[ { "key": "99B7U7DN", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/99B7U7DN", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/99B7U7DN", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/12059/items/T7QHNMI8", "type": "application/json" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "99B7U7DN", "version": 1, "parentItem": "T7QHNMI8", "itemType": "note", "note": "

the distance that sheep travel from water may be affected by salt contents of fodder - with higher salt contents a higher water dependence is to be expected. pg 804

", "tags": [], "relations": {}, "dateAdded": "2010-04-20T08:18:52Z", "dateModified": "2010-04-20T08:18:52Z" } }, { "key": "Q6TE4JF6", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/Q6TE4JF6", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/Q6TE4JF6", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/12059/items/T7QHNMI8", "type": "application/json" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "Q6TE4JF6", "version": 1, "parentItem": "T7QHNMI8", "itemType": "note", "note": "

Shep distribution in padock influenced by wind direction pg 804

", "tags": [], "relations": {}, "dateAdded": "2010-04-20T08:18:52Z", "dateModified": "2010-04-20T08:18:52Z" } }, { "key": "UHETQXD2", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/UHETQXD2", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/UHETQXD2", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/12059/items/T7QHNMI8", "type": "application/json" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "UHETQXD2", "version": 1, "parentItem": "T7QHNMI8", "itemType": "note", "note": "

heavy utilization in the vicinity of shade is confined to relatively small areas suggesting trampling may be more important than grazing. pg 804

