Shaded Coffee Systems Research Articles

Effect of local habitat and landscape attributes on bird communities in shade coffee plantations in the Colombian Andes

Agroforestry is increasingly promoted to support biodiversity conservation by increasing tree cover in agricultural landscapes, but the extent to which landscape context affects how benefits accrue remains uncertain. We used shade-coffee systems to ask how the proximity and extent of forest and forest-agriculture mosaic in the landscape influenced bird communities in 160 coffee plantations that differed in coffee plant density and shade tree richness and abundance in two departments of Colombia with differing regional forest cover. Our findings suggest that regional forest cover and landscape conditions can mediate the response of birds to local habitats on plantations. Avian richness and community completeness was positively related to the amount of forest-agriculture mosaic within landscapes surrounding coffee plantations only within the comparatively forested department of Antioquia (mean 32 % regional forest cover), particularly where plantations had high richness and abundance of trees. In the largely deforested department of Cauca (mean 1 %), neither distance to forest nor cover by forest-agriculture mosaics explained avian richness and community completeness, both of which were positively related only to local tree richness and abundance. We show that biodiversity benefits from increasing habitat quality at local and landscape scales, and habitat quality within plantations becomes increasingly influential as the amount of habitat in the broader landscape declines. Our results emphasize the role of landscape context in conservation planning to promote biodiversity in coffee-growing regions.

Perennial species diversity, ecosystem carbon stocks and carbon income in coffee-based agroforestry systems along an elevation gradient in South-eastern Ethiopia

In the current context of deforestation, coffee-based agroforestry system (CAFS) is credited for climate change (CC) mitigation and biodiversity conservation while supporting local livelihoods. Despite integrating shade tree species in CAFS, empirical studies to support this assertion are inadequate in Eastern Africa, and hence, its ecosystem services provisions are less understood. We evaluated perennial species diversity, carbon (C) stocks in the biomass and soil organic C (SOC) along an elevation gradient of 72 plots of shade coffee, while 36 plots were selected for without-shade coffee systems within three elevations, namely, low (1600–1750 masl), mid (1750–1850 masl) and high (1850–2000 masl) elevations in Southeastern Ethiopia. The perennial species diversity and biomass, SOC, fine root and litter C stocks were evaluated. Perennial species Shannon diversity significantly differed among the studied elevations (p < 0.001). Shaded coffee had significantly higher ecosystem C stocks than without shaded coffee systems (p < 0.05). The highest C stocks were found in the soil in both coffee systems. However, we found a weak relationship between the Shannon diversity and biomass C. The C income in shaded coffee was 70 % higher than without shaded coffee systems. The present study showed that shaded coffee accumulates more C and provides additional benefits from C credits. Hence, CAFS deliver ecosystem services that enhance biodiversity conservation and CC mitigation while generating an additional C income for farmers. However, we learned that the impact of perennial plant diversity on C stock and C income is context and site-specific.

The coffee-mango association promotes favorable soil conditions for better-nourished and higher-yielding plants

In several countries, coffee is traditionally grown under the shade of large trees; however, the non-shade surface system has increased. Shade cultivation system benefits the soil, helps crops adaption to climate change, and reduces vulnerability. This study aimed to compare the physical, chemical, and biological soil features under coffee production systems: coffee-mango, coffee-banana, and full-sun coffee; to identify the nutritional variation of coffee plants in the three cultivation systems, and to establish recommendations for coffee production associated with other crops. Soil properties varied between the shaded and full-sun systems. The shade coffee systems had different pH, cation exchange capacity, potassium, and nitrogen concentrations, organic matter, carbon-, nitrogen-microbial biomass, and the number of earthworms from the full-sun coffee system. The coffee-mango association showed specific soil (exchangeable calcium, moisture, soil porosity, and aggregate stability index), foliar (calcium, potassium, nitrogen, iron, and chlorophyll a and b concentrations), and grain features (gold coffee yield, potassium, magnesium, and phosphorous concentrations) that make distinct from the other two coffee systems. The coffee-mango system positively influenced soil traits, nutrient concentration in leaves, production, yield, and nutritional status of the fruit. The production of coffee under full-sun adversely affects the soil and the coffee’s nutrition and yield. Therefore, the production of coffee should be in the traditional manner under shade trees. These results apply to coffee production under shade systems in other countries with similar agroecological conditions and to soil conservation as a pertinent vision under global climate change.

