Science.gov

Sample records for reforestation agroforestry practices

  1. Agroforestry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The impacts of agroforestry systems (AFS) on soil management in temperate, subtropical, and tropical biomes support the beneficial, holistic role of tree components in agricultural land-use systems. Compared to annual monocultures, AFS can enhance several soil physical properties improving soil resi...

  2. Agroforestry practices, runoff, and nutrient loss: a paired watershed comparison.

    PubMed

    Udawatta, Ranjith P; Krstansky, J John; Henderson, Gray S; Garrett, Harold E

    2002-01-01

    A paired watershed study consisting of agroforestry (trees plus grass buffer strips), contour strips (grass buffer strips), and control treatments with a corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotation was used to examine treatment effects on runoff, sediment, and nutrient losses. During the (1991-1997) calibration and subsequent three-year treatment periods, runoff was measured in 0.91- and 1.37-m H-flumes with bubbler flow meters. Composite samples were analyzed for sediment, total phosphorus (TP), total nitrogen (TN), nitrate, and ammonium. Calibration equations developed to predict runoff, sediment, and nutrients losses explained 66 to 97% of the variability between treatment watersheds. The contour strip and agroforestry treatments reduced runoff by 10 and 1% during the treatment period. In both treatments, most runoff reductions occurred in the second and third years after treatment establishment. The contour strip treatment reduced erosion by 19% in 1999, while erosion in the agroforestry treatment exceeded the predicted loss. Treatments reduced TP loss by 8 and 17% on contour strip and agroforestry watersheds. Treatments did not result in reductions in TN during the first two years of the treatment period. The contour strip and agroforestry treatments reduced TN loss by 21 and 20%, respectively, during a large precipitation event in the third year. During the third year of treatments, nitrate N loss was reduced 24 and 37% by contour strip and agroforestry treatments. Contour strip and agroforestry management practices effectively reduced nonpoint-source pollution in runoff from a corn-soybean rotation in the clay pan soils of northeastern Missouri. PMID:12175039

  3. Farmers, the Practice of Farming and the Future of Agroforestry: An Application of Bourdieu's Concepts of Field and Habitus

    ERIC Educational Resources Information Center

    Raedeke, Andrew H.; Green, John J.; Hodge, Sandra S.; Valdivia, Corinne

    2003-01-01

    Agroforestry, the practice of raising crops and trees together in ways that are mutually beneficial, provides farmers with an alternative to more conventional farming practices. In this paper, we apply Bourdieu's concepts of "field" and "habitus" in an attempt to better understand the practice of farming and the role that agroforestry may have in…

  4. Impacts of public policies and farmer preferences on agroforestry practices in Kerala, India.

    PubMed

    Guillerme, S; Kumar, B M; Menon, A; Hinnewinkel, C; Maire, E; Santhoshkumar, A V

    2011-08-01

    Agroforestry systems are fundamental features of the rural landscape of the Indian state of Kerala. Yet these mixed species systems are increasingly being replaced by monocultures. This paper explores how public policies on land tenure, agriculture, forestry and tree growing on private lands have interacted with farmer preferences in shaping land use dynamics and agroforestry practices. It argues that not only is there no specific policy for agroforestry in Kerala, but also that the existing sectoral policies of land tenure, agriculture, and forestry contributed to promoting plantation crops, even among marginal farmers. Forest policies, which impose restrictions on timber extraction from farmers' fields under the garb of protecting natural forests, have often acted as a disincentive to maintaining tree-based mixed production systems on farmlands. The paper argues that public policies interact with farmers' preferences in determining land use practices. PMID:21461959

  5. Impacts of Public Policies and Farmer Preferences on Agroforestry Practices in Kerala, India

    NASA Astrophysics Data System (ADS)

    Guillerme, S.; Kumar, B. M.; Menon, A.; Hinnewinkel, C.; Maire, E.; Santhoshkumar, A. V.

    2011-08-01

    Agroforestry systems are fundamental features of the rural landscape of the Indian state of Kerala. Yet these mixed species systems are increasingly being replaced by monocultures. This paper explores how public policies on land tenure, agriculture, forestry and tree growing on private lands have interacted with farmer preferences in shaping land use dynamics and agroforestry practices. It argues that not only is there no specific policy for agroforestry in Kerala, but also that the existing sectoral policies of land tenure, agriculture, and forestry contributed to promoting plantation crops, even among marginal farmers. Forest policies, which impose restrictions on timber extraction from farmers' fields under the garb of protecting natural forests, have often acted as a disincentive to maintaining tree-based mixed production systems on farmlands. The paper argues that public policies interact with farmers' preferences in determining land use practices.

  6. Village agroforestry systems and tree-use practices: A case study in Sri Lanka. Multipurpose tree species network research series

    SciTech Connect

    Wickramasinghe, A.

    1992-01-01

    Village agroforestry systems in Sri Lanka have evolved through farmers' efforts to meet their survival needs. The paper examines farmers' land-use systems and their perceptions of the role of trees in the villages of Bambarabedda and Madugalla in central Sri Lanka. The benefits of village agroforestry are diverse food, fuelwood, fodder, timber, and mulch, but food products are of outstanding importance. The ability of Artocarpus heterophyllus (the jackfruit tree) and Cocos nucifera (coconut) to ensure food security during the dry season and provide traditional foods throughout the year, as well as to grow in limited space, make them popular crops in the two study villages. The study recommends that further research precede the formulation of agricultural interventions and that efforts to promote improved tree varieties recognize farmers' practices and expressed needs.

  7. VARIATIONS IN SOIL AGGREGATE STABILITY AND ENZYME ACTIVITIES IN A TEMPERATE AGROFORESTRY PRACTICE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agroforestry and grass buffers have been shown to improve soil properties and overall environmental quality. The objective of this study was to examine management and landscape effects on water stable soil aggregates (WSA), soil carbon, soil nitrogen, enzyme activity, and microbial community DNA co...

  8. AGROFORESTRY SYSTEMS: INTEGRATED LAND USE TO STORE AND CONSERVE CARBON

    EPA Science Inventory

    Agroforestry is a promising land use practice to maintain or increase agricultural productivity while preserving or improving fertility. n extensive literature survey was conducted to evaluate the carbon dynamics of agroforestry practices and to assess their potential to store ca...

  9. Agroforestry Practices Promote Biodiversity and Natural Resource Diversity in Atlantic Nicaragua.

    PubMed

    Sistla, Seeta A; Roddy, Adam B; Williams, Nicholas E; Kramer, Daniel B; Stevens, Kara; Allison, Steven D

    2016-01-01

    Tropical forest conversion to pasture, which drives greenhouse gas emissions, soil degradation, and biodiversity loss, remains a pressing socio-ecological challenge. This problem has spurred increased interest in the potential of small-scale agroforestry systems to couple sustainable agriculture with biodiversity conservation, particularly in rapidly developing areas of the tropics. In addition to providing natural resources (i.e. food, medicine, lumber), agroforestry systems have the potential to maintain higher levels of biodiversity and greater biomass than lower diversity crop or pasture systems. Greater plant diversity may also enhance soil quality, further supporting agricultural productivity in nutrient-limited tropical systems. Yet, the nature of these relationships remains equivocal. To better understand how different land use strategies impact ecosystem services, we characterized the relationships between plant diversity (including species richness, phylogenetic diversity, and natural resource diversity), and soil quality within pasture, agroforests, and secondary forests, three common land use types maintained by small-scale farmers in the Pearl Lagoon Basin, Nicaragua. The area is undergoing accelerated globalization following the 2007 completion of the region's first major road; a change which is expected to increase forest conversion for agriculture. However, farmer agrobiodiversity maintenance in the Basin was previously found to be positively correlated with affiliation to local agricultural NGOs through the maintenance of agroforestry systems, despite these farmers residing in the communities closest to the new road, highlighting the potential for maintaining diverse agroforestry agricultural strategies despite heightened globalization pressures. We found that agroforestry sites tended to have higher surface soil %C, %N, and pH relative to neighboring to secondary forest, while maintaining comparable plant diversity. In contrast, pasture reduced

  10. Interactive effects among ecosystem services and management practices on crop production: Pollination in coffee agroforestry systems

    PubMed Central

    Boreux, Virginie; Kushalappa, Cheppudira G.; Vaast, Philippe; Ghazoul, Jaboury

    2013-01-01

    Crop productivity is improved by ecosystem services, including pollination, but this should be set in the context of trade-offs among multiple management practices. We investigated the impact of pollination services on coffee production, considering variation in fertilization, irrigation, shade cover, and environmental variables such as rainfall (which stimulates coffee flowering across all plantations), soil pH, and nitrogen availability. After accounting for management interventions, bee abundance improved coffee production (number of berries harvested). Some management interventions, such as irrigation, used once to trigger asynchronous flowering, dramatically increased bee abundance at coffee trees. Others, such as the extent and type of tree cover, revealed interacting effects on pollination and, ultimately, crop production. The effects of management interventions, notably irrigation and addition of lime, had, however, far more substantial positive effects on coffee production than tree cover. These results suggest that pollination services matter, but managing the asynchrony of flowering was a more effective tool for securing good pollination than maintaining high shade tree densities as pollinator habitat. Complex interactions across farm and landscape scales, including both management practices and environmental conditions, shape pollination outcomes. Effective production systems therefore require the integrated consideration of management practices in the context of the surrounding habitat structure. This paper points toward a more strategic use of ecosystem services in agricultural systems, where ecosystem services are shaped by the coupling of management interventions and environmental variables. PMID:23671073

  11. Interactive effects among ecosystem services and management practices on crop production: pollination in coffee agroforestry systems.

    PubMed

    Boreux, Virginie; Kushalappa, Cheppudira G; Vaast, Philippe; Ghazoul, Jaboury

    2013-05-21

    Crop productivity is improved by ecosystem services, including pollination, but this should be set in the context of trade-offs among multiple management practices. We investigated the impact of pollination services on coffee production, considering variation in fertilization, irrigation, shade cover, and environmental variables such as rainfall (which stimulates coffee flowering across all plantations), soil pH, and nitrogen availability. After accounting for management interventions, bee abundance improved coffee production (number of berries harvested). Some management interventions, such as irrigation, used once to trigger asynchronous flowering, dramatically increased bee abundance at coffee trees. Others, such as the extent and type of tree cover, revealed interacting effects on pollination and, ultimately, crop production. The effects of management interventions, notably irrigation and addition of lime, had, however, far more substantial positive effects on coffee production than tree cover. These results suggest that pollination services matter, but managing the asynchrony of flowering was a more effective tool for securing good pollination than maintaining high shade tree densities as pollinator habitat. Complex interactions across farm and landscape scales, including both management practices and environmental conditions, shape pollination outcomes. Effective production systems therefore require the integrated consideration of management practices in the context of the surrounding habitat structure. This paper points toward a more strategic use of ecosystem services in agricultural systems, where ecosystem services are shaped by the coupling of management interventions and environmental variables. PMID:23671073

  12. Impacts of climate change on soil erosion in Portuguese watersheds with contrasting Mediterranean climates and agroforestry practices

    NASA Astrophysics Data System (ADS)

    Nunes, J. P.; Lima, J. C.; Bernard-Jannin, L.; Veiga, S.; Rodríguez-Blanco, M. L.; Sampaio, E.; Batista, D. P.; Zhang, R.; Rial-Rivas, M. E.; Moreira, M.; Santos, J. M.; Keizer, J. J.; Corte-Real, J.

    2012-04-01

    Climate change in Mediterranean regions could lead to higher winter rainfall intensity and, due to higher climatic aridity, lower vegetation cover. This could lead to increasing soil erosion rates, accelerating ongoing soil degradation and desertification processes. Adaptation to these scenarios would have costs and benefits associated with soil protection but also agroforestry production and water usage. This presentation will cover project ERLAND, which is studying these impacts for two headwater catchments (<1000 ha) in Portugal, located in distinct climatic conditions within the Mediterranean climate area, and their land-use practices are adapted to these conditions. The Macieira de Alcoba catchment in northern Portugal has a wet Mediterranean climate (1800 mm/yr, but with a dry summer season). The high rainfall allows the plantation of fast growing tree species (pine and eucalypt) in the higher slopes, and the irrigation of corn in the lower slopes. Forest fires are a recurring problem, linked with the high biomass growth and the occurrence of a dry season. Potential impacts of climate change include less favorable conditions for eucalypt growth, higher incidence of wildfires, and less available water for summer irrigation, all of which could lead to lower vegetation cover. The Guadalupe catchment in southern Portugal has a dry Mediterranean climate (700 mm/yr, falling mostly in winter). The land-use is montado, an association between sclerophyllous oaks (cork and holm oaks) and annual herbaceous plans (winter wheat or pasture). The region suffers occasional severe droughts; climate change has the potential to increase the frequency and severity of these droughts, leading to lower vegetation cover and, potentially, limiting the conditions for cork and holm oak growth. Each catchment has been instrumented with erosion measurement plots and flow and turbidity measurements at the outlet, together with surveys of vegetation and soil properties; measurements in

  13. Research issues: A prospectus for agroforestry

    SciTech Connect

    Hinds, W.T.

    1989-04-01

    Considerable progress is visible in both the concepts and practice of agroforestry projects, over the past few decades. In such circumstances, what might be a useful approach to structure further research or investigations At least three characteristics come to mind that merit consideration: complexity of the phenomena, criteria for priorities, and choices constrained by resource scarcity. In the next few paragraphs, these three topics will briefly examined. Significant research issues for agroforestry remain urgent, but they tend to be generally site-specific in nature in comparison with other disciplines of field-related research. This site-specific characteristic tends to Balkanize scientific attention, so that choices for research effort reflect local perceptions, and perhaps dilute attention to the overall importance of agroforestry as an investigative disciplines. Furthermore, these issues are notorious for their ecological complexity, so this aspect will be the first to be examined. 23 refs.

  14. Synergy of agroforestry and bottomland hardwood afforestation

    USGS Publications Warehouse

    Twedt, D.J.; Portwood, J.

    2003-01-01

    Afforestation of bottomland hardwood forests has historically emphasized planting heavy-seeded tree species such as oak (Quercus spp.) and pecan (Caryaillinoensis) with little or no silvicultural management during stand development. Slow growth of these tree species, herbivory, competing vegetation, and limited seed dispersal, often result in restored sites that are slow to develop vertical vegetation structure and have limited tree diversity. Where soils and hydrology permit, agroforestry can provide transitional management that mitigates these historical limitations on converting cropland to forests. Planting short-rotation woody crops and intercropping using wide alleyways are two agroforestry practices that are well suited for transitional management. Weed control associated with agroforestry systems benefits planted trees by reducing competition. The resultant decrease in herbaceous cover suppresses small mammal populations and associated herbivory of trees and seeds. As a result, rapid vertical growth is possible that can 'train' under-planted, slower-growing, species and provide favorable environmental conditions for naturally invading trees. Finally, annual cropping of alleyways or rotational pulpwood harvest of woody crops provides income more rapidly than reliance on future revenue from traditional silviculture. Because of increased forest diversity, enhanced growth and development, and improved economic returns, we believe that using agroforestry as a transitional management strategy during afforestation provides greater benefits to landowners and to the environment than does traditional bottomland hardwood afforestation.

  15. Improving the issuing, absorption and use of climate forecast information in agroforestry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agroforestry includes a range of practices that combine partial canopies of perennial woody vegetation (trees, shrubs, or hedges) with below-canopy production of forages, arable crops, fruits, berries, and nuts, herbs, or medicinal plants. Agroforestry systems can be broadly grouped into windbreaks ...

  16. Soil quality indicators of a mature alley-cropping agroforestry system in temperate North America

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although agroforestry practices are believed to improve soil quality, reports on long-term effects of alley cropping on soils within agroforestry in the temperate zone are limited. The objective of this study was to examine effects of management, landscape, and soil depth of an established agrofores...

  17. Agroforestry buffers for nonpoint source pollution reductions from agricultural watersheds.

    PubMed

    Udawatta, Ranjith P; Garrett, Harold E; Kallenbach, Robert

    2011-01-01

    Despite increased attention and demand for the adoption of agroforestry practices throughout the world, rigorous long-term scientific studies confirming environmental benefits from the use of agroforestry practices are limited. The objective was to examine nonpoint-source pollution (NPSP) reduction as influenced by agroforestry buffers in watersheds under grazing and row crop management. The grazing study consists of six watersheds in the Central Mississippi Valley wooded slopes and the row crop study site consists of three watersheds in a paired watershed design in Central Claypan areas. Runoff water samples were analyzed for sediment, total nitrogen (TN), and total phosphorus (TP) for the 2004 to 2008 period. Results indicate that agroforestry and grass buffers on grazed and row crop management sites significantly reduce runoff, sediment, TN, and TP losses to streams. Buffers in association with grazing and row crop management reduced runoff by 49 and 19%, respectively, during the study period as compared with respective control treatments. Average sediment loss for grazing and row crop management systems was 13.8 and 17.9 kg ha yr, respectively. On average, grass and agroforestry buffers reduced sediment, TN, and TP losses by 32, 42, and 46% compared with the control treatments. Buffers were more effective in the grazing management practice than row crop management practice. These differences could in part be attributed to the differences in soils, management, and landscape features. Results from this study strongly indicate that agroforestry and grass buffers can be designed to improve water quality while minimizing the amount of land taken out of production. PMID:21546665

  18. Short rotation woody crops: Using agroforestry technology for energy in the United States

    SciTech Connect

    Wright, L L; Ranney, J W

    1991-01-01

    Agroforestry in the United States is being primarily defined as the process of using trees in agricultural systems for conservation purposes and multiple products. The type of agroforestry most commonly practiced in many parts of the world, that is the planting of tree crops in combination with food crops or pasture, is the type least commonly practiced in the United States. One type of agroforestry technique, which is beginning now and anticipated to expand to several million acres in the United States, is the planting of short-rotation woody crops (SRWCs) primarily to provide fiber and fuel. Research on SRWC's and environmental concerns are described.

  19. Short rotation woody crops: Using agroforestry technology for energy in the United States

    SciTech Connect

    Wright, L.L.; Ranney, J.W.

    1991-12-31

    Agroforestry in the United States is being primarily defined as the process of using trees in agricultural systems for conservation purposes and multiple products. The type of agroforestry most commonly practiced in many parts of the world, that is the planting of tree crops in combination with food crops or pasture, is the type least commonly practiced in the United States. One type of agroforestry technique, which is beginning now and anticipated to expand to several million acres in the United States, is the planting of short-rotation woody crops (SRWCs) primarily to provide fiber and fuel. Research on SRWC`s and environmental concerns are described.

  20. Greenhouse gas emissions in an agroforestry system in the southeastern U.S.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agroforestry systems can provide diverse ecosystem services and economic benefits that conventional farming practices cannot. Importantly, these systems have the potential to mitigate greenhouse gas emissions by reducing the need for external inputs, enhancing nutrient cycling and promoting C seques...

  1. A Paired watershed Evaluation of Agroforestry effects on Water Quality on a Corn/Soybean Rotation

    NASA Astrophysics Data System (ADS)

    Udawatta, Ranjith; Jose, Shibu; Garrett, Harold

    2015-04-01

    Rigorous long-term scientific studies confirming environmental benefits from the use of agroforestry practices are limited and thus limit the adoption of agroforestry practices throughout the world. The objective of the study was to examine non point source pollution (NPSP) reduction by agroforestry buffers in row-crop watersheds. The study consists of three watersheds in a paired watershed design in Knox County, Missouri, USA. Watersheds were established in 1991 and treatments of agroforestry (trees+grass) and grass buffers were established on two watersheds in 1997 after a 7-year calibration period. Runoff water samples were analyzed for sediment, total nitrogen (TN) and total phosphorus (TP) for the 2009 to 2010 period. Results indicated that agroforestry and grass buffers on row crop watersheds significantly reduce runoff, sediment, TN, and TP losses to streams. Buffers in association with row crop management reduced runoff by 26% during the study period as compared to the control treatments. Average sediment loss for row crop management and buffer watersheds was 14.8 and 9.7 kg ha-1 yr-1 respectively. On average, grass and agroforestry buffers reduced sediment, TN, and TP losses by 32, 42, and 46% compared to the control treatments. These differences could in part be attributed to the differences in management, soils, and landscape features. Results from this study strongly indicate that agroforestry and grass buffers can be implemented to reduce NPSP to water bodies while improving land value and environmental quality.

  2. Parklands Partnership: Education through Reforestation.

    ERIC Educational Resources Information Center

    Scalia, Josephine A.

    1992-01-01

    Describes New York City's Parklands Partnership Program, in which elementary and secondary students visit natural woodlands areas in their neighborhood, learn about forest ecology, and engage in restoration and reforestation activities that foster a connection between themselves and their local environment. (SV)

  3. Reforesting the Earth. Worldwatch Paper 83.

    ERIC Educational Resources Information Center

    Postel, Sandra; Heise, Lori

    This document deals with efforts aimed at reforesting large areas of degraded lands. It includes sections on: (1) tree cover trends; (2) fuelwood challenges of the future; (3) the need to supply industrial wood; (4) stabilizing soil and water resources; (5) forests and climate change; and (6) mobilization for reforestation. (TW)

  4. Agroforestry Systems In Poland A Preliminary Identification

    NASA Astrophysics Data System (ADS)

    Borek, Robert

    2015-01-01

    This paper seeks to use state-of-the-art knowledge to depict the foundations and prospects for agroforestry systems in Poland to develop, in line with political, legal, historical and environmental conditions pertaining in the country. The main legal provisions concerning the presence of trees in agriculture are presented prior to a first-ever defining of key traditional agroforestry systems in Poland.

  5. Forest management and agroforestry to sequester and conserve atmospheric carbon dioxide

    SciTech Connect

    Schriwder, P.E.; Dixon, R.K.; Winjum, J.K.

    1993-01-01

    As part of the Global Change Research Program of the United States Environmental Protection Agency (USEPA), an assessment was initiated in 1990 to evaluate forest establishment and management options to sequester carbon and reduce the accumulation of greenhouse gases in the atmosphere. Three specific objectives are to: identify site-suitable technologies and practices that could be utilized to manage forests and agroforestry systems to sequester and conserve carbon; assess available data on site-level costs of promising forest and agroforestry management practices; evaluate estimates of technically suitable land in forested nations and biomes of the world to help meet the Noordwijk forestation targets.

  6. Reforestation of bottomland hardwoods and the issue of woody species diversity

    USGS Publications Warehouse

    Allen, J.A.

    1997-01-01

    Bottomland hardwood forests in the southcentral United States have been cleared extensively for agriculture, and many of the remaining forests are fragmented and degraded. During the last decade, however, approximately 75,000 ha of land-mainly agricultural fields-have been replanted or contracted for replanting, with many more acres likely to be reforested in the near future. The approach used in most reforestation projects to date has been to plant one to three overstory tree species, usually Quercus spp. (oaks), and to rely on natural dispersal for the establishment of other woody species. I critique this practice by two means. First, a brief literature review demonstrates that moderately high woody species diversity occurs in natural bottomland hardwood forests in the region. This review, which relates diversity to site characteristics, serves as a basis for comparison with stands established by means of current reforestation practices. Second, I reevaluate data on the invasion of woody species from an earlier study of 10 reforestation projects in Mississippi,with the goal of assessing the likelihood that stands with high woody species diversity will develop. I show that natural invasion cannot always be counted on to produce a diverse stand, particularly on sites more than about 60 m from an existing forest edge. I then make several recommendations for altering current reforestation pactices in order to establish stands with greater woody species diversity, a more natural appearance,and a more positive environmental impact at scales larger than individual sites.

  7. Establishment report: Reforestation of the Pen Branch corridor and delta

    SciTech Connect

    Nelson, E.A.; Dulohery, N.J.; Bunton, C.S.; Trettin, C.C.; McKee, W.H. Jr.

    1995-12-01

    This report documents the role of the USDA Forest Service in the reforestation of the Pen Branch floodplain and delta. The report focuses upon the reforestation activities and monitoring to characterize the sites.

  8. Impact of agroforestry plantings for bioenergy production on soil organic carbon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tree windbreaks are an attractive multiple-benefit land use through their ability to mitigate climate change by modifying the local microclimate to improve crop growth and by sequestering carbon in the soil and tree biomass. Recently, such agroforestry practices are also being considered for their b...

  9. Forecasting the Performance of Agroforestry Systems

    NASA Astrophysics Data System (ADS)

    Luedeling, E.; Shepherd, K.

    2014-12-01

    Agroforestry has received considerable attention from scientists and development practitioners in recent years. It is recognized as a cornerstone of many traditional agricultural systems, as well as a new option for sustainable land management in currently treeless agricultural landscapes. Agroforestry systems are diverse, but most manifestations supply substantial ecosystem services, including marketable tree products, soil fertility, water cycle regulation, wildlife habitat and carbon sequestration. While these benefits have been well documented for many existing systems, projecting the outcomes of introducing new agroforestry systems, or forecasting system performance under changing environmental or climatic conditions, remains a substantial challenge. Due to the various interactions between system components, the multiple benefits produced by trees and crops, and the host of environmental, socioeconomic and cultural factors that shape agroforestry systems, mechanistic models of such systems quickly become very complex. They then require a lot of data for site-specific calibration, which presents a challenge for their use in new environmental and climatic domains, especially in data-scarce environments. For supporting decisions on the scaling up of agroforestry technologies, new projection methods are needed that can capture system complexity to an adequate degree, while taking full account of the fact that data on many system variables will virtually always be highly uncertain. This paper explores what projection methods are needed for supplying decision-makers with useful information on the performance of agroforestry in new places or new climates. Existing methods are discussed in light of these methodological needs. Finally, a participatory approach to performance projection is proposed that captures system dynamics in a holistic manner and makes probabilistic projections about expected system performance. This approach avoids the temptation to take

  10. Assessing Local Knowledge Use in Agroforestry Management with Cognitive Maps

    NASA Astrophysics Data System (ADS)

    Isaac, Marney E.; Dawoe, Evans; Sieciechowicz, Krystyna

    2009-06-01

    Small-holder farmers often develop adaptable agroforestry management techniques to improve and diversify crop production. In the cocoa growing region of Ghana, local knowledge on such farm management holds a noteworthy role in the overall farm development. The documentation and analysis of such knowledge use in cocoa agroforests may afford an applicable framework to determine mechanisms driving farmer preference and indicators in farm management. This study employed 12 in-depth farmer interviews regarding variables in farm management as a unit of analysis and utilized cognitive mapping as a qualitative method of analysis. Our objectives were (1) to illustrate and describe agroforestry management variables and associated farm practices, (2) to determine the scope of decision making of individual farmers, and (3) to investigate the suitability of cognitive mapping as a tool for assessing local knowledge use. Results from the cognitive maps revealed an average of 16 ± 3 variables and 19 ± 3 links between management variables in the farmer cognitive maps. Farmer use of advantageous ecological processes was highly central to farm management (48% of all variables), particularly manipulation of organic matter, shade and food crop establishment, and maintenance of a tree stratum as the most common, highly linked variables. Over 85% of variables included bidirectional arrows, interpreted as farm management practices dominated by controllable factors, insofar as farmers indicated an ability to alter most farm characteristics. Local knowledge use on cocoa production revealed detailed indicators for site evaluation, thus affecting farm preparation and management. Our findings suggest that amid multisourced information under conditions of uncertainty, strategies for adaptable agroforestry management should integrate existing and localized management frameworks and that cognitive mapping provides a tool-based approach to advance such a management support system.

  11. 26 CFR 1.194-1 - Amortization of reforestation expenditures.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 3 2010-04-01 2010-04-01 false Amortization of reforestation expenditures. 1....194-1 Amortization of reforestation expenditures. (a) In general. Section 194 allows a taxpayer to elect to amortize over an 84-month period, up to $10,000 of reforestation expenditures (as defined...

  12. Reducing pollution in agriculture land, agroforestry and Common Agrarian Policy

    NASA Astrophysics Data System (ADS)

    Rosa Mosquera Losada, Maria; Santiago-Freijanes, José Javier; Ferreiro-Domínguez, Nuria; Rois, Mercedes; Rigueiro-Rodríguez, Antonio

    2015-04-01

    Reducing non-point source pollution in Europe is a key activity for the European institutions and citizens. Ensuring high quality food supply while environment is sustainable managed is a highly relevant in the European agriculture. New CAP tries to promote sustainability with the greening measures in Pillar I (EU payments) and Pillar II (EU-Country cofinanced payments). The star component of the Pillar I is the greening. The greening includes three types of activities related to crop rotation, maintenance of permanent pasture and the promotion of Ecological Focus Areas (EFA). Greening practices are compulsory in arable lands when they are placed in regions with low proportion of forests and when the owner has large farms. Among the EFA, there are several options that include agroforestry practices like landscape features, buffer strips, agroforestry, strips of eligible hectares along forest edges, areas with short rotation coppice. These practices promote biodiversity and the inclusion of woody vegetation that is able to increase the uptake of the excess of nutrients like N or P. USA Agriculture Department has also recognize the importance of woody vegetation around the arable lands to reduce nutrient pollution and promote biodiversity.

  13. CARBON STORAGE BENEFITS OF AGROFORESTRY SYSTEMS

    EPA Science Inventory

    The process of land degradation is a local phenomenon that occurs field by field but also has a global dimension because of the sheer extent at which it is taking place. groforestry represents a link between the local and global scales. rom the farmer's perspective, agroforestry ...

  14. Agroforestry planting design affects loblolly pine growth

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of plantation design on resource utilization has not been adequately investigated in agroforestry plantations. An experiment was conducted near Booneville, AR on a silt loam soil with a fragipan. Loblolly pine trees were planted in 1994 in an east-west row orientation in three designs: ...

  15. Evaluation of reforested areas using LANDSAT imagery

    NASA Technical Reports Server (NTRS)

    Dejesusparada, N. (Principal Investigator); Filho, P. H.; Shimabukuro, Y. E.

    1978-01-01

    The author has identified the following significant results. Visual and automatic interpretation of LANDSAT imagery was used to classify the general Pinus and Eucalyptus according to their age and species. A methodology was derived, based on training areas, to define the legend and spectral characteristics of the analyzed classes. Imager analysis of the training areas show that Pinus taeda is separable from the other Pinus species based on JM distance measurement. No difference of JM measurements was observed among Eucalyptus species. Two classes of Eucalyptus were separated according to their ages: those under and those over two years of age. Channel 6 and 7 were suitable for the discrimination of the reforested classes. Channel 5 was efficient to separated reforested areas from nonforested targets in the region. The automatic analysis shows the highest classification precision was obtained for Eucalyptus over two years of age (95.12 percent).

  16. Reforesting "bare hills" in Vietnam: social and environmental consequences of the 5 million hectare reforestation program.

    PubMed

    McElwee, Pamela

    2009-09-01

    In recent years, forestry has been strongly promoted by the government of the Socialist Republic of Vietnam through large-scale projects to rehabilitate and reforest millions of hectares of land. One project to reforest 5 million hectares has received hundreds of millions of US dollars for implementation. Yet based on a case study in one area of northern Vietnam, this project appears to have had a number of unforeseen consequences. Large areas of land classified as "bare hills" have been targeted for reforestation, despite the fact that these lands already harbor a number of species that were used by local communities. The bare hills were especially economically important to poor households and to women who collected a variety of nontimber forest products there. Because the reforestation project focused most efforts on establishing new plantations rather than supporting natural regeneration, diverse sources of non-timber forest products were being replaced with monocrop exotic tree plantations. A strong inequity in the allocation of private lands for reforestation has characterized the regreening projects to date, and this may have continuing unwelcome social, environmental, and economic impacts into the future, particularly for the poor. PMID:19860156

  17. Reforestation trials in the Russian Far East

    SciTech Connect

    Lowery, R.F. ); Perevertailo, I. )

    1994-12-01

    Enormous areas of primary forest in Russia have been and continue to be destroyed by fire and harvesting. Most all of these areas have been left to reforest naturally. Little reforestation by planting has been attempted and these efforts have met with limited success. Consequently vast areas are without forest cover. Weyerhaeuser Company initiated cooperative forest planting trials in the Russian Far East (RFE) in 1989. Seeds from the RFE were used to produce high quality containerized seedlings in the US. These seedlings were then used in research plantings trials in 1991 and 1992, near Vanino and Khabarovsk. A large-scale operational planting project was carried out in 1993. Seedling survival and growth has been excellent over a wide range of sites. The operational planting results demonstrate that high quality seedlings can be used to successfully reforest sites that have been burned or harvested in the RFE. Key to the operational planting success was good logistical support and a well trained, organized and positively motivated work force.

  18. Tradeoffs between income, biodiversity, and ecosystem functioning during tropical rainforest conversion and agroforestry intensification.

    PubMed

    Steffan-Dewenter, Ingolf; Kessler, Michael; Barkmann, Jan; Bos, Merijn M; Buchori, Damayanti; Erasmi, Stefan; Faust, Heiko; Gerold, Gerhard; Glenk, Klaus; Gradstein, S Robbert; Guhardja, Edi; Harteveld, Marieke; Hertel, Dietrich; Höhn, Patrick; Kappas, Martin; Köhler, Stefan; Leuschner, Christoph; Maertens, Miet; Marggraf, Rainer; Migge-Kleian, Sonja; Mogea, Johanis; Pitopang, Ramadhaniel; Schaefer, Matthias; Schwarze, Stefan; Sporn, Simone G; Steingrebe, Andrea; Tjitrosoedirdjo, Sri S; Tjitrosoemito, Soekisman; Twele, André; Weber, Robert; Woltmann, Lars; Zeller, Manfred; Tscharntke, Teja

    2007-03-20

    Losses of biodiversity and ecosystem functioning due to rainforest destruction and agricultural intensification are prime concerns for science and society alike. Potentially, ecosystems show nonlinear responses to land-use intensification that would open management options with limited ecological losses but satisfying economic gains. However, multidisciplinary studies to quantify ecological losses and socioeconomic tradeoffs under different management options are rare. Here, we evaluate opposing land use strategies in cacao agroforestry in Sulawesi, Indonesia, by using data on species richness of nine plant and animal taxa, six related ecosystem functions, and on socioeconomic drivers of agroforestry expansion. Expansion of cacao cultivation by 230% in the last two decades was triggered not only by economic market mechanisms, but also by rarely considered cultural factors. Transformation from near-primary forest to agroforestry had little effect on overall species richness, but reduced plant biomass and carbon storage by approximately 75% and species richness of forest-using species by approximately 60%. In contrast, increased land use intensity in cacao agroforestry, coupled with a reduction in shade tree cover from 80% to 40%, caused only minor quantitative changes in biodiversity and maintained high levels of ecosystem functioning while doubling farmers' net income. However, unshaded systems further increased income by approximately 40%, implying that current economic incentives and cultural preferences for new intensification practices put shaded systems at risk. We conclude that low-shade agroforestry provides the best available compromise between economic forces and ecological needs. Certification schemes for shade-grown crops may provide a market-based mechanism to slow down current intensification trends. PMID:17360392

  19. Guide to monitoring carbon storage in forestry and agroforestry projects

    SciTech Connect

    MacDicken, K.G.

    1997-10-01

    As the international Joint Implementation (JI) program develops a system for trading carbon credits to offset greenhouse gas emissions, project managers need a reliable basis for measuring the carbon storage benefits of carbon offset projects. Monitoring and verifying carbon storage can be expensive, depending on the level of scientific validity needed. This guide describes a system of cost-effective methods for monitoring and verification on a commercial basis, for three types of land use; forest plantations, managed natural forests and agroforestry. Winrock International`s Forest Carbon Monitoring Program developed this system with its partners as a way to provide reliable results using accepted principles and practices of forest inventory, soil science and ecological surveys. Perhaps most important, the system brings field research methods to bear on commercial-scale inventories, at levels of precision specified by funding agencies.

  20. Evaluation of reforestation using remote sensing techniques

    NASA Technical Reports Server (NTRS)

    Parada, N. D. J. (Principal Investigator); Filho, P. H.; Shimabukuro, Y. E.; Dossantos, J. R.

    1982-01-01

    The utilization of remotely sensed orbital data for forestry inventory. The study area (approximately 491,100 ha) encompasses the municipalities of Ribeirao Preto, Altinopolis, Cravinhos, Serra Azul, Luis Antonio, Sao Simao, Sant Rita do Passa Quatro and Santa Rosa do Viterbo (Sao Paulo State). Materials used were LANDSAT data from channels 5 and 7 (scale 1:250,000) and CCT's. Visual interpretation of the imagery showed that for 1977 a total of 37,766.00 ha and for 1979 38,003.75 ha were reforested with Pinus and Eucalyptus within the area under study. The results obtained show that LANDSAT data can be used efficiently in forestry inventory studies.

  1. Estimating reforestation by means of remote sensing

    NASA Technical Reports Server (NTRS)

    Dejesusparada, N. (Principal Investigator); Filho, P. H.; Shimabukuro, Y. E.; Dossantos, J. R.

    1981-01-01

    LANDSAT imagery at the scale of 1:250.000 and obtained from bands 5 and 7 as well as computer compatible tapes were used to evaluate the effectiveness of remotely sensed orbital data in inventorying forests in a 462,100 area of Brazil emcompassing the cities of Ribeirao, Altinopolis Cravinhos, Serra Azul, Luis Antonio, Sao Simao, Santa Rita do Passa Quatro, and Santa Rosa do Viterbo. Visual interpretation of LANDSAT imagery shows that 37,766 hectares (1977) and 38,003.75 hectares (1979) were reforested areas of pine and eucalyptus species. An increment of 237.5 hectares was found during this two-year time lapse.

  2. The future role of reforestation in reducing buildup of atmospheric CO{sub 2}

    SciTech Connect

    Marland, G.

