Sowing of ryegrass on a sorghum field (Nicola Dal Ferro)

Continuous soil cover on croplands (Italy)

Copertura continuativa del suolo

Description

Maintenance of continuous soil cover; alternating crops and cover crops as a practice to improve soil quality and reduce diffuse agricultural water pollution

Continuous soil cover on croplands in the Veneto region is characterised by growing seasonal cover crops alternated to the main crop. Continuous cover cropping has been promoted as an agri-environmental measure of the Rural Development Programme (RDP) by Veneto region to extend sustainable land management and reduce diffuse water pollution. Indeed cover crops incorporate available inorganic N that remains within the soil after harvest and reduce water erosion. The type of crop species depends on the crop succession.

Purpose of the Technology: Cover crops have been proposed to the farmers with the aim of reducing environmental impacts of traditional agricultural practices. Compared with systems that does not use cover crops, the continuous soil cover provides long-term agronomical and environmental benefits due to a reduction of negative impacts on agro-ecosystems.

Establishment / maintenance activities and inputs: The application of cover crops involves the alternation of autumn-winter cereals, rapeseed or other herbaceous crops with maize, soybean, sorghum etc. Cover crops that are sown after the main culture are neither fertilized nor treated with pesticides during growing, while at the end of the crop cycle they are buried as green manure in order to improve soil organic matter content, nutrient cycle and finally soil fertility.

Natural / human environment: Growing seasonal cover crops between annual crops have the potential to provide multiple benefits in a cropping system. Cover crops prevent water erosion and pollution as well as increase soil physical properties. Due to the effect of green manure and root growth, cover crops supply nutrients and increase soil organic matter content. They improve soil biodiversity and break pest cycles.

Location

Location: Low Venetian plain of Veneto region, Italy, Italy

No. of Technology sites analysed:

Geo-reference of selected sites
  • n.a.

Spread of the Technology: evenly spread over an area (approx. 10-100 km2)

In a permanently protected area?:

Date of implementation: less than 10 years ago (recently)

Type of introduction
Cover crop radish (Nicola Dal Ferro)

Classification of the Technology

Main purpose
  • improve production
  • reduce, prevent, restore land degradation
  • conserve ecosystem
  • protect a watershed/ downstream areas – in combination with other Technologies
  • preserve/ improve biodiversity
  • reduce risk of disasters
  • adapt to climate change/ extremes and its impacts
  • mitigate climate change and its impacts
  • create beneficial economic impact
  • create beneficial social impact
Land use

  • Cropland
    • Annual cropping: cereals - barley, cereals - rye, cereals - sorghum, legumes and pulses - beans, legumes and pulses - peas, Vetch (Fabacae)
    Number of growing seasons per year: 1

Water supply
  • rainfed
  • mixed rainfed-irrigated
  • full irrigation
Purpose related to land degradation
  • prevent land degradation
  • reduce land degradation
  • restore/ rehabilitate severely degraded land
  • adapt to land degradation
  • not applicable
Degradation addressed
  • soil erosion by water - Wt: loss of topsoil/ surface erosion
  • chemical soil deterioration - Cn: fertility decline and reduced organic matter content (not caused by erosion)
  • biological degradation - Bc: reduction of vegetation cover, Bp: increase of pests/ diseases, loss of predators
  • water degradation - Hp: decline of surface water quality
SLM group
  • improved ground/ vegetation cover
SLM measures
  • agronomic measures - A1: Vegetation/ soil cover

Technical drawing

Technical specifications
Continuous soil cover is here carried out with direct sowing of ryegrass on a sorghum field. Sorghum was in turn used as cover crop after harvesting of winter wheat.

Location: Low Venetian plain of Veneto region

Technical knowledge required for field staff / advisors: moderate

Technical knowledge required for land users: low

Main technical functions: control of raindrop splash, improvement of ground cover, increase of surface roughness, improvement of water quality, buffering / filtering water

Secondary technical functions: control of dispersed runoff: impede / retard, improvement of surface structure (crusting, sealing), increase in organic matter, increase in nutrient availability (supply, recycling,…), sediment retention / trapping, sediment harvesting

Cover cropping
Material/ species: e.g. barley and vetch, ryegrass, sorghum
Quantity/ density: 35 kg/ha

Green manure
Material/ species: e.g. sudan grass
Quantity/ density: 1.5-6 t/ha
Remarks: Strongly dependant on: 1) type of cover crop; 2) differentiation between summer and winter c.c.
Author: Nicola Dal Ferro