Differential effects of ants as biological control of the coffee berry borer in Puerto Rico

Conservation biological control consists of managing agroecosystem to maintain and enhance the action of natural enemies. Agroforestry systems such as shaded coffee system has been shown to maintain high diversity of organisms, including predators and parasitoids of insect pest. The coffee berry borer (CBB), Hypothenemus hampei, is one of the most widely distributed coffee pests frequently causing severe economic damage. Ants have been reported as natural enemies of the CBB, but different species of ants are known to have different and sometime contrasting effects against the CBB. In this study, we examine the damage and survival of CBB on coffee plants that are dominated by six different species of ants, Solenopsis invicta, Wasmannia auropunctata, Monomorium floricola, Paratrechina longicornis, Brachymyrmex heeri and Pheidole moerens, in Puerto Rico. This represents a novel community of natural enemies since four of the six species are non-native. We hypothesized that the large and dominant species, S. invicta, would reduce the damage of the CBB by preying on adult CBB outside the berries, while the smaller species, would reduce the survival of the CBB by preying on the reproducing adults inside the berries (and potentially also on the immature stages, although not quantified in this study). Results show that S. invicta was associated with significantly reduced CBB damage. The only species associated with reduced survival of CBB inside berries was W. auropunctata, whereas the others were not associated with any effect on survival. Surprisingly, P. moerens and P. longicornis had a significant positive effect on the damage of the CBB suggesting that these species could only forage on plants that did not harbor S. invicta or W. auropunctata, the two most aggressive ants both of which were associated negatively with the CBB. The study also suggests that the negative impact of S. invicta on W. auropunctata indirectly facilitates the CBB by protecting it from predation by W. auropunctata once the adult CBB gains entrance to the coffee berry.

Temporal dynamics and biocontrol potential of a hyperparasite on coffee leaf rust across a landscape in Arabica coffee’s native range

Agroforestry systems can provide habitats for a rich biodiversity including multitrophic interactions, which presents opportunities to develop natural pest control. Shade coffee systems in several coffee growing areas of the world host such unique habitats where pests and their natural enemies interact. One of the major global challenges for coffee production, coffee leaf rust caused by the fungal pathogen Hemileia vastatrix is attacked by the fungal hyperparasite, Lecanicillium lecanii. However, we lack insights in the dynamics and biocontrol potential of the hyperparasite on coffee leaf rust from landscapes in Arabica coffee’s native range. To understand the temporal dynamics across landscapes and environmental drivers of the rust and hyperparasite, and the potential for biocontrol of the rust by the hyperparasite, we studied the rust and hyperparasite during the dry and wet seasons for three consecutive years at 60 sites across a gradient of coffee management in southwestern Ethiopia. We found that coffee leaf rust was more severe during the dry season, whereas the hyperparasite was more severe during the wet season in two out of three years. The rust growth rate from the wet to the dry season transition was negatively related to the hyperparasite index during the wet season, implying a potential top-down control. Coffee leaf rust was generally more severe at lower altitudes in the dry season, whereas the hyperparasite was more severe at high altitude. The rust incidence increased with management intensity, while the hyperparasite was more common under less intensive management. This study could be interesting in that it represents a landscape where Arabica coffee originated and the rust and hyperparasite might have a long co-evolutionary history. Our findings highlight the potential of the hyperparasite to suppress the rust’s growth rate from the wet to dry season transition when the rust severity could otherwise be at its peak. We show that less intensively managed landscapes with dense shade levels are likely to increase hyperparasite abundance and result in an improved top-down control of the rust. However, more detailed knowledge is needed on the interaction of these species to assess its importance for reducing rust induced yield losses or the risk of rust outbreaks.

