CONSOWA 2017

''Sustainable Life on Earth through Soil and Water Conservation''

12-16 June, Lleida (Spain)

Day 1 (Monday 12th of June)

The first day of the first Word Conference on Soil and Water Conservation under Global Change started with

the opening session by Professor Ildefons Pla Sentís and Professor Enric Mir, representing the Diputació de

Lleida and Professor Narciso Pastor, representing the Universitat de Lleida. Professor Pla emphasised the

challenges of practicing soil and water conservation under global changes such as climate change, change in

land use, population growth, soil erosion, sediment displacement and floods. He then pointed out that

CONSOWA was the first congress that joined all the main organisations in soil and water conservation in the

world. The organisation involved were: WASWAC (World Association of Soil and Water conservation), IUSS

(International Union of Soil Science), ISCO (International Soil Conservation Organization, Soil and Water

Conservation Society, ESSC (European Society for Soil Conservation, IECA (International Erosion Control

Association) (proof according to him that some Americans still believe in science), WASER (World Association

for Sedimentation and Erosion research), and EGU (European Geosciences Union). The conference occurred on

the 700th anniversary of the foundation of the University of Lleida, one of the oldest in Europe, and the 300

participants arrived from over 40 countries, some of them with difficulties.

The opening keynote presentation was from Professor Rattan Lal from Ohio State University, president of the

International Union of Soil Science. Professor Lal presentation addressed the main global challenges: global

population growth, soil erosion, salinization, algal blooms, loss of agricultural land, species extinction,

deforestation, ground water depletion, GHGs emissions, and loss of carbon. He highlighted the necessity of

ecological restoration of world soils. He then focused on the ecological effects associated with soil erosion, and

the problem of carbon depletion. He stated the necessity of having much-based farming systems, which use,

for example, gravel mulches, water mulches, no tillage, crop residue, and cover cropping. Professor Lal insisted

on the importance of sustainable intensification for the future of humanity; it is necessary to use less land,

water, energy to produce food, and produce more to end hunger and poverty. His presentation ended with a

panorama of the main technological innovations from the year 1750 to the present day and beyond. From

today to 2025 new challenges and research areas are: sustainable intensification, rhizosphere processes,

disease-suppressive soils, soil-less agriculture, the nexus approach, phytobiome management, precision

farming, and soil restoration, and beyond the year 2025: recarbonisation of the biosphere, nutrition sensitive

agriculture, restorative agriculture, urban/sky farming, and space farming.

Professor Winfried Blum from the University of Natural Resources and Life Sciences of Vienna talked about the

threats to soil and water conservation and the challenge posed by the complexity of the conservation task. In

summary, soil and water degradation has cultural, social and economic driving forces, which change in space

and time. For example family structure, income and health are important at farm scale; while, energy prices

and the World Trade Organization are important at world scale. Soil and water degradation has also ecological

and technical driving forces, like soil distribution patterns and macroclimate at regional scale and climate

change at world scale. He concluded his presentation talking about the necessity of scientists to support

politics into decision making by creating future scenarios based on multidisciplinary approaches.

Dr José Rubio presented new perspectives for soil and water conservation. He gave an overview of the

historical evolution of soil conservation, from intuitive practices to the modern use of bioengineering and the

recognition of ecosystem services. He concluded talking about the necessity of implementing soil and water

conservation practices more effectively and improving social awareness.

Professor Samir El-Swaify from the University of Hawaii talked about the diagnostic criteria for soil degradation

and the necessity of distinguishing criteria for the tropical soils. Briefly, most soil degradation diagnostic criteria

were developed in temperate regions, and therefore are not adapt to tropical regions. Typical tropical soil are

highly weathered oxisols, with low nutrients and stable structure. They have a content of iron oxides around

40%, which makes them active agents. Another type of soil is volcanic ash soils, which are mostly permanently

wet and therefore cannot be dried according to the standard procedures.

Professor Carmelo Dazzi from Universitá degli studi di Palermo and president of ESSC spoke about the

environmental and economic considerations regarding anthropogenic soils. He emphasised the importance of

an economical evaluation of the ecosystem services provided by soils and presented a case study of

pedotechiques applications in Sicily. Concisely, Sicilian growers are converting their soils from vertisols to

anthrosols by adding tons of calcium carbonate to grow table grape and gaining an economical return in 5

years, loosing, however, many ecosystem services.

