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1.
基于投入视角的山东省农地利用碳排放与经济发展脱钩研究 总被引：2，自引：0，他引：2
[目的]分析山东省2000—2012年农地利用碳排放与经济发展关系,为该区碳减排工作和农业相关政策的制定提供理论依据。[方法]基于农地利用的投入视角,采用碳排放计算模型和脱钩弹性测算方法,计算了2000—2012年山东省17个地级市农地利用碳排放量,及其与经济发展的脱钩关系,将该省划分为不同的脱钩类型,揭示两者的时空演变规律。[结果](1)2000—2012年山东省碳排放量增量显著,由7.12×106 t升至8.39×106 t,年均增长9.77×104 t,潍坊市的碳排放量最大,莱芜市的排放量最小。(2)山东省农地利用碳排放强度存在显著的空间差异性,呈东高西低的空间分异格局。(3)山东省主要表现为强脱钩与弱脱钩并存的状态,并以强脱钩为主。(4)山东全省脱钩类型空间分布规律较明显,强脱钩分布广泛,弱脱钩集中于西南地区。[结论]山东省农地利用碳排放和经济发展存在一种科学的、合理的脱钩弹性关系,但仍需加大对于农地利用的科技投入,合理分配农用物质的投入比例。 相似文献
2.
乌鲁木齐市土地利用结构与碳排放的关联测度研究 总被引：1，自引：0，他引：1
[目的]对乌鲁木齐市的土地利用结构与碳排放量的关系进行测度,分析一定时间范围内二者的关联度及其变化特征,从而探索土地利用碳减排途径,为乌鲁木齐市合理利用土地与生态、经济、社会效应的同步提升提供参考。[方法]基于乌鲁木齐市2001—2015年的土地利用变更数据和能源消耗数据,分别计算出碳排放总量、碳排放强度和人均碳排放量,并构建灰色关联度模型,测算乌鲁木齐市土地利用结构与碳排放总量、碳排放强度、人均碳排放量的关联系数和关联度。[结果]2001—2015年乌鲁木齐市碳排放量由8.31×10~6 t增加到2.10×10~7 t,增加了近2.6倍;土地利用结构与碳排放总量、碳排放强度和人均碳排放量三者关联度最高的分别是交通运输用地(0.730 8)、牧草地(0.765 1)和园地(0.821 5);建设用地与碳排放量关联度大。[结论]土地利用结构与碳排放的关系密切,通过科学合理地利用土地利用结构变化对碳收支的影响作用对土地利用结构进行调整,从而实现控制碳排放量是可行的。 相似文献
3.
[目的]分析淮南矿区2000—2020年土地利用碳源/碳汇时空格局分布特征,为淮南市国土空间规划及未来低碳调控政策制定提供依据。[方法]以淮南矿区为研究对象,选取2000,2010,2020年3期土地利用数据,以格网尺度量化不同土地利用变化发展阶段下碳源/碳汇/碳排放的时空格局,基于冷热点分析碳源/碳汇/碳排放的空间格局。[结果](1)2000—2020年,土地利用类型由单一用地为主转换多种土地利用类型同时发生,其中,建设用地面积增大,导致碳源效应增强,碳汇效应相对减弱,碳排放量持续增加,碳源年增加量为2.76×106 t,碳汇年增加量仅为130 t,碳排放年增加量为2.76×106 t;(2)碳源和碳排放空间分布特征基本一致,中部建成区和西北矿区是碳源和碳排放的主要集中区,碳汇主要聚集在东部、西部边缘区和西部部分矿区;(3)中部建成区是碳源和碳排放的显著热点、热点区域,以显著热点变化特征为主;显著冷点和冷点主要分布在研究区东部、西部边缘区域和西北部分矿区。[结论]淮南矿区的碳减排和低碳效应需要着重关注北部大面积的平原耕地区域,控制该区域矿区... 相似文献
4.