Microclimate and soil and water loss in shaded and unshaded agroforestry coffee systems

The agroforestry systems are a potential pathway to improve soil quality and protect against extreme temperatures that negatively impact coffee growth. However, more studies about the effects of inclusion of tree elements in coffee systems soil and water loss dynamics are needed. This study aimed to understand how the inclusion of trees influences the microclimate and soil and water loss in shaded compared with unshaded coffee systems. Two pluviometers, one in shaded and the other in unshaded area, were installed to record hourly data from August 2009 to June 2010. Soil temperature and moisture were monitored by a system of sensors: air temperature, soil temperature at 10 cm depth, and soil moisture at 10, 30 and 100 cm depths, recording data at hourly intervals from August 2009 to June 2010. The surface water runoff and soil mass lost by laminar erosion were measured using collectors. Air temperature under shaded conditions had less variation than under unshaded conditions and lower maximum temperatures. Soil and water loss of both systems were small due to the high soil cover. Our results indicate that the water loss was higher in the unshaded area (338 L ha−1) during the study period compared with the shaded system (150 L ha−1). Soil temperature was lower under shaded conditions and there was water absorption complementarity between coffee and trees in shaded area. Soil moisture of shaded area was lower than unshaded area for all depths in all monitored period. Therefore, the shaded agroforestry coffee systems improve microclimate conditions and deep water drainage compared with unshaded coffee systems.

Soil organic carbon storage by shaded and unshaded coffee systems and its implications for climate change mitigation in China

AbstractShaded coffee systems can mitigate climate change by fixation of atmospheric carbon dioxide (CO2) in soil. Understanding soil organic carbon (SOC) storage and the factors influencing SOC in coffee plantations are necessary for the development of sound land management practices to prevent land degradation and minimize SOC losses. This study was conducted in the main coffee-growing regions of Yunnan; SOC concentrations and storage of shaded and unshaded coffee systems were assessed in the top 40 cm of soil. Relationships between SOC concentration and factors affecting SOC were analysed using multiple linear regression based on the forward and backward stepwise regression method. Factors analysed were soil bulk density (ρb), soil pH, total nitrogen of soil (N), mean annual temperature (MAT), mean annual moisture (MAM), mean annual precipitation (MAP) and elevations (E). Akaike's information criterion (AIC), coefficient of determination (R2), root mean square error (RMSE) and residual sum of squares (RSS) were used to describe the accuracy of multiple linear regression models. Results showed that mean SOC concentration and storage decreased significantly with depth under unshaded coffee systems. Mean SOC concentration and storage were higher in shaded than unshaded coffee systems at 20–40 cm depth. The correlations between SOC concentration andρb, pH and N were significant. Evidence from the multiple linear regression model showed that soil bulk density (ρb), soil pH, total nitrogen of soil (N) and climatic variables had the greatest impact on soil carbon storage in the coffee system.

Soil fungal communities differ between shaded and sun-intensive coffee plantations in El Salvador.

