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Chinampas in the news - Mexico

Here is an interesting article about the current state of Mexico’s chinampas. For more articles on Chinampas and related agriculture / land management systems from this site search “chinampa” in the right-hand side bar (or click link). Here is a link to the original article quoted below.

Mexico’s Chinampas – Wetlands Turned into Gardens – Fight Extinction

By Emilio Godoy

Edited by Estrella Gutiérrez/Translated by Stephanie Wildes

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A farmer transports his freshly harvested crops from his chinampa – a rectangular garden on land reclaimed from the wetlands of Mexico City – along a canal in Xochimilco. But this age-old Aztec technique used to feed the local population is threatened by the encroaching city and by pollution. Credit: Emilio Godoy/IPS

XOCHIMILCO, Mexico , Feb 27 2016 (IPS) – David Jiménez grows two kinds of lettuce and other fresh produce on his “chinampa” or artificial island just under one hectare in size in San Gregorio Atlapulco, on the south side of Mexico City.

“We can get five or six harvests a year. Lettuce can grow in 30 days,” Jiménez, the president of the six-member La Casa de la Chinampa cooperative, told IPS with evident enthusiasm. The cooperative operates in Xochimilco, one of Mexico City’s 16 boroughs.

The ejido – land held in common by the inhabitants of a village and farmed cooperatively or individually – where Jiménez has his farm covers 800 hectares, and is home to 800 farmers who mainly grow vegetables. Half of the ejido is made up of chinampas.

The system of chinampas dates back to the Aztecs, long before the arrival of the Spanish conquistadors in the 15th century. The technique creates small, rectangular gardens reclaimed from Mexico City’s marshy lakebed by piling up soil on a mat of sticks, using wattle as fencing and willow trees at the corners to secure the bed.

The chinampas are rich in muck and decaying vegetation, which provide nutrients for the crops, while the ditches between them give the plants continuous access to water. As a result, the vegetables grown there are especially rich in nutrients.

The chinampas, which help feed the 21 million people who live in Greater Mexico City, are in the boroughs of Milpa Alta, Tláhuac and Xochimilco.

Worked by some 5,000 farmers, the chinampas cover a total of 750 hectares. The system is profitable, because they produce a combined total of around 80 tons a day of vegetables.

Each head of lettuce fetches 10 cents of a dollar, Jiménez said, as he tended to a row of lettuce.

The chinampas or “floating gardens” produce spinach, chard, radishes, parsley, coriander, cauliflower, celery, mint, chives, rosemary, lettuce and purslane or pigweed. Visitors to the area walk along paths that take them across a green carpet segmented into rectangles of crops and divided by the ditches of water they depend on to grow.

The drought-resistant system uses less water than traditional irrigation and produces fish, vegetables, flowers and medicinal herbs.

Studies also show that the chinampas repel pests, are more productive than conventional agricultural systems, and produce biomass. The technique is completely sustainable, retaining moisture and regulating the microclimate in the area.

 

David Jiménez, a local farmer, next to medicinal herbs grown on his land in San Gregorio de Atlapulco in the Mexico City borough of Xochimilco, where chinampas continue to survive – an age-old Aztec technique that creates farmland out of the local wetlands. Credit: Emilio Godoy/IPS

Ricardo Rodríguez, founder and director of the company De la Chinampa a tu Mesa (“from the chinampa to your table”), came up with a way to link traditional production techniques with new technologies, by marketing the vegetables grown on the chinampas over social networks.

He picks up fresh produce in the Cuemanco natural area in Xochimilco, signs up customers on his web page, processes the purchases, and distributes the orders to the customers’ homes.

“We help generate demand, which motivates them to keep farming. And this helps restore the chinampas. The market is starting to recognise the value of the chinampas,” Rodríguez told IPS.

The entrepreneur works with 22 “chinamperos” or chinampa farmers who grow broccoli, spinach, beets, radishes and other crops on approximately 15 hectares. He delivers some eight orders a day, weighing eight kg on average. His 450 registered customers include stores and restaurants that sell organic food.

Xochimilco, which is home to more than 415,000 people on some 125 sq km, was named a World Heritage Site by the United Nations Educational, Scientific and Cultural Organisation (UNESCO) in 1987.

In addition, the Ejidos de Xochimilco and San Gregorio Atlapulco Lake System have been on the Ramsar ConventionList of Wetlands of International Importance since 2004.

The U.N. Food and Agriculture Organisation (FAO) selected the chinampas as a Globally Important Agricultural Heritage System (GIAHS), because they preserve agricultural biodiversity, help farmers adapt to climate change, bolster food security and reduce poverty.

Marco Covarrubias, the head of the Gastronomy Centre at the private Claustro de Sor Juana University based in Mexico City, stresses the importance of the chinampas in terms of food production.

