Agroforestry Model Research Articles

Analisis Pola Kemitraan Agroforestri dalam Rangka Mengurangi Ancaman Perambahan Hutan (Studi Kasus Tumpangsari Tanaman Pangan di IUPHHK-HT Pulau Laut Kotabaru Kalimantan Selatan)

Indonesia's forest covers about 133 million hectares. Local people of Pulau Laut in Kalimantan used to do shifting cultivation to manage their agricultural activities for food crops in the forest due to its poor soil of minerals and nutrients for years.The increased population and industrial development of forestry, plantation and mining caused decreasing of forest area, hence the shifting cultivation period has been shortened and encroach forest area. In consequence, degradation of the forest area is increasing.This study was conducted to identify how significant the role of agroforestry (“tumpangsari”) to prevent forest encroachment.The objectives of study were to analyze:(1) the contribution of agroforestry as forest partnership management to minimize the encroachment of forest area, (2) the “tumpangsari” cost and revenue,(3) the benefits of this program for local people, the estate forest company and for food security. In general, the growth of Acacia mangium planted in agroforestry model area has better performance compared with those planted in non agroforestry area significantly shown fortwo years of A.mangium growth period. The productivity of rice in “tumpangsari” model was 3.3 tones ha-1which higher than that of in shifting cultivation area in secondary forest of about 3.1 tones ha-1. The revenue from rice cultivation by “tumpangsari” model was Rp 10.032 million ha-1 and the production cost was Rp 5.932 million ha-1 and R/C ratio of about 1.69.This research pointed out that agroforestry have many benefits for minimize forest encroachment as it provides opportunity to increase the rice production through the partnership management on forest land without change its function.Keywords: agroforestry, “tumpangsari”, forest encroachment, partnership

Maize Response at Three Levels of Shade and its Improvement with Intensive Agro Forestry Regimes in Gunung Kidul, Java, Indonesia

This research was conducted to determine maize growth and yield at various agroforestry development levels, especially in Batur Agung area, Gunung Kidul District, Java, Indonesia. This experiment was conducted in a Randomized Complete Block Design (RCBD) single factor with three blocks as replication. Research factor was agroforestry development levels, namely, initial, intermediate, and advanced levels. Observations were done on maize growth and yield variables. Data then was analyzed by applying Analysis of Variance (ANOVA) at 5% level, and continued with the Duncan Multiple Range Test (DMRT) if significant.Maize physiological response on initial to intermediate and advanced agroforestry level demonstrated impairment tendency. This condition continued to maize production decline in line with shade level (initial AF, intermediate AF, and advanced AF). Traditional silvicultural developed with trees along border, alley cropping and mixer characteristics. Tree planting space was irregular with conventional stands management. Although the physiological response decreased in line with shade increase and so did maize production, farmers still continued to develop initial, intermediate, and advanced agroforestry models. Scheme developed to improve the productivity of agroforestry was constructing intensive agroforestry regimes (IAR). There are 3 IAR, namely, IAR-1 to hold initial agroforestry during the acceleration and management of initial agroforestry heading to intermediate and advanced. IAR-1 base is more intensive crown pruning and commercial thinning approach. Crop area was utilized during the management with C4 species. IAR-2 was designed to hold intermediate AF from traditional to intensive by applying intensive harvesting, with need based cutting and C3 species cultivation. IAR-3 was carried out for the development of advanced AF to initial AF with intensive need based cutting, pollarding, and intensive crop with C4 species.

