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1.
Strong and rapid greenhouse gas (GHG) emission reductions, far beyond those currently committed to, are required to meet the goals of the Paris Agreement. This allows no sector to maintain business as usual practices, while application of the precautionary principle requires avoiding a reliance on negative emission technologies. Animal to plant-sourced protein shifts offer substantial potential for GHG emission reductions. Unabated, the livestock sector could take between 37% and 49% of the GHG budget allowable under the 2°C and 1.5°C targets, respectively, by 2030. Inaction in the livestock sector would require substantial GHG reductions, far beyond what are planned or realistic, from other sectors. This outlook article outlines why animal to plant-sourced protein shifts should be taken up by the Conference of the Parties (COP), and how they could feature as part of countries’ mitigation commitments under their updated Nationally Determined Contributions (NDCs) to be adopted from 2020 onwards. The proposed framework includes an acknowledgment of ‘peak livestock’, followed by targets for large and rapid reductions in livestock numbers based on a combined ‘worst first’ and ‘best available food’ approach. Adequate support, including climate finance, is needed to facilitate countries in implementing animal to plant-sourced protein shifts.

Key policy insights

  • Given the livestock sector’s significant contribution to global GHG emissions and methane dominance, animal to plant protein shifts make a necessary contribution to meeting the Paris temperature goals and reducing warming in the short term, while providing a suite of co-benefits.

  • Without action, the livestock sector could take between 37% and 49% of the GHG budget allowable under the 2°C and 1.5°C targets, respectively, by 2030.

  • Failure to implement animal to plant protein shifts increases the risk of exceeding temperate goals; requires additional GHG reductions from other sectors; and increases reliance on negative emissions technologies.

  • COP 24 is an opportunity to bring animal to plant protein shifts to the climate mitigation table.

  • Revised NDCs from 2020 should include animal to plant protein shifts, starting with a declaration of ‘peak livestock’, followed by a ‘worst first’ replacement approach, guided by ‘best available food’.

