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1.
Large-scale, energy-intensive, specialized production systems have dominated agricultural production in the United States for the past half-century. Although highly productive and economically successful, there is increasing concern with unintended negative environmental impacts of current agricultural systems. Production systems integrating crops and livestock have potential for providing additional ecosystem services from agriculture by capturing positive ecological interactions and avoiding negative environmental outcomes, while sustaining profitability. A diversity of ecologically sound integrated crop-livestock systems have been and can be employed in different ecoregions: sod-based crop rotations, grazing cover crops in cash-crop rotations, crop residue grazing, sod intercropping, dual-purpose cereal crops, and agroforestry/silvopasture. Improved technologies in conservation tillage, weed control, fertilization, fencing, and planting, as well as improved plant genetics offer opportunities to facilitate successful adoption of integrated systems. This paper explores the use and potential of integrated crop-livestock systems in achieving environmental stewardship and maintaining profitability under a diversity of ecological conditions in the United States.  相似文献   

2.
The intensification of agriculture in Europe has contributed significantly to the decline of mixed crop-livestock farms in favour of specialised farms. Specialisation, when accompanied by intensive farming practices, leaves farms poorly equipped to sustainably manage by-products of production, capture beneficial ecological interactions, and adapt in a volatile economic climate. An often proposed solution to overcome these environmental and economic constraints is to recouple crop and livestock production via cooperation between specialised farms. If well-managed, synergies between crop and livestock production beyond farm level have the potential to improve feed and fertiliser autonomy, and pest regulation. However, strategies currently used by farmers to recouple dairy livestock and crop production are poorly documented; there is a need to better assess these strategies using empirical farm data. In this paper, we employed farm surveys to describe, analyse and assess the following strategies: (1) Local exchange of materials among dairy and arable farms; (2) Land renting between dairy and arable farms; (3) Animal exchanges between lowland and mountainous areas; and (4) Industrially mediated transfers of dehydrated fodder. For each strategy, cooperating farm groups were compared to non-cooperating farm groups using indicators of metabolic performance (input autonomy, nutrient cycling and use efficiency), and ecosystem services provision. The results indicate that recoupling of crop and dairy production through farm cooperation gives farmers access to otherwise inaccessible or underutilised local resources such as land, labour, livestock feed or organic nutrients. This in turn leads to additional outlets for by-products (e.g. animal manure). Farmers’ decisions about how to allocate the additional resources accessed via cooperation essentially determine if the farm diversifies, intensifies or expands operations. The key finding is that in three of the four crop-livestock integration strategies assessed, these newly accessed resources facilitated more intensive farming practices (e.g. higher stocking rate or number of milking cows per hectare) on cooperating dairy farms relative to non-cooperating, specialised dairy farms. As a consequence, cooperation was accompanied by limited environmental benefits but helped to improve resource use efficiency per unit of agricultural product produced. This article provides a critical step toward understanding real-world results of crop-livestock cooperation beyond the farm level relative to within-farm crop-livestock integration. As such, it brings practical knowledge of vital importance for policy making to promote sustainable farming.  相似文献   

3.
Australian farming systems have an enduring history of crop–livestock integration which emerged in the face of high climate variability, infertile soils and variable landscapes. Ley farming systems with phases of shorter annual legume pasture phases with cereal crops predominate but, emerging sustainability issues and the need to manage risk is driving ongoing innovation in crop–livestock integration. We discuss the recent evolution of selected innovations that integrate crop and livestock production and their impacts on farm productivity, sustainability and business risk. Dual-purpose use of cereals and canola (Brassica napus) for forage during the vegetative stage while still harvesting for grain is now practiced throughout southern Australia's cropping zone. This practice provides risk management benefits, diversifies crop rotations, reduces pressure on other feed resources and can significantly increase both livestock and crop productivity from farms by 25–75% with little increase in inputs. Sacrificially grazing crops when expected grain yield is low and/or livestock prices are attractive relative to grain provides further flexibility in crop–livestock management systems vital for business risk management in a variable climate. Replacing annual pastures with perennial pasture phases in rotation with crops can provide a range of benefits including improved hydrological balance to reduce dryland salinity, subsoil acidification and water-logging, provide a management tool for herbicide-resistant or problem weeds, improved soil nutrient and carbon stocks as well as increased livestock productivity by filling feed gaps. In some environments, integration of perennial forages in mixtures with cropping, such as alley cropping and inter-cropping, also provide options for improving environmental outcomes. These practices are all innovations that provide flexibility and enable tactical decisions about the mix of enterprises and allocation of land and forage resources to be adjusted in response to climate and price. We discuss these innovations in the context of the emerging constraints to crop–livestock integration in Australia including the continuing decline in labour availability on farms and increasing management skill required to optimise enterprise profitability.  相似文献   