    1993-12-31

    Among the options posed for mitigating the buildup of atmospheric CO{sub 2} is planting new forest areas to sequester carbon from the atmosphere. Among the questions of interest in modeling the global carbon cycle is the extent to which reforestation is likely to succeed in providing physical removal of CO{sub 2} from the atmosphere. There are many strategies for using forest land to mitigate the atmospheric buildup of CO{sub 2}: decreasing the rate at which forests are cleared for other land uses, increasing the density of carbon storage in existing forests, improving the rate and efficiency at which forest products are used in the place of other energy intensive products, substitution of renewable wood fuels for fossil fuels, improved management of forests and agroforestry, and increasing the amount of land in standing forest. Because increasing the area of forests has social, political, and economic limitations; in addition to physical limitations; it is hard to envision a large increase in forest area except where there are associated economic benefits. The authors speculation is that, over the next several decades, the forest strategies most likely to be pursued for the express purpose of CO{sub 2} mitigation are those which provide more or more-efficient substitution of forest products for energy or energy-intensive resources and that the physical accumulation of additional carbon in forests will be of lesser importance.

  3. Avian response to bottomland hardwood reforestation: the first 10 years

    USGS Publications Warehouse

    Twedt, D.J.; Wilson, R.R.; Henne-Kerr, J.L.; Grosshuesch, D.A.

    2002-01-01

    Bttomland hardwood forests were planted on agricultural fields in Mississippi and Louisiana using either predominantly Quercus species (oaks) or Populus deltoides (eastern cottonwood). We assessed avian colonization of these reforested sites between 2 and 10 years after planting. Rapid vertical growth of cottonwoods (circa 2 - 3 m / yr) resulted in sites with forest structure that supported greater species richness of breeding birds, increased Shannon diversity indices, and supported greater territory densities than on sites planted with slower-growing oak species. Grassland birds (Spiza americana [Dickcissel], and Sturnella magna [Eastern Meadowlark]) were indicative of species breeding on oak-dominated reforestation # 10 years old. Agelaius phoeniceus (Red-winged Blackbird) and Colinus virginianus (Northern Bobwhite) characterized cottonwood reforestation # 4 years old, whereas 14 species of shrub-scrub birds (e.g., Passerina cyanea [Indigo Bunting]) and early-successional forest birds (e.g., Vireo gilvus [Warbling Vireo]) typified cottonwood reforestation 5 to 9 years after planting. Rates of daily nest survival did not differ between reforestation strategies. Nest parasitism increased markedly in older cottonwood stands, but was overwhelmed by predation as a cause of nest failure. Based on Partners in Flight prioritization scores and territory densities, the value of cottonwood reforestation for avian conservation was significantly greater than that of oak reforestation during their first 10 years. Because of benefits conferred on breeding birds, we recommend reforestation of bottomland hardwoods include a high proportion of fast-growing, early successional species such as cottonwood.

  4. Opportunities for biodiversity gains under the world's largest reforestation programme.

    PubMed

    Hua, Fangyuan; Wang, Xiaoyang; Zheng, Xinlei; Fisher, Brendan; Wang, Lin; Zhu, Jianguo; Tang, Ya; Yu, Douglas W; Wilcove, David S

    2016-01-01

    Reforestation is a critical means of addressing the environmental and social problems of deforestation. China's Grain-for-Green Program (GFGP) is the world's largest reforestation scheme. Here we provide the first nationwide assessment of the tree composition of GFGP forests and the first combined ecological and economic study aimed at understanding GFGP's biodiversity implications. Across China, GFGP forests are overwhelmingly monocultures or compositionally simple mixed forests. Focusing on birds and bees in Sichuan Province, we find that GFGP reforestation results in modest gains (via mixed forest) and losses (via monocultures) of bird diversity, along with major losses of bee diversity. Moreover, all current modes of GFGP reforestation fall short of restoring biodiversity to levels approximating native forests. However, even within existing modes of reforestation, GFGP can achieve greater biodiversity gains by promoting mixed forests over monocultures; doing so is unlikely to entail major opportunity costs or pose unforeseen economic risks to households. PMID:27598524

  5. Agroforestry Systems in Zimbabwe: Promoting Trees in Agriculture.

    ERIC Educational Resources Information Center

    Vukasin, Helen L., Ed.

    Agroforestry has been defined as a sustainable crop management system which combines the production of forest crops with field crops. In June, 1987, an agroforestry workshop took place in Nyanga, Manicaland, Zimbabwe. This document was prepared to share the information presented at this workshop with other non-government organizations around the…

  6. Engaging in School-Led Multisectoral Collaboration: Implications to Agroforestry Promotion in the Philippine Uplands

    ERIC Educational Resources Information Center

    Landicho, Leila D.; Cabahug, Rowena D.; De Luna, Catherine C.

    2009-01-01

    The Agroforestry Support Program for Empowering Communities Towards Self-Reliance (ASPECTS) was conceived to develop a model of two-stage approach in agroforestry promotion by capacitating the upland communities to establish community-managed agroforestry extension services, while strengthening the agroforestry education programs of the three…

  7. Socio-economic comparison between traditional and improved cultivation methods in agroforestry systems, East Usambara Mountains, Tanzania.

    PubMed

    Reyes, Teija; Quiroz, Roberto; Msikula, Shija

    2005-11-01

    The East Usambara Mountains, recognized as one of the 25 most important biodiversity hot spots in the world, have a high degree of species diversity and endemism that is threatened by increasing human pressure on resources. Traditional slash and burn cultivation in the area is no longer sustainable. However, it is possible to maintain land productivity, decrease land degradation, and improve rural people's livelihood by ameliorating cultivation methods. Improved agroforestry seems to be a very convincing and suitable method for buffer zones of conservation areas. Farmers could receive a reasonable net income from their farm with little investment in terms of time, capital, and labor. By increasing the diversity and production of already existing cultivations, the pressure on natural forests can be diminished. The present study shows a significant gap between traditional cultivation methods and improved agroforestry systems in socio-economic terms. Improved agroforestry systems provide approximately double income per capita in comparison to traditional methods. More intensified cash crop cultivation in the highlands of the East Usambara also results in double income compared to that in the lowlands. However, people are sensitive to risks of changing farming practices. Encouraging farmers to apply better land management and practice sustainable cultivation of cash crops in combination with multipurpose trees would be relevant in improving their economic situation in the relatively short term. The markets of most cash crops are already available. Improved agroforestry methods could ameliorate the living conditions of the local population and protect the natural reserves from human disturbance. PMID:16261277

  8. Impacts of Bokashi on survival and growth rates of Pinus pseudostrobus in community reforestation projects.

    PubMed

    Jaramillo-López, P F; Ramírez, M I; Pérez-Salicrup, D R

    2015-03-01

    Community-based small-scale reforestation practices have been proposed as an alternative to low-efficiency massive reforestations conducted by external agents. These latter conventional reforestations are often carried out in soils that have been seriously degraded and this has indirectly contributed to the introduction of non-native species and/or acceptance of very low seedling survival rates. Bokashi is a fermented soil organic amendment that can be made from almost any available agricultural byproduct, and its beneficial effects in agriculture have been reported in various contexts. Here, we report the results of a community-based small-scale experimental reforestation where the provenance of pine seedlings (local and commercial) and the use of Bokashi as a soil amendment were evaluated. Bokashi was prepared locally by members of a small rural community in central Mexico. Almost two years after the establishment of the trial, survival rates for the unamended and amended local trees were 97-100% while survival of the commercial trees from unamended and amended treatments were 87-93%. Consistently through time, local and commercial seedlings planted in Bokashi-amended soils were significantly taller (x̅ = 152 cm) than those planted in unamended soils (̅x = 86 cm). An unplanned infection by Cronartium quercuum in the first year of the experiment was considered as a covariable. Infected seedlings showed malformations but this did not affect survival and growth rates. Bokashi amendment seems as an inexpensive, locally viable technology to increase seedling survival and growth and to help recover deforested areas where soils have been degraded. This allows local stakeholders to see more rapid results while helping them to maintain their interest in conservation activities. PMID:25460423

  9. Agro-ecosystem and socio-economic role of homegarden agroforestry in Jabithenan District, North-Western Ethiopia: implication for climate change adaptation.

    PubMed

    Linger, Ewuketu

    2014-01-01

    Homegarden agroforestry is believed to be more diverse and provide multiple services for household than other monocropping system and this is due to the combination of crops, trees and livestock. The aim of this study was to assess socio-economic and agro-ecological role of homegardens in Jabithenan district, North-western Ethiopia. Two sites purposively and two villages randomly from each site were selected. Totally 96 households; in which 48 from homegarden agroforestry user and 48 from non-tree based garden user were selected for this study. Socio-economic data and potential economic and agro-ecosystem role of homegarden agroforestry over non-tree based garden were collected by using semi-structured and structured questionnaires to the households. Homegarden agroforestry significantly (P < 0.05) improved the farmers cash income than non-tree based garden. With insignificant garden size; homegarden agroforestry practice provides good socio-economical and agro-ecological service for farmers which have a higher implication for climate change adaptation than non-tree based garden. PMID:24790810

  10. Determinants of bacterial communities in Canadian agroforestry systems.

    PubMed

    Banerjee, Samiran; Baah-Acheamfour, Mark; Carlyle, Cameron N; Bissett, Andrew; Richardson, Alan E; Siddique, Tariq; Bork, Edward W; Chang, Scott X

    2016-06-01

    Land-use change is one of the most important factors influencing soil microbial communities, which play a pivotal role in most biogeochemical and ecological processes. Using agroforestry systems as a model, this study examined the effects of land uses and edaphic properties on bacterial communities in three agroforestry types covering a 270 km soil-climate gradient in Alberta, Canada. Our results demonstrate that land-use patterns exert stronger effects on soil bacterial communities than soil zones in these agroforestry systems. Plots with trees in agroforestry systems promoted greater bacterial abundance and to some extent species richness, which was associated with more nutrient-rich soil resources. While Acidobacteria, Actinobacteria and Alphaproteobacteria were the dominant bacterial phyla and subphyla across land uses, Arthrobacter, Acidobacteria_Gp16, Burkholderia, Rhodanobacter and Rhizobium were the keystone taxa in these agroforestry systems. Soil pH and carbon contents emerged as the major determinants of bacterial community characteristics. We found non-random co-occurrence and modular patterns of soil bacterial communities, and these patterns were controlled by edaphic factors and not their taxonomy. Overall, this study highlights the drivers and co-occurrence patterns of soil microbial communities in agroforestry systems. PMID:26184386

  11. Monitoring of reforested areas using LANDSAT data. [Ribas do Rio Pardo, Mato Grosso do Sul, Brazil

    NASA Technical Reports Server (NTRS)

    Dejesusparada, N. (Principal Investigator); Filho, P. H.; Shimabukuro, Y. E.

    1981-01-01

    Imagery obtained with channels 5 and 7 was visually interpreted in an effort to determine the spatial, spectral, and temporal characteristics of a 105,000 hectare area of Fazenda Mutum which was reforested with various species of pine and eucalyptus. It was possible to map a reforested area as small as 6 hectare in its initial implantation using contrast with the surrounding targets. Five classes were mapped: nondeforested areas, partially deforested areas, deforested areas, partially reforested areas, and fully reforested areas. In 1979, 12,000 hectare were deforested, 4,330.83 hectare were partially reforested, and 42,744.71 hectare were reforested.

  12. Effects of reforestation, deforestation, and afforestation on carbon storage in soils.

    PubMed

    Czimczik, Claudia I; Mund, Martina; Schulze, Ernst-Detlef; Wirth, Christian

    2005-01-01

    This study reviews the effects of changes in land use and land management on SOC pools in forest soils. In the 1990s, deforestation remained the most important land-use change in tropical regions (-142 x 10(6) ha per year). In non-tropical regions the forested area increased in developed countries as a result of natural reforestation (+26 x 10(6) ha per year). Deforestation also continued in under-developed countries in temperate regions. Without intensive site preparation, harvest followed by natural regeneration or reforestation has little impact on SOC pools in the mineral topsoil (0-0.3 m). Intensive site preparation results in losses of 6-13% of the initial SOC from the topsoil in the first decades. On average, deforestation followed by conversion to cropland results in SOC losses of 42% (or 0.1-1500 g (C) m(-2)) from the mineral topsoil, whereas conversion to pasture results in gains of 8%. The largest changes in SOC storage occur within the first two decades. After reforestation, SOC accumulation depends on the kind of managed forest established. Under productive deciduous reforestation (excluding eucalypts), SOC in the mineral topsoil accumulates at a rate of 20-50 g (C) m(-2) per year, and SOC pools could recover from cultivation-induced losses within 40 years. Under coniferous reforestation, the rate of accumulation of carbon is highest (95 g (C) m(-2) per year) in the organic layer, which is very susceptible to site preparation practices. In the mineral topsoil, the rate of accumulation is much lower (4 g (C) m(-2) per year), and recovery of the initial SOC pools might take several hundred years. The resulting land-use 'memory effect' has introduced large variation of the SOC pools in contemporary carbon budget studies. Thus, there seems to be a large temporal asymmetry between the period of time over which depletion of SOC occurs and the time needed for recovery of the SOC pools in the mineral soil. This should be taken into account when considering

  13. A common framework for greenhouse gas assessment protocols in temperate agroforestry systems: Connecting via GRACEnet

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agroforestry systems offer many ecosystem benefits, but such systems have previously been marginalized in temperate environments due to overriding economic goals and perceived management complexity. In view of adaptation to a changing climate, agroforestry systems offer advantages that require quan...

  14. Effect of reforestation on streamflow in central New York

    USGS Publications Warehouse

    Schneider, William Joseph; Ayer, Gordon Roundy

    1961-01-01

    Hydrologic data have been collected since 1932 in central New York State to determine the effect of reforestation on streamflow. Data are available for three small partly reforested areas and for one nonreforested control area. From 35 to 58 percent of the 3 areas were reforested, mostly with species of pine and spruce. The trees were allowed to grow without thinning or cutting, and by 1958 these reforested areas had developed into dense coniferous woodlots. Intensive statistical analyses of the data from the four study areas were made in 1958. Analyses were made for three hydrologic periods: the dormant season represented by the 6-month period ending April 30, the growing season represented by the 6-month period ending October 31, and the year represented by the 12-month period ending April 30. Analyses of the hydrologic data using multiple correlation with time as a variable and analyses of covariance between early and late periods of record indicated that several significant changes had occurred in the streamflow from the partly reforested study areas. Based on correlation with precipitation, total runoff for the dormant season from the 3 study areas was reduced by annual rates of 0.17 to 0.29 inches per year. Based on correlations with streamflow from a control area, total runoff from the partly reforested Shackham Brook area was reduced by average rates of 0.14 inches per growing season, 0.23 inches per dormant season, and 0.36 inches per hydrologic year. Peak discharges on Shackham Brook during the dormant season were reduced by 1958 by an average of 41 percent for the season, with reductions ranging from an average of 66 percent for November to an average of 16 percent for April. No significant changes were found in the peak discharges for the growing season, rates of base-flow recession, volumes of direct runoff, or annual low flows of streams in the three partly reforested areas. The significant reductions in total runoff are attributed to increases in

  15. Changes in soil physical and chemical properties in long term improved natural and traditional agroforestry management systems of cacao genotypes in Peruvian Amazon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Traditional slash and burn agriculture practiced in the Peruvian Amazon region is leading to soil degradation and deforestation of native forest flora. The only way to stop such destructive processes is through the adoptation of sustainable alternatives such as growing crops in agroforestry systems....

  16. Planning of the reforestation at abandoned coal mines using GIS

    NASA Astrophysics Data System (ADS)

    Choi, Y.; Oh, S.; Park, H.; Kwon, H.

    2009-12-01

    This study presents a prototype of decision support system for planning the reforestation at abandoned coal mines. The characteristics of deforested zone due to mine development were analyzed and categorized to define the schema of GIS database. Multiple criteria (i.e. forest-climate zone, mining method, visibility, managerial condition, slope gradient, reforestation purpose) were considered to classify the deforested zone and to assign unique IDs to the key index fields in tables. ArcMap, ArcObjects and Visual Basic.NET were used to implement the system. The application to the Samcheok coal block in Korea shows that the system could present a rational solution to select suitable trees for the reforestation and can also provide cost evaluation tools to support the environmental planning work.

  17. Incorporating agroforestry approaches into commodity value chains.

    PubMed

    Millard, Edward

    2011-08-01

    The productivity of tropical agricultural commodities is affected by the health of the ecosystem. Shade tolerant crops such as coffee and cocoa benefit from environmental services provided by forested landscapes, enabling landscape design that meets biodiversity conservation and economic needs. What can motivate farmers to apply and maintain such landscape approaches? Rather than rely on a proliferation of externally funded projects new opportunities are emerging through the international market that buys these commodities. As part of their growing commitment to sustainable supply chains, major companies are supporting agroforestry approaches and requiring producers and traders to demonstrate that the source of their commodities complies with a set of principles that conserves forested landscapes and improves local livelihoods. The paper presents examples of international companies that are moving in this direction, analyzes why and how they are doing it and discusses the impact that has been measured in coffee and cocoa communities in Latin America and Africa. It particularly considers the role of standards and certification systems as a driver of this commitment to promote profitable operations, environmental conservation and social responsibility throughout the coffee and cocoa value chains. Such approaches are already being taken to scale and are no longer operating only in small niches of the market but the paper also considers the limitations to growth in this market-based approach. PMID:21556936

  18. Incorporating Agroforestry Approaches into Commodity Value Chains

    NASA Astrophysics Data System (ADS)

    Millard, Edward

    2011-08-01

    The productivity of tropical agricultural commodities is affected by the health of the ecosystem. Shade tolerant crops such as coffee and cocoa benefit from environmental services provided by forested landscapes, enabling landscape design that meets biodiversity conservation and economic needs. What can motivate farmers to apply and maintain such landscape approaches? Rather than rely on a proliferation of externally funded projects new opportunities are emerging through the international market that buys these commodities. As part of their growing commitment to sustainable supply chains, major companies are supporting agroforestry approaches and requiring producers and traders to demonstrate that the source of their commodities complies with a set of principles that conserves forested landscapes and improves local livelihoods. The paper presents examples of international companies that are moving in this direction, analyzes why and how they are doing it and discusses the impact that has been measured in coffee and cocoa communities in Latin America and Africa. It particularly considers the role of standards and certification systems as a driver of this commitment to promote profitable operations, environmental conservation and social responsibility throughout the coffee and cocoa value chains. Such approaches are already being taken to scale and are no longer operating only in small niches of the market but the paper also considers the limitations to growth in this market-based approach.

  19. The Role of Soil Biological Function in Regulating Agroecosystem Services and Sustainability in the Quesungual Agroforestry System

    NASA Astrophysics Data System (ADS)

    Fonte, S.; Pauli, N.; Rousseau, L.; SIX, J. W. U. A.; Barrios, E.

    2014-12-01

    The Quesungual agroforestry system from western Honduras has been increasingly promoted as a promising alternative to traditional slash-and-burn agriculture in tropical dry forest regions of the Americas. Improved residue management and the lack of burning in this system can greatly impact soil biological functioning and a number of key soil-based ecosystem services, yet our understanding of these processes has not been thoroughly integrated to understand system functionality as a whole that can guide improved management. To address this gap, we present a synthesis of various field studies conducted in Central America aimed at: 1) quantifying the influence of the Quesungual agroforestry practices on soil macrofauna abundance and diversity, and 2) understanding how these organisms influence key soil-based ecosystem services that ultimately drive the success of this system. A first set of studies examined the impact of agroecosystem management on soil macrofauna populations, soil fertility and key soil processes. Results suggest that residue inputs (derived from tree biomass pruning), a lack of burning, and high tree densities, lead to conditions that support abundant, diverse soil macrofauna communities under agroforestry, with soil organic carbon content comparable to adjacent forest. Additionally, there is great potential in working with farmers to develop refined soil quality indicators for improved land management. A second line of research explored interactions between residue management and earthworms in the regulation of soil-based ecosystem services. Earthworms are the most prominent ecosystem engineers in these soils. We found that earthworms are key drivers of soil structure maintenance and the stabilization of soil organic matter within soil aggregates, and also had notable impacts on soil nutrient dynamics. However, the impact of earthworms appears to depend on residue management practices, thus indicating the need for an integrated approach for

  20. Reforestation strategies amid social instability: lessons from Afghanistan.

    PubMed

    Groninger, John W

    2012-04-01

    Foreign and domestic government agencies and other international organizations pursue reforestation programs in rural upper watershed areas of Afghanistan over the past decade to alleviate poverty, combat the insurgency and rehabilitate a depleted forest resource base. Popular programs incorporate cash-for-work to conduct hillside terracing, check dam construction and tree-planting for nut production, fuel wood, timber, dune stabilization, and erosion abatement. Programmatic approaches have varied as a function of accessibility, security and local objectives. Uncertain land tenure and use rights, weak local environmental management capacity, and a focus on agricultural production to meet immediate needs limit interest, nationally and locally. Unreliable security, a lack of high quality tree planting stock, limited technical knowledge and coordination among government agencies, and poor security hamper program expansion. Reforestation success would be most likely where these issues are least acute. The Afghan government should focus on supporting community based natural resource management, developing and disseminating improved conservation tree nursery strategies, and promoting watershed management schemes that incorporate forestry, range management and agronomic production. Reforestation practitioners could benefit from the human and material resources now present as part of the international war effort. Successes and failures encountered in Afghanistan should be considered in order to address similar problems in insecure regions elsewhere when reforestation may help reverse environmental degradation and contribute to broader social stabilization efforts. PMID:22314681

  1. INTERNATIONAL WORKSHOP ON LARGE-SCALE REFORESTATION: PROCEEDINGS

    EPA Science Inventory

    The purpose of the workshop was to identify major operational and ecological considerations needed to successfully conduct large-scale reforestation projects throughout the forested regions of the world. Large-scale" for this workshop means projects where, by human effort, approx...

  2. Reforestation Strategies Amid Social Instability: Lessons from Afghanistan

    NASA Astrophysics Data System (ADS)

    Groninger, John W.

    2012-04-01

    Foreign and domestic government agencies and other international organizations pursue reforestation programs in rural upper watershed areas of Afghanistan over the past decade to alleviate poverty, combat the insurgency and rehabilitate a depleted forest resource base. Popular programs incorporate cash-for-work to conduct hillside terracing, check dam construction and tree-planting for nut production, fuel wood, timber, dune stabilization, and erosion abatement. Programmatic approaches have varied as a function of accessibility, security and local objectives. Uncertain land tenure and use rights, weak local environmental management capacity, and a focus on agricultural production to meet immediate needs limit interest, nationally and locally. Unreliable security, a lack of high quality tree planting stock, limited technical knowledge and coordination among government agencies, and poor security hamper program expansion. Reforestation success would be most likely where these issues are least acute. The Afghan government should focus on supporting community based natural resource management, developing and disseminating improved conservation tree nursery strategies, and promoting watershed management schemes that incorporate forestry, range management and agronomic production. Reforestation practitioners could benefit from the human and material resources now present as part of the international war effort. Successes and failures encountered in Afghanistan should be considered in order to address similar problems in insecure regions elsewhere when reforestation may help reverse environmental degradation and contribute to broader social stabilization efforts.

  3. Soil properties following reforestation or afforestation of marginal cropland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reforestation or afforestation of marginal agricultural lands offers opportunities to sequester soil organic carbon (SOC) and improve the quality of degraded soils. The objectives of this study were to identify the extent and distribution of marginally productive cropland that was originally under f...

  4. Case study: Prioritization strategies for reforestation of minelands to benefit Cerulean Warblers

    USGS Publications Warehouse

    McDermott, Molly E.; Shumar, Matthew B.; Wood, Petra Bohall

    2013-01-01

    The central Appalachian landscape is being heavily altered by surface coal mining. The practice of Mountaintop Removal/Valley Fill (MTRVF) mining has transformed large areas of mature forest to non-forest and created much forest edge, affecting habitat quality for mature forest wildlife. The Appalachian Regional Reforestation Initiative is working to restore mined areas to native hardwood forest conditions, and strategies are needed to prioritize restoration efforts for wildlife. We present mineland reforestation guidelines for the imperiled Cerulean Warbler, considered a useful umbrella species, in its breeding range. In 2009, we surveyed forest predicted to have Cerulean Warblers near mined areas in the MTRVF region of West Virginia and Kentucky. We visited 36 transect routes and completed songbird surveys on 151 points along these routes. Cerulean Warblers were present at points with fewer large-scale canopy disturbances and more mature oak-hickory forest. We tested the accuracy of a predictive map for this species and demonstrated that it can be useful to guide reforestation efforts. We then developed a map of hot spot locations that can be used to determine potential habitat suitability. Restoration efforts would have greatest benefit for Cerulean Warblers and other mature forest birds if concentrated near a relative-abundance hot spot, on north- and east-facing ridgetops surrounded by mature deciduous forest, and prioritized to reduce edges and connect isolated forest patches. Our multi-scale approach for prioritizing restoration efforts using an umbrella species may be applied to restore habitat impacted by a variety of landscape disturbances.

  5. Evaluation of reforestation in the Lower Mississippi River Alluvial Valley

    USGS Publications Warehouse

    King, S.L.; Keeland, B.D.

    1999-01-01

    Only about 2.8 million ha of an estimated original 10 million ha of bottomland hardwood forests still exist in the Lower Mississippi River Alluvial Valley (LMAV) of the United States. The U.S. Fish and Wildlife Service, the U.S. Forest Service, and state agencies initiated reforestation efforts in the late 1980s to improve wildlife habitat. We surveyed restorationists responsible for reforestation in the LMAV to determine the magnitude of past and future efforts and to identify major limiting factors. Over the past 10 years, 77,698 ha have been reforested by the agencies represented in our survey and an additional 89,009 ha are targeted in the next 5 years. Oaks are the most commonly planted species and bare-root seedlings are the most commonly used planting stock. Problems with seedling availability may increase the diversity of plantings in the future. Reforestation in the LMAV is based upon principles of landscape ecology; however, local problems such as herbivory, drought, and flooding often limit success. Broad-scale hydrologic restoration is needed to fully restore the structural and functional attributes of these systems, but because of drastic and widespread hydrologic alterations and socioeconomic constraints, this goal is generally not realistic. Local hydrologic restoration and creation of specific habitat features needed by some wildlife and fish species warrant attention. More extensive analyses of plantings are needed to evaluate functional success. The Wetland Reserve Program is a positive development, but policies that provide additional financial incentives to landowners for reforestation efforts should be seriously considered.

  6. Economic principles to appraise agro-forestry projects

    SciTech Connect

    Harou, P.A.

    1983-01-01

    Basic economic principles and the classical project evaluation technique can be satisfactorily used to solve investment decisions for agroforestry projects. Recommendations made for this type of appraisal are to: concentrate on the small farm participants; study the forestry component and risk diversification; detail the externalities; and consider the cultural environment. 15 references.

  7. Cacau Cabruca Agroforestry System of Production in Bahia, Brazil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Cacao Cabruca Agroforestry system of production was developed by farmers in Southern Bahia probably in the beginning of the 19th century. To establish such system, farmers in the Atlantic rain forest region selectively maintained around 75 adult individual native trees per hectare, removed the o...

  8. Variation in Soil Enzyme Activities in a Temperate Agroforestry Watershed

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Integration of agroforestry and grass buffers into row crop watersheds improves overall environmental quality, including soil quality. The objective of this study was to examine management and landscape effects on soil carbon, soil nitrogen, microbial diversity, enzyme activity, and DNA concentrati...

  9. Agroforestry systems for bioenergy in the southeastern USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural landscapes are an important component of a biofuel strategy to develop energy independence. Agroforestry systems offer an opportunity to produce both food and biofuel feedstocks from the same land area. Such a strategy could improve numerous ecosystem services more so than either of t...

  10. Soils organic C sequestration under poplar and willow agroforestry systems

    NASA Astrophysics Data System (ADS)

    Gunina, Anna; Tariq, Azeem; Lamersdorf, Norbert

    2015-04-01

    Short rotation coppices (SRC) as monocultures or as agroforestry (AF) applications (e.g. alley cropping) are two techniques to implement forest into agricultural practices. Despite afforestation promotes soil carbon (C) accumulation, age and type of the tree stand can affect the C accumulation in different degrees. Here, we studied the impact of afforestation on C accumulation for: i) pure SCR of willow (Salix viminalis x Salix schwerinii) and poplar (Populus nigra x Populus maximowiczii) and ii) AF cropping system with willow. Forest systems have been established within the BEST agroforestry project in Germany. Adjacent agricultural field have been used as a control. Soil samples were collected in 2014, three years after plantation establishment, from three soil depths: 0-3, 3-20, and 20-30 cm. Total organic C, labile C (incubation of 20 g soil during 100 days with measuring of CO2) and aggregate structure were analysed. Additionally, density fractionation of the samples from 0-3 cm was applied to separate particulate organic matter (POM) and mineral fractions. Aggregates and density fractions were analyzed for C content. High input of plant litter as well as root exudates have led to increases of organic C in AF and SRC plots compare to cropland, mainly in the top 0-3 cm. The highest C content was found for willow SRC (18.2 g kg-1 soil), followed by willow-AF (15.6 g kg-1 soil), and poplar SRC (13.7 g kg-1 soil). Carbon content of cropland was 12.5 g kg-1 soil. Absence of ploughing caused increase portion of macroaggregates (>2000 μm) under SRC and AF in all soil layers as well as the highest percentage of C in that aggregate size class (70-80%). In contrast, C in cropland soil was mainly accumulated in small macroaggregates (250-2000 μm). Intensive mineralisation of fresh litter and old POM, taking place during first years of trees development, resulted to similar portions of free POM for willow AF, willow SRC and cropland (8%), and even lower ones for poplar

  11. Biochar application during reforestation alters species present and soil chemistry.

    PubMed

    Drake, J A; Carrucan, A; Jackson, W R; Cavagnaro, T R; Patti, A F

    2015-05-01

    Reforestation of landscapes is being used as a method for tackling climate change through carbon sequestration and land restoration, as well as increasing biodiversity and improving the provision of ecosystem services. The success of reforestation activities can be reduced by adverse field conditions, including those that reduce germination and survival of plants. One method for improving success is biochar addition to soil, which is not only known to improve soil carbon sequestration, but is also known to improve growth, health, germination and survival of plants. In this study, biochar was applied to soil at rates of 0, 1, 3 and 6 t ha(-1) along with a direct-seed forest species mix at three sites in western Victoria, Australia. Changes in soil chemistry, including total carbon, and germination and survival of species were measured over an 18 month period. Biochar was found to significantly increase total carbon by up to 15.6% on soils low in carbon, as well as alter electrical conductivity, Colwell phosphorous and nitrate- and ammonium-nitrogen. Biochar also increased the number of species present, and stem counts of Eucalyptus species whilst decreasing stem counts of Acacia species. Biochar has the potential to positively benefit reforestation activities, but site specific and plant-soil-biochar responses require targeted research. PMID:25679816

  12. Water use of agroforestry systems in semi-arid India

    SciTech Connect

    Ong, C.K.; Odongo, J.C.W.; Marshall, F.; Black, C.R.

    1992-12-31

    The increased productivity or yield advantage provided by intercropping and agroforestry systems is often attributed to the premise that mixtures of species make better use of environmental resources than when the same species are grown separately. The components complement each other because they make their major demand on resources at different times (temporal complementarity) or use resources more efficiently at a given point in time (spatial complementarity). However, mixed stands do not use resources more efficiently than sole stands when the component species compete for the same limited resources. This paper examines the evidence for interactions for physical resources in three major types of agroforestry systems, and highlights the importance of below-ground interactions, which are still poorly understood.

  13. [Research progress on carbon sink function of agroforestry system under climate change].

    PubMed

    Xie, Ting-Ting; Su, Pei-Xi; Zhou, Zi-Juan; Shan, Li-Shan

    2014-10-01

    As a land comprehensive utilization system, agroforestry system can absorb and fix CO2 effectively to increase carbon storage, and also reduces greenhouse effect convincingly while reaching the aim of harvest. The regulatory role in CO2 makes humans realize that agroforestry systems have significant superiority compared with single cropping systems, therefore, understanding the carbon sinks of different components in an agroforestry system and its influencing factors play an important role in studying global carbon cycle and accurate evaluation of carbon budget. This paper reviewed the concept and classification of agroforestry system, and then the carbon sequestration potentials of different components in agroforestry systems and influencing factors. It was concluded that the carbon sequestration rate of plants from different agroforestry systems in different regions are highly variable, ranging from 0.59 to 11.08 t C · hm(-2) · a(-1), and it is mainly influenced by climatic factors and the characteristics of agroforestry systems (species composition, tree density and stand age). The soil C sequestration of any agroforestry system is influenced by the amount and quality of biomass input provided by tree and nontree components of the system and the soil properties such as soil texture and soil structure. Overall the amount of carbon storage in any agroforestry system depends on the structure and function of its each component. The future studies should focus on the carbon sink functions of structurally optimized agroforestry systems, the temporal variation and spatial distribution pattern of carbon storage in agroforestry system and its carbon sequestration mechanism in a long time. PMID:25796917

  14. Assessment of the Adoption of Agroforestry Technologies by Limited-Resource Farmers in North Carolina

    ERIC Educational Resources Information Center

    Faulkner, Paula E.; Owooh, Bismark; Idassi, Joshua

    2014-01-01

    Agroforestry is a natural resource management system that integrates trees, forages, and livestock. The study reported here was conducted to determine farmers' knowledge about and willingness to adopt agroforestry technologies in North Carolina. The study reported participants were primarily older, male farmers, suggesting the need to attract…

  15. Potential Impacts of Climate Change on Coupled Socioecological Systems in East Africa: The Case of the Chagga Agroforestry and Maasai Agropastoralism across the Greater Environments of Mount Kilimanjaro Region

    NASA Astrophysics Data System (ADS)

    Mwangi, M. N.

    2014-12-01

    The various types of rainfall-dependent coupled socioecological systems that conspicuously characterize mountain-environments across Africa, such as the Chagga homegardens, an intensive agroforestry system, constitute a major economic backbone to the local inhabitants. Similarly, agropastoralism that characterizes the adjoining rangelands of such mountain-environments, such as that practiced by the Maasai people of Kenya, in the northern plains that adjoins Mount Kilimanjaro, is major contributor to local food security. Both Chagga agroforestry and Maasai agropastoralism also contribute greatly to broader-scale economic sectors and respectively to sustainable utilization of rangeland and mountain-environment resources. Like similar coupled socioecological systems across Africa, the Chagga agroforestry and Maasai agropastoralism are being, and will continue to be affected by the changing climate. This study uses an integrated approach to explore the sustainability of Chagga homegardens, an intensive agroforestry system, in the southern slopes of Mount Kilimanjaro in Tanzania. Concurrently, the sustainability of the Maasai agropastoralism (a livelihood-diversification type) in the northern slopes of Mount Kilimanjaro and the adjoining plains in Kenya is explored. This explication is followed by conceptualization of the potential future of Chagga agroforestry and Maasai agropastoralism systems under diverse scenarios of climate change—and alongside simultaneous effects of cross-scale social and biophysical factors, processes, and their interactions—in an integrated model. The premise of this study is that coupled socioecological systems, such as Chagga agroforestry and Maasai agropastoralism, linked to and/or dependent on mountain environments and microclimates, are natural-laboratories. Apropos this last point, the two systems offer timely insight into how similar systems in different geographical locations are likely to be influenced by the continuously changing

  16. More than Just Trees: Assessing Reforestation Success in Tropical Developing Countries

    ERIC Educational Resources Information Center

    Le, Hai Dinh; Smith, Carl; Herbohn, John; Harrison, Stephen

    2012-01-01

    Rural communities in many parts of the tropics are dependent of forests for their livelihoods and for environmental services. Forest resources in the tropics have declined rapidly over the past century and therefore many developing countries in the tropics have reforestation programs. Although reforestation is a long-term process with long-term…

  17. Volunteer Notes on Reforestation. A Handbook for Volunteers. Appropriate Technologies for Development. Reprint R-45.

    ERIC Educational Resources Information Center

    Seefeldt, Steve, Comp.

    Provided in this document are descriptions of reforestation projects and techniques presented by Peace Corps volunteers from Chad, Ivory Coast, Upper Volta, and Niger. The purpose of the document is to aid individuals in trying to find solutions to the problems facing forestry in the Sahel. These projects include: (1) reforestation of Ronier palm…

  18. Private and Social Costs of Surface Mine Reforestation Performance Criteria

    NASA Astrophysics Data System (ADS)

    Sullivan, Jay; Amacher, Gregory S.

    2010-02-01

    We study the potentially unnecessary costs imposed by strict performance standards for forest restoration of surface coal mines in the Appalachian region under the Surface Mining Control and Reclamation Act of 1977 (SMCRA) that can vary widely across states. Both the unnecessary private costs to the mine operator and costs to society (social costs) are reported for two performance standards, a ground cover requirement, and a seedling survival target. These standards are examined using numerical analyses under a range of site productivity class and market conditions. We show that a strict (90%) ground cover standard may produce an unnecessary private cost of more than 700/ha and a social cost ranging from 428/ha to 710/ha, as compared with a 70% standard. A strict tree survival standard of 1235 trees/ha, as compared with the more typical 1087 trees/ha standard, may produce an unnecessary private cost of approximately 200/ha, and a social cost in the range of 120 to 208/ha. We conclude that strict performance standards may impose substantial unnecessary private costs and social costs, that strict performance standards may be discouraging the choice of forestry as a post-mining land use, and that opportunities exist for reform of reforestation performance standards. Our study provides a basis for evaluating tradeoffs between regulatory efficiency and optimal reforestation effort.