Relative yield decomposition: A method for understanding the behaviour of complex crop models

Dynamic crop simulation models are widely used to investigate, through virtual experiments, the response of crop yield to changes in climate, management or crop genetic traits. In a search for widespread applicability, crop models include a large number of processes, sometimes to the detriment of their mathematical transparency.Simulated crop yield responses to variation in model inputs result from the integration over a long period (one or several years) of many different crop processes interacting at the model time-step, typically the day. Thus, by definition, yield explanatory factors are intricate and difficult to link efficiently to the crop processes. Ranking their relative contributions to the final yield output is for example almost impossible.In this work, we introduce a new approach to understand the response of crop yield Y by comparing two simulation runs (computing two yields Y1 and Y2) of the same model and by focussing on the relative yield: y = Y1/Y2. Providing that the mathematical formulation of the dynamic crop model verifies simple hypotheses held by most crop models, we show that it is possible to factorise the relative yield y into several terms. These terms can be (i) interpreted as the specific effects of the modelled crop processes on the crop yield, (ii) compared to rank the effects of the crop processes on the crop yield. Their definition involves using state variables of the model computed during the simulation runs. The method does not involve running the model numerous times, neither changing its formulation. It may require to output new variables that are not in the set of variables proposed by the released version of the model. We call our method the relative yield decomposition (RYD) method.We illustrate how the RYD provides insight in the analysis of complex crop models by applying it to two models: Yield-SAFE (agroforestry model) and STICS (crop model). The method allows to identify and quantify the importance of the main processes responsible for crop yield variations for different simulation configurations in the two models.The relative yield decomposition method is complementary to other model analysis methods like sensitivity analysis or multiple model simulations. We show that it could be applied to some widely used crop models (e.g. AQUACROP, CERES, CROPGRO, CROPSYST, EPIC, SIRIUS, SUCROS). The relative yield decomposition method appears as a powerful and generic tool to analyse the behaviour of complex crop models that can help to improve the formulation of the models, or even to study specific plant traits or crop processes when applied to a model accurate enough.

Sustainable agricultural intensification: the role of cardamom agroforestry in the East Usambaras, Tanzania

The East Usambaras in Tanzania are a tropical biodiversity hotspot where current agricultural management practices pose threats to forest conservation and development objectives. Promoting sustainable agricultural intensification (SAI) would improve long-term productivity and reduce pressure on forest reserves. The study objective was to identify household-level characteristics that influence adoption of improved management practices, specifically soil replenishment practices, in order to identify opportunities and constraints to scaling up SAI to landscape level. First, three common farming systems and a fourth agroforestry (AF) model were developed to estimate the relative profitability of incorporating fallow, manure, and non-timber forest product activities. Next, household surveys were conducted and a logistic regression analysis was used to measure the influence of socioeconomic characteristics, physical and financial assets, tenure security, and plot-specific attributes on adoption of soil replenishment practices that were specified in the model. Findings showed that the AF model was financially competitive but raises opportunity costs to labour when compared to common systems. Marital status, household size, remittances, credit access, and tenure security significantly influenced adoption of fallow and applying organic inputs. Significant plot-specific attributes included perceived fertility and distance from the homestead. Policies to scale up SAI should consider these factors and emphasize improving markets for AF species and extension services.

Increasing Tree Cover in Degrading Landscapes: ‘Integration’ and ‘Intensification’ of Smallholder Forest Culture in the Alutilla Valley, Matiranga, Bangladesh

Abstract Research was conducted in Alutilla Valley in eastern Bangladesh to identify the nature of existing agroforestry systems and to identify potential agroforestry models that could ameliorate currently degrading forest resources Data were collected through farmer participatory research and a structured quarterly survey in two villages. Qualitative and supplementary quantitative analysis methods were used to assess the financial potential of agroforestry systems. Various patterns of agroforestry exist in the study site, but all have two common principles, namely ‘integration with agriculture’ and ‘multi-functionality’. Two agroforestry models suitable for adoption by farmers have been identified. Multi-strata agroforestry, based on a fruit and timber tree canopy with vegetables and tuber species in the understorey, can be practiced in the shifting cultivation fields near settlements. Fruit and timber tree-based conservation agroforestry is well suited to manage large-scale biologically depleted landscapes. Both systems yield early financial returns, facilitating the change from shifting cultivation to multi-strata agroforestry or fruit and tree-based conservation agroforestry.

