This market has expanded rapidly in the past 20 years, with estimates of total retail specialty coffee sales—excluding Walmart—continuing to increase in the past decade . The specialty coffee market supports a distinct value chain. By definition, specialty coffees distinguish themselves from bulk coffee on the basis of a variety of factors that include quality , sustainability, and closer relationships with growers . Within the specialty coffee market, there are several types of certification for sustainability; the fair trade label is focused on the trade relationships, and organic requires soil conservation and prohibition of agrochemicals and genetically modified crops, among other criteria . Smithsonian’s Bird Friendly certification program has the highest agroenvironmental standards, requiring organic certification and more than 10 species of shade trees, as well as guidelines to conserve soil and water. Rainforest Alliance certified, UTZ certified, and fair trade also have several agroenvironmental standards restricting the use of many of the most toxic pesticides and herbicides, although synthetic fertilizers and some pesticides, fungicides, and herbicides are permitted. A trend that has continued since the 1990s is the significant rise in the quantity of coffee with one or more such ecolabel. It is estimated that more than 10% of the coffees sold in 2007 carried at least one sustainability certification, and it is expected that this percentage will continue to increase rapidly .

In addition to the certifications previously mentioned, firms, nonprofit organizations, square plastic pot and even governments continue to partner to generate an expanding number of different labels and sustainable coffee initiatives. Several key examples include the Common Code for the Coffee Community Association and two initiatives started by large coffee companies that do roasting and retailing, Starbucks’s Coffee and Farmer Equity Practices and Nestlé’s Nespresso AAAA Sustainable Quality Program. These latter two programs function by setting social and environmental criteria for certification and have grown rapidly in the past decade, with more than 160 million pounds of coffee certified in 2006 alone . A closer look at coffee profits and farmer livelihoods reveals that fair trade and organic certifications are able to provide a number of benefits to smallholder farmers, although livelihood challenges persist . For example, farmers who participate in cooperatives connected to fair trade certification often have more access to credit and technical support and often receive higher prices for their coffee, buffering their exposure to falling coffee commodity prices and diminishing the negative consequences of unexpected challenges, such as food shortages, hurricanes, and earthquakes . However, fair trade certification does not necessarily improve access to food through purchasing or production . Furthermore, although certifications are often associated with higher coffee prices, the small volumes sold and additional certification costs often counterbalance added income at the household level, especially because the real price premiums delivered to farmers have declined during the past decades . This suggests that major changes are required to provide a strong incentive for sustainable coffee management through the certification processes.Shaded coffee plantations are increasingly valued for their contributions to biodiversity conservation and the provisioning of ecosystem services . Since the 1990s, shade coffee has been noted for its contributions to conserving plant, arthropod, bird, bat, and nonvolant mammal diversity .

More recent studies have documented patterns of bird, ant, and tree biodiversity declines, specifically in response to decreasing vegetation cover and increasing management intensity . Biodiversity declines within coffee systems are of particular concern, given that ecosystem services such as pollination, pest control, erosion control, watershed management, and carbon sequestration are worth billions annually and are largely a function of biodiversity levels . Therefore, as a whole, ecosystem services tend to decline as forests are converted to shade coffee and as shade coffee is converted to low-shade coffee systems . According to our review, unique ecosystems across varying coffee vegetation management styles have been directly measured in more than 70 studies, including pollination , pest control , climate regulation , and nutrient cycling . Although distinct methodologies and methods of measuring response variables complicate meta-analyses for each unique ecosystem service, we found positive effects of shade on ecosystem services in approximately 58% of the pollination studies, 60% of the pest control studies, 100% of the climate regulation studies, and 93% of the nutrient cycling studies . Specifically, vegetation complexity at the canopy level can lead to lower weed densities , and because many shade trees fix nitrogen , they can increase the nutrient content of soils . Scant-shade coffee systems sequester an additional 53–55 tons of carbon per ha in above ground biomass compared with unshaded coffee monocultures . In Mexico, Soto-Pinto and colleagues found that Inga-shaded organic coffee maintained carbon above ground and in the soil to an extent equal to that of nearby forests, and traditional polyculture coffee maintained more carbon than all other examined land-use types. If we consider that scant-shade systems sequester an additional 53 tons of carbon per ha more than unshaded systems do , the conversion of even 10% of unshaded coffee systems to even scant-shade cover would result in 1.6 billion additional tons of above ground sequestered carbon.