  19. Private and social costs of surface mine reforestation performance criteria.

    PubMed

    Sullivan, Jay; Amacher, Gregory S

    2010-02-01

    We study the potentially unnecessary costs imposed by strict performance standards for forest restoration of surface coal mines in the Appalachian region under the Surface Mining Control and Reclamation Act of 1977 (SMCRA) that can vary widely across states. Both the unnecessary private costs to the mine operator and costs to society (social costs) are reported for two performance standards, a ground cover requirement, and a seedling survival target. These standards are examined using numerical analyses under a range of site productivity class and market conditions. We show that a strict (90%) ground cover standard may produce an unnecessary private cost of more than $700/ha and a social cost ranging from $428/ha to $710/ha, as compared with a 70% standard. A strict tree survival standard of 1235 trees/ha, as compared with the more typical 1087 trees/ha standard, may produce an unnecessary private cost of approximately $200/ha, and a social cost in the range of $120 to $208/ha. We conclude that strict performance standards may impose substantial unnecessary private costs and social costs, that strict performance standards may be discouraging the choice of forestry as a post-mining land use, and that opportunities exist for reform of reforestation performance standards. Our study provides a basis for evaluating tradeoffs between regulatory efficiency and optimal reforestation effort. PMID:19967364

  20. The future of reforestation programs in the tropical developing countries: insights from the Philippines

    NASA Astrophysics Data System (ADS)

    Mukul, S. A.; Herbohn, J. L.

    2013-12-01

    Reforestation against the rapid rate of deforestation and forest degradation is common in most tropical developing countries. The main objective of reforestation programs is to restore and/or enhance the degraded landscapes depreciated in environmental value. However due to changing socio-political contexts and increasing awareness on sustainable development and environmental issues such programs are becoming more challenging, particularly in the developing tropics. Like most tropical developing countries substantial deforestation has occurred in the Philippines followed by massive logging and slash-and-burn agriculture, resulting in severe social and environmental problems. The country is also one of the pioneer countries that introduces reforestation program to restore its degraded forests. Most recently the government of the Philippines has launched the National Greening Program (NGP), one of the largest reforestation projects so far, with an aim to reforest 1.5 million hectares of degraded forest in critical watersheds over a five year time period. This paper highlights the key challenges that might hinder the success of the reforestation program through National Greening Program. We found that it is unlikely to achieve the desired project goals if rural communities dependent on upland landscapes are excluded from the reforestation program through plantation establishment. Bringing larger amount of areas and greater number of people under community based forest management (CBFM) initiatives for reforestation programs, with clearly defined rights and responsibilities, as well as securing timely access to timber harvesting permits to the communities involved in maintaining the plantations could enhance the long term reforestation success in the country. The paper also tries to provide a critical review of the past reforestation efforts in the Philippines, and direction of possible research and development in order to achieve a win-win situation that will benefits

  1. Determining options for agroforestry systems for the rehabilitation of degraded watersheds in Alemaya Basin, Hararghe Highlands, Ethiopia

    SciTech Connect

    Bishaw, B.

    1993-01-01

    Deforestation, accelerated soil erosion, and land degradation are serious problems in Ethiopia. The uncontrolled removal of natural forests, demographic pressures and cyclical drought has aggravated the situation, resulting in massive environmental degradation and a serious threat to sustainable agriculture and forestry. To overcome these problems efforts have been made to launch an afforestation and conservation program; however, success to data has been limited. Thus, the main objective of this study is to find the reasons for lack of success in tree planting in the Alemaya Basin both from biophysical and socio-economic perspectives. And, based on this analysis, to propose an alternative strategy for agroforestry for the Basin. The study has identified and characterized major land uses, socio-economic constraints and agricultural and forestry practices which have limited forestry development in the Alemaya Basin. To gather the necessary information for the study, existing information sources were reviewed. Two state sampling was used for a land-use survey, and stratified random sampling for the socio-economic study. Decrease in farm size due to population increases, soil erosion, shortage of fuelwood and fodder for livestock and lack of appropriate extension service were found to be the major problems that affect sustainable production in the Alemaya Basin. Agroforestry is one of the appropriate technologies to overcome some of the problem faced by the farmers in the Alemaya Basin. The study proposed a desired state of sustainable agriculture and forestry for the Basin based on population projections, agriculture and forest products needs, and stable or improved living standards for a 20 year planning period. Alley cropping with and without fertilizers was identified as a promising agroforestry technology. Its economic feasibility was assessed by estimating costs and returns both for traditional farming and alley cropping.

  2. [Africa and the environment. Desertification and the phenomenon of drought. Deforestation and reforestation].

    PubMed

    Samake, D

    1993-04-01

    Awareness is growing throughout the world of the grave environmental damage that has been caused by human activities ad of the disastrous consequences such damage may pose for human survival. The 1992 "Earth Summit" in Rio de Janeiro marked the culmination of a series of preliminary ministerial conferences in Africa and elsewhere that called attention to practices menacing the environment. Africa's underdevelopment is at the basis of practices leading to desertification, deforestation, and pollution. The summit was of great relevance for Africa because of its recognition of the links between the environment, development, and poverty. The phenomena of drought and desertification in the Sahel are insufficiently understood. The drought began in the 1960s and has persisted irregularly into later decades. Scant rainfall may cause the useful growing season to be shorter than the minimum of 2.5-3 months needed to assure harvests. Meager vegetation, drying of domestic water sources, and the danger of erosion from violent rainstorms are among the consequences of drought. Desertification occurs when the natural vegetation is exploited excessively, when agriculture is extended into marginal lands, and when inappropriate agricultural and herding practices make the land vulnerable to erosion. Populations beset by poverty and drought engage in practices for short-term survival whose longterm consequences may be very harmful. The Sahel Institute in Bamako has outlined a regional strategy to combat desertification that calls for improving collection and conservation of surface and subsoil water, reforestation and more careful management of land and other resources, motivating local populations to assist in preventing deforestation, fertility control to lessen population pressure, and development of a database to monitor the dynamics of desertification. The European Economic community and some conservation associations have also developed conservation programs for the Sahel

  3. Humus quality after eucalypt reforestations in Asturias (Northern Spain).

    PubMed

    Cristina Zancada, M; Almendros, Gonzalo; Jiménez Ballesta, Raimundo

    2003-09-01

    The impact on soil properties of recent and ancient reforestations with Eucalyptus globulus Labill. has been studied in Cambisols and Leptosols under temperate semi-oceanic climate in Asturias (Northern Spain). Eucalypt forests showed a high potential of C accumulation in soil, mainly the ancient forest, where the organic matter concentration in the uppermost horizon (up to 415 C g x kg(-1)) was greater than in all neighbouring soil formations (climacic oak forests, up to 84 C g x kg(-1); Podsol under reforested pine forests, 287 C g x kg(-1); and Ulex shrub, 70 C g x kg(-1)). Nevertheless, there was a low concentration of available bases and a very low transformation degree of the organic matter in this eucalypt forest, only comparable to that of the Podsol. In order to analyse the major features of the biogeochemical behaviour of the sites under study, the humus fractions were isolated and the humic acid fraction was studied by derivative visible and infrared spectroscopies. Incubation experiments on whole soil samples were carried out to monitor stability against biodegradation of the organic matter under comparable conditions. In general, soils under eucalypt had a CO(2) production similar to or lower than the control sites, but the soil under the ancient eucalypt forest had a high potential for CO(2) release, similar to that of the neighbouring Podsol, what might be explained by the presence in these soils of high amounts of C accumulated in readily biodegradable forms. However, the mineralisation coefficients (CO(2) released per unit of soil C) indicated that the biodegradability of the soil humus has decreased significantly in the eucalypt-reforested sites, as it could correspond to an effective control of the biogeochemical processes caused by the antimicrobial products from the eucalypt litter. Compared to the original deciduous forests, the lower values of the E(4)/E(6) ratio in the humic acids from eucalypt forests and the lignin signature in the

  4. Effects of reforesting degraded grassland on hydrological flow pathways on Leyte, the Philippines

    NASA Astrophysics Data System (ADS)

    van Meerveld, Ilja; Zhang, Jun; Bruijnzeel, Sampurno

    2014-05-01

    Reforestation of degraded land in the tropics is promoted for a wide range of expected benefits, including carbon sequestration and streamflow regulation. However, how reforestation of degraded land affects runoff generation mechanisms and catchment water yield is still poorly understood as most experimental work pertains to non-degraded terrain. We set out to study the differences in hydrological functioning of a small degraded grassland catchment and a similar catchment that was reforested 15 years ago. Both catchments are located near Tacloban, Leyte, the Philippines. Stream stage, EC and temperature are measured continuously since June 2013. Precipitation, soil moisture content, and groundwater levels are monitored as well. Samples are taken from streamflow, precipitation, groundwater, and soil water prior to and during rainfall events for geochemical and stable isotope analysis to elucidate source contributions to storm runoff. Streamflow and event water contributions increase rapidly during almost every rainfall event in the grassland. In the reforested catchment, event water contributions to streamflow are much smaller and only increase during large events. These tracer results suggest that overland flow occurs much less frequently and is much less widespread in the reforested catchment compared to the grassland catchment. Our results thus indicate that the dominant flow pathways have changed as a result of reforestation and suggest that reforestation can largely restore the hydrological functioning of degraded sites if the forest is allowed to develop over a sufficiently long period without subsequent disturbance.

  5. Integrating climate change criteria in reforestation projects using a hybrid decision-support system

    NASA Astrophysics Data System (ADS)

    Curiel-Esparza, Jorge; Gonzalez-Utrillas, Nuria; Canto-Perello, Julian; Martin-Utrillas, Manuel

    2015-09-01

    The selection of appropriate species in a reforestation project has always been a complex decision-making problem in which, due mostly to government policies and other stakeholders, not only economic criteria but also other environmental issues interact. Climate change has not usually been taken into account in traditional reforestation decision-making strategies and management procedures. Moreover, there is a lack of agreement on the percentage of each one of the species in reforestation planning, which is usually calculated in a discretionary way. In this context, an effective multicriteria technique has been developed in order to improve the process of selecting species for reforestation in the Mediterranean region of Spain. A hybrid Delphi-AHP methodology is proposed, which includes a consistency analysis in order to reduce random choices. As a result, this technique provides an optimal percentage distribution of the appropriate species to be used in reforestation planning. The highest values of the weight given for each subcriteria corresponded to FR (fire forest response) and PR (pests and diseases risk), because of the increasing importance of the impact of climate change in the forest. However, CB (conservation of biodiversitiy) was in the third position in line with the aim of reforestation. Therefore, the most suitable species were Quercus faginea (19.75%) and Quercus ilex (19.35%), which offer a good balance between all the factors affecting the success and viability of reforestation.

  6. Estimation of future carbon budget with climate change and reforestation scenario in North Korea

    NASA Astrophysics Data System (ADS)

    Kim, Damin; Lim, Chul-Hee; Song, Cholho; Lee, Woo-Kyun; Piao, Dongfan; Heo, Seongbong; Jeon, Seongwoo

    2016-09-01

    In terms of climate change, quantifying carbon budget in forest is critical for managing a role of forest as carbon sink. Deforestation in North Korea has been exacerbating at a noticeable pace and caused to worsen the carbon budget. Under the circumstance, this study aimed to assess the impact of climate change and reforestation on the carbon budget in 2020s and 2050s, using the VISIT (Vegetation Integrative SImulator for Trace gases) model. In order to analyze the impact of reforestation, future land cover maps for the 2020s and 2050s were prepared. Among the deforested areas (2.5 × 106 ha) identified by comparing land cover maps for different periods, the potential reforestation areas were selected by a reforestation scenario considering slope, accessibility from residence, and deforestation types. The extracted potential reforestation areas were 1.7 × 106 ha and the increased forest area was spatially distributed to each district. The percentage change in carbon budget caused by climate change from the 2000s to 2020s is 67.60% and that from the 2020s to 2050s is 45.98% on average. Based on the future land cover, NEP (net ecosystem production) with reforestation will increase by 18.18% than that without reforestation in the 2050s, which shows the contribution to carbon balance. In connection with this long term projection, it is revealed that the gross fluxes such as photosynthesis and respiration may be impacted more obviously by the climate change, especially global warming, than the net carbon flux because of the offset between the changes in the gross fluxes. It is analyzed that changes in carbon budget are very sensitive to climate changes, while the impact of reforestation is relatively less sensitive. Although it is impossible to significantly improve carbon sequestration by establishing forest in a short-term, reforestation is imperative in a long-term view as it clearly has a potential mechanism to offset emitted carbon.

  7. Order No. 0020 for the establishment of methods of reforestation, 19 March 1987.

    PubMed

    1988-01-01

    In light of the "Green Movement" policy and the development of the Colombia Major National Reforestation Plan, this Order establishes the following methods of promoting reforestation: 1) advice and guidance to those concerned with tree planting; 2) forestry planning for farms; and 3) grants of trees whenever possible in the proportions indicated in the Order. The Order classifies beneficiaries into small-size tree farmers (up to 20 hectares, and 80% of whose income derives from that activity); and medium- and large-scale tree farmers (more than 20 hectares). Other provisions of the Order deal with applications, dates of completion of requirements, and the actual methods of promoting reforestation. PMID:12289472

  8. Landscape level reforestation priorities for forest breeding landbirds in the Mississippi Alluvial Valley

    USGS Publications Warehouse

    Twedt, D.J.; Uihlein, W.B., III

    2005-01-01

    Thousands of ha of cleared wetlands are being reforested annually in the Mississippi Alluvial Valley (MAV). Despite the expansive and long-term impacts of reforestation on the biological communities of the MAV, there is generally a lack of landscape level planning in its implementation. To address this deficiency we used raster-based digital data to assess the value of forest restoration to migratory landbirds for each ha within the MAV. Raster themes were developed that reflected distance from 3 existing forest cover parameters: (1) extant forest, (2) contiguous forest patches between 1,012 and 40,000 ha, and (3) forest cores with contiguous area 1 km from an agricultural, urban, or pastoral edge. Two additional raster themes were developed that combined information on the proportion of forest cover and average size of forest patches, respectively, within landscapes of 50,000, 100,000, 150,000, and 200,000 ha. Data from these 5 themes were amalgamated into a single raster using a weighting system that gave increased emphasis to existing forest cores, larger forest patches, and moderately forested landscapes while deemphasizing reforestation near small or isolated forest fragments and within largely agricultural landscapes. This amalgamated raster was then modified by the geographic location of historical forest cover and the current extent of public land ownership to assign a reforestation priority score to each ha in the MAV. However, because reforestation is not required on areas with extant forest cover and because restoration is unlikely on areas of open water and urban communities, these lands were not assigned a reforestation priority score. These spatially explicit reforestation priority scores were used to simulate reforestation of 368,000 ha (5%) of the highest priority lands in the MAV. Targeting restoration to these high priority areas resulted in a 54% increase in forest core - an area of forest core that exceeded the area of simulated reforestation

  9. Discerning fragmentation dynamics of tropical forest and wetland during reforestation, urban sprawl, and policy shifts.

    PubMed

    Gao, Qiong; Yu, Mei

    2014-01-01

    Despite the overall trend of worldwide deforestation over recent decades, reforestation has also been found and is expected in developing countries undergoing fast urbanization and agriculture abandonment. The consequences of reforestation on landscape patterns are seldom addressed in the literature, despite their importance in evaluating biodiversity and ecosystem functions. By analyzing long-term land cover changes in Puerto Rico, a rapidly reforested (6 to 42% during 1940-2000) and urbanized tropical island, we detected significantly different patterns of fragmentation and underlying mechanisms among forests, urban areas, and wetlands. Forest fragmentation is often associated with deforestation. However, we also found significant fragmentation during reforestation. Urban sprawl and suburb development have a dominant impact on forest fragmentation. Reforestation mostly occurs along forest edges, while significant deforestation occurs in forest interiors. The deforestation process has a much stronger impact on forest fragmentation than the reforestation process due to their different spatial configurations. In contrast, despite the strong interference of coastal urbanization, wetland aggregation has occurred due to the effective implementation of laws/regulations for wetland protection. The peak forest fragmentation shifted toward rural areas, indicating progressively more fragmentation in forest interiors. This shift is synchronous with the accelerated urban sprawl as indicated by the accelerated shift of the peak fragmentation index of urban cover toward rural areas, i.e., 1.37% yr-1 in 1977-1991 versus 2.17% yr-1 in 1991-2000. Based on the expected global urbanization and the regional forest transition from deforested to reforested, the fragmented forests and aggregated wetlands in this study highlight possible forest fragmentation processes during reforestation in an assessment of biodiversity and functions and suggest effective laws/regulations in land

  10. Discerning Fragmentation Dynamics of Tropical Forest and Wetland during Reforestation, Urban Sprawl, and Policy Shifts

    PubMed Central

    Gao, Qiong; Yu, Mei

    2014-01-01

    Despite the overall trend of worldwide deforestation over recent decades, reforestation has also been found and is expected in developing countries undergoing fast urbanization and agriculture abandonment. The consequences of reforestation on landscape patterns are seldom addressed in the literature, despite their importance in evaluating biodiversity and ecosystem functions. By analyzing long-term land cover changes in Puerto Rico, a rapidly reforested (6 to 42% during 1940–2000) and urbanized tropical island, we detected significantly different patterns of fragmentation and underlying mechanisms among forests, urban areas, and wetlands. Forest fragmentation is often associated with deforestation. However, we also found significant fragmentation during reforestation. Urban sprawl and suburb development have a dominant impact on forest fragmentation. Reforestation mostly occurs along forest edges, while significant deforestation occurs in forest interiors. The deforestation process has a much stronger impact on forest fragmentation than the reforestation process due to their different spatial configurations. In contrast, despite the strong interference of coastal urbanization, wetland aggregation has occurred due to the effective implementation of laws/regulations for wetland protection. The peak forest fragmentation shifted toward rural areas, indicating progressively more fragmentation in forest interiors. This shift is synchronous with the accelerated urban sprawl as indicated by the accelerated shift of the peak fragmentation index of urban cover toward rural areas, i.e., 1.37% yr−1 in 1977–1991 versus 2.17% yr−1 in 1991–2000. Based on the expected global urbanization and the regional forest transition from deforested to reforested, the fragmented forests and aggregated wetlands in this study highlight possible forest fragmentation processes during reforestation in an assessment of biodiversity and functions and suggest effective laws/regulations in

  11. Waiting for trees to grow: nest survival, brood parasitism, and the impact of reforestation efforts

    USGS Publications Warehouse

    Hazler, K.R.; Twedt, D.J.; Cooper, R.J.

    2005-01-01

    Of the forested wetlands that once covered the Mississippi Alluvial Valley, only -25% remain due to large-scale conversion to agriculture. Reforestation efforts are currently underway, but tracts planted with slow-growing oaks maintain the structure of a grassland for 5 yr or longer, and will require at least 40 yr to resemble a mature forest. Nonetheless, it is hoped that reforestation, even in early stages, can effectively increase core area in extant tracts of mature forest by reducing higher rates of nest failure and brood parasitism often associated with forest-agriculture interfaces. To test this, we monitored nests of a mature-forest specialist, the Acadian Flycatcher, in extensive bottomland forests adjacent to agricultural fields and reforested tracts (<20 yr-old). We used an information-theoretic approach to evaluate alternative hypotheses regarding the relative impacts of agriculture and reforestation in the landscape. Controlling for year, season, and stand basal area, there was little evidence that landscape context significantly affected nest survival, although survival tended to increase with decreasing amounts of agriculture. The probability of brood parasitism increased with greater proportions of open habitats in the landscape. There was much stronger support for the hypothesis that parasitism rates depended on the sum of agricultural and reforested tracts, rather than on the amount of agriculture alone. Thus, reforested tracts are not expected to have the desired effect of reducing parasitism rates in the adjacent mature forest until several decades have passed.

  12. Seasonal contrasts in the response of coffee ants to agroforestry shade-tree management.

    PubMed

    Teodoro, A V; Sousa-Souto, L; Klein, A-M; Tscharntke, T

    2010-12-01

    In many tropical landscapes, agroforestry systems are the last forested ecosystems, providing shade, having higher humidity, mitigating potential droughts, and possessing more species than any other crop system. Here, we tested the hypothesis that higher levels of shade and associated humidity in agroforestry enhance coffee ant richness more during the dry than rainy season, comparing ant richness in 22 plots of three coffee agroforestry types in coastal Ecuador: simple-shade agroforests (intensively managed with low tree species diversity), complex-shade agroforests (extensively managed with intermediate tree species diversity) and abandoned coffee agroforests (abandoned for 10-15 yr and resembling secondary forests). Seasonality affected responses of ant richness but not composition to agroforestry management, in that most species were observed in abandoned coffee agroforests in the dry season. In the rainy season, however, most species were found in simple-shade agroforests, and complex agroforestry being intermediate. Foraging coffee ants species composition did not change differently according to agroforestry type and season. Results show that shade appears to be most important in the dry seasons, while a mosaic of different land-use types may provide adequate environmental conditions to ant species, maximizing landscape-wide richness throughout the year. PMID:22182538

  13. Bats and birds increase crop yield in tropical agroforestry landscapes.

    PubMed

    Maas, Bea; Clough, Yann; Tscharntke, Teja

    2013-12-01

    Human welfare is significantly linked to ecosystem services such as the suppression of pest insects by birds and bats. However, effects of biocontrol services on tropical cash crop yield are still largely unknown. For the first time, we manipulated the access of birds and bats in an exclosure experiment (day, night and full exclosures compared to open controls in Indonesian cacao agroforestry) and quantified the arthropod communities, the fruit development and the final yield over a long time period (15 months). We found that bat and bird exclusion increased insect herbivore abundance, despite the concurrent release of mesopredators such as ants and spiders, and negatively affected fruit development, with final crop yield decreasing by 31% across local (shade cover) and landscape (distance to primary forest) gradients. Our results highlight the tremendous economic impact of common insectivorous birds and bats, which need to become an essential part of sustainable landscape management. PMID:24131776

  14. Modelling the hydrological behaviour of a coffee agroforestry basin in Costa Rica

    NASA Astrophysics Data System (ADS)

    Gómez-Delgado, F.; Roupsard, O.; Moussa, R.; Le Maire, G.; Taugourdeau, S.; Bonnefond, J. M.; Pérez, A.; van Oijen, M.; Vaast, P.; Rapidel, B.; Voltz, M.; Imbach, P.; Harmand, J. M.

    2010-05-01

    streamflow was constituted by 63% of baseflow originating from the aquifer, 29% of subsurface non-saturated runoff and 8% of surface runoff. Given the low surface runoff observed under the current physical conditions (andisol) and management practices (no tillage, planted trees, bare soil kept by weeding), this agroforestry system on a volcanic soil demonstrated potential to provide valuable HES, such as a reduced superficial displacement-capacity for fertilizers, pesticides and sediments, as well as a streamflow regulation function provided by the highly efficient mechanisms of aquifer recharge and discharge. The proposed combination of experimentation and modelling across ecophysiological and hydrological approaches proved to be useful to account for the behaviour of a given basin, so that it can be applied to compare HES provision for different regions or management alternatives.

  15. Reforestation as a novel abatement and compliance measure for ground-level ozone.

    PubMed

    Kroeger, Timm; Escobedo, Francisco J; Hernandez, José L; Varela, Sebastián; Delphin, Sonia; Fisher, Jonathan R B; Waldron, Janice

    2014-10-01

    High ambient ozone (O3) concentrations are a widespread and persistent problem globally. Although studies have documented the role of forests in removing O3 and one of its precursors, nitrogen dioxide (NO2), the cost effectiveness of using peri-urban reforestation for O3 abatement purposes has not been examined. We develop a methodology that uses available air quality and meteorological data and simplified forest structure growth-mortality and dry deposition models to assess the performance of reforestation for O3 precursor abatement. We apply this methodology to identify the cost-effective design for a hypothetical 405-ha, peri-urban reforestation project in the Houston-Galveston-Brazoria O3 nonattainment area in Texas. The project would remove an estimated 310 tons of (t) O3 and 58 t NO2 total over 30 y. Given its location in a nitrogen oxide (NOx)-limited area, and using the range of Houston area O3 production efficiencies to convert forest O3 removal to its NOx equivalent, this is equivalent to 127-209 t of the regulated NOx. The cost of reforestation per ton of NOx abated compares favorably to that of additional conventional controls if no land costs are incurred, especially if carbon offsets are generated. Purchasing agricultural lands for reforestation removes this cost advantage, but this problem could be overcome through cost-share opportunities that exist due to the public and conservation benefits of reforestation. Our findings suggest that peri-urban reforestation should be considered in O3 control efforts in Houston, other US nonattainment areas, and areas with O3 pollution problems in other countries, wherever O3 formation is predominantly NOx limited. PMID:25201970

  16. Reforestation as a novel abatement and compliance measure for ground-level ozone

    PubMed Central

    Kroeger, Timm; Escobedo, Francisco J.; Hernandez, José L.; Varela, Sebastián; Delphin, Sonia; Fisher, Jonathan R. B.; Waldron, Janice

    2014-01-01

    High ambient ozone (O3) concentrations are a widespread and persistent problem globally. Although studies have documented the role of forests in removing O3 and one of its precursors, nitrogen dioxide (NO2), the cost effectiveness of using peri-urban reforestation for O3 abatement purposes has not been examined. We develop a methodology that uses available air quality and meteorological data and simplified forest structure growth-mortality and dry deposition models to assess the performance of reforestation for O3 precursor abatement. We apply this methodology to identify the cost-effective design for a hypothetical 405-ha, peri-urban reforestation project in the Houston–Galveston–Brazoria O3 nonattainment area in Texas. The project would remove an estimated 310 tons of (t) O3 and 58 t NO2 total over 30 y. Given its location in a nitrogen oxide (NOx)-limited area, and using the range of Houston area O3 production efficiencies to convert forest O3 removal to its NOx equivalent, this is equivalent to 127–209 t of the regulated NOx. The cost of reforestation per ton of NOx abated compares favorably to that of additional conventional controls if no land costs are incurred, especially if carbon offsets are generated. Purchasing agricultural lands for reforestation removes this cost advantage, but this problem could be overcome through cost-share opportunities that exist due to the public and conservation benefits of reforestation. Our findings suggest that peri-urban reforestation should be considered in O3 control efforts in Houston, other US nonattainment areas, and areas with O3 pollution problems in other countries, wherever O3 formation is predominantly NOx limited. PMID:25201970

  17. Brush-eating device promises reforestation, wood energy aid

    SciTech Connect

    Blackman, T.

    1981-01-01

    An invention which began as a low-ground-pressure skidder developed into a machine which clears brush, thins plantations, and can harvest wood for energy. First came the notion of an extra-low-ground-pressure log skidder. A swinging chopper was added to the front to clear the skid roads. Working in manzanita brush 10 to 12 foot tall, and with stems up to 18 inches in diameter, the Shar 20 can clear one to two and a half acres an hour. The 30 will be able to clear two to five acres an hour. The big machine will have two chopper heads rotating in opposite directions to force the chopped wood into a chipper built into the machine. Chips will be blown to a van following the harvester so they can be used for hog fuel or as feedstock for methanol production. The head spins at a relatively slow 450 rpm - a safety factor. Surrounding brush catches most of the cut material, but an occasional chunk of wood does fly several yards. Companies are paying more attention to reforestation. Clearing the land will leave a mulch-like debris on the ground. This offers some shade and helps retain soil moisture. Even when brush is harvested for energy, about 10% of the material is left on the ground. California's Department of Forestry wants to start a five-year clearing cycle for the chaparral stands, ''mowing'' a million acres a year and returning every fifth year to reclear the brush. California alone has 27 million acres of brushland not suitable for timber. A brushy acre averages from 30 to 200 tons of wood at 10% moisture content. The machines are designed to run at up to 12 mph when moving.

  18. Feasibility Study of Carbon Sequestration Through Reforestation in the Chesapeake Bay Watershed of Virginia

    SciTech Connect

    Andy Lacatell; David Shoch; Bill Stanley; Zoe Kant

    2007-03-01

    The Chesapeake Rivers conservation area encompasses approximately 2,000 square miles of agricultural and forest lands in four Virginia watersheds that drain to the Chesapeake Bay. Consulting a time series of classified Landsat imagery for the Chesapeake Rivers conservation area, the project team developed a GIS-based protocol for identifying agricultural lands that could be reforested, specifically agricultural lands that had been without forest since 1990. Subsequent filters were applied to the initial candidate reforestation sites, including individual sites > 100 acres and sites falling within TNC priority conservation areas. The same data were also used to produce an analysis of baseline changes in forest cover within the study period. The Nature Conservancy and the Virginia Department of Forestry identified three reforestation/management models: (1) hardwood planting to establish old-growth forest, (2) loblolly pine planting to establish working forest buffer with hardwood planting to establish an old-growth core, and (3) loblolly pine planting to establish a working forest. To assess the relative carbon sequestration potential of these different strategies, an accounting of carbon and total project costs was completed for each model. Reforestation/management models produced from 151 to 171 tons carbon dioxide equivalent per acre over 100 years, with present value costs of from $2.61 to $13.28 per ton carbon dioxide equivalent. The outcome of the financial analysis was especially sensitive to the land acquisition/conservation easement cost, which represented the most significant, and also most highly variable, single cost involved. The reforestation/management models explored all require a substantial upfront investment prior to the generation of carbon benefits. Specifically, high land values represent a significant barrier to reforestation projects in the study area, and it is precisely these economic constraints that demonstrate the economic additionality

  19. Contribution of deforestation to atmospheric CO/sub 2/ and reforestation as an option to control CO/sub 2/

    SciTech Connect

    Kinsman, J.D.; Marland, G.

    1989-01-01

    In this paper we discuss various aspects of global climate change as related to forests: the rate of deforestation; CO/sub 2/ emissions resulting from deforestation; and reforestation as a means to control atmospheric CO/sub 2/. We also include for perspective a discussion of current policy considerations related to methods for reducing deforestation or promoting reforestation. 68 refs.

  20. Changes in soil organic carbon and total nitrogen in croplands converted to walnut-based agroforestry systems and orchards in southeastern Loess Plateau of China.

    PubMed

    Lu, Sen; Meng, Ping; Zhang, Jinsong; Yin, Changjun; Sun, Shiyou

    2015-11-01

    Limited information is available on the effects of agroforestry system practices on soil properties in the Loess Plateau of China. Over the last decade, a vegetation restoration project has been conducted in this area by converting cropland into tree-based agroforestry systems and orchards to combat soil erosion and degradation. The objective of the present study was to determine the effects of land use conversion on soil organic carbon and total nitrogen in southeastern Loess Plateau. The experiment included three treatments: walnut intercropping system (AF), walnut orchard (WO), and traditional cropland (CR). After 7 years of continual management, soil samples were collected at 0-10, 10-30, and 30-50-cm depths for three treatments, and soil organic carbon (SOC) and total nitrogen (TN) were measured. Results showed that compared with the CR and AF treatments, WO treatment decreased both SOC and TN concentrations in the 0-50-cm soil profile. However, similar patterns of SOC and TN concentrations were observed in the AF and CR treatments across the entire profile. The SOC stocks at 0-50-cm depth were 5.42, 5.52, and 4.67 kg m(-2) for CR, AF, and WO treatments, respectively. The calculated TN stocks at 0-50-cm depth were 0.63, 0.62, and 0.57 kg m(-2) for CR, AF, and WO treatments, respectively. This result demonstrated that the stocks of SOC and TN in WO were clearly lower than those of AF and CR and that the walnut-based agroforestry system was more beneficial than walnut monoculture in terms of SOC and TN sequestration. Owing to the short-term intercropping practice, the changes in SOC and TN stocks were slight in AF compared with those in CR. However, a significant decrease in SOC and TN stocks was observed during the conversion of cropland to walnut orchard after 7 years of management. We also found that land use types had no significant effect on soil C/N ratio. These findings demonstrated that intercropping between walnut rows can potentially maintain

  1. Floristic evolution in an agroforestry system cultivation in Southern Brazil.

    PubMed

    Silva, Luís C R; Machado, Sebastião A; Galvão, Franklin; Figueiredo, Afonso

    2016-06-01

    Bracatinga (Mimosa scabrella Bentham) is an important pioneer tree species in Ombrophylous Mixed Forest of Brazil and is widely used as an energy source. In traditional agroforestry systems, regeneration is induced by fire, then pure and dense stands known as bracatinga stands (bracatingais) are formed. In the first year, annual crops are intercalated with the seedlings. At that time the seedlings are thinned, then the stands remain at a fallow period and cut at seven years old. The species is very important mainly for small landowners. We studied the understory species that occur naturally during the succession over several years in order to manage them rationally in the future and maintain the natural vegetation over time. Three to 20 year-old Bracatinga stands were sampled between 1998 and 2011. All tree species with diameter at breast height (DBH) ≥ 5 cm were measured.The floristic evolution was assessed with respect to Sociability Index, the Shannon Diversity Index and the Pielou Evenness Index. Graphs of rank/abundance over different age groups were evaluated using the Kolmogorov-Smirnov test. We identified 153 species dispersed throughout the understory and tend to become aggregated over time. PMID:27276374

  2. Enhanced selective metal adsorption on optimised agroforestry waste mixtures.

    PubMed

    Rosales, Emilio; Ferreira, Laura; Sanromán, M Ángeles; Tavares, Teresa; Pazos, Marta

    2015-04-01

    The aim of this work is to ascertain the potentials of different agroforestry wastes to be used as biosorbents in the removal of a mixture of heavy metals. Fern (FE), rice husk (RI) and oak leaves (OA) presented the best removal percentages for Cu(II) and Ni(II), Mn(II) and Zn(II) and Cr(VI), respectively. The performance of a mixture of these three biosorbents was evaluated, and an improvement of 10% in the overall removal was obtained (19.25mg/g). The optimum mixture proportions were determined using simplex-centroid mixture design method (FE:OA:RI=50:13.7:36.3). The adsorption kinetics and isotherms of the optimised mixture were fit by the pseudo-first order kinetic model and Langmuir isotherm. The adsorption mechanism was studied, and the effects of the carboxylic, hydroxyl and phenolic groups on metal-biomass binding were demonstrated. Finally, the recoveries of the metals using biomass were investigated, and cationic metal recoveries of 100% were achieved when acidic solutions were used. PMID:25681794

  3. Technical and institutional innovation in agroforestry for protected areas management in the Brazilian Amazon: opportunities and limitations.

    PubMed

    Schroth, Götz; da Mota, Maria do Socorro S

    2013-08-01

    Tropical forest countries are struggling with the partially conflicting policy objectives of socioeconomic development, forest conservation, and safeguarding the livelihoods of local forest-dependent people. We worked with communities in the lower Tapajós region of the central Brazilian Amazon for over 10 years to understand their traditional and present land use practices, the constraints, and decision making processes imposed by their biophysical, socioeconomic, and political environment, and to facilitate development trajectories to improve the livelihoods of forest communities while conserving the forest on the farms and in the larger landscape. The work focused on riverine communities initially in the Tapajós National Forest and then in the Tapajós-Arapiuns Extractive Reserve. These communities have a century-old tradition of planting rubber agroforests which despite their abandonment during the 1990s still widely characterize the vegetation of the river banks, especially in the two protected areas where they are safe from the recent expansion of mechanized rice and soybean agriculture. The project evolved from the capacity-building of communities in techniques to increase the productivity of the rubber agroforests without breaking their low-input and low-risk logic, to the establishment of a community enterprise that allowed reserve inhabitants to reforest their own land with tree species of their choice and sell reforestation (not carbon) credits to local timber companies while retaining the ownership of the trees. By making land use practices economically more viable and ecologically more appropriate for protected areas, the project shows ways to strengthen the system of extractive and sustainable development reserves that protects millions of hectares of Amazon forest with the consent of the communities that inhabit them. PMID:23636205

  4. Technical and Institutional Innovation in Agroforestry for Protected Areas Management in the Brazilian Amazon: Opportunities and Limitations

    NASA Astrophysics Data System (ADS)

    Schroth, Götz; da Mota, Maria do Socorro S.

    2013-08-01

    Tropical forest countries are struggling with the partially conflicting policy objectives of socioeconomic development, forest conservation, and safeguarding the livelihoods of local forest-dependent people. We worked with communities in the lower Tapajós region of the central Brazilian Amazon for over 10 years to understand their traditional and present land use practices, the constraints, and decision making processes imposed by their biophysical, socioeconomic, and political environment, and to facilitate development trajectories to improve the livelihoods of forest communities while conserving the forest on the farms and in the larger landscape. The work focused on riverine communities initially in the Tapajós National Forest and then in the Tapajós-Arapiuns Extractive Reserve. These communities have a century-old tradition of planting rubber agroforests which despite their abandonment during the 1990s still widely characterize the vegetation of the river banks, especially in the two protected areas where they are safe from the recent expansion of mechanized rice and soybean agriculture. The project evolved from the capacity-building of communities in techniques to increase the productivity of the rubber agroforests without breaking their low-input and low-risk logic, to the establishment of a community enterprise that allowed reserve inhabitants to reforest their own land with tree species of their choice and sell reforestation (not carbon) credits to local timber companies while retaining the ownership of the trees. By making land use practices economically more viable and ecologically more appropriate for protected areas, the project shows ways to strengthen the system of extractive and sustainable development reserves that protects millions of hectares of Amazon forest with the consent of the communities that inhabit them.

  5. Reforestation in Arid Lands. Appropriate Technologies for Development. Manual M-5.

    ERIC Educational Resources Information Center

    Palmer, Virginia C., Ed.

    This manual presents some current, state-of-the-art examples of forestry programs in West Africa. It is based on the collective experiences of foresters and of local farmers and herders. Since many of the problems of reforestation of dry areas are the same worldwide, the text (which focuses on the broad subject of project implementation) includes…

  6. Soil cover by natural trees in agroforestry systems

    NASA Astrophysics Data System (ADS)

    Diaz-Ambrona, C. G. H.; Almoguera Millán, C.; Tarquis Alfonso, A.