4.
Chemical fertilizer use has contributed significantly to increased global food output in the past half century, especially in climatically favourable regions of the world. However, in drier agro‐ecological zones, such as in West Asia and North Africa (WANA) with a Mediterranean‐type climate, fertilizer use has been low but has increased rapidly in the past few decades. Chemical fertilizer use is now widely adopted in rainfed and irrigated agriculture. As elsewhere, fertilizer use is underpinned by concerns about biological and economic efficiency. Fertilizer use efficiency is central to the current concept of fertilizer best management practices (FBMP), which embraces right source, right place, right timing and right application method. In this brief review, we highlight such FBMP concepts as related to agriculture of the WANA region, with emphasis on the key nutrients for crop production. Rainfall has a dominant influence on dryland crop yields. Nitrogen (N) use efficiency increases with increasing rainfall and is influenced by crop rotation. Under rainfed conditions, modest N losses by volatilization can occur. Leaching losses are usually minimal. Phosphorus use (P) efficiency is higher with band application than with broadcasting. Balanced fertilization, especially involving potassium (K) and micronutrients, is fundamental to efficient nutrient use. Fertilizer efficiency is also influenced by soil test values and agronomic factors that influence crop yields, e.g. sowing date and varietal differences. Rational fertilizer application rates are guided by calibration–response trials. Effective fertilizer use in the region is also dictated by external factors such as government policies and a functioning extension service. In contrast to other regions of the world, environmental impacts from the overuse of fertilizers are relatively minor, while developments in fertilizer formulations that promote efficiency have yet to have impact. Despite the relatively low fertilizer use intensity in dryland areas such as the WANA region, the FBMP comprehensive approach is a logical framework within which to achieve the most efficient management and use of fertilizer in the region’s agriculture.  相似文献   

5.
苏州地区农作物种植结构调整的思路分析   总被引:3,自引:0,他引:3  
苏州地区农作物种植结构调整须遵循社会经济和农业发展实际状况,在实行最严格的耕地保护和稳定粮食综合生产能力基础上,结合本地特色,充分挖掘各种优势资源,积极发展高效农业、特色农业、创汇农业,加快农作物品种的更新、新技术的开发和应用,新型耕作和种植模式的探索、尝试,逐步提高农业产业化经营水平,提升农业整体效益。  相似文献   

6.
This paper reviews the knowledge on effects of climate change on agricultural productivity in Europe and the consequences for policy and research. Warming is expected to lead to a northward expansion of suitable cropping areas and a reduction of the growing period of determinate crops (e.g. cereals), but an increase for indeterminate crops (e.g. root crops). Increasing atmospheric CO2 concentrations will directly enhance plant productivity and also increase resource use efficiencies.

In northern areas climate change may produce positive effects on agriculture through introduction of new crop species and varieties, higher crop production and expansion of suitable areas for crop cultivation. Disadvantages may be an increase in the need for plant protection, the risk of nutrient leaching and the turnover of soil organic matter. In southern areas the disadvantages will predominate. The possible increase in water shortage and extreme weather events may cause lower harvestable yields, higher yield variability and a reduction in suitable areas for traditional crops. These effects may reinforce the current trends of intensification of agriculture in northern and western Europe and extensification in the Mediterranean and southeastern parts of Europe.

Policy will have to support the adaptation of European agriculture to climate change by encouraging the flexibility of land use, crop production, farming systems etc. In doing so, it is necessary to consider the multifunctional role of agriculture, and to strike a variable balance between economic, environmental and social functions in different European regions. Policy will also need to be concerned with agricultural strategies to mitigate climate change through a reduction in emissions of methane and nitrous oxide, an increase in carbon sequestration in agricultural soils and the growing of energy crops to substitute fossil energy use. The policies to support adaptation and mitigation to climate change will need to be linked closely to the development of agri-environmental schemes in the European Union Common Agricultural Policy.