Developing Mechanism of Rubber-tea-chicken Agro-forestry Model in Tropical Area of China

Abstract As a typical tropical agro-forestry ecosystem in Wenchang, Hainan Province, China, rational mechanisms of the rubber-tea-chicken eco-agricultural model were studied with the Solow technological level index, stability indicator, harmonizing coefficient, grey correlation coefficient and production dominance. This study focused on rational hierarchical structure, the limiting factors and optimal strategies of the model development based on model structure, resource conditions and external market demands. Results showed that rational mechanism of the rubber-tea-chicken ecosystem model mainly included technological contributions, leverage function of dominance component (livestock husbandry), stability of the model structure and harmony of its components, the model dominant product’s market demand and government’s supporting policies. The contributions of fund, technology, information and talent resources played an important role in improving sustainability and productivity of the agro-forestry model.

Nutrient cycling in Casuarina (Casuarina equisetifolia) based agroforestry system

The present report gives an account of the results of research carried out on litter production, accumulation and nutrient return through rainfall, stem flow, throughfall and interception to soil litter fall, under Casuarina-Black Gram Agroforestry Models (age 4 years, density 650 trees/ha). It was found that of the total rainfall (497.9 mm) 1.2% was recorded as stem flow and 80% as throughfall while the interception accounted for 19 %. It is found that on an average annual basis, of the total uptake of various nutrients was retained in the non-photosynthetic biomass and the rest returned to soil. These results show that among the nutrients, maximum annual retention was accounted for potassium while, the minimum for nitrogen. This paper deals the nutrient accumulation in standing crop, nutrient concentration and return, rainfall interception, nutrient concentration in rain wash, nutrient return through rain wash and Nutrient retained, returned and uptake (kg/ha/yr) in Casuarina under Agroforestry System in detail.

Simple models for light competition within agroforestry discontinuous tree stands: are leaf clumpiness and light interception by woody parts relevant factors?

Predicting the temporal and spatial variability of radiation intensity under wide-spaced tree stands is required for many applied issues in savannah-like ecosystems, orchards, agroforestry and urban forestry systems. Numerous authors have advocated the use of simple light interception models that approximate the crown shape with ellipsoids. They have suggested taking into account leaf clumping to improve the efficiency of these simple models, but this was never assessed. We tested this hypothesis together with the impact of including predictions of light interception by woody parts (trunks, branches). We calibrated and evaluated the model using cross-validation across eight walnut trees with field measurements of radiation intensity and spatial heterogeneity using hemispherical photographs. Leafless trees were efficiently modelled using Wood Area Density (WAD, m2m−3) for branches and an opaque cone for the trunk. We introduced a clumping parameter (μ) but this proved inefficient, clumping being highly variable amongst trees. This results from the limitations of representing the crown as an ellipsoid, a procedure too coarse to be improved by using a clumping parameter. The model proved efficient to predict the light pattern around an average tree, but was not fit for simulating the variability of individual trees. We finally discuss practical recommendations for modelling light competition in integrated agroforestry models simply.

Agroforestry: An Integrated system for conservation of natural resources in Northern India

The present paper deals with the land degradation in shiwaliks and deliberation of suitable Agroforestry Models for conservation and sustainable production of natural resources in this region. The Agroforestry practices recommended vary from silvipasture systems to meet fuel wood and fodder demands to agrisilviculture system (Poplar +Wheat +Fodder; Quercus+ Maize-Wheat; Grewia + Soybean - Wheat etc.) for food and fodder, hortisilvipasture system (Mango + Poplar + Paddy - Wheat; Plum + Morus + Soybean – Wheat; Apple + Pea, etc) for fruit, fodder and other products. The paper also highlights the employment opportunities through Agroforestry in the region.

Agroforestry Interventions across different Agroclimatic zones in Maharashtra, India

All India Co-ordinated Research Project on Agroforestry, College of Agriculture, Nagpur, have developed Teak and Bamboo based Agri-silviculture System. In the present study production and economics of Teak and Bamboo based Agri-silviculture System is discussed. Economic and ecological viability were studied and the Agroforestry models have been released for cultivation in semiarid region of the state.

