# Towards Climate Smart Farming--A Reference Architecture for Integrated Farming Systems
## 1 Introduction  
Starvation is one of the biggest threats we are facing as humanity in the 21 st century. The global demand for food is increasing, with recent studies forecasting that the global population will reach 9.5 billion people by 2050 [1], and more than 80% of available land is already cultivated [2]. Global demand for farming products is expected to increase by 70% for food production [3] and double for livestock products by 2050 [4]. However, agricultural production is strongly affected by the changes in climate conditions, such as rising temperatures [5], changing rainfall regimes [6] and variations in the frequency and intensity of extreme climatic events such as floods and droughs [7]. The estimated impacts of the climate change indicates that the yield loss could be up to 35% for rice, 20% for wheat, 50% for sorghum, 13% for barley and 60% for maize [8], and livestock production will be also negatively affected [4]. Both farmers and breeders need to find efficient and affordable methods in order to strengthen the resilience of agriculture and livestock farming against climate change. Theconcept of Climate-Smart Agriculture (CSA) reflects an ambition to improve the resilience of agricultural systems against climate change [9; 10; 11]. The Food and Agriculture Organization (FAO) of the United Nations defines CSA as agriculture that enhances productivity, improves resilience, reduces greenhouse gases (GHG) and facilitates the achievement of national food security and development goals [9]. The CSA includes both traditional and innovative approaches; and technologies that promote agricultural productivity, increase the stability at the farm level and foster the sustainability of the relevant value chains [11]. A system that adopts the concept of CSA is expected to increase its resilience against fluctuating climate conditions and therefore offer increased food production in the face of a changing climate and increased climate variability, while improving nutritional outcomes and reducing the carbon cost of farming and its contribution to GHG emissions [12; 13; 14; 15]. It includes three major pillars: (a) increasing agricultural productivity; (b) increasing adaptive capacity at multiple scales (from farm to nation); and (c) reducing greenhouse gas emissions [12]. While there is a consensus on the potential of the CSA to support global food and nutritional security in less-favored conditions [11; 12; 13], CSA scholars have different perspectives when approaching the scaling of CSA options. Integrated systems can combine crop production, livestock and forestry, supporting the production of at least three types of product from the same land area over a defined period [16; 17; 18]. These systems, based on inter-cropping, succession and/or rotation, can optimize the biological cycling of nutrients between plants and animals, and maintain long-term soil fertility [19; 20; 21]. According to the FAO, Mixed Farming Systems (MFS) are defined as farming systems managed by households and/or enterprises where crop cultivation and livestock rearing together form integrated components of a single farming system. MFS offer a lot of advantages, such as efficient use of resources by using crops and grassland to feed animals and fertilize their fields with manure from the animals, complementarities between crops and livestock and a flexibility that allows the adjustment of crop/livestock ratios in anticipation of risks, opportunities and needs [19; 22; 23]. Such context-relevant integration of crops and animals in the same system appears to support a biological, ecological and economic sustainability in the global food production chain [17; 18; 23]. Nevertheless, MFS is not a universal panacea. The economic results of MFS are not as optimal as those of dedicated systems, especially considering the remuneration of labor.