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1.
黄河流域甘肃段植被覆盖度时空变化及对气候因子的响应   总被引:3,自引:5,他引:3  
[目的]分析黄河流域甘肃段2000—2018年植被覆盖度变化的时空演变规律,探讨该区域植被覆盖度的变化对气候的响应机制,为该区域生态环境与社会经济的协调可持续发展和进一步落实生态环境保护、建设及恢复提供科学依据。[方法]基于2000—2018年的MODIS NDVI数据、气象数据,采用线性趋势分析和相关性分析等方法,对黄河流域甘肃段植被覆盖度的时空变化特征及与气候因子之间的关系进行分析。[结果]①空间上,近19 a研究区植被覆盖度自西南向东北在不断降低,以甘南州的植被覆盖状况最好;植被覆盖度改善面积占36.64%,主要分布于兰州市北部、临夏州、定西市、庆阳市、平凉市大范围区域、天水市南部等,而退化面积占4.2%,主要集中于甘南州等地区。②时间上,研究区植被覆盖度以2013年为界呈现"先持续增加后波动减少"的变化趋势,但整体在不断增加;以平凉市的增加速度最快,平均每年增长0.96%。③研究区植被覆盖度对降水量变化的响应敏感,与降水量呈现显著的正相关关系。[结论]研究区植被覆盖度空间差异明显,2000—2018年植被以改善为主,降水是影响这些区域植被改善的有利因素,降水状况的改善对研究区生态环境建设与修复至关重要。  相似文献   

2.
1981—2012年黄土高原植被覆盖度时空变化特征   总被引:3,自引:0,他引:3  
植被覆盖度是反映植被覆盖状况最直接的指标。基于1981—2012年的MODIS影像,采用像元二分模型反演黄土高原植被覆盖度,分析了黄土高原各省区、典型流域及土壤侵蚀类型区生长季(5—10月)的植被覆盖度时空动态变化。结果表明:1981—2012年期间,黄土高原生长季植被覆盖度由31%增加到50%,呈显著上升趋势,但各区域增长幅度不同。2001年之前,黄土高原植被覆盖度平均为36%,年际间以小幅波动为主;之后,该区生长季年平均植被覆盖度为41%,年际间呈显著增加趋势。按省区,河南省植被覆盖度增幅最大,陕西省次之,内蒙古、宁夏增幅不明显且覆盖度在20%左右波动。按典型流域,延河流域增幅最大,窟野河流域增幅最小。按土壤侵蚀类型,水力侵蚀区植被覆盖度增长较快,风力侵蚀区则变化不明显。按植被覆盖度构成,低覆盖度面积比例减少,高覆盖度面积比例增加,其中黄土高原丘陵沟壑区植被覆盖度增加趋势最为明显,植被恢复成效显著。  相似文献   

3.
[目的] 对赣江上游植被覆盖度时空演化及其对气候变化响应的研究,为区域的生态环境保护提供科学依据和数据支撑。[方法] 基于MODIS NDVI数据,结合年平均气温和年降水量数据,运用趋势分析、变异系数、Hurst指数与相关分析等方法对赣江上游2000—2018年的植被覆盖度时空演化及其对气候变化的响应进行了分析。[结果] ①赣江上游植被覆盖度呈显著增加趋势,增速为5.21%/10 a,空间上呈现四周高中间低的特征,且以高植被覆盖为主;研究区植被覆盖度呈极显著和显著增加的分别占25.59%和39.7%,极显著和显著减少的分别占1.32%和2.46%,而变化不显著的占57.84%;②研究区植被覆盖总体上比较稳定,平均变异系数为14.73%;Hurst分析显示赣江上游植被变化反持续性要强于持续性,总体上以弱反持续性为主;③研究区植被生长总体上受气温影响强于降水量,但存在空间差异。[结论] 赣江上游植被覆盖度变化较小,未来将呈微弱下降趋势,气温是影响植被生长的主要气候因子。  相似文献   

4.
[目的]退耕还林还草工程实施以来,陕西省植被覆盖度明显提高。然而,省级尺度上植被覆盖度的增加一定程度上掩盖了部分市、县级区域植被覆盖度下降的实事,当前迫切需要加强对不同空间尺度植被覆盖变化及其驱动因素的研究。[方法]基于MODIS NDVI数据计算了陕西省植被覆盖度,分析了2000—2020年陕西省、地区、市和县四级尺度植被覆盖度时空变化趋势。[结果]2000—2020年陕西省植被平均覆盖度为64.3%±2.1%,增长率为0.24%/a;陕北植被覆盖度平均为37.6%±4.4%,增长率为0.63%/a;陕南植被覆盖度平均为89.6%±1.2%,增长率为0.13%/a;关中植被覆盖度平均为70.6%±3.5%,下降率为-0.18%/a。延安市、榆林市、铜川市、宝鸡市、安康市、商洛市的植被覆盖度呈持续增加趋势,而西安市、渭南市、咸阳市和汉中市的植被覆盖度呈先增加后下降趋势;全省有72.3%的区县植被覆盖度呈增加趋势,有22.3%的区县植被覆盖度变化方向与所在市相反。在不同空间尺度上,陕西省植被覆盖度增速均表现为2000—2010年高于2010—2020年,这与两个时期的造林面积差异有关。[...  相似文献   