陕西省土地利用碳排放影响因素及脱钩效应分析 总被引：5，自引：0，他引：5
通过测算陕西省2001—2014年土地利用碳排放量,采用LMDI分解法探讨了土地利用碳排放变化的影响因素,并基于因素分解的结果构建脱钩弹性分解量化模型对经济增长和土地利用碳排放的脱钩效应进行分析。主要结论如下:（1）2001—2014年,陕西省土地利用碳排放量呈逐年递增趋势,13年间上升163%。（2）能源强度是唯一抑制土地利用碳排放增加的负效应因素,正效应因素对陕西省土地利用碳排放增加的贡献值由大到小依次为经济规模效应 > 能源碳排放强度效应 > 人口规模效应 > 土地规模效应;（3）各影响因素对土地利用碳排放与经济增长脱钩的贡献由大到小依次为经济规模效应 > 能源强度效应 > 能源碳排放强度效应 > 人口规模效应 > 土地规模效应,且能源强度效应对经济增长与土地利用碳排放脱钩状态的改善具有积极作用。研究结论有利于清晰了解土地利用碳排放影响因素及其影响经济增长和土地利用碳排放脱钩的内在作用机理,从而得出相应的碳减排政策启示。 相似文献
5.
基于脱钩理论的烟台市碳排放效应分析 总被引：2，自引：4，他引：2
[目的]通过分析烟台市2000—2011年碳排放与经济发展之间的关系,为烟台市碳减排及发展低碳经济提供参考。[方法]基于土地利用碳源/碳汇研究的理论框架和计算模型,首先对烟台市土地利用、能源消费等数据进行分析,计算了不同土地利用类型的碳源/汇。然后利用Tapio脱钩模型分析该区碳排放与经济发展之间的脱钩弹性关系。[结果](1)建设用地是主要碳源,其面积与净碳排放量成倒U型库兹涅茨曲线关系。(2)林地为主要碳汇,其他用地影响较小且主要表现为碳汇。(3)烟台市净碳排放量在2001—2011年持续增长,年均增长率不断降低。[结论]烟台市碳减排工作已取得一定的成效,但减排形势依然严峻。其经济发展3个阶段(连接阶段、脱钩阶段Ⅰ和脱钩阶段Ⅱ)分别对应于其碳排放的高速增长、较快增长、稳定阶段这3阶段。 相似文献
6.
基于投入视角的农业碳排放与经济增长的脱钩效应分析——以河南省为例 总被引：5，自引：0，他引：5
基于农业生产中的6个方面测算了河南省1993—2014年的农业碳排放量和排放强度。22年来河南省农业碳排放总量由1993年的495.12万t增加到2014年的1 704.13万t,年均增长6.12%,总体上呈"高速—低速—高速—低速"四阶段演化特征,农业碳排放强度从1993年的720.60kg/hm~2增加到2014年的2 080.23kg/hm~2,年均增长5.28%。河南省农业碳排放总量与经济发展呈典型的倒"U"型曲线关系,且开始出现拐点,但不明显。农业碳排放总量的组成结构随时间变化,从平均占比情况来看碳排放组成依次为农村用电、化肥、农膜、农药、农用柴油和翻耕。运用Tapio脱钩模型计算了河南省农业碳排放的脱钩弹性系数,结果显示,2004年前农业碳排放与农业经济发展的脱钩关系呈现弱脱钩、扩张负脱钩、扩张连接和强负脱钩4种弹性特征并存,2004年后以弱脱钩为主导,占比81.82%,说明近年来河南省在农业碳减排方面取得了一定成效,未来河南省还须采取措施,从根本上实现农业碳排放与农业经济增长脱钩。 相似文献
7.
[目的]从水足迹视角剖析平塘县农业经济增长与农业水资源利用耦合作用机理,为喀斯特峰丛洼地生态治理提供参考资料。[方法]利用联合国粮农组织推荐CROPWAT 8.0软件,测算平塘县2002—2015年农业水足迹,运用脱钩理论,分析平塘县2001—2015年农业发展与农业水资源利用脱钩态势。[结果](1)2002—2015年平塘县水足迹与生产总值整体上呈波动上升趋势,但其增长率波动性较大;(2)从Tapio脱钩弹性指数来看,现阶段农业经济增长与农业水资源消耗关系尚不稳定,农业水资源不可持续性利用状态仍存在;(3)2007年为脱钩关系较为理想年份,其次是2008年,协调状况最差是2006,2002—2015年脱钩态势系整体上,呈倒U形变化趋势;(4)从面积来看,研究时段弱脱钩面积比重范围为0%~97.9%(2010年最大,2013年其次,2007和2011年最小),强脱钩面积比重范围为0%~100%(2007年最大,2008年其次,2010年最小),衰退脱钩面积比重范围为0%~49.7%(2011年为49.7%,其他年份为0)。[结论]总体上,平塘县农业经济增长与农业水资源利用协调状况不佳。 相似文献
8.
