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1.
In the Zona da Mata of Minas Gerais State, Brazil, family farmers are adjusting to agroecological principles to reconcile
sustainable agriculture, livelihood improvements and biodiversity conservation. Starting in 1993, experimentation with coffee
agroforestry was gradually initiated on an increasing number of farms (37 in total), resulting in the simultaneous management
of sun coffee (SC) and agroforestry coffee (AF) plots. We aimed (1) to identify factors that determine the farmers’ selection
of trees used in AF; (2) to describe the agroecological farms in transition; and (3) to perform an economic comparison between
AF and SC. These objectives were addressed by combining data from botanical surveys in 1993/1994 and 2007, by interviews with
farmers and by detailed data on the production value and costs of labour and material inputs. The results showed considerable
diversity in farming strategies and management among the farmers. Early adopters of AF had diversified towards production
of different marketable products. The use of native trees in AF for this purpose, and for restoration of soil fertility (e.g.,
leguminous trees), had increased since the start of the experiments, while exotic tree species were eliminated. Over a period
of 12 years AF was more profitable than SC due to the production of a diversity of agricultural goods, despite somewhat higher
establishment costs. Other ecosystem services delivered by AF, such as biodiversity and cultural services are currently not
valorized. Payment schemes for environmental services could further improve the economic benefits of AF for family farmers
and alleviate establishment and learning costs. 相似文献
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Ângela Maria Quintão Lana Regina Maria Quintão Lana Ernane Miranda Lemes Guilherme Lanna Reis Gustavo Henrique Ferreira Abreu Moreira 《Agroforestry Systems》2018,92(2):415-424
Silvopastoral systems (SPSs) are considered a conservationist system by combining forestry species cultivation with domesticated grazing animals, intercropping trees, and pasture in the same area. SPSs are noun for its contribution to improve soil chemical and physical properties, enhance grass nutritional status, provide healthier animal environment, and increase farmers’ options to maximize the use of land. In soil degraded areas, such as those found in Brazilian savannah biome (BSB), the SPSs constitute an alternative to soil recuperation in these areas. Therefore, our aim was to assess soil fertility attributes at different depths on a BSB grown with Brachiaria brizantha cv. Marandu grass, the influence of SPS with native tree zeyheria (Zeyheria tuberculosa) settled in 1984, or with the exotic eucalyptus (Eucalyptus grandis) settled in 1994. The soil water pH, P, Ca, Mg, and K contents, as well as soil base sum and saturation, were found superior mostly at the top layer (0–2 cm) of the eucalyptus site, than for the ipê-felpudo site. This response was correlated to greater soil organic matter and carbon at the eucalyptus site, which demonstrated to have high nutrient cycling rates. Around 50 % of the CEC in both SPSs was occupied by bases, demonstrating that the areas have large potential to absorb applied nutrients. The SPSs have no significant impact on S-SO4 2? or micronutrient availability. The litter composition in eucalyptus site was accountable for the superior results of this SPS, which has shown as a promising choice for land use and conservation in the BSB. 相似文献
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Ana Maria G. Teixeira Britaldo S. Soares-Filho Simone R. Freitas Jean Paul Metzger 《Forest Ecology and Management》2009
The dynamics of the Atlantic Rainforest loss and recovery are still not fully understood despite its long history of human occupation. In this study, we investigated changes in an Atlantic Rainforest region due to major biophysical and human proximate causes. First, we modeled land-cover and land-use changes from 1962 to 2000, including deforestation and forest regrowth, and thereby simulated future landscape trajectories to assess their possible effects on the conservation of forest species of the Ibiúna Plateau, a region located in Southeastern Brazil within the Atlantic Rainforest biome. We modeled four scenarios (status quo, random, lawenforcement, and land-use intensification) and simulated their resulting landscape trajectories for the year 2019 using DINAMICA. The landscape dynamics in the study region were particularly intense. During the first period of 1962–1981, the rate of forest regrowth (3% year−1) was greater than the rate of deforestation (2% year−1), whereas in the latter period of 1981–2000, increasing urbanization and the spreading of rural establishments resulted in more deforestation (2.9% year−1) than regrowth (1% year−1). These dynamics imprinted a heterogeneous landscape, leading to the predominance of progressively younger secondary forests with increasingly less capacity of hosting sensitive forest species. The influence of proximate causes on the dynamics of deforestation and forest regrowth showed consistent patterns, such as higher forest regrowth rates near rivers, on steep slopes and far from dirt roads, whereas losses in young secondary vegetation and forest were far from rivers, on gentle slopes and near urban areas. Of the modeled scenarios, only the law enforcement scenario may lead to the recovery of a network of interconnected forest patches, suggesting that simply the enforcement of current forest laws, which prohibit deforestation on unsuitable agricultural areas and along river margins and establish a minimum of 20% of forest remnant per rural property, may effectively favor forest species conservation in the short term (two decades) without the need of any forest restoration effort. 相似文献
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Fine-root dynamics (diameter < 2.0 mm) were studied on-farm in associations of Coffea arabica with Eucalyptus deglupta or Terminalia ivorensis and in a pseudo-chronosequence of C. arabica-E. deglupta associations (two, three, four and five years old). Coffee plants were submitted to two fertilisation types. Cores were taken
in the 0–40 cm soil profile two years after out-planting and subsequently in the following year in depth layers 0–10 and 10–20
cm, during and at the end of the rainy season, and during the dry season. Fine root density of coffee and timber shade trees
was greater in the coffee fertilisation strip as compared to unfertilised areas close to the plants or in the inter-rows.
