Abstract:
:For centuries, traditional agricultural systems have contributed to food and livelihood security throughout the world. Recognizing the ecological legacy in the traditional agricultural systems may help us develop novel sustainable agriculture. We examine how rice-fish coculture (RF), which has been designated a "globally important agricultural heritage system," has been maintained for over 1,200 y in south China. A field survey demonstrated that although rice yield and rice-yield stability are similar in RF and rice monoculture (RM), RF requires 68% less pesticide and 24% less chemical fertilizer than RM. A field experiment confirmed this result. We documented that a mutually beneficial relationship between rice and fish develops in RF: Fish reduce rice pests and rice favors fish by moderating the water environment. This positive relationship between rice and fish reduces the need for pesticides in RF. Our results also indicate a complementary use of nitrogen (N) between rice and fish in RF, resulting in low N fertilizer application and low N release into the environment. These findings provide unique insights into how positive interactions and complementary use of resource between species generate emergent ecosystem properties and how modern agricultural systems might be improved by exploiting synergies between species.
journal_name
Proc Natl Acad Sci U S Aauthors
Xie J,Hu L,Tang J,Wu X,Li N,Yuan Y,Yang H,Zhang J,Luo S,Chen Xdoi
10.1073/pnas.1111043108subject
Has Abstractpub_date
2011-12-13 00:00:00pages
E1381-7issue
50eissn
0027-8424issn
1091-6490pii
1111043108journal_volume
108pub_type
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