whereas as mob of 2,500 sheep is spreading nearly $800/day (assuming 5 sheep equals 1 cow). Over a year that balloons out to $235,000 (500 cows) and $292,000 (2,500 sheep) worth of nutrients returned to the soil. Again, the annual fertilizer bill of most livestock properties pale in comparison.

Intensive vs Non-Intensive Production While we can calculate the financial value of the biological capital deposited by livestock and earthworms, what about whole production systems? Does the value of biological capital differ between production systems? Again using fertilizer prices as the basis of financial value and the estimates from Whitehead’s book, a quick, crude comparison between intensive dairying and beef production (Tables 3&4) can be calculated. These tables relate to United Kingdom cattle grazing and assume 8,800 lb DM/acre/yr (10,000kgDM/ha/yr) of pasture leaf and 4,400 lb DM/ha/yr (5,000kgDM/ha/yr) of root material decomposes in pasture annually. The dairy system incorporates high fertilizer use whereas the beef system incorporating grass clover swards with no fertilizer. The element values are based on 2009 New Zealand fertilizer prices. For this article, the Total $ value calculations only involve what is returned to the soil by animal and plant, whereas the Gain $ value includes all nutrient contributions to and emissions from the soil as calculated by Whitehead. Any mineral excreta return higher than intake is due to animals eating soil. Annually, sheep and cattle can consume up to their own body weight of soil. By adding up the Total$ rows it’s no surprise the dairy system returns a higher market value of nutrients (NZ$2060.57) back to the soil reflecting more inputs. Yet when adding up the Gain$ rows the overall net gain in biological capital is minimal (NZ -$0.59). In comparison, the Total$ grass and clover return is half that of dairying (NZ$ 964.97) but its biological capital (Gain$) increases annually by NZ$73.36/acre (NZ$183.40/ha), nearly a 20% return on what is invested. That equates to an appreciation in value of $36,680 across a 500-acre (200-ha) property (versus $118 decline for the dairy system on the same area).

Calculating the Economics of Biodiversity Whitehead comments that as production systems become more intensive and nitrogen fertilizer use increases, pasture species reduce, leading to

increased leaching of nutrients and a reduction in all wildlife. The loss of wildlife and the free services these organisms provide farmers has to do with the health of the soil. In comparing beef and dairy farming systems these figures point to why there are so many pasture and animal issues with intensive dairy farming. While the market value of plant and animal waste reinvested back into soil is higher with dairy, the nature of the investment is so unbalanced it doesn’t accrue or create any biological capital. In business terms they’ve increased the cash flow without growing the capital base thereby compromising the potential net worth of the business. Of course in real (non-biological) commercial terms the extra productivity cashes up the dairy farmer and brings down the mortgage faster. However, this will come at the expense of a higher overdraft to correct all the problems associated with high input farming and depleted soils. If both enterprises only covered its costs and wasn’t profitable, the beef enterprise would be ahead because the accruing biological capital would buffer the wet, dry, and cold leading to longer growing seasons. This means more grass for fewer dollars invested. However, as the tables forewarn, the disappearance of major nutrients like calcium and magnesium (which are the building blocks of soils and plants) signal that even beef properties will eventually fail unless these

deficiencies are corrected by soil or animal nutrition programs. In estimating the market value of biological capital these crude calculations reflect the real economics of biodiversity to farming systems. Certainly the contribution earthworms make by enhancing the nutrient qualities of the soil and building biological capital has positive effects on the production system. Even the value of dung and urine returned by livestock is a significant contribution in market terms to the business. As farmers begin measuring biological agriculture with greater professionalism there will be a deeper connection between biological and financial capital. John King is a Holistic Management Certified Educator living in Christchurch, New Zealand. You can contact him through www.succession.co.nz John wishes to acknowledge the assistance of Australian Holistic Management Certified Educator Jason Virtue with this article. This article was first printed in ACRES USA. One US$ equals NZ$1.45. Number 133

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