Research will have further to deal with the effect on secondary factors of agricultural production, on the quality of crop and animal production, of changes in frequency of isolated and extreme weather events on agricultural production, and the interaction with the surrounding natural ecosystems. There is also a need to study combined effects of adaptation and mitigation strategies, and include assessments of the consequences on current efforts in agricultural policy to develop a sustainable agriculture that also preserves environmental and social values in the rural society.  相似文献   


7.
西藏农业生产结构分析及调整措施初探   总被引:5,自引:0,他引:5  
通过对西藏1995—2002年之间农业生产总值、种植业、畜牧业统计数据进行分析,发现西藏现有的农业生产结构存在如下问题:(1)种植业和畜牧业是西藏农业产值的主要组成部分,种植业和畜牧业发展不协调。(2)种植结构单一,以粮食作物为主,粮:经:饲=87:11:2,比例不合理。在粮食作物内部麦类作物占绝对比重,经济作物以油菜为主,均表现出明显的单一性。(3)畜群结构单一,为牛、羊为主的反刍类动物占绝对比重的草食型畜群结构,加大了西藏的草畜矛盾,不利于西藏畜牧业的健康快速发展。针对这些问题,笔者提出以下调整措施:(1)降低粮食作物尤其是青稞和小麦的播种面积,增加蔬菜、水果的种植面积。(2)推广粮草轮作制度,加强农牧结合。(3)增加猪、鸡的数量,逐渐以耗粮型与草食型相结合的畜群结构代替单一的草食型畜群结构。  相似文献   

8.
Combining crops and livestock within integrated crop–livestock systems (ICLS) represents an opportunity to improve the sustainability of farming systems. The objective of this paper is to analyse how agroecological principles can help farmers to redesign and improve the resilience, self-sufficiency, productivity, and efficiency of ICLS. Relying on case studies from Brazil and France, we examine how the transformation of two conventional, specialised systems into more integrated-production systems illustrates the different dynamics towards agroecological ICLS. The French case study, based on self-sufficient farming systems belonging to a sustainable agriculture network, highlights that cost-cutting management led to a win–win strategy comprising good economic and environmental performances. The farms decreased their dependence on external inputs and had only a limited loss of production. The past trajectories of the farms illustrate how increasing the interactions between subsystems improved the self-sufficiency and efficiency of the farms. The Brazilian case study compares slash-and-burn agriculture in the Amazonian region with the recovery of degraded grazing area by ICLS. A small increase in chemical inputs linked to a diversification of productions led to a large increase in production and a large decrease in environmental impacts (deforestation). The Brazilian case study also illustrates how the diversification of production increased the resilience of the system to market shocks. Reconstructing the links among soil, crops, and animals following agroecological principles could improve the different performances of ICLS. New agroecological ICLS, benefiting from diversified productions and increased interactions between subsystems, are likely to offset the trade-off between agricultural production and environmental impacts observed in current ICLS.  相似文献   

9.
生态家园建设与县域农村经济可持续发展   总被引:1,自引:0,他引:1  
方炎 《中国农学通报》2004,20(6):395-395
通过4县(旗、区)的问卷调查和案例分析,提出以农户为建设单元、以沼气为纽带的生态家园建设在达到一定的数量规模时,在县域范围内产生了一定的宏观效益。促进养殖业发展和种植业结构调整,有利于节约资源和改善生态环境,普及和推广农业技术,体现了高新技术对传统农业的改造,提高农民收入,促进农村小康建设。县级地方政府的积极参与和探索实践大大丰富了生态家园建设的内容,也影响了县级领导抓农业农村工作思路。  相似文献   

10.
针对四川丘陵区气候资源与农业类型,选择合理的生态循环农业模式,开展养分平衡管理,是实现四川丘陵区农业绿色发展的重要途径。本研究以四川蓬溪县为例开展实证分析,为川东丘陵区生态循环农业发展提供科学依据。结果表明,依据大田作物和果园目标产量、目标施N量,测算有机肥(沼液)的施用量,项目区产生的畜禽粪便和沼液可全部在区域内就近循环利用,化肥N替代率达31%~62%。依据项目区作物和果树种植基地的粪污有机肥替代测算,项目区域尚有一定的畜禽承载潜力。该种养循环模式结合当地的主导优势产业,使种养废弃物就近科学合理利用,减少了农业面源污染的风险。最后就川东丘陵区发展生态循环农业的经营机制和发展路径进行了分析,该模式为川东丘陵区开展循环农业提供参考。  相似文献   