ECONOMIC FEASIBILITY AND BIOLOGICAL PRODUCTIVITY OF COCONUT-BASED AGROFORESTRY MODELS IN SRI LANKA

This study evaluates the economic feasibility and biological productivity of coconut-based agroforestry models designed for coconut smallholders. Coconut Research Institute of Sri Lanka has developed and established twenty-six agroforestry models in farmers' fields. Of them, four models were selected for this study. They were: mixed farming for Wet Zone (model 1), mixed cropping for Wet Zone (model 2), mixed farming for Wet Intermediate Zone (model 3) and catch cropping in young replanted coconut for Wet Intermediate Zone (model 4), established at Gaspe, Hanchapola, Katuneriya and Thulawala, respectively. Input and output data for several years, for each model, were used in the evaluation. Annual Gross Margins (GM) payback period, Net Present Value (NPV) and Benefit-Cost Ratio (BCR) were employed for the economic analysis. Biological productivity of the models was. determined employing Land Equivalent Ratio (LER) and Relative Yield Total (RYT). NPVs of agroforestry models were higher than the monocrop, suggestingthe higher net worth of the agroforestry models in the long run. Othereconomic indicators also showed that agroforestry models were moreprofitable than coconut monoculture. In all models, LER exceeded unity,indicating the yield advantage with agroforestry over coconut monocultures.However, RYT values indicated that there were negative interactionsbetween component crops of certain models, which can be attributed to thecompetition that occurs between crops.

SOCIAL ACCEPTABILITY OF COCONUT-BASED AGROFORESTRY MODELS DEVELOPED TO SMALLHOLDERS IN SRI LANKA

Coconut Research Institute of Sri Lanka (CRISL) has designed andestablished twenty-six coconut-based agroforestry models in differentagroecological regions of smallholder coconut farmers' fields commencing1987. This study evaluates the conformity of four selected models with theexisting resource base of smallholder coconut farmers and elicits theirperceptions on these models. The selected models include: mixed farmingfor Wet Zone (model 1), mixed cropping for Wet Zone (model 2), mixedfarming for Wet Intermediate Zone (model 3) and intercropping for WetIntermediate Zone (model 4), established respectively at Gaspe,Hanchapola, Katuneriya and Thulawala. Conformity of these models withthe existing resource base of the farmers was analyzed by comparing laborand cash requirement of the models with the availability of these tworesources at farmers' disposal while the farmers' perceptions were elicitedthrough a survey using a structured questionnaire supplemented withinformal discussions. Results revealed that all the selected agroforestrymodels conform with the existing cash resource base of the farmer atcurrent scale of operation, but not so with the family labor supply. However,both these resources may turn out to be limiting constraints once the currentscale of operation is expanded. The farmers' expressed mix perceptions onagroforestry models in terms of model layout, crop composition, suitability tosocioeconomic circumstances etc, with an overall positive assessmentimplying that the models developed by the CRISL are acceptable for them.

Socio economic studies of Henwal watershed, Tehri Garhwal, Uttarakhand

The paper describes the socio-economic conditions and some strategies to restore the productivity of eight villages in Henval Watershed in the Tehri Garhwal Himalayas. The study reveals that the ratio of female to male population is more due to migration of males in search of livelihood to the other places. The average livestock varies from 4.43 to 5.40 per family and average land holding from 0.26 ha (Manjyar) to 1.52 ha (Jaul). Almost all the families in surveyed villages are engaged in farming and their average annual income per family per year is very low and varies from Rs 4000/- to Rs 6500/- per month. Fodder and fuel wood collection is done from the nearby forests, mainly by the women and children of the family and they spend 3 to 4 hours in these activities. Due to grazing of animals and collection of fodder and fuel wood, these activities cause environmental depletion It is suggested that afforestation of village forest /community land through Agroforestry models like silvipasture/ silvihorti system etc, can provide a key to the economic prosperity of the rural hills and would also be helpful in fulfilling the requirements of local inhabitants and ultimately balancing the whole ecology of the Garhwal Himalayas.

