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1.
Gangwar  R. K.  Makádi  M.  Demeter  I.  Táncsics  A.  Cserháti  M.  Várbíró  G.  Singh  J.  Csorba  Á.  Fuchs  M.  Michéli  E.  Szegi  T. 《Eurasian Soil Science》2021,54(7):1007-1018
Eurasian Soil Science - This study was conducted with the aim to assess the effect of land use on chemical properties (organic carbon; pH; electrical conductivity; available P, K, Ca, Mg, Na),...  相似文献   
2.
Precision Agriculture - Farm management information system (FMIS) is an important element of precision agriculture to support the decision making process in the agricultural business. Developing...  相似文献   
3.
  1. Marine aquaculture, and its fast-growing development, has the potential for wider environmental, ecosystem, and biodiversity impacts. This study assesses the impact of fish farming on a bottlenose dolphin (Tursiops truncatus) population within the Gulf of Ambracia (western Greece) between 2007 and 2018. Two different study areas were defined in order to investigate differences on occurrence, abundance, behaviour, and seasonal fluctuations between them: a ‘control area’, in the north-western side of the Gulf; and a ‘fish farm area’, in the south west, where the highest density of fish farm cages is found.
  2. A total of 169 daily surveys were dedicated to the control area and 74 days were dedicated to the fish farm area, yielding 104 and 37 sightings, respectively. Both the probability of detecting dolphins (U = 6,763.000, P = 0.002) and the group sizes (U = 578.000, P < 0.001) were smaller around fish farms.
  3. Seasonality analyses were restricted to 2007–2008, as this was the period with year-round effort. Results revealed that dolphins were more frequently seen around fish farms in the winter (Kruskal–Wallis test, P = 0.036).
  4. From the 40 identified individuals that were re-sighted at least 10 times during the study period, 21 used the fish farm area less than expected according to sampling effort, and 10 of them were never observed in that area (binomial test, P < 0.05).
  5. The results revealed an impact of fish farms on the distribution of bottlenose dolphins in the Gulf of Ambracia. This information should be taken into consideration when defining ecosystem-based management measures within the management plan, which is currently in preparation for this Natura 2000 site.
  相似文献   
4.
Journal of Soils and Sediments - Phosphorus (P) is often the main limiting factor for plant growth in highly weathered tropical soils. Phosphate use efficiency and crop yields could be increased in...  相似文献   
5.
  1. Taxonomic and functional trajectories of benthic assemblages were studied in shallow soft-bottom sediments in the bay of Saint-Brieuc (Western English Channel). Changes were assessed at different spatial and temporal scales using a macrobenthic dataset based on 38 stations sampled in 1987 and 2019, coupled with data from one station sampled annually between 2005 and 2019 as part of the European Water Framework Directive monitoring programme.
  2. Taxonomic trajectories indicated 1) changes in the structure and distribution of benthic assemblages, 2) an homogenization of the assemblages, and 3) significant functional shifts.
  3. Fishing activities and nutrient enrichment are probably strong drivers of the observed changes, as suggested by the higher mortality rate of fragile, flexible, tubiculous and burrowing species, and the increase in the abundance of opportunistic species in the assemblages. Certain populations of macroinvertebrates seem jointly controlled by climate change and by the aforementioned local factors of disturbance.
  4. The Community Trajectory Analysis framework appears as a