Establishment and maintenance: activities, inputs and costs

Calculation of inputs and costs
  • Costs are calculated:
  • Currency used for cost calculation: Euro €
  • Exchange rate (to USD): 1 USD = 0.8 Euro €
  • Average wage cost of hired labour per day: 21.00
Most important factors affecting the costs
Although machinery costs are the largest part of total ones, they are almost completely the same for systems adopting - or non adopting - the technology. As a result, additional seeds as cover crop and field labour for sowing are the main costs for implementation of the technology.
Establishment activities
n.a.
Maintenance activities
  1. Cover crops: chopping (Timing/ frequency: None)
  2. Main crop: seedbed preparation (Timing/ frequency: None)
  3. Main crop: harrowing (Timing/ frequency: None)
  4. Main crop: weed control (Timing/ frequency: None)
  5. Main crop: fertilisation (Timing/ frequency: None)
  6. Main crop: harvesting (Timing/ frequency: None)
  7. Cover crops: sowing (Timing/ frequency: None)
Maintenance inputs and costs
Specify input Unit Quantity Costs per Unit (Euro €) Total costs per input (Euro €) % of costs borne by land users
Equipment
Cover crop chopping ha 1.0 343.0 343.0
Main crop: seedbed preparation ha 1.0 191.0 191.0
Main crop: harrowing ha 1.0 63.0 63.0
Main crop: weed control ha 1.0 44.5 44.5
Main crop: harvesting ha 1.0 152.0 152.0
Cover crops: sowing ha 1.0 121.0 121.0
Plant material
Seeds main crop ha 1.0 190.5 190.5
Seeds cover crop ha 1.0 191.0 191.0
Fertilizers and biocides
Main crop: fertilisation (fertilizer) ha 1.0 254.0 254.0
Main crop: weed control (biocides) ha 1.0 125.0 125.0
Total costs for maintenance of the Technology 1'675.0
Total costs for maintenance of the Technology in USD 2'093.75

Natural environment

Average annual rainfall
  • < 250 mm
  • 251-500 mm
  • 501-750 mm
  • 751-1,000 mm
  • 1,001-1,500 mm
  • 1,501-2,000 mm
  • 2,001-3,000 mm
  • 3,001-4,000 mm
  • > 4,000 mm
Agro-climatic zone
  • humid
  • sub-humid
  • semi-arid
  • arid
Specifications on climate
Thermal climate class: temperate
Slope
  • flat (0-2%)
  • gentle (3-5%)
  • moderate (6-10%)
  • rolling (11-15%)
  • hilly (16-30%)
  • steep (31-60%)
  • very steep (>60%)
Landforms
  • plateau/plains
  • ridges
  • mountain slopes
  • hill slopes
  • footslopes
  • valley floors
Altitude
  • 0-100 m a.s.l.
  • 101-500 m a.s.l.
  • 501-1,000 m a.s.l.
  • 1,001-1,500 m a.s.l.
  • 1,501-2,000 m a.s.l.
  • 2,001-2,500 m a.s.l.
  • 2,501-3,000 m a.s.l.
  • 3,001-4,000 m a.s.l.
  • > 4,000 m a.s.l.
Technology is applied in
  • convex situations
  • concave situations
  • not relevant
Soil depth
  • very shallow (0-20 cm)
  • shallow (21-50 cm)
  • moderately deep (51-80 cm)
  • deep (81-120 cm)
  • very deep (> 120 cm)
Soil texture (topsoil)
  • coarse/ light (sandy)
  • medium (loamy, silty)
  • fine/ heavy (clay)
Soil texture (> 20 cm below surface)
  • coarse/ light (sandy)
  • medium (loamy, silty)
  • fine/ heavy (clay)
Topsoil organic matter content
  • high (>3%)
  • medium (1-3%)
  • low (<1%)
Groundwater table
  • on surface
  • < 5 m
  • 5-50 m
  • > 50 m
Availability of surface water
  • excess
  • good
  • medium
  • poor/ none
Water quality (untreated)
  • good drinking water
  • poor drinking water (treatment required)
  • for agricultural use only (irrigation)
  • unusable
Water quality refers to:
Is salinity a problem?
  • Yes
  • No

Occurrence of flooding
  • Yes
  • No
Species diversity
  • high
  • medium
  • low
Habitat diversity
  • high
  • medium
  • low