Participatory technology development for incorporating non-timber forest products into forest restoration in Yunnan, Southwest China

Indigenous knowledge has become a topic of considerable interest within the research and development environment. Incorporating indigenous knowledge into state-led ‘top-down’ conservation and development programmes, however, is still a great challenge. This paper presents a case from Yunnan, Southwest China, in which indigenous knowledge has been integrated into the development of an agroforestry model with non-timber forest products for the Sloping Land Conservation Programme (SLCP) by using a participatory technology development (PTD) approach. This approach was adopted to increase the likelihood that technologies developed would be suitable for resource-poor households. It is expected that integrating indigenous and scientific knowledge, will lead to positive ecological and economic outcomes. Finally, the paper argues that the integration of indigenous knowledge in both forestry policy formulation and implementation is important in the context of sustainable forest management in mountain areas.

Economic analysis of bamboo based agroforestry system in eastern and south eastern coastal plains of Orissa

Bamboo is one of the fastest growing species amongst the number of multipurpose tree species. It is socially acceptable with broad adaptability because of its versatile and multifarious uses which contribute valuably towards the human economy providing variety of goods. Looking to the global scenario of the increasing demand and decreasing supply of Bamboo for industrial as well as commercial purposes, cultivation of Bamboo through Agroforestry practices seems to have high economic return. The paper focusses on economic analysis of Agroforestry models of Bamboo cultivation through flute methods. In the present study the NPV, BCR and IRR are obtained as Rs.72550, 2.93 and 47.85 respectively at 10% discounted rate of interest.

Performance of an improved fallow system in the Peruvian Amazon—modelling approach

As traditional slash-and-burn systems with prolonged fallow periods are no longer feasible in most parts of the tropics, improved agroforestry systems have high potential to increase the productivity of farming systems and sustain continuous crop production. Our objective was to assess biophysical and economic performance of planted leguminous tree fallow (using Inga edulis) compared to the traditional slash-and-burn farming system, practiced by farmers on fields infested with noxious weedy grass Imperata brasiliensis around the city of Pucallpa, Peru. An existing agroforestry model SCUAF was used to predict biophysical factors, such as changes in soil characteristics and farm outputs (crop and tree yield). While a cost-benefit analysis spreadsheet, which uses the output from SCUAF and economic data on input/output levels and prices, calculates economic performance of the systems. The Inga fallow system can provide improvements to a range of soil biophysical measures (C, N, P content). This enables higher levels of farm outputs to be achieved (higher cassava yields). However, for smallholders the improved system must be more economically profitable than the existing one. At prices currently encountered, the Inga fallow system is more profitable than the Imperata fallow system only in the long-term. In adopting the Inga fallow system, smallholders will incur lower profits in the first years, and it will take approximately 10 years for smallholders to begin making a profit above that achievable with the Imperata fallow system. Unless smallholders are capable of accepting the lower profitability in first years, they are less likely to adopt the new system.

The Link Between Community Forestry Policies and Poverty and Unemployment in Rural Nepal

The present article examines the relationship between community forest management policies on the one hand, and income and unemployment in rural areas of Nepal on the other, by modeling the effect of forest management constraints on community forest use. Current government policy dictates the use of all community forestland for environmental conservation and limited timber production, and provides little scope for fodder and firewood production. Based on data from 259 households in 6 community forest user groups in 3 hilly districts (Dolakha, Kavre, and Nuwakot), the results show that the resources available from private lands and community forests under current policies are inadequate to fully utilize the family labor force of many rural households, and are insufficient to generate a bare subsistence income for the poorest households. The study shows that a policy change to community forest management using a more flexible agroforestry model could overcome rural unemployment problems and increase incomes while ensuring sustainable resource use from the forests.

K AND Na LEACHING FROM LEAF LITTER OF ACACIA AURICULIFORMIS (CUNN. EX BENTH.)