“The advantage is that they are in permanent contact with water, which unlike in other systems is not used to irrigate but is absorbed by the plants,” he told IPS. “And they have added nutritional value because a large part of the chinampas is free of pesticides and other agrochemicals.”

Urban sprawl and expanding slums, the use of pesticides, climate change, excessive use of groundwater, and neglect have all contributed to the destruction of the chinampas, says a study by the Natural and Cultural Heritage of Humanity Zone Authority (AZP) in Xochimilco, Tláhuac and Milpa Alta.

The AZP, created in 2014, is in charge of managing the preservation of this special ecosystem, in order to maintain the UNESCO and Ramsar Convention designations.

“Any effort to protect the area must take into account the local farmers and the cultural environment surrounding the chinampas. This is a culture that is not really appreciated, the restoration plans haven’t been carried out,” said Jiménez.

His cooperative decided to create a model farm on two hectares of their land, to show visitors the benefits of the chinampas.

And on Feb. 22, it launched a programme in local schools, which includes a virtual tour of the chinampas. With some 6,400 dollars in public funds, the idea is to raise awareness among 6,000 students in primary and secondary schools in Xochimilco.

The environmental authority is facing cuts, which have hurt its efforts to protect the region. Its budget shrank from 700,000 dollars in 2015 to 400,000 dollars this year. Since 2013, the AZP has supported 174 environmental and cultural improvement projects, but there is no clear information about the specific impact on the chinampas.

In March 2014, the French Global Environment Facility donated 1.65 million dollars for the conservation of the area.

In an October 2014 report, “Rehabilitation of the chinampera network and the Xochimilco native species habitat,” the Biology Institute of the National Autonomous University of Mexico said restoration of the chinampas should be a priority, because of their ecological, economic and social importance.

It recommended promoting the concept of chinampa-nature reserve, “because this represents multiple benefits for improving water conditions while giving a boost to sustainable productive activities as a strategy to prevent encroachment by urban sprawl.”

Covarrubias, meanwhile, said “Greater attention should be paid to the chinampera zone; it should be studied as an area of extremely high production potential, and a public policy should be created to link people who live in, and make a living from, the chinampas, with direct buyers.”

Since 2014, his university has organised the La Chinampería programme, to hook up local farmers and buyers. And this year it is carrying out another applied research plan to foment value chains, with the participation of 15 chinampa farmers.

“Awareness-raising programmes are needed for their descendants to start to recuperate the chinampas, improve the cleaning system, and acknowledge the farmers,” said Rodríguez, the entrepreneur, who organises “consciousness-raising tours” on the role of the chinampas in food security and the importance of small-scale local agriculture.

He wants to create a market of producers in Cuemanco, generate a label for goods produced in Xochimilco, to boost the prices of local products, and set up a collection centre for the products.

Edited by Estrella Gutiérrez/Translated by Stephanie Wildes

Plants Are Better at Complex Decision-Making Than We Ever Realized

We know that plants can learn, and make decisions, and we now have a new level of insight into the decision-making process plants go through when put under pressure, vying with competitors for limited access to sunlight.

It turns out that plants can adapt to the size and strength of their nearby neighbors, deciding how best to survive considering what's happening around them, according to a new study. Read the full paper Decision-making in plants under competition at Nature.com.

Abstract

Plants can plastically respond to light competition in three strategies, comprising vertical growth, which promotes competitive dominance; shade tolerance, which maximizes performance under shade; or lateral growth, which offers avoidance of competition. Here, we test the hypothesis that plants can ‘choose’ between these responses, according to their abilities to competitively overcome their neighbors. We study this hypothesis in the clonal plant Potentilla reptans using an experimental setup that simulates both the height and density of neighbors, thus presenting plants with different light-competition scenarios. Potentilla reptans exhibit the highest vertical growth under simulated short-dense neighbors, highest specific leaf area (leaf area/dry mass) under tall-dense neighbors, and tend to increase total stolon length under tall-sparse neighbors. These responses suggest shifts between ‘confrontational’ vertical growth, shade tolerance and lateral-avoidance, respectively, and provide evidence that plants adopt one of several alternative plastic responses in a way that optimally corresponds to prevailing light-competition scenarios.

Source: Nature.com

Mapping the first family tree for tropical forests

More than 100 researchers have collaborated to classify the world's tropical forests according to their evolutionary history, a process that will help researchers predict the resilience or susceptibility of different forests to global environmental changes.

The results, culled from almost 1 million different tree samples from 15,000 tree species, have uncovered a shared ancestry between tropical forests thousands of miles apart and previously believed to be unrelated. Published this week in the Proceedings of the National Academy of Sciences, the study describes an international, grassroots effort to collect and analyze data from more than 400 geographic coordinates across the tropics, a region that comprises 40 percent of the Earth's surface.