Figure 1: Professor Lal talking about mulch-based farming systems.

After the keynote presentations, there was a poster session, followed by two contemporary presentation

sessions. I followed the session on climate change, soil organic carbon and soil degradation processes. Among

the many presentations, I found particularly interesting the presentation by Dr Pholosho Kgopa on soil active

and organic carbon stocks as affected by cultivation and irrigation with treated wastewater and the

presentation by Sharma Chiranjivi on the impact of climate change on water availability in the Dr Mugu Karnali

river basin of Nepal Himalayas.

Day 2 (Tuesday 13th of June)

The second day of the conference started with a talk by Dr Ru Li from the Institute of Soil and Water

Conservation in Yangling. Briefly, soil erosion and flooding have been increasing in China in the past century.

Most of the crops are cultivated on slope lands; to mitigate soil erosion many terraces have been built. In

addition to that, Dr. Li presented the Grain for Green project, which aims to restore the Loess Plateau of China

by planting trees and grass. From the start of the project at the end of the 90s, forest and grass have increased

in China by 4.5%.

Professor Zhaoyin Wang from the Tsinghua University presented the two-thousand years long debate about

managing the sediments of the Yellow River. In summary, the sediments come from the Loess Plateau, where

the erosion rate is estimated to be 10,000 t/yr. km2. During history, two different approaches to manage the

sediments have been adopted. The first approach is to narrow the river channel, increasing the flow velocity

and bringing the sediments to the sea, the second is to increase the size of the river channel and enhance

sediment deposition in secondary channels and flood plains. This second approach has been the most

successful to control floods. However, new challenges are costal soil erosion, which in the past was

compensated by the sediments deposition, and the exhausted water resources. He also mentioned the

interesting practice to use dams to create artificial floods to scour the riverbed.

Professor Roy Sidle from the University of the Sunshine Coast talked about the dynamic environmental controls

on rainfall-trigged landslides. Concisely, rapid landslides, shallow or deep, are initiated by an increase in pore

water pressure. They can create a lot of damage, like what happened in the Philippines in 2006, where 1100

people died because a 15 million m3 landslide. Trees reduce landslide risk, due to evapotranspiration and root

reinforcement; however, they are not very important in shallow landslide in winter. Therefore, It is important

to research the other factors a part of rainfall that affect the initiation of these slope failures.

Dr Wang Fei from the institute of China gave the last keynote presentation of the day on the impact of re-

vegetation on the Chinese loess Plateau on surface soil moisture and the new challenges of soil and water

conservation. To summarise, the Loess Plateau is the most highly erodible soil on earth. Cropland on steep

slopes, over-grazing and land degradation are problems associated with the area. The artificial re-forestation

on the Plateau has remarkable ecological benefits; however it has reduced the soil moisture, leading to an over

consumption, which in the future will lead to drought. He concluded the presentation suggesting focusing on

selecting the appropriate vegetation and plants density.

Before lunch, there was a discussion session. Professor Dazzi, Professor El-Swaify, Professor Rubio, Dr Benson

and Professor Pla formed the panel. The discussion touched different subjects among which the requirement

of global collaboration into the application of soil and water conservation practices, the need of applying

scientific knowledge, and of improving science communication and public engagement. Dr Helena Cotler, from

Mexico made an interesting intervention about the need of taking more into consideration the social,

economic and gender factors related to soil and water conservation. She said that, for example, most farmers

in South America are women, and therefore a gender approach is necessary; she also added that female

representation in the conference should have been greater. The discussion concluded with Dr Benson

reflection on Dr Helena Cotler’s intervention, he talked about the necessity of adopting socio-ecological

approaches to solve environmental problems and argued about the necessity of new multidisciplinary

professional figures and new multidisciplinary research areas e.g. hydro-sociology, ecological-economy etc.

In the afternoon there was a poster session followed by two parallel presentation section. I participated to the

session on climate change, soil organic carbon and soil degradation processes and soil and water conservation

practices, during which I presented my research. All presentations were stimulating, but I am going to mention

only a few. Dr Greet Ruysschaert presented her research on strip-tillage for erosion reduction in maize. Dr

Dieter Nill presented the activities of the German Development Cooperation, he discuss the difficulties of

scaling up soil and water conservation measures to landscape level in Africa. Dr Helena Cotler talked about the

adoption of soil conservation practices in Mexican agroecosystems, and the necessity of understanding the

family, institutional and economic factors which affect the adoption soil conservation practices. Dr peter

Strauss talked about the temporal and spatial heterogeneity of soil cover management in Austrian vineyards;

they also developed a program to estimate canopy cover and ground cover, which can be downloaded for free

from: https://soilcover.josephinum.at , there is also an app available.

