activities and occasional tree cutting. Current farm management practices are gradually decreasing the diversity of trees in pastures, and in some cases also tree density, reducing their contribution to farm productivity and biodiversity conservation. To reverse this trend, incentives are required to encourage cattle farmers to retain and enhance tree cover in pastures, through the adoption of pasture management practices that favor the regeneration and persistence of a diverse range of tree species. 相似文献