5.
黄土高原植被变化与恢复潜力预测   总被引:5,自引:2,他引:5       下载免费PDF全文
采用GIS技术与地统计方法,基于黄土高原2000—2018年的MODIS遥感影像,选取归一化植被指数探讨研究区植被时空变化特征,采用相似生境法预测黄土高原植被恢复潜力。结果表明:黄土高原2000—2018年低植被盖度区域面积减少,高植被覆盖度面积不断增加。黄河中游头道拐至龙门区间植被变化最为显著,平均增长速率为0.015~0.050/a,其中,延河上游、清涧河及秃尾河流域的植被盖度增长速率最高,均超过了0.015/a。受城市化影响,汾渭平原的下游干流区植被盖度显著降低。相似生境法预测黄土高原未来植被恢复潜力的空间差异性显著,东南部地区植被盖度接近或达到最大恢复潜力,无恢复空间;在丘陵沟壑区和风沙区的交错地带部分地区植被盖度较现状仍有25%~50%的提升潜力。由于黄土高原植被受退耕还林草工程影响,人工植被干扰强烈,受到该区降雨与水分承载力限制,未来植被恢复需调整植被类型、优化植被结构与格局,提升区域生态系统功能。本研究结果可为黄土高原未来植被恢复与水土保持规划与布局提供理论与方法支撑。  相似文献   

6.
黄土高原1999年开始的退耕还林(草)工程,对植被覆盖与土地利用结构产生了深刻影响,评估黄土高原未来植被恢复潜力、植树造林适宜区以及土地利用变化,对黄土高原生态保护和高质量发展具有重要意义。该研究基于北洛河流域2020年下垫面状况,借鉴"相似生境法",对不同地貌类型区的未来恢复潜力、植树造林适宜区与土地利用变化进行了分析。结果表明:1)丘陵沟壑区目前平均植被盖度为61.9%,未来20~30 a仍有9.2%左右的上升空间,植被可恢复土地面积约占丘陵区的36.4%。土石山林区尚有11.5%的土地面积具有恢复余地,高塬沟壑区与阶地平原区植被盖度恢复余地很小。2)未来土地利用变化面积主要集中在丘陵沟壑区,与2020年相比,其耕地将减少47.4%,而林地与草地会增加0.7%与15.8%。土石山林区耕地将减少23.0%,林地与草地分别会增加0.2%与36.0%。3)基于"适地适树"原则下的情景模拟,高塬沟壑区与阶地平原区分别有279.16、233.73 km2面积可植树造林,而丘陵沟壑区大片可退耕土地适宜于自然恢复。结果表明,丘陵沟壑区仍是未来生态恢复重点关注区域,是黄河流域生态保护和高质量发展的热点区域。  相似文献   

7.
文帆  陈秋计  黄兰  王志国 《水土保持通报》2023,43(6):304-310,323
[目的] 分析彬长矿区植被覆盖度变化特征及空间分布影响因素,判别矿区的生态状况断,为矿区复垦和生态恢复提供科学参考和理论依据。[方法] 基于Google Earth Engine云平台,获取1986—2021年30 m分辨率Landsat Surface Reflectance Tier 1 Data(地表反射率数据),基于像元二分模型,采用趋势分析法、F检验等方法对彬长矿区植被覆盖度多年时空变化作出定量分析;在此基础上运用地理探测器对植被覆盖度的空间分异性进行地理因子解析。[结果] ①1986—2021年彬长矿区植被覆盖度改善状况较好,总体呈现增长趋势,平均增长率为0.64%/a;研究区多年平均植被覆盖度水平较高,中覆盖度及以上面积占87.14%,空间分布上呈现“东南高,西北低”的特点。②植被覆盖度变化趋势上,研究区以显著改善区域为主,其面积所占比例为56.65%,但仍有些许地区植被显著退化,主要集中在靠近城市河流道路区域。③各因子对植被覆盖度的影响大小排序为:坡度>高程>年降水>GDP>人口密度>年均温>植被类型>土壤类型,坡度与年降水交互作用对植被覆盖度空间分异性影响最强。[结论] 1986—2021年彬长矿区植被覆盖状况良好,整体呈现显著增长趋势,植被改善情况明显,坡度为影响研究区植被覆盖度空间分异性的主导因子。  相似文献   

