Integrating Forage Into Traditional Farming System in the Western Loess Plateau, China--Challenges, Constraints and the Future
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University of Kentucky UKnowledge XXI International Grassland Congress / VIII International Grassland Congress Proceedings International Rangeland Congress Integrating Forage into Traditional Farming System in the Western Loess Plateau, China--Challenges, Constraints and the Future Yuying Shen Lanzhou University, China Murray Unkovich The University of Adelaide, Australia Zhibiao Nan Lanzhou University, China Follow this and additional works at: https://uknowledge.uky.edu/igc Part of the Plant Sciences Commons, and the Soil Science Commons This document is available at https://uknowledge.uky.edu/igc/21/10-1/2 The XXI International Grassland Congress / VIII International Rangeland Congress took place in Hohhot, China from June 29 through July 5, 2008. Proceedings edited by Organizing Committee of 2008 IGC/IRC Conference Published by Guangdong People's Publishing House This Event is brought to you for free and open access by the Plant and Soil Sciences at UKnowledge. It has been accepted for inclusion in International Grassland Congress Proceedings by an authorized administrator of UKnowledge. For more information, please contact [email protected]. Multifunctional Grasslands in a Changing World Volume Ⅱ 瞯 1 85 瞯 ] Integrating forage into traditional farming system in the western Loess Plateau , China － Challenges , constraints and the future Y uying Shen1 , Murray Unkov ich2 , Zhibiao N an1 1 College o f Pastoral A griculture Science and Technology , L anz hou University , Key L aboratory o f Grassland A gro‐ Ecosystems , L anz hou 730020 , China , E‐mail : yy .shen＠ lz u .edu .cn 2 School o f Earth and Env ironmental Science , University o f A delaide , Roseworthy SA 5371 , A ustralia Key points : １ ‐ . Integrated systems involving grain crop forage and ruminant animals may strike a balance between the imperatives of ２ increasing productivity and inco‐me whilst reducing soil erosion in the Loess plateau ３ . Significant achievements in crop forage integration have been made in the region ４ . Small scale households need starting capital for livestock production . Relatively steady government policy would help the integration system to further develop Key words : Medicago sativ a , forage legume farming system , resource use efficiency Introduction ４００ ０００ ２ １７ ８０‐８８％ １T６h９e１Loess Plateau in China , covers about , km ov１e９r９０ provinces and dryland farming accounts for of the total . million ha of arable ６la０n０d０ in the region ( Li et al . , ) . The region has a long farming history and some parts have been cultivated for around years . Severe soil erosion together with high r３a７i２n０fall var‐２iabilit‐１y require constant １m２a０na０g０e０ment re‐２spons‐１es . It has been reported that １s９o９il９erosion in the region can range from t km year to a maximum of , t km year , the highest in China ( Liu , ) . For years , subsistence６f８arming systems generated limited cash income for the regio７n０s％farmers . Official figures have shown that the r１eg０ional GDP is million RMB yuan , with a net income per capita only of the country�s average , furthermore some million people are considered to be living in conditions of poverty within the region . Together these factors highlight the retarded economy and vulnerable ecological environment of the Loess Plateau . An integrated farming system including grai２n００, f５orage , cash crops and livestock has been proven to be suitable for sustainable development and food security ( Entz , et al ) . Experiences from other countries around the world such as India , Uruguay and Argentina provide successful examples of different integrated farming systems which have accomplished sustainability on both environmental and economic fronts . The objective of this paper is to show potential ways to respond to the problems existing in the region . Given the unique nature of the Loess Plateau , we would like to show what sort of constraints exist to further implementation of integrated farming systems , and future prospects for integrated farming systems in the region . Food security insuring ４０００ Livestock systems have been a major component in agricultural systems as far back as years ago in the Loess Plateau . Liv１es９t５o０ck and cultivation systems have changed over time , frequently driven by food demand and population pressure up until late �s Great２０L０e７ap Movement , when monoculture grain systems became the dominant system , and continue to be so４t３o０day ( Da‐n１ g et al , ) . These monoculture grain２s０y０s７tems have contributed to low soil fertility , with wheat yields as low as kg .ha in s２o０m１０e of the growing areas ( Yang , ) . Feeding the population３６h０as always been the first priority in China . By the end of , th１e４０population in the Loes４s０P０lateau is predicted to be arou２n０d０７ million . It is estimated that grain demand for the region will be thousand t based on kg per capita ( Yan & Lei , ) . Meanwhile , the limited land resources available for