在“双碳”目标和保护生态环境的双重约束下，研究土地利用变化引起的碳排放与生态系统服务价值之间的交互关系对促进碳中和目标实现与区域高质量发展具有重要意义。选取长株潭城市群主城区为研究对象，以2000—2020年5期土地利用、能源消耗和社会经济等数据为基础，综合运用网格分析法和双变量空间自相关模型探索土地利用碳排放与生态系统服务价值的时空演变特征及交互作用规律。结果表明：(1)2000—2020年各土地利用类型间发生不同程度的转移，其中，耕地与林地分别减少392.77,268.10 km2,建设用地增加661.80 km2。(2)2000—2020年长株潭城市群的净碳排放量为正，整体表现为碳排放，且净碳排放量显著增加，由1 099.84×104 t增长到4 109.21×104 t;碳排放强度呈现中心高、边缘低的空间分布特征。(3)ESV缓慢降低，由392.06×108元下降到292.86×108元，下降幅度为5.34%;ESV强度整体呈现湘江流域高、周边区域... 相似文献
9.
《南方农业》2017,(22)
基于农业生产中翻耕、灌溉、化肥、农药、农膜和农用柴油等6个方面碳源,测算了河南省1993—2015年的农业碳排放量及排放强度。结果表明:河南省农业碳排放总量整体呈上升趋势,碳排放总量由1993年的347.09×10~4 t增加到2015年的874.59×10~4 t,年均增长4.32%,总体上呈"高速-中速-低速"三阶段演化特征。农业碳排放强度从1993年的每公顷484.11 kg增加到2015年的每公顷1 073.21 kg,年均增长3.72%。河南省农业碳排放总量与经济发展呈典型的倒"U"型曲线关系,且开始出现拐点,但不明显。灰色预测模型显示,2016—2020年,河南省农业碳排放总量将由1 002.85×10~4 t增加到1 184.01×10~4 t。建议河南省采取有效措施,实现农业碳减排。 相似文献
10.
[目的] 分析徐州市时空尺度下农业碳排放时空特征与脱钩效应,为江苏省徐州市及其周边资源型城市未来农业的绿色高质可持续发展以及农业经济的良性增长提供理论与数据参考。[方法] 采用排放系数法测算2000—2020年时空尺度下徐州市农业碳排放总量、强度和结构,而后基于Tapio脱钩模型分析其与农业经济发展间的脱钩关系。[结果] ①徐州市农业碳排放变化趋势总体呈“快速上升—波动上升—快速下降”3阶段,从2000年的1.61×106 t先增后减至2020年的1.69×106 t,形象地表现为“M”形。对农业碳排放贡献率大小依次是耕地利用(46.44%)、作物种植(31.90%)和牲畜养殖(21.66%),化肥是最主要碳源。②徐州市各区(县、市)农业碳排放量差异明显,经历了由升到降的长期演化进程,空间层面上总体呈现出“中部高,周边低”的分布格局,邳州市最为突出; ③徐州市农业碳排放与农业经济发展总体经历了“弱脱钩—强负脱钩—扩张负脱钩—强脱钩”的变化历程,且“十三五”以来主要表现为强脱钩。[结论] 徐州市农业碳排放随着低碳减排理念的不断深入而日趋合理,农业经济发展也取得了一定成效。 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.
Aleš Lebeda Ivana Doležalová Eva Křístková Barbora Mieslerová 《Genetic Resources and Crop Evolution》2001,48(2):153-164
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.
Kyle Devey Michael Mucalo Gordon Rajendram Joseph Lane 《Communications in Soil Science and Plant Analysis》2015,46(4):72-80
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.
Thomas Larsen Jesper Luxhøi Jakob Magid Lars Stoumann Jensen Paul Henning Krogh 《Biology and Fertility of Soils》2007,44(1):59-68
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.
《中国生态农业学报》2014,(6)
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.
《中国生态农业学报》2014,(7)
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.
I.L. Boyd 《Biological conservation》2010,143(7):1664-1674
“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.
Soil-profile distribution of primary and secondary plant-available nutrients under conventional and no tillage 总被引：1，自引：0，他引：1
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.
《中国生态农业学报》2014,(8)
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.
M.A. Callaham Jr. J.M. BlairT.C. Todd D.J. KitchenM.R. Whiles 《Soil biology & biochemistry》2003,35(8):1079-1093
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