Coffea arabica is a highly traded commodity worldwide, and its plantations are habitat to a wide range of organisms. Coffee farmers are shifting away from traditional shade coffee farms in favor of sun-intensive, higher yield farms, which can impact local biodiversity. Using plant-associated microorganisms in biofertilizers, particularly fungi collected from local forests, to increase crop yields has gained traction among coffee producers. However, the taxonomic and spatial distribution of many fungi in coffee soil, nearby forests and biofertilizers is unknown. We collected soil samples from a sun coffee system, shade coffee system, and nearby forest from Izalco, Sonsonate, El Salvador. At each coffee system, we collected soil from the surface (upper) and 10 cm below the surface (lower), and from the coffee plant drip line (drip line) and the walkway between two plants (walkway). Forest soils were collected from the surface only. We used ITS metabarcoding to characterize fungal communities in soil and in the biofertilizer (applied in both coffee systems), and assigned fungal taxa to functional guilds using FUNGuild. In the sun and shade coffee systems, we found that drip line soil had higher richness in pathotrophs, symbiotrophs, and saprotrophs than walkway soil, suggesting that fungi select for microhabitats closer to coffee plants. Upper and lower soil depths did not differ in fungal richness or composition, which may reflect the shallow root system of Coffea arabica. Soil from shade, sun, and forest had similar numbers of fungal taxa, but differed dramatically in community composition, indicating that local habitat differences drive fungal species sorting among systems. Yet, some fungal taxa were shared among systems, including seven fungal taxa present in the biofertilizer. Understanding the distribution of coffee soil mycobiomes can be used to inform sustainable, ecologically friendly farming practices and identify candidate plant-growth promoting fungi for future studies.

Elite-led development and Mexico’s independent coffee organisations in the wake of the rust epidemic

Between 2012 and 2016 a virulent strain of coffee rust reduced Mexican yields by more than 50%, and it is still devastating production. The government has responded by replacing traditional arabica plants vulnerable to the pathogen with resistant, high-yielding varieties to recover the sector and encourage long-term adaptation to a disease that cannot be eradicated. However, this contribution will attempt to show that the intractable nature of the epidemic and the biological characteristics of resistant varieties threaten the survival of independent coffee organisations and their agroecological shade coffee systems. With little or no possibility of recovering production without the use of resistant plants, the alternative production and marketing models that these organisations have constructed over the past three decades face unprecedented challenges.

The Economics and Ecology of Shade-grown Coffee: A Model to Incentivize Shade and Bird Conservation

Shade-grown coffee, which is grown under a forest-like canopy of trees, is a production system widely regarded as environmentally sustainable and enabling for biodiversity conservation. Although shade-coffee systems enhance pest-control services from birds, there is an important potential tradeoff, namely lower coffee yields. Yet few studies have explicitly examined this tradeoff and the economic incentives required for smallholders to adopt shade practices rather than conventional systems, in which coffee is grown in full sun or little shade. We formulated a dynamic optimization problem to model a grower's decision to convert land from conventional to shade-grown production based on (1) expected yields and costs of each system, (2) gains from pest-control services provided by birds and (3) price premiums for higher-quality, sustainably-grown coffee. Our results suggest that at least 36% of a five-hectare farm should be allocated to shade-grown coffee to maximize inter-temporal income. This proportion is positively related to (1) production savings associated with birds, (2) prices for shade-grown and conventional coffees, (3) number of trees used for shade and (4) yields of shade-grown coffee. We show that smallholders have incentives to allocate more land to shade-grown coffee when they benefit from bird conservation under the appropriate market conditions.

Elevation and cropping system as drivers of microclimate and abundance of soil macrofauna in coffee farmlands in mountainous ecologies

Unravelling how earthworms and ants are deterministically structured by abiotic and biotic factors is of utmost relevance in fostering favourable environments for their increased abundance and action, more so in the increasingly degraded agricultural ecosystems of mountainous regions in sub-Saharan Africa. The Mount Elgon region (MER) of Uganda is characterised by mosaics of farmlands dominated by Arabica coffee with variability in inclusion of companion crops and shade trees, and in use of organic and inorganic fertilizers; and elevation. In this paper we explored abundance of soil macrofauna and microclimate patterns in different cropping systems at varying mountain elevations. The study covered 72 coffee fields delineated by 3 elevation categories: low, mid and high; and 4 cropping systems: Coffee monocrop (C), Coffee + annual crop (C + A), coffee + banana (C + B), and coffee + banana + shade trees (C + B + T). Results indicated that ant abundance at high elevation was thrice that of low and was same order of magnitude in unshaded than in banana- and tree-shaded systems. Earthworm abundance followed a different trend, decreasing with altitude except in C + B and C + A systems. Some of these relationships could be explained by ambient temperature, light intensity and soil electrical conductivity in the systems. Earthworms preferred less-illuminated shaded coffee systems at warmer low-mid elevations and soils with relatively high electrical conductivity whereas ants’ counts were depressed by such systems, and mostly driven by cooler higher elevations. These results show that agricultural practices at the field scale have notable impact on abundance of macrofauna that provide ecosystem services and need consideration when working towards sustainability.

