Fire and grazing interaction in a subhumid grassland: Effects on a dominant tussock grass

IF 2 3区环境科学与生态学 Q3 ECOLOGY

Applied Vegetation Science Pub Date : 2024-07-15 DOI:10.1111/avsc.12795

Luis López-Mársico, Felipe Lezama, Alice Altesor

{"title":"Fire and grazing interaction in a subhumid grassland: Effects on a dominant tussock grass","authors":"Luis López-Mársico, Felipe Lezama, Alice Altesor","doi":"10.1111/avsc.12795","DOIUrl":null,"url":null,"abstract":"<div>\n \n \n <section>\n \n <h3> Questions</h3>\n \n <p>Herbivory and fire are the main disturbance drivers in open ecosystems. The aim of this study was to evaluate the effects of fire, cattle grazing, and their interaction on structural traits and the Normalized Difference Vegetation Index (NDVI) of the tussock grass <i>Saccharum angustifolium</i>, and its temporal dynamics in a subhumid grassland.</p>\n </section>\n \n <section>\n \n <h3> Location</h3>\n \n <p>Grasslands of the Eastern Hills, Uruguay.</p>\n </section>\n \n <section>\n \n <h3> Methods</h3>\n \n <p>We set three blocks (four plots of 300 m<sup>2</sup> each) in a homogeneous grazed area dominated by <i>S. angustifolium</i> within a protected area. Each block presented the combinations that emerged from the two levels of cattle grazing (grazed/ungrazed) and burning (burned/unburned) factors. The experimental burning was carried out in the spring. Clump volume, number of flowering culms, NDVI of <i>S. angustifolium</i>, and soil variables were measured for 2 years.</p>\n </section>\n \n <section>\n \n <h3> Results</h3>\n \n <p>Burning efficiency (plant biomass burned of the total available) was 82%, burn intensity ranged from 178–610 kW m<sup>−1</sup>, and the soil temperature increased 40% compared with pre-fire measurements. The volume of <i>S. angustifolium</i> clumps decreased with fire, and the difference between burned–unburned plots decreased with time. The burned–ungrazed treatment increased the number of <i>S. angustifolium</i> flowering culms. NDVI of <i>S. angustifolium</i> clumps increased 50% with fire, and then decreased with time. Soil temperature was higher in burned treatments, and moisture was higher in unburned treatments on some dates. Bulk density, for the 0–5-cm depth, was 9% higher in burned than in unburned plots irrespective of grazing.</p>\n </section>\n \n <section>\n \n <h3> Conclusions</h3>\n \n <p>Our results provide new data in favor of the management practice carried out by ranchers in Uruguayan grasslands dominated by <i>S. angustifolium</i>. Our data complement the evidence that a fire–grazing interaction can maintain grasslands in different phases of a stable state. Our results constitute a useful contribution for the managers/authorities of the protected area, and can be extrapolated to other tussock grass-dominated grassland areas.</p>\n </section>\n </div>","PeriodicalId":55494,"journal":{"name":"Applied Vegetation Science","volume":"27 3","pages":""},"PeriodicalIF":2.0000,"publicationDate":"2024-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Applied Vegetation Science","FirstCategoryId":"93","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1111/avsc.12795","RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ECOLOGY","Score":null,"Total":0}

引用次数: 0

Abstract

Questions

Herbivory and fire are the main disturbance drivers in open ecosystems. The aim of this study was to evaluate the effects of fire, cattle grazing, and their interaction on structural traits and the Normalized Difference Vegetation Index (NDVI) of the tussock grass Saccharum angustifolium, and its temporal dynamics in a subhumid grassland.

Location

Grasslands of the Eastern Hills, Uruguay.

Methods

We set three blocks (four plots of 300 m² each) in a homogeneous grazed area dominated by S. angustifolium within a protected area. Each block presented the combinations that emerged from the two levels of cattle grazing (grazed/ungrazed) and burning (burned/unburned) factors. The experimental burning was carried out in the spring. Clump volume, number of flowering culms, NDVI of S. angustifolium, and soil variables were measured for 2 years.

Results

Burning efficiency (plant biomass burned of the total available) was 82%, burn intensity ranged from 178–610 kW m⁻¹, and the soil temperature increased 40% compared with pre-fire measurements. The volume of S. angustifolium clumps decreased with fire, and the difference between burned–unburned plots decreased with time. The burned–ungrazed treatment increased the number of S. angustifolium flowering culms. NDVI of S. angustifolium clumps increased 50% with fire, and then decreased with time. Soil temperature was higher in burned treatments, and moisture was higher in unburned treatments on some dates. Bulk density, for the 0–5-cm depth, was 9% higher in burned than in unburned plots irrespective of grazing.

Conclusions

Our results provide new data in favor of the management practice carried out by ranchers in Uruguayan grasslands dominated by S. angustifolium. Our data complement the evidence that a fire–grazing interaction can maintain grasslands in different phases of a stable state. Our results constitute a useful contribution for the managers/authorities of the protected area, and can be extrapolated to other tussock grass-dominated grassland areas.

Abstract Image

查看原文本刊更多论文

亚湿润草原上火灾与放牧的相互作用：对优势草丛的影响

问题食草动物和火灾是开放生态系统的主要干扰因素。本研究的目的是评估火灾、牛群放牧及其相互作用对亚湿润草地中鹅掌楸草（Saccharum angustifolium）的结构特征、归一化植被指数（NDVI）及其时间动态的影响。地点乌拉圭东部丘陵的草地。方法我们在一个保护区内以 S. angustifolium 为主的同质放牧区设置了三个区块（四个小区，每个小区 300 平方米）。每个区块由放牧（放牧/未放牧）和焚烧（焚烧/未焚烧）两个因素组成。试验性焚烧在春季进行。连续两年测量了丛茎体积、开花茎秆数量、S. angustifolium 的 NDVI 和土壤变量。结果燃烧效率（燃烧的植物生物量占总生物量的比例）为 82%，燃烧强度为 178-610 kW m-1，土壤温度比燃烧前的测量值提高了 40%。S.angustifolium丛生灌木的体积随着火灾的发生而减少，烧毁与未烧毁地块之间的差异随着时间的推移而缩小。烧荒处理增加了 S. angustifolium 花茎的数量。S. angustifolium丛生植株的NDVI在火灾后增加了50%，然后随着时间的推移而减少。在某些日期，烧毁处理的土壤温度较高，而未烧毁处理的土壤湿度较高。无论放牧与否，烧毁地块 0-5 厘米深度的体积密度比未烧毁地块高 9%。结论我们的研究结果提供了新的数据，支持牧场主在以 S. angustifolium 为主的乌拉圭草原上采取的管理措施。我们的数据补充了火与放牧相互作用可使草原保持不同阶段稳定状态的证据。我们的研究结果为保护区的管理者/当局做出了有益的贡献，并可推广到其他以簇生草为主的草原地区。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Applied Vegetation Science 环境科学-林学

CiteScore

6.00

自引率

10.70%

发文量

审稿时长

3 months

期刊介绍： Applied Vegetation Science focuses on community-level topics relevant to human interaction with vegetation, including global change, nature conservation, nature management, restoration of plant communities and of natural habitats, and the planning of semi-natural and urban landscapes. Vegetation survey, modelling and remote-sensing applications are welcome. Papers on vegetation science which do not fit to this scope (do not have an applied aspect and are not vegetation survey) should be directed to our associate journal, the Journal of Vegetation Science. Both journals publish papers on the ecology of a single species only if it plays a key role in structuring plant communities.