Management of land, water, waste and productivity for a sustainable future

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1 EATING THE FUTURE Can we feed a burgeoning world population without compromising the sustainability of our planet? Management of land, water, waste and productivity for a sustainable future Ian Crute Agriculture and Horticulture Development Board Vitacress Conservation Trust Environment Debate 3 March 2010

2 Croplands Atlas Mountains, Morocco Alaska, USA Credit: BigFoto. < >

3 Manhattan, New York, USA Credit: Josh <

4 Scottish Highlands

5 Pennines, N. England

6 Somerset, England

7 A glimpse of the global picture in 2010 Population is estimated to be ca. 9.5 bn by 2050 (currently 6.5 bn) UN estimates a demand for 50% more food by 2030 and 100% by ,500 m ha out of the 8,540 m ha that can support plant life is used for cropping = 18% available land At least 15 m ha of land ha lost to agriculture annually (urbanisation; industrialisation) Agriculture uses 70% of available fresh water 2009 global cereal production = 2.2 bn tonnes (6% more than 2007 but 0.1bn tonne < 2008) Global cereal stocks increased to 500 m tonnes (80 days) from 2007 low point Demand could exceed 3 bn tonnes by 2025 Mean global wheat yield = ca. 2 tonnes per ha (UK = ca. 8 tonne per ha) 100 m tonnes of grain used for biofuel production (4.3% global production)

8 The last 50 years and the next 50? World population 3.0bn 6.5bn = 117% 9.5bn = 46% Area of cereals 650m ha 725m ha = 12%? [1 bn ha?] Yield per hectare 1.4 tonne 3.1 tonne = 121%? [4.6 tonne?] Kg grain per capita 300kg 350kg = 17% 350kg = 0%

9 I urge clear thinking about what land use influences: The size of the sink for carbon (cf Gt C in soil and vegetation vs. 750 Gt in atmosphere) GHG emissions Fresh water availability, distribution and quality Biodiversity Space for human habitation, communications, amenity use and recreation The renewable production of biomass (agriculture+forestry) for - Food Energy Construction Fibre Industrial products Forage (livestock)

10 Sustainable Intensification [a manifesto for future food security] Producing as efficiently as possible on the smallest footprint of land is the greenest (and most profitable) way to farm

11 Sustainable Intensification The primary objective of land use for agriculture is the efficient conversion of solar energy into varied and valued forms of chemical energy for utilisation by mankind. Some land is best used to produce forage for animals as intermediates in the energy conversion process. The energy conversion involves manipulation and management of the interaction between genotype (animal and/or plant) and the environment The requirement to do this consistently and predictably demands continuity of agro-ecosystem functions; this captures the temporal and renewable concept of sustainability. Maximising efficiency on the smallest necessary land area provides options to use non-agricultural land to achieve other objectives (which should not be confounded with the requirement to produce food and other agricultural products as efficiently as possible).

12 Current global land usage (Total = 13,400 M Ha) Desert/mountain/ice 34.4% Other crops 6.9% Forest & Savannah 30.5% Cereals 4.6% Pasture & Range 23.7% Ca. 22% wild = ca. 11% NPP Ca 10 M Ha (= 0.25%) non-agricultural land (mostly forest) cultivated per annum Ca 17 M Ha (= 1%) of agricultural land lost to erosion (5), salinisation (2) and urbanisation (10) per annum

13 Limiting factors for global plant productivity Water is one of the limiting factors we should and can manage Water resources in England and Wales current state and future pressures (2008) When we take population density into account...we actually have less water per person in South East England than...morocco and Egypt. Baldocchi et al SCOPE 62

14 Soil fertility + crop nutrition the foundation for agricultural productivity

15 The global significance of crop loss due to diseases, pests and weeds.

16 GHG emissions from well grown wheat ca 400 KgC0 2 e/ha (N, other ag chem, machinery, cultivations, spraying, harvesting) Waste = lost yield + wasted inputs (economic) and > emissions/tonne

17 17

18 Barley cultivars resistant to mosaic disease rym4 and rym5 resistance genes Gloucestershire site, aerial view resistant susceptible

19 Genetic resistance in action!

20 Genetic resistance in action!

21 The Harvesters Pieter Brueghel (1565)

22 Broadbalk yields, varieties and major changes 10 Introduction of: liming fungicides fallowing herbicides Wheat grain yield (t/ha) st wheat in rotation: FYM+spring N fertiliser Continuous wheat: FYM Best NPK PK+144 kg N Unmanured, continuous wheat

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24 LAND USE Forestry Bioenergy crops Grassland + livestock Semi-natural vegetation Arable crops RESOURCE MANAGEMENT Soils Water Genetic resources Husbandry/Agronomy Energy OUTCOMES [SERVICES] Increase food production Produce renewable energy Reduced GHG emissions Adapt to climate change Conserve biodiversity Preserve valued landscapes Provide durable livelihoods Managing an ecosystem Provide clean water

25 A clear acknowledgement of: anthropogenic ecosystem management may be helpful Humans control (anthropogenic) ecosystem functions and biodiversity as much as climate: Deforestation Habitat fragmentation Grazing Arable agriculture Urbanisation etc... Ellis and Ramankutty move beyond the urban + agriculture + wild model of ecosystems Ecosystem processes = f(c) where C = macroclimate (precipitation and temperature affected by latitude, altitude and circulation) Old thinking: Natural ecosystems with humans disturbing them Anthropogenic ecosystem processes = f(p,t) where P = population density and T = how land and resources are used New thinking: Human systems with natural ecosystems embedded within

26 Anthropogenic Biomes: Conceptual Model Wildlands Forested RangelandsCroplands Villages Urban & dense Ellis & Ramankutty, in press