In the evening, there was the ceremony of Doctor Honoris Causa attributed to Professor Rattan Lal. Professor

Pla enumerate Professor Lal achievements and contributions to science during the past 50 years, especially in

the field of climate change and carbon sequestration.

Figure 2: Discussion panel. Figure 3: Professor Lal during the ceremony.

Day 3 (Wednesday 14th of June)

During the third day of the conference, I participated to a field trip looking at the land use change and soil

erosion processes in the pre-Pyrenean Valleys. We visited the Tremp basin, located in the Geopark project

Conca de Tremp-Montsec. The changes in land use in the area caused severe soil erosion and mass

movements. The first stop offered us an overview of the Tremp basin, where Dr Goncal Rivas and Dr Rosa Poch

explained the geology of the area and the land use.

Figure 4: View of the Tremp basin

Figure 5: Geologists explaining the complex geology of the area.

During the second stop, we visited the Rubió Badlands, downhill from the old town of Toló, which in the past

was and important settlement. The area was cultivated in terraces but it was abandoned when the border with

the Islamic Empire moved south. The land degraded and sever soil erosion occurs, especially in spring, due to

the winter weathering of the marls.

Figure 6: Badlands with sever soil erosion. Some terraces are still visible.

During the third and fourth stop, we visited the surrounding countryside and Dr Poch explained the results of

land use change. A problem of the area is the increased soil erosion due increased average slope length caused

by plot merging. Another environmental issue is caused by the many animal farms present in the area, which

provide many organic fertilizers that applied to the fields without control, causing over-fertilisation; however,

the aquifer is not affected because of the natural geology of the area. There are soil erosion control measures

in place like terraces and dry stone walls.

Stop 5: Isona, where we exposed a soil profile, see picture 8. The soils in the area have high calcium carbonate

accumulation and limited organic matter.

Figure 7: Calcareous soils

Figure 8: Soil profile

During the next stop we visited the Institut of Cartografic I Geologic de Catalunya where they conserve many

soil profiles, see the following pictures.

Figure 9: Some examples of soil profiles from the ICG. Interesting is the profile on the left with two organic layers separated by two mineral horizons.

The seventh stop of the day was Castell De Mur and Santa Maria De Mur. Castell De Mur is a Roman castle well

preserved because of the type of stone used to build it.

Figure 10: Tower of the castell.

Figure 11: Roman Toilet on the left, discharging on the external walls on the right. On the outside of the toilet used by noble people there are more plants than outside the toilet used by the servants because nobles ate meat.

Figure 12: Landscape from the castell.

Figure 13: Dr Rosa Poch explaining the landscape visible from the castell. On the distance Terradets reservoir, which now has no more flood control capacity due to the sediments accumulated from agricultural fields.

Day 4 (Thursday 15th of June)

First presenter was Professor Walter Pengue, from National University of General Samiento, Argentina, who

talked about the mining of soils in the Argentinian Pampas and the hidden costs of technological intensification

in industrial agricultural models. He explained the key concepts of virtual soils and water, nutrients footprint,

industrial agriculture and pampeanization. Summing, virtual soils represent the land dedicated to food

production and virtual water is the water involved in the complete process of food production, together with

nutrients footprint they are the hidden costs of industrial agriculture. Pampeanization is the process of land

conversion from forest to industrial agriculture. Industrially grown GMO soybeans are the major crop cultivated

in Argentina. As consequence, the landscape has been transformed, there is an increase of weed resistance to

herbicides, soil structure degraded, and desertification is increasing.

Professor Gustavo Marten of the Federal University of Rio Grande do Sul, Brazil, talked about the soybean

expansion in Brazil. In summary, soybeans are the crops mostly cultivated in Brazil. Due to the poor nutrients

status of the soils (oxisols) a lot of fertilizes are used. Consequences of the expansion of soybeans cultivation

are soil erosion, decrease of water infiltration, and land use change (deforestation). Massive terraces, cover

cropping and no till were soil conservation practices in place in the 80s to mitigate the erosion problems; these

practices should be more widely adopted. He concluded his presentation talking about the necessity of market

initiatives to drive the adoption of sustainable practices.

