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1.
There are few reliable data sets to inspire confidence in policymakers that soil organic carbon (SOC) can be measured on farms. We worked with farmers in the Tamar Valley region of southwest England to select sampling sites under similar conditions (soil type, aspect and slope) and management types. Topsoils (2–15 cm) were sampled in autumn 2015, and percentage soil organic matter (%SOM) was determined by loss on ignition and used to calculate %SOC. We also used the stability of macroaggregates in cold water (WSA) (‘soil slaking’) as a measure of ‘soil health’ and investigated its relationship with SOC in the clay‐rich soils. %SOM was significantly different between management types in the order woodland (11.1%) = permanent pasture (9.5%) > ley‐arable rotation (7.7%) = arable (7.3%). This related directly to SOC stocks that were larger in fields under permanent pasture and woodland compared with those under arable or ley‐arable rotation whether corrected for clay content (F = 8.500, p < .0001) or not (F = 8.516, p < .0001). WSA scores were strongly correlated with SOC content whether corrected for clay content (SOCadj R2 = .571, p < .0001) or not (SOCunadj R2 = 0.490, p = .002). Time since tillage controlled SOC stocks and WSA scores, accounting for 75.5% and 51.3% of the total variation, respectively. We conclude that (1) SOC can be reliably measured in farmed soils using accepted protocols and related to land management and (2) WSA scores can be rapidly measured in clay soils and related to SOC stocks and soil management.  相似文献   
2.
Rising temperatures caused by climate change are likely to affect cool‐water and warm‐water fishes differently. Yet, forecasts of anticipated temperature effects on fishes of different thermal guilds are lacking, especially in freshwater ecosystems. Towards this end, we used spatially explicit, growth rate potential (GRP) models to project changes in seasonal habitat quality for a warm‐water piscivore (largemouth bass Micropterus salmoides), a cool‐water piscivore (walleye Sander vitreus) and a hybrid piscivore (saugeye S. vitreus × S. canadensis) in two Midwestern reservoirs. We assessed habitat quality for two periods (early and middle 21st century) under two realistic greenhouse gas emission scenarios (a mid‐century emissions peak and a rapid continuous increase in emissions). Largemouth bass were projected to experience enhanced or slightly reduced habitat during all seasons, and throughout the mid‐21st century. By contrast, walleye habitat was projected to decline with anticipated warming, except during the spring in the smaller of our two study reservoirs and during the fall in the larger of our two study reservoirs. Saugeye habitat was projected to either increase modestly or decline slightly during the spring and fall and declines in habitat quality and quantity that were smaller than those for walleye were identified during summer. Collectively, our findings indicate that climate warming will differentially alter habitat suitability for reservoir piscivores, favouring warm‐water species over cool‐water species. We expect these changes in habitat quality to impact the dynamics of reservoir fish populations to varying degrees necessitating the consideration of climate when making future management decisions.  相似文献   
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A 7-month-old, intact male, mixed breed dog with bilateral inguinal hernias underwent general anesthesia for laparoscopic bilateral inguinal herniorrhaphy via a 3-port approach. A 3-dimensional laparoscopic system was used to perform the procedure immediately following prescrotal open castration. Intracorporeal suturing with polypropylene was performed, and 2 cruciate sutures were placed to close each inguinal ring. The caudal aspect of each inguinal ring was left slightly open so as not to disrupt the passage or patency of vessels and nerves. No intra- or post-operative complications occurred. One year after surgery, the dog has no evidence of recurrence of the inguinal hernias.Key clinical message:This case report demonstrates a novel minimally invasive approach to inguinal herniorrhaphy in a dog with no reported complications and a good long-term outcome. Intracorporeally sutured inguinal herniorrhaphy is feasible in dogs with good results, although additional cases are needed to gain experience with this technique in dogs with varying presentations of inguinal hernias.  相似文献   
4.
林啸 《安徽农业科学》2021,49(18):73-78
在闽西山区九龙江流域,以河岸缓冲带植物杂交狼尾草、红花檵木、红叶石楠为研究对象,分析茎、叶中碳、氮、磷的生态化学计量特征,以及植物对碳、氮、磷的累积量,对九龙江缓冲带不同植物碳氮磷化学计量特征进行研究.结果表明,杂交狼尾草、红花檵木、红叶石楠,单位面积地上部分总生物量分别为47.12、4.32、25.85 kg/m2,年际间增加量分别为58.21、2.59、6.02 kg/m2;不同植物及各营养器官C、N、P含量分布,均表现为碳含量>氮含量>磷含量,杂交狼尾草磷含量显著高于其余2种植物(P<0.05);杂交狼尾草叶片的C:N、C:P显著低于红花檵木和红叶石楠(P<0.05),杂交狼尾草对氮磷的利用效率不占优势;杂交狼尾草的碳氮磷累积增长率分别为201.88%、351.53%和569.45%,高于红花檵木与红叶石楠.该研究结果可为九龙江流域的面源污染治理以及河岸植物缓冲带的构建提供理论依据和实践参考.  相似文献   
5.
综述皱木耳Auricularia delicata新品种"鹿肚耳"的形态特征和食用特点,测定其与黑木耳、毛木耳、毛木耳白色变种"玉木耳"人工栽培子实体的基本营养成分、矿质元素含量和氨基酸组成,评价其营养价值。结果表明:鹿肚耳热量235 kJ/100g、蛋白质7.21 g/100g、脂肪1.5 g/100g、碳水化合物48.4 g/100g、总膳食纤维29.3g/100g,含有5种常量元素、5种必需微量元素,其中,硒元素含量是黑木耳的4.6倍;含有人体所需的8种必需氨基酸,氨基酸化学评分(CS)和氨基酸评分(ASS)分别为12和18.86,色氨酸为其限制性氨基酸;蛋白质综合评价低于其他3种木耳。  相似文献   
6.
Abstract

A study was carried out in sandy clay loam textured soil of Mymensingh, Bangladesh to evaluate weed control efficiency of pre-emergence herbicide pyrazosulfuron-ethyl either alone or in sequential application with post-emergence herbicide in transplanted rainy season rice under non-puddled strip-tilled (NPST) field condition and also to examine the residual effect of those herbicides on germination and growth of the subsequently grown wheat crop. Five treatment combinations of pyrazosulfuron-ethyl were tested against one weedy check and one weed-free check. The study revealed that NPST rice field was mostly infested by grass and sedge weeds and herbicide treatments offered a wide range of control (above 50% to 95%) on all types of weeds. Application of pyrazosulfuron-ethyl followed by (fb) orthosulfamuron fb butachlor plus propanil provided the most effective and economic weed control over two years of the study. Moreover, micro-plot bioassay study claimed germination and growth of subsequently grown wheat were not adversely affected by herbicides that were applied in rice. Therefore, application of pyrazosulfuron-ethyl followed by post-emergence herbicide could be effective and economic to control weeds in NPST rice under rice-wheat system, but proper rate and time of application should strictly be followed.  相似文献   
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自从2018年8月我国报告首例非洲猪瘟疫情以来,经过3年多的艰难探索,我们面对非洲猪瘟疫情从最初的恐惧和束手无策,到现在的精准清除和“与狼共舞”,疫情防控从被动应对进入到常态化管理和无疫小区建设阶段;非洲猪瘟可防可控的预测得到了实践证明。但是由于我国幅员辽阔,养猪模式多样,疫情防控水平参差不齐;非洲猪瘟疫情零星散发的风险持续存在。下面就我们的观察和调查,对近年来非洲猪瘟防控上的一些经验和误区进行简要分析。  相似文献   
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