    2009-04-01

    The dehesa is common agroforestry system in the Iberian Peninsula. These open oak parklands with silvo-pastoral use cover about two million hectares. Traditionally annual pastures have been grazed by cows, sheep and also goats while acorns feed Iberian pig diet. Evergreen oak (Quercus ilex L.) has other uses as fuelwood collection and folder after tree pruning. The hypothesis of this work is that tree density and canopy depend on soil types. We using the spanish GIS called SIGPAC to download the images of dehesa in areas with different soil types. True colour images were restoring to a binary code, previously canopy colour range was selected. Soil cover by tree canopy was calculated and number of trees. Processing result was comparable to real data. With these data we have applied a dynamic simulation model Dehesa to determine evergreen oak acorn and annual pasture production. The model Dehesa is divided into five submodels: Climate, Soil, Evergreen oak, Pasture and Grazing. The first three require the inputs: (i) daily weather data (maximum and minimum temperatures, precipitation and solar radiation); (ii) the soil input parameters for three horizons (thickness, field capacity, permanent wilting point, and bulk density); and (iii) the tree characterization of the dehesa (tree density, canopy diameter and height, and diameter of the trunk). The influence of tree on pasture potential production is inversely proportional to the canopy cover. Acorn production increase with tree canopy cover until stabilizing itself, and will decrease if density becomes too high (more than 80% soil tree cover) at that point there is competition between the trees. Main driving force for dehesa productivity is soil type for pasture, and tree cover for acorn production. Highest pasture productivity was obtained on soil Dystric Planosol (Alfisol), Dystric Cambisol and Chromo-calcic-luvisol, these soils only cover 22.4% of southwest of the Iberian peninssula. Lowest productivity was

  7. Bottomland hardwood establishment and avian colonization of reforested sites in the Mississippi Alluvial Valley

    USGS Publications Warehouse

    Wilson, R.R.; Twedt, D.J.

    2005-01-01

    Reforestation of bottomland hardwood sites in the Mississippi Alluvial Valley has markedly increased in recent years, primarily due to financial incentive programs such as the Wetland Reserve Program, Partners for Wildlife Program, and state and private conservation programs. An avian conservation plan for the Mississippi Alluvial Valley proposes returning a substantial area of cropland to forested wetlands. Understanding how birds colonize reforested sites is important to assess the effectiveness of avian conservation. We evaluated establishment of woody species and assessed bird colonization on 89 reforested sites. These reforested sites were primarily planted with heavy-seeded oaks (Quercus spp.) and pecans (Carya illinoensis). Natural invasion of light-seeded species was expected to diversify these forests for wildlife and sustainable timber harvest. Planted tree species averaged 397 + 36 stems/ha-1, whereas naturally invading trees averaged 1675 + 241 stems/ha. However, naturally invading trees were shorter than planted trees and most natural invasion occurred <100 m from an existing forested edge. Even so, planted trees were relatively slow to develop vertical structure, especially when compared with tree species planted and managed for pulpwood production. Slow development of vertical structure resulted in grassland bird species, particularly dickcissel (Spiza americana) and red-winged blackbird (Agelaius phoeniceus), being the dominant avian colonizers for the first 7 years post-planting. High priority bird species (as defined by Partners in Flight), such as prothonotary warbler (Protonotaria citrea) and wood thrush (Hylocichla mustelina), were not frequently detected until stands were 15 years old. Canonical correspondence analysis revealed tree height had the greatest influence on the bird communities colonizing reforested sites. Because colonization by forest birds is dependent on tree height, we recommend inclusion of at least one fast-growing tree

  8. Increasing the effectiveness of native forest regeneration and reforestation: towards climate-change adaptation in drylands

    NASA Astrophysics Data System (ADS)

    Branquinho, Cristina; Príncipe, Adriana; Nunes, Alice; Kobel, Melanie; Soares, Cristina; Pinho, Pedro

    2016-04-01

    The recent expansion of the semiarid climate to all the region of the south of Portugal and the growing impact of climate change demands local adaptation. The growth of the native forest represents a strategy at the ecosystem level to adapt to climate change since it increases resilience and increases also de delivery of ecosystem services such as the increment of organic matter in the soil, carbon and nitrogen, biodiversity, water infiltration, etc. Moreover decreases susceptibility to desertification. For that reason, large areas have been reforested in the south of Portugal with the native species holm oak and cork oak but with a low rate of effectiveness. Our goal in this work is to show how the cost-benefit relation of the actions intended to expand the forest of the Portuguese semiarid can be lowered by taking into account the microclimatic conditions and high spatial resolution management. The potential of forest regeneration was modelled at the local and regional level in the semiarid area using information concerning the Potential Solar Radiation. This model gives us the rate of native forest regeneration after a disturbance with high spatial resolution. Based on this model the territory was classified in: i) easy regeneration areas; ii) areas with the need of assisted reforestation, using methods that increase water and soil conservation; iii) areas of difficult reforestation because of the costs. Additionally a summary of the success of reforestations was made in the historical semiarid since the 60s based on the evaluation of a series of case studies, where we quantified the ecosystem services currently delivered by the reforested ecosystems. Acknowledgement: Programa Adapt: financed by EEA Grants and Fundo Português de Carbono

  9. Status of microbial diversity in agroforestry systems in Tamil Nadu, India.

    PubMed

    Radhakrishnan, Srinivasan; Varadharajan, Mohan

    2016-06-01

    Soil is a complex and dynamic biological system. Agroforestry systems are considered to be an alternative land use option to help and prevent soil degradation, improve soil fertility, microbial diversity, and organic matter status. An increasing interest has emerged with respect to the importance of microbial diversity in soil habitats. The present study deals with the status of microbial diversity in agroforestry systems in Tamil Nadu. Eight soil samples were collected from different fields in agroforestry systems in Cuddalore, Villupuram, Tiruvanamalai, and Erode districts, Tamil Nadu. The number of microorganisms and physico-chemical parameters of soils were quantified. Among different microbial population, the bacterial population was recorded maximum (64%), followed by actinomycetes (23%) and fungi (13%) in different samples screened. It is interesting to note that the microbial population was positively correlated with the physico-chemical properties of different soil samples screened. Total bacterial count had positive correlation with soil organic carbon (C), moisture content, pH, nitrogen (N), and micronutrients such as Iron (Fe), copper (Cu), and zinc (Zn). Similarly, the total actinomycete count also showed positive correlations with bulk density, moisture content, pH, C, N, phosphorus (P), potassium (K), calcium (Ca), copper (Cu), magnesium (Mg), manganese (Mn), and zinc (Zn). It was also noticed that the soil organic matter, vegetation, and soil nutrients altered the microbial community under agroforestry systems. PMID:26924716

  10. KURA CLOVER INTERCROPPED IN A PECAN AGROFORESTRY SYSTEM IMPROVES SOIL QUALITY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Intercropping the alleys of agroforestry systems is desirable to provide income from the field until the tree crop begins to yield. However, cultivation of annual crops in the alleys may decrease soil organic matter and increase soil erosion, especially on sloping landscapes. Perennial crops maintai...

  11. Cover crops alter phosphorus soil fractions and organic matter accumulation in a Peruvian cacao agroforestry system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In many tropical soils, excessive weathering of primary minerals confounded by intense agricultural production has resulted in the depletion of organic matter and plant available forms of phosphorus (P). Long-term growth of cover crops in tropical agroforestry systems have been shown to influence nu...

  12. Agroforestry leads to shifts within the gammaproteobacterial microbiome of banana plants cultivated in Central America

    PubMed Central

    Köberl, Martina; Dita, Miguel; Martinuz, Alfonso; Staver, Charles; Berg, Gabriele

    2015-01-01

    Bananas (Musa spp.) belong to the most important global food commodities, and their cultivation represents the world's largest monoculture. Although the plant-associated microbiome has substantial influence on plant growth and health, there is a lack of knowledge of the banana microbiome and its influencing factors. We studied the impact of (i) biogeography, and (ii) agroforestry on the banana-associated gammaproteobacterial microbiome analyzing plants grown in smallholder farms in Nicaragua and Costa Rica. Profiles of 16S rRNA genes revealed high abundances of Pseudomonadales, Enterobacteriales, Xanthomonadales, and Legionellales. An extraordinary high diversity of the gammaproteobacterial microbiota was observed within the endophytic microenvironments (endorhiza and pseudostem), which was similar in both countries. Enterobacteria were identified as dominant group of above-ground plant parts (pseudostem and leaves). Neither biogeography nor agroforestry showed a statistically significant impact on the gammaproteobacterial banana microbiome in general. However, indicator species for each microenvironment and country, as well as for plants grown in Coffea intercropping systems with and without agri-silvicultural production of different Fabaceae trees (Inga spp. in Nicaragua and Erythrina poeppigiana in Costa Rica) could be identified. For example, banana plants grown in agroforestry systems were characterized by an increase of potential plant-beneficial bacteria, like Pseudomonas and Stenotrophomonas, and on the other side by a decrease of Erwinia. Hence, this study could show that as a result of legume-based agroforestry the indigenous banana-associated gammaproteobacterial community noticeably shifted. PMID:25717322

  13. Soil and litter fauna of cacao agroforestry systems in Bahia, Brazil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agroforestry systems deposit great amounts of plant residues on soil; and eventually, this leads to high levels of soil organic matter content and has increased soil biodiversity and improved its conservation. This study compares the distribution of meso and macrofaunal communities in soil and litte...

  14. Intercropping with Kura Clover Improves Soil Quality in a Pecan Agroforestry System

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Intercropping the alleys of agroforestry systems provides income until the tree crop begins to yield. However, cultivation of annual crops or intensive herbicidal control of vegetation in the alleys decreases soil organic matter and increases soil erosion, especially on sloping landscapes. Perennial...

  15. Barriers and Coping Mechanisms Relating to Agroforestry Adoption by Smallholder Farmers in Zimbabwe

    ERIC Educational Resources Information Center

    Chitakira, Munyaradzi; Torquebiau, Emmanuel

    2010-01-01

    Purpose: The purpose of the present study was to investigate agroforestry adoption by smallholder farmers in Gutu District, Zimbabwe. Design/Methodology/Approach: The methodology was based on field data collected through household questionnaires, key informant interviews and direct observations. Findings: Major findings reveal that traditional…

  16. Carbon storage in soil-size fractions under two cacao agroforestry systems in Bahia, Brazil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Shaded-perennial agroforestry systems contain relatively higher quantities of soil carbon (C) because of continuous deposition of plant residues; however, the amount of C sequestered in the soil will vary depending on the turnover time and the extent of physical protection of different soil organic ...

  17. Distribution of oxidizable organic c fractions in soils under cacao agroforestry systems in Southern Bahia, Brazil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agroforestry systems can play a major role in the sequestration of carbon (C) because of their higher input of organic materials to the soil. The importance of organic carbon to the physical, chemical, and biological aspects of soil quality is well recognized. However, total organic carbon measureme...

  18. Soil Quality in a Pecan Agroforestry System is Improved with Intercropped Kura Clover

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Intercropping alleys of agroforestry systems provides an income source until the tree crop produces harvestable yields. However, cultivation of annual crops decreases soil organic matter and increases soil erosion, especially on sloping landscapes. Perennial crops maintain a continuous soil cover, m...

  19. Agroforestry leads to shifts within the gammaproteobacterial microbiome of banana plants cultivated in Central America.

    PubMed

    Köberl, Martina; Dita, Miguel; Martinuz, Alfonso; Staver, Charles; Berg, Gabriele

    2015-01-01

    Bananas (Musa spp.) belong to the most important global food commodities, and their cultivation represents the world's largest monoculture. Although the plant-associated microbiome has substantial influence on plant growth and health, there is a lack of knowledge of the banana microbiome and its influencing factors. We studied the impact of (i) biogeography, and (ii) agroforestry on the banana-associated gammaproteobacterial microbiome analyzing plants grown in smallholder farms in Nicaragua and Costa Rica. Profiles of 16S rRNA genes revealed high abundances of Pseudomonadales, Enterobacteriales, Xanthomonadales, and Legionellales. An extraordinary high diversity of the gammaproteobacterial microbiota was observed within the endophytic microenvironments (endorhiza and pseudostem), which was similar in both countries. Enterobacteria were identified as dominant group of above-ground plant parts (pseudostem and leaves). Neither biogeography nor agroforestry showed a statistically significant impact on the gammaproteobacterial banana microbiome in general. However, indicator species for each microenvironment and country, as well as for plants grown in Coffea intercropping systems with and without agri-silvicultural production of different Fabaceae trees (Inga spp. in Nicaragua and Erythrina poeppigiana in Costa Rica) could be identified. For example, banana plants grown in agroforestry systems were characterized by an increase of potential plant-beneficial bacteria, like Pseudomonas and Stenotrophomonas, and on the other side by a decrease of Erwinia. Hence, this study could show that as a result of legume-based agroforestry the indigenous banana-associated gammaproteobacterial community noticeably shifted. PMID:25717322

  20. Resolving Controlled Vocabulary in DITA Markup: A Case Example in Agroforestry

    ERIC Educational Resources Information Center

    Zschocke, Thomas

    2012-01-01

    Purpose: This paper aims to address the issue of matching controlled vocabulary on agroforestry from knowledge organization systems (KOS) and incorporating these terms in DITA markup. The paper has been selected for an extended version from MTSR'11. Design/methodology/approach: After a general description of the steps taken to harmonize controlled…

  1. A common framework for GHG assessment protocols in temperate agroforestry systems: connecting via GRACEnet

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There are technical and financial advantages for pursuing agroforestry-derived mitigation and adaptation services simultaneously, with a recognition that carbon (C) payments could assist in supporting the deployment of adaptation strategies (Motocha et al. (2012). However, we lack the repeated/repea...

  2. Distribution of organic C oxidizable fractions in soils under cacao agroforestry systems in southern Bahia, Brazil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agroforestry systems can play a major role in the sequestration of carbon (C) because of their higher input of organic material to the soil. The importance of organic carbon to the physical, chemical, and biological aspects of soil quality is well recognized. However, total organic carbon measuremen...

  3. Soil classification and carbon storage in cacao agroforestry farming systems of Bahia, Brazil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Information concerning the classification of soils and their properties under cacao agroforestry systems of the Atlantic rain forest biome region in the Southeast of Bahia Brazil is largely unknown. Soil and climatic conditions in this region are favorable for high soil carbon storage. This study is...

  4. Changing human-ecological relationships and drivers using the Quesungual agroforestry system in western Honduras

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The development of sustainable agricultural production systems in the tropics is challenging in part because the local and external conditions that affect sustainability are constantly in flux. The Quesungual Agroforestry System (QSMAS) was developed in response to these changing conditions. The his...

  5. Field Note: Standard Web Application for Information Exchange on Agroforestry in India

    ERIC Educational Resources Information Center

    Ajit; Nighat Jabeen; Handa, A. K.; Uma

    2008-01-01

    Agroforestry (AF)/forestry is no longer an isolated field, with so many developmental activities having links with this sector, and thus the information required to be handled by the researchers all over the world has increased exponentially. This article discusses a website that was developed by the National Research Centre for Agroforestry…

  6. Modelling the hydrological behaviour of a coffee agroforestry basin in Costa Rica

    NASA Astrophysics Data System (ADS)

    Gómez-Delgado, F.; Roupsard, O.; Le Maire, G.; Taugourdeau, S.; Pérez, A.; van Oijen, M.; Vaast, P.; Rapidel, B.; Harmand, J. M.; Voltz, M.; Bonnefond, J. M.; Imbach, P.; Moussa, R.

    2011-01-01

    percolation, measurement errors and/or inter-annual changes in soil and aquifer water stocks. The model indicated an interception loss equal to 4% of R, a surface runoff of 4% and an infiltration component of 92%. The modelled streamflow was constituted by 87% of baseflow originating from the aquifer, 7% of subsurface non-saturated runoff and 6% of surface runoff. Given the low surface runoff observed under the current physical conditions (andisol) and management practices (no tillage, planted trees, bare soil kept by weeding), this agroforestry system on a volcanic soil demonstrated potential to provide valuable HES, such as a reduced superficial displacement-capacity for fertilizers, pesticides and sediments, as well as a streamflow regulation function provided by the highly efficient mechanisms of aquifer recharge and discharge. The proposed combination of experimentation and modelling across ecophysiological and hydrological approaches proved to be useful to account for the behaviour of a given basin, so that it can be applied to compare HES provision for different regions or management alternatives.

  7. Community diversity, structure and carbon footprint of nematode food web following reforestation on degraded Karst soil.

    PubMed

    Hu, Ning; Li, Hui; Tang, Zheng; Li, Zhongfang; Tian, Jing; Lou, Yilai; Li, Jianwei; Li, Guichun; Hu, Xiaomin

    2016-01-01

    We examined community diversity, structure and carbon footprint of nematode food web along a chronosequence of T. Sinensis reforestation on degraded Karst. In general, after the reforestation: a serious of diversity parameters and community indices (Shannon-Weinier index (H'), structure index (SI), etc.) were elevated; biomass ratio of fungivores to bacterivores (FFC/BFC), and fungi to bacteria (F/B) were increased, and nematode channel ratio (NCR) were decreased; carbon footprints of all nematode trophic groups, and biomass of bacteria and fungi were increased. Our results indicate that the Karst aboveground vegetation restoration was accompanied with belowground nematode food web development: increasing community complexity, function and fungal dominance in decomposition pathway, and the driving forces included the bottom-up effect (resource control), connectedness of functional groups, as well as soil environments. PMID:27311984

  8. Community diversity, structure and carbon footprint of nematode food web following reforestation on degraded Karst soil

    NASA Astrophysics Data System (ADS)

    Hu, Ning; Li, Hui; Tang, Zheng; Li, Zhongfang; Tian, Jing; Lou, Yilai; Li, Jianwei; Li, Guichun; Hu, Xiaomin

    2016-06-01

    We examined community diversity, structure and carbon footprint of nematode food web along a chronosequence of T. Sinensis reforestation on degraded Karst. In general, after the reforestation: a serious of diversity parameters and community indices (Shannon-Weinier index (H‧), structure index (SI), etc.) were elevated; biomass ratio of fungivores to bacterivores (FFC/BFC), and fungi to bacteria (F/B) were increased, and nematode channel ratio (NCR) were decreased; carbon footprints of all nematode trophic groups, and biomass of bacteria and fungi were increased. Our results indicate that the Karst aboveground vegetation restoration was accompanied with belowground nematode food web development: increasing community complexity, function and fungal dominance in decomposition pathway, and the driving forces included the bottom-up effect (resource control), connectedness of functional groups, as well as soil environments.

  9. Community diversity, structure and carbon footprint of nematode food web following reforestation on degraded Karst soil

    PubMed Central

    Hu, Ning; Li, Hui; Tang, Zheng; Li, Zhongfang; Tian, Jing; Lou, Yilai; Li, Jianwei; Li, Guichun; Hu, Xiaomin

    2016-01-01

    We examined community diversity, structure and carbon footprint of nematode food web along a chronosequence of T. Sinensis reforestation on degraded Karst. In general, after the reforestation: a serious of diversity parameters and community indices (Shannon-Weinier index (H′), structure index (SI), etc.) were elevated; biomass ratio of fungivores to bacterivores (FFC/BFC), and fungi to bacteria (F/B) were increased, and nematode channel ratio (NCR) were decreased; carbon footprints of all nematode trophic groups, and biomass of bacteria and fungi were increased. Our results indicate that the Karst aboveground vegetation restoration was accompanied with belowground nematode food web development: increasing community complexity, function and fungal dominance in decomposition pathway, and the driving forces included the bottom-up effect (resource control), connectedness of functional groups, as well as soil environments. PMID:27311984

  10. Bats (Mammalia: Chiroptera) in native and reforested areas in Rancho Alegre, Paraná, Brazil.

    PubMed

    Gallo, Patricia Helena; dos Reis, Nelio Roberto; Andrade, Fabio Rodrigo; de Almeida, Inaê Guion

    2010-12-01

    Abstract: Generally, natural environments have been transformed into small forest remnants, with the consequent habitat loss and species extinction. The North Paraná State is not an exception, since only 2 to 4% of the original ecosystem occurs in small fragments of Stational Semidecidual Forest. We studied the species richness and abundance of bats in two forest fragments from the Fazenda Congonhas, in Rancho Alegre city, Parana State, Brazil. Four samplings were undertaken in a legally protected native area (107.8 ha) and in a reforested area (11.8 ha) between April 2007 and March 2008. Samplings began at nightfall and lasted six hours,during two consecutive nights in each location. The individuals were captured using eight mist nets, with the same capture effort in both environments. A total of 397 individuals, 14 species and 10 genera were captured in the native area; while in the reforested area, 105 individuals, six species and four genera. Artibeus lituratus was the most common species in both fragments (n = 328, 65.3%), followed by Artibeus fimbriatus (n = 44, 8.8%) and Artibeus jamaicensis (n = 30, 6.0%). Other species including Platyrrhinus lineatus, Carollia perspicillata, Sturnira lilium, Chrotopterus aurintus, Desmodus rotundus, Michronycteris megalotis, Phyllostomus hastatus, Phyllostomus discolor, Myoti levis, Myotis nigricans and Lasiurus blossevillii, accounted for 19.9% of the captures. The native area presented higher values of species richness (S = 14) and diversity (H' = 1.4802) in comparison to the reforested area (S = 6, H '= 0.57015). The t-test evidenced a significant difference between diversity among the sites (t = 7.1075). Chao 1 index indicated that the sampling effort recorded approximately 78% from the total species richness for the native area and 75% for the reforested area. Therefore, the preservation of the forest fragment is essential since it provides habitat for a diverse community of bats. Forest management and reforestation

  11. Effect of shade on Arabica coffee berry disease development: Toward an agroforestry system to reduce disease impact.

    PubMed

    Mouen Bedimo, J A; Njiayouom, I; Bieysse, D; Ndoumbè Nkeng, M; Cilas, C; Nottéghem, J L

    2008-12-01

    Coffee berry disease (CBD), caused by Colletotrichum kahawae, is a major constraint for Arabica coffee cultivation in Africa. The disease is specific to green berries and can lead to 60% harvest losses. In Cameroon, mixed cropping systems of coffee with other crops, such as fruit trees, are very widespread agricultural practices. Fruit trees are commonly planted at random on coffee farms, providing a heterogeneous shading pattern for coffee trees growing underneath. Based on a recent study of CBD, it is known that those plants can reduce disease incidence. To assess the specific effect of shade, in situ and in vitro disease development was compared between coffee trees shaded artificially by a net and trees located in full sunlight. In the field, assessments confirmed a reduction in CBD on trees grown under shade compared with those grown in full sunlight. Artificial inoculations in the laboratory showed that shade did not have any effect on the intrinsic susceptibility of coffee berries to CBD. Coffee shading mainly acts on environmental parameters in limiting disease incidence. In addition to reducing yield losses, agroforestry system may also be helpful in reducing chemical control of the disease and in diversifying coffee growers' incomes. PMID:19000007

  12. GHG Mitigation potential and cost in tropical forestry - Relative role for agroforestry

    SciTech Connect

    Makundi, Willy R.; Sathaye, Jayant A.

    2004-01-01

    This paper summarizes studies of carbon mitigation potential (MP) and costs of forestry options in seven developing countries with a focus on the role of agroforestry. A common methodological approach known as comprehensive mitigation assessment process (COMAP) was used in each study to estimate the potential and costs between 2000 and 2030. The approach requires the projection of baseline and mitigation land-use scenarios derived from the demand for forest products and forestland for other uses such as agriculture and pasture. By using data on estimated carbon sequestration, emission avoidance, costs and benefits, the model enables one to estimate cost effectiveness indicators based on monetary benefit per t C, as well as estimates of total mitigation costs and potential when the activities are implemented at equilibrium level. The results show that about half the MP of 6.9 Gt C (an average of 223 Mt C per year) between 2000 and 2030 in the seven countries could be achieved at a negative cost, and the other half at costs not exceeding $100 per t C. Negative cost indicates that non-carbon revenue is sufficient to offset direct costs of about half of the options. The agroforestry options analyzed bear a significant proportion of the potential at medium to low cost per t C when compared to other options. The role of agroforestry in these countries varied between 6% and 21% of the MP, though the options are much more cost effective than most due to the low wage or opportunity cost of rural labor. Agroforestry options are attractive due to the large number of people and potential area currently engaged in agriculture, but they pose unique challenges for carbon and cost accounting due to the dispersed nature of agricultural activities in the tropics, as well as specific difficulties arising from requirements for monitoring, verification, leakage assessment and the establishment of credible baselines.

  13. Mitigation potential and cost in tropical forestry - relative role for agroforestry

    SciTech Connect

    Makundi, Willy R.; Sathaye, Jayant A.

    2004-01-01

    This paper summarizes studies of carbon mitigation potential (MP) and costs of forestry options in seven developing countries with a focus on the role of agroforestry. A common methodological approach known as comprehensive mitigation assessment process (COMAP) was used in each study to estimate the potential and costs between 2000 and 2030. The approach requires the projection of baseline and mitigation land-use scenarios derived from the demand for forest products and forestland for other uses such as agriculture and pasture. By using data on estimated carbon sequestration, emission avoidance, costs and benefits, the model enables one to estimate cost effectiveness indicators based on monetary benefit per t C, as well as estimates of total mitigation costs and potential when the activities are implemented at equilibrium level. The results show that about half the MP of 6.9 Gt C (an average of 223 Mt C per year) between 2000 and 2030 in the seven countries could be achieved at a negative cost, and the other half at costs not exceeding $100 per t C. Negative cost indicates that non-carbon revenue is sufficient to offset direct costs of about half of the options. The agroforestry options analyzed bear a significant proportion of the potential at medium to low cost per t C when compared to other options. The role of agroforestry in these countries varied between 6% and 21% of the MP, though the options are much more cost effective than most due to the low wage or opportunity cost of rural labor. Agroforestry options are attractive due to the large number of people and potential area currently engaged in agriculture, but they pose unique challenges for carbon and cost accounting due to the dispersed nature of agricultural activities in the tropics, as well as specific difficulties arising from requirements for monitoring, verification, leakage assessment and the establishment of credible baselines.

  14. Impact of Reforestation on Local Climate and Environment in a Semi-arid Urban Valley, Northwestern China

    NASA Astrophysics Data System (ADS)

    Xia, D.; Yu, Y.; He, J.

    2015-12-01

    Since 1999 Chinese government has invested more than 800 million Yuan to reforest the southern and the northern mountains surrounding urban Lanzhou - a typical semi-arid city located in a river valley, Northwestern China. Until 2009 obvious land use change occurred, with 69.2% of the reforested area been changed from grasslands, croplands, barren or sparsely vegetated land to closed shrublands and 20.6% been changed from closed shrublands, grasslands, and croplands to forests. This study assesses the impact of these changes on local climate and environment in winter using WRF (Weather Research & Forecasting) model incorporated with high-resolution remotely sensed land cover data for 1999 and 2009 and the FLEXible PARTicle (FLEXPART) dispersion model. Results indicate that the changes in albedo, surface exchange coefficient and surface soil heat conductivity related to the reforestation led to the changes in surface net radiation and the surface energy partitioning, which in turn affected the meteorology fields and enhanced the mountain-valley wind circulation. The amount of air exchanged between the valley and the outside increased after reforestation during the day, with the largest increase of 10 %, while it changed little during the night on winter sunny day with no snow cover. The sensitivity analysis using FLEXPART-WRF model indicates that the reforestation affected the spatial distribution of pollutants and slightly improved the urban air quality in winter. And the greening program of Lanzhou has special reference to other valley urbans.

  15. Below-ground interspecific competition for water in a rubber agroforestry system may enhance water utilization in plants

    PubMed Central

    Wu, Junen; Liu, Wenjie; Chen, Chunfeng

    2016-01-01

    Rubber-based (Hevea brasiliensis) agroforestry systems are regarded as the best way to improve the sustainability of rubber monocultures, but few reports have examined water use in such systems. Accordingly, we tested whether interplanting facilitates water utilization of rubber trees using stable isotope (δD, δ18O, and δ13C) methods and by measuring soil water content (SWC), shoot potential, and leaf C and N concentrations in a Hevea-Flemingia agroforestry system in Xishuangbanna, southwestern China. We detected a big difference in the utilization of different soil layer water between both species in this agroforestry system, as evidenced by the opposite seasonal fluctuations in both δD and δ18O in stem water. However, similar predawn shoot potential of rubber trees at both sites demonstrating that the interplanted species did not affect the water requirements of rubber trees greatly. Rubber trees with higher δ13C and more stable physiological indexes in this agroforestry system showed higher water use efficiency (WUE) and tolerance ability, and the SWC results suggested this agroforestry is conductive to water conservation. Our results clearly indicated that intercropping legume plants with rubber trees can benefit rubber trees own higher N supply, increase their WUE and better utilize soil water of each soil layer. PMID:26781071

  16. Below-ground interspecific competition for water in a rubber agroforestry system may enhance water utilization in plants.

    PubMed

    Wu, Junen; Liu, Wenjie; Chen, Chunfeng

    2016-01-01

    Rubber-based (Hevea brasiliensis) agroforestry systems are regarded as the best way to improve the sustainability of rubber monocultures, but few reports have examined water use in such systems. Accordingly, we tested whether interplanting facilitates water utilization of rubber trees using stable isotope (δD, δ(18)O, and δ(13)C) methods and by measuring soil water content (SWC), shoot potential, and leaf C and N concentrations in a Hevea-Flemingia agroforestry system in Xishuangbanna, southwestern China. We detected a big difference in the utilization of different soil layer water between both species in this agroforestry system, as evidenced by the opposite seasonal fluctuations in both δD and δ(18)O in stem water. However, similar predawn shoot potential of rubber trees at both sites demonstrating that the interplanted species did not affect the water requirements of rubber trees greatly. Rubber trees with higher δ(13)C and more stable physiological indexes in this agroforestry system showed higher water use efficiency (WUE) and tolerance ability, and the SWC results suggested this agroforestry is conductive to water conservation. Our results clearly indicated that intercropping legume plants with rubber trees can benefit rubber trees own higher N supply, increase their WUE and better utilize soil water of each soil layer. PMID:26781071

  17. Riparian reforestation: are there changes in soil carbon and soil microbial communities?

    PubMed

    Mackay, J E; Cunningham, S C; Cavagnaro, T R

    2016-10-01

    Reforestation of pastures in riparian zones has the potential to decrease nutrient runoff into waterways, provide both terrestrial and aquatic habitat, and help mitigate climate change by sequestering carbon (C). Soil microbes can play an important role in the soil C cycle, but are rarely investigated in studies on C sequestration. We surveyed a chronosequence (0-23years) of mixed-species plantings in riparian zones to investigate belowground (chemical and biological) responses to reforestation. For each planting, an adjacent pasture was surveyed to account for differences in soil type and land-use history among plantings. Two remnant woodlands were included in the survey as indicators of future potential of plantings. Both remnant woodlands had significantly higher soil organic C (SOC) content compared with their adjacent pastures. However, there was no clear trend in SOC content among plantings with time since reforestation. The substantial variability in SOC sequestration among plantings was possibly driven by differences in soil moisture among plantings and the inherent variability of SOC content among reference pastures adjacent to plantings. Soil microbial phospholipid fatty acids (PLFA, an indicator of microbial biomass) and activities of decomposition enzymes (β-glucosidase and polyphenol oxidase) did not show a clear trend with increasing planting age. Despite this, there were positive correlations between total SOC concentration and microbial indicators (total PLFA, fungal PLFA, bacterial PLFA and activities of decomposition enzymes) across all sites. The soil microbial community compositions (explored using PLFA markers) of older plantings were similar to those of remnant woodlands. There was a positive correlation between the soil carbon:nitrogen (C:N) and fungal:bacterial (F:B) ratios. These data indicate that in order to maximise SOC sequestration, we need to take into account not only C inputs, but the microbial processes that regulate SOC cycling

  18. Understory vegetation leads to changes in soil acidity and in microbial communities 27 years after reforestation.

    PubMed

    Fu, Xiaoli; Yang, Fengting; Wang, Jianlei; Di, Yuebao; Dai, Xiaoqin; Zhang, Xinyu; Wang, Huimin

    2015-01-01

    Experiments with potted plants and removed understories have indicated that understory vegetation often affects the chemical and microbial properties of soil. In this study, we examined the mechanism and extent of the influence of understory vegetation on the chemical and microbial properties of soil in plantation forests. The relationships between the vegetational structure (diversity for different functional layers, aboveground biomass of understory vegetation, and species number) and soil properties (pH, microbial community structure, and levels of soil organic carbon, total nitrogen, and inorganic nitrogen) were analyzed across six reforestation types (three pure needleleaf forests, a needle-broadleaf mixed forest, a broadleaf forest, and a shrubland). Twenty-seven years after reforestation, soil pH significantly decreased by an average of 0.95 across reforestation types. Soil pH was positively correlated with the aboveground biomass of the understory. The levels of total, bacterial, and fungal phospholipid fatty acids, and the fungal:bacterial ratios were similar in the shrubland and the broadleaf forest. Both the aboveground biomass of the understory and the diversity of the tree layer positively influenced the fungal:bacterial ratio. Improving the aboveground biomass of the understory could alleviate soil acidification. An increase in the aboveground biomass of the understory, rather than in understory diversity, enhanced the functional traits of the soil microbial communities. The replacement of pure plantations with mixed-species stands, as well as the enhancement of understory recruitment, can improve the ecological functions of a plantation, as measured by the alleviation of soil acidification and increased fungal dominance. PMID:25261818

  19. [Control of Soil Nutrient Loss of Typical Reforestation Patterns Along the Three Gorges Reservoir Area].

    PubMed

    Wu, Dong; Huang, Zhi-lin; Xiao, Wen-fa; Zeng, Li-xiong

    2015-10-01

    Annual soil nutrient loss characteristics on typical reforestation patterns in watershed along the Three Gorges Reservoir Area were studied based on runoff plot experiment. Runoff and sediment nutrition content from May to October 2014 of typical reforestation patterns including garden plot (tea garden), forest land (Chinese chestnut) and the original slope farmland were determined and then analyzed. The results showed that: (1) After the Returning Farmland to Forest Project the quantity of annual soil nutrient (nitrogen and phosphorus, the sum of them in sediment and runoff) loss decreased. The output of total nitrogen (TN) was in the order of slope farmland (2 444.27 g x hm(-2)) > tea garden (998.70 g x hm(-2)) > Chinese chestnut forest (532.61 g x hm(-2)), and for total phosphorus (TP) loss was slope farmland (1 690.48 g x hm(-2)) > tea garden (488.06 g x hm(-2)) > Chinese chestnut forest (129.00 g x hm(-2)) . Compared with slope farmland, the load of TN and TP output of reforestation patterns decreased 68.68% and 81.75%, respectively. (2) Compared with slope farmland, available nitrogen loss decreased in reforestation patterns. Total nitrate nitrogen (NO3(-)-N) loss ranked in the order of slope farmland (113.79 g x hm(-2)) > tea garden (73.75 g x hm(-2)) > Chinese chestnut forest (56.06 g x hm(-2)) The largest amount of ammonium nitrogen (NH4(+)-N) was found in tea garden (69.34 g x hm(-2)), then in farmland (52.45 g x hm(-2)), and the least in Chinese chestnut forest (47.23 g x hm(-2)). (3) The main route of NO3(-)-N and NH4(+)-N loss was both through runoff, the quantity of NO3(-)-N and NH4(+)-N output in which accounted for 91.4% and 92.2% of the total, respectively. The quantity of TN and TP in sediment accounted for 86.6% and 98.4% of the total. TN and TP loss showed an extremely significant correlation with sediments, which showed that sediment output was the main approach of TN and TP loss. PMID:26841618

  20. Modelling the impact of agroforestry on hydrology of Mara River basin in East Africa using a distributed model

    NASA Astrophysics Data System (ADS)

    Mwangi, Hosea; Julich, Stefan; Patil, Sopan; McDonald, Morag; Feger, Karl-Heinz

    2016-04-01

    Land use change is one of the main drivers of change of watershed hydrology. The effect of forestry related land use changes (e.g., afforestation, deforestation, agroforestry) on watershed hydrology depends on climate, watershed characteristics and watershed scale. The Soil and Water Assessment Tool (SWAT) model was calibrated, validated and used to simulate the impact of agroforestry on the water balance in Mara River Basin (MRB) in East Africa. Model performance was assessed by Nash-Sutcliffe Efficiency (NSE) and Kling-Gupta Efficiency (KGE). The NSE (and KGE) values for calibration and validation were 0.77 (0.88) and 0.74 (0.85) for the Nyangores sub-watershed and 0.78 (0.89) and 0.79 (0.63) for the entire MRB. It was found that agroforestry in the catchment would generally reduce surface runoff, mainly due to enhanced infiltration. However, it would also increase evapotranspiration and consequently reduce the baseflow and the overall water yield, which was attributed to increased water use by trees. Spatial scale was found to have a significant effect on water balance; the impact of agroforestry was higher at the smaller headwater catchment (Nyangores) than for the larger watershed (entire MRB). However, the rate of change in water yield with increase in area under agroforestry was different for the two and could be attributed to the spatial variability of climate within MRB. Our results suggest that direct extrapolation of the findings from a small sub-catchment to a larger watershed may not always be accurate. These findings could guide watershed managers on the level of trade-offs to make between reduced water yields and other benefits (e.g., soil erosion control, improved soil productivity) offered by agroforestry.