", "tags": [], "relations": {}, "dateAdded": "2010-04-20T08:18:52Z", "dateModified": "2010-04-20T08:18:52Z" } }, { "key": "C3ZF56TV", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/C3ZF56TV", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/C3ZF56TV", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/12059/items/6E4PX9DJ", "type": "application/json" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } } }, "data": { "key": "C3ZF56TV", "version": 1, "parentItem": "6E4PX9DJ", "itemType": "attachment", "linkMode": "linked_url", "title": "991f1b0a2ecf613688d2a29eb1cd1ba1", "accessDate": "2010-04-08T12:33:58Z", "url": "http://www.sciencedirect.com/science/article/B6WH9-45RFHW7-25/2/991f1b0a2ecf613688d2a29eb1cd1ba1", "note": "", "contentType": "", "charset": "", "tags": [], "relations": {}, "dateAdded": "2010-04-20T08:18:52Z", "dateModified": "2010-04-20T08:18:52Z" } }, { "key": "T7QHNMI8", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/T7QHNMI8", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/T7QHNMI8", "type": "text/html" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "creatorSummary": "Orr", "parsedDate": "1980", "numChildren": 3 }, "data": { "key": "T7QHNMI8", "version": 1, "itemType": "journalArticle", "title": "Effects of sheep grazing Astrebla grassland in central western Queensland. 1. Effects of grazing pressure and livestock distribution", "creators": [ { "creatorType": "author", "firstName": "D M", "lastName": "Orr" } ], "abstractNote": "The effects of grazing pressure on plant responses and livestock distribution in Astrebla grassland were determined from paddocks subject to commercial grazing by sheep at light, medium or heavy grazing pressure. Increased grazing pressure reduced the projected foliage cover of Astrebla spp., the basal area of which was similar under light and medium grazing pressure, and was reduced under heavy grazing pressure. Differences in the density and size of Astrebla spp. tussocks were apparent under the three grazing pressures. Other perennial grasses, notably Aristidu latifolia and A. leptopoda, were most frequent under light grazing pressure. Numerical classification of the sampling sites, which were arranged on a regular grid, allowed the grazing pattern to be established. Heavy utilization was shown to be associated with wind direction, shade availability and watering facilities.", "publicationTitle": "Australian Journal of Agricultural Research", "publisher": "", "place": "", "date": "1980", "volume": "31", "issue": "4", "section": "", "partNumber": "", "partTitle": "", "pages": "797-806", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "Aust. J. Agr. Res.", "DOI": "10.1071/AR9800797", "citationKey": "", "url": "", "accessDate": "", "PMID": "", "PMCID": "", "ISSN": "", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "EN", "libraryCatalog": "", "callNumber": "", "rights": "", "extra": "", "tags": [ { "tag": "grazing pressure" }, { "tag": "rangeland" }, { "tag": "water point" } ], "collections": [ "7QUWEHDB" ], "relations": {}, "dateAdded": "2010-04-20T08:18:52Z", "dateModified": "2010-04-20T08:18:52Z" } }, { "key": "43TKDMNA", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/43TKDMNA", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/43TKDMNA", "type": "text/html" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "creatorSummary": "Orr", "parsedDate": "1980", "numChildren": 0 }, "data": { "key": "43TKDMNA", "version": 1, "itemType": "journalArticle", "title": "Effect of sheep grazing Astrebla grassland in central western Queensland. 2. Effects of seasonal rainfall", "creators": [ { "creatorType": "author", "firstName": "D M", "lastName": "Orr" } ], "abstractNote": "The response of Astrebla grassland pasture to summer rainfall was measured at sites in commercially grazed paddocks which were subject to different grazing pressures. The interrelationship between forage use and plant variates was examined by regression analysis. Above-average rainfall resulted in increases in basal area and projected foliage cover of Astrebla spp. under grazing pressures equivalent to 50% forage use of A. lappacea. Increased forage use in the dry period before this rainfall reduced the basal area and projected foliage cover of Astrebla and resulted in lower yields of Astrebla following the rainfall. These lower yields of Astrebla were associated with higher yields of annual grasses and forbs than where forage use had been light. Astrebla yields were highest under light forage use. The frequency of two undesirable species, Amaranthus niitchellii and Tribulus terrestris, was highest under heavy forage use, and was associated with a decline in the number of other annual grass and forb species.", "publicationTitle": "Australian Journal of Agricultural Research", "publisher": "", "place": "", "date": "1980", "volume": "31", "issue": "4", "section": "", "partNumber": "", "partTitle": "", "pages": "807-820", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "Aust. J. Agr. Res.", "DOI": "10.1071/AR9800807", "citationKey": "", "url": "", "accessDate": "", "PMID": "", "PMCID": "", "ISSN": "", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "EN", "libraryCatalog": "", "callNumber": "", "rights": "", "extra": "", "tags": [ { "tag": "grazing pressure" }, { "tag": "rangeland" }, { "tag": "water point" } ], "collections": [ "7QUWEHDB" ], "relations": {}, "dateAdded": "2010-04-20T08:18:52Z", "dateModified": "2010-04-20T08:18:52Z" } }, { "key": "6E4PX9DJ", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/6E4PX9DJ", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/6E4PX9DJ", "type": "text/html" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "creatorSummary": "du Plessis", "parsedDate": "2001", "numChildren": 1 }, "data": { "key": "6E4PX9DJ", "version": 1, "itemType": "journalArticle", "title": "Effective rainfall defined using measurements of grass growth in the Etosha National Park, Namibia", "creators": [ { "creatorType": "author", "firstName": "W. P.", "lastName": "du Plessis" } ], "abstractNote": "The most important environmental factors controlling