Characteristics of land users applying the Technology

Market orientation
  • subsistence (self-supply)
  • mixed (subsistence/ commercial)
  • commercial/ market
Off-farm income
  • less than 10% of all income
  • 10-50% of all income
  • > 50% of all income
Relative level of wealth
  • very poor
  • poor
  • average
  • rich
  • very rich
Level of mechanization
  • manual work
  • animal traction
  • mechanized/ motorized
Sedentary or nomadic
  • Sedentary
  • Semi-nomadic
  • Nomadic
Individuals or groups
  • individual/ household
  • groups/ community
  • cooperative
  • employee (company, government)
Gender
  • women
  • men
Age
  • children
  • youth
  • middle-aged
  • elderly
Area used per household
  • < 0.5 ha
  • 0.5-1 ha
  • 1-2 ha
  • 2-5 ha
  • 5-15 ha
  • 15-50 ha
  • 50-100 ha
  • 100-500 ha
  • 500-1,000 ha
  • 1,000-10,000 ha
  • > 10,000 ha
Scale
  • small-scale
  • medium-scale
  • large-scale
Land ownership
  • state
  • company
  • communal/ village
  • group
  • individual, not titled
  • individual, titled
Land use rights
  • open access (unorganized)
  • communal (organized)
  • leased
  • individual
Water use rights
  • open access (unorganized)
  • communal (organized)
  • leased
  • individual
Access to services and infrastructure
health

poor
good
education

poor
good
technical assistance

poor
good
employment (e.g. off-farm)

poor
good
markets

poor
good
energy

poor
good
roads and transport

poor
good
drinking water and sanitation

poor
good
financial services

poor
good

Impacts

Socio-economic impacts
Crop production
decreased
increased

drinking water availability
decreased
increased

irrigation water availability
decreased
increased

irrigation water quality
decreased
increased

workload
increased
decreased

Socio-cultural impacts
national institutions
weakened
strengthened

SLM/ land degradation knowledge
reduced
improved

Improved livelihoods and human well-being
decreased
increased

Ecological impacts
water quality
decreased
increased

surface runoff
increased
decreased

soil cover
reduced
improved

soil loss
increased
decreased

nutrient cycling/ recharge
decreased
increased

soil organic matter/ below ground C
decreased
increased

biomass/ above ground C
decreased
increased

pest/ disease control
decreased
increased

Off-site impacts
downstream flooding (undesired)
increased
reduced

groundwater/ river pollution
increased
reduced

buffering/ filtering capacity (by soil, vegetation, wetlands)
reduced
improved

Cost-benefit analysis

Benefits compared with establishment costs
Benefits compared with maintenance costs
Short-term returns
very negative
very positive

Long-term returns
very negative
very positive

Establishment costs N/A

Climate change

Gradual climate change
annual temperature increase

not well at all
very well
Answer: not known

Adoption and adaptation

Percentage of land users in the area who have adopted the Technology
  • single cases/ experimental
  • 1-10%
  • 11-50%
  • > 50%
Of all those who have adopted the Technology, how many have done so without receiving material incentives?
  • 0-10%
  • 11-50%
  • 51-90%
  • 91-100%
Has the Technology been modified recently to adapt to changing conditions?
  • Yes
  • No
To which changing conditions?
  • climatic change/ extremes
  • changing markets
  • labour availability (e.g. due to migration)

Conclusions and lessons learnt

Strengths: land user's view
Strengths: compiler’s or other key resource person’s view
  • Prevents erosion

    How can they be sustained / enhanced? Maintenance of cover crop
  • Improves soil fertilty, biodiversity, structure, organic matter content

    How can they be sustained / enhanced? Usage of organic fertilizations on the main crop
  • Allows natural control of weeds

    How can they be sustained / enhanced? Higher seeding rate
  • Improves knowledge on soil cover benefits and agroecology

    How can they be sustained / enhanced? Improve farmers' education
Weaknesses/ disadvantages/ risks: land user's viewhow to overcome
  • Increase costs of input and management Increase awareness on long-term soil benefits and keep subsidies
  • In summer seasons increases the competition for water resources improve planning and knowledge of suitable species
Weaknesses/ disadvantages/ risks: compiler’s or other key resource person’s viewhow to overcome

References

Compiler
  • Nicola Dal Ferro
Editors
Reviewer
  • Fabian Ottiger
  • Alexandra Gavilano
Date of documentation: Oct. 22, 2014
Last update: Sept. 4, 2019
Resource persons
Full description in the WOCAT database
Linked SLM data
Documentation was faciliated by
Institution Project
Key references
  • Programma di sviluppo rurale per il veneto 2007-2013, Regione Veneto, 2007. Dipartimento Agricoltura e Sviluppo Rurale.:
This work is licensed under Creative Commons Attribution-NonCommercial-ShareaAlike 4.0 International