Hybrid coffee cultivars may enhance agroecosystem resilience to climate change

Anthropogenic climate change is predicted to cause shifts in temperature and precipitation patterns that will be detrimental for global agriculture. Developing comprehensive strategies for building climate resilient agroecosystems is critical for maintaining future crop production. Arabica coffee (Coffea arabica) is highly sensitive to the quantity and timing of precipitation, so alterations in precipitation patterns that are predicted under climate change are likely to be a major challenge for maintaining coffee agroecosystems. We assessed cultivar selection as a potential component of more resilient coffee agroecosystems by evaluating water stress responses among five Arabica coffee cultivars (clonal hybrids H10 and H1 and seedling lines Catuai 44, Catuai, and Villa Sarchi) using a precipitation reduction experiment in the highlands of Tarrazú, Costa Rica. During the first harvest (eighteen months after planting), plants under the rainout treatment had 211% greater total fruit weight and over 50% greater biomass than under the control treatment, potentially due to protection from unusually high rainfall during this period of our experiment. At the second harvest (thirty months after planting), after a year of more typical rainfall, plants under rainout still produced 66% more fruit by weight than under control. The magnitude of the responses varied among cultivars where, at the first harvest, H10 and H1 had approximately 92% and 81% greater fruit production and 18% and 22% greater biomass, respectively, and at the second harvest H10 had 60% more fruit production than the overall average. Thus, our findings suggest that the hybrid lines H10 and H1 are more resilient than the other cultivars to the stress of high soil moisture. Overall, our results indicate that stress due to higher than average rainfall could impair coffee plant growth and production, and that cultivar selection is likely to be an important tool for maintaining the viability of coffee production, and the resilience of global agroecosystems more generally, under climate change.

Coffee Agroecosystem in Mexico: Productive Culture between Tradition and Change

Objective: Understand the productive cultural dynamics that underlies coffee agroecosystems in the Sustainable Rural Development District 005 Fortín, Veracruz, Mexico. Methodology: A survey was applied designed with open and closed questions. Data sets were subjected to analysis of variance, Tukey tests and frequency tables. Results: The coffee agroecosystems in Mexico are complex systems that underlie a particular cultural dynamic expressing a way of conceiving the world, that influences not only on their life, but also on the reproduction of certain management practices whose logic goes beyond economics. The coffee activity is carried out largely by tradition (39 %), characterized by shade-grown Coffea arabica agroecosystems (100 %), with yields lower than 5.87 t ha-1. Limitations of the study/Implications: This is a case study in a specific area of the state of Veracruz, and the results express a local reality. Findings: Producers perform up to four extra-farm economic activities to supplement their family income; paradoxically, this has served as the basis to keep carrying out the coffee activity, thus reducing their economic vulnerability and facilitating the continuity of their production methods and livelihood.

Aboveground Carbon Storage in Coffee Agroecosystems: The Case of the Central Region of the State of Veracruz in Mexico

This study quantifies the aboveground C storage of coffee agroecosystems (AESs) present in the Xalapa–Coatepec region of the state of Veracruz, one of the most important coffee producing regions in Mexico. We identified and determined the spatial distribution of five different types of coffee AESs. Then, through the point-centered quarter method, we measured canopy coverage, total height, diameter at breast height and density of tree species at 160 randomly selected sampling sites. Using allometric models, we estimated the aboveground biomass and the stored aboveground C by tree species and type of AES; and finally, we scaled up our results at the regional level. We found out that the coffee AESs with the greatest and the lowest potential for storing aboveground C are coffee (Co) + talltrees (tree stratum mainly composed of species taller than 15 m) and Co + AcaciaInga (tree stratum mainly composed by Acacia pennatula), with a carbon density as 73.27 Mg C ha − 1 and 38.47 Mg C ha − 1 respectively. The 91.2% of the total aboveground C in the studied region is stored by two coffee AES types: Co + talltrees and Co + Inga (tree stratum composed by Inga sp.). The aboveground C storage potential of all five coffee AESs in the central region of Veracruz is 2.43 million Mg C with an average carbon density of 55.12 Mg C ha − 1 . These results assert that coffee AESs should be considered important C sinks that contribute to the adaptation and mitigation of climate change.

Impact of Nutritional Management on Available Mineral Nitrogen and Soil Quality Properties in Coffee Agroecosystems

Coffee crop management is guided by an approach of synthetic nitrogen fertilizers application in order to guarantee high production rates; however, this type of management increases soil degradation. A study was conducted in order to evaluate the impact of changing soil nutritional management from Chemical (NPK) to Organic (Farmyard Manure-FYM), and from Chemical (NPK) to Mixed (NPK + FYM) regarding soil quality properties and mineral nitrogen available in coffee agroecosystems; a multi-spatial analysis was carried out considering a unifactorial design; soil samples were taken from depths between 0.10 and 0.20 m in 42 plots; physical and chemical variables were measured (ammonium, nitrates, pH, organic matter, moisture, bulk density and texture). It was found that Chemical Management affects the physical and chemical properties of soil quality (organic matter, humidity, bulk density, and pH), resulting in significant differences (p < 0.05) comparing to Mixed and Organic Management. The lowest level of organic matter was found under chemical management, being of 3% and increasing up to 4.41% under mixed management. Mineral nitrogen availability in the form of ammonium, was not affected by nutritional management. A higher concentration of nitrate was found under Mixed Management (105.02 mg NO3 kg−1), presenting significant differences (p < 0.05) against Chemical and Organic. There was no significant difference between Organic and Chemical Management. The study allowed us to determine that, through coffee organic nutritional management, it is possible to keep suitable soil quality conditions in order to reduce soil degradation, and to keep mineral nitrogen available for the development of coffee plants.

Effect of ecological and conventional managements on soil enzymatic activities in coffee agroecosystems

ABSTRACT Understanding the impacts of agricultural practices on soil quality indicators, such as enzymatic activities, is of great importance, in order to advance in their diagnosis and sustainable management. This study aimed to evaluate the effect of ecological and conventional agricultural managements on enzymatic activities of a soil under coffee agroecosystems. The enzymatic activities were associated with the biogeochemical cycles of nitrogen (urease and protease), phosphorus (acid and alkaline phosphatase) and carbon (β-glucosidase), during the rainy and dry seasons. Physical-chemical soil proprieties were also assessed and related to resilience scores linked to the climatic variability reported for the areas under study. The activities of urease, alkaline and acid phosphatase and ß-glucosidase were statistically higher in ecological agroecosystems than in conventional ones. This may be attributed to the greater application of organic waste in the ecological environment, as well as to the absence of pesticides and synthetic fertilizers, which allow better conditions for the microbial activity. The resilience scores to the climate variability that showed the highest correlations with the assessed enzymatic activities were: the farmers' knowledge on soil microorganisms, non-use of pesticides and synthetic fertilizers and non-dependence on external supplies. It was concluded that the enzymatic activities are modified by the management systems, being specifically favored by the ecological management. This agroecosystem, in the long term, ensures an efficient use of the soil resources, with a lower degradation and contamination.