successful plant germination and subsequent establishment in arid climates are rainfall amount, spatial and temporal rainfall distribution and soil moisture availability. In general, drier areas have a greater variability in rainfall. Agriculturists and ecologists commonly perceive total annual rainfall as a reliable indicator of vegetation growth and production during the rainy season. However, because of the intrinsic high spatial and temporal variability of annual rainfall in drier areas, it is in fact a poor indicator of actual vegetation growth.This paper aims at presenting simple methods modeling effective use of rain by grass for germination and establishment (effective rainfall) in the Etosha National Park (Etosha). These methods, which aim at providing a simple predictive tool for grass growth and production, are based on measurements of grass growth in relation to 10-day interval rainfall and daily measurements of rainfall. Studying the influence of soil moisture and other factors on grass growth is outside of the scope of this study. Effective rainfall calculated using daily measurements of rainfall from the rainy season of 1994/1995 indicate that between 35·5 to 57·6% of total annual rainfall is effective rainfall for Etosha.", "publicationTitle": "Journal of Arid Environments", "publisher": "", "place": "", "date": "2001", "volume": "48", "issue": "3", "section": "", "partNumber": "", "partTitle": "", "pages": "397-417", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "", "DOI": "10.1006/jare.2000.0752", "citationKey": "", "url": "http://www.sciencedirect.com/science/article/B6WH9-45RFHW7-25/2/991f1b0a2ecf613688d2a29eb1cd1ba1", "accessDate": "", "PMID": "", "PMCID": "", "ISSN": "0140-1963", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "", "libraryCatalog": "", "callNumber": "", "rights": "", "extra": "", "tags": [ { "tag": "Etosha" }, { "tag": "effective rainfall" }, { "tag": "grass production" }, { "tag": "modeling" }, { "tag": "rainfall" }, { "tag": "water point" } ], "collections": [ "7QUWEHDB" ], "relations": {}, "dateAdded": "2010-04-20T08:18:52Z", "dateModified": "2010-04-20T08:18:52Z" } }, { "key": "8FXVG88R", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/8FXVG88R", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/8FXVG88R", "type": "text/html" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "creatorSummary": "Andrew and Lange", "parsedDate": "1986", "numChildren": 0 }, "data": { "key": "8FXVG88R", "version": 1, "itemType": "journalArticle", "title": "Development of a new piosphere in arid chenopod shrubland grazed by sheep. 2. Changes to the vegetation", "creators": [ { "creatorType": "author", "firstName": "M H", "lastName": "Andrew" }, { "creatorType": "author", "firstName": "R T", "lastName": "Lange" } ], "abstractNote": "The initial development of a piosphere created by stocking a new watering trough with ca. 200 sheep at a near-pristine site in arid chenopod shrubland near Whyalla, South Australia, was studied. The following variables were monitored for up to 8 years using fenced plots as controls:shrub mortality; forage biomass and defoliation of the dominant shrubs and short-lived grasses; linear dimensions of Rhagodia ulicina; the density of short-lived species; and the invasion of exotics. Patterns in these variables were looked for which reflected the attenuation of stocking pressure with distance from water; that is, 'piosphere patterns'.\n\nPiosphere patterns were detected for many variables. Those with values increasing towards the trough were mortality of the main forage shrub Atriplex vesicaria. the density of three short-lived taxa, viz. the bassias (Sclerolaena obliquicuspis, S. patenticuspis. Maireana sclerolaenoides), Tetragonia tetragonoides, and annual Zygophyllum spp. (Z. crenatum. Z. ovatum), and growth of short-lived grass species when sheep stocking pressure was low. Variables with values decreasing towards the trough were grass biomass, percentage of A. vesicaria individuals in flower, the percentage foliation of A. vesicaria and of the forage shrub Maireana sedifolia, and shrub forage biomass of A. vesicaria and M. sedifolia.\n\nThe rate at which these patterns were registered varied. After only 3 months, a piosphere pattern was evident for grass biomass. Marrubium vulgare, an introduced weed, invaded the trough site within the first 6 months. Almost no A. vesicaria shrubs had died after 2 years, but after 8 years there was a marked piosphere pattern in their mortality. The piosphere patterns in forage biomass and defoliation of A. vesicaria and M. sedifolia became more pronounced with time.\n\nSome variables did not exhibit a piosphere pattern, such as the dimensions of the shrub R. ulicina and the densities of successive cohorts of the forb Erodium spp., even though there was an overall effect of grazing in reducing their values. There was no mortality of two dominant shrubs, M. sedifolia and R. ulicina, during the first 8 years.", "publicationTitle": "Austral Ecology", "publisher": "", "place": "", "date": "1986", "volume": "11", "issue": "4", "section": "", "partNumber": "", "partTitle": "", "pages": "411-424", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "Austral Ecol.", "DOI": "10.1111/j.1442-9993.1986.tb01410.x", "citationKey": "", "url": "", "accessDate": "", "PMID": "", "PMCID": "", "ISSN": "", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "EN", "libraryCatalog": "", "callNumber": "0000", "rights": "", "extra": "", "tags": [ { "tag": "Australia" }, { "tag": "piosphere" }, { "tag": "rangeland" }, { "tag": "water point" } ], "collections": [ "7QUWEHDB" ], "relations": {}, "dateAdded": "2010-04-20T08:18:52Z", "dateModified": "2010-04-20T08:18:52Z" } }, { "key": "8SVIKWHB", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/8SVIKWHB", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/8SVIKWHB", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/12059/items/G5GZ8VAV", "type": "application/json" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "8SVIKWHB", "version": 1, "parentItem": "G5GZ8VAV", "itemType": "note", "note": "