Acacia auriculiformis (Cunn. Ex Benth.) is now widely planted in different agroforestry models. The prime use of this species is for fuel wood and to some extent as furniture timber at the northern and central part of Bangladesh. In agroforestry, trees and agricultural crops sharing the nutrients from the same piece of land. Trees uptake nutrients from the soil and some portion of that nutrient again back to the soil through the leaching process and decomposition of litter. K and Na leaching from leaf litter of Acacia auriculiformis was studied in the laboratory. About 16% of initial dry weight of leaf litter was lost after 168 hours. Weight loss of leaf litter, conductivity and TDS (Total Dissolve Solid) of leached water showed significant (p<0.05) positive curvilinear relationship with leaching time. The initial concentration of K and Na in leaf litter significantly (p<0.05) decreased to 2247 mg g-1 and 735 mg g-1 respectively after 96 hours and showed significant (p<0.05) negative curvilinear relationship with weight loss. The pattern of K and Na leaching from the leaf litter of Acacia auriculiformis might help agroforestry practitioners to add a new criteria to choose potential tree species for their farming system.

Role of agroforestry in integrated ecosystem management - A case of success

Annual forest degradation rate in our country is about 0.15% or 95 thousand ha and out of total agricultural land in India a major part (105 million ha) is under rainfed agricultural practices. Thus there is a need to develop the degraded land to maintain the current rate of forest productivity. The traditional agricultural practices and forestry are constrained by their limited inherent capacity of productivity. Agroforestry, spanning both the land use systems – agriculture and forestry obviously a viable alternative which take care of the objectives of both systems i.e. food security and ecological stability of forest simultaneously. Through this study an attempt has been made to develop a suitable Agroforestry models for reclamation of the vast chunk of red lateritic wastelands in the State of West Bengal in association with the local NGOs and the indigenous people that is the need for the hour. It is found through this field experiment that with the right kind of technology and selection of better combination of different tree species and intercrops with little external input even the gravelly lateritic barren wasteland can be reclaimed as ecologically and economically productive ones.

Spatial distribution of root length density and soil water of linear agroforestry systems in sub-humid Kenya: implications for agroforestry models

In simultaneous agroforestry systems trees can compete with crops for water, especially in semi-arid areas. However, in the (sub)humid tropics, on P-fixing Oxisols/Ferralsols small decreases in soil water content caused a decrease in P-transport to roots and therewith a soil-drying induced P-deficiency. The aim of this study was to assess the spatial distribution of soil water content in crop fields bordering tree lines and its relation with root length density distribution of the trees throughout the soil profile. To achieve this, soil water content and tree root length densities throughout the soil profile were measured over a period of 2 years in an experiment with lines of four tree species in the middle of maize fields in sub-humid western Kenya. Soil water content was significantly reduced (2–7 vol.%) near two of the three fast-growing tree species, Eucalyptus grandis and Grevillea robusta, but not near Cedrella serrata and the slower growing Markhamia lutea. These differences were related to differences in water use. Eucalyptus and Grevillea showed high water use and Cedrella and Markhamia low water use. However, soil water content distribution was not related to root length density distribution. Root length densities hardly decreased with distance to Grevillea and clearly decreased with distance to Cedrella. Most water-uptake models, including those of agroforestry models, assume that root length density distribution throughout the profile is proportional to water extraction throughout the profile. The absence of a clear relation between root length density and water extraction near Grevillea tree lines opposed this view. It can be explained by a decrease in water-potential gradient between root and soil at increasing distance from the tree base. If the change in root length density is similar or smaller than the change in water-potential gradient between root and soil, the decrease in water-potential gradient between root and soil is of similar or larger importance for determining tree-water extraction distribution throughout the profile than root length density. Thus, modeling of spatial agroforestry systems cannot assume a direct relation between tree-water extraction and root length density, but needs to include decreasing water-potential gradient between root and soil along roots with increasing distance to the stem base, especially over the horizontal dimension.