  1. SIGNAL : Water vapour flux variability and local wind field investigations within five differently managed agroforestry sites across Germany

    NASA Astrophysics Data System (ADS)

    Markwitz, Christian; Siebicke, Lukas; Knohl, Alexander

    2016-04-01

    Optimising soil water uptake and ground water consumption in mono-specific agricultural systems plays an important role for sustainable land management. By including tree alleys into the agricultural landscape, called agroforestry (AF), the wind flow is modified leading to a presumably favourable microclimate behind the tree alleys. We expect that this zone is characterized by increased air temperature and atmospheric water vapour content, compared to mono-specific fields. This would extend the growing season and increase the yield production behind the tree alleys. Within the SIGNAL (Sustainable Intensification of Agriculture through Agroforestry) project the evapotranspiration (ET) variability and the local wind field of agroforestry sites compared to mono-specific agricultural systems is investigated. Our study is based on the comparison of five differently managed agroforestry sites across Germany. All site feature one agroforestry plot and one reference plot, which represents a mono-specific cropped system. Each plot is equipped with an eddy-covariance tower, including a high frequency 3D SONIC anemometer and instruments gathering standard meteorological parameter as pressure, temperature, relative humidity, precipitation, ground heat flux, net- and global radiation. The Surface Energy Budget (SEB) method will be used to calculate evapotranspiration QE as QE = ‑ QN ‑ QH ‑ QG ‑ Res by measuring the sensible heat flux, QH, with the eddy covariance method, the radiation balance, QN and the ground heat flux, QG. QH and QN will be measured continuously long-term. We will quantify site specific energy balance non-closure, Res, by temporarily measuring QE, using eddy covariance and a roving tower and then solving the SEB equation for Res. The short term Res will be used to then continuously derive QE from the SEB method. We will compare measured evapotranspiration rates from the SEB method to modelled evapotranspiration of the agroforestry systems through

  2. Effect of Afforestation and Reforestation of Pastures on the Activity and Population Dynamics of Methanotrophic Bacteria▿

    PubMed Central

    Singh, Brajesh K.; Tate, Kevin R.; Kolipaka, Gokul; Hedley, Carolyn B.; Macdonald, Catriona A.; Millard, Peter; Murrell, J. Colin

    2007-01-01

    We investigated the effect of afforestation and reforestation of pastures on methane oxidation and the methanotrophic communities in soils from three different New Zealand sites. Methane oxidation was measured in soils from two pine (Pinus radiata) forests and one shrubland (mainly Kunzea ericoides var. ericoides) and three adjacent permanent pastures. The methane oxidation rate was consistently higher in the pine forest or shrubland soils than in the adjacent pasture soils. A combination of phospholipid fatty acid (PLFA) and stable isotope probing (SIP) analyses of these soils revealed that different methanotrophic communities were active in soils under the different vegetations. The C18 PLFAs (signature of type II methanotrophs) predominated under pine and shrublands, and C16 PLFAs (type I methanotrophs) predominated under pastures. Analysis of the methanotrophs by molecular methods revealed further differences in methanotrophic community structure under the different vegetation types. Cloning and sequencing and terminal-restriction fragment length polymorphism analysis of the particulate methane oxygenase gene (pmoA) from different samples confirmed the PLFA-SIP results that methanotrophic bacteria related to type II methanotrophs were dominant in pine forest and shrubland, and type I methanotrophs (related to Methylococcus capsulatus) were dominant in all pasture soils. We report that afforestation and reforestation of pastures caused changes in methane oxidation by altering the community structure of methanotrophic bacteria in these soils. PMID:17574997

  3. Reforestation as a post-mining land use in the Midwest

    SciTech Connect

    Parr, D.E.

    1982-12-01

    With the passage of the Surface Mining Control and Reclamation Act of 1977 (P.L. 95-87), some very stringent requirements for the successful establishment of trees and shrubs have come into effect. In response to these requirements, AMAX Coal Company is developing a reforestation program for seven surface mines in Indiana and Illinois using the best technology currently available. The program emphasizes obtaining good quality stock, the proper care and handling of stock, the proper planting of the stock, and an effective weed control program. The value of weed control for the establishment and growth of hardwoods has long been recognized in the forest industry, but has not been used extensively in the reforestation of surface mined lands. The improved survival of tree seedlings with the use of weed control justifies the additional cost. Weed control also enhances the growth of tree seedlings. However, the long term growth of seedlings is questionable due to the compaction resulting from the extensive grading required to achieve approximate original contour. To minimize compaction, a forest area in Illinois is being minimally graded only to the extent necessary for environmental stability. Minimal grading is designed to reduce compaction which in turn will promote the development of a more productive forest resource.

  4. Challenges of reforestation in a water limited world under climate change

    NASA Astrophysics Data System (ADS)

    Mátyás, Csaba; Sun, Ge

    2014-05-01

    The debate on the ecological benefits of planted forests at the sensitive lower edge of the closed forest belt (at the "xeric limits") is still unresolved. Forests sequester atmospheric carbon dioxide, control water erosion and dust storms, reduce river sedimentation, and mitigate small floods. However, planting trees in areas previously predominantly occupied by grassland or agriculture can dramatically alter the energy and water balance at multiple scales. The forest/grassland transition zone is especially vulnerable to projected drastic temperature and precipitation shifts under future climate change and variability due to its high ecohydrological sensitivity. The study investigates some of the relevant aspects of the ecological and climatic role of plantation forests and potential impacts at the dryland edges of the temperate zone, using case studies from three countries/regions on three continents. We found that, contrary to popular expectations, the effect of forest cover on regional climate might be limited and the influence of reforestation on water resources might turn into negative. Planted forests generally reduce stream flow and lower groundwater table level because of higher water use than previous land cover types. Increased evaporation potential due to global warming and/or extreme drought events likely reduce areas that are appropriate for tree growth and forest establishment. Ecologically conscious forest policy on management, silviculture and reforestation planning requires the consideration of local hydrologic conditions, future climatic conditions, and also of non-forest alternatives of land use. Keywords: drylands, xeric limits, trailing limits, ecohydrology, climate forcing, land use change, forest policy

  5. Response of methanotrophic communities to afforestation and reforestation in New Zealand.

    PubMed

    Nazaries, Loïc; Tate, Kevin R; Ross, Des J; Singh, Jagrati; Dando, John; Saggar, Surinder; Baggs, Elizabeth M; Millard, Peter; Murrell, J Colin; Singh, Brajesh K

    2011-11-01

    Methanotrophs use methane (CH(4)) as a carbon source. They are particularly active in temperate forest soils. However, the rate of change of CH(4) oxidation in soil with afforestation or reforestation is poorly understood. Here, soil CH(4) oxidation was examined in New Zealand volcanic soils under regenerating native forests following burning, and in a mature native forest. Results were compared with data for pasture to pine land-use change at nearby sites. We show that following soil disturbance, as little as 47 years may be needed for development of a stable methanotrophic community similar to that in the undisturbed native forest soil. Corresponding soil CH(4)-oxidation rates in the regenerating forest soil have the potential to reach those of the mature forest, but climo-edaphic fators appear limiting. The observed changes in CH(4)-oxidation rate were directly linked to a prior shift in methanotrophic communities, which suggests microbial control of the terrestrial CH(4) flux and identifies the need to account for this response to afforestation and reforestation in global prediction of CH(4) emission. PMID:21593799

  6. Effect of afforestation and reforestation of pastures on the activity and population dynamics of methanotrophic bacteria.

    PubMed

    Singh, Brajesh K; Tate, Kevin R; Kolipaka, Gokul; Hedley, Carolyn B; Macdonald, Catriona A; Millard, Peter; Murrell, J Colin

    2007-08-01

    We investigated the effect of afforestation and reforestation of pastures on methane oxidation and the methanotrophic communities in soils from three different New Zealand sites. Methane oxidation was measured in soils from two pine (Pinus radiata) forests and one shrubland (mainly Kunzea ericoides var. ericoides) and three adjacent permanent pastures. The methane oxidation rate was consistently higher in the pine forest or shrubland soils than in the adjacent pasture soils. A combination of phospholipid fatty acid (PLFA) and stable isotope probing (SIP) analyses of these soils revealed that different methanotrophic communities were active in soils under the different vegetations. The C18 PLFAs (signature of type II methanotrophs) predominated under pine and shrublands, and C16 PLFAs (type I methanotrophs) predominated under pastures. Analysis of the methanotrophs by molecular methods revealed further differences in methanotrophic community structure under the different vegetation types. Cloning and sequencing and terminal-restriction fragment length polymorphism analysis of the particulate methane oxygenase gene (pmoA) from different samples confirmed the PLFA-SIP results that methanotrophic bacteria related to type II methanotrophs were dominant in pine forest and shrubland, and type I methanotrophs (related to Methylococcus capsulatus) were dominant in all pasture soils. We report that afforestation and reforestation of pastures caused changes in methane oxidation by altering the community structure of methanotrophic bacteria in these soils. PMID:17574997

  7. Numerical simulation of the impact of reforestation on winter meteorology and environment in a semi-arid urban valley, Northwestern China.

    PubMed

    Yu, Ye; He, Jianjun; Zhao, Suping; Liu, Na; Chen, Jinbei; Mao, Hongjun; Wu, Lin

    2016-11-01

    Since 1999 Chinese government has made great effort to reforest the south and north mountains surrounding urban Lanzhou - a city located in a river valley, Northwestern China. Until 2009 obvious land use change occurred, with 69.2% of the reforested area been changed from grasslands, croplands, barren or sparsely vegetated land to closed shrublands and 20.6% from closed shrublands, grasslands, and croplands to forests. Reforestation changes land-surface properties, with possible impact on the evolution of atmospheric variables. To understand to what extent the local meteorology and environment could be affected by reforestation in winter, and through what processes, two sets of simulations were conducted using the Weather Research and Forecasting model (WRF) and the FLEXible PARTicle (FLEXPART) dispersion model for a control case with high-resolution remotely sensed land cover data for 2009 and a scenario assuming no reforestation since 1999. Results suggested that the changes in albedo, surface exchange coefficient and surface soil heat conductivity related to reforestation led to the changes in surface net radiation and surface energy partitioning, which in turn affected the meteorological fields and enhanced the mountain-valley wind circulation. Replacement of shrublands and grassland with forest in the south mountain through reforestation play a dominant role in the enhancement of mountain-valley wind circulation. Reforestation increased the amount of air exchanged between the valley and the outside during the day, with the largest hourly increase of 10% on calm weather days and a monthly mean hourly increase of 2% for the study period (Dec. 2009). Reforestation affected the spatial distribution of pollutants and slightly improved the urban air quality, especially in the eastern valley. Results from this study provide useful information for future urban air quality management and reforestation plan, and some experience for cities with similar situations in the

  8. Microbial community diversity in agroforestry and grass vegetative filter strips

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vegetative filter strips (VFS) have long been promoted as a soil conservation practice that yields many additional environmental benefits. Most previous studies have focused primarily on the role of vegetation and/or soil physical properties in these ecosystem services. Few studies have investigated...

  9. Microbial Community Diversity in Agroforestry and Grass Buffer Systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agroforesty and grass buffer systems have long been promoted as a soil conservation practice that yields many environmental benefits. Previous research has described the ability of buffer systems to retain nutrients, slow water flow and soil erosion, or mitigate the potentially harmful effects of e...

  10. Modeling and validation of directional reflectance for heterogeneous agro-forestry scenarios

    NASA Astrophysics Data System (ADS)

    Yelu, Z.; Jing, L.; Qinhuo, L.; Huete, A. R.

    2015-12-01

    Landscape heterogeneity is a common natural phenomenon but is seldom considered in current radiative transfer models for predicting the surface reflectance. This paper developed an explicit analytical Radiative Transfer model for heterogeneous Agro-Forestry scenarios (RTAF) by dividing the scenario into non-boundary regions and boundary regions. The scattering contribution of the non-boundary regions that are treated as homogeneous canopies can be estimated from the SAILH model, whereas that of the boundary regions with lengths, widths, canopy heights, and orientations of the field patches, is calculated based on the bidirectional gap probability by considering the interactions and mutual shadowing effects among different patches. The hot spot factor is extended for heterogeneous scenarios, the Hapke model for soil anisotropy is incorporated, and the contributions of the direct and diffuse radiation are separately calculated. The multi-angular airborne observations and the Discrete Anisotropic Radiative Transfer (DART) model simulations were used for validating and evaluating the RTAF model over an agro-forestry scenario in Heihe River Basin, China. It indicates that the RTAF model can accurately simulate the hemispherical-directional reflectance factors (HDRFs) of the heterogeneous agro-forestry scenario, with an RMSE of 0.0016 and 0.0179 in the red and near-infrared (NIR) bands, respectively. The RTAF model was compared with two widely used models, the dominant cover type (DCT) model and the spectral linear mixture (SLM) model, which either neglected the interactions and mutual shadowing effects between the shelterbets and crops, or did not account for the contribution of the shelterbets. Results suggest that the boundary effect can significantly influence the angular distribution of the HDRFs, and consequently enlarged the HDRF variations between the backward and forward directions in the principle plane. The RTAF model reduced the maximum relative error from 25

  11. Ethnopedology and soil quality of bamboo (Bambusa sp.) based agroforestry system.

    PubMed

    Arun Jyoti, Nath; Lal, Rattan; Das, Ashesh Kumar

    2015-07-15

    It is widely recognized that farmers' hold important knowledge of folk soil classification for agricultural land for its uses, yet little has been studied for traditional agroforestry systems. This article explores the ethnopedology of bamboo (Bambusa sp.) based agroforestry system in North East India, and establishes the relationship of soil quality index (SQI) with bamboo productivity. The study revealed four basic folk soil (mati) types: kalo (black soil), lal (red soil), pathal (stony soil) and balu (sandy soil). Of these, lal mati soil was the most predominant soil type (~ 40%) in bamboo-based agroforestry system. Soil physio-chemical parameters were studied to validate the farmers' soil hierarchal classification and also to correlate with productivity of the bamboo stand. Farmers' hierarchal folk soil classification was consistent with the laboratory scientific analysis. Culm production (i.e. measure of productivity of bamboo) was the highest (27culmsclump(-1)) in kalo mati (black soil) and the lowest (19culmsclump(-1)) in balu mati (sandy soil). Linear correlation of individual soil quality parameter with bamboo productivity explained 16 to 49% of the variability. A multiple correlation of the best fitted linear soil quality parameter (soil organic carbon or SOC, water holding capacity or WHC, total nitrogen) with productivity improved explanatory power to 53%. Development of SQI from ten relevant soil quality parameters and its correlation with bamboo productivity explained the 64% of the variation and therefore, suggest SQI as the best determinant of bamboo yield. Data presented indicate that the kalo mati (black soil) is sustainable or sustainable with high input. However, the other three folk soil types (red, stony and sandy soil) are also sustainable but for other land uses. Therefore, ethnopedological studies may move beyond routine laboratory analysis and incorporate SQI for assessing the sustainability of land uses managed by the farmers'. Additional

  12. Reboisement des Terres Arides. (Reforestation in Arid Lands. Manual M5A). Appropriate Technologies for Development Series.

    ERIC Educational Resources Information Center

    Palmer, Virginia C., Ed.

    This is the French translation for a manual which presents some current, state-of-the-art examples of forestry programs in West Africa. It is based on the collective experiences of foresters and of local farmers and herders. Since many of the problems of reforestation of dry areas are the same worldwide, the text (which focuses on the broad…

  13. Reforestation in a high-CO2 world -- Higher mitigation potential than expected, lower adaptation potential than hoped for

    NASA Astrophysics Data System (ADS)

    Sonntag, Sebastian; Pongratz, Julia; Reick, Christian H.; Schmidt, Hauke

    2016-06-01

    We assess the potential and possible consequences for the global climate of a strong reforestation scenario for this century. We perform model experiments using the Max Planck Institute Earth System Model (MPI-ESM), forced by fossil-fuel CO2 emissions according to the high-emission scenario Representative Concentration Pathway (RCP) 8.5, but using land use transitions according to RCP4.5, which assumes strong reforestation. Thereby, we isolate the land use change effects of the RCPs from those of other anthropogenic forcings. We find that by 2100 atmospheric CO2 is reduced by 85 ppm in the reforestation model experiment compared to the reference RCP8.5 model experiment. This reduction is higher than previous estimates and is due to increased forest cover in combination with climate and CO2 feedbacks. We find that reforestation leads to global annual mean temperatures being lower by 0.27 K in 2100. We find large annual mean warming reductions in sparsely populated areas, whereas reductions in temperature extremes are also large in densely populated areas.

  14. Fog water collection and reforestation at mountain locations in a western Mediterranean basin region

    NASA Astrophysics Data System (ADS)

    Valiente, Ja; Estrela, Mj; Corell, D.; Fuentes, D.; Valdecantos, A.

    2010-07-01

    Previous studies carried out by the authors have shown the potential of fog water collection at several mountain locations in the Valencia region (western Mediterranean basin). This coastal region features typical conditions for a dry Mediterranean climate characterized by a pluviometric regime ranging from 400 to 600 mm with a strong annual dependence. Dry conditions together with land degradation that frequently results after recurrent fires occurred in the past make a difficult self-recovery for native forest vegetation so that some kind of human intervention is always recommended. In plots reforested with Mediterranean woody species, periods of more than 120 days without significant precipitation (>5 mm) result in mortality rates above 80% during the first summer in the field. The good potential of fog-water collection at certain mountain locations is considered in this study as an easily available water resource for the reforestation of remote areas where native vegetation cannot be reestablished by itself. A large flat panel made of UV-resistant HD-polyethylene monofilament mesh was deployed at a mountain location for bulk fog water harvesting. Water was stored in high-capacity tanks for the whole length of the experimental campaign and small timely water pulses localized deep in the planting holes were conducted during the summer dry periods. Survival rates and seedling performance of two forest tree species, Pinus pinaster and Quercus ilex, were quantified and correlated to irrigation pulses in a reforestation plot that took an area of about 2500 m2 and contained 620 1-year-old plants. Before and concurrently to the flat panel deployment, a passive omnidirectional fog-water collector of cylindrical shape was set in the area in combination to other environmental instruments such as a rain gauge, a wind direction and velocity sensor and a temperature and humidity probe. Proper orientation of the large flat panel was possible once the direction of local winds

  15. Comparative studies of the associated soil moisture regimes and their productivity in an agroforestry system

    SciTech Connect

    Bhaskar, V.; Rao, N.S.; Reddy, B.G.; Vedavyasa, K.; Ravishankar, H.M.; Venkatesh, R.

    1992-12-31

    Results are presented on the effects of Eucalyptus hybrid, Casuarina equisetifolia, Dalbergia sissoo and Acacia nilotica on certain field crops (finger millet, redgram, horsegram and castor) under dryland conditions. Eucalyptus hybrid showed the maximum border effect on field crops, followed by D. sissoo. C. equisetifolia and A. nilotica. The adverse effect of Eucalyptus was chiefly due to depletion of moisture in the upper surface layers of the soil, whereas shade and allelopathic effects were negligible. The reduction in the crop yield due to competition by trees has been compared with wood yield from trees. Over a period of three years it was found that with the exception of Acacia, there was distinct economic gain under an agroforestry system as the loss in agricultural crops due to the effect of trees was compensated for by wood yield. However, this gain varied considerably depending upon the tree species, crop combination and the prevailing market price of the wood and crop. Eucalyptus hybrid produced the highest wood yield at the expense of field crops than any other tree species. Hence it is recommended that, where food production is the main objective, preference should be given to species like Castuarina, D. Sissoo and Acacia, which have minimum border effect on agricultural crops for dryland agroforestry systems.

  16. Reforesting severely degraded grassland in the Lesser Himalaya of Nepal: Effects on soil hydraulic conductivity and overland flow production

    NASA Astrophysics Data System (ADS)

    Ghimire, Chandra Prasad; Bonell, Mike; Bruijnzeel, L. Adrian; Coles, Neil A.; Lubczynski, Maciek W.

    2013-12-01

    degraded hillslopes in the Lesser Himalaya challenge local communities as a result of the frequent occurrence of overland flow and erosion during the rainy season and water shortages during the dry season. Reforestation is often perceived as an effective way of restoring predisturbance hydrological conditions but heavy usage of reforested land in the region has been shown to hamper full recovery of soil hydraulic properties. This paper investigates the effect of reforestation and forest usage on field-saturated soil hydraulic conductivities (Kfs) near Dhulikhel, Central Nepal, by comparing degraded pasture, a footpath within the pasture, a 25 year old pine reforestation, and little disturbed natural forest. The hillslope hydrological implications of changes in Kfs with land-cover change were assessed via comparisons with measured rainfall intensities over different durations. High surface and near-surface Kfs in natural forest (82-232 mm h-1) rule out overland flow occurrence and favor vertical percolation. Conversely, corresponding Kfs for degraded pasture (18-39 mm h-1) and footpath (12-26 mm h-1) were conducive to overland flow generation during medium- to high-intensity storms and thus to local flash flooding. Pertinently, surface and near-surface Kfs in the heavily used pine forest remained similar to those for degraded pasture. Estimated monsoonal overland flow totals for degraded pasture, pine forest, and natural forest were 21.3%, 15.5%, and 2.5% of incident rainfall, respectively, reflecting the relative ranking of surface Kfs. Along with high water use by the pines, this lack of recovery of soil hydraulic properties under pine reforestation is shown to be a critical factor in the regionally observed decline in base flows following large-scale planting of pines and has important implications for regional forest management.

  17. POTENTIAL OF FORESTRY AND AGROFORESTRY PRACTICES TO STORE CARBON IN THE TROPICS

    EPA Science Inventory

    Terrestrial vegetation plays a pivotal role in the global carbon cycle. ot only are tremendous amounts of. carbon stored in terrestrial egetation, but large amounts are also actively exchanged,between vegetation and the atmosphere. his suggests that vegetation, and specifically f...

  18. [Genetic structure of the populations of Pallas pine (Pinus pallasiana D. Don) reforested in extreme conditions].

    PubMed

    Korshikov, I I; Krasnoshtan, O V

    2010-01-01

    The paper reports on an intensive reforestation of Pallas pine (Pinus pallasiana D. Don) in post-fire sites in the native Mountainous Crimean populations and around the previously planted seed-producing trees in ore-mining dumps of the Krivoy Rog region. Self-sown progeny growing in the dump is characterized by a better growth and comes to the reproductive development phase earlier compared to that one growing in post-fire forest. Allele variability at 20 allozyme loci is less in self-sown progeny than in the native populations whereas its heterozygosity level is similar. Genetic distance (D(N)) among self-sown progenies in post-fire sites and ore-mining dump is comparable to that of the natural populations. PMID:20608157

  19. The dual Green Revolutions in South Korea: reforestation and agricultural revolution under the authoritarian regime.

    PubMed

    Moon, Manyong

    2012-01-01

    In South Korea, the Green Revolution has been commonly understood as the development and dissemination of new rice varieties ('Tongil' rice) and the rapid increase of rice yield in the 1970s. However, revolutionary success in agriculture was not the only green revolution South Korea experienced; another green revolution lay in the success of reforestation projects. In the 1970s, South Korea's forest greening was closely related to its agricultural revolution in several ways. Therefore, South Korea's Green Revolution was an intrinsically linked double feature of agriculture and forestry. This two-pronged revolution was initiated by scientific research - yet accomplished by the strong administrative mobilization of President Park Chung Hee's regime. The process of setting goals and meeting them through a military-like strategy in a short time was made possible under the authoritarian regime, known as 'Yushin', though the administration failed to fully acknowledge scientific expertise in the process of pushing to achieve goals. PMID:22834068

  20. GLOBAL ASSESSMENT OF PROMISING FOREST MANAGEMENT PRACTICES FOR SEQUESTRATION OF CARBON

    EPA Science Inventory

    The assessment produced productivity and cost data for forest and agroforestry management practices in 94 nations. hat is, out of a total of 140 nations in the world with forest resources, about two-thirds are represented in the database at present. he total forest and woodland a...

  1. Reforestation or conservation? The attributes of old growth grasslands in South Africa.

    PubMed

    Zaloumis, Nicholas P; Bond, William J

    2016-09-19

    Deforestation as a result of burning and land conversion in the tropics and subtropics has been widely studied and active restoration of forests has been widely promoted. Besides other benefits, reforestation can sequester carbon thereby reducing CO2 emissions to the atmosphere. However, before grasslands are targeted for 'reforestation', it is necessary to distinguish whether they are ancient natural grasslands or secondary vegetation colonizing deforested areas. Here we report the results of a study comparing primary grasslands in South Africa with 4-40 year old secondary grasslands recovering from afforestation with Pinus species. Primary grasslands had significantly higher plant species richness overall, especially of forb species. Ground cover of primary grasslands was more evenly distributed among species than secondary grasslands which tended to mono-dominance. Forbs with underground storage organs (USOs) were common in primary grasslands but conspicuously absent in the recovering systems. Comparison of secondary grasslands of different ages (up to 40 years) showed negligible recovery of the original species composition. Three key features distinguish old growth primary from secondary grasslands: total and forb species numbers, evenness of species contributions to cover and the presence of USOs. Old growth grasslands also differed in their fire response, showing significant post-burn resprouting and fire-stimulated flowering in contrast to secondary grasslands. Though similar contrasting attributes of ancient and secondary grasslands have been reported in South America, more studies are needed to explore their generality in other geographical regions.This article is part of the themed issue 'Tropical grassy biomes: linking ecology, human use and conservation'. PMID:27502375

  2. Low Herbivory among Targeted Reforestation Sites in the Andean Highlands of Southern Ecuador.

    PubMed

    Adams, Marc-Oliver; Fiedler, Konrad

    2016-01-01

    Insect herbivory constitutes an important constraint in the viability and management of targeted reforestation sites. Focusing on young experimental stands at about 2000 m elevation in southern Ecuador, we examined foliar damage over one season as a function of tree species and habitat. Native tree species (Successional hardwood: Cedrela montana and Tabebuia chrysantha; fast-growing pioneer: Heliocarpus americanus) have been planted among prevailing local landcover types (abandoned pasture, secondary shrub vegetation, and a Pinus patula plantation) in 2003/4. Plantation trees were compared to conspecifics in the spontaneous undergrowth of adjacent undisturbed rainforest matched for height and foliar volume. Specifically, we tested the hypotheses that H. americanus as a pioneer species suffers more herbivory compared to the two successional tree species, and that damage is inversely related to habitat complexity. Overall leaf damage caused by folivorous insects (excluding leafcutter ants) was low. Average leaf loss was highest among T. chrysantha (7.50% ± 0.19 SE of leaf area), followed by H. americanus (4.67% ± 0.18 SE) and C. montana (3.18% ± 0.15 SE). Contrary to expectations, leaf area loss was highest among trees in closed-canopy natural rainforest, followed by pine plantation, pasture, and secondary shrub sites. Harvesting activity of leafcutter ants (Acromyrmex sp.) was strongly biased towards T. chrysantha growing in open habitat (mean pasture: 2.5%; shrub: 10.5%) where it could result in considerable damage (> 90.0%). Insect folivory is unlikely to pose a barrier for reforestation in the tropical Andean mountain forest zone at present, but leafcutter ants may become problematic if local temperatures increase in the wake of global warming. PMID:26963395

  3. Modelling regional land change scenarios to assess land abandonment and reforestation dynamics in the Pyrenees (France)

    USGS Publications Warehouse

    Vacquie, Laure; Houet, Thomas; Sohl, Terry L.; Reker, Ryan; Sayler, Kristi L.

    2015-01-01

    Over the last decades and centuries, European mountain landscapes have experienced substantial transformations. Natural and anthropogenic LULC changes (land use and land cover changes), especially agro-pastoral activities, have directly influenced the spatial organization and composition of European mountain landscapes. For the past sixty years, natural reforestation has been occurring due to a decline in both agricultural production activities and rural population. Stakeholders, to better anticipate future changes, need spatially and temporally explicit models to identify areas at risk of land change and possible abandonment. This paper presents an integrated approach combining forecasting scenarios and a LULC changes simulation model to assess where LULC changes may occur in the Pyrenees Mountains, based on historical LULC trends and a range of future socio-economic drivers. The proposed methodology considers local specificities of the Pyrenean valleys, sub-regional climate and topographical properties, and regional economic policies. Results indicate that some regions are projected to face strong abandonment, regardless of the scenario conditions. Overall, high rates of change are associated with administrative regions where land productivity is highly dependent on socio-economic drivers and climatic and environmental conditions limit intensive (agricultural and/or pastoral) production and profitability. The combination of the results for the four scenarios allows assessments of where encroachment (e.g. colonization by shrublands) and reforestation are the most probable. This assessment intends to provide insight into the potential future development of the Pyrenees to help identify areas that are the most sensitive to change and to guide decision makers to help their management decisions.

  4. Low Herbivory among Targeted Reforestation Sites in the Andean Highlands of Southern Ecuador

    PubMed Central

    Adams, Marc-Oliver; Fiedler, Konrad

    2016-01-01

    Insect herbivory constitutes an important constraint in the viability and management of targeted reforestation sites. Focusing on young experimental stands at about 2000 m elevation in southern Ecuador, we examined foliar damage over one season as a function of tree species and habitat. Native tree species (Successional hardwood: Cedrela montana and Tabebuia chrysantha; fast-growing pioneer: Heliocarpus americanus) have been planted among prevailing local landcover types (abandoned pasture, secondary shrub vegetation, and a Pinus patula plantation) in 2003/4. Plantation trees were compared to conspecifics in the spontaneous undergrowth of adjacent undisturbed rainforest matched for height and foliar volume. Specifically, we tested the hypotheses that H. americanus as a pioneer species suffers more herbivory compared to the two successional tree species, and that damage is inversely related to habitat complexity. Overall leaf damage caused by folivorous insects (excluding leafcutter ants) was low. Average leaf loss was highest among T. chrysantha (7.50% ± 0.19 SE of leaf area), followed by H. americanus (4.67% ± 0.18 SE) and C. montana (3.18% ± 0.15 SE). Contrary to expectations, leaf area loss was highest among trees in closed-canopy natural rainforest, followed by pine plantation, pasture, and secondary shrub sites. Harvesting activity of leafcutter ants (Acromyrmex sp.) was strongly biased towards T. chrysantha growing in open habitat (mean pasture: 2.5%; shrub: 10.5%) where it could result in considerable damage (> 90.0%). Insect folivory is unlikely to pose a barrier for reforestation in the tropical Andean mountain forest zone at present, but leafcutter ants may become problematic if local temperatures increase in the wake of global warming. PMID:26963395

  5. Practice.

    PubMed

    Chambers, David W

    2008-01-01

    Practice refers to a characteristic way professionals use common standards to customize solutions to a range of problems. Practice includes (a) standards for outcomes and processes that are shared with one's colleagues, (b) a rich repertoire of skills grounded in diagnostic acumen, (c) an ability to see the actual and the ideal and work back and forth between them, (d) functional artistry, and (e) learning by doing that transcends scientific rationality. Communities of practice, such as dental offices, are small groups that work together in interlocking roles to achieve these ends. PMID:19413050

  6. Assessment of promising forest-management practices and technologies for enhancing the conservation and sequestration of atmospheric carbon and their costs at the site level

    SciTech Connect

    Dixon, R.K.; Schroeder, P.E.; Winjum, J.K.

    1991-10-01

    The objectives of the report are to assess and synthesize current knowledge on three policy-science topics: (1) Identify promising technologies and practices that could be utilized at technically suitable sites in the world to manage forests and agroforestry systems for sequestering and conserving carbon; (2) Assess available data on costs at the site level for promising forest and agroforestry management practices; and (3) Evaluate estimates of land technically suitable in forested nations and biomes of the world to help meet the Noordwijk forestation targets and the proposed Global Forest Agreement goals.

  7. Projecting the long-term biogeochemical impacts of a diverse agroforestry system in the Midwest

    NASA Astrophysics Data System (ADS)

    Wolz, K. J.; DeLucia, E. H.; Paul, R. F.

    2014-12-01

    Annual, monoculture cropping systems have become the standard agricultural model in the Midwestern US. Unintended consequences of these systems include surface and groundwater pollution, greenhouse gas emissions, loss of biodiversity, and soil erosion. Diverse agroforestry (DA) systems dominated by fruit and nut trees/shrubs have been proposed as an agricultural model for the Midwestern US that can restore ecosystem services while simultaneously providing economically viable and industrially relevant staple food crops. A DA system including six species of fruit and nut crops was established on long-time conventional agricultural land at the University of Illinois at Urbana-Champaign in 2012, with the conventional corn-soybean rotation (CSR) as a control. Initial field measurements of the nitrogen and water cycles during the first two years of transition have indicated a significant decrease in N losses and modification of the seasonal evapotranspiration (ET) pattern. While these early results suggest that the land use transition from CSR to DA can have positive biogeochemical consequences, models must be utilized to make long-term biogeochemical projections in agroforestry systems. Initial field measurements of plant phenology, net N2O flux, nitrate leaching, soil respiration, and soil moisture were used to parameterize the DA system within the DayCENT biogeochemical model as the "savanna" ecosystem type. The model was validated with an independent subset of field measurements and then run to project biogeochemical cycling in the DA system for 25 years past establishment. Model results show that N losses via N2O emission or nitrate leaching reach a minimum within the first 5 years and then maintain this tight cycle into the future. While early ET field measurements revealed similar magnitudes between the DA and CSR systems, modeled ET continued to increase for the DA system throughout the projected time since the trees would continue to grow larger. These modeling

  8. Tree Roots in Agroforestry: Evaluating Biomass and Distribution with Ground Penetrating Radar

    NASA Astrophysics Data System (ADS)

    Borden, Kira Alia

    The root systems of five tree species (Populus deltoides x nigra clone DN-177, Juglans nigra, Quercus rubra, Picea abies, and Thuja occidentalis) are described following non-intrusive imaging using ground penetrating radar (GPR). This research aimed to 1) assess the utility of GPR for in situ root studies and 2) employ GPR to estimate tree root biomass and distribution in an agroforestry system in southern Ontario, Canada. The mean coarse root biomass estimated from GPR analysis was 54.1 +/- 8.7 kg tree-1 (+/- S.E.; n=12), within 1 % of the mean coarse root biomass measured from matched excavations. The vertical distribution of detected roots varied among species, with T. occidentalis and P. abies roots concentrated in the top 20 cm and J. nigra and Q. rubra roots distinctly deeper. I evaluate these root systems based on their C storage potential and complementary root stratification with adjacent crops.

  9. Carbon Storage in Soil Size Fractions Under Two Cacao Agroforestry Systems in Bahia, Brazil

    NASA Astrophysics Data System (ADS)

    Gama-Rodrigues, Emanuela F.; Ramachandran Nair, P. K.; Nair, Vimala D.; Gama-Rodrigues, Antonio C.; Baligar, Virupax C.; Machado, Regina C. R.

    2010-02-01

    Shaded perennial agroforestry systems contain relatively high quantities of soil carbon (C) resulting from continuous deposition of plant residues; however, the extent to which the C is sequestered in soil will depend on the extent of physical protection of soil organic C (SOC). The main objective of this study was to characterize SOC storage in relation to soil fraction-size classes in cacao ( Theobroma cacao L.) agroforestry systems (AFSs). Two shaded cacao systems and an adjacent natural forest in reddish-yellow Oxisols in Bahia, Brazil were selected. Soil samples were collected from four depth classes to 1 m depth and separated by wet-sieving into three fraction-size classes (>250 μm, 250-53 μm, and <53 μm)—corresponding to macroaggregate, microaggregate, and silt-and-clay size fractions—and analyzed for C content. The total SOC stock did not vary among systems (mean: 302 Mg/ha). On average, 72% of SOC was in macroaggregate-size, 20% in microaggregate-size, and 8% in silt-and-clay size fractions in soil. Sonication of aggregates showed that occlusion of C in soil aggregates could be a major mechanism of C protection in these soils. Considering the low level of soil disturbances in cacao AFSs, the C contained in the macroaggregate fraction might become stabilized in the soil. The study shows the role of cacao AFSs in mitigating greenhouse gas (GHG) emission through accumulation and retention of high amounts of organic C in the soils and suggests the potential benefit of this environmental service to the nearly 6 million cacao farmers worldwide.

  10. Relation of the activities of the IPDF/INPE project (reforestation subproject) during the year 1979. [Mato Grosso do Sul, Brazil

    NASA Technical Reports Server (NTRS)

    Dejesusparada, N. (Principal Investigator); Filho, P. H.; Shimabukuro, Y. E.; Demedeiros, J. S.; Desantana, C. C.; Alves, E. C. M.

    1981-01-01

    The state of Mato Grosso do Sul was selected as the study area to define the recognizable classes of Eucalyptus spp. and Pinus spp. by visual and automatic analyses. For visual analysis, a preliminary interpretation key and a legend of 6 groups were derived. Based on these six groups, three final classes were defined for analysis: (1) area prepared for reforestation; (2) area reforested with Eucalyptus spp.; and (3) area reforested with Pinus spp. For automatic interpretation the area along the highway from Ribas do Rio Pardo to Agua Clara was classified into the following classes: eucalytus, bare soil, plowed soil, pine and "cerrado". The results of visual analysis show that 67% of the reforested farms have relative differences in area estimate below 5%, 22%, between 5% and 10%; and 11% between 10% and 20%. The reforested eucalyptus area is 17 times greater than the area of reforested pine. Automatic classification of eucalyptus ranged from 73.03% to 92.30% in the training areas.

  11. Energy farming in Brazil: the role of agroforestry on the production of food and energy from biomass in southeast Bahia

    SciTech Connect

    Alvim, R.

    1983-01-01

    This paper analyzes the problem of fuel production from plants, on the basis of information drawn from the literature and from case studies conducted in Brazil. Special reference is made to the production of charcoal and the production of alcohol and vegetable oils to replace gasoline and diesel fuel. The potential and socioeconomic implications of energy farming are discussed. Diversified plant communities are more stable than monocropping systems in terms of prevention of soil degradation by erosion and leaching, and consequently agroforestry is the safest and the most attractive system for the combined production of food and energy from plants in the humid tropics. Agroforestry is especially interesting in the establishment of perennial energy crops, because it provides earlier cash returns.