Track Density TD pg 34

\n

ln(TD)=a + bD + cS + dA + eN

\n

with

\n

D = distance in km

\n

S = Salinity (%) of water

\n

A = Age of water point

\n

N = Number of animals

", "tags": [], "relations": {}, "dateAdded": "2010-04-07T13:50:35Z", "dateModified": "2010-04-07T13:50:35Z" } }, { "key": "P9TQWZD8", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/P9TQWZD8", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/P9TQWZD8", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/12059/items/G5GZ8VAV", "type": "application/json" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "P9TQWZD8", "version": 1, "parentItem": "G5GZ8VAV", "itemType": "note", "note": "

The use of track density should be evaluated. there seem to be some issues.

", "tags": [], "relations": {}, "dateAdded": "2010-04-07T13:50:35Z", "dateModified": "2010-04-07T13:50:35Z" } }, { "key": "2Z6ISJ22", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/2Z6ISJ22", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/2Z6ISJ22", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/12059/items/G5GZ8VAV", "type": "application/json" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "2Z6ISJ22", "version": 1, "parentItem": "G5GZ8VAV", "itemType": "note", "note": "

The physiological dependence of livestock
on water results in activity being concentrated in
the vicinity of long-lasting water, and dissipating
rapidly with increasing distance from it pg31

", "tags": [], "relations": {}, "dateAdded": "2010-04-07T13:50:35Z", "dateModified": "2010-04-07T13:50:35Z" } }, { "key": "9K7MN744", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/9K7MN744", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/9K7MN744", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/12059/items/G5GZ8VAV", "type": "application/json" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "9K7MN744", "version": 1, "parentItem": "G5GZ8VAV", "itemType": "note", "note": "

The heavily impacted areas that surround water
sources provide opportunities for exotic weed
species to establish and then spread pg32

", "tags": [], "relations": {}, "dateAdded": "2010-04-07T13:50:35Z", "dateModified": "2010-04-07T13:50:35Z" } }, { "key": "HREDVPP2", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/HREDVPP2", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/HREDVPP2", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/12059/items/G5GZ8VAV", "type": "application/json" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "HREDVPP2", "version": 1, "parentItem": "G5GZ8VAV", "itemType": "note", "note": "

The construction of tracks and roads can also have
profound, broad-scale impacts on landscape function
in rangelands, creating new drainage lines and consequently
desiccating landscapes deprived of run-on. pg35

", "tags": [], "relations": {}, "dateAdded": "2010-04-07T13:50:35Z", "dateModified": "2010-04-07T13:50:35Z" } }, { "key": "DUNAGS2P", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/DUNAGS2P", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/DUNAGS2P", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/12059/items/G5GZ8VAV", "type": "application/json" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "DUNAGS2P", "version": 1, "parentItem": "G5GZ8VAV", "itemType": "note", "note": "

Relative grazing activity is calculated as pg 32:

\n

RGA = e(CxD) x P

\n

with

\n

C= -0.392 x S

\n

D = distance from water

\n

S = salinity of water

\n

P = differences in preferences for different vegetation types.

", "tags": [], "relations": {}, "dateAdded": "2010-04-07T13:50:35Z", "dateModified": "2010-04-07T13:50:35Z" } }, { "key": "KTUNQ96V", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/KTUNQ96V", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/KTUNQ96V", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/12059/items/G5GZ8VAV", "type": "application/json" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "KTUNQ96V", "version": 1, "parentItem": "G5GZ8VAV", "itemType": "note", "note": "

Rabbits are not dependent on surface water for survival and, hence, areas might be devoid of watering points but still
severely impacted by rabbits pg 35