Professor Miodrag Zlatic from Belgrade University, Serbia, talked about the socio-economic issues of torrential

flooding prevention. Briefly, in May 2014, there was a great flood in Serbia and many houses were destroyed

because built too close to the river. It is necessary to improve the system of prevention and prediction of

torrential floods, and financing torrent control works.

Professor Fernando Delgado, from CIDIAT University of Los Andes, Venezuela, talked about soil-water-climate

management and conservation systems in ancient cultures of tropical Latin America. The presentation was an

overview of the pre-Hispanic agriculture in South America. Summarising, Maya culture practiced slash and

burning cultivation, with a long period of recovery. They integrated their agriculture into the forest system,

using a system called Milpa, where mixed of crops (maize, beans and pumpkin) are cultivated in patches in the

Maya forest. In the high plains ancient Latin cultures had to deal with seasonal water excess and cold climate,

the mitigate the problem using raised fields.

Figure 14: Raised field presented by Professor Delgado.

The Pucara culture to reduce the water shortage in cold and dry regions creating temporary lagoons and ponds

and growing crops around these ponds, seeding concentric as the water reduced. Professor Delgado also talked

about the complex terraces systems of the Inca Empire. These examples can be promising models to improve

modern agriculture. He concluded his speech taking about the devastating situation in Venezuela, where civil

war is imminent and he ask us to pray for his country.

The morning concluded with a panel discussion on the International Decade of Soils. Members of the panel

were Professor Winfried Blum, Dr Mark Nearing, Professor Li Rui, Dr Goncalo Farias and Professor Pla. The

discussion focused on the International Decade of Soils, launched by IUSS in Vienna in December 2015. Dr

Goncalo Farias stressed the importance of transforming scientific declarations into a continuous set of practical

actions by preparing guiding documents for a worldwide good governance of soils. Dr Nearing talked about the

importance of changing the word diet to a more plant based diet to reduce the pressure on food production.

Figure 15: Discussion panel.

In the afternoon there was a poster session followed by two parallel presentation sessions. I participated to the

session on soil and water conservation practices, salinization and contamination of soils and waters, and

hydrological processes on soil and water conservation. During this section among the many presentations,

Professor Pla presented the traditional rainwater harvesting systems for agricultural use in Lanzarote and

Fuerteventura Islands. Among them the 'Arenados', circular cavities protected by a stone wall which are used

for wine production.

Figure 16: Professor Pla talking about Arenados.

Day 5 (Friday 16th of June)

The last day of the conference started with the presentation from Dr Fenli Zheng on soil erosion, soil quality

and crop yield in Chinese Mollisol region. Briefly, the mollisols of China have lost the majority of the organic

horizon due to soil erosion. Her project looked at the effect of soil erosion and soil quality on yield in the

Binzhou river basin. Soil erosion was monitored with 137Cs and erosion plots, soil quality index included 15

indicators. Soil erosion rate and SOM had a significantly negative correlation, corn yield in the eroded areas

reduced of 12%.

Dr Miquel Aran talked about the role of organic and inorganic fertilisers on soil degradation in the intensive

arable land of West Catalonia, Spain. The problem in the area is the over-fertilisation with organic fertilisers,

more regulation is necessary.

Professor Pla talked about the new advances in the evaluation of salt-affected soils under dryland and irrigated

conditions. He explained the difference between saline soil (they cause water deficit for plants) and sodic soils

(negative effect of sodium on soil physical properties) and presented some projects where he was involved like

in Guantanamo, Cuba and Barahona, Republia Domenicana.

Professor Artemi Cerdá talked about the effect of fire on soils and erosion processes. In brief, the problem

associated with forest fires depend on the temperature of the fire and on the extension of the fire. High

temperature can cause water repellence, however forest ashes increase water infiltration. Erosion processes

can be devastating in an area affected by fire, it is therefore important to try to cover the soil quickly; he gave

the example of using straw mulch involving the local population in the application process. He concluded the

presentation talking about the requirement to have small controlled fires to prevent the devastation of

enormous fires.

The afternoon section was about the reclamation of degraded soils and waters and salinization and

contamination of soils and waters. Among the many presentations, peculiar was the presentation of Patrick

Pierron on the PLAN.T>E project, which is aiming to plant trees in the sub-Saharan regions using explosives.

The conference concluded with Professor Pla’s closing speech.