  12. Extrapolating soil redistribution rates estimated from 137Cs to catchment scale in a complex agroforestry landscape using GIS

    NASA Astrophysics Data System (ADS)

    Gaspar, Leticia; López-Vicente, Manuel; Palazón, Leticia; Quijano, Laura; Navas, Ana

    2015-04-01

    The use of fallout radionuclides, particularly 137Cs, in soil erosion investigations has been successfully used over a range of different landscapes. This technique provides mean annual values of spatially distributed soil erosion and deposition rates for the last 40-50 years. However, upscaling the data provided by fallout radionuclides to catchment level is required to understand soil redistribution processes, to support catchment management strategies, and to assess the main soil erosion factors like vegetation cover or topography. In recent years, extrapolating field scale soil erosion rates estimated from 137Cs data to catchment scale has been addressed using geostatistical interpolation and Geographical Information Systems (GIS). This study aims to assess soil redistribution in an agroforestry catchment characterized by abrupt topography and an intricate mosaic of land uses using 137Cs data and GIS. A new methodological approach using GIS is presented as an alternative of interpolation tools to extrapolating soil redistribution rates in complex landscapes. This approach divides the catchment into Homogeneous Physiographic Units (HPUs) based on unique land use, hydrological network and slope value. A total of 54 HPUs presenting specific land use, strahler order and slope combinations, were identified within the study area (2.5 km2) located in the north of Spain. Using 58 soil erosion and deposition rates estimated from 137Cs data, we were able to characterize the predominant redistribution processes in 16 HPUs, which represent the 78% of the study area surface. Erosion processes predominated in 6 HPUs (23%) which correspond with cultivated units in which slope and strahler order is moderate or high, and with scrubland units with high slope. Deposition was predominant in 3 HPUs (6%), mainly in riparian areas, and to a lesser extent in forest and scrubland units with low slope and low and moderate strahler order. Redistribution processes, both erosion and

  13. Distribution of throughfall and stemflow in multi-strata agroforestry, perennial monoculture, fallow and primary forest in central Amazonia, Brazil

    NASA Astrophysics Data System (ADS)

    Schroth, Götz; Ferreira da Silva, Luciana; Wolf, Marc-Andree; Geraldes Teixeira, Wenceslau; Zech, Wolfgang

    1999-07-01

    The partitioning of rain water into throughfall, stemflow and interception loss when passing through plant canopies depends on properties of the respective plant species, such as leaf area and branch angles. In heterogeneous vegetation, such as tropical forest or polycultural systems, the presence of different plant species may consequently result in a mosaic of situations with respect to quantity and quality of water inputs into the soil. As these processes influence not only the water availability for the plants, but also water infiltration and nutrient leaching, the understanding of plant effects on the repartitioning of rain water may help in the optimization of land use systems and management practices. We measured throughfall and stemflow in a perennial polyculture (multi-strata agroforestry), monocultures of peach palm (Bactris gasipaes) for fruit and for palmito, a monoculture of cupuaçu (Theobroma grandiflorum), spontaneous fallow and primary forest during one year in central Amazonia, Brazil. The effect on rain water partitioning was measured separately for four useful tree species in the polyculture and for two tree species in the primary forest. Throughfall at two stem distances, and stemflow, differed significantly between tree species, resulting in pronounced spatial patterns of water input into the soil in the polyculture system. For two tree species, peach palm for fruit (Bactris gasipaes) and Brazil nut trees (Bertholletia excelsa), the water input into the soil near the stem was significantly higher than the open-area rainfall. This could lead to increased nutrient leaching when fertilizer is applied close to the stem of these trees. In the primary forest, such spatial patterns could also be detected, with significantly higher water input near a palm (Oenocarpus bacaba) than near a dicotyledonous tree species (Eschweilera sp.). Interception losses were 6·4% in the polyculture, 13·9 and 12·3% in the peach palm monocultures for fruit and for

  14. Survival, reproduction, and recruitment of woody plants after 14 years on a reforested landfill

    NASA Astrophysics Data System (ADS)

    Robinson, George R.; Handel, Steven N.; Schmalhofer, Victoria R.

    1992-03-01

    With the advent of modern sanitary landfill closure techniques, the opportunity exists for transforming municipal landfills into urban woodlands. While costs of fullscale reforestation are generally prohibitive, a modest planting of clusters of trees and shrubs could initiate or accelerate population expansions and natural plant succession from open field to diverse forest. However, among woody species that have been screened for use on landfills, these ecological potentials have not yet been investigated. We examined a 14-yr-old landfill plantation in New Jersey, USA, established to test tolerance of 19 species of trees and shrubs to landfill environments. We measured survivorship, reproduction, and recruitment within and around the experimental installation. Half of the original 190 plants were present, although survival and growth rates varied widely among species. An additional 752 trees and shrubs had colonized the plantation and its perimeter, as well as 2955 stems of vines. However, the great majority (>95%) of woody plants that had colonized were not progeny of the planted cohort, but instead belonged to 18 invading species, mostly native, bird-dispersed, and associated with intermediate stages of secondary plant succession. Based on this evidence, we recommend that several ecological criteria be applied to choices of woody species for the restoration of municipal landfills and similar degraded sites, in order to maximize rapid and economical establishment of diverse, productive woodlands.

  15. Reforestation in southern China: revisiting soil N mineralization and nitrification after 8 years restoration.

    PubMed

    Mo, Qifeng; Li, Zhi'an; Zhu, Weixing; Zou, Bi; Li, Yingwen; Yu, Shiqin; Ding, Yongzhen; Chen, Yao; Li, Xiaobo; Wang, Faming

    2016-01-01

    Nitrogen availability and tree species selection play important roles in reforestation. However, long-term field studies on the effects and mechanisms of tree species composition on N transformation are very limited. Eight years after tree seedlings were planted in a field experiment, we revisited the site and tested how tree species composition affects the dynamics of N mineralization and nitrification. Both tree species composition and season significantly influenced the soil dissolved organic carbon (DOC) and nitrogen (DON). N-fixing Acacia crassicarpa monoculture had the highest DON, and 10-mixed species plantation had the highest DOC. The lowest DOC and DON concentrations were both observed in Eucalyptus urophylla monoculture. The tree species composition also significantly affected net N mineralization rates. The highest rate of net N mineralization was found in A. crassicarpa monoculture, which was over twice than that in Castanopsis hystrix monoculture. The annual net N mineralization rates of 10-mixed and 30-mixed plantations were similar as that of N-fixing monoculture. Since mixed plantations have good performance in increasing soil DOC, DON, N mineralization and plant biodiversity, we recommend that mixed species plantations should be used as a sustainable approach for the restoration of degraded land in southern China. PMID:26794649

  16. A comparative framework of the Erythrina velutina tree species in reforested land and native populations.

    PubMed

    Souza, E M S; Pereira, G S; Silva-Mann, R; Álvares-Carvalho, S V; Ferreira, R A

    2016-01-01

    Erythrina velutina Willd. (Fabaceae: Papillionoideae) is a pioneer species found in tropical and subtropical regions of the world that has medicinal properties and that is used in reforestation projects. This species is rare in some areas of northeastern Brazil. This study aimed to characterize and compare genetic structures of natural and restored populations of E. velutina, with a focus on the selection of tree seeds. A total of 108 individuals from five natural populations and one restored population were analyzed using ISSR markers, resulting in 407 polymorphic fragments. A high rate of polymorphism was observed in the restored population. The highest genetic variability was identified within populations (82%). Genetic bottleneck tests were significant for the Carmópolis/Rosário do Catete and Laranjeiras natural populations along with the Laranjeiras restored population. Genetic distances significantly correlated with spatial distance. Only the restored population retained unique alleles. Similarly, increased genetic distance was observed in individuals of the restored populations compared to the other populations. Observed genetic variation in both natural and restored populations of E. velutina was moderate, thus enabling selection of divergent trees from those trees supplying seeds. Environmental protection and management of these areas is necessary for the maintenance of these individuals and subsequent reproduction. We recommend suggestions for E. velutina conservation, since the restoration model adopted in this study did not promote the development of the specimens until the reproductive stage in a fashion that aims to augment the soil seed bank supply, as is suggested for pioneer species. PMID:27323200

  17. Bottomland hardwood reforestation for neotropical migratory birds: are we missing the forest for the trees?

    USGS Publications Warehouse

    Twedt, D.J.; Portwood, J.

    1997-01-01

    Reforestation of bottomland hardwoods on lands managed for wildlife or timber production has historically emphasized planting heavy-seeded oaks (Quercus spp.). Although techniques have been developed for successful oak establishment, these plantings often require 5 or more years before establishing a 3-dimensional forest structure. We suggest that lands planted to fast-growing early-successional species, in combination with oaks, provide: (1) more expedient benefits to Neotropical migratory birds; (2) greater forest diversity; (3) more rapid economic return to landowners; and (4) enhanced public relations. Under good growing conditions, and with effective weed control, some fast-growing species can develop a substantial 3-dimensional forest structure in as few as 2 or 3 years. Forest-breeding Neotropical migratory birds use stands planted with early successional species several years before sites planted solely with oaks. Where desirable, succession to forests with a high proportion of oak species can be achieved on sites initially planted with fast-growing species through silvicultural management.

  18. Reforestation in southern China: revisiting soil N mineralization and nitrification after 8 years restoration

    PubMed Central

    Mo, Qifeng; Li, Zhi’an; Zhu, Weixing; Zou, Bi; Li, Yingwen; Yu, Shiqin; Ding, Yongzhen; Chen, Yao; Li, Xiaobo; Wang, Faming

    2016-01-01

    Nitrogen availability and tree species selection play important roles in reforestation. However, long-term field studies on the effects and mechanisms of tree species composition on N transformation are very limited. Eight years after tree seedlings were planted in a field experiment, we revisited the site and tested how tree species composition affects the dynamics of N mineralization and nitrification. Both tree species composition and season significantly influenced the soil dissolved organic carbon (DOC) and nitrogen (DON). N-fixing Acacia crassicarpa monoculture had the highest DON, and 10-mixed species plantation had the highest DOC. The lowest DOC and DON concentrations were both observed in Eucalyptus urophylla monoculture. The tree species composition also significantly affected net N mineralization rates. The highest rate of net N mineralization was found in A. crassicarpa monoculture, which was over twice than that in Castanopsis hystrix monoculture. The annual net N mineralization rates of 10-mixed and 30-mixed plantations were similar as that of N-fixing monoculture. Since mixed plantations have good performance in increasing soil DOC, DON, N mineralization and plant biodiversity, we recommend that mixed species plantations should be used as a sustainable approach for the restoration of degraded land in southern China. PMID:26794649

  19. Reforestation with native mixed-species plantings in a temperate continental climate effectively sequesters and stabilizes carbon within decades.

    PubMed

    Cunningham, Shaun C; Cavagnaro, Timothy R; Mac Nally, Ralph; Paul, Keryn I; Baker, Patrick J; Beringer, Jason; Thomson, James R; Thompson, Ross M

    2015-04-01

    Reforestation has large potential for mitigating climate change through carbon sequestration. Native mixed-species plantings have a higher potential to reverse biodiversity loss than do plantations of production species, but there are few data on their capacity to store carbon. A chronosequence (5-45 years) of 36 native mixed-species plantings, paired with adjacent pastures, was measured to investigate changes to stocks among C pools following reforestation of agricultural land in the medium rainfall zone (400-800 mm yr(-1)) of temperate Australia. These mixed-species plantings accumulated 3.09 ± 0.85 t C ha(-1) yr(-1) in aboveground biomass and 0.18 ± 0.05 t C ha(-1) yr(-1) in plant litter, reaching amounts comparable to those measured in remnant woodlands by 20 years and 36 years after reforestation respectively. Soil C was slower to increase, with increases seen only after 45 years, at which time stocks had not reached the amounts found in remnant woodlands. The amount of trees (tree density and basal area) was positively associated with the accumulation of carbon in aboveground biomass and litter. In contrast, changes to soil C were most strongly related to the productivity of the location (a forest productivity index and soil N content in the adjacent pasture). At 30 years, native mixed-species plantings had increased the stability of soil C stocks, with higher amounts of recalcitrant C and higher C:N ratios than their adjacent pastures. Reforestation with native mixed-species plantings did not significantly change the availability of macronutrients (N, K, Ca, Mg, P, and S) or micronutrients (Fe, B, Mn, Zn, and Cu), content of plant toxins (Al, Si), acidity, or salinity (Na, electrical conductivity) in the soil. In this medium rainfall area, native mixed-species plantings provided comparable rates of C sequestration to local production species, with the probable additional benefit of providing better quality habitat for native biota. These results

  20. Simulation of regional temperature change effect of land cover change in agroforestry ecotone of Nenjiang River Basin in China

    NASA Astrophysics Data System (ADS)

    Liu, Tingxiang; Zhang, Shuwen; Yu, Lingxue; Bu, Kun; Yang, Jiuchun; Chang, Liping

    2016-02-01

    The Northeast China is one of typical regions experiencing intensive human activities within short time worldwide. Particularly, as the significant changes of agriculture land and forest, typical characteristics of pattern and process of agroforestry ecotone change formed in recent decades. The intensive land use change of agroforestry ecotone has made significant change for regional land cover, which had significant impact on the regional climate system elements and the interactions among them. This paper took agroforestry ecotone of Nenjiang River Basin in China as study region and simulated temperature change based on land cover change from 1950s to 1978 and from 1978 to 2010. The analysis of temperature difference sensitivity to land cover change based on Weather Research and Forecasting (WRF) model showed that the land cover change from 1950s to 1978 induced warming effect over all the study area, including the change of grassland to agriculture land, grassland to deciduous broad-leaved forest, and deciduous broad-leaved forest to shrub land. The land cover change from 1978 to 2010 induced cooling effect over all the study area, including the change of deciduous broad-leaved forest to agriculture land, grassland to agriculture land, shrub land to agriculture land, and deciduous broad-leaved forest to grassland. In addition, the warming and cooling effect of land cover change was more significant in the region scale than specific land cover change area.

  1. Geomorphological impact on agroforestry systems in the interior highlands of Nicaragua, Central America

    NASA Astrophysics Data System (ADS)

    Mentler, Axel; Wriessnig, Karin; Ottner, Franz; Schomakers, Jasmin; Benavides González, Álvaro; Cisne Contreras, José Dolores; Querol Lipcovich, Daniel

    2013-04-01

    Cerro el Castillo is located in the NW of Nicaragua, Central America, close to the border of Honduras (Provincia Central de las Cordilleras) at 1000-1200m above sea level. In this region, small and medium-sized farms are agroforestry systems with mangos, avocados, coffee, papayas, bananas, strawberries, maize, pumpkins, beans and other vegetables. The production systems are strongly linked to facilities for raising small domestic animals and cows. Main regional agricultural production problems are steep slopes, soil erosion, varying precipitation and distribution, water management and the unstable family income. An investigation of topsoil properties with comparable management systems showed on small scales significant differences in key values of soil chemistry and mineralogy. The outline of the analytical parameters included determination of pH, electrical conductivity (EC), cation exchange capacity (CEC), organic carbon (TOC), dissolved organic carbon (DOC), total nitrogen (TN) and dissolved nitrogen (DN) in soil solution, and plant available nutrients (P and K). The soil's mineralogical composition was determined by X-ray diffraction analysis. The area is a highly weathered karst landscape within a tropical limestone region displaying different amounts of volcanic pyroclastic parent material. The dominant Nitisoils and Andosols show degraded argic and andic horizons along the upper half of the mountainside. The pH values in the topsoil are moderate from pH 5.0 to 5.6. The upland topsoil is decalcified and the amount of plant available phosphorous is very low with significant low Ca concentration at the sorption complex. The mineralogical composition points to the high weathering intensity of this area (high content of kaolinite and a lower concentration of potassium and plagioclase feldspars and andesite). Along the upper half of the mountain, the soil profiles show wider C:N ratios and lower amounts of organic matter. Topsoil at lower altitude and with a lower

  2. Reforestation and landscape reconstruction in gypsum mine area from the semiarid region of NE Brazil

    NASA Astrophysics Data System (ADS)

    Bittar, S. M. B.; Straaten, P. V.; de Araujo Vieura Santos, M. de Fatima; Agra Bezerra da Silva, Y. J.; da Silva, M.; Saraiva de Melo Pinheiro, T.; Gusmao Didier de Moraes, F.; de Aguiar Accioly, A. M.; Alves de Santana, S. R.; dos Santos, H. A.; de Carvalho, D. M.; de Lima Ferreira, G.; de Carvalho Santos, C.

    2012-04-01

    In the Araripe region, Northeast Brazil, exist the world's second largest reserve of gypsum, estimated at over than one billion tons, which accounts for 95% of the Brazilian production and constitutes an important segment of the regional economy. The gypsum deposit occurs in the Lower Cretaceous Santana Formation of the Araripe basin, which is constituted by siltstones, marls, limestones, shales and gypsum layers. The ore extraction is from an open pit, on simple benches with a height of about 15 meters. Activities in mining operations involve stripping, drilling, loading explosives, blast, fragmentation and block loading / transport. Currently, gypsum mining and processing results in major changes in the landscape (pits and wastes heaps sedimentary rocks and soil mixture), deforestation of the "caatinga" ecosystem for use as firewood in small calcinations, dust pollution and changes in hydrology. To promote environmental remediation of this area, a multidisciplinary research has being done with the aim to support reforestation at the wastes heaps. The study involved the following activities: collection and physical, chemical and mineralogical characterization of mine waste materials; a floristic survey around the mines (botanical identification and measuring physical parameters in 16 plots, in order to identify which species are best suited to the conditions of the substrate at the mine site); an experiment (randomized block design) developed in a greenhouse, where seedlings of various native tree species were grown in a "constructed soil" made up of gypsum waste combined with chicken, goat and cattle manure, aimed to select tree species and soil treatment to be used in a waste heap; and an assessment of water quality for irrigation of the reforestation areas. The waste materials consist of large clayey aggregates, which may present physical/chemical properties unfavorable for plant development. The mineralogy of the sand fraction (> 85% quartz, gypsum and

  3. Native American depopulation, reforestation, and fire regimes in the Southwest United States, 1492–1900 CE

    PubMed Central

    Liebmann, Matthew J.; Farella, Joshua; Roos, Christopher I.; Stack, Adam; Martini, Sarah

    2016-01-01

    Native American populations declined between 1492 and 1900 CE, instigated by the European colonization of the Americas. However, the magnitude, tempo, and ecological effects of this depopulation remain the source of enduring debates. Recently, scholars have linked indigenous demographic decline, Neotropical reforestation, and shifting fire regimes to global changes in climate, atmosphere, and the Early Anthropocene hypothesis. In light of these studies, we assess these processes in conifer-dominated forests of the Southwest United States. We compare light detection and ranging data, archaeology, dendrochronology, and historical records from the Jemez Province of New Mexico to quantify population losses, establish dates of depopulation events, and determine the extent and timing of forest regrowth and fire regimes between 1492 and 1900. We present a new formula for the estimation of Pueblo population based on architectural remains and apply this formula to 18 archaeological sites in the Jemez Province. A dendrochronological study of remnant wood establishes dates of terminal occupation at these sites. By combining our results with historical records, we report a model of pre- and post-Columbian population dynamics in the Jemez Province. Our results indicate that the indigenous population of the Jemez Province declined by 87% following European colonization but that this reduction occurred nearly a century after initial contact. Depopulation also triggered an increase in the frequency of extensive surface fires between 1640 and 1900. Ultimately, this study illustrates the quality of integrated archaeological and paleoecological data needed to assess the links between Native American population decline and ecological change after European contact. PMID:26811459

  4. Using soil island plantings as dispersal vectors in large area copper tailings reforestation

    SciTech Connect

    Scherer, G.; Everett, R.

    1998-12-31

    The Wenatchee National Forest undertook the reforestation of the 80 acre (35 ha) Holden copper mine tailings of Washington State in 1989 by using 20, one-fourth acre, triangular shaped soil islands as a source of plant propagules targeted for gravel-covered tailings surfaces. The islands were constructed of soil and surface litter transported from a nearby gravel pit, and planted with four species of conifer seedlings, the shrub Sitka alder (Alnus sinuata) and eight species of grasses. Conifer and alder seedlings were also planted in graveled covered tailings with amendments. Since reproductive status of the conifers would not occur for several years, this propagule vector hypothesis was tested by measuring the distances traveled onto the tailings surface by grass seeds. The number of grass shoots established in four treatment blocks in target plots downwind from the soil island source plantings was also determined. After 36 months, grass seed had migrated to a distance of 32 feet (11 m) from the soil island source. Grass shoots were present within 10 feet (3 m) downwind of the soil island, the most frequent being Mountain brome (Bromus marginatus). Among the tree species, lodgepole pine (Pinus contorta) and Sitka alder grew an average of 6 inches (15--16 cm) after 40 months on the soil islands but somewhat less on the tailing surface. By the third growing season, the only tree species in reproductive condition on the tailings was alder. The soil-island technique is successful for grass dispersal and may have potential for conifer and alder migration.

  5. Native American depopulation, reforestation, and fire regimes in the Southwest United States, 1492-1900 CE.

    PubMed

    Liebmann, Matthew J; Farella, Joshua; Roos, Christopher I; Stack, Adam; Martini, Sarah; Swetnam, Thomas W

    2016-02-01

    Native American populations declined between 1492 and 1900 CE, instigated by the European colonization of the Americas. However, the magnitude, tempo, and ecological effects of this depopulation remain the source of enduring debates. Recently, scholars have linked indigenous demographic decline, Neotropical reforestation, and shifting fire regimes to global changes in climate, atmosphere, and the Early Anthropocene hypothesis. In light of these studies, we assess these processes in conifer-dominated forests of the Southwest United States. We compare light detection and ranging data, archaeology, dendrochronology, and historical records from the Jemez Province of New Mexico to quantify population losses, establish dates of depopulation events, and determine the extent and timing of forest regrowth and fire regimes between 1492 and 1900. We present a new formula for the estimation of Pueblo population based on architectural remains and apply this formula to 18 archaeological sites in the Jemez Province. A dendrochronological study of remnant wood establishes dates of terminal occupation at these sites. By combining our results with historical records, we report a model of pre- and post-Columbian population dynamics in the Jemez Province. Our results indicate that the indigenous population of the Jemez Province declined by 87% following European colonization but that this reduction occurred nearly a century after initial contact. Depopulation also triggered an increase in the frequency of extensive surface fires between 1640 and 1900. Ultimately, this study illustrates the quality of integrated archaeological and paleoecological data needed to assess the links between Native American population decline and ecological change after European contact. PMID:26811459

  6. Satellite data-based phenological evaluation of the nationwide reforestation of South Korea.

    PubMed

    Jeong, Su-Jong; Ho, Chang-Hoi; Choi, Sung-Deuk; Kim, Jinwon; Lee, Eun-Ju; Gim, Hyeon-Ju

    2013-01-01

    Through the past 60 years, forests, now of various age classes, have been established in the southern part of the Korean Peninsula through nationwide efforts to reestablish forests since the Korean War (1950-53), during which more than 65% of the nation's forest was destroyed. Careful evaluation of long-term changes in vegetation growth after reforestation is one of the essential steps to ensuring sustainable forest management. This study investigated nationwide variations in vegetation phenology using satellite-based growing season estimates for 1982-2008. The start of the growing season calculated from the normalized difference vegetation index (NDVI) agrees reasonably with the ground-observed first flowering date both temporally (correlation coefficient, r = 0.54) and spatially (r = 0.64) at the 95% confidence level. Over the entire 27-year period, South Korea, on average, experienced a lengthening of the growing season of 4.5 days decade(-1), perhaps due to recent global warming. The lengthening of the growing season is attributed mostly to delays in the end of the growing season. The retrieved nationwide growing season data were used to compare the spatial variations in forest biomass carbon density with the time-averaged growing season length for 61 forests. Relatively higher forest biomass carbon density was observed over the regions having a longer growing season, especially for the regions dominated by young (<30 year) forests. These results imply that a lengthening of the growing season related to the ongoing global warming may have positive impacts on carbon sequestration, an important aspect of large-scale forest management for sustainable development. PMID:23520541

  7. ASSESSMENT OF PROMISING FOREST MANAGEMENT PRACTICES AND TECHNOLOGIES FOR ENHANCING THE CONSERVATION AND SEQUESTRATION OF ATMOSPHERIC CARBON AND THEIR COSTS AT SITE LEVEL

    EPA Science Inventory

    The objectives of this report are to assess and synthesize current knowledge on three policy-science topics: ) Identify promising technologies and practices that could be utilized at technically suitable sites in the world to manage forests and agroforestry systems for sequesteri...

  8. Development Of An Agroforestry Sequestration Project In KhammamDistrict Of India

    SciTech Connect

    Sudha, P.; Ramprasad, V.; Nagendra, M.D.V.; Kulkarni, H.D.; Ravindranath, N.H.

    2007-06-01

    Large potential for agroforestry as a mitigation option hasgiven rise to scientific and policy questions. This paper addressesmethodological issues in estimating carbon sequestration potential,baseline determination, additionality and leakage in Khammam district,Andhra Pradesh, southern part of India. Technical potential forafforestation was determined considering the various landuse options. Forestimating the technical potential, culturable wastelands, fallow andmarginal croplands were considered for Eucalyptus clonal plantations.Field studies for aboveground and below ground biomass, woody litter andsoil organic carbon for baseline and project scenario were conducted toestimate the carbon sequestration potential. The baseline carbon stockwas estimated to be 45.33 tC/ha. The additional carbon sequestrationpotential under the project scenario for 30 years is estimated to be12.82 tC/ha/year inclusive of harvest regimes and carbon emissions due tobiomass burning and fertilizer application. The project scenario thoughhas a higher benefit cost ratio compared to baseline scenario, initialinvestment cost is high. Investment barrier exists for adoptingagroforestry in thedistrict.

  9. Modelling agro-forestry scenarios for ammonia abatement in the landscape

    NASA Astrophysics Data System (ADS)

    Bealey, W. J.; Loubet, B.; Braban, C. F.; Famulari, D.; Theobald, M. R.; Reis, S.; Reay, D. S.; Sutton, M. A.

    2014-12-01

    Ammonia emissions from livestock production can have negative impacts on nearby protected sites and ecosystems that are sensitive to eutrophication and acidification. Trees are effective scavengers of both gaseous and particulate pollutants from the atmosphere making tree belts potentially effective landscape features to support strategies aiming to reduce ammonia impacts. This research used the MODDAS-THETIS a coupled turbulence and deposition turbulence model, to examine the relationships between tree canopy structure and ammonia capture for three source types—animal housing, slurry lagoon, and livestock under a tree canopy. By altering the canopy length, leaf area index, leaf area density, and height of the canopy in the model the capture efficiencies varied substantially. A maximum of 27% of the emitted ammonia was captured by tree canopy for the animal housing source, for the slurry lagoon the maximum was 19%, while the livestock under trees attained a maximum of 60% recapture. Using agro-forestry systems of differing tree structures near ‘hot spots’ of ammonia in the landscape could provide an effective abatement option for the livestock industry that complements existing source reduction measures.

  10. The role of habitat patches on mammalian diversity in cork oak agroforestry systems

    NASA Astrophysics Data System (ADS)

    Rosalino, Luis M.; Rosário, João do; Santos-Reis, Margarida

    2009-07-01

    Habitat patches, depending on the degree of differentiation from the matrix, can add few or many elements to the species pool of a particular landscape. Their importance to biodiversity is particularly relevant in areas with complex landscapes, where natural, naturalized, or managed habitats are interspersed by small patches of habitat types with very different biophysical characteristics; e.g., fruit orchards and riparian areas. This is the case of the montado landscape, a cork oak agroforestry system that largely covers south-western Portugal. We evaluated whether the high mammalian biodiversity found in this system is, in part, the cumulative result of the species found in the non-matrix habitats. Our results indicate that in areas where there are inclusions of orchards/olive yards and riparian vegetation in the cork oak woodland, a significantly higher number of mammalian species are present. We further detected a positive effect of low human disturbance on mammal diversity. Ultimately, our results can be used by managers to augment their management options, since we show that the inclusion and maintenance of non-matrix habitat patches in cork oak agro-silvo-forestry systems can help to maximize mammal biodiversity without compromising services associated with agriculture and forestry.

  11. Canopy development, CO(2) exchange and carbon balance of a modeled agroforestry tree.

    PubMed

    Nygren, P; Kiema, P; Rebottaro, S

    1996-09-01

    We developed a whole-canopy CO(2) exchange simulation model to study effects of pruning on the carbon balance of trees. Model inputs include global short-wave radiation, photosynthetic photon flux density (PFD), air temperature, time series of the development of canopy diameter, height and total leaf area during the simulation period and local geographical and atmospheric parameters. Canopy structure is derived stochastically from the time series of canopy development and growth functions of individual phytoelements. The PFD incident on a phytoelement is computed from the average gap frequency of the canopy and the binary random probability of sunflecks on the phytoelement. Instantaneous CO(2) assimilation rate of each phytoelement is computed from PFD and phytoelement age. Assimilation rates are integrated over space and time to estimate whole-canopy CO(2) assimilation. The model was used to study carbon balance in five sources of the leguminous agroforestry tree Erythrina poeppigiana (Walpers) O.F. Cook during two 6-month pruning intervals. The canopy description appeared to be realistic. According to the simulations, cumulative assimilation did not provide enough carbon for tree growth until two months after pruning, indicating dependence of tree growth on reserve carbohydrates. The two most productive sources, which had the most open canopies, were the most dependent on reserve carbohydrates after pruning. PMID:14871680

  12. Effects of Syn-Pandemic Reforestation on Atmospheric Carbon Dioxide From 1500 to 1700 A.D.

    NASA Astrophysics Data System (ADS)

    Nevle, R. J.; Bird, D. K.

    2005-12-01

    Recent analysis of paleoclimate proxies suggests that biomass burning by humans during the past eight millennia produced quantities of CO2 sufficient to counteract the effects of decreasing insolation driven by orbital variations and thus prevented ice sheet expansion. Correlation between periods of declining population and biomass burning, such as implied by the synchroneity of the American pandemics and decreasing atmospheric CO2 concentration during the 16th-18th centuries, provides an important test of the extent to which pre-industrial anthropogenic activity affected the atmospheric greenhouse gas budget. Numerous studies have attributed the ~5 ppm decline of atmospheric CO2 concentration, as well as the synchronous ~0.1 per mil increase of the δ13C of atmospheric CO2 between 1500 and 1700 A.D., to the effects of Little Ice Age cooling. However, this interpretation is not supported by recent multiproxy-based surface temperature reconstructions, which demonstrate a diminutive global temperature anomaly of ~0.1 C that was unlikely to have independently produced the distinct effect observed in atmospheric CO2 concentration. Alternatively, it is possible that a decline in CO2 concentration driven by massive reforestation produced cooling as a by-product. The timing and magnitude of changes in both the concentration and carbon-isotope composition of atmospheric CO2 recorded by globally distributed climate proxies from the tropics (sponges), temperate latitudes (tree rings), and polar regions (ice cores) are compatible with fixation of >10 Gt C due to reforestation. Reforestation, which explains pre-industrial atmospheric CO2 variations between 1500 and 1700 A.D. in a manner more consistent with the global surface temperature record than explanations requiring substantial cooling, presumably occurred on lands that were cultivated and seasonally burned, then subsequently abandoned, by indigenous Americans who perished in pandemics during European conquest. The

  13. Evaluating the reforested area for the municipality of Buri by automatic analysis of LANDSAT imagery. [Sao Paulo, Brazil

    NASA Technical Reports Server (NTRS)

    Dejesusparada, N. (Principal Investigator); Lee, D. C. L.; Filho, R. H.; Shimabukuro, Y. E.

    1979-01-01

    The author has identified the following significant results. The class of reforestation (Pinus, Eucalyptus, Araucaria) was defined using iterative image analysis (1-100) and LANDSAT MSS data. Estimates of class area by 1-100 were compared with data supplied by the forestry institute in Sao Paulo. LANDSAT channels 4 and 5 served to differentiate the Pinus, Eucalyptus, and Araucaria from the other trees. Channels 6 and 7 gave best results for differentiating between the classes. A good representative spectral response was obtained for Auraucaria on these two channels. The small relative differences obtained were +4.24% for Araucaria, -7.51% for Pinus, and -32.07% for Eucalyptus.

  14. Effects of cultivation and reforestation on suspended sediment concentrations: a case study in a mountainous catchment in China

    NASA Astrophysics Data System (ADS)

    Fang, N. F.; Chen, F. X.; Zhang, H. Y.; Wang, Y. X.; Shi, Z. H.

    2015-08-01

    Understanding how sediment concentrations vary with land use/cover is critical for evaluating the current and future impacts of human activities on river systems. This paper presents suspended sediment concentration (SSC) dynamics and the relationship between SSC and discharge (Q) in the 8973 km2 Du catchment and its sub-catchment (4635 km2). In the Du catchment and its sub-catchment, 4235 and 3980 paired Q-SSC samples, respectively, were collected over 30 years. Under the influence of the "Household Contract Responsibility System" and Grain-for-Green projects in China, three periods were designated, the original period (1980s), cultivation period (1990s), and reforestation period (2000s). The results of a Mann-Kendall test showed that rainfall slightly increased during the study years; however, the annual discharge and sediment load significantly decreased. The annual suspended sediment yield of the Du catchment varied between 4 and 332 kg s-1, and that of the sub-catchment varied between 2 and 135 kg s-1. The SSCs in the catchment and sub-catchment fluctuated between 1 and 22 400 g m-3 and between 1 and 31 800 g m-3, respectively. The mean SSC of the Du catchment was relatively stable during the three periods (±83 g m-3). ANOVA indicated that the SSC did not significantly change under cultivation for low and moderate flows, but was significantly different under high flow during reforestation of the Du catchment. The SSC in the sub-catchment was more variable, and the mean-SSC in the sub-catchment varied from 1058 g m-3 in the 1980s to 1256 g m-3 in the 1990s and 891 g m-3 in the 2000s. Reforestation significantly decreased the SSCs during low and moderate flows, whereas cultivation increased the SSCs during high flow. The sediment rating curves showed a stable relationship between the SSC and Q in the Du catchment during the three periods. However, the SSC-Q of the sub-catchment exhibited scattered relationships during the original and cultivation periods and a

  15. Effects of cultivation and reforestation on suspended sediment concentrations: a case study in a mountainous catchment in China

    NASA Astrophysics Data System (ADS)

    Fang, N. F.; Chen, F. X.; Zhang, H. Y.; Wang, Y. X.; Shi, Z. H.

    2016-01-01

    Understanding how sediment concentrations vary with land use/cover is critical for evaluating the current and future impacts of human activities on river systems. This paper presents suspended sediment concentration (SSC) dynamics and the relationship between SSC and discharge (Q) in the 8973 km2 Du catchment and its sub-catchment (4635 km2). In the Du catchment and its sub-catchment, 4235 and 3980 paired SSC-Q samples, respectively, were collected over 30 years. Under the influence of the Household Contract Responsibility System and Grain-for-Green projects in China, three periods were designated, the original period (1980s), cultivation period (1990s) and reforestation period (2000s). The results of a Mann-Kendall test showed that rainfall slightly increased during the study years; however, the annual discharge and sediment load significantly decreased. The annual suspended sediment yield of the Du catchment varied between 1.3 × 108 and 1.0 × 1010 kg, and that of the sub-catchment varied between 6.3 × 107 and 4.3 × 109 kg. The SSCs in the catchment and sub-catchment fluctuated between 1 and 22400 g m-3 and between 1 and 31800 g m-3, respectively. The mean SSC of the Du catchment was relatively stable during the three periods (±83 g m-3). ANOVA (analysis of variance) indicated that the SSC did not significantly change under cultivation for low and moderate flows, but was significantly different under high flow during reforestation of the Du catchment. The SSC in the sub-catchment was more variable, and the mean SSC in the sub-catchment varied from 1058 ± 2217 g m-3 in the 1980s to 1256 ± 2496 g m-3 in the 1990s and 891 ± 1558 g m-3 in the 2000s. Reforestation significantly decreased the SSCs during low and moderate flows, whereas cultivation increased the SSCs during high flow. The sediment rating curves showed a stable relationship between the SSC and Q in the Du catchment during the three periods. However, the SSC-Q of the sub-catchment exhibited

  16. Biomass production in agroforestry and forestry systems on salt-affected soils in South Asia: exploration of the GHG balance and economic performance of three case studies.

    PubMed

    Wicke, Birka; Smeets, Edward M W; Akanda, Razzaque; Stille, Leon; Singh, Ranjay K; Awan, Abdul Rasul; Mahmood, Khalid; Faaij, Andre P C

    2013-09-30

    This study explores the greenhouse gas balance and the economic performance (i.e. net present value (NPV) and production costs) of agroforestry and forestry systems on salt-affected soils (biosaline (agro)forestry) based on three case studies in South Asia. The economic impact of trading carbon credits generated by biosaline (agro)forestry is also assessed as a potential additional source of income. The greenhouse gas balance shows carbon sequestration over the plantation lifetime of 24 Mg CO2-eq. ha(-1) in a rice-Eucalyptus camaldulensis agroforestry system on moderately saline soils in coastal Bangladesh (case study 1), 6 Mg CO2-eq. ha(-1) in the rice-wheat- Eucalyptus tereticornis agroforestry system on sodic/saline-sodic soils in Haryana state, India (case study 2), and 96 Mg CO2-eq. ha(-1) in the compact tree (Acacia nilotica) plantation on saline-sodic soils in Punjab province of Pakistan. The NPV at a discount rate of 10% is 1.1 k€ ha(-1) for case study 1, 4.8 k€ ha(-1) for case study 2, and 2.8 k€ ha(-1) for case study 3. Carbon sequestration translates into economic values that increase the NPV by 1-12% in case study 1, 0.1-1% in case study 2, and 2-24% in case study 3 depending on the carbon credit price (1-15 € Mg(-1) CO2-eq.). The analysis of the three cases indicates that the economic performance strongly depends on the type and severity of salt-affectedness (which affect the type and setup of the agroforestry system, the tree species and the biomass yield), markets for wood products, possibility of trading carbon credits, and discount rate. PMID:23810966

  17. Dew as an Adaptation Measure to Meet Agricultural and Reforestation Water Demand in a Changing Climate

    NASA Astrophysics Data System (ADS)

    Tomaszkiewicz, Marlene; Abou Najm, Majdi; Alameddine, Ibrahim; El Fadel, Mutasem

    2014-05-01

    Dew harvesting, believed to be an ancient technique, has recently re-emerged as a viable and sustainable water resource. Nightly yields are relatively low, yet non-negligible, and dew events occur more frequently than rainfall promoting its effectiveness, particularly in arid and semi-arid regions. In this study, we demonstrate how dew can be harvested and subsequently used for small-scale irrigation to meet agricultural and reforestation water demand. Polyethylene dew harvesting systems were constructed and placed in the field. Dew was harvested as a result of the radiative cooling during the night, thus allowing dew formation under conditions of high humidity. Condensed dew formed upon the planar surface was collected by gravity. Water demand for selected crops and trees within a pilot study area (Lebanon) was estimated using a deficit irrigation model. Simulations of water demand requirements of various plants and surfaces were performed and compared to dew volumes to assess the ability of the system to meet all or in part the plant water demands across seasons. Data from the polyethylene low-cost dew condensers have shown that within the pilot study, average nightly dew yields were 0.1 L m-2 of condensing surface with a maximum yield of 0.4 L m-2. Dew events occurred generally more frequently than precipitation events, with an estimated 40% of nights producing dew condensate. This translates to 50 mm of equivalent rainfall on average (during dew nights), with a maximum of 200 mm in one night, if one assumes using drip irrigation over a seedling within a 20 cm2 area. Using a simple deficit irrigation model, it was demonstrated that crops such as the tomato plant, which typically has a growing season during the dry summer, can potentially be irrigated solely by dew, thus eliminating the need for traditional irrigation sources. Similarly, young tree seedlings, such as the cedar tree, can depend upon dew as a primary water resource. Moreover, based on similar

  18. Mineral control of soil carbon storage with reforestation of abandoned pastures

    NASA Astrophysics Data System (ADS)

    Marín-Spiotta, E.; Silver, W. L.; Swanston, C. W.; Torn, M. S.; Burton, S. D.