", "tags": [], "relations": {}, "dateAdded": "2010-04-07T13:50:35Z", "dateModified": "2010-04-07T13:50:35Z" } }, { "key": "RPFKF7FG", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/RPFKF7FG", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/RPFKF7FG", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/12059/items/G5GZ8VAV", "type": "application/json" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "RPFKF7FG", "version": 1, "parentItem": "G5GZ8VAV", "itemType": "note", "note": "

Areas remote from water sources can provide
benchmark sites indicative of maximum biological
integrity. pg 31

", "tags": [], "relations": {}, "dateAdded": "2010-04-07T13:50:35Z", "dateModified": "2010-04-07T13:50:35Z" } }, { "key": "VG4RQJK9", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/VG4RQJK9", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/VG4RQJK9", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/12059/items/G5GZ8VAV", "type": "application/json" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "VG4RQJK9", "version": 1, "parentItem": "G5GZ8VAV", "itemType": "note", "note": "

# R code to generate graph

\n

# rga = relative grazing activity
rga = function (D, S, P)  {
C = -0.392 * S
exp(C*D)*P
}

curve(rga (x, 0.5, 0.5), from=0, to=5, xlab=\"Distance (km)\", ylab=\"RGA\")

", "tags": [], "relations": {}, "dateAdded": "2010-04-07T13:50:35Z", "dateModified": "2010-04-07T13:50:35Z" } }, { "key": "G5GZ8VAV", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/G5GZ8VAV", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/G5GZ8VAV", "type": "text/html" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "creatorSummary": "Pringle and Landsberg", "parsedDate": "2004", "numChildren": 9 }, "data": { "key": "G5GZ8VAV", "version": 1, "itemType": "journalArticle", "title": "Predicting the distribution of livestock grazing pressure in rangelands", "creators": [ { "creatorType": "author", "firstName": "H.J.R.", "lastName": "Pringle" }, { "creatorType": "author", "firstName": "J.", "lastName": "Landsberg" } ], "abstractNote": "Because grazing by livestock is one of the primary threats to rangeland biodiversity, but is unevenly distributed in space, rangeland monitoring programmes need to take account of the distribution of grazing pressure in order to distinguish between grazing-induced change, seasonal fluctuations and changes that are a result of other threats. Livestock watering places are one of the major influences that give spatial expression to gradations in grazing activity. Using research results from the goldfields of Western Australia, we show how distance from water can be incorporated in spatial models to predict cumulative grazing pressure at different sites within paddocks. Two surrogates of grazing activity are illustrated: one relying on a commercially available model, and one developed from measures of track density. Factors other than distance from water can also have profound effects on the distribution of grazing pressure and its impacts at landscape and regional scales, and we review some of these briefly. Finally, we outline key spatial implications for the design of rangeland monitoring programmes.", "publicationTitle": "Austral Ecology", "publisher": "", "place": "", "date": "2004", "volume": "29", "issue": "1", "section": "", "partNumber": "", "partTitle": "", "pages": "31-39", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "Austral Ecol.", "DOI": "10.1111/j.1442-9993.2004.01363.x", "citationKey": "", "url": "", "accessDate": "", "PMID": "", "PMCID": "", "ISSN": "", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "EN", "libraryCatalog": "", "callNumber": "", "rights": "", "extra": "", "tags": [ { "tag": "Water remoteness" }, { "tag": "arid zone" }, { "tag": "grazing pressure" }, { "tag": "modeling" }, { "tag": "rabbit" }, { "tag": "water point" } ], "collections": [ "7QUWEHDB" ], "relations": {}, "dateAdded": "2010-04-07T13:50:35Z", "dateModified": "2010-04-07T13:50:35Z" } }, { "key": "I26RJSZ7", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/I26RJSZ7", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/I26RJSZ7", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/12059/items/U5KZG2T8", "type": "application/json" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } } }, "data": { "key": "I26RJSZ7", "version": 1, "parentItem": "U5KZG2T8", "itemType": "attachment", "linkMode": "linked_url", "title": "cd301f61c36c8ca320e590038a90e749", "accessDate": "2009-10-26T02:11:44Z", "url": "http://www.sciencedirect.com/science/article/B6V5X-4SG01HS-5/2/cd301f61c36c8ca320e590038a90e749", "note": "", "contentType": "", "charset": "", "tags": [], "relations": {}, "dateAdded": "2010-03-29T14:49:35Z", "dateModified": "2010-03-29T14:49:35Z" } }, { "key": "E6V5QZTC", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/E6V5QZTC", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/E6V5QZTC", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/12059/items/U5KZG2T8", "type": "application/json" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "E6V5QZTC", "version": 1, "parentItem": "U5KZG2T8", "itemType": "note", "note": "

