Hi all, Since I posted my request for references on soil health, I have received several messages pointing to sources of references. Thanks to those who helped. There are interests from some netters on the replies I receive. I will post a summary privately at a later stage if the interest is from a rather limited number of people. It has never been clear to me the differences among the terms soil fertility, soil quality and soil health. Seems to me soil quality is the term coined long after soil fertility. If you look for references on soil quality using Current Content, Agricola, or Tree CD, you will get an ample amount of hits. I think people are starting to talk about soil health more recently. But the earliest reference on soil health dates back to 1948 (McIntyre, A.C. 1948. Why waste wood? Soil Conserv. 14(4) 75-78). (So far as I can find) Seems to me soil fertility has a narrower application, i.e., soil fertility=soil productivity. But is soil quality the same as soil health? Seems to me soil health is a level above soil quality, as soil quality is still more inclined towards the abiotic aspects of the soil, although most of the indices used for testing soil quality are biological. There is little integration. Soil health should play a more important role in integrating the different aspects of soil quality, e.g., take into consideration soil biodiversity. Two of the replies (see below) pointed me to people working on soil quality. Sometimes the term soil quality and soil fertility is interchangeably use by authors (e.g., Gregorich et al. 1994. Can. J. Soil Sci., 74: 367-385). Therefore, I would be interested in hearing your opinion regarding those confusions in terminology. Please post to the list, as I think there is interest from other netters. The other topic for discussion is that there have been many studies on soil quality, what uses have you find for those soil quality indices? That is, it is very difficult to define a cutting point for those indices whether a particular soil has low or high quality, except applying the indices to soils of the two extremes. I did not give a sufficient introduction to the project I am working on. Here is a more detailed description. Coarse woody debris (CWD) is an integral part of the forest ecosystems of the Pacific Northwest. CWD relates to nutrient cycling, soil development, and site biodiversity. The concern is CWD retention in the PNW forest ecosystems is being decreased due to increased log price and improved harvesting technology. Thus soil organic matter levels and site productivity may be reduced in the long term. Therefore we are interested in finding a biological index or (indices) as a guideline to estimate the amount of CWD retention required to maintain the optimal soil organic matter level. The method presently being explored is the procedure proposed by Harvey's group (Harvey et al. 1987. USDA For Serv Gen Tech Rep INT-225). They find that the optimal soil organic matter level is correlated with the highest ectomycorrhizal root tip numbers in forest ecosystem (Intermountain Region). We are testing their hypothesis in the PNW forests. Hope this helps a bit. Redards, Scott X. Chang ------------------------------------------ Date: Thu, 4 Jan 1996 20:42:40 -0600 From: Brian Needelman <needelma@uiuc.edu> To: xichang@unixg.ubc.ca Subject: Refs. on soil health reqest Hello, I am a graduate student at the Univ. of Illinois. I am working with the Illinois Soil Quality Initiative. I believe my advisers are some of the researchers you are referring to. We are also looking at biological indices with an emphasis on organic matter levels. However, our focus is only agricultural. A basic book on the text that has many references is: Defining soil quality for a sustainable environment. SSSA Special Publication no. 35. SSSA, Madison, WI. One of the objectives of our project is to screen potential soil quality indices for use in the state of Illinois. Our strictly biological indices include soil respiration, microbial biomass. We are experimenting with the use of the Biolog system to assess biodiversity, but this has its difficulties. We are also testing for mineralizable nitrogen and particulate organic matter in an effort to indicate long-term OM changes. There was an issue of the American J of Alternative Agriculture a few years ago dedicated to the topic. It is similar to the book cited above. I am interested in what you come up with. Let me know if you have anything more specific you would like references for or if you have any more questions on our methodology, etc. Brian Needelman Univ. of Illinois Dept. of Natural Resources and Environmental Sciences. Champaign, IL needelma@uiuc.edu -------------------------------------- Date: Thu, 04 Jan 1996 14:33:25 -0500 From: Cynthia Grant <cgrant@EM.AGR.CA> To: xichang@unixg.ubc.ca Subject: Refs. on soil health reqest -Reply Hello Scott I believe that the Centre for Land and Biological Resource Research, Agriculture and Agri-Food Canada in Ottawa just come out with a publication on the Health of Soils. You might want to contact Chung Wang. I think their phone number is 613-995-5011. (should be 613- 759-1000) Also, John Doran of Lethbridge Research Station has been working in this area and has done some review papers on the topic. The phone number there is: 403-327-4561. Good Luck Cynthia Grant
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