  相似文献   
2.
Oxygenation of the ocean is presumed to be an important factor stimulating the evolution of multicellular animals. The appearance of the Ediacaran‐type biota (ca 575 Ma) was assigned to the aftermath of the Gaskiers glaciation (ca 580 Ma), when substantial oceanic oxygenation is believed to have started. However, several lines of evidence reveal that at least sponges evolved before this oxygenation. For understanding the first stage of animal evolution, we propose the hypothesis that Dissolved Organic Carbon (DOC) Stimulated the evolution for Animal Multicellularity (DOXAM). Recent geochemical studies of the Ediacaran sedimentary sequences have indicated that a substantial DOC mass was developed in the stratified ocean after the Marinoan glaciation (655–635 Ma), and this was supported by the inorganic and organic carbon isotope profiles of the Doushantuo Formation in South China. The DOC mass was an oxygen consumer in the water column; however, it could have provided a food source for filter‐feeding animals such as sponges and cnidarians, and established a primitive food‐web. Such an ecological structure is recognized in modern deep‐sea coral mounds. Results from the integrated ocean drilling program (IODP) Expedition 307 for a mound in northeastern Atlantic suggested that organic carbon suspended around the density boundary in the water column is the key feature to feed the heterotrophic deep‐sea coral community. Our hypothesis is consistent with the fact that the two most primitive animal phyla (Porifera and Cnidaria) are filter feeders. The evolution of filter feeding ecosystems removed the DOC mass and may have contributed to ocean oxygenation in the terminal Neoproterozoic when animal evolution passed into the second stage, with the appearance of bilaterians.  相似文献   
3.
甲维盐属高效半合成抗生素杀虫剂。在哈尔滨市典型黑土农田区,研究不同浓度甲维盐处理对土壤动物群落结构的影响。结果表明:甲维盐处理显著降低了土壤动物群落的个体密度和类群数量,且这种趋势随着甲维盐浓度的增加而增强;显著改变了群落的垂直分布格局,表聚性特征被削弱,使动物较多地聚集于5~15 cm土层;改变了群落多样性特征,其中螨类和跳虫对多样性的贡献相对较大;显著改变了表层土壤化学性质,但不同动物类群对土壤环境变化的响应规律不同,螨类和跳虫对甲维盐干扰具有较强的适应能力。甲维盐处理可以显著改变黑土区农田土壤动物群落结构,浓度是影响该过程的重要因素,施用杀虫剂时需慎重评价其生态后果。  相似文献   
4.
Environmental degradation resulting from current climate changes, including prolonged drought, land degradation, desertification, and loss of biodiversity, is presenting enormous challenges to achieve ...  相似文献   
5.
Abundant perfectly-preserved phosphatic microspherules have been discovered across the Frasnian-Famennian(F-F)transition from the Yangdi section in Guilin,Guangxi,South China.They are mostly spherical or elliptical in shape and about 150μm in diameter with smooth exterior surfaces.Each microspherule consistently possesses a small dimple on the surface.The internal texture of microspherules consists of concentric light-colored apatite and dark-colored organic matter bands alternating around a central core.Conodonts have also been found preserved together with phosphatic microspherules in the same horizon,and the abundance of the former is obviously higher than that of the latter.Laser Raman spectral studies show close similarities in spectral patterns between the outer shells of phosphatic microspherules and the blade of the conodont genus Palmatolepis sp.,as well as between the microspherule nucleus and the platform of the same conodont genus.Furthermore,the statistical results and geochemical data demonstrate that the elevated abundance of phosphatic microspherules roughly coincides with the blooms of bacteria and algae,but is later than the sharp increase of oceanic nutrients.The phosphatic microspherules are interpreted here to be the‘otoliths’secreted by conodont animals based on the compositional similarities between phosphatic microspherules and conodonts and their interrelated abundances.In addition,an analogous study reveals morphological and textural similarities between fish otoliths and phosphatic microspherules.The formation of phosphatic microspherules is probably related to seawater eutrophication.We speculate that the explosive growth of bacteria and algae is probably caused by the enrichment of nutrients that is most likely associated with the increase of terrestrial inputs,submarine hydrothermal activities or the upwelling anoxic bottom waters in the late Devonian,which would stimulate the conodont animals to secrete phosphatic microspherules—the‘otoliths’of conodont animals.This study reveals the coupling relationship between organisms and environments from the perspective of phosphatic microspherules and provides new evidence for the cause of faunal crisis during the Late Devonian F-F transition.  相似文献   
6.
应用ESDA并结合标准差指数(S)、变异系数(V)等方法,从空间相关的视角分析新疆各县市农林牧渔业人均产值的空间差异。结果显示:以农林牧渔业人均产值来计算的新疆县域间的农林牧渔业人均产值呈现北疆高于东疆、南疆的空间差异。2003-2012年间:新疆县域农林牧渔业人均产值的空间自相关测度Moran's I呈曲线性增减态势,表明农林牧渔业人均产值的空间集聚性呈曲线性波动,但农林牧渔业人均产值的年增长率逐年上升。从局部自相关分析来看,区域间呈现两个极端化较为明显,说明新疆农林牧渔业人均产值在空间分布上具有不均衡性。  相似文献   
7.
南岭  董治宝  肖锋军 《中国沙漠》2017,37(6):1079-1084
粉尘释放是风蚀造成危害的一个重要过程。以农牧交错带沙区和非沙区农田土壤为研究对象,利用室内风洞模拟实验,实时监测了风蚀过程中释放的PM10,分析了PM10的动态变化特征,以深入认识土壤风蚀粉尘释放机理。结果表明:非沙区农田土壤风蚀强度远低于沙区农田,与风速呈指数函数关系;非沙区农田的土壤粉尘释放在不同风速下均以气流直接抬升模式为主,平均PM10通量与风速呈线性函数关系,最大PM10通量与风速呈幂函数关系;沙区农田的土壤粉尘释放在风速增大到一定程度后呈气流直接抬升和砂粒跃移冲击复合模式,最大PM10通量增加不明显,但平均PM10通量明显高于非沙区农田;对于沙区和非沙区农田而言,平均PM10通量与风蚀速率呈对数函数关系。  相似文献   
8.
目的:应用双源CT探讨新西兰兔耳缘静脉注入明胶海绵制造急性肺动脉栓塞(PE)模型的可行性。方法:新西兰兔24只随机分为实验组(n=22只,按栓塞后检查时间分为2h、1d、3d和7d组)与对照组(n=2只)。实验组22只采用经耳缘静脉快速注射明胶海绵栓子制成急性PE模型,栓塞前后均行CTPA及肺灌注检查,检查结束后全部处死。对照组2只新西兰兔经耳缘静脉注入等渗盐水后立即处死。全部行病理检查。结果:22只实验组新西兰兔制模成功20只,其中有2只分别因为栓塞过量和麻醉过量而未取得数据,模型制备成功率为90%。以肺叶为单位,在CT图像上分析100个肺叶影像表现,可见栓塞后2h组对应的肺叶纹理稀疏12叶;1d及3d组对应肺叶呈磨玻璃改变22叶;7d组对应肺叶实变3叶。DEPI均呈现低灌注。病理检查发现:2h组相应肺组织呈鲜红色,未见结构破坏及肺泡渗出;1d组对应肺组织呈水肿、淤血、出血及炎细胞浸润改变;3d组部分肺组织轻度梗死,对应肺组织呈深红色,肺泡间隔增宽,大量炎细胞浸润;7d组肺泡腔被渗出物填充,对应肺组织呈暗红色,实变坏死。实验组共发现3只新西兰兔肺动脉管腔内含明胶海绵。结论:经新西兰兔耳缘静脉注射明胶海绵制作急性肺栓塞动物模型操作简单,成本低廉,成功率较高,是肺栓塞影像学研究较容易制作的实验模型。   相似文献   
9.
10.
两个龙须菜新品系经济性状及琼胶特性的初步研究   总被引:1,自引:0,他引:1  
2008年2~5月在广东省南澳县深澳海区对选育的龙须菜新品系07-1,07-2和对照组福建宁德栽培的981品系进行海上栽培比较试验,测定了3个品系的藻体日平均生长速率,试验了敌害生物(藻钩虾和团水虱)对3个品系的影响,比较了琼胶特性.结果显示,在水温11~20 ℃,盐度32.4~32.8的条件下,品系07-1,07-2的藻体日平均生长速率分别为3.8%/d和4.1%/d,宁德栽培品系的藻体日平均生长速率为3.2%/d.品系07-1,07-2的生长适应水温下限为16 ℃,比宁德栽培品系降低了2 ℃.与宁德栽培的981品系相比较,选育的龙须菜品系07-1,07-2对藻钩虾和团水虱有较强的耐受能力.品系07-1,07-2的琼胶含量比福建宁德栽培的981品系分别提高10.0%和14.4%,凝胶强度也分别提高了5.46%和14.5%,表明2个新品系具有潜在的推广应用价值.  相似文献   
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