Coffee fine roots were more evenly distributed in the topsoil (0–20 cm) whereas tree fine roots were mostly found in the first
10 cm. Although the two tree species had approximately the same fine root length density, lower coffee / tree fine root length
density ratios in T. ivorensis suggest that this shade tree is potentially a stronger competitor with coffee than E. deglupta. Coffee and tree fine root length density for 0–10 cm measured during the rainy season increased progressively from two to
five-year-aged associations and coffee fine root length density increased relatively more than E. deglupta fine root length density in the four and five-year-aged plantations suggesting that contrary to expectations, coffee fine
roots were displacing tree fine roots. 相似文献
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本文对混种大豆的落叶松.大豆、水曲柳-大豆复合生态系统土壤理化性质进行研究。结果表明,在一个生长季内混种后的土壤物理性质得到了改善。落叶松.大豆与水曲柳一大豆复合生态系统的土壤容重为1.112g/cm3和1.058g/cm3均低于相对应的纯林:混种大豆后土壤总孔隙度增加。两种林-豆复合生态系统土壤有机质分别比对应纯林高1.77倍和1.09倍:落叶松一大豆复合生态系统全氮和水解氮含量分别高于落叶松纯林4.2%和53.0/%,水曲柳-大豆复合生态系统全氮和水解氮含量分别高于水曲柳纯林75.5%和3.3%:混种大豆后全磷含量降低,而有效磷含量则增加:落叶松-大豆复合生态系统全钾和有效钾比落叶松纯林高0.6%和17.5%,水曲柳-大豆复合生态系统全钾和有效钾分别比水曲柳纯林高56.4%和21.8%。图1表3参27。 相似文献
7.
Mattana Efisio Peguero Brígido Di Sacco Alice Agramonte Wilvin Encarnación Castillo Wilkin Rafael Jiménez Francisco Clase Teodoro Pritchard Hugh W. Gómez-Barreiro Pablo Castillo-Lorenzo Elena Terrero Encarnación Marianny Way Michael J. García Ricardo Ulian Tiziana 《New Forests》2020,51(4):705-721
New Forests - Native trees from the Caribbean were tested for seed desiccation responses, by adapting the “100-seed test” protocol. Ninety-seven seed lots of 91 species were collected... 相似文献
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The intercropping system of tree with soybean in juvenile plantations, as a short-term practice, was applied at Lao Shan Experimental
Station in Mao’er Shan Forest of Northeast Forestry University, Harbin, China. The larch (Larix gmelinii)/soybean (Glycine max.) and ash (Fraxinus mandshurica) intercropping systems were studied in the field to assess the effects of the intercropping on soil physicochemical properties.
The results showed that soil physical properties were improved after soybean intercropping with larch and ash in one growing
season. The soil bulk density in larch/soybean and ash/soybean systems was 1.112 g·cm−3 and 1.058 g·cm−3, respectively, which was lower than that in the pure larch or ash plantation without intercropping. The total soil porosity
also increased after intercropping. The organic matter amount in larch/soybean system was 1.77 times higher than that in the
pure larch plantation, and it was 1.09 times higher in ash/soybean system than that in the pure ash plantation. Contents of
total nitrogen and hydrolyzable nitrogen in larch/soybean system were 4.2% and 53.0% higher than those in the pure larch stand.
Total nitrogen and hydrolyzable nitrogen contents in ash/soybean system were 75.5% and 3.3% higher than those in the pure
ash plantation. Total phosphorus content decreased after intercropping, while change of available phosphorus showed an increasing
trend. Total potassium and available potassium contents in the larch/soybean system were 0.6% and 17.5% higher than those
in the pure larch stand. Total potassium and available potassium contents in the ash/soybean system were 56.4% and 21.8% higher
than those in the pure ash plantation.
Biography: FAN A-nan (1972–), female, Ph. Doctor in Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, P. R.
China. 相似文献
9.
Trade-offs analysis for possible timber-based agroforestry scenarios using native trees in the Philippines 总被引:1,自引:2,他引:1
To assess possible new agroforestry scenarios the tree–soil–crop interaction model in agroforestry systems (WaNuLCAS 3.01)
was used based on-site specific data collected from Tabango (Central Philippines). Three native timber trees (Shorea contorta Vid., Pterocarpus indicus Juss., and Vitex parviflora Willd.) and one widely spread exotic specie (Swietenia macrophylla King.) were simulated under different intercrop scenarios with maize (Zea mays L.) and subsequently compared. Model simulation results quantified and explained trade-off between tree and crop. For example,
higher tree densities will lead to a loss of crop yield that is approximately proportional to the gain in wood volume. However,
beside this trade-off effect, there is considerable scope for tree intercropping advantage under a fertilization scenario,
with systems that yield about 50% of the maximum tree biomass still allowing 70% of monoculture maize yield. Maximum tree
yield can still be obtained at about 20% of the potential crop yield but intermediate tree population densities (400 trees ha−1) and the resulting larger stem diameters may be preferable over the larger total tree biomass obtained at higher tree densities.