8.
[目的]砒砂岩区是黄河流域土壤侵蚀最为严重的区域,探讨该地区植被覆盖度变化状况及其影响的驱动因素,以期为该区植被恢复及生态重建工作提供科学参考。[方法]基于2000—2022年的MOD13Q1 NDVI数据,运用Sen趋势、Mann-Kendall显著性检验、Hurst指数、残差分析等方法分析砒砂岩区研究期内的植被覆盖度时空变化趋势,并探究植被覆盖度与气候因子及人类活动的响应关系。[结果](1)2000—2022年砒砂岩区植被覆盖度增加,增速为4%/a(p<0.05);空间尺度上,研究区植被覆盖度在3个区有明显的分异效果,整体呈现“南高北低,东高西低”的分布态势;(2)研究期内,砒砂岩区植被覆盖度与降水量呈正相关区域占总面积的66.30%,负相关区域占总面积的33.70%;与气温呈正相关区域占总面积的92.19%,负相关区域占总面积的7.81%;(3)残差分析结果表明,2000—2011年人类活动多以负面影响为主,2012—2022年人类活动多以正向影响为主。[结论]研究期间砒砂岩区植被覆盖度呈显著上升趋势,与年均气温的相关性高于年降雨量,且一系列生态保护工程为改善植被情况做出了...  相似文献   

9.
基于RS与像元二分模型的近20 a宁夏植被覆盖研究   总被引:3,自引:0,他引:3  
[目的]探讨近20a宁夏植被变化特征及其对气候的响应情况,为了解区域生态变化态势,评估生态工程成效提供理论基础和科学依据。[方法]利用1992,2000,2006和2012年的TM数据,基于植被指数估算植被覆盖度的原理,运用像元二分模型,对宁夏植被覆盖度进行遥感估算和动态监测。[结果]宁夏植被覆盖呈现南北好,中部差的空间分布特点;近20a来宁夏的植被覆盖度表现出明显的增加趋势,即低植被覆盖区的面积在逐渐减少,中、高植被覆盖区的面积增加了6 434km2,全区平均植被覆盖度提高6%,其中扬黄灌区及南部山区植被覆盖增加幅度较大。[结论]宁夏植被覆盖度的增加主要得益于近年来实施的一系列植被保护和生态恢复工程,而降水量的变化则是引起植被覆盖度年际波动的主要因素。  相似文献   

10.
[目的] 研究贵州省北盘江流域NDVI变化及其与地形梯度、人口分布的关系,为喀斯特地区植被恢复、退耕还林开展、国土空间优化整治等提供科学参考。[方法] 采用2000—2018年贵州省北盘江流域NDVI数据,分析其时空变化特征及与海拔、坡度、人口密度等影响因素的相互关系。[结果] ①2000—2018年北盘江流域NDVI值总体呈上升趋势,且年均增长稳定,植被呈现不断恢复的趋势。②2000年北盘江流域NDVI空间分布在东南部最高,在西北部最低,NDVI高值在中部地区分布较为破碎,至2018年各地区NDVI值差距显著缩小,其中在西北部和中部NDVI低值区转变最为明显。③2000—2018年北盘江NDVI显著减少、轻微减少及轻微增加的地区面积较少,面积比例不足10%;而显著增加地区面积为19 986.04 km2,比例为90.93%。④2000—2018年,北盘江流域NDVI的海拔效应表现为阶段变化特点,其中2000—2010年NDVI值随着海拔的上升总体呈现下降趋势;2010—2018年NDVI值随着海拔的上升总体呈现上升趋势;NDVI值随坡度增加表现为上升—下降趋势;而NDVI值随人口密度增加呈降低趋势。[结论] 地形因子奠定植被生长条件,而社会和人为因子对NDVI值变化影响较大。  相似文献   

11.
低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响   总被引:2,自引:2,他引:0  
【目的】以富士(Fuji)、 秦冠(Qinguan)嫁接在平邑甜茶(Malus hupehensis Rehd.)上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水(ZZ)、 低氮正常水(DZ)、 正常氮干旱(ZG)、 低氮干旱(DG)。氮素和水分均设置两个水平,分别为正常氮(6 mmol/L NO-3-N)、 低氮(0.3 mmol/LNO-3-N)、 正常供水(保持盆中砂子相对含水量为饱和含水量的80%~85%)、 干旱处理(保持盆中砂子相对含水量为饱和含水量的60%~65%)。【结果】富士和秦冠的生物量(茎和叶)、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG),并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG); 氮、 钾元素含量在植株各部位的分布顺序依次是叶>根>茎,磷元素则是根>叶>茎;光合氮素利用效率(PNUE)和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水(DZ)处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱(DG)处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。  相似文献   