ar１a２b７l５e farming in th６e６r９egion has been a struggle faced for cen３t６uries , to highli２g０h０t５this , wh１０il５e China� s popu１l９a６ti１on has increased to ０ １m１ illion from million , arable land has decreased to million ha in , from million ha in , with an ave２r０a０g６e of . ha per capita . This is much lower than the average of other developing countries and of the world average ( Yang , ) . ‐ ２F０o０r５thousands of years l‐ivestock production in most parts of China has been dominated by a pig grain crop system ( Ren et al , a) . Within this pig gr‐ain s‐ystem , humans and pigs share the same grain supply , resulting in increased overall grain requirement . With a forage crop ruminant livestock system , for cut or carrying utilizati‐on , r‐uminant livestock ( cattle , sheep and goat) are fed by forage crops and the food grains consumed by humans ‐Such forage crop ruminant liv２e０s０t５ock systems have been recognized as a major direction for agricultural development for north western China ( Ren et al , b) . The sy‐stem incorporates such２０f０e５atures as better water use efficiency , and environmental friendliness and sustainability than pig crop systems ( Qian , ) , and can take fu２l０l ％advantage of the nutrition efficiency in agriculture , reduce the pressure on food security and optimize food structure . If of total land are allocated for forage production within a farming system , total primary vegetative production can be two times higher than grain production o２n０l０y５, one third of pig production could be replaced by the herbivores , and production efficiency is further improved ( Ren et al , ) . The ra摧tio of pigs to herbivore livestock in the region would be close to that seen in Europe and North America . The whole of China s grain output has grown steadily , with meat and milk yield particularly increasing in recent years , suggesting that grain production proportion could be reduced by Grasslands/Rangelands Production Systems——— Integration of Crops , Forage and Forest Systems 瞯 1 86 瞯 Multifunctional Grasslands in a Changing World Volume Ⅱ ] ７ planting forage crops without affecting protein production as protein output of a legume forage is times that in cereal grain . Figure 1 Grain output in total , grain consumption per cap ita and meat yield per capita in China (Ren et al , 2005) Environmental perspective Soil fertility , erosion and silta‐tion p‐roblems are high priority environmental issues for the region . Research in the region has shown that diverse f‐orage grain rotations can deliver increased protection of land and water resources , and increase the productivity and well being of rural communities by raising productivity whilst reducing soil erosion . Primary productivity on the Loess Plateau is driven by rainfall ( within temperature constraints) , but the water is frequently used inefficiently , often with high runoff and erosion resulting in lost production . A fundamental research goal is to increase resource use efficiency within farming systems , raising productivity whilst reducing soil erosion . Forage crops can be key elements of these new farming systems . Compared with grain crops , wheat in particular , both annual or perennial forage crops have better productivity during the autumn , thus , rainfall use efficiency and radiation use efficiency for forage are Medicago sativ a relatively higher . In recent years , lucerne ( ５１９ L ) has become２o０n０e５ of principle legumes in３１t％he region with２０h０i１gh yield and good quality fodder , it�s planting area reached thousand ha in in Gansu Province , a increase in . ３０％ ～ ３S５oi％l N fertility is another indicator of env３i‐ronmental quality . It was reported that N fertilizer use efficiency was only , with excessive accumulation of NO N in the soil profile below the crop rooting d５e０p０th , this is due largely to unbalanced and excessive use of N fertilizers within grain mon２o０c０u６ltures , and application rates of kg ha/ yr , five time over the crop requirement . i２n０m０７any places was reported ( Yang , ) . On the other hand , unfertile sloping land , did not receive fertilizer N ( Yan & ‐Lei , ) . However , lucerne has significant beneficial impacts on soil nitrogen use and carbon sequestration . Within a lu３cerne wheat rotation production system , residual soil N after１a lucerne phase was available for following crops , reducing NO N leaching and waste and increasing N use efficiency ( Table ) . Table 1 G rain yield , N content , W UE , N balance f or w inter w heat crop w ithin lucerne‐w inter w heat rotation system ( X i f eng , Qingyang city , Gansu) . V alues f ollowed bythe same letter w ithin a column are not signi f icantly di f f erent by analysis o f v ariance . Wheat N rate Grain N in WUE N input N output N budget grow th year for wheat yield grain in g‐１rain ‐１ ( kg/ ha) ( kg / ha) ( kg / ha) after lucerne ( kg / ha) ( t/ ha) ( kg / ha) ( kg ha mm ) ０ ３ １５ ３ ３４ ６ ３ ４ ８ １１２ ４３ ‐１０７ ６３ The first year . a . a . 厖葺�＃牋 １３８ ３ ７１ ４ ４３ ７ ５ １４２ ８ １６１ ２０ ‐１８ ４０ . ab . b . 厖破＃6敂挝 ０ ３ ３５ ３ ３４ ６ ０ ４ ８ ５５ ９０ ‐５１ １０ The second year . a . 破亮＃n牋 １３８ ３ ９８ ４ ４３ ７ １ １４２ ８ １２１ ０７ ２１ ７３ . b .