VERTICAL DISTRIBUTION AND SPATIAL PATTERN OF FINE ROOT DENSITY IN COFFEE – BASED AGROFORESTRY SYSTEMS UNDER ORGANIC AND CONVENTIONAL INPUTS

&lt;p&gt;This research shows results on spatial changes of fine roots (&lt;em&gt;d&lt;/em&gt; &amp;lt; 2.0 mm) in two &lt;em&gt;Coffea arabica&lt;/em&gt;- shade tree associations: coffee shaded by a) &lt;em&gt;Abarema idiopoda &lt;/em&gt;(timber and nitrogen fixing tree), and b) &lt;em&gt;Terminalia amazonia &lt;/em&gt;(timber tree). These associations were submitted to organic and conventional inputs. In order to identify fine root vertical distribution and using soil cores, coffee and shade tree fine roots were quantified to 50 cm depth. A geostatistical approach was used to quantify the scale of spatial heterogeneity (aggregation patterns) of coffee and shade- tree fine root length density (RLD, cm cm&lt;sup&gt;-3&lt;/sup&gt;; 0- 20 cm soil depth). Results about vertical distribution demonstrated that in all the associations the coffee fine roots were concentrated in the upper 20 cm of soil&lt;em&gt;. &lt;/em&gt;The significant amount of coffee fine roots in the litter layer demonstrated the importance of including this layer for a real estimation of coffee fine roots in shaded coffee systems. The shade tree fine roots showed marked differences in their vertical distribution and affected the fine root density of coffee plants between 0- 50 cm soil depth; being more abundant when coffee is planted with &lt;em&gt;T. amazonia&lt;/em&gt;. The scale of spatial heterogeneity (aggregation patterns) for coffee RLD was longer in the organic plot than in the conventional plot for all of the coffee- tree associations. In the coffee- &lt;em&gt;T. amazonia&lt;/em&gt; association, the semivariogram of the coffee RLD under conventional management showed a spatial correlation at a relative short scale (3.5 m); however, in the organic plot, the semivariogram did not show spatial heterogeneity and exhibited a random pattern of coffee RLD at the scale examined. It is concluded that the type of management affects the pattern of spatial aggregation (spatial heterogeneity scale) of &lt;em&gt;C. arabica&lt;/em&gt; fine roots. Implying that the ability of coffee roots for the water and nutrient intake change spatially, either vertically or horizontally, depending on the accompanying shade- tree. According to the occupation of the fine roots within the layers of the soil to the depth studied, &lt;em&gt;T. amazonia&lt;/em&gt; seems to be the timber species recommended for the establishment of a coffee-based agroforestry system.&lt;/p&gt;

Conservation of ecosystem services does not secure the conservation of birds in a Peruvian shade coffee landscape

SummaryAgricultural intensification in shade coffee farms has strong impacts on the structure and diversity of the agroforest, with negative consequences for forest specialist birds, understorey insectivores and their associated ecosystem services. Utilising variable distance transect counts, we sampled the bird community in a multiple-certified yet changing shade coffee landscape in the Peruvian East Andean foothills, to evaluate bird functional diversity and to assess potential impacts of coffee production on avian ecosystem services. To account for incomplete detection, we also calculated expected species richness per functional group, and to evaluate the effect of future species losses, we derived reduced bird communities by subsampling our data using a Monte Carlo procedure. We compared the relative abundances of functional groups based on preferred diets in the observed, expected and reduced bird communities to global functional signatures of tropical bird assemblages of forest, agroforests and agriculture. The birds in the shade coffee landscape were predominantly birds of secondary and disturbed forest habitats, indicating, as expected, strong human impact on the forest structure. Yet, the diet signatures of the observed, expected and simulated bird communities were not significantly different from global diet signatures of forest and agroforest bird communities of mixed tropical landscapes. Our results suggest that avian ecological function can be conserved at bird community level despite intensive human ecosystem use and associated losses of forest specialist and other less resilient bird species. These results underscore that forest management strategies or certification audits focused solely at ecosystem services may be insufficient to support conservation of rare or threatened bird species and that shade coffee systems can in no way replace the role of protected natural forests.