11.
覆盖作物及其作用的研究进展   总被引:3,自引:0,他引:3  
在农作物种植系统中,田间杂草、土壤因素对作物的生长发育、产量和品质的影响一直都是农业领域关注的热点。大量使用化肥和除草剂可以达到作物增产、除草的目的,但其对土壤和环境造成的负面影响,严重制约了农业生产的可持续发展。种植覆盖作物是一种实现农业可持续发展的新策略,可以达到控制杂草、减少氮肥施用、改善土壤质量等目的。本文主要从覆盖作物的起源与发展过程、主要种类和作用及其种植制度等方面,总结了目前覆盖作物的研究进展及其在作物种植中的应用,以期为覆盖作物在我国农业生产中的研究与应用提供理论基础。  相似文献   

12.
For many years, we have seen an increasing specialization of agricultural systems and territories, with a clear separation between territories with very high animal densities and those devoted to the growing of annual crops. This development is explained by market and sector economic logic and has been reinforced by the availability of low-cost inputs and animal housing systems based on direct grazing not requiring straw. It has, however, also involved negative environmental impacts and, in some cases, the impoverishment of soil fertility, a loss of biodiversity, and excesses of N and P, leading to eutrophication and hot spots of ammonia emission in livestock-breeding territories. Having recapped the mechanisms behind the specialization of systems and territories, we examined the extent to which the development of innovative mixed-farming systems that reconnect livestock and crop production on various territorial scales (farm, district, region) can reduce the negative impacts of agriculture on the environment, produce valuable ecosystem services and achieve acceptable economic efficiency for farming enterprises. Examples from temperate regions will be used to show that mixed-farming systems increase the possibilities of better recycling of nutrients within systems, limiting recourse to the purchase of increasingly expensive inputs and safeguarding the biodiversity of agricultural ecosystems.  相似文献   

13.
In the subtropical region of Brazil, integrated crop–livestock systems (ICLSs) are characterized by the annual rotation of pastures and crops in a no-till system where the pasture component is used to produce either meat or milk. These systems focus on integration within the farm rather than between farms, being characterized by alternating cropping and pasturing in the same area. Independent of the crop rotations possible in a subtropical environment, the main integrated farming system found was rotation or succession of summer crops (Glycine max, Zea mays, Phaseolus vulgaris or Oryza sativa) with winter annual grazing grasses (mixed or solely Avena strigosa and Lolium multiflorum) or successive natural pastures.The high variability of crop yield in the Brazilian subtropics (due to climate extremes) as well as associated high costs and low prices has encouraged farmers to integrate livestock into their enterprises as a low-risk diversification option. Long-term experiments have demonstrated the benefits of crop–livestock integration with respect to many aspects of the soil–plant–animal system. There is evidence that such a system is not only a livestock–agriculture combination but also a unique system reaching a new complexity threshold, resulting in emergent properties with novel functionalities, some of which have yet to be investigated. In addition to greater environmental gains with less vulnerability, there are higher yields and more financial gain by the farmer, compared to that in the use of monocultures or non-integrated livestock farming. We conclude that ICLSs in Subtropical Brazil provide the opportunity for intensification with sustainability.  相似文献   

14.
为了对新疆南疆干旱区科学制定农业发展规划、促进农林牧协调发展和农业增效、农民增收提供决策依据。以新疆和田县为例,通过对农业产业发展现状及存在问题的分析,采用灰色线性规划方法,构建优化模型,进行农业产业结构及生产布局的优化配置和合理布局研究。优化结果表明:通过优化,种植业、林果业、畜牧业占农业总产值的比重分别由2009年的43%、38%、17%调整为33%、45%、19%,农业内部形成了以林为主、以农带牧、以牧促林、农林牧统筹协调发展的产业联动格局;种植业内部结构趋于合理,粮经草的种植比重由74:21:5调整为60:25:15;特色林果业中核桃、红枣、葡萄的优势地位得到巩固,种植面积占总面积的88%,"南核北枣"、"北葡"战略布局全面形成,南部乡镇核桃种植面积占72%,北部乡镇红枣和葡萄种植面积分别占89%和82%;畜牧业牲畜存栏头数达到77.31×104头(只),保持平稳增长,养禽出栏规模为103.8×104只,呈快速增长态势;农业综合效益明显增加,农业净产值达到11.55亿元,年均增长10%,农民人均农业纯收入达到5200元。表明农业产业结构和生产布局优化方案符合当地社会经济发展需要,且具有较强的科学性和可操作性,对当地农业结构调整具有实际指导意义。  相似文献   