12.
Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions.  相似文献   

13.
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.  相似文献   

14.
We have studied the effect of anaerobically digested (ADMSW) and composted municipal solid waste (CMSW) on mineralization and foodweb dynamics to verify the hypothesis that ADMSW would immobilize N right after addition to soil in contrast to addition with CMSW. Another hypothesis was that the mesofauna (enchytraeids and microarthropods) would stimulate N release from the decomposer community. We measured excretion of -N and urea-N from the mesofauna and hypothesized that enchytraeids would release urea. ADMSW and CMSW were amended to pots with sandy loam and barley. The pots were divided into treatments with or without mesofauna. Mesofauna, plant N and biomass, soil N and ergosterol (fungal biomass) were measured over a 113-day period of four equidistant samplings. Soil respiration, N mineralization and N release by the mesofauna were modelled from concurrent studies. ADMSW- and CMSW-treated soils initially (<20 days) immobilized N. The amendments did not increase plant growth substantially, and this was probably due to N-limitation in the early stages of plant growth. Enchytraeid abundance was about three times higher in ADMSW- than CMSW-treated soils, indicating that ADMSW contained more labile compounds, bacteria, and microfauna. The mesofauna did not affect N-content, but the cumulated -N excreted by the mesofauna was estimated to be substantial and about one-fifth of total plant N in ADMSW. An explanation for this discrepancy might be that in the absence of the mesofauna, other members of the detrivore and microbivore community performed the mesofauna’s function. Neither enchytraeids nor microarthropods excreted urea.  相似文献   

15.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

16.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

17.
“Wicked” problems are those that are complex and that change when solutions are applied. Many conflicts in conservation fall into this category. The study approached the problem of how to constrain the apparent wickedness of a problem in the conservation management of a species by using simple empirical indicators to carry out iterative assessment of the risk to a population and to document how this risk evolves in relation to the addition of new data and the implementation of management actions. Effects of high levels of uncertainty within data and also concerning population structure were examined through stochastic simulation and by exploration of scenarios. Historical trends in the example used, the Steller sea lion, showed rapid declines in abundance in some regions during the 1980s. The current total population is 130,000-150,000 Steller sea lions through Alaska and British Columbia and this number has been stable since about 1990 in spite of regional differences in population dynamics. Regional differences in the sequence of changes in the number of pups and non-pups, suggested that an internal re-distribution of juveniles could have happened between 1980 and 1990. Current productivity also appears close to the long-term mean. Stochastic population projection using various scenarios showed that, based upon this history, the risk of extinction for the population has declined and is below reasonable thresholds for considering the population to be endangered. The trends in risk suggest that management actions taken since 1990 have probably been effective. Consequently, the conservation management objectives for the Steller sea lion are probably being met. The approach provides a mechanism, based upon experience and scenario analysis, for exploring future policy options and may help to constrain the debate amongst stakeholders about the cost-benefit trade-offs associated with different options.  相似文献   

18.
Nutrient distributions under no tillage (NT) compared with conventional disk-and-bed tillage (CT) management in the warm, humid region of the southeastern USA need to be assessed so that future placement, quantity, and type of fertilizers can be altered, if necessary, to efficiently match crop demands. We determined soil-profile distributions of pH, N, P, S, K, Ca, Mg, Na, Zn, Fe, Mn, and Cu to a depth of 0.9 m at the end of 8.5 years of continuous CT and NT management on a Weswood silty clay loam (fine, mixed, thermic Fluventic Ustochrept) in southcentral Texas. Most dramatic changes occurred within the 0–0.05 m depth, where soil under NT had lower pH, Fe, and Cu than under CT, but greater P, K, Zn, and Mn. Greater P and K under NT than under CT also occurred below the till-zone (0.15–0.3 m). At a depth of 0–0.3 m, soil under NT contained greater amounts of extractable P, K, Zn, Fe, Mn, and Cu than under CT. Nitrogen fertilization had little effect on nutrient distributions, except resulting in greater extractable K at 0–0.05 m and greater nitrate at 0–0.15 m. Few changes in soil-profile distributions were observed for extractable S, Ca, Mg, and Na. Long-term continuous use of NT on this fine-textured, high-fertility (except for N) soil had no apparent adverse effects on nutrient distributions relative to CT, but enhanced conservation and availability of P, K, Zn, Fe, Mn, and Cu near the soil surface where crop roots proliferate.  相似文献   

19.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

20.
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.  相似文献   

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