12月5日th 是世界土壤日. 在这里, 地理位置 讲师 Alan Dixon博士 讨论保护性农业日益重要的意义, 而且 how recent collaborative research in Malawi is shedding light on its important contribution to sustainable development.
In recent years there has been much interest across sub-Saharan Africa in ‘conservation agriculture’, a farming technique described by the UN’s Food 而且 Agriculture Organisation as “… an approach to managing agro-ecosystems for improved 而且 sustained productivity, 增加利润和粮食安全, while preserving 而且 enhancing the resource base 而且 the environment”. 换句话说, conservation agriculture offers a means of achieving sustainable development; it can restore the environment while also improving the livelihoods of farmers. It does this through the integration of three key farming principles:
1)采用 免耕, which avoids mechanical soil disturbance 而且 hence promotes a loose soil structure that enhances water infiltration, 有机物质, 和作物根系生长;
2)维护 永久有机土壤覆盖层, which means using cover crops or mulching to protect topsoil against erosion, while also creating a micro-environment that supports beneficial soil organisms;
3)作物 多样化和轮转 意味着在不同的时间种植一系列作物, 促进营养循环, 土壤结构的多样性, 并降低害虫和疾病的风险.
保护性农业的吸引力, 特别是发展慈善机构和非政府组织, lies in its simplicity; it doesn’t rely on expensive machinery or h而且outs of fertiliser or pesticide, 理论上讲, 一次训练, 农民可以从中受益并变得自力更生. 这在马拉维这样的国家尤其重要, where approximately 70% of the population live below the poverty line 而且 11 million people are dependent on subsistence agriculture for their survival. 在这里, the already fragile 而且 vulnerable agricultural l而且scape is threatened by climate change, 而且 many areas have experienced severe l而且 degradation characterised by declining soil fertility 而且 soil erosion (up to 39 tonnes per hectare per year).
在大发软件下载官网，大发软件下载一直在与一个非政府组织合作, Tiyeni马拉维, to examine how conservation agriculture practices can make a difference to the lives of subsistence farmers. Tiyeni在奇切瓦语中的意思是大发软件下载去的, has developed a specific type of conservation agriculture called ‘deep-bed farming’ (DBF) which since its introduction in 2005 has spread to over 20,全国有1万户农民.
DBF结合了许多保护性农业的原则, but its key innovation is the manual break-up 而且 tillage of compacted soil prior to cultivation. 不像主流保护性农业禁止耕作, DBF tillage is also actively encouraged every five years in order to maintain the loose soil structure. DBF also includes the construction of raised agricultural beds that are bordered by ditches that collect 而且 store water. These beds are constructed in terraces that follow the contour of the l而且, 而且 each ditch is closed at the end of each farming plot to prevent soil 而且 water loss. 同时对农民进行土地管理技术的培训, Tiyeni also teaches farmers how to make organic manure from readily available animal 而且 crop waste. The simplicity 而且 accessibility of DBF seems to have been a major factor influencing its adoption among farmers, but does DBF actually produce win-win outcomes for people 而且 the environment?
简短的回答是“是的”. Our recent research suggests that those farmers who adopt DBF experience a doubling 而且 sometimes tripling of maize yields compared to those who practice conventional farming techniques. 这不仅改善了粮食安全, but it also means farmers can generate an income from the sale of surplus crops, 而且 this money is often used for children’s school fees or equipment such as bicycles or mobile phones.
环境, our research also suggests that DBF has significant benefits over conventional farming; it reduces soil erosion by 50%, 储存更多水分, 提高土壤养分的有效性. Unsurprisingly, underpinning all these benefits was the the 5-year soil tillage regime.
到时耕作还是不耕作? Academic debate continues within conservation agriculture circles about the advantages 而且 disadvantages of each, 而且 indeed whether ‘deviant’ practices like Tiyeni’s DBF can truly be considered conservation agriculture. While some would suggest the importance of maintaining 而且 upholding an agreed set of conservation agriculture principles that can be applied consistently around the world, others might argue the need to move beyond a prescriptive one-size-fits-all approach – 而且 instead consider how broad principles can be interpreted, 测试和适应每个独特的农业环境. 马拉维自给自足的农民, 当然，真正重要的是什么, 是有效的, 而且 what helps them achieve food security 而且 resilience to climate change. Tiyeni的DBF就是这样做的.
如欲了解更多有关保护性农业的资料，请浏览 Tiyeni的深床农业. 阅读更多有关 大发软件下载官网的研究 在这个领域.
Find out more about the 科学与环境学院 at Worcester