Opinions of Savory's methods differ greatly between ranchers/farmers and dryland ecologists.
Among other controversies, Savory claims that intensive trampling and foraging will, among other things, break up biological soil crusts. This is true, but biological crusts are ecologically important parts of dryland communities. But... " Soils in arid and semiarid grasslands often have significant areas covered by biological crusts [ 53 – 55 ]. These are made up of bacteria, cyanobacteria, algae, mosses, and lichens and are essential to the health of these grasslands. Biological crusts stabilize soils, increase soil organic matter and nutrient content, absorb dew during dry periods, and fix nitrogen [ 53 , 56 – 60 ]. Crusts enhance soil stability and reduce water runoff by producing more microcatchments on soil surfaces. They increase water absorbing organic matter, improve nutrient flow, germination and establishment of some plants, while dark crusts may stimulate plant growth by producing warmer soil temperatures and water uptake in cold deserts [ 61 ]. Some crusts are hydrophobic, shedding water [ 60 ]. Biological soil crusts are fragile, highly susceptible to trampling [ 61 – 63 ], and are slow to recover from trampling impacts [ 64 ]. Loss of these crusts results in increased erosion and reduced soil fertility. The loss of crusts in the bunchgrass communities of the western USA may be largely responsible for the widespread establishment of cheatgrass and other exotic annuals [ 23 , 58 , 65 ]. The rapid spread of introduced weeds throughout the arid western USA is estimated at over 2000 hectares per day [ 66 ], largely due to livestock disturbance." Carter, J., Jones, A., O’Brien, M., Ratner, J., & Wuerthner, G. (2014). Holistic management: misinformation on the science of grazed ecosystems. International Journal of Biodiversity , 2014 , 1-10. You can read more about biological soil crusts here. Antoninka, A., Faist, A., Rodriguez‐Caballero, E., Young, K. E., Chaudhary, V. B., Condon, L. A., & Pyke, D. A. (2020). Biological soil crusts in ecological restoration: Emerging research and perspectives. Restoration Ecology , 28 , S3-S8. I'm an ecologist not a rancher (nor a GMO or nuclear power advocate), so my sympathies lie with the biological crusts and indigenous plant species that get crowded out, rather than with the ranchers. But a perusal of google scholar will give you a sense of the range of opinion among practitioners and academics in both camps. Karen Saunders -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#7312): https://groups.io/g/marxmail/message/7312 Mute This Topic: https://groups.io/mt/81380658/21656 -=-=- POSTING RULES & NOTES #1 YOU MUST clip all extraneous text when replying to a message. #2 This mail-list, like most, is publicly & permanently archived. #3 Subscribe and post under an alias if #2 is a concern. -=-=- Group Owner: [email protected] Unsubscribe: https://groups.io/g/marxmail/leave/8674936/21656/1316126222/xyzzy [[email protected]] -=-=-=-=-=-=-=-=-=-=-=-