Another advantage from intercropping systems is that trees directly benefit from the inputs (i.e., fertilizer) that are applied
to the crops. The three native trees species studied have different performance in relation to productivity but are similar
to (or even better than) S. macrophylla. 相似文献
10.
Agroforestry options as a means of promoting reforestation were testedby establishing with 10 farmers simple comparisons between pure plantations andtimber trees with annual or perennial intercrops. Two year-old intercroppedtrees on-farm had 22–48% greater height and 24–38% greater diameterthan trees in pure plantations. The exception was Cordiaalliodora that did not respond significantly to intercropping withcassava (Manihot esculenta). Only intercrops with the mostvaluable crops on agricultural soils produced a return to labour above thedailywage rate. On non-agricultural soils, farmers only intercrop a small area oftheir plantations with subsistence crops to meet home consumption needs. In thecontext of Costa Rica intercropping appeared to have a limited potential tofinance the reforestation costs of farmers. 相似文献
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该文报道了利用遮荫指数和遮荫程度 ,描述华北平原农区杨粮间作系统毛白杨对农田的遮荫情况。结果说明 ,毛白杨幼林 (株行距 3m× 2 m× 18m ) 1~ 7a生的遮荫指数为 1.3%~6 7..8% ,遮荫程度是 0 .3%~ 16 .5% ;中龄林至成林 (株行距 4 m× 30 m) 10~ 14a生的遮荫指数是51.3%~ 76 .0 % ,遮荫程度为 2 2 .8%~ 2 8.1%。利用遮荫程度表示林木对农田的遮荫情况比用遮荫指数更符合实际 ,并且提出 15%的遮荫程度是田间可接受的最大遮荫程度 相似文献
13.
Edivânia M. G. Duarte Irene M. Cardoso Thomas Stijnen Maria Alice F. C. Mendonça Marino S. Coelho Reinaldo B. Cantarutti Thomas W. Kuyper Ecila M. A. Villani Eduardo S. Mendonça 《Agroforestry Systems》2013,87(4):835-847
Aiming to support the use of native species from the Atlantic Rainforest in local agroforestry systems, we analysed chemical and biochemical components related to leaf decomposition of Inga subnuda, Senna macranthera, Erythrina verna, Luehea grandiflora, Zeyheria tuberculosa, Aegiphila sellowiana, and Persea americana. These tree species are native (except for P. americana) and commonly used in agroforestry systems in the Atlantic Rainforest. For the three first species (Fabaceae), we also analysed the remaining dry matter and released nutrients from leaves, using litter bags, and biological nitrogen fixation, using Bidens pilosa and Brachiaria plantaginea as references of non-N2-fixing plants. Leaves from I. subnuda, L. grandiflora, and P. americana had a lower decomposition rate than the other species, exhibiting negative correlations with lignin/N and (lignin+polyphenol)/N ratios. The percentages of remaining dry matter after 1 year were 69 % (I. subnuda), 26 % (S. macranthera) and 16 % (E. verna). Higher nutrient release was found in decreasing order from residues of E. verna, S. macranthera, and I. subnuda. The percentages of nitrogen fixation were 22.6 % (E. verna), 20.6 % (I. subnuda) and 16.6 % (S. macranthera). Diversification of tree species in agroforestry systems allows for input of diversified organic material and can contribute to maintaining and improving soil functions resulting in improvements of soil quality. 相似文献
14.
G. Bazzigher 《Forest Pathology》1981,11(4):199-207
This paper reviews initiation and execution of the selection program for blight-resistant chestnut trees in Switzerland. Important information about predisposition, resistance, and inoculation methods gained during the preliminary studies forms the basis for selection and interpretation of test results. During the last 25 years over 120000 native and Asian chestnut trees and their hybrids were tested in inoculation experiments. Now about 40000 of the selected trees are being further tested in gene banks and are being subjected to additional selection procedures. 相似文献
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A survey to identify ophiostomatoid fungi that infect wounds on native Norwegian and Swedish broadleaved trees was undertaken during summer 2004. A fungus resembling a species of Sporendocladia was commonly isolated from the exposed cambium and inner bark of wounds. Morphological examination and comparisons of DNA sequence data for the ITS and 5.8S regions of the rRNA gene region led to its identification as Sporendocladia bactrospora. Pathogenicity trials on young Populus tremula and Betula pubescens trees showed that S. bactrospora is capable of causing lesions on these trees. There have been few previous reports of S. bactrospora, and in most cases, these have been as saprophytes on wood. In contrast, results of this study show that it is a common inhabitant of freshly made wounds on native broadleaved trees in Scandinavia, and it appears to contribute to staining of wood. 相似文献
18.
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
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