Many organisms aid in pest control on shaded farms. Ants and spiders, for example, reduce the damage caused by the coffee berry borer, Hypothenemus hampei Ferrari , and the coffee leaf miner, Leucopteracoffeella Guer. . Birds and bats predate on arthropods in shaded coffee plantations. Predation services by birds and bats have been documented to improve coffee yields by 1%–14%, which amounts to values that exceeded $44–$105 per ha per year and $75–$310 per ha per year for farmers . Pollinators are also crucial for coffee production because both commercial species of coffee benefit from pollinator visits and pollinator diversity . In Costa Rica, increased fruit set due to enhanced insect pollination at a per bush level improved coffee yields by more than 20% in one 1100-ha farm, worth an estimated $62,000 . Again, if 10% of the sun coffee systems were converted to scant or diverse shade and if pest control services in these shaded systems continued to be valued at $75 per ha and pollination services at $56 per ha , the additional pest control and pollination contributions provided could exceed $2.3 billion and $1.7 billion, respectively. Overall, these studies highlight the great potential for increased carbon sequestration, pest control, and pollination services within shade coffee systems. For example, migratory birds often use shade coffee farms as a corridor when moving between temperate and tropical regions . Pollinators, such as butterflies and native bees , can migrate between forest fragments and shade coffee farms. As a result, native trees support pollinators that are crucial during the coffee bloom and are able to maintain reproduction and gene flow processes for plants across shade coffee systems . Unlike sun coffee systems, which do not provide pollinators with resources throughout the year and are less permeable to dispersing organisms , shade coffee farms can promote pollinator populations and serve as corridors for organisms moving regionally between forest fragments. The importance of connectivity between coffee and protected areas is tremendous, given the overlap and proximity of biodiversity hotspots and coffee-growing regions and the importance of shaded coffee in the face of global climate change. Coffee farms are often located adjacent to protected areas; in many countries, including El Salvador, Guatemala, and Costa Rica, more than 30% of the area surrounding coffee regions falls within protected areas . Because organisms such as birds, bats, and bees in tropical habitats often disperse across short distances, the proximity of coffee farms to protected areas magnifies the role of coffee in serving as an important biological corridor. Shaded systems have also been identified as part of the remedy for confronting harsh new environments in coffee regions that result from climate change . Climatological models predict that the Caribbean and Central America will experience general drying as well as stronger later-season hurricanes . Hurricanes can result in major economic losses for coffee farmers, but farms with more-complex vegetation experience significantly fewer post hurricane landslides . Coffee farmers, 25 liter pot realizing the enhanced risk in less-shaded fields, have engaged in post hurricane mitigation focused on increasing the planting of more shade trees within their coffee fields . Shaded and diversified coffee farms also provide greater climate-regulating services, with potential impacts on coffee berry development and overall yield . Coffee depends on seasonal rainfall for flowering and leaf photosynthesis; therefore, coffee growth rates and yields are highest in specific precipitation and temperature ranges .

We spatially quantified the change in coffee suitability in Mesoamerica using the same methodology as that described in Läderach and colleagues for Nicaragua and in Schroth and colleagues for Chiapas, in Mexico. We used WorldClim as the current climate database, the most representative Global Climate Models of the Fourth Assessment Report for the Special Report on Emission Scenarios A2a emission scenario, and existing data on coffee suitability in Central America as input data for the Maxent niche model. The Maxent model predicts spatially current climatically suitable coffee-growing areas on the basis of presence data and the climate at these locations. The established relationship between the current climate and the suitability index are then projected into the future. The model is based on the assumption that, in the future, the same climatic factors will drive coffee growth as do currently; therefore, the model does not take into account any adaptation strategies by means of germplasm or other improvements. We show that there is an important decrease in the suitability of coffee-producing areas by 2050 . Coffee suitability in this context refers to areas that are climatically suitable to grow coffee, such that values below zero indicate areas less suitable than current conditions and values above zero indicate areas more suitable than current conditions. Specifically, the average temperature is predicted to increase by 2–2.5 degrees Celsius by 2050, and, because coffee is very sensitive to changes in temperature, coffee planting will need to move upslope by 300–400 m in order to compensate for the increase in temperature . The shift in elevation will increase the pressure on forests and the environmental benefits they provide to downstream communities.When synthesizing research on global coffee distribution and cultivation practices, livelihoods, biodiversity, ecosystem services, and climate resilience, it becomes clear that distribution and cultivation practices are heterogeneous and are largely a function of local and global market forces, incentives for intensification, and price premiums for diversification or improved livelihoods. Traditional shade systems constitute less than 24% of the coffee production areas surveyed in 2010, and the coffee expansion in the past two decades has been typified by intensive unshaded practices. Millions of coffee farmers continue to struggle for survival, despite the production of high-quality coffees and the generation of crucial ecosystem services . Although some ecosystem services are well known to coffee farmers , many others remain obscure to external agencies because of the indirect nature of their services and the potential for interaction . Henry and colleagues examined interactions between plant biodiversity, regulating , and provisioning ecosystem services in Kenya and found that increasing carbon sequestration by adding more trees could have a negative effect on food production. In another example, Méndez and colleagues showed that a higher density and diversity of shade trees resulted in a higher potential for provisioning services , with greater profits for farmers but with lower coffee yields. Because coffee yields are typically assessed independently of yield from timber, other crops, or ecosystem services, it may be difficult for governments and conservation institutes to weigh the benefits of diversified farming approaches. We propose three main focal research and development areas that could advance ecosystem service provision and sustainable livelihoods in coffee systems.Although certification is a common default approach used to integrate sustainable agriculture with worker livelihoods, the certification approach is challenged by the limited nature of the certifications available and the organizational and financial costs of certification. The existing certifications have unique ecological standards, offer distinct economic incentives to different agents , and also differ in the price premium provided . As a result, farms that provide substantial ecosystem services but do not qualify for existing certifications are left out, and those that do qualify often face high costs of inspection and certification. For example, although organic and fair trade certification may raise coffee export prices , these returns may not cover the additional costs associated with maintenance and certification .