The importance of water-remoteness as a mediator of grazing pressure in Australian arid lands p.1449

", "tags": [], "relations": {}, "dateAdded": "2010-03-29T14:49:35Z", "dateModified": "2010-03-29T14:49:35Z" } }, { "key": "M7PBXMN5", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/M7PBXMN5", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/M7PBXMN5", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/12059/items/U5KZG2T8", "type": "application/json" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "M7PBXMN5", "version": 1, "parentItem": "U5KZG2T8", "itemType": "note", "note": "

It is assumed that areas beyond these distances will generally receive some respite from grazing pressure during the growing season and allow the completion of flowering, seeding and other recovery for plants. p1450

", "tags": [], "relations": {}, "dateAdded": "2010-03-29T14:49:35Z", "dateModified": "2010-03-29T14:49:35Z" } }, { "key": "P6TBC55G", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/P6TBC55G", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/P6TBC55G", "type": "text/html" }, "up": { "href": "https://api.zotero.org/groups/12059/items/U5KZG2T8", "type": "application/json" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "numChildren": 0 }, "data": { "key": "P6TBC55G", "version": 1, "parentItem": "U5KZG2T8", "itemType": "note", "note": "

Because of the necessary buffer distances around existing water points it is more effective to design a network of few large reserves rather than many small ones. This will be much more efficient in terms of the number of water points requiring closure, but also if appropriately designed will achieve water-remoteness at distances well beyond the threshold distances proposed in this study. Some biodiversity benefits may only accrue at these greater distances. p. 1457

