The Sahara Was Once Green

 Syntropic Agriculture  | Joshua Sparkes

Topological Scaling Laws and the Mathematics of Evolution

 Nigel Goldenfeld

Agrobiodiversity, community participation and landscapes in agroecology

Tomás Enrique León-Sicard, Diego Griffon and Massimo De Marchi

The current model of conventional agriculture on the planet, originated in the so-called “Green Revolution” (GR), has generated positive and negative effects during its more than 80 years of application, starting in the 1940s. Among the negative effects are the accelerated loss of biodiversity and agrobiodiversity. 

Different alternative farming systems propose managing the agrobiodiversity of agroecosystems (farms) to face many of the problems generated on monoculture farms (e.g., soil and genetic erosion, emergence of genetic resistance in pests and weeds, as well as public health problems associated with the use of agrochemicals), which are characteristic of the current conventional model (Vandermeer and Perfecto, 2005; Pollan, 2007). 

Many positive effects are attributed to diverse crop fields. To name just a few, at the ecosystem level, beneficial effects have been proven in the preservation of the habitat for beneficial insects (pollinators, natural enemies of pests), reduction in GHG emissions, protection of soil and water, zero poisoning of human beings and nonhumans, reduction of pollutants and hazardous waste, and climate stability (Altieri, 1996; Nicholls, 2002; Letourneau et al., 2011; Gliessman, 2014; Vandermeer and Perfecto, 2018). 

Agrobiodiversity is the very foundation upon which agroecology is built. It provides the mechanisms that allow agroecosystems to be managed sustainably through a set of beneficial interactions between their elements (e.g., mutualisms that occur in pollination, mycorrhizae or in crop associations).

The elements that constitute an agroecosystem are directly related to its main agroecological structure (MAS), which refers to the way in which the different sectors, patches, live fences, and vegetation corridors are arranged (spatial configuration), mixed or not with crop areas, grasslands, or agroforestry systems inside the farms and in their close surroundings. An agroecosystem structure is historically constructed by farmers because of innumerable cultural variables (symbolic, economic, social, political, and technological), in conjunction with environmental processes and its evolution configures agroecosystem matrices in the landscape (León-Sicard et al., 2018; Quintero et al., 2022). In this context,the use of the MAS approach, paired with other agroecological tools, such as the farmer-to-farmer methodology and participatory action research, can be employed as inputs into the decision- making process necessary for sustainable landscape management and conservation of agrobiodiversity in rural environments (Holt- Gimenez, 2006; Guzmán et al., 2012).

Most of the world’s industrial agricultural landscapes present matrices of farms with very poorly developed agroecological structures that respond to the simplification characteristic of conventional agriculture, which has eliminated forests, corridors, patches, and live fences to make way for extensive monocultures (Vandermeer and Perfecto, 2005; León-Sicard et al., 2018). This simplification has also been the product of pesticides used to eliminate biological competitors to the main crop and to eliminate agents considered pathogenic or harmful.

In contrast, ecological- or agroecological-based agriculture proposes to maintain and reinforce agrobiodiversity in all its manifestations, both on and off the farm, as a way of achieving greater resilience, equity, autonomy, stability, and productivity through the multiple interactions that it fosters. Agroecological landscapes, therefore, will have agroecosystem matrices with more developed structures and functions favorable to agrobiodiversity.

These interactions between the different elements of agrobiodiversity are not restricted to the biological realm but are rather intricately woven into the fabric of socio-ecological systems.

These latter systems, whose central protagonists are the farmers and their cultural actions, are clearly the beneficiaries of the interactions (services) but are also responsible, in multiple ways, for the maintenance of this biodiversity. It is important to highlight that the interactions that articulate these systems manifest themselves on different scales, and in this Research Topic, we will find works that clearly show this fact.

This Research Topic collected 13 articles involving 46 authors from 36 research institutions in 14 countries on four continents. The case studies dealing with different levels of agrobiodiversity (from crop to landscape) are based in seven countries: China, Italy, Nigeria, Colombia, Venezuela, Chile, and Uruguay.