    2006-12-01

    their maximum C storage capacity. This may explain their resiliency to land-use change and why we have observed no significant accumulation of soil C despite large increases in aboveground biomass with reforestation.

  19. Effect of the natural reforestation of an arable land on the organic matter composition in soddy-podzolic soils

    NASA Astrophysics Data System (ADS)

    Erokhova, A. A.; Makarov, M. I.; Morgun, E. G.; Ryzhova, I. M.

    2014-11-01

    The dynamics of the organic matter composition in soddy-podzolic soils during the natural reforestation of an arable land in the southern taiga zone have been discussed. It has been shown that the contents of the total and labile carbon in the old plow horizon increase with the age of the fallow in the chronosequence of soils established in the Parfen'evo district of Kostroma oblast. The parameters characterizing the labile soil organic matter include the contents of the carbon extractable by mild chemical extractants (distilled water, 0.1 M K2SO4 solution, 0.1 M neutral Na4P2O7 solution), the microbial biomass, and the light fraction. The granulo-densimetric fractionation has shown that the contents of carbon in the light and organomineral fractions of the soil vary in the course of the postagrogenic succession. The content of the clay-fraction carbon increases and its portion in the total carbon of the soil decreases at the transition from the plowland to the forest. The reforestation of agrosoddy-podzolic soils enhances the physical protection of the soil organic matter due to the increase in the portion of microaggregate carbon.

  20. Depletion of Stem Water of Sclerocarya birrea Agroforestry Tree Precedes Start of Rainy Season in West African Sudanian Zone

    NASA Astrophysics Data System (ADS)

    Ceperley, Natalie; Mande, Theophile; Parlange, Marc B.

    2013-04-01

    Understanding water use by agroforestry trees in dry-land ecosystems is essential for improving water management. Agroforestry trees are valued and promoted for many of their ecologic and economic benefits but are often criticized as competing for valuable water resources. In order to understand the seasonal patterns of source water used by agroforestry trees, samples from rain, ground, and surface water were collected weekly in the subcatchment of the Singou watershed that is part of the Volta Basin. Soil and vegetation samples were collected from and under a Sclerocarya birrea agroforstry trees located in this catchment in sealed vials, extracted, and analyzed with a Picarro L2130-i CRDS to obtain both δO18 and δDH fractions. Meteorological measurements were taken with a network of wireless, autonomous stations that communicate through the GSM network (Sensorscope) and two complete eddy-covariance energy balance stations, in addition to intense monitoring of sub-canopy solar radiation, throughfall, stemflow, and soil moisture. Examination of the time series of δO18 concentrations confirm that values in soil and xylem water are coupled, both becoming enriched during the dry season and depleted during the rainy season. Xylem water δO18 levels drops to groundwater δO18 levels in early March when trees access groundwater for leafing out, however soil water does not reach this level until soil moisture increases in mid-June. The relationship between the δDH and δO18 concentrations of water extracted from soil and tree samples do not fall along the global meteoric water line. In order to explore whether this was a seasonally driven, we grouped samples into an "evaporated" group or a "meteoric" group based on the smaller residual to the respective lines. Although more soil samples were found along the m-line during the rainy season than tree samples or dry season soil samples, there was no significant difference in days since rain for any group This suggests that

  1. Soil Modification by Native Shrubs Boosts Crop Productivity in Sudano-Sahelian Agroforestry System

    NASA Astrophysics Data System (ADS)

    Bogie, N. A.; Bayala, R.; Diedhiou, I.; Ghezzehei, T. A.; Dick, R.

    2014-12-01

    A changing climate along with human and animal population pressure can have a devastating effect on crop yields and food security in the Sudano-Sahel. Agricultural solutions to address soil degradation and crop water stress are needed to combat this increasingly difficult situation. Significant differences in crop success have been observed in peanut and millet grown in association with two native evergreen shrubs Piliostigma reticulatum, and Guiera senegalensis at the sites of Nioro du Rip and Keur Matar, respectively.We investigate how farmers can increase crop productivity by capitalizing on the evolutionary adaptation of native shrubs to the harsh Sudano-Sahelian environment as well as the physical mechanisms at work in the system that can lead to more robust yields. Soil moisture and water potential data were collected during a dry season millet irrigation experiment where stress was imposed in the intercropped system. Despite lower soil moisture content, crops grown in association with shrubs have increased biomass production and a faster development cycle. Hydraulic redistribution is thought to exist in this system and we found diurnal fluctuations in water potential within the intercropped system that increased in magnitude of to 0.4 Mpa per day as the soil dried below 1.0 Mpa during the stress treatment. An isotopic tracer study investigating hydraulic redistribution was carried out by injecting labeled water into shrub roots and sampling shrubs and nearby crops for isotopic analysis of plant water. These findings build on work that was completed in 2004 at the site, but point to lower overall magnitude of diurnal soil water potential fluctuations in dry soils. Using even the limited resources that farmers possess, this agroforestry technique can be expanded over wide swaths of the Sahel.

  2. Improved fodder tree management in the agroforestry systems of central and western Nepal

    SciTech Connect

    Karki, M.B.

    1992-01-01

    Ten, three year old, fodder tree species were evaluated at four on-station and three on-farm sites in Nepal. Ficus semicordata (Buchattam. ex Sm.) growth was found to be significantly higher than the rest in diameter and dry foliage weight values. Species were significantly different in height, diameter, and foliage and wood growth. Sites were significantly different in total height growth only. On-farm species evaluation indicated that A. lakoocha and F. semicordata had significantly higher growth. Allometric regression equations were developed to predict foliage, total wood, and total biomass yield of F. semicordata, and B. variegata. Individual-tree models were developed. For B. variegata, diameter at 50 cm. and for F. semicordata, crown diameter and height gave the best fitted equations. Regression equations for three sites did not differ significantly. Therefore, data were pooled and a common model was estimated for each species. In on-farm regression models, height and crown diameter were the best predictors for F. semicordata and dbh gave the best fit for B. variegata. The models for the two species were used to construct regional fodder and fuelwood biomass tables. An improved crop-livestock-fodder agroforestry system was designed for a village in Nepal. Linear programming was used to demonstrate the use of a tool to optimize land allocation maximizing net returns while satisfying the supply of minimum needs of food, fodder, and fuelwood. The optimal solution indicated that, by improving the returns to labor and by applying more compost, the village should be able to increase the annual net farm returns from NRs. 2.94 million to NRs. 3.85 million. The food, fodder and fuelwood production levels were shown to increase by 17%, 130%, and 537% respectively. The labor and compost requirements were up by 138% and 59% respectively, over the five year period. The soil loss through run-off was estimated to decrease by about 15% over the same period.

  3. Seasonal isotope hydrology of a coffee agroforestry watershed in Costa Rica

    NASA Astrophysics Data System (ADS)

    Welsh Unwala, K.; Boll, J.; Roupsard, O.

    2014-12-01

    Improved information of seasonal variations in watershed hydrology in the tropics can strengthen models and understanding of hydrology of these areas. Seasonality in the tropics produces rainy seasons versus dry seasons, leading to different hydrologic and water quality processes throughout the year. We questioned whether stable isotopes in water can be used to trace the seasonality in this region, despite experiencing a "drier" season, such as in a Tropical Humid location. This study examines the fluctuations of stable isotope compositions (δ18O and δD) in water balance components in a small (<1 km2) coffee agroforestry watershed located in central Costa Rica on the Caribbean side. Samples were collected in precipitation, groundwater, and stream water for more than two years, across seasons and at an hourly frequency during storm events to better characterize spatial and temporal variations of the isotopic composition and of the respective contribution of surface and deeper groundwater to streamflow in the watershed. Isotope composition in precipitation ranged from -18.5 to -0.3‰ (∂18O) and -136.4 to 13.7‰ (∂D), and data indicate that atmospheric moisture cycling plays an important role in this region. A distinct seasonality was observed in monthly-averaged data between enriched dry season events as compared with the rainy season events. Streamflow data indicate that a deep groundwater system contributes significantly to baseflow, although a shallow, spring-driven system also contributes to stream water within the watershed. During storm events, precipitation contributes to stormflow in the short-term, confirming the role of superficial runoff. These results indicate that isotopes are helpful to partition the water balance even in a Tropical Humid situation where the rainfall seasonality is weak.

  4. The Influence of Agroforestry and Other Land-Use Types on the Persistence of a Sumatran Tiger ( Panthera tigris sumatrae) Population: An Individual-Based Model Approach

    NASA Astrophysics Data System (ADS)

    Imron, Muhammad Ali; Herzog, Sven; Berger, Uta

    2011-08-01

    The importance of preserving both protected areas and their surrounding landscapes as one of the major conservation strategies for tigers has received attention over recent decades. However, the mechanism of how land-use surrounding protected areas affects the dynamics of tiger populations is poorly understood. We developed Panthera Population Persistence (PPP)—an individual-based model—to investigate the potential mechanism of the Sumatran tiger population dynamics in a protected area and under different land-use scenarios surrounding the reserve. We tested three main landscape compositions (single, combined and real land-uses of Tesso-Nilo National Park and its surrounding area) on the probability of and time to extinction of the Sumatran tiger over 20 years in Central Sumatra. The model successfully explains the mechanisms behind the population response of tigers under different habitat landscape compositions. Feeding and mating behaviours of tigers are key factors, which determined population persistence in a heterogeneous landscape. All single land-use scenarios resulted in tiger extinction but had a different probability of extinction within 20 years. If tropical forest was combined with other land-use types, the probability of extinction was smaller. The presence of agroforesty and logging concessions adjacent to protected areas encouraged the survival of tiger populations. However, with the real land-use scenario of Tesso-Nilo National Park, tigers could not survive for more than 10 years. Promoting the practice of agroforestry systems surrounding the park is probably the most reasonable way to steer land-use surrounding the Tesso-Nilo National Park to support tiger conservation.

  5. The influence of agroforestry and other land-use types on the persistence of a Sumatran tiger (Panthera tigris sumatrae) population: an individual-based model approach.

    PubMed

    Imron, Muhammad Ali; Herzog, Sven; Berger, Uta

    2011-08-01

    The importance of preserving both protected areas and their surrounding landscapes as one of the major conservation strategies for tigers has received attention over recent decades. However, the mechanism of how land-use surrounding protected areas affects the dynamics of tiger populations is poorly understood. We developed Panthera Population Persistence (PPP)--an individual-based model--to investigate the potential mechanism of the Sumatran tiger population dynamics in a protected area and under different land-use scenarios surrounding the reserve. We tested three main landscape compositions (single, combined and real land-uses of Tesso-Nilo National Park and its surrounding area) on the probability of and time to extinction of the Sumatran tiger over 20 years in Central Sumatra. The model successfully explains the mechanisms behind the population response of tigers under different habitat landscape compositions. Feeding and mating behaviours of tigers are key factors, which determined population persistence in a heterogeneous landscape. All single land-use scenarios resulted in tiger extinction but had a different probability of extinction within 20 years. If tropical forest was combined with other land-use types, the probability of extinction was smaller. The presence of agroforesty and logging concessions adjacent to protected areas encouraged the survival of tiger populations. However, with the real land-use scenario of Tesso-Nilo National Park, tigers could not survive for more than 10 years. Promoting the practice of agroforestry systems surrounding the park is probably the most reasonable way to steer land-use surrounding the Tesso-Nilo National Park to support tiger conservation. PMID:20967444

  6. Climate-resilient agroforestry: physiological responses to climate change and engineering of crassulacean acid metabolism (CAM) as a mitigation strategy.

    PubMed

    Borland, Anne M; Wullschleger, Stan D; Weston, David J; Hartwell, James; Tuskan, Gerald A; Yang, Xiaohan; Cushman, John C

    2015-09-01

    Global climate change threatens the sustainability of agriculture and agroforestry worldwide through increased heat, drought, surface evaporation and associated soil drying. Exposure of crops and forests to warmer and drier environments will increase leaf:air water vapour-pressure deficits (VPD), and will result in increased drought susceptibility and reduced productivity, not only in arid regions but also in tropical regions with seasonal dry periods. Fast-growing, short-rotation forestry (SRF) bioenergy crops such as poplar (Populus spp.) and willow (Salix spp.) are particularly susceptible to hydraulic failure following drought stress due to their isohydric nature and relatively high stomatal conductance. One approach to sustaining plant productivity is to improve water-use efficiency (WUE) by engineering crassulacean acid metabolism (CAM) into C3 crops. CAM improves WUE by shifting stomatal opening and primary CO2 uptake and fixation to the night-time when leaf:air VPD is low. CAM members of the tree genus Clusia exemplify the compatibility of CAM performance within tree species and highlight CAM as a mechanism to conserve water and maintain carbon uptake during drought conditions. The introduction of bioengineered CAM into SRF bioenergy trees is a potentially viable path to sustaining agroforestry production systems in the face of a globally changing climate. PMID:25366937

  7. Hydrologic Activity of Deciduous Agroforestry Tree : Observed through Monitoring of Stable Isotopes in Stem Water, Solar Radiation Attenuation, and Sapflow

    NASA Astrophysics Data System (ADS)

    Ceperley, N. C.; Mande, T.; Parlange, M. B.

    2012-12-01

    The net benefit of agroforestry trees for small scale farmers in dryland agricultural systems is debatable because while they provide significant direct and indirect services, they also consume considerable amounts of scare water resources. In this study we monitor the stable isotopes of water to improve a water budget of a Sclerocarya birrea tree in a millet field in South Eastern Burkina Faso. Data obtained from air temperature and humidity, surface temperature, solar radiation, and soil moisture sensors attached to a wireless sensor network uniquely configured around the agroforestry tree provided the initial calculation of the local water balance. Isotopic ratios were determined from water extracted from stems and sub canopy soil, and from nearby ground water, precipitation, and surface water that was sampled weekly. A linear mixing model is used to predict when the tree switched between water sources. The results from the linear mixing model coupled with a tree water balance demonstrate the extreme seasonality of the annual cycle of water use by this deciduous species.

  8. [Comparison of coleopteran and spider communities between a reforested area and a still steppe area in a pre-Saharan region of Algeria].

    PubMed

    Brague-Bouragba, Nadia; Brague, Ahmed; Dellouli, Saliha; Lieutier, François

    2007-12-01

    In the pre-Saharan region of Djelfa (Algeria), the coleopteran and spider communities are compared between two neighbouring ecosystems, the one kept as a steppe, the other one reforested with Aleppo pine. In three plots in each area, pitfall (Barber) traps were sampled monthly during one year and arthropods were identified and counted. Two thousand five hundred and fifty-seven individuals, distributed into 95 species, were collected, belonging to four coleopteran families (Carabidae, Scarabaeidae, Tenebrionidae, and Curculionidae), and 14 spider families. The Tenebrionidae (43% of the species and 87% of the individuals) were clearly the most represented group of insects, numerically because of the considerable abundance of Pimelia mauritanica in the reforested area, where this species accounted for half the total number of catches. Among the spiders, the Gnaphosidae represented 40% of the individuals and one-third of the species. The total species richness of the two areas was the same, but, considering the total number of collected species, individual abundance and diversity indexes (Shannon, Simpson) were lower in the reforested zone. However, these parameters became fully comparable when excluding P. mauritanica from the calculations. Without P. mauritanica, numbers and species richness of Tenebrionidae were similar in both areas. Curculionidae had higher populations and higher species diversity in the steppe area, while Scarabeidae were equally abundant in the two ecosystems types. The number, the species richness, and the diversity indexes of Carabidae were much lower in the reforested area than in the steppe one. The opposite was observed with spiders. Nevertheless, more or less important variations in the number of individuals, in one or another direction depending on the species, existed among each taxonomic group. It is concluded that reforestation has not changed biological diversity, but has induced dramatic modifications in the organisation and

  9. How To Assess The Future Tree-Cover Potential For Reforestation Planning In Semi-Arid Regions? An Attempt Using The Vegetation Model ORCHIDEE

    NASA Astrophysics Data System (ADS)

    Rajaud, A.; De Noblet-Ducoudré, N.

    2015-12-01

    More and more reforestation projects are undertaken at local to continental scales to fight desertification, to address development challenges, and to improve local living conditions in tropical semi-arid regions. These regions are very sensitive to climatic changes and the potential for maintaining tree-covers will be altered in the next decades. Therefore, reforestation planning needs predicting the future "climatic tree-cover potential": the optimum tree-fraction sustainable in future climatic states. Global circulation models projections provide possible future climatologies for the 21st century. These can be used at the global scale to force a land-surface model, which in turn simulates the vegetation development under these conditions. The tree cover leading to an optimum development may then be identified. We propose here to run a state-of-the-art model and to assess the span and the relevance of the answers that can be obtained for reforestation planning. The ORCHIDEE vegetation model is chosen here to allow a multi-criteria evaluation of the optimum cover, as it returns surface climate state variables as well as vegetation functioning and biomass products. It is forced with global climate data (WFDEI and CRU) for the 20th century and models projections (CMIP5 outputs) for the 21st century. At the grid-cell resolution of the forcing climate data, tree-covers ranging from 0 to 100% are successively prescribed. A set of indicators is then derived from the model outputs, meant for modulating reforestation strategies according to the regional priorities (e.g. maximize the biomass production or decrease the surface air temperature). The choice of indicators and the relevance of the final answers provided will be collectively assessed by the climate scientists and reforestation project management experts from the KINOME social enterprise (http://en.kinome.fr). Such feedback will point towards the model most urging needs for improvement.

  10. Changes in soil physical and chemical properties in long term improved natural and traditional agroforestry management systems of cacao genotypes in Peruvian Amazon.

    PubMed

    Arévalo-Gardini, Enrique; Canto, Manuel; Alegre, Julio; Loli, Oscar; Julca, Alberto; Baligar, Virupax

    2015-01-01

    Growing cacao (Theobroma cacao L.) in an agroforestry system generates a productive use of the land, preserves the best conditions for physical, chemical and biological properties of tropical soils, and plays an important role in improving cacao production and fertility of degraded tropical soils. The aim of this study was to evaluate the impact of two long term agroforestry systems of cacao management on soil physical and chemical properties in an area originally inhabited by 30 years old native secondary forest (SF). The two agroforestry systems adapted were: improved natural agroforestry system (INAS) where trees without economic value were selectively removed to provide 50% shade and improved traditional agroforestry system (ITAS) where all native trees were cut and burnt in the location. For evaluation of the changes of soil physical and chemical properties with time due to the imposed cacao management systems, plots of 10 cacao genotypes (ICS95, UF613, CCN51, ICT1112, ICT1026, ICT2162, ICT2171, ICT2142, H35, U30) and one plot with a spontaneous hybrid were selected. Soil samples were taken at 0-20, 20-40 and 40-60 cm depths before the installation of the management systems (2004), and then followed at two years intervals. Bulk density, porosity, field capacity and wilting point varied significantly during the years of assessment in the different soil depths and under the systems assessed. Soil pH, CEC, exchangeable Mg and sum of the bases were higher in the INAS than the ITAS. In both systems, SOM, Ext. P, K and Fe, exch. K, Mg and Al+H decreased with years of cultivation; these changes were more evident in the 0-20 cm soil depth. Overall improvement of SOM and soil nutrient status was much higher in the ITAS than INAS. The levels of physical and chemical properties of soil under cacao genotypes showed a marked difference in both systems. PMID:26181053

  11. Changes in Soil Physical and Chemical Properties in Long Term Improved Natural and Traditional Agroforestry Management Systems of Cacao Genotypes in Peruvian Amazon

    PubMed Central

    Arévalo-Gardini, Enrique; Canto, Manuel; Alegre, Julio; Loli, Oscar; Julca, Alberto; Baligar, Virupax

    2015-01-01

    Growing cacao (Theobroma cacao L.) in an agroforestry system generates a productive use of the land, preserves the best conditions for physical, chemical and biological properties of tropical soils, and plays an important role in improving cacao production and fertility of degraded tropical soils. The aim of this study was to evaluate the impact of two long term agroforestry systems of cacao management on soil physical and chemical properties in an area originally inhabited by 30 years old native secondary forest (SF). The two agroforestry systems adapted were: improved natural agroforestry system (INAS) where trees without economic value were selectively removed to provide 50% shade and improved traditional agroforestry system (ITAS) where all native trees were cut and burnt in the location. For evaluation of the changes of soil physical and chemical properties with time due to the imposed cacao management systems, plots of 10 cacao genotypes (ICS95, UF613, CCN51, ICT1112, ICT1026, ICT2162, ICT2171, ICT2142, H35, U30) and one plot with a spontaneous hybrid were selected. Soil samples were taken at 0-20, 20-40 and 40-60 cm depths before the installation of the management systems (2004), and then followed at two years intervals. Bulk density, porosity, field capacity and wilting point varied significantly during the years of assessment in the different soil depths and under the systems assessed. Soil pH, CEC, exchangeable Mg and sum of the bases were higher in the INAS than the ITAS. In both systems, SOM, Ext. P, K and Fe, exch. K, Mg and Al+H decreased with years of cultivation; these changes were more evident in the 0-20 cm soil depth. Overall improvement of SOM and soil nutrient status was much higher in the ITAS than INAS. The levels of physical and chemical properties of soil under cacao genotypes showed a marked difference in both systems. PMID:26181053

  12. The effect of mangrove reforestation on the accumulation of PCBs in sediment from different habitats in Guangdong, China.

    PubMed

    Zhao, Bo; Zhou, Yan-Wu; Chen, Gui-Zhu

    2012-08-01

    To investigate the influence of mangrove reforestation on the accumulation of PCBs, the concentrations and homologue patterns of polychlorinated biphenyls in surface sediments from different mangrove forests and their adjacent mud flats in Guangdong Province were determined. The total PCB concentrations in the sediments ranged from 3.03 to 46.62 ng g⁻¹ (dry weight). Differences in the accumulation and distribution of PCBs were found between the mangrove sites and the mud flats. Furthermore, the natural forests and restored mangrove forests of native species showed slight PCB contamination, whereas the exotic species Sonneratia apetala exacerbated the PCB pollution at certain sites. It was suggested that the native mangrove species Kandelia candel and Aegiceras corniculatum could represent good choices for the phytoremediation of PCB contamination. PMID:22704149

  13. Appropriate technology sourcebook. Volume II

    SciTech Connect

    Darrow, K.; Keller, K.; Pam, R

    1981-01-01

    The second in a 2 volume set of guides to practical books and plans for village and small community technology, with over 500 annotated references in print in 1980/1. The forestry section includes material on deforestation, conservation, reforestation, firewood crops, agroforestry, timber drying and the safe use of chain saws. Improved cooking stoves and charcoal kilns are covered in another section, and there is also a section on aquaculture. A glossary and a general index are included.

  14. Assessment of Agroforestry Trees in Dry-land Savanna Supports Ecohydrologic Separation

    NASA Astrophysics Data System (ADS)

    Ceperley, Natalie; Mande, Theophile; Van de Giesen, Nick; Tyler, Scott; Parlange, Marc

    2016-04-01

    We use stable isotopes of water to demonstrate the ecohydrologic separation, or the plant controlled compartmentalization, of different water sources in a catchment in South Eastern Burkina Faso. We analyze water extracted from the groundwater, stream water, precipitation, perched aquifer, xylem water of agroforestry trees, and sub-canopy soil water over a 6 year period to explore how the separation affects different components of the system over time. The ratio between deuterium and O18 allows us to assess whether the water that plants use is the same as the water that recharges the aquifer and runs off in the stream. Water extracted from the tree at leaf out in February corresponded to deuterium and O18 concentrations of the groundwater, a drop from its dry season, enriched, levels which mimicked the soil water. Examination of the isotopic signature suggests that the size of tree plays an important role in duration and timing of this leaf-out as well as the degree of enrichment during the peak of the dry season. Dates of leaf out were confirmed by analyzing sub-canopy radiation and photographs. Water extracted from roots suggests that the trees are performing hydraulic redistribution, or lifting the ground water and 'sharing it' with the rooting zone soil during the dry season. The enriched level of xylem, in this case, is a product of water loss and enrichment along the travel path of the water from the roots to the tip of the branch, as evidenced by the variation according to size of tree. Vapor pressure deficit, sap flow, soil water, and soil moisture interactions support this picture of interacting controls, separate from hydrologic triggers on the water movement in the tree. A second round of sampling focused on the leaf out period by extracting and analyzing stem water from throughout the canopy during the leaf out. Simultaneous large eddy correlation revealed high levels of latent energy flux, even during the dry season. Our isotope analysis allowed us to

  15. The Network Of Shelterbelts As An Agroforestry System Controlling The Water Resources And Biodiversity In The Agricultural Landscape

    NASA Astrophysics Data System (ADS)

    Kędziora, Andrzej

    2015-01-01

    Long-term human activity has led to many unfavourable changes in landscape structure. The main negative effect has been a simplification of landscape structure reflecting the removal of stable ecosystems, such as forests, shelterbelts, strips of meadows and so on, which were converted into unstable ecosystems, mainly farmlands. Thanks to these changes, serious threats have been posed to the sustainable development of rural areas. The most hazardous of these involve a deteriorating of water balance, increased surface and ground water pollution, and impoverishment of biodiversity. An agroforestry system can serve as a toolkit which allows counteracting such negative changes in the landscape. This paper presents the main findings emerge from long-term investigations on the above issues carried out by the Institute for the Agricultural and Forest Environment of the Polish Academy of Sciences.

  16. Spatial and temporal effects of drought on soil CO2 efflux in a cacao agroforestry system in Sulawesi, Indonesia

    NASA Astrophysics Data System (ADS)

    van Straaten, O.; Veldkamp, E.; Köhler, M.; Anas, I.

    2010-04-01

    Climate change induced droughts pose a serious threat to ecosystems across the tropics and sub-tropics, particularly to those areas not adapted to natural dry periods. In order to study the vulnerability of cacao (Theobroma cacao) - Gliricidia sepium agroforestry plantations to droughts a large scale throughfall displacement roof was built in Central Sulawesi, Indonesia. In this 19-month experiment, we compared soil surface CO2 efflux (soil respiration) from three roof plots with three adjacent control plots. Soil respiration rates peaked at intermediate soil moisture conditions and decreased under increasingly dry conditions (drought induced), or increasingly wet conditions (as evidenced in control plots). The roof plots exhibited a slight decrease in soil respiration compared to the control plots (average 13% decrease). The strength of the drought effect was spatially variable - while some measurement chamber sites reacted strongly (responsive) to the decrease in soil water content (up to R2=0.70) (n=11), others did not react at all (non-responsive) (n=7). A significant correlation was measured between responsive soil respiration chamber sites and sap flux density ratios of cacao (R=0.61) and Gliricidia (R=0.65). Leaf litter CO2 respiration decreased as conditions became drier. The litter layer contributed approximately 3-4% of the total CO2 efflux during dry periods and up to 40% during wet periods. Within days of roof opening soil CO2 efflux rose to control plot levels. Thereafter, CO2 efflux remained comparable between roof and control plots. The cumulative effect on soil CO2 emissions over the duration of the experiment was not significantly different: the control plots respired 11.1±0.5 Mg C ha-1 yr-1, while roof plots respired 10.5±0.5 Mg C ha-1 yr-1. The relatively mild decrease measured in soil CO2 efflux indicates that this agroforestry ecosystem is capable of mitigating droughts with only minor stress symptoms.

  17. Contemporary Subsoil Carbon Accumulation During Reforestation is Conditioned by Long-term, Coupled C-Fe Cycling in Upland Soils

    NASA Astrophysics Data System (ADS)

    Bacon, A. R.; Richter, D., Jr.; Heckman, K. A.; Veverica, T. J.; Nave, L. E.

    2014-12-01

    To understand deep soil carbon stabilization and change during reforestation we sampled bulk subsoils and individual redoximorphic features from a network of two meter deep soil pits along a gentle catena (3% slope) in the Southern Piedmont of North Carolina, USA. Until 1910, the catena was under cultivation. Since then, half of the soils we excavated have supported deeply rooted pine forests while the other half have continued to support relatively shallow rooted grasses and forbs. Across the catena, accordant with the divergent rooting regimes, subsoil roots were three times more abundant under forest than grass, and Δ14C in bulk subsoil samples was enriched by an average of 123‰ under forest relative to grass (p=0.0267). Bulk subsoils, however, were extremely heterogeneous and contained three well-defined redoximorphic feature microsites. Over the lifetime of these upland soils, coupled carbon-iron cycling during transient oxygen limitation created the microsites and thereby imparted subsoils with steep biogeochemical gradients millimeters to centimeters apart. Concentration of operationally defined crystalline iron-oxyhydroxides was on average ten times higher in Fe-enriched microsites (30.1 ± 2.5 mg/g, mean ± 1 SE) than Fe-depleted microsites (2.9 ± 0.3 mg/g) and gley microsites (3.3 ± 0.4 mg/g) across the catena. Under the deeply rooted forest Δ14C in gley microsites and Fe-depleted microsites was enriched by an average of 73‰ (p=0.0194) and 94‰ (p=0.0416), respectively relative to the same microsites under grass. Meanwhile, Δ14C in Fe-enriched microsites was unchanged by the divergent rooting regimes (p=0.1936). These microsite dependent patterns of radiocarbon enrichment indicate that subsoil C stabilization during reforestation of the catena was spatially conditioned by historic coupled carbon-iron cycling. We detail the mechanisms of this conditioning, and argue that similar long-term biogeochemical processes influence contemporary subsoil C

  18. Reforestation Sites Show Similar and Nested AMF Communities to an Adjacent Pristine Forest in a Tropical Mountain Area of South Ecuador

    PubMed Central

    Haug, Ingeborg; Setaro, Sabrina; Suárez, Juan Pablo

    2013-01-01

    Arbuscular mycorrhizae are important for growth and survival of tropical trees. We studied the community of arbuscular mycorrhizal fungi in a tropical mountain rain forest and in neighbouring reforestation plots in the area of Reserva Biológica San Francisco (South Ecuador). The arbuscular mycorrhizal fungi were analysed with molecular methods sequencing part of the 18 S rDNA. The sequences were classified as Operational Taxonomic Units (OTUs). We found high fungal species richness with OTUs belonging to Glomerales, Diversisporales and Archaeosporales. Despite intensive sampling, the rarefaction curves are still unsaturated for the pristine forest and the reforestation plots. The communities consisted of few frequent and many rare species. No specific interactions are recognizable. The plant individuals are associated with one to ten arbuscular mycorrhizal fungi and mostly with one to four. The fungal compositions associated with single plant individuals show a great variability and variety within one plant species. Planted and naturally occurring plants show high similarities in their fungal communities. Pristine forest and reforestation plots showed similar richness, similar diversity and a significantly nested structure of plant-AMF community. The results indicate that small-scale fragmentation presently found in this area has not destroyed the natural AMF community, at least yet. Thus, the regeneration potential of natural forest vegetation at the tested sites is not inhibited by a lack of appropriate mycobionts. PMID:23671682

  19. Reforestation sites show similar and nested AMF communities to an adjacent pristine forest in a tropical mountain area of South Ecuador.

    PubMed

    Haug, Ingeborg; Setaro, Sabrina; Suárez, Juan Pablo

    2013-01-01

    Arbuscular mycorrhizae are important for growth and survival of tropical trees. We studied the community of arbuscular mycorrhizal fungi in a tropical mountain rain forest and in neighbouring reforestation plots in the area of Reserva Biológica San Francisco (South Ecuador). The arbuscular mycorrhizal fungi were analysed with molecular methods sequencing part of the 18 S rDNA. The sequences were classified as Operational Taxonomic Units (OTUs). We found high fungal species richness with OTUs belonging to Glomerales, Diversisporales and Archaeosporales. Despite intensive sampling, the rarefaction curves are still unsaturated for the pristine forest and the reforestation plots. The communities consisted of few frequent and many rare species. No specific interactions are recognizable. The plant individuals are associated with one to ten arbuscular mycorrhizal fungi and mostly with one to four. The fungal compositions associated with single plant individuals show a great variability and variety within one plant species. Planted and naturally occurring plants show high similarities in their fungal communities. Pristine forest and reforestation plots showed similar richness, similar diversity and a significantly nested structure of plant-AMF community. The results indicate that small-scale fragmentation presently found in this area has not destroyed the natural AMF community, at least yet. Thus, the regeneration potential of natural forest vegetation at the tested sites is not inhibited by a lack of appropriate mycobionts. PMID:23671682

  20. Knowledge and valuation of Andean agroforestry species: the role of sex, age, and migration among members of a rural community in Bolivia

    PubMed Central

    2013-01-01

    Background Agroforestry is a sustainable land use method with a long tradition in the Bolivian Andes. A better understanding of people’s knowledge and valuation of woody species can help to adjust actor-oriented agroforestry systems. In this case study, carried out in a peasant community of the Bolivian Andes, we aimed at calculating the cultural importance of selected agroforestry species, and at analysing the intracultural variation in the cultural importance and knowledge of plants according to peasants’ sex, age, and migration. Methods Data collection was based on semi-structured interviews and freelisting exercises. Two ethnobotanical indices (Composite Salience, Cultural Importance) were used for calculating the cultural importance of plants. Intracultural variation in the cultural importance and knowledge of plants was detected by using linear and generalised linear (mixed) models. Results and discussion The culturally most important woody species were mainly trees and exotic species (e.g. Schinus molle, Prosopis laevigata, Eucalyptus globulus). We found that knowledge and valuation of plants increased with age but that they were lower for migrants; sex, by contrast, played a minor role. The age effects possibly result from decreasing ecological apparency of valuable native species, and their substitution by exotic marketable trees, loss of traditional plant uses or the use of other materials (e.g. plastic) instead of wood. Decreasing dedication to traditional farming may have led to successive abandonment of traditional tool uses, and the overall transformation of woody plant use is possibly related to diminishing medicinal knowledge. Conclusions Age and migration affect how people value woody species and what they know about their uses. For this reason, we recommend paying particular attention to the potential of native species, which could open promising perspectives especially for the young migrating peasant generation and draw their interest in

  1. Impacts of reforestation approaches on runoff control in the hilly red soil region of Southern China

    NASA Astrophysics Data System (ADS)

    Zheng, Hua; Chen, Falin; Ouyang, Zhiyun; Tu, Naimei; Xu, Weihua; Wang, Xiaoke; Miao, Hong; Li, Xiquan; Tian, Yuxin

    2008-07-01

    SummaryVegetation structure and soil properties are not only correlated with forest management practices, but also affect soil and water loss significantly. To estimate the long-term influences of regenerating forest cover on soil and water loss from degraded land, the runoff and soil loss in the context of different forest restoration approaches, including a control plot (CL) and plantations of slash pine (Pinus elliottii), Chinese fir (Cunninghamia lanceolata), tea-oil camellia (Camellia oleifera), and natural secondary forest, were monitored in runoff plots over a 4-year period (2000-2003) in a hilly red soil region in Southern China. Relevant ecological factors and management intensity, were also measured. The results indicated that the four forest restoration approaches decreased surface runoff by 63.0-88.1% and soil erosion by 75.5-97.1% compared to the control. Moreover, runoff and soil erosion in tea-camellia plantation (TCP) and natural secondary forest (NSF) plots were significantly lower than with other treatments. Canopy cover, litter fall, plant roots, plant life forms, soil properties, and vegetation structure are important ecological factors that determine the magnitude of soil loss. Vegetation structure and plant life forms are the main factors reducing surface runoff and the movement of sediments. Effective control of soil and water loss in NSF and TCP are closely related to multiply stratified communities and the presence of specific plant life forms (the herbaceous keystone species Dicranopteris linearis), respectively. In addition, the above mentioned factors were sensitive to forest management patterns, including improper mechanical cultivation. Management practices should attempt to minimize disturbances to these factors to control runoff and soil erosion in each forest management unit. In particular, mechanical cultivation should loosen the soil around the base of a tree only, instead of over the entire ground surface, in the early stages of

  2. FOREST MANAGEMENT AND AGROFORESTRY TO SEQUESTER AND CONSERVE ATMOSPHERIC CARBON DIOXIDE

    EPA Science Inventory

    Overall, the biological opportunity to conserve and sequester carbon in the terrestrial biosphere, especially in forest systems, appears significant. ith careful planning and implementation, management practices useful for this carbon benefit would appear to have potential to pro...

  3. Global Tree Cover and Biomass Carbon on Agricultural Land: The contribution of agroforestry to global and national carbon budgets.

