FBO technology effects on soil macroinvertebrate ...

2 downloads 0 Views 167KB Size Report
Yongtao Li, Luo Zhong Hai, Zhang Chi, Pradeep Panigrahi, Bikram Senapati, ... The FBO technology was invented in the early 90's by Professor Bikram ...
1

Institut de Recherche sur le Développement

Adaptation of the FBO (Fertilisation Bio-organique) technology in Southern China (Yingde, Guangzhou province)

Patrick Lavelle, Bao Gui Zhang, Jun Dai, Yongtao Li, Luo Zhong Hai, Zhang Chi, Pradeep Panigrahi, Bikram Senapati, Elena Velasquez, Nuria Ruiz-Camacho, Liu Li

Genesis of the project The FBO technology was invented in the early 90’s by Professor Bikram Senapati and his research team of Sambalpur University (Orissa, India) as part of an European Community project (MACROFAUNA, TS3*0292 EDB. (1992-1995) lead by Professor Patrick Lavelle (University of Paris VI /IRD). The objective of the project was to assess the value of earthworms as a resource in tropical agricultural systems. The technique soon gave greatly positive results and a patent was deposited in Sri Lanka in 1996 (ref. n° 11034, 4/9/96) and China (2005). A new pilote experiment has been run in Tamil Nadu India, confirming results obtained in the early experiments (Panigrahi, 2003). In 2003, a PRA project was submitted by Prof. BaoGui Zhang (Beijing Agricultural University) and Prof. Patrick Lavelle to the Franco Chinese scientific cooperation PRA programme to experiment the technology in China. South China Agricultural University (Prof. Dai Jun) and Tea Institute à Yingde were associated to the project and additional financial support was provided by IRD/DEV and French Embassy. Principles of the FBO technology Conventional agricultural practices based on high levels of chemical inputs (fertilisers and pesticides) and soil tillage are nowhere sustainable. Soil degradation occurs after a few decades or even years of use due to decreases in organic matter, dispersion of the soil structure and increase in soil toxicity due to pesticide residues. In such soils, invertebrate communities are drastically reduced and part of the degradation is directly a result of their disappearance. According to FAO, 20% of cultivated soils worldwide already suffer severe degradation and a much larger proportion is already in the process.

2

FBO restores soil function by inoculating earthworms, the most efficient invertebrates as regards maintenance of soil fertility in soils where suitable conditions for their activities hace been restored. •

Organic matters of contrasted qualities are brought to the soil according to a specific spatial design.



Soil is then inoculated with earthworm populations present in the region, specifically adapted to local soil conditions

It normally consists in a single strong intervention that restores the natural capital of soil fertility. After this phase, it is recommended to use organic rather than chemical fertilization and biopesticides (or no pesticides at all) rather than chemical fertilisers to allow restored soil fertility to become sustainable. Earthworms play a key role in soil restoration through 5 processes: 1. Improvement of soil physical properties increasing porosity, soil aggregation and resistance to erosion; 2. Enhanced release of nutrients from decomposing organic matter in synchrony with plant demand; 3. Protection from pests and diseases, directly or indirectly (through enhanced plant vigor); 4. Selective stimulation of microbial activities; 5. Hormone like effect stimulating plant growth and health.

Application at Yingde (Guangdong Province) An experiment was set at Yingde using a fully randomised protocole, with four different treatments replicated in three blocks: T1: 100% FBO technology : after application of FBO technology, fertilisation is fully organic and in case of severe insect attacks, only biopesticides are used. T2: 50% FBO; biopesticides: application of FBO and fertilisation half chemical, half organic. Use of biopesticides if necessary. T3: 50% FBO; chemical pesticides. T4: Conventional. This control soil receives the same amount of nutrient application

3

than the other three treatments, as chemical inputs. Chemical pesticides are used to control pests. Parameters measured during the experiment The experiment started in October 2004 with the installation of the experiment. At the same time, a full set of indicators of soil quality were measured in 20 different sites representing the diversity of landuse types in the region. This would allow to compare the state of soil quality in our experimental plots with neighbouring situations. Sampling was done at the following dates: October 2004; March 2005; October 2005; September 2006. Parameters measured were: •

Physical: resistance to penetration, bulk density



Soil morphology: assessment of soil aggregation and organic residues in soil



Macrofauna: sampling of macro invertebrate communities and identification to large groups (15 orders)



Chemical: assessment of all parameters of chemical fertility

Tea leaf production was measured every three months (march, june, October) and the biochemical and overall quality of tea were measured with a set of specific parameters. Results are presented in the next summaries and articles. Results After two years of experiment the following results were obtained: 1. Soil physical structure was significantly improved, first in the microsites where the FBO technology had been applied, and then outside these specific microsites. Parameters of chemical fertility did not change. 2. Biodiversity in soil increased and fauna shifted from communities dominated by ants and phytophagous invertebrates to communities dominated by decomposers, predators and earthworms. 3. Production was sustained at the same level in FBO and conventional treatments 4. One year after the onset of the experiment, the quality of tea assessed by the compound quality score index significantly increased in FBO treatments as compared with conventional; 100% organic FBO always had the highest scores. Increase in June 06, after 18 months was 13% as compared to control value.