15.
雷州半岛夏季休闲耕作制度初探   总被引:1,自引:1,他引:0  
为了探索适合雷州半岛推广的休耕制度,为促进当地耕作制度的改革提供理论参考,本研究分析了雷州半岛的自然环境条件、农业生产现状及其存在的问题:自然灾害严重;连作,病虫害严重;部分农作物产品上市期与其他地方同类农作物产品的上市期重叠,致使农民生产经济效益不高等。由此认为:雷州半岛具有得天独厚的热带气候资源,发展农业很有优势。但是,该地区农业生产也面临着很多限制因素,其耕作制度也存在很多问题。雷州半岛农业应以冬春季为主要生产季节,使其逐渐成为当地的农业主导季节,而在夏季则对其耕地实行休耕与培肥措施相结合,避免恶劣天气对作物生产的危害,也使农田得到休养生息、快速恢复和提升耕地生产力,推行“秋、冬种春收”的生产模式,有利于提高当地农业生产效益。  相似文献   

16.
柴达木盆地南缘农业气候资源变化特征分析   总被引:2,自引:1,他引:1  
为了给柴达木盆地南缘合理利用气候资源和农业生产可持续发展提供科技支撑,利用柴达木盆地南缘1961~2015年气温、积温、日照时数、降水量等资料,应用气候倾向率、气候趋势系数等统计方法,分析该区农业气候资源变化特征。结果表明:(1)柴达木盆地南缘热量资源呈增加趋势,年、季平均气温升高明显,冬季升温趋势最显著,年平均气温变化倾向率为0.49℃/10a,冬季平均气温变化倾向率为0.62℃/10a。≥0℃、≥10℃年积温变化倾向率分别为77.0℃/10a、102.5℃/10a,除都兰站外其余各地积温增加较明显;21世纪以来较60年代年相比平均气温升高2.1℃,≥0℃的年积温增加336.8℃,≥10℃的年积温增加416.3℃。(2)光照资源呈略减少趋势,日照时数年际变化幅度较小,减少倾向率为35.2h/10a,夏季减少较为明显,减少倾向率为16.7h/10a,21世纪以来与60年代相比日照时数减少155.9h。(3)降水资源呈略增加趋势,年降水量增加倾向率为6.0mm/10a,其中夏季增幅最明显,增加倾向率为4.0mm/10a,年降水量增幅地区间差异较大,都兰增加最多,平均每10年增加15.8mm,格尔木最小,平均每10年增加1.7mm。(4)农业气候资源变化对调整农业种植结构,发展设施、特色农业,增加产量有利;同时也易造成农业水分供需矛盾加剧、农作物病虫害增多、农业成本和投资增加等不利影响。  相似文献   

17.
针对湖南农业大省,农业废弃物种类多,量大面广的问题,本研究根据不同种类的农业废弃物资源与有机肥产品特点设计了5种处理利用模式:(1)鸡粪+秸秆制成有机肥用于果蔬茶;(2)牛粪+烟末制作有机肥用于粮食与经济作物;(3)蘑菇渣等废弃物制作有机肥;(4)尾菜+饼粕制作有机肥用于蔬菜基地;(5)鸡粪+返料制作有机肥用于经济作物。研究结果表明:上述农业废弃物处理技术模式具有明显的优势:降低废弃物消纳和企业生产的时空成本,避免二次污染,获得了更多的有机肥料资源。这些技术模式可复制、可推广,为不同地区、不同种类废弃物、不同规模企业提供了借鉴,解决了农业污染物就地处理的技术难题,对环境保护和农业可持续发展具有积极意义。  相似文献   