    PubMed

    Zomer, Robert J; Neufeldt, Henry; Xu, Jianchu; Ahrends, Antje; Bossio, Deborah; Trabucco, Antonio; van Noordwijk, Meine; Wang, Mingcheng

    2016-01-01

    Agroforestry systems and tree cover on agricultural land make an important contribution to climate change mitigation, but are not systematically accounted for in either global carbon budgets or national carbon accounting. This paper assesses the role of trees on agricultural land and their significance for carbon sequestration at a global level, along with recent change trends. Remote sensing data show that in 2010, 43% of all agricultural land globally had at least 10% tree cover and that this has increased by 2% over the previous ten years. Combining geographically and bioclimatically stratified Intergovernmental Panel on Climate Change (IPCC) Tier 1 default estimates of carbon storage with this tree cover analysis, we estimated 45.3 PgC on agricultural land globally, with trees contributing >75%. Between 2000 and 2010 tree cover increased by 3.7%, resulting in an increase of >2 PgC (or 4.6%) of biomass carbon. On average, globally, biomass carbon increased from 20.4 to 21.4 tC ha(-1). Regional and country-level variation in stocks and trends were mapped and tabulated globally, and for all countries. Brazil, Indonesia, China and India had the largest increases in biomass carbon stored on agricultural land, while Argentina, Myanmar, and Sierra Leone had the largest decreases. PMID:27435095

  4. Global Tree Cover and Biomass Carbon on Agricultural Land: The contribution of agroforestry to global and national carbon budgets

    NASA Astrophysics Data System (ADS)

    Zomer, Robert J.; Neufeldt, Henry; Xu, Jianchu; Ahrends, Antje; Bossio, Deborah; Trabucco, Antonio; van Noordwijk, Meine; Wang, Mingcheng

    2016-07-01

    Agroforestry systems and tree cover on agricultural land make an important contribution to climate change mitigation, but are not systematically accounted for in either global carbon budgets or national carbon accounting. This paper assesses the role of trees on agricultural land and their significance for carbon sequestration at a global level, along with recent change trends. Remote sensing data show that in 2010, 43% of all agricultural land globally had at least 10% tree cover and that this has increased by 2% over the previous ten years. Combining geographically and bioclimatically stratified Intergovernmental Panel on Climate Change (IPCC) Tier 1 default estimates of carbon storage with this tree cover analysis, we estimated 45.3 PgC on agricultural land globally, with trees contributing >75%. Between 2000 and 2010 tree cover increased by 3.7%, resulting in an increase of >2 PgC (or 4.6%) of biomass carbon. On average, globally, biomass carbon increased from 20.4 to 21.4 tC ha‑1. Regional and country-level variation in stocks and trends were mapped and tabulated globally, and for all countries. Brazil, Indonesia, China and India had the largest increases in biomass carbon stored on agricultural land, while Argentina, Myanmar, and Sierra Leone had the largest decreases.

  5. [Temporal and spatial distribution of ants in a light gradient, in a coffee agroforestry system, Turrialba, Costa Rica].

    PubMed

    Varón, Edgar H; Hanson, Paul; Longino, John T; Borbón, Olger; Carballo, Manuel; Hilje, Luko

    2007-01-01

    Shade trees are frequently present in coffee (Coffea arabica L.) agroforestry systems of Mesoamerica. These systems can harbor a rich entomofauna, including ants, which could be predators of key pests in these systems. However, the role of shade on the distribution and abundance of these ants is unknown, yet such knowledge could suggest guidelines for manipulating certain environmental conditions of their habitat, thereby achieving their conservation and increase. Therefore, we studied the effect of shade on the spatial and temporal distribution of three ant species (Solenopsis geminata, Pheidole radoszkowskii and Crematogaster curvispinosa) that may prey on the coffee berry borer, Hypothenemus hampei (Coleoptera: Scolytidae), and the mahogany shootborer, Hypsipyla grandella (Lepidoptera: Pyralidae). To do this, abundance was evaluated across a sun-shade gradient in a coffee plantation with four alternate plots (from pure sun to total shade) in Turrialba, Costa Rica. In the community that was studied 28 species of ants were collected, of which S. geminata was the dominant species (79% of the total individuals), followed by P. radoszkowskii (16 %). S. geminata and C. curvispinosa preferred sunny areas, while P. radoszkowskii showed no defined preference. Likewise, with respect to location, S. geminata predominated in the soil, while P. radoszkowskii and C. curvispinosa predominated in coffee bushes. PMID:19086397

  6. The effect of trees on preferential flow and soil infiltrability in an agroforestry parkland in semiarid Burkina Faso

    NASA Astrophysics Data System (ADS)

    Bargués Tobella, A.; Reese, H.; Almaw, A.; Bayala, J.; Malmer, A.; Laudon, H.; Ilstedt, U.

    2014-04-01

    Water scarcity constrains the livelihoods of millions of people in tropical drylands. Tree planting in these environments is generally discouraged due to the large water consumption by trees, but this view may neglect their potential positive impacts on water availability. The effect of trees on soil hydraulic properties linked to groundwater recharge is poorly understood. In this study, we performed 18 rainfall simulations and tracer experiments in an agroforestry parkland in Burkina Faso to investigate the effect of trees and associated termite mounds on soil infiltrability and preferential flow. The sampling points were distributed in transects each consisting of three positions: (i) under a single tree, (ii) in the middle of an open area, and (iii) under a tree associated with a termite mound. The degree of preferential flow was quantified through parameters based on the dye infiltration patterns, which were analyzed using image analysis of photographs. Our results show that the degree of preferential flow was highest under trees associated with termite mounds, intermediate under single trees, and minimal in the open areas. Tree density also had an influence on the degree of preferential flow, with small open areas having more preferential flow than large ones. Soil infiltrability was higher under single trees than in the open areas or under trees associated with a termite mound. The findings from this study demonstrate that trees have a positive impact on soil hydraulic properties influencing groundwater recharge, and thus such effects must be considered when evaluating the impact of trees on water resources in drylands.

  7. Global Tree Cover and Biomass Carbon on Agricultural Land: The contribution of agroforestry to global and national carbon budgets

    PubMed Central

    Zomer, Robert J.; Neufeldt, Henry; Xu, Jianchu; Ahrends, Antje; Bossio, Deborah; Trabucco, Antonio; van Noordwijk, Meine; Wang, Mingcheng

    2016-01-01

    Agroforestry systems and tree cover on agricultural land make an important contribution to climate change mitigation, but are not systematically accounted for in either global carbon budgets or national carbon accounting. This paper assesses the role of trees on agricultural land and their significance for carbon sequestration at a global level, along with recent change trends. Remote sensing data show that in 2010, 43% of all agricultural land globally had at least 10% tree cover and that this has increased by 2% over the previous ten years. Combining geographically and bioclimatically stratified Intergovernmental Panel on Climate Change (IPCC) Tier 1 default estimates of carbon storage with this tree cover analysis, we estimated 45.3 PgC on agricultural land globally, with trees contributing >75%. Between 2000 and 2010 tree cover increased by 3.7%, resulting in an increase of >2 PgC (or 4.6%) of biomass carbon. On average, globally, biomass carbon increased from 20.4 to 21.4 tC ha−1. Regional and country-level variation in stocks and trends were mapped and tabulated globally, and for all countries. Brazil, Indonesia, China and India had the largest increases in biomass carbon stored on agricultural land, while Argentina, Myanmar, and Sierra Leone had the largest decreases. PMID:27435095

  8. Land cover changes and forest landscape evolution (1985-2009) in a typical Mediterranean agroforestry system (High Agri Valley)

    NASA Astrophysics Data System (ADS)

    Simoniello, T.; Coluzzi, R.; Imbrenda, V.; Lanfredi, M.

    2014-08-01

    The present study focuses on the transformations of a typical Mediterranean agroforestry landscape of southern Italy (High Agri Valley - Basilicata region) occurred during 24 years. In this period, the valuable agricultural and natural areas that compose such a landscape were subjected to intensive industry-related activities linked to the exploitation of the largest European on-shore oil reservoir. Landsat imagery acquired in 1985 and 2009 were used to detect changes in forest areas and major land use trajectories. Landscape metrics indicators were adopted to characterize landscape structure and evolution of both the complex ecomosaic (14 land cover classes) and the Forest/Non Forest arrangement. Our results indicate a net increase of 11% of forest areas between 1985 and 2009. The major changes concern: increase of all forest covers at the expense of pastures and grasses, enlargement of riparian vegetation, expansion of artificial areas. The observed expansion of forests was accompanied by a decrease of the fragmentation levels likely due to the reduction of small glades that break forest homogeneity and to the recolonization of herbaceous areas. Overall, we observe an evolution towards a more stable configuration depicting a satisfactory picture of vegetation health.

  9. Land cover changes and forest landscape evolution (1985-2009) in a typical Mediterranean agroforestry system (high Agri Valley)

    NASA Astrophysics Data System (ADS)

    Simoniello, T.; Coluzzi, R.; Imbrenda, V.; Lanfredi, M.

    2015-06-01

    The present study focuses on the transformations of a typical Mediterranean agroforestry landscape of southern Italy (high Agri Valley - Basilicata region) that occurred over 24 years. In this period, the valuable agricultural and natural areas that compose such a landscape were subjected to intensive industry-related activities linked to the exploitation of the largest European onshore oil reservoir. Landsat imagery acquired in 1985 and 2009 were used to detect changes in forest areas and major land use trajectories. Landscape metrics indicators were adopted to characterize landscape structure and evolution of both the complex ecomosaic (14 land cover classes) and the forest/non-forest arrangement. Our results indicate a net increase of 11% of forest areas between 1985 and 2009. The major changes concern increase of all forest covers at the expense of pastures and grasses, enlargement of riparian vegetation, and expansion of artificial areas. The observed expansion of forests was accompanied by a decrease of the fragmentation levels likely due to the reduction of small glades that break forest homogeneity and to the recolonization of herbaceous areas. Overall, we observe an evolution towards a more stable configuration depicting a satisfactory picture of vegetation health.

  10. "Landslide at sunuapa 401 (hydrocarbon exploration well). Risk reduction by mitigation measures: drainage, piles barrier and anchorages system, shotcrete and reforestation, Chiapas, México".

    NASA Astrophysics Data System (ADS)

    Cuanalo, Oscar; Polanco, Gabriel; Rivera, Julio

    2013-04-01

    We report the case of a landslide of hydrocarbon exploration well "Sunuapa 401" located in Chiapas, Mexico. First were identified the determinants and triggers factors (morphology, geology, rain, seismic and volcanic activity, human activity, etc); second we assessed the threat, vulnerability and risk from geotechnical stability analysis (safety factor and critical failure surface); third, by using the methodology of valuation factors, stabilization processes were selected and designed, and finally they were built by Petróleos Mexicanos, in order to avoid a disaster (environmental, ecological and social). These construction processes included drainage elements, flattening and benching of slopes, piles barrier and anchors, shotcrete and reforestation.

  11. Patterns in hydraulic architecture from roots to branches in six tropical tree species from cacao agroforestry and their relation to wood density and stem growth

    PubMed Central

    Kotowska, Martyna M.; Hertel, Dietrich; Rajab, Yasmin Abou; Barus, Henry; Schuldt, Bernhard

    2015-01-01

    For decades it has been assumed that the largest vessels are generally found in roots and that vessel size and corresponding sapwood area-specific hydraulic conductivity are acropetally decreasing toward the distal twigs. However, recent studies from the perhumid tropics revealed a hump-shaped vessel size distribution. Worldwide tropical perhumid forests are extensively replaced by agroforestry systems often using introduced species of various biogeographical and climatic origins. Nonetheless, it is unknown so far what kind of hydraulic architectural patterns are developed in those agroforestry tree species and which impact this exerts regarding important tree functional traits, such as stem growth, hydraulic efficiency and wood density (WD). We investigated wood anatomical and hydraulic properties of the root, stem and branch wood in Theobroma cacao and five common shade tree species in agroforestry systems on Sulawesi (Indonesia); three of these were strictly perhumid tree species, and the other three tree species are tolerating seasonal drought. The overall goal of our study was to relate these properties to stem growth and other tree functional traits such as foliar nitrogen content and sapwood to leaf area ratio. Our results confirmed a hump-shaped vessel size distribution in nearly all species. Drought-adapted species showed divergent patterns of hydraulic conductivity, vessel density, and relative vessel lumen area between root, stem and branch wood compared to wet forest species. Confirming findings from natural old-growth forests in the same region, WD showed no relationship to specific conductivity. Overall, aboveground growth performance was better predicted by specific hydraulic conductivity than by foliar traits and WD. Our study results suggest that future research on conceptual trade-offs of tree hydraulic architecture should consider biogeographical patterns underlining the importance of anatomical adaptation mechanisms to environment. PMID:25873922

  12. Patterns in hydraulic architecture from roots to branches in six tropical tree species from cacao agroforestry and their relation to wood density and stem growth.

    PubMed

    Kotowska, Martyna M; Hertel, Dietrich; Rajab, Yasmin Abou; Barus, Henry; Schuldt, Bernhard

    2015-01-01

    For decades it has been assumed that the largest vessels are generally found in roots and that vessel size and corresponding sapwood area-specific hydraulic conductivity are acropetally decreasing toward the distal twigs. However, recent studies from the perhumid tropics revealed a hump-shaped vessel size distribution. Worldwide tropical perhumid forests are extensively replaced by agroforestry systems often using introduced species of various biogeographical and climatic origins. Nonetheless, it is unknown so far what kind of hydraulic architectural patterns are developed in those agroforestry tree species and which impact this exerts regarding important tree functional traits, such as stem growth, hydraulic efficiency and wood density (WD). We investigated wood anatomical and hydraulic properties of the root, stem and branch wood in Theobroma cacao and five common shade tree species in agroforestry systems on Sulawesi (Indonesia); three of these were strictly perhumid tree species, and the other three tree species are tolerating seasonal drought. The overall goal of our study was to relate these properties to stem growth and other tree functional traits such as foliar nitrogen content and sapwood to leaf area ratio. Our results confirmed a hump-shaped vessel size distribution in nearly all species. Drought-adapted species showed divergent patterns of hydraulic conductivity, vessel density, and relative vessel lumen area between root, stem and branch wood compared to wet forest species. Confirming findings from natural old-growth forests in the same region, WD showed no relationship to specific conductivity. Overall, aboveground growth performance was better predicted by specific hydraulic conductivity than by foliar traits and WD. Our study results suggest that future research on conceptual trade-offs of tree hydraulic architecture should consider biogeographical patterns underlining the importance of anatomical adaptation mechanisms to environment. PMID:25873922

  13. Soil quality parameters for row-crop and grazed pasture systems with agroforestry buffers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Incorporation of trees and establishment of buffers are practices that can improve soil quality. Soil enzyme activities and water stable aggregates are sensitive indices for assessing soil quality by detecting early changes in soil management. However, studies comparing grazed pasture and row crop...

  14. Soil quality indicator responses to row crop, grazed pasture, and agroforestry buffer management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Incorporation of trees and establishment of grass buffers within agroecosystems are management practices shown to enhance soil quality. Soil enzyme activities and water stable aggregates (WSA) have been identified as sensitive soil quality indicators to evaluate early responses to soil management. ...

  15. Fuelwood, agro-forestry, and natural resource management: the development significance of land tenure and other resource management/utilization systems

    SciTech Connect

    Brokensha, D.; Castro, A.P.; Kundu, M.; Hewlett, B.

    1984-04-01

    Using a systems approach and focusing on the social context, the study examines natural resource management in relation to fuelwood production and agroforestry. An initial section describing the use and interlinkage of the concepts of ecozone and ecosystem is followed by a discussion of problem ecozones, human use of ecozones, agricultural ecosystems, resource competition, uses of trees and forest products, and tree planting. Rural resource management strategies at the household, community, local, and state levels are discussed in the context of political economy, land tenure and rights, tenancy and sharecropping, group or public landholding, and acquisition and transfer of land.

  16. Potential Impact of Land Use Change on Future Regional Climate in the Southeastern U.S.: Reforestation and Crop Land Conversion

    NASA Technical Reports Server (NTRS)

    Trail, M.; Tsimpidi, A. P.; Liu, P.; Tsigaridis, Konstantinos; Hu, Y.; Nenes, A.; Stone, B.; Russell, A. G.

    2013-01-01

    The impact of future land use and land cover changes (LULCC) on regional and global climate is one of the most challenging aspects of understanding anthropogenic climate change. We study the impacts of LULCC on regional climate in the southeastern U.S. by downscaling the NASA Goddard Institute for Space Studies global climate model E to the regional scale using a spectral nudging technique with the Weather Research and Forecasting Model. Climate-relevant meteorological fields are compared for two southeastern U.S. LULCC scenarios to the current land use/cover for four seasons of the year 2050. In this work it is shown that reforestation of cropland in the southeastern U.S. tends to warm surface air by up to 0.5 K, while replacing forested land with cropland tends to cool the surface air by 0.5 K. Processes leading to this response are investigated and sensitivity analyses conducted. The sensitivity analysis shows that results are most sensitive to changes in albedo and the stomatal resistance. Evaporative cooling of croplands also plays an important role in regional climate. Implications of LULCC on air quality are discussed. Summertime warming associated with reforestation of croplands could increase the production of some secondary pollutants, while a higher boundary layer will decrease pollutant concentrations; wintertime warming may decrease emissions from biomass burning from wood stoves

  17. The effect of trees on preferential flow and soil infiltrability in an agroforestry parkland in semiarid Burkina Faso

    PubMed Central

    Bargués Tobella, A; Reese, H; Almaw, A; Bayala, J; Malmer, A; Laudon, H; Ilstedt, U

    2014-01-01

    Water scarcity constrains the livelihoods of millions of people in tropical drylands. Tree planting in these environments is generally discouraged due to the large water consumption by trees, but this view may neglect their potential positive impacts on water availability. The effect of trees on soil hydraulic properties linked to groundwater recharge is poorly understood. In this study, we performed 18 rainfall simulations and tracer experiments in an agroforestry parkland in Burkina Faso to investigate the effect of trees and associated termite mounds on soil infiltrability and preferential flow. The sampling points were distributed in transects each consisting of three positions: (i) under a single tree, (ii) in the middle of an open area, and (iii) under a tree associated with a termite mound. The degree of preferential flow was quantified through parameters based on the dye infiltration patterns, which were analyzed using image analysis of photographs. Our results show that the degree of preferential flow was highest under trees associated with termite mounds, intermediate under single trees, and minimal in the open areas. Tree density also had an influence on the degree of preferential flow, with small open areas having more preferential flow than large ones. Soil infiltrability was higher under single trees than in the open areas or under trees associated with a termite mound. The findings from this study demonstrate that trees have a positive impact on soil hydraulic properties influencing groundwater recharge, and thus such effects must be considered when evaluating the impact of trees on water resources in drylands. Key Points Trees in dryland landscapes increase soil infiltrability and preferential flow Termite mounds in association with trees further enhance preferential flow PMID:25641996

  18. Tree growth and management in Ugandan agroforestry systems: effects of root pruning on tree growth and crop yield.

    PubMed

    Wajja-Musukwe, Tellie-Nelson; Wilson, Julia; Sprent, Janet I; Ong, Chin K; Deans, J Douglas; Okorio, John

    2008-02-01

    Tree root pruning is a potential tool for managing belowground competition when trees and crops are grown together in agroforestry systems. We investigated the effects of tree root pruning on shoot growth and root distribution of Alnus acuminata (H.B. & K.), Casuarina equisetifolia L., Grevillea robusta A. Cunn. ex R. Br., Maesopsis eminii Engl. and Markhamia lutea (Benth.) K. Schum. and on yield of adjacent crops in sub-humid Uganda. The trees were 3 years old at the commencement of the study, and most species were competing strongly with crops. Tree roots were pruned 41 months after planting by cutting and back-filling a trench to a depth of 0.3 m, at a distance of 0.3 m from the trees, on one side of the tree row. The trench was reopened and roots recut at 50 and 62 months after planting. We assessed the effects on tree growth and root distribution over a 3 year period, and crop yield after the third root pruning at 62 months. Overall, root pruning had only a slight effect on aboveground tree growth: height growth was unaffected and diameter growth was reduced by only 4%. A substantial amount of root regrowth was observed by 11 months after pruning. Tree species varied in the number and distribution of roots, and C. equisetifolia and M. lutea had considerably more roots per unit of trunk volume than the other species, especially in the surface soil layers. Casuarina equisetifolia and M. eminii were the tree species most competitive with crops and G. robusta and M. lutea the least competitive. Crop yield data provided strong evidence of the redistribution of root activity following root pruning, with competition increasing on the unpruned side of tree rows. Thus, one-sided root pruning will be useful in only a few circumstances. PMID:18055434

  19. Ensemble Composition and Activity Levels of Insectivorous Bats in Response to Management Intensification in Coffee Agroforestry Systems

    PubMed Central

    Williams-Guillén, Kimberly; Perfecto, Ivette

    2011-01-01

    Shade coffee plantations have received attention for their role in biodiversity conservation. Bats are among the most diverse mammalian taxa in these systems; however, previous studies of bats in coffee plantations have focused on the largely herbivorous leaf-nosed bats (Phyllostomidae). In contrast, we have virtually no information on how ensembles of aerial insectivorous bats – nearly half the Neotropical bat species – change in response to habitat modification. To evaluate the effects of agroecosystem management on insectivorous bats, we studied their diversity and activity in southern Chiapas, Mexico, a landscape dominated by coffee agroforestry. We used acoustic monitoring and live captures to characterize the insectivorous bat ensemble in forest fragments and coffee plantations differing in the structural and taxonomic complexity of shade trees. We captured bats of 12 non-phyllostomid species; acoustic monitoring revealed the presence of at least 12 more species of aerial insectivores. Richness of forest bats was the same across all land-use types; in contrast, species richness of open-space bats increased in low shade, intensively managed coffee plantations. Conversely, only forest bats demonstrated significant differences in ensemble structure (as measured by similarity indices) across land-use types. Both overall activity and feeding activity of forest bats declined significantly with increasing management intensity, while the overall activity, but not feeding activity, of open-space bats increased. We conclude that diverse shade coffee plantations in our study area serve as valuable foraging and commuting habitat for aerial insectivorous bats, and several species also commute through or forage in low shade coffee monocultures. PMID:21298059

  20. TEK and biodiversity management in agroforestry systems of different socio-ecological contexts of the Tehuacán Valley.

    PubMed

    Vallejo-Ramos, Mariana; Moreno-Calles, Ana I; Casas, Alejandro

    2016-01-01

    Transformation of natural ecosystems into intensive agriculture is a main factor causing biodiversity loss worldwide. Agroforestry systems (AFS) may maintain biodiversity, ecosystem benefits and human wellbeing, they have therefore high potential for concealing production and conservation. However, promotion of intensive agriculture and disparagement of TEK endanger their permanence. A high diversity of AFS still exist in the world and their potentialities vary with the socio-ecological contexts. We analysed AFS in tropical, temperate, and arid environments, of the Tehuacan Valley, Mexico, to investigate how their capacity varies to conserve biodiversity and role of TEK influencing differences in those contexts. We hypothesized that biodiversity in AFS is related to that of forests types associated and the vigour of TEK and management. We conducted studies in a matrix of environments and human cultures in the Tehuacán Valley. In addition, we reviewed, systematized and compared information from other regions of Mexico and the world with comparable socio-ecological contexts in order to explore possible general patterns. Our study found from 26 % to nearly 90 % of wild plants species richness conserved in AFS, the decreasing proportion mainly associated to pressures for intensifying agricultural production and abandoning traditional techniques. Native species richness preserved in AFS is influenced by richness existing in the associated forests, but the main driver is how people preserve benefits of components and functions of ecosystems. Elements of modern agricultural production may coexist with traditional management patterns, but imposition of modern models may break possible balances. TEK influences decisions on what and how modern techniques may be advantageous for preserving biodiversity, ecosystem integrity in AFS and people's wellbeing. TEK, agroecology and other sciences may interact for maintaining and improving traditional AFS to increase biodiversity

  1. Nutrient cycling and Above- and Below-ground Interactions in a Runoff Agroforestry System Applied with Composted Tree Trimmings

    NASA Astrophysics Data System (ADS)

    Ilani, Talli; Ephrath, Jhonathan; Silberbush, Moshe; Berliner, Pedro

    2014-05-01

    The primary production in arid zones is limited due to shortage of water and nutrients. Conveying flood water and storing it in plots surrounded by embankments allows their cropping. The efficient exploitation of the stored water can be achieved through an agroforestry system, in which two crops are grown simultaneously: annual crops with a shallow root system and trees with a deeper root system. We posit that the long-term productivity of this system can be maintained by intercropping symbiotic N fixing shrubs with annual crops, and applying the pruned and composted shrub leaves to the soil, thus ensuring an adequate nitrogen level (a limiting factor in drylands) in the soil. To test our hypothesis we carried a two year trial in which fast-growing acacia (A. saligna) trees were the woody component and maize (Zea mays L.) the intercrop. Ten treatments were applied over two maize growth seasons to examine the below- and above-ground effects of tree pruning, compost application and interactions. The addition of compost in the first growth season led to an increase of the soil organic matter reservoir, which was the main N source for the maize during the following growth season. In the second growth season the maize yield was significantly higher in the plots to which compost was applied. Pruning the tree's canopies changed the trees spatial and temporal root development, allowing the annual crop to develop between the trees. The roots of pruned trees intercropped with maize penetrated deeper in the soil. The intercropping of maize within pruned trees and implementing compost resulted in a higher water use efficiency of the water stored in the soil when compared to the not composted and monoculture treatments. The results presented suggest that the approach used in this study can be the basis for achieving sustainable agricultural production under arid conditions.

  2. REFORESTATION AND SEEDLING SYMBIONTS

    EPA Science Inventory

    Tree seedlings are dependent on symbiotic associations with microorganisms including bacteria, fungi, and actinomycetes for normal growth and development. itrogen fixing leguminous and non-leguminous trees form symbiotic relationships with Rhizobium (bacteria) and Frankia (actino...

  3. Eco-environment contribution of agroforestry to agriculture development in the plain area of China--Huai' an Prefecture, Jiangsu Province as the case study area.

    PubMed

    Ren, Hong-chang; Lu, Yong-long; Liu, Can; Meng, Qing-hua; Shi, Ya-juan

    2005-01-01

    For improving the environmental quality and ensuring supply of wood and non-timber forest products, many forests have been planted in plain areas of China. Scientists have studied their benefits, almost all of the approaches were based on fixed-point data, and few was considered on the non-efficient factors and temporal scale effects. This paper studies the positive and negative benefits at a large temporal scale, and the effects of plain afforestation on stockbreeding and rural economy. The benefits of plain afforestation, correlation coefficiency of agroforestry and production factors are analyzed via stochastic frontier modeling in Huanghuaihai Plain Area of China; elastic coefficient of agroforestry, husbandry, farming, and total output of agricultural sector are calculated through adopting partial differential equation. Some conclusions can be drawn that, plain forests have an important effect on the development of plain agriculture. But shelterbelts and small-scale forests have different effect on the development of agricultural economy. Shelterbelts have negative effect on the industries, but small-scale forest has positive effect. On the whole, contribution of forest resource to value of animal husbandry and gross production value of agriculture is positive, and to the value of farming is negative. PMID:16295915

  4. Agroforestry In-Service Training. A Training Aid for Asia & the Pacific Islands (Honiara, Solomon Islands, South Pacific, October 23-29, 1983). Training for Development. Peace Corps Information Collection & Exchange Training Manual No. T-16.

    ERIC Educational Resources Information Center

    Fillion, Jacob; Weeks, Julius

    The Forestry/Natural Resources Sector in the Office of Training and Program Support of the Peace Corps conducted an agroforestry inservice training workshop in Honiara, Solomon Islands, in 1983. Participants included Peace Corps volunteers and their host country national counterparts from six countries of the Pacific Islands and Asia (Western…

  5. Effects of Syn-pandemic Fire Reduction and Reforestation in the Tropical Americas on Atmospheric Carbon Dioxide During European Conquest

    NASA Astrophysics Data System (ADS)

    Nevle, R. J.; Bird, D. K.

    2008-12-01

    2000 BP correlate with expanding indigenous population, agriculture, and fire use in the tropical Americas. The rise in inter-site variability in charcoal accumulation after 2000 BP is consistent with a demographic shift toward sedentary agrarian communities and localized increases in charcoal accumulation in densely populated centers. Declines in regional charcoal accumulation and inter-site variability after 500 BP suggest a correlative cause related to reduction in anthropogenic biomass burning resulting from pandemic-driven population collapse. Published reconstructions of Pre-Columbian demography indicate that during European conquest, pandemics killed ~90% of the indigenous American population (~60 million), estimated to represent ~20% of the 16th century global population. Our predictive calculations suggest that fire reduction in the tropical Americas is associated with massive forest regeneration on ~5 x 105 km2 of land and sequestration of 5-10 Gt C into the terrestrial biosphere, which can account for 13- 50% of the ~2% global reduction in atmospheric CO2 levels and the 0.1‰ increase in δ13C of atmospheric CO2 from 1500 to 1700 CE recorded in Antarctic ice cores and tropical sponges. New archeological discoveries revealing extensive networks of geoglyphs and urban polities in Pre-Columbian Amazonia suggest that our estimates of reforestation, and consequent effects on atmospheric CO2, may be conservative.

  6. The rain-runoff response of tropical humid forest ecosystems to use and reforestation in the Western Ghats of India

    NASA Astrophysics Data System (ADS)

    Krishnaswamy, Jagdish; Bonell, Michael; Venkatesh, Basappa; Purandara, Bekal K.; Lele, Sharachchandra; Kiran, M. C.; Reddy, Veerabasawant; Badiger, Shrinivas; Rakesh, K. N.

    2012-11-01

    SummaryThe effects of forest degradation and use and establishment of tree-plantations on degraded or modified forest ecosystems at multi-decadal time-scales using tree-plantations on the streamflow response are less studied in the humid tropics when compared to deforestation and forest conversion to agriculture. In the Western Ghats of India (Uttar Kannada, Karnataka State), a previous soil hydraulic conductivity survey linked with rain IDF (intensity-duration-frequency) had suggested a greater occurrence of infiltration-excess overland within the degraded forest and reforested areas and thus potentially higher streamflow (Bonell et al., 2010). We further tested these predictions in Uttar Kannada by establishing experimental basins ranging from 7 to 23 ha across three ecosystems, (1) remnant tropical evergreen Forest (NF), (2) heavily-used former evergreen forest which now has been converted to tree savanna, known as degraded forest (DF) and (3) exotic Acacia plantations (AC, Acacia auriculiformis) on degraded former forest land. In total, 11 basins were instrumented (3 NF, 4 AC and 4 DF) in two geomorphological zones, i.e., Coastal and Up-Ghat (Malnaad) and at three sites (one Coastal, two Up-Ghat). The rainfall-streamflow observations collected (at daily and also at a 36 min time resolutions in the Coastal basins) over a 2-3 year period (2003-2005) were analysed. In both the Coastal and Up-Ghat basins, the double mass curves showed during the rainy season a consistent trend in favour of more proportion of streamflow in the rank order DF > AC > NF. These double mass curves provide strong evidence that overland flow is progressively becomes a more dominant stormflow pathway. Across all sites, NF converted 28.4 ± 6.41stdev% of rainfall into total streamflow in comparison to 32.7 ± 6.97stdev% in AC and 45.3 ± 9.61stdev% in DF. Further support for the above trends emerges from the quickflow ratio QF/Q for the Coastal basins. There are much higher values for both

  7. Drought effects on soil COagroforestry system in Sulawesi, Indonesia

    NASA Astrophysics Data System (ADS)

    van Straaten, O.; Veldkamp, E.; Köhler, M.; Anas, I.

    2009-12-01

    Climate change induced droughts pose a serious threat to ecosystems across the tropics and sub-tropics, particularly to those areas not adapted to natural dry periods. In order to study the vulnerability of cacao (Theobroma cacao) - Gliricidia sepium agroforestry plantations to droughts a large scale throughfall displacement roof was built in Central Sulawesi, Indonesia. In this 19-month replicated experiment, we measured soil surface CO2 efflux (soil respiration) in three simulated drought plots compared with three adjacent control plots. Soil respiration rates peaked at intermediate soil moisture and decreased under increasingly dry conditions (drought induced), but also decreased when soils became water saturated, as evidenced in control plots. The simulated drought plots exhibited a slight decrease in soil respiration compared to the control plots (average 13% decrease). The strength of the drought effect was spatially variable - while some measurement chamber sites reacted strongly ("responsive") to the decrease in soil water content (up to R2=0.70) (n=11), others did not react at all ("non-responsive") (n=7). The degree of soil CO2 respiration drought response was highest around cacao tree stems and decreased with distance from the stem (R2=0.22). A significant correlation was measured between "responsive" soil respiration chamber sites and sap flux density ratios of cacao (R=0.61) and Gliricidia (R=0.65). Leaf litter CO2 respiration decreased as conditions became drier. During dry periods the litter layer contributed approximately 3-4% of the total CO2 efflux and up to 40% during wet periods. A CO2 flush was recorded during the rewetting phase that lasted for approximately two weeks, during which time accumulated labile carbon stocks mineralized. The net effect on soil CO2 emissions over the duration of the experiment was neutral, control plots respired 11.1±0.5 Mg C ha-1 yr-1, while roof plots respired 10.5±0.5 Mg C ha-1 yr-1.

  8. Using Landsat Thematic Mapper records to map land cover change and the impacts of reforestation programmes in the borderlands of southeast Yunnan, China: 1990-2010

    NASA Astrophysics Data System (ADS)

    Zhang, Jialong; Pham, Thi-Thanh-Hiên; Kalacska, Margaret; Turner, Sarah

    2014-09-01

    At the beginning of the new millennium, after a severe drought and destructive floods along the Yangtze River, the Chinese government implemented two large ecological rehabilitation and reforestation projects: the Natural Forest Protection Programme and the Sloping Land Conversion Programme. Using Landsat data from a decade before, during and after the inception of these programmes, we analyze their impacts along with other policies on land use, land cover change (LULCC) in southwest China. Our goal is to quantify the predominant land cover changes in four borderland counties, home to tens of thousands of ethnic minority individuals. We do this in three time stages (1990, 2000 and 2010). We use support vector machines as well as a transition matrix to monitor the land cover changes. The land cover classifications resulted in an overall accuracy and Kappa coefficient for forested area and cropland of respectively 91% (2% confidence interval) and 0.87. Our results suggest that the total forested area observed increased 3% over this 20-year period, while cropland decreased slightly (0.1%). However, these changes varied over specific time periods: forested area decreased between 1990 and 2000 and then increased between 2000 and 2010. In contrast, cropland increased and then decreased. These results suggest the important impacts of reforestation programmes that have accelerated a land cover transition in this region. We also found large changes in LULC occurring around fast growing urban areas, with changes in these peri-urban zones occurring faster to the east than west. This suggests that differences in socioeconomic conditions and specific local and regional policies have influenced the rates of forest, cropland and urban net changes, disturbances and net transitions. While it appears that a combination of economic growth and forest protection in this region over the past 20 years has been fairly successful, threats like drought, other extreme weather events and land

  9. The effects of rainfall partitioning and evapotranspiration on the temporal and spatial variation of soil water content in a Mediterranean agroforestry system

    NASA Astrophysics Data System (ADS)

    Biel, C.; Molina, A.; Aranda, X.; Llorens, P.; Savé, R.

    2012-04-01

    Tree plantation for wood production has been proposed to mitigate CO2-related climate change. Although these agroforestry systems can contribute to maintain the agriculture in some areas placed between rainfed crops and secondary forests, water scarcity in Mediterranean climate could restrict its growth, and their presence will affect the water balance. Tree plantations management (species, plant density, irrigation, etc), hence, can be used to affect the water balance, resulting in water availability improvement and buffering of the water cycle. Soil water content and meteorological data are widely used in agroforestry systems as indicators of vegetation water use, and consequently to define water management. However, the available information of ecohydrological processes in this kind of ecosystem is scarce. The present work studies how the temporal and spatial variation of soil water content is affected by transpiration and interception loss fluxes in a Mediterranean rainfed plantation of cherry tree (Prunus avium) located in Caldes de Montbui (Northeast of Spain). From May till December 2011, rainfall partitioning, canopy transpiration, soil water content and meteorological parameters were continuously recorded. Rainfall partitioning was measured in 6 trees, with 6 automatic rain recorders for throughfall and 1 automatic rain recorder for stemflow per tree. Transpiration was monitored in 12 nearby trees by means of heat pulse sap flow sensors. Soil water content was also measured at three different depths under selected trees and at two depths between rows without tree cover influence. This work presents the relationships between rainfall partitioning, transpiration and soil water content evolution under the tree canopy. The effect of tree cover on the soil water content dynamics is also analyzed.

  10. Soil Infiltration Characteristics in Agroforestry Systems and Their Relationships with the Temporal Distribution of Rainfall on the Loess Plateau in China

    PubMed Central

    Wang, Lai; Zhong, Chonggao; Gao, Pengxiang; Xi, Weimin; Zhang, Shuoxin

    2015-01-01

    Many previous studies have shown that land use patterns are the main factors influencing soil infiltration. Thus, increasing soil infiltration and reducing runoff are crucial for soil and water conservation, especially in semi-arid environments. To explore the effects of agroforestry systems on soil infiltration and associated properties in a semi-arid area of the Loess Plateau in China, we compared three plant systems: a walnut (Juglans regia) monoculture system (JRMS), a wheat (Triticum aestivum) monoculture system (TAMS), and a walnut-wheat alley cropping system (JTACS) over a period of 11 years. Our results showed that the JTACS facilitated infiltration, and its infiltration rate temporal distribution showed a stronger relationship coupled with the rainfall temporal distribution compared with the two monoculture systems during the growing season. However, the effect of JTACS on the infiltration capacity was only significant in shallow soil layer, i.e., the 0–40 cm soil depth. Within JTACS, the speed of the wetting front’s downward movement was significantly faster than that in the two monoculture systems when the amount of rainfall and its intensity were higher. The soil infiltration rate was improved, and the two peaks of soil infiltration rate temporal distribution and the rainfall temporal distribution coupled in rainy season in the alley cropping system, which has an important significance in soil and water conservation. The results of this empirical study provide new insights into the sustainability of agroforestry, which may help farmers select rational planting patterns in this region, as well as other regions with similar climatic and environmental characteristics throughout the world. PMID:25893832