Bird communities in sun and shade coffee farms in Kenya

Agricultural expansion to meet rising crop demand is one of the greatest threats to terrestrial biodiversity. Coffee, one of the most valuable trade items in tropical countries, can provide both economic livelihood and wildlife habitat. Previous work, conducted primarily on Neotropical coffee farms, indicates that birds are generally more abundant and diverse in farms with a canopy of shade trees, though regional variation exists. To date, few studies have examined birds on coffee farms in Africa, which contains 20% of the world’s coffee acreage. We studied differences in the bird communities between sun and shade monoculture coffee in central Kenya, and we examined effects of vegetation on bird abundance and diversity. Sun coffee had higher species richness and abundances of all major guilds (omnivores, insectivores, and granivores), and showed low community similarity to shade. Unlike findings from the Neotropics, canopy cover appeared to have a negative influence on all guilds, while understory volume of weeds increased bird abundance and species richness with a similar magnitude as canopy cover. These differences highlight the need for further studies in the general East Africa region with a wider variety of shade coffee systems.

Carbon Stocks in Organic Coffee Systems in Chiapas, Mexico

Agroforestry systems contribute to the maintenance of ecosystem functions, especially agrisilvicultural systems such as shade coffee systems. However, the role of organic crops to store carbon has been scarcely investigated. This study aimed to quantify carbon stocks in organic polyculture coffee plantations, non-organic polyculture plantations, and organic Inga spp.-shaded coffee systems in northern Chiapas, Mexico. Vegetation inventories were carried out in 1,000 and 100 m 2 circular plots from six agroforestry communities. Carbon stocks were estimated from living biomass and roots through allometric formulas; dead biomass and soil organic matter (0- 0.3 m- in depth) were collected, dried, weighted and processed for laboratory analysis. Firstly, results showed that living biomass contributed about 30% of total carbon; soil organic carbon particularly contributed between 56 and 70%; while dead organic matter represented between 3 and 5% of total carbon in the system. Organic polyculture coffee plantations stored significantly more carbon in soil (0.1-0.3 m in depth) and tree biomass than non-organic polyculture coffee plantations. These stocks were intermediate in organic Inga spp. - shaded coffee system. Secondly, dead organic matter was statistically similar between systems. Thus, organic polyculture coffee plantations, non-organic polyculture, and organic Inga spp.-shade system stored 194.7, 134.9, and 154.3 Mg C ha -1 of total carbon, respectively. In the same order, these systems stored in live aboveground biomass 57.5, 53.0, and 46.9 Mg C ha -1 , respectively. Dead organic matter had similar amounts of C stored in the three studied systems (6.3 Mg C ha -1 ). The amounts of total carbon stocks in organic coffee were higher than those reported for others in coffee plantations in Central America and, particularly, similar to some dry and semi-humid forests and other agrisilvicultural systems in Mexico. The results highlight the importance of coffee, especially organic coffee to provide the environmental function of carbon sequestration.