", "tags": [], "relations": {}, "dateAdded": "2010-03-29T14:49:35Z", "dateModified": "2010-03-29T14:49:35Z" } }, { "key": "R39ART22", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/R39ART22", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/R39ART22", "type": "text/html" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "creatorSummary": "Mapaure and Ekandjo", "numChildren": 0 }, "data": { "key": "R39ART22", "version": 1, "itemType": "journalArticle", "title": "The impact of large herbivores on vegetation around water points in Gondwana Canyon Park, southern Namibia", "creators": [ { "creatorType": "author", "firstName": "I", "lastName": "Mapaure" }, { "creatorType": "author", "firstName": "L K", "lastName": "Ekandjo" } ], "abstractNote": "", "publicationTitle": "", "publisher": "", "place": "", "date": "in prep", "volume": "", "issue": "", "section": "", "partNumber": "", "partTitle": "", "pages": "", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "", "DOI": "", "citationKey": "", "url": "", "accessDate": "", "PMID": "", "PMCID": "", "ISSN": "", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "", "libraryCatalog": "", "callNumber": "", "rights": "", "extra": "", "tags": [], "collections": [ "7QUWEHDB" ], "relations": {}, "dateAdded": "2010-03-29T14:49:35Z", "dateModified": "2010-03-29T14:49:35Z" } }, { "key": "IU457I4F", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/IU457I4F", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/IU457I4F", "type": "text/html" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "creatorSummary": "Klintenberg and Verlinden", "parsedDate": "2007", "numChildren": 0 }, "data": { "key": "IU457I4F", "version": 1, "itemType": "journalArticle", "title": "Water points and their influence on grazing resources in central Northern Namibia", "creators": [ { "creatorType": "author", "firstName": "P.", "lastName": "Klintenberg" }, { "creatorType": "author", "firstName": "A.", "lastName": "Verlinden" } ], "abstractNote": "Debate among scientists about ecological dynamics and appropriate management of semi-arid rangelands has led to a challenge of received wisdoms of range management and pastoral development in dryland Africa. In our study, we investigated impacts of grazing on grass composition around permanent water points along a pipeline and around a traditional hand-dug well in an important grazing area in central northern Namibia. Grass species abundance and selected environmental variables sampled along transects radiating out from these water points were analysed using Canonical Correspondence Analysis (CCA). Significant grazing-induced changes, manifested by palatable perennial grasses being replaced by less palatable annual grasses, were identified around water points along the pipeline. There annual grasses Schmidtia kalihariensis and Aristida stipioides dominate the vegetation as far as 5 km from the water points. No significant grazing-induced changes in grass composition were observed around the hand-dug well. Private ownership leading to stronger control of access to traditional wells compared to the open access water points along the pipeline seems to be a key factor preventing overutilisation of grazing resources around the former.", "publicationTitle": "Land degradation and development", "publisher": "", "place": "", "date": "2007", "volume": "19", "issue": "1", "section": "", "partNumber": "", "partTitle": "", "pages": "1-20", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "", "DOI": "10.1002/ldr.809", "citationKey": "", "url": "", "accessDate": "", "PMID": "", "PMCID": "", "ISSN": "", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "EN", "libraryCatalog": "", "callNumber": "", "rights": "", "extra": "", "tags": [], "collections": [ "7QUWEHDB" ], "relations": {}, "dateAdded": "2010-03-29T14:49:35Z", "dateModified": "2010-03-29T14:49:35Z" } }, { "key": "UUBWSZPU", "version": 1, "library": { "type": "group", "id": 12059, "name": "Savanna Ecology", "links": { "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology", "type": "text/html" } } }, "links": { "self": { "href": "https://api.zotero.org/groups/12059/items/UUBWSZPU", "type": "application/json" }, "alternate": { "href": "https://www.zotero.org/groups/savanna_ecology/items/UUBWSZPU", "type": "text/html" } }, "meta": { "createdByUser": { "id": 18534, "username": "pgraz", "name": "Patrick Graz", "links": { "alternate": { "href": "https://www.zotero.org/pgraz", "type": "text/html" } } }, "creatorSummary": "Katjitua and Ward", "numChildren": 0 }, "data": { "key": "UUBWSZPU", "version": 1, "itemType": "journalArticle", "title": "Soil and vegetation changes under livestock production in the northern Kalahari, Namibia", "creators": [ { "creatorType": "author", "firstName": "Mutjinde", "lastName": "Katjitua" }, { "creatorType": "author", "firstName": "D.", "lastName": "Ward" } ], "abstractNote": "The spatial scale and intensity of rangeland degradation around water points in arid and semi-arid environments depend on the population density of livestock, the duration of water point use and the distance livestock travel from water points. We visually established a broadscale pattern of vegetation zonation along a grazing gradient on 28 settlements in the Kalahari to place five sampling points from artificial water points. We selected four settlements for a more intense study of vegetation and soil changes under livestock production. We tested the effect of livestock on species diversity of herbaceous and woody plants, structural parameters of woody plants, and soil moisture and nutrient contents. We found that the effect of livestock on vegetation was confined to the vicinity of the artificial water points. The diversity of herbaceous and woody species decreased under high livestock pressure, but the abundance of herbaceous species present near water points increased significantly. Soil parameters were not influenced significantly by livestock activities along the grazing gradient, however the upper soil layer had significantly higher organic carbon and total nitrogen, but lower soil moisture content. It appeared that livestock impact around artificial water points in the Kalahari was confined to the immediate areas of the water points. In contrast, livestock impact may also have resulted in a relatively uniform vegetation and soil changes beyond the 200 m distance from the water points.", "publicationTitle": "Dinteria", "publisher": "", "place": "", "date": "submitted", "volume": "", "issue": "", "section": "", "partNumber": "", "partTitle": "", "pages": "", "series": "", "seriesTitle": "", "seriesText": "", "journalAbbreviation": "", "DOI": "", "citationKey": "", "url": "", "accessDate": "", "PMID": "", "PMCID": "", "ISSN": "", "archive": "", "archiveLocation": "", "shortTitle": "", "language": "", "libraryCatalog": "", "callNumber": "", "rights": "", "extra": "", "tags": [], "collections": [ "7QUWEHDB" ], "relations": {}, "dateAdded": "2010-03-29T14:49:35Z", "dateModified": "2010-03-29T14:49:35Z" } } ]