This Research Topic includes articles that address the effects of climate change on the soil fauna of agroecosystems (Gao et al.) and how the soil microbiome can be used to adapt crops to the new climate context (Pino and Griffon). Innovative management approaches link silvopasture systems with ecosystem restoration (Durana et al.). Other contributions investigate the needs of the end users of this biodiversity (Tchokponhoué et al.), the role of entrepreneurial identity in shaping attitudes toward sustainability (Rossi et al.), and studies that address people’s ecological, esthetic, and medicinal knowledge about the plants in their crops and communities (Kolze et al.; Monagas and Trujillo). Other articles address, at a larger spatial scale, the criteria for establishing community gardens in urban environments (Codato et al.), the precautions that must be taken in terms of conservation before undertaking agricultural expansions (González-Orozco et al.), or the strategic role of managing the relations among agroecosystems and landscapes to build resilient nature matrixes (Puppo et al.; Rettore et al.) The work of Acevedo-Osorio et al. proposed an index of agroecological functionality at the landscape level in Colombia, and Rojas et al. measured the degree of connectivity of agroecosystems with the landscape, using the MAS method, in a Mediterranean environment in Chile.

In all of these works, it is clear that agrobiodiversity, through the multiple functions it fulfills, articulates, and keeps these socio- ecological systems viable. In this way, we can understand it as the glue, often invisible to our eyes, that holds these systems together and, in doing so, makes our own lives possible.

The growing competition of labels for innovative approaches to sustainable agriculture should be analyzed using the elements of agroecology (FAO, 2019), with special attention to agrobiodiversity and its plural connections with food culture and traditions, circular and solidarity economy, and responsible governance (Tittonell et al., 2022).

Agroecology, as a meeting point of plural paths between science, movements, practices, and symbolic tissues, indagates the participatory processes of the construction of agrobiodiversity, food sovereignty, and biocultural diversity (Pimbert, 2018) from a long-term perspective, weaving, often not explicitly, practices of circulation and the construction of complex nested agroecosystems and landscapes. 

From an emancipatory perspective (Giraldo and Rosset, 2023), the reflections and practices deal with territorial and food policies that transform structures, do not reproduce exclusion, and cultivate autonomy based on the co-construction of knowledge at a higher level of integration among crops, animal and vegetal species, landscapes, and biomes. Agroecology has the task of revealing the ontology of agriculture itself, deepening the meanings of being, living, and remaining in the places of communities that build and transfer over time, co-evolving multiscalar matrices of nature (Giraldo, 2022).

https://n9.cl/jkfns

Topology Shapes Dynamics of Higher-order Networks

Ginestra Bianconi

 

El Holoceno, ese período de estabilidad climática que nos ha permitido florecer como especie y construir civilizaciones, puede pasar a ser un recuerdo. El Holoceno representa un intervalo de gracia, que nos ha permitido cultivar los alimentos que sustentan nuestra vida.  Es un susurro de estabilidad en el caos del tiempo geológico. Comprender las dinámicas del Holoceno es fundamental para valorar la fragilidad de nuestro planeta y tomar medidas para asegurar un futuro sostenible. Sin embargo, esta ventana de oportunidad se está cerrando, dejando tras de sí un profundo anhelo por un pasado que ya no volverá.

As scientific understanding has grown, so our world has become dehumanized. Man feels himself isolated in the cosmos, because he is no longer involved in nature and has lost his emotional “unconscious identity” with natural phenomena. These have slowly lost their symbolic implications. Thunder is no longer the voice of an angry god, nor is lightning his avenging missile. No river contains a spirit, no tree is the life principle of a man, no snake the embodiment of wisdom, no mountain cave the home of a great demon. No voices now speak to man from stones, plants, and animals, nor does he speak to them believing they can hear. His contact with nature has gone, and with it has gone the profound emotional energy that this symbolic connection supplied. 

C.G. Jung. 1969. Man and his symbols. Dell

 Webinar: Agroecology, Organic, Regenerative, Nature-based 

The Tipping Points of Climate Change — and Where We Stand 

Johan Rockström

Population Theory for the Hologenome and the Assembly of Holobionts 

by Professor Joan Roughgarden