18.
Climatic conditions and hence climate change influence agriculture. Most studies that addressed the vulnerability of agriculture to climate change have focused on potential impacts without considering adaptation. When adaptation strategies are considered, socio-economic conditions and farm management are often ignored, but these strongly influence current farm performance and are likely to also influence adaptation to future changes. This study analysed the adaptation of farmers and regions in the European Union to prevailing climatic conditions, climate change and climate variability in the last decades (1990–2003) in the context of other conditions and changes. We compared (1) responses in crop yields with responses in farmers’ income, (2) responses to spatial climate variability with responses to temporal climate variability, (3) farm level responses with regional level responses and (4) potential climate impacts (based on crop models) with actual climate impacts (based on farm accountancy data). Results indicated that impacts on crop yields cannot directly be translated to impacts on farmers’ income, as farmers adapt by changing crop rotations and inputs. Secondly, the impacts of climatic conditions on spatial variability in crop yields and farmers’ income, with generally lower yields in warmer climates, is different from the impacts of temporal variability in climate, for which more heterogeneous patterns are observed across regions in Europe. Thirdly, actual impacts of climate change and variability are largely dependent on farm characteristics (e.g. intensity, size, land use), which influence management and adaptation. To accurately understand impacts and adaptation, assessments should consider responses at different levels of organization. As different farm types adapt differently, a larger diversity in farm types reduces impacts of climate variability at regional level, but certain farm types may still be vulnerable. Lastly, we observed that management and adaptation can largely reduce the potential impacts of climate change and climate variability on crop yields and farmers’ income. We conclude that for reliable projections of the impacts of climate change on agriculture, adaptation should not be seen anymore as a last step in a vulnerability assessment, but as integrated part of the models used to simulate crop yields, farmers’ income and other indicators related to agricultural performance.  相似文献   

19.
In arid and populated areas or countries, water shortage and heavy carbon emissions are threatening agricultural sustainability with food security severely, and becoming a major issue. It is unclear whether improved farming systems can be developed to tackle those issues through a sustainable agriculture. Here three farming practices that have proven to be essential and successful, which were: (a) crop intensification through strip intercropping, (b) water harvesting through conservation tillage; and (c) carbon sequestration through improved crop residue management options, were integrated in one cropping system. We hypothesize that the integrated system allows the increase of crop yields with improved water use efficiency, while reducing carbon emissions from farming. The hypothesis was tested in field experiments at Hexi Corridor (37°96′N, 102°64′E) in northwest China. We found that the integrated system increased soil moisture (mm) by 7.4% before sowing, 10.3% during the wheat–maize co-growth period, 8.3% after wheat harvest, and 9.2% after maize harvest, compared to the conventional sole cropping systems. The wheat/maize intercrops increased net primary production by 68% and net ecosystem production by 72%; and when combined with straw mulching on the soil surface, it decreased carbon emissions by 16%, compared to the monoculture maize without mulch. The wheat/maize intercrops used more water but increased grain yields by 142% over the monoculture wheat and by 23% over the monoculture maize, thus, enhancing water use efficiency by an average of 26%. We conclude that integrating strip intercropping, conservation tillage as well as straw mulching in one cropping system can significantly boost crop yields, improve the use efficiency of the limited water resources in arid areas, while, lowering the carbon emissions from farming. The integrated system may be considered in the development of strategies for alleviating food security issues currently experienced in the environment-damaged and water-shortage areas.  相似文献   

20.
It is widely accepted that our climate is changing due to the increasing atmospheric concentrations of the ‘greenhouse gases’, and these changes may exercise strong impacts on different economic sectors. In particular for agricultural systems, such a change may have significant impacts on crop yield, cattle breeding and related management practices. Accordingly, the economic viability of agricultural production systems in future scenarios is a main concern especially for policy-making purposes. Up until now, the impact of climate change on agriculture has focused on change in crop yield, whereas a ‘holistic’ approach, considering both benefits (in terms of direct economic income) and detrimental environmental impacts of agricultural practices (soil loss, nitrogen leaching, water balance) has not been considered. On these premises, the objective of the present article was to assess agricultural sustainability on a farm level in Tuscany (central Italy) under the climate change regime, considering both conventional and organic farming systems (CFS and OFS, respectively). In particular, an ecological–economic optimisation model was run for both the present and future scenarios to perform an integrated assessment of sustainability of CFS and OFS on the case-study farm.  相似文献   

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