Shade tree diversity, carbon sequestration, and epiphyte presence in coffee agroecosystems: A decade of smallholder management in San Ramón, Nicaragua

Coffee smallholder management practices have received attention for their potential to conserve biodiversity and sequester carbon by maintaining structural complexity, high canopy diversity, and minimal external inputs. We conducted shade tree surveys on 95 1000m2 research plots over a 10-year period to identify patterns of shade tree density and diversity, epiphyte presence, and carbon stocks within smallholder shade coffee systems of northern Nicaragua. We also analyzed each of these parameters with respect to management by comparing collectively- and individually-managed farms. Our results indicate that the overall shade tree density has decreased over time (F=42.597, p<0.001), but that diversity remained constant. Carbon stocks in coffee systems also showed a decreasing trend over time (F=2.981, p=0.056), most likely due to the decreasing tree densities. Epiphytic plant presence increased over time despite decreased host tree densities, suggesting either a change in management or improved habitat conditions for epiphytes. Research plots on individually-managed coffee farms generally had higher shade tree densities than those on collectively managed farms (t=2.141, p=0.037), but we found no differences in shade tree species richness or carbon stocks (t=0.573, p=0.568). We conclude that smallholder coffee farmers continue to conserve both shade tree diversity and epiphyte communities.

Connecting sustainable agriculture and wildlife conservation: Does shade coffee provide habitat for mammals?

Shade coffee systems provide a refuge for biodiversity; however, research has been dominated by bird and insect studies with few studies that have focused on mammals living within coffee-dominated landscapes. Relative to other taxa studied, only 5% of the articles published on coffee and biodiversity pertain to mammals. We surveyed non-volant mammals, with an emphasis on small mammals, in 3 coffee-forest landscapes in Costa Rica with a particular focus on forest, shade coffee, and sun coffee habitats. Each of the 3 sites contained a 500-×500-m trap grid that was sampled in 4 sessions, totaling 46 sampling nights per site. This novel approach allowed us to compare mammal abundance and richness on both a plot level and meso-landscape scale (radius 25, 50, 100, 150, 200m). We made 976 captures (501 individuals) and detected 17 small and medium mammal species during the seven-month study period. The abundance and richness of small non-volant mammals found in the shade coffee was not significantly different that of forest habitats embedded and adjacent to coffee. Both forest and shade coffee had significantly more species and higher abundances than sun coffee habitats. Within habitats, at the plot level, higher amounts of canopy cover and lower strata vegetation (i.e., weeds, grasses, plants, and understory shrubs from 5cm–1m tall) significantly increased small mammal abundance and richness. Within coffee habitats (sun and shade), greater amounts of canopy cover were significantly associated with higher small mammal abundance and richness. At the meso-landscape scale, small mammal density and richness significantly decreased with increasing proportion of sun coffee within the landscape and increased as the amount of shade coffee increased. Furthermore, small mammals thrived in areas adjacent to forest patches and as the proportion of forested areas within the landscape increased. Our study indicates that while there is no substitute for native forest, shade coffee provides habitat for small non-volant mammals, particularly in comparison to sun coffee. Based on our findings, we recommend including shade trees, maintaining high amounts of canopy cover, and retaining lower strata vegetation (5cm–1m) within coffee farms. We also recommend preserving or reestablishing forested areas embedded within the coffee landscape to enhance small mammal diversity. Shade coffee shows promise as a conservation strategy to promote wildlife conservation and protect mammalian biodiversity.

Almacenamiento de carbono en arreglos agroforestales asociados con café (Coffea arabica) en el sur de Colombia

&lt;p align="left"&gt;Se calculó la cantidad de carbono almacenado en cuatro tipologías de sombra en sistemas cafeteros del sur de Colombia: Alta densidad de árboles con sombra diversificada (Alta.Dens), Guamo en alta densidad (Guam.Ad), Nogal en alta densidad (Nog.Ad), Plátano con baja diversidad (Plat. Bdiv), Sombra compleja diversificada (Com.Div), mediante el uso de ecuaciones alométricas para medición biomasa; el estudio se desarrolló entre Junio y Diciembre de 2012. Las tipologías con mayor tasa de almacenamiento de carbono fueron: Com.Div y Guam.Ad con 87,37 y 58,11 t ha-1 de C respectivamente. Las tipologías Alta.Dens y Guam.Ad presentaron menor tasa de almacenamiento de carbono. Se encontró relación entre el % de cobertura de las tipologías y el aumento en la acumulación de carbono; es decir, los sistemas con mayor diversificación presentaron mayores valores de acumulación de carbono.&lt;/p&gt;

