Global achievements in soil and water conservation:The case of Conservation Agriculture

In response to the dust bowls of the mid-thirties in the USA,soil and water conservation programmes involving reduced tillage were promoted to control land degradation,particularly soil erosion.The farming and land management practices that were considered to adequately address soil and water conservation objectives were based on no-till seeding and maintenance of soil mulch cover.This collection of practices led to what became known as conservation tillage,although no-till systems by definition avoid soil disturbance by no-till direct seeding,and maintain an organic mulch cover on the soil surface.This article is an overview of achievements in soil and water conservation on agricultural lands through the experience derived from the adoption and spread of Conservation Agriculture(CA)world-wide.CA is an agro-ecological approach to sustainable production intensification.It involves the application of three inter-linked principles that underpin agricultural production systems based on locally formulated practices:(i)permanent no or minimum mechanical soil disturbance,which in practice entails direct seeding through mulch into no-till soils;(ii)maintenance of soil cover with crop residues and green manure crops,particularly legumes;and(iii)diversified cropping system involving annuals and perennial in rotations,sequences and associations.In 2011,CA had spread over 125 million hectares(9%of the global cropped land)across all continents and most agro-ecologies,including small and large farms.In addition,there is a significant area of CA orchards in the Mediterranean countries.CA is now considered to be a practical agro-ecological approach to achieving sustainable agriculture intensification.It offers environmental,economic and social advantages that are not fully possible with tillage-based production systems,as well as improved productivity and resilience,and improved ecosystem services while minimizing the excessive use of agrochemicals,energy and heavy machinery.While there are challenges to the adoption of CA,there is also increasing interest from producers,the civil society,donors and private sector institutions to further promote and service the uptake and spread of CA globally.

Current status of adoption of no-till farming in the world and some of its main benefits

In 1999 no-tillage farming,synonymous of zero tillage farming or conservation agriculture,was adopted on about 45 million ha world wide,growing to 72 million ha in 2003 and to 111 million ha in 2009,corresponding to an growth rate of 6 million ha per annum.Fastest adoption rates have been experienced in South America where some countries are using no-tillage farming on about 70%of the total cultivated area.Opposite to countries like the USA where often fields under no-tillage farming are tilled every now and then,more than two thirds of the area under no-tillage systems in South America is permanently not tilled;in other words once adopted,the soil is never tilled again.The spread of no-tillage systems on more than 110 million ha world-wide shows the great adaptability of the systems to all kinds of climates,soils and cropping conditions.No-tillage is now being practiced from the artic circle over the tropics to about 50ºlatitude south,from sea level to 3,000 m altitude,from extremely rainy areas with 2,500 mm a year to extremely dry conditions with 250 mm a year.No-till farming offers a way of optimizing productivity and ecosystem services,offering a wide range of economic,environmental and social benefits to the producer and to the society.At the same time,no-till farming is enabling agriculture to respond to some of the global challenges associated with climate change,land and environmental degradation,and increasing cost of food,energy and production inputs.The wide recognition of no-till farming as a truly sustainable system should ensure the spread of the no-till technology and the associated practices of organic soil cover and crop rotation,as soon as the barriers to its adoption have been overcome,to areas where adoption is currently still low.The widespread adoption globally also shows that no-tillage farming cannot any more be considered a temporary fashion or a craze;instead largely through farmers’own effort,the system has established itself as a farming practice and a different way of thinking about sustainable agro-ecosystem management that can no longer be ignored by scientists,academics,extension workers,farmers at large as well as equipment and machine manufacturers and politicians.

Assessing potential protection effects on commercial fish species in a Cuban MPA

Cuba has been leading marine protected area(MPA)designation in the Caribbean region to ensure conservation of its valuable marine ecosystems.Yet,an efficient monitoring program for MPAs is still to be implemented and will benefit from pre-existing information.The highly regulated MPA of Punta Francés National Park is one of the first Cuban MPAs and was established mainly to protect species and ecosystems for tourism purposes.Monitoring of protection effects on commercial fish species was lacking in this MPA.This study aimed at increasing local scientific knowledge by providing a baseline study about the most commercially fished families(Haemulidae,Lutjanidae and Serranidae)around Punta Francés MPA.Data collected represent only a limited period but can be used as a base point to support future monitoring.Fish abundance in number and biomass,and size were collected to test for differences between inside and adjacent areas outside the Punta Francés MPA,in different coral reef types.The main result of this study was the significantly larger size and biomass of snappers and groupers outside the MPA where intense fisheries occur.An observation consistent with a large spawning aggregation was also recorded outside the MPA.Even with a limited set of data,these results suggest that,at least temporarily,the most targeted species[and sizes]are still highly vulnerable to fisheries.Relevant habitats in the adjacent area,that are apparently missing within the MPA,may support some of the results found.Extending the limits of the Punta Francés MPA to include those habitats outside may be critical to ensure the effectiveness of this MPA in contributing to protect the most commercial species of the region.This should be done together with efficient fisheries management measures in the region,such as the significantly increase of minimum legal sizes and temporal closures during spawning migrations.