The study was led by Ferry Slik, an associate professor at the Universiti Brunei Darussalam in Brunei. Janet Franklin, a distinguished professor of biogeography at the University of California, Riverside, coordinated the interpretation and reporting of the data, which is publicly available as an open access article.

Franklin said the new classification scheme's value comes from the inclusion of ancestral information about the tree samples (gleaned from DNA analyses), rather than the "snapshot" of tree biodiversity that is obtained from recording a plant's species.

"When ecologists study biodiversity, they look at the present day by identifying the range of species in a particular forest. However, without going deeper into a plant's history by looking at its family tree, each species is considered separate and unrelated," Franklin said. "By adding the evolutionary relationships between species, however, we suddenly have a measure of how similar species are to each other. This means that we were able to do a much more detailed and realistic comparison between forest sites than previously possible."

The study revealed five major tropical forest regions: Indo-Pacific, Subtropical, African, American, and Dry Forests, which are found at the boundaries between tropical and dry climates.

The study also showed the evolutionary relationships between the forests. One surprising finding was that tropical forests in Africa and South America are closely related, with most of the differences between them occurring within the last 100 million years.

More information: J. W. Ferry Slik el al., "Phylogenetic classification of the world's tropical forests," PNAS (2018). www.pnas.org/cgi/doi/10.1073/pnas.1714977115 

Journal reference: Proceedings of the National Academy of Sciences  

Provided by: University of California - Riverside 

2,000 years ago, people domesticated these plants. Now they’re wild weeds. What happened?

"Adventurers and archaeologists have spent centuries searching for lost cities in the Americas. But over the past decade, they’ve started finding something else: lost farms.

Over 2,000 years ago in North America, indigenous people domesticated plants that are now part of our everyday diets, such as squashes and sunflowers. But they also bred crops that have since returned to the wild. These include erect knotweed (not to be confused with its invasive cousin, Asian knotweed), goosefoot, little barley, marsh elder, and maygrass. We haven’t simply lost a few plant strains: an entire cuisine with its own kinds of flavors and baked goods has simply disappeared.

By studying lost crops, archaeologists learn about everyday life in the ancient Woodland culture of the Americas, including how people ate plants that we call weeds today. But these plants also give us a window on social networks. Scientists can track the spread of cultivated seeds from one tiny settlement to the next in the vast region that would one day be known as the United States. This reveals which groups were connected culturally and how they formed alliances through food and farming."

Read full article at ArsTechnica: Hunting for the ancient lost farms of North America

Is Amazonian tree biodiversity / species distribution a product of past landscape domestication?

News of recent studies has revealed that an estimated 390 billion trees are growing in Amazonia today, consisting of an approximate 16,000 species. 227 of these species are termed “hyperdominant”, because they represent about half of the total number of trees, while the rarest 11.000 species make up only 0.12% of the total.

Why only 227 species make up such a disproportional percentage of overall trees remains unknown.

“We knew that, normally, a few species dominate ecosystems, but if you have a system that has 16,000 tree species but just 227 make up half of the trees, that was pretty surprising even for us,” said lead author Dr Hans ter Steege from the Naturalis Biodiversity Center in the Netherlands.”

“In the paper, Dr. ter Steege and the team of more than 100 scientists wrote that there was no evidence that two key functional traits for trees – seed mass and wood density – played a part in determining what species dominated the landscape.” Read full article on BBC

Although the long and highly-involved history of human-forest habitation/impact/modification in Amazonia was not mentioned in the article(s), I am curious if the researchers have begun to look into the possible correlation between the 227 hyperdominant species and their ethnobotanical significance among past and present populations of Amazonian indigenous peoples. My guess is that the 227 hyperdominant species also have a wide range of human uses.

With recent findings confirming that sophisticated human societies inhabited the Bolivian Amazon 10,400 years ago, and that human habitation of the region likely dates back as far as 30,000 years, coupled with our firmly established understanding that Amazonian peoples have managed highly complex, large-scale domesticated landscapes (massive agro-silvo-pastoral systems), it seems inevitable that long-term human presence in the Amazon has played significant role in determining present day biodiversity and species distribution.

We’ll see what answers science comes up with.

Here are a few relevant articles on the subject of pre-Colombian Amazonian history, Amazonian agroforestry, and anthropogenic landscapes in the Amazon:

Clark Erickson: Culture amidst the Pristing: The Anthropogenic Forests of the Bolivian Amazon

NPR Article: Amazon was once home to advanced civilizations

Discovery News: Did humans arrive in the Americas 30,000 years ago?

New York Times: Once Hidden by Forest, Carvings in Land Attest to Amazon’s Lost World

Science Daily: Pre-Colombian societies in the Amazon may have been much larger and more advance then thought

Agroforestry and the Built Environment by: Spencer Woodard (Anthropogen):

New Yorker: Under the Jungle by David Grann

PDF: Amazonian Agroforestry and Homegardens