Environmental and Habitat Drivers of Relative Abundance for a Suite ofAzteca-AttackingPseudacteonPhorid Flies

Phoridae (Diptera) have widespread impacts on insect communities by limiting host ant behavior. However, phorid-ant interactions may vary with habitat or environmental conditions. Three Pseudacteon species parasitize Azteca instabilis Fr. Smith, a common ant in coffee agroecosystems, and limit A. instabilis foraging, indirectly benefiting other insects. However, little is known about how phorid abundance, behavior, and effects change with environmental conditions. In shaded coffee systems, coffee (Coffea arabica L.) grows under a range of shade conditions and management changes affect species interactions. For example, Pseudacteon spp. more strongly limit A. instabilis foraging in low-shade coffee habitats. We sampled relative abundance of three phorid species around A. instabilis nests in three coffee habitats varying in shade management during dry and wet seasons. We measured canopy cover, tree richness, tree density, leaf litter depth, and number of nearby trees with A. instabilis to determine whether these habitat factors correlate with phorid abundance. P. laciniosus Brown was the most abundant phorid in both seasons. Phorid relative abundance did not differ by habitat, but did differ by season. P. laciniosus accounted for a higher proportion of phorids in the wet season (91.4%) than in the dry season (78.9%), and P. planidorsalis Brown accounted for a larger percent in the dry season (21.1%) than in the wet season (7.3%). Phorid composition did not differ with habitat type, and none of the measured environmental variables correlated with changes in phorid composition. Thus, phorids in coffee agroecosystems respond to large seasonal differences, but not differences between coffee habitats.

Socioeconomic benefits of shade trees in coffee production systems in Bonga and Yayuhurumu districts, southwestern Ethiopia: Farmers’ perceptions

Coffea Arabica is extensively cultivated by households under a variety of shade trees in southwestern Ethiopia. The main purpose of this study was to assess the overall farmers' perception on the benefits of shade trees in coffee production systems in southwestern part of Ethiopia. Semistructured questionnaires were administered to 100 smallscale coffee farmers. In-depth interviews were also made with 10 selected farmers from Bonga and Yayu-Hurumu districts study sites. Farmers’ perspectives were mostly comparable to the documented scientific facts with some noticeable differences. Among shade tree species legumes such as Albizia gummifera, Acacia abyssinica, Millettia ferruginea were highly favoured in that order. A significant number of the study subjects expressed an interest in the further propagation of the seedlings of the most favoured shade trees such as Albizia gummifera (95%), Acacia abyssinica (65%), Millettia ferruginea (55%) and Cordia africana (50%). The respondents strongly stated the serious problems associated with growing coffee without shade tree plants that included stunted growth which ultimately resulted in coffee yield reduction (97.3%) and quick wilting of coffee plants (93.6%). The majority of the respondents hassled other benefits of coffee shade trees such as firewood (96.4%) and honey production (92.7%) followed by improvement of soil fertility (79.1%) and reduction of soil erosion (78.2%). A significant number of farmers (39.1%) expressed their long experience of retaining legumes like Desmodium species in their coffee plots during weeding or clearing. Higher return values and better coffee attributes were generally assigned to shaded coffee systems particularly those dominated by tree legumes. The respondents had excellent knowledge on socioeconomic benefits of shade tree species. However, organic training is believed to minimize knowledge gaps on certain complex and/or unobservable ecosystem processes in the shaded coffee systems to boost the confidence of the farmers in supplying green commodities of premium prices on sustainable basis. Keywords : intercropping; leguminous plants; organic farming; shaded coffee systems