Rangeland Ecology & Management最新文献

{"title":"Mapping Floral Resources in Montane Landscapes Using Unmanned Aerial Systems and Two-step Random Forest Classifications","authors":"Jesse Tabor ,&nbsp;Alexander Hernandez ,&nbsp;Diana Cox-Foster ,&nbsp;Byron G. Love ,&nbsp;Lindsie M. McCabe ,&nbsp;Matthew Robbins ,&nbsp;Jonathan B.U. Koch","doi":"10.1016/j.rama.2024.06.016","DOIUrl":"10.1016/j.rama.2024.06.016","url":null,"abstract":"<div><div>Monitoring floral biodiversity is a critical step in understanding terrestrial ecosystems. However, manual methods to quantify flowering vegetation are costly in time and personnel. In large landscapes, these limited methods may not capture the spatial and temporal variation of floral resources. Recent advances in sensors and unmanned aerial vehicle (UAV) platforms offer opportunities to characterize the dynamic distribution of floral resources at the landscape level. In this study, UAV imagery and a multistep machine learning classification analysis were used to quantify floral resources in nonagricultural environments, where topography, vegetation, and inflorescence size were variable. Seven flowering species covering an area of 2 138 m² were classified throughout our study, equaling 0.5% of the overall landscape. We determined the period of flowering for important species based on the temporal changes of the floral area classified from UAV images. Models performed well considering the extreme rarity of flowers in the UAV images. The flower class in the land cover classification models performed well with an average sensitivity of 0.77 and average specificity of 0.99. Individual flower classes also performed well with the majority of flower classes receiving sensitivity and specificity values of over 0.90. The use of UAVs is a feasible method for characterizing floral resources in nonagricultural settings. Classifications would benefit from a more robust and comprehensive UAV and floral resource sampling plan, to better characterize the variability of floral resources in UAV imagery.</div></div>","PeriodicalId":49634,"journal":{"name":"Rangeland Ecology & Management","volume":"98 ","pages":"Pages 223-236"},"PeriodicalIF":2.4,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142746828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diversity and Abundance of Arbuscular Mycorrhizal Fungi and Soil Bacteria in Purshia tridentata Stands in the Sagebrush Steppe","authors":"David Eduardo Prado-Tarango ,&nbsp;Ricardo Mata-González ,&nbsp;Dana Sanchez ,&nbsp;Lisa Ellsworth","doi":"10.1016/j.rama.2024.06.013","DOIUrl":"10.1016/j.rama.2024.06.013","url":null,"abstract":"<div><div>Soil microorganisms, including arbuscular mycorrhizal fungi (AMF) and nitrogen fixing bacteria, require better integration into ecological restoration programs as they might facilitate plant establishment. Both are believed to be critical for the establishment of native rangeland plant species such as <em>Purshia tridentata</em>. We evaluated the AMF and bacterial diversity and abundance from soils in 1) areas with undisturbed P. tridentata stands in rangelands of north-central Oregon and 2) areas where <em>P. tridentata</em> was eliminated because of wildfires. We collected soil from three locations 1) areas with undisturbed <em>P. tridentata</em> stands in rangelands of North-central Oregon and 2) areas where <em>P. tridentata</em> was eliminated because of wildfires. We also collected roots from live <em>P tridentata</em> plants<em>.</em> We used 16s rRNA gene and ITS amplicon sequencing to determine and compare bacterial and AMF microbiomes. We wanted to evaluate the soil bacteria to the family level to determine the presence of the Frankiaceae family, and the AMF to the species level to evaluate which AMF species colonized this plant. Bacterial and AMF diversity did not vary between locations, but diversity and abundance of both parameters differed in roots (<em>P</em> &lt; 0.05) from those of soils. AMF abundance in roots was dominated by <em>Claroideoglomus</em> and <em>Glomus</em>. The major bacterial familiy detected in soil samples was Chthoniobacteraceae, while Frankiaceae was present to a very low extent. Our results suggest that current microbial communities in the study area are homogeneous instead of being affected by the elimination of <em>P. tridentata</em>. However, our data reveals the current mycorrhizal communities associated with <em>P. tridentata</em> which can be used for restoration purposes.