Long Term Ecological Research of Agricultural Ecosystem
2006-2011(the first stage, completed), 2012-1017(the second stage, continued),2018-
(1) Taiwan Agricultural Research Institute
(2) Tainan District Agricultural Research and Extension Station
(3) Miaoli District Agricultural Research and Extension Station
(4) Tea Research and Extension Station
(5) Taiwan Forestry Research Institute
(6) National Taiwan University
(7) National Cheng Kung University
(8) National Chung Hsing University
To understand the impact of agricultural practice on the services of agricultural ecosystem, a long term systematic research should be conducted to monitor and evaluate the change of ecosystem services. The better agricultural practice might be proposed to reach the goal of agricultural sustainability and biodiversity conservation by the evaluation.
To search the best agricultural manage model with minimum input, subtropical agricultural long term ecological research (LTER) stations where built on 2006 were set to investigate the effects of different manage and cultivated systems to biodiversity, productivity, and environment. Treatments of manage systems contained both conventional agro-ecosystem (CA) with high chemical input as well as sustainable agro-ecosystem (SA) with low chemical input in different rotation systems. Field tractability, soil fertility, nitrogen leaching, production cost, disease severity of crops, pest and indicated insect, dynamic of weeds, and biodiversity index were collected on LTER stations, treatments of cultivated systems contained: (1) the field crop ecosystems of Agricultural Research Institute Chi-Ko branch farm (8.0ha) with lowland and lowland-upland rotation and Tainan District Agricultural Research and Extension Station Yuin-Lin branch station (7.0ha) with upland and lowland-upland rotation; (2) the orchard ecosystem of Agricultural Research Institute Chia-Yi branch litchi orchard (2.5ha); (3) three tea gardens (1.32ha) located at Ming-jian village of Tea Research and Extension Station.
Major results (the first stage)
1. Field crop
(1) In field crop areas, our results showed that sustainable agro-ecosystem could save carbon-cost because of the reduction of input of nitrogen fertilizer.
(2) Crop productivity, crop value, disease-control, and pest-control were similar between conventional (CA) and sustainable (SA) agro-ecosystem.
(3) Soil effective potassium was decreasing year after year at lowland-upland rotation area of sustainable agro-ecosystem in Chi-Ko branch farm.
(4) Moreover, the amount of nitrogen leaching and the composition of insect predators had no significant difference between CA and SA area.
2. Litchi orchard
(1) Biodiversity, population of insect predators and pests, and amount of nitrogen leaching in natural litchi orchard ecosystem (NE) were significantly higher than conventional litchi orchard.
(2) The disease severity had no significant differences between CA and NE treatments.
3. Tea garden
(1) Biodiversity was increased but the amount of nitrogen leaching was decreased significantly with the reduction of chemical input in Mingjian tea gardens.
(2) Productivity of organic ecological tea garden was only about 30% of conventional area, but the total output value was similar between the two treatments.
(3) In consequence, organic ecological manage might contribute to increase the unit tea price, conserve biodiversity, and protect environment and ecosystem.