4

5. A preliminary economic evaluation of the system indicates a 72% increase of profitability after 3 years, in spite of a significant initial investment. This is mainly due to the shift to organic production and increase in quality of the product. Conclusion At Yingde, restoration of soil quality by the FBO technology allowed a rapid shift from conventional to organic tea production. Tea production is sustained at the same level although with a better quality product. Better quality of soils allows tea plantations to provide increased levels of ecosystem services like e.g., water storage, resistance to erosion and flood control, pest control by more biodiverse soil communities, carbon storage with positive effects on climate (decreased release of greenhouse gases) and reduced or absent use of pesticides with negative effects on environment and human health.

5

Effects of the FBO technology on soil chemical and physical characteristics and microbial biomass Report: Zhang Chi

Abstract

The Bio-organic Fertilization technology (FBO) was applied in tea plantation in

Yingde, Guangdong province in November 2004 planted 5 years ago to Huang Jingui tea. Three experimental field plots were laid out in a completely randomized block design with 4 treatments.

The

experiment

was

designed

as

follows:

(T1)

100%FBO;

(T2)

50%FBO+bio.pesticide; (T3) 50%FBO+chem.pesticide; (T4) 100% chemical fertilizer. There were 3 replicates in each treatment. The main results as follows: (1) Soil decompaction: soil bulk density and rigidity decreased in the FBO treatments after 12 months, there were significant difference for the soil bulk density between FBO treatment and the chemical fertilizer treatment (PT4. The second axis (F2) is showing a difference between soil macro-invertebrates inside and outside the microsites. Thus, 100% FBO treatment is mainly characterized by ecosystem engineers, predators and decomposers organisms while 50% FBO treatments are characterized by predators like spiders or coleopteran. Finally, the composition of soil macro-invertebrates in T4 is dominated by phytophagous organisms like heteroptera and generalist decomposers like cockroaches. Soil conditions created by microsites are more favourable to organisms like isopoda, dermaptera and diplopoda that are more sensitive to changes on soil environment showing that FBO improve significantly soil quality.

IN

1

3.7 -5.4 2.6 -2.4

DERM. ORTH DIPLOP ANT CHIL EW DIPT. L

Effet microsite

IN

IN

T1 T3

T2

F2: 25.8%

SPIDERS SNAIL TERM

OUT

T4

1

LEPIDO. L.

F1: 35.2%

OUT

OUT

-1

-1 ISOPODA COL. A.

COL. L HIRU HOM

HET

DICTY

p=0.01 Effet traitement Figure 3 : a) PCA (Principal Components Analysis) on abundance and diversity of soil macro-invertebrates populations. T1: 100% FBO; T2 and T3: 50% FBO; T4: Conventional. B) Correlation circle showing the distribution of macro-invertebrate taxa. Taxa surrounded with an orange-coloured line are associated to T1, those with a blue-coloured line are associated to T2 and T3 and the yellow-coloured line surrounds taxa associated to T4.

Conclusions FBO allows a soft transition towards organic production systems. Tea quality and yield were sustained in the early phases of the experiment and soil macro-invertebrates

11

communities were deeply modified with immediate effects on soil physical properties. Better soil quality will lead soil system to better resist to natural or induced perturbations. The trend observed on soil macro-invertebrates indicates that the more positive effects observed inside the microsites soon extend to the soil outside the microsites improving progressively soil and tea quality. Besides the increase of tea quality, the elimination of mineral fertilizers and pesticides input will let the produced tea to get an organic label which will be directly related with its commercial price.

12

Bio organic Fertilization (FBO) improve soil structure Report: Elena Velasquez

Introduction Aggregate properties determine the macroscale structural condition of the soil. Macroaggregation is a highly dynamic attribute of soils that is claimed to have a significant impact on their ability to store C and conserve nutrients.

The aggregates are primarily formed by biological and physical processes and are responsible for soil structure. Among the processes involved in the formation of aggregates we can cite wetting and drying, freezing and thawing cycles, other temperature changes, cultivation, plant growth and earthworm activity.

The earthworms fragment organic matter and make major contributions to recycling the nutrients it contains, they modify soil structure, water movement, nutrient dynamics, and plant growth, their presence is usually an indicator of a healthy system. Earthworms perform several beneficial functions: stimulate microbial activity, mix and aggregate soil, increase infiltration, improve water-holding capacity, provide channels for root growth, bury and shred plant residue. In the FBO method earthworms, in association with additions of organic matter, increase plant productivity and create a stable soil structure.

We used a visual method of evaluation of soil aggregation validated across a wide range of sites in Nicaragua, Colombia, France, Brazil, Guyana and China, to evaluate the state of aggregation of the soil in the different treatments.

Material and methods Assessment of soil morphology The technique used here is derived from the Topoliantz et al (2000) “small volume” approach. At each location, 25x25x30 cm monoliths have been dug out for macroinvertebrate sampling. A small block of soil (10x10x10cm) was collected and separated by hand into macroaggregates and a few other items: Biogenic aggregates

13

Produced by macro-invertebrates (mainly earthworms and termites plus Coleopteran larvae, Diplopoda) were separated among three size classes, small (biogenic small: bs