</div></div>","PeriodicalId":49634,"journal":{"name":"Rangeland Ecology & Management","volume":"98 ","pages":"Pages 18-27"},"PeriodicalIF":2.4,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142746897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Late Summer Intensive Grazing, an Alternative to Herbicide Application in Rangelands of the Flooding Pampa","authors":"Joaquín Asad ,&nbsp;Kevin Van Sundert ,&nbsp;Ana V. Eljall Qüesta ,&nbsp;Pablo Preliasco ,&nbsp;Josefina L. De Paepe","doi":"10.1016/j.rama.2024.06.010","DOIUrl":"10.1016/j.rama.2024.06.010","url":null,"abstract":"<div><div>The Flooding Pampa harbors grasslands of high conservation value and provides grazing ground for extensive livestock production in uplands while lowlands are less productive. The Aboveground Net Primary Productivity (ANPP) of cool-season C3 grasses limits livestock production in this region. Consequently, two managements have been implemented to promote ANPP of these upland grasses, in contrast to the No Promotion (NP) traditional management with continuous stocking during the entire year: Herbicide Promotion (HP), and less commonly, Late Summer Intensive Grazing (LSIG). Here, we compare the effectiveness of LSIG as a potential alternative to herbicide application in promoting cool-season grass production and evaluate both short- and longer-term impacts on inter- and sub-annual ANPP. To this end, we integrated remotely sensed ANPP data from 2013 to 2019 with rainfall data from meteorological stations, field observations, and management information provided by farm managers. We found that in comparison to NP in uplands, both HP and LSIG successfully promoted ANPP during the cooler months (<em>P</em> &lt; 0.05). However, under HP, this came at the expense of warm-season grasses and annual ANPP, to such an extent that upland annual ANPP under HP was reduced to similar values of the normally less productive lowlands. Our study showed that cool-season grasses can be successfully promoted with or without herbicide use, but HP leads to a longer-term degradation of forage resources. Contrary to HP, LSIG is a management that reconciles the dual goals of livestock production and grassland conservation in the Flooding Pampa.</div></div>","PeriodicalId":49634,"journal":{"name":"Rangeland Ecology & Management","volume":"98 ","pages":"Pages 9-17"},"PeriodicalIF":2.4,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142746896","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Soil Carbon and Nitrogen Responses to Long-Term Flood Irrigation and Fertilization in High-Elevation Hay Meadows","authors":"Daniel M. Adamson ,&nbsp;Urszula Norton ,&nbsp;Jay B. Norton ,&nbsp;Shannon E. Albeke ,&nbsp;Brian M. Sebade ,&nbsp;Linda T.A. van Diepen","doi":"10.1016/j.rama.2024.07.002","DOIUrl":"10.1016/j.rama.2024.07.002","url":null,"abstract":"<div><div>Rangelands are an important grazing resource worldwide, but in many regions, supplemental forage is needed to support grazing during parts of the year. Mountain irrigated hay meadows are an integral hay-producing component of livestock operations in the Intermountain Western United States (US), but productive capacity is made challenging by short growing season (elevation &gt;2000 m) and inefficient flood irrigation strategies. Further, these factors have reduced residue decomposition and led to the development of an organic horizon at the soil surface which stores large amounts of soil organic matter (SOM) and nitrogen (N). Better understanding of N-cycling and SOM dynamics is necessary to improve N management and sustainability of forage production in meadows. A field study was conducted at four ranches in southern Wyoming and northern Colorado, US, in 2021 to evaluate the effect of long-term flood irrigation and N fertilization on soil carbon (C) and N pools. Soil pits were excavated to 1.5-m depth in three management systems: unirrigated rangeland, irrigated-unfertilized meadow, and irrigated-fertilized meadow. In each pit, genetic soil horizons were sampled and analyzed for total organic C (TOC), total N (TN), dissolved organic C (DOC), and N (DON), microbial biomass C (MBC), and N (MBN), potentially mineralizable C (PMC), and N (PMN), nitrate, and ammonium. Irrigation dramatically increased TOC concentration at the soil surface, and also increased TOC in the entire profile. However, N fertilization negated the effects of irrigation, as fertilized meadow stabile and labile C and N pools more closely resembled those of rangelands. Fertilized and unfertilized meadows had less labile C and N per unit of stable C and N compared to rangelands, and lower PMN, suggesting lower SOM mineralization or loss to leaching. Alternative irrigation strategies that reduce soil waterlogging will likely improve SOM cycling and forage production in hay meadows but should be balanced with SOM sequestration and other ecosystem services.</div></div>","PeriodicalId":49634,"journal":{"name":"Rangeland Ecology & Management","volume":"98 ","pages":"Pages 283-292"},"PeriodicalIF":2.4,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142746791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Revisiting the Rotational Grazing Dilemma: The Role of Terminology in System Comparison Outcomes","authors":"Tong Wang ,&nbsp;Urs Kreuter","doi":"10.1016/j.rama.2024.06.015","DOIUrl":"10.1016/j.rama.2024.06.015","url":null,"abstract":"<div><div>The contentious rotational grazing debate has continued without resolution for decades with proponents and opponents drawing contradictory evidence-based conclusions. Lack of explicit distinction in grazing systems’ terminology may be an important contributor to the contradictory conclusions, but this issue has received scant attention. To better understand the role of terminology in the grazing management efficacy, we surveyed 870 ranchers in North Dakota, South Dakota, and Texas during January to March 2022. Dividing ranchers into extensive, intermediate, and intensive groups based on their self-identified grazing practice and paddock numbers, we compared a wide range of variables including ranch/rancher characteristics and grazing outcomes among the three groups. We found that the extensive group differed from the intermediate group in 4–15% of the examined variables, whereas the extensive and intensive groups differed in 63–81% of the variables. In terms of ranching outcomes, we found no difference between the extensive and intermediate groups, yet the extensive group differed from the intensive group in 50–100% of the studied outcomes. Such differences highlight the importance of distinguishing between intermediate and intensive grazing management groups when examining the benefits of rotational grazing over continuous grazing, a notable deficiency in much of the previous literature. Our results also point to the need to refine terminology used for grazing management strategies and intensity to ensure consistent comparisons across studies.</div></div>","PeriodicalId":49634,"journal":{"name":"Rangeland Ecology & Management","volume":"98 ","pages":"Pages 246-255"},"PeriodicalIF":2.4,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142746899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fire and Grazing Reduce Invasive Grass Thatch in Rangelands","authors":"Esben L. Kjaer ,&nbsp;Ryan Limb ,&nbsp;Benjamin Geaumont ,&nbsp;Jason Harmon ,&nbsp;Torre Hovick ,&nbsp;Kevin Sedivec","doi":"10.1016/j.rama.2024.06.009","DOIUrl":"10.1016/j.rama.2024.06.009","url":null,"abstract":"<div><div>Rangelands globally are invaded by exotic species. In the northern Great Plains, Kentucky bluegrass (hereafter, “bluegrass”) invades rangelands by forming a thick thatch layer that alters water and nutrient cycling and prevents seed germination by native plants. Consequently, management actions that focus on reducing the bluegrass thatch layer have a greater chance of successfully promoting native plant diversity. To determine how different rangeland management practices impact bluegrass thatch, we measured thatch depth at multiple points across pastures invaded by bluegrass in south-central North Dakota. Each pasture was managed with either patch-burn grazing, modified twice-over rest-rotational grazing (MTORG), or season-long grazing. We also measured thatch in a control pasture that was neither burned nor grazed the previous 5 years. Both the patch-burn grazing and MTORG pastures were designed to increase landscape-level heterogeneity and promote biodiversity. We found that all forms of rangeland management resulted in a thinner thatch layer than our control pasture (3.92 ± 0.27 cm). However, pastures managed with patch-burn grazing had less thatch (1.79 ± 0.03 cm) than those managed with either MTORG (2.60 ± 0.03 cm) or season-long grazing (2.59 ± 0.05 cm). These results suggest that any form of cattle grazing can reduce bluegrass thatch, however fire followed by grazing can further reduce bluegrass thatch. A reduction in thatch resulting from interacting fire and grazing may lessen the impact of bluegrass on rangelands.</div></div>","PeriodicalId":49634,"journal":{"name":"Rangeland Ecology & Management","volume":"98 ","pages":"Pages 414-418"},"PeriodicalIF":2.4,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142746259","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Climate Change Vulnerabilities and Adaptation Strategies for Land Managers on Northwest US Rangelands","authors":"Anna T. Maher ,&nbsp;Holly R. Prendeville ,&nbsp;Jessica E. Halofsky ,&nbsp;Mary M. Rowland ,&nbsp;Kirk W. Davies ,&nbsp;Chad S. Boyd","doi":"10.1016/j.rama.2024.04.012","DOIUrl":"10.1016/j.rama.2024.04.012","url":null,"abstract":"<div><div>Rangelands around the globe are experiencing management challenges associated with existing and emerging stressors, including more frequent and severe fires, woody species expansion, annual grass invasion, heavy, repeated growing season grazing, and climate change. Disturbance is an essential part of rangeland systems. Yet climate change is likely to affect rangelands most directly by increasing the likelihood, severity, and extent of long term, negative impacts from disturbance. We conducted a synthesis of key vulnerabilities to climate change for Northwest US rangelands. These rangelands are projected to become warmer and drier this century, with episodes of more extreme droughts and higher likelihood of more severe fires affecting larger areas. Many of the vulnerabilities identified in our synthesis, such as increased frequency of fire and invasive grass proliferation, can have lasting effects, leading to “undesirable transformations” (substantial and persistent changes in vegetation composition and reductions in ecosystem services). For example, larger, more severe fires have led to the rapid loss of critical Greater sage-grouse habitat and diminished forage production capacity for livestock in some areas, lowering provisioning of ecosystem services, increasing fire management costs, and impacting rural livelihoods. Rangeland managers need guidance connecting climate change projections to on-the-ground management actions. We conclude from our synthesis of climate change vulnerabilities that supporting rangeland recovery is an important climate adaptation approach on Northwest rangelands. Proactive climate adaptation strategies (e.g., supporting soil health and vegetation) and example practices (e.g., establishing climate-adapted perennial plant species) are presented according to key action areas: prepare for, respond to, and recover from disturbance. Identifying specific adaptation needs at more local scales, like the management unit level, may be further refined through proactive planning and experimentation in collaborative settings that allow for resource pooling and foster learning.</div></div>","PeriodicalId":49634,"journal":{"name":"Rangeland Ecology & Management","volume":"98 ","pages":"Pages 399-413"},"PeriodicalIF":2.4,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142192453","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Postwildfire Mechanical Seeding on Soil Properties in Wyoming Big Sagebrush Communities","authors":"Brian M. Morra ,&nbsp;Beth A. Newingham ,&nbsp;Amy C. Ganguli ,&nbsp;Brian K. Howard ,&nbsp;Nancy L. Shaw","doi":"10.1016/j.rama.2024.06.011","DOIUrl":"10.1016/j.rama.2024.06.011","url":null,"abstract":"<div><p>Reduction of vegetation following wildfire in rangelands of the western United States can result in invasion of exotic annual grasses and elevated soil loss to wind erosion. In response to these threats, various mechanical seeding methods (such as drill seeding and mechanical mixing of broadcast seeds) are commonly employed by restoration practitioners. Despite their common use, little information exists about how additional disturbance from mechanical seeding (following wildfire disturbance) may further contribute to soil loss from wind erosion. Here, we compared the effects of mechanical seeding techniques on soil properties following two wildfires occurring in similar climates with contrasting soil textures (silty loam and gravelly loam soils). Using either a rangeland or minimum-till drill to create furrows or mix broadcasted seeds into soils, we quantified wind erosion risk for unburned sites, burned nonseeded sites, and seeded sites according to soil aggregate stability, horizontal sediment flux, surface microtopography, and soil compaction. Effects of mechanical seeding were small relative to those created by wildfire. For burned areas, differences in site stability were greatest between sites. Following wildfire, the largest decrease in site stability occurred in fine-textured soils, where horizontal sediment transport was increased by nearly five orders of magnitude relative to unburned areas. Despite these initial differences, site stability in fine-textured soils may have improved to a greater degree than stability at the coarse-textured site. Furthermore, we found minimal differences between drill types on site stability but, instead, observed that the largest differences in soil properties were created by furrow versus broadcast seeding. The different outcomes of rehabilitation on site stability found here, paired with the spatial extent to which wildfire affects landscapes, highlights the importance of postfire monitoring of site stability in more locations that vary by soil, plant, landscape, and climatic variables.</p></div>","PeriodicalId":49634,"journal":{"name":"Rangeland Ecology & Management","volume":"96 ","pages":"Pages 163-172"},"PeriodicalIF":2.4,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142011309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification of Climatic Refuges of Mouflon Under Future Climate in Central Iranian Protected Areas","authors":"Azita Rezvani,&nbsp;Sima Fakheran,&nbsp;Mahmoud-Reza Hemami","doi":"10.1016/j.rama.2024.06.014","DOIUrl":"10.1016/j.rama.2024.06.014","url":null,"abstract":"<div><p>Habitat destruction is one of the biggest threats to wildlife populations. Climate change may exacerbate the impacts of habitat destruction and alter the distribution of species. We projected the impact of climate change on the distribution of mouflon (<em>Ovis gmelini</em>) in central Iran in 2055 and 2085, evaluated the efficiency of protected areas for protecting this species, and identified potential climatic refugia for this species. We analyzed presence data of mouflon according to climate and topographic factors and generated an ensemble model of habitat suitability based on nine species distribution models. In the modeling process, the most important uncorrelated variables were chosen. Using circuit theory, potential connectivity between habitat patches was estimated. To assess the impact of climate change on the study area in 2055 and 2085, two shared socioeconomic pathways (SSPs), SSP 2.6 and SSP 8.5, were used based on the global circulation models. Based on the climatic suitability model, approximately 34.11% of protected areas were recognized as suitable habitats for mouflon. In the forecasted climate conditions, approximately 3.30% of suitable habitats would become unsuitable and approximately 9.36% of the current protected areas will lose their efficiency in supporting this species. In addition, climate change may reduce habitat connectivity for mouflon in the future. We conclude that the development of the network of protected areas and attention to habitat connectivity are necessary for the future migration and survival of this species; therefore, conservation planning should consider the future potential of protected/unprotected areas in supporting mouflon populations.</p></div>","PeriodicalId":49634,"journal":{"name":"Rangeland Ecology & Management","volume":"96 ","pages":"Pages 173-182"},"PeriodicalIF":2.4,"publicationDate":"2024-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142011310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Grazing Intensity Controls the Seasonal Utilization of Functionally Diverse Patches by Mediating Herbivore Selectivity","authors":"Nicolas Caram ,&nbsp;Felipe Casalás ,&nbsp;Pablo Soca ,&nbsp;Marcelo O. Wallau ,&nbsp;Lynn E. Sollenberger ,&nbsp;Mónica Cadenazzi ,&nbsp;Pablo Boggiano","doi":"10.1016/j.rama.2024.06.006","DOIUrl":"10.1016/j.rama.2024.06.006","url":null,"abstract":"<div><p>Understanding the mechanistic link between plant functional traits and foraging patterns across seasons and grazing intensities is crucial for implementing sustainable grazing systems and predicting ecological successions. We assessed the interaction effects of grazing intensity, season, and leaf functional traits on herbivore grazing patterns in a native grassland composed of functionally diverse patches in four 10–14 ha paddocks managed under lenient or moderate grazing intensities. Seasonal botanical composition was estimated in permanent 20 × 20 cm patches. Defoliation events of species in patches were recorded every 7–10 d, four times during summer-autumn, and five times during winter and spring. Leaf dry matter content, specific area, tensile strength, and width of dominant grass species were measured seasonally, and species were allocated to functional groups. The proportion of total defoliation events occurring in each functional group and their selectivity index were estimated for each period and season. We tested the relationship between trait community weighted mean in the pasture and that grazed by cattle for each quadrant and period within seasons. Cows focused grazing on resource-acquisitive strategy species with wider and more tender leaves during summer-autumn under both grazing intensities. As herbage mass and accumulation decreased during winter, cows shifted their foraging strategy toward shorter patches and previously rejected, tougher-thinner leaves and resource-conservative strategy species stockpiled from summer-autumn, not overgrazing the resource-acquisitive species. However, this general pattern was modulated by grazing intensity; cows grazed taller patches and more tender and wider-leaved species under lenient than moderate grazing intensity. Thus, the spatiotemporal heterogeneity of desired and rejected stockpiled patches of different functional groups was managed by integrating seasonality, grazing intensity, and leaf functional traits. Therefore, the general principle of foraging selectivity toward desired species can be altered by management practices and inherent species attributes, maintaining communities of species of different ecosystem functions in equilibrium.</p></div>","PeriodicalId":49634,"journal":{"name":"Rangeland Ecology & Management","volume":"96 ","pages":"Pages 152-162"},"PeriodicalIF":2.4,"publicationDate":"2024-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142011308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}