Responsible partner:	»Soil and Fertilizer Institute of the Sichuan Academy of Agricultural Sciences (SFI)
Authors:	Hongzhu Fan
iSQAPERiS editor:	Jane Brandt

 

Contents table

1. Infographics and videos

2. Study site description

3. Participation of stakeholders in the iSQAPER research programme

4. Research tasks

5. Long-term impact of iSQAPER's research programme in the study site

1. Infographics and videos

遂寧市研究現場小組製作了一個短片，以演示視覺土壤評估的使用。 

A short video was made by the Suining study site team to demonstrate the use of visual soil assessments.

	視頻	Video
	»在遂寧研究區評估土壤質量 在中國遂寧的iSQAPER研究地點進行了小麥和水稻轮作長期田間定位試驗。 iSQAPER科學家與農民合作，在不同的農業實踐下監測了許多不同的土壤質量。 （用英語講）	»Assessing soil quality in the Suining study site Long term field trials of rice-wheat rotation have taken place in the iSQAPER study site in Suining, China. Working with the farmers, iSQAPER scientists have monitored many different of soil quality under different agricultural practices. (in English)

 2. Study site description

Location

Calcareous Purplish Soil field station was established in 1982, in Suining city of Sichuan province, which is in the middle of hilly Sichuan basin. This region belongs to a sub-tropical humid monsoon climate, with a mean annual temperature of 18.5 ˚C and rainfall of 927 mm. Agricultural lands comprise 0.15 million hectares, with Calcareous Purplish Soil land accounting for 62%. The main agricultural crops are grain, cotton, oil, fruit, and mulberry. Rice-wheat and rice-rape rotation are the main farming systems in this area. Irrigation water is derived from both the Peijiang River and from rainfall sources. Population density is 813 people per km².

Suining, China
Farming landscape
Farming landscape

Main farming systems and typical agricultural management activities in the study area

The main farming systems are rice-wheat rotation and rice in this study area. Overuse and under-application of fertilizer occurred within this cropping system. Farmers prefer to use more N fertilizer which has led to an in-balance in N, P and K and the N application timing did not match the crop nutrient demand. Nutrients from the natural environment and the characteristics of nutrient dynamic during the rice-wheat rotation period were not considered when farmers determined the fertilizer application rate. The strategy included nutrient management from the whole rotation system perspective, the integrated use of nutrients from various sources (chemical fertilizers, organic fertilizers and nutrients from the environment), using different management technologies according to the characteristics of different nutrient resources, and integrating nutrient management with other cropping system technologies, such as water saving and high yield cultivation.

Main agricultural crops in Sichuan

 
 
Fertillization treatments

Characteristic soils and soil quality monitoring practice

The soil is a calcareous purple paddy soil, with the main mineral consisting of hydromica, kaolinite and quartz. When the field experiment station was established in 1982, the top 20 cm of soil contained 15.9 g kg^-1 soil organic matter (SOC), 1.09 g kg-1 total N (TN), 3.9 mg kg^-1 Olsen-P (OP) and 130 mg kg^-1 exchangeable K (EK) with a pH value (soil-to-water ratio 1:1) of 8.6 at the start of the experiment. Soil quality monitoring practices include: i) collection crop yield data from 1982 to 2013, ii) monitoring soil total N, P, K, SOC, Olsen-P, EK and pH in 1986, 1990,1994, 1998, 2006 and 2012.

Previous research and innovation actions on soil improvement and monitoring

Ongoing research and innovation actions on soil focuses on: i) crop yield evolution under long-term fertilization, ii) effect of long-term located fertilization on soil potassium balance and form transformation in purple soil under paddy rice and wheat, and iii) soil microbe, organic carbon fractions and their recycles.

3. Participation of stakeholders in the iSQAPER research programme

The local stakeholders listed in Table 1 were involved throughout the duration of iSQAPER in a number of research tasks including: providing experimental sites for the soil quality assessment and agricultural management practice evaluation; testing and evaluating SQAPP; attending demonstration workshops; and providing venues for and hosting the field visits for the iSQAPER plenary meeting.

Table 1: Local stakeholders involved in the iSQAPER research programme

Stakeholder type	Locations	Institution	Number and gender M/F	Role
Farmers, land managers	Yuanbao Village,Yongxing Town,Chuanshan District,Suining City	Farm	3M, 4F	Landowner and land manager (majority), land worker
Advisors	Yongxing Town,Chuanshan District,Suining City	Farm cooperation	5M, 2F	Provider of information /advice to land managers creating market opportunities for product, equipment and tool provision, product retail, and agriculture material of pesticide, seed and fertilizer
Policy-makers	Chuanshan District, Suining City	Agricultural Bureau of Suining	2M, 1F	Regulation and enforcement of national crop farming, agriculture economic development plan or policy
Researchers	No. 4 Shizishan Road, Jinjiang District Chengdou, Sichuan China	Soil and Fertilizer Research Institute,Sichuan Academy of Agricultural Sciences	3M, 2F	Researcher, land manager

4. Research tasks

Soil quality assessment and agricultural management practice evaluation

Based on WOCAT database (www.wocat.net), iSQAPER selected 18 promising agricultural management practices (AMPs) with potential to improve soil quality (»Agricultural management practices in the iSQAPER study sites). Seven examples of a number of these AMPs were identified in the Suining study site that conformed to the following criteria:

1. the promising management practice has been implemented for at least 3 years;
2. at least 2 different soil types are represented; and
3. at least in 2 different first level Farming Systems (arable, permanent, grazing) are represented.

For each AMP plot, nearby control plots were also identified where the practice has not changed.

Table 2: AMPs identified in the Suining study site. Climatic region: Central subtropical

Plot number	Farming system	Farming system detail	Soil type	AMP general description	AMP number*
12.1	Arable	Non irrigated arable land - Maize	Anthrosols	Residue maintenance / Mulching	8
12.2	Arable	Non irrigated arable land - Maize	Anthrosols	Green manure / Integrated soil fertility management	6
12.3	Arable	Non irrigated arable land - Maize	Anthrosols	Manuring & composting	7
12.4	Arable	Permanently irrigated land - Cereals; Oil crops	Anthrosols	Manuring & composting	7
12.5	Arable	Permanently irrigated land - Cereals; Oil crops	Anthrosols	Residue maintenance / Mulching	8
12.6	Arable	Permanently irrigated land - Oil crops	Anthrosols	Min-till	2
12.7	Arable	Permanently irrigated land - Cereals; Oil crops	Anthrosols	Min-till; Residue maintenance / Mulching	2-8

*Note: see »Assessing effect of management practices on soil quality - experimental framework for the full list and descriptions of the 18 promising agricultural management practices.

A first field campaign was conducted in 2016 to evaluate the soil quality in each of the paired AMP-control plots, using visual soil assessment methods (»Visual soil and plant quality assesment). The results from this and all the other study sites were combined to determine which AMPs can be shown to have a proven positive effect on soil quality, see »Assessing effect of management practices on soil quality - experimental results.

Those practices that are innovative for China were also described and added to the WOCAT database

• »Straw residues left on field after harvest and no tillage [China]

The soil assessment campaign was repeated in 2018 on the paired plots highlighted in green in Table 2 (12.1: Residue maintenance / Mulching) with laboratory-based measurements added to the visual soil assessments. The aim was to investigate

• how measurements of soil quality parameters obtained from the visual assessments compared to those obtained from laboratory measurements;
• if different AMPs affected different soil quality parameters in different ways;
• and what impact the AMPs had on the principal soil threats.

For details of the assessment analysis methods and the results from this and all study sites see »Impact of promising agricultural management practices.

As a result of this extended analysis, the example of residue maintenance/ mulching that was exemplified in Plot 12.1 (which combined straw mulching and no tillage) was selected to demonstrate the positive impact management practice can have on soil quality (see »Demonstration events in the study sites).

Soil properties
Soil threats

This practice of diverse crop rotation maize-wheat aims to increase organic matter content and reduce soil erosion compared to the control rotation using rice-rape. No differences in the VSA soil structure quality scores were found between the AMPand control and, with the exception of moderate structure and stability and poor earthworm counts, all other indicators were good. Measured properties show minimal differences that cannot be reliably attributed to the use of the AMP.

SQAPP development, testing and evaluation

At the demonstration workshop on 21 August 2019, participants fwere asked a series of questions relating to their expectations of SQAPP and the relevance of the soil parameters included in SQAPP, the assessment of soil threats and the suitability of the app's recommendations to their local context. The feedback and comments were combined with those from the other study sites and used in the further development of SQAPP. For details of the responses from all study sites see »Stakeholder feedback and SQAPP development.

Stakeholders completing the SQAPP evaluation questionnaire
 

Demonstration workshops

On 21 August 2019 a demonstration event was organised in the Suining study site to present the major findings of iSQAPER to stakeholders and to demonstrate straw mulching and no tillage as a management practice of proven benefit to soil quality. The event was attended by 24 participants.

Participants at the demonstration event

The results from this demonstration event and those held in the other study sites are summarised in »Demonstration events in the study sites.

A leaflet describing the AMP combining straw mulching and no tillage was prepared to accompany the demonstrations.

English version
 
Chinese version
 

 »Straw mulching and no tillage, China

Co-development of scenarios of future farm and soil management practices

Members of the Suining study site team attended and contributed to the workshop in Madrid on developing scenarios of future farming. The results are presented in »Soil management scenarios. 

4. Long-term impact of iSQAPER's research programme in the study site

Taking account discussions with the Suining study site as indicated in Table 3.

Table 3: Activities in which iSQAPER's research programme could potentially have a lasting impact in the Suining study site

Activity	Impact level: 0 - no impact, 1 - barely noticeable to 5 - important visible impact
	0	1	2	3	4	5
Research results influencing farming practice				x
Uptake of recommended AMPs					x
Regular use of SQAPP			x
Development of new or enhancement of existing stakeholder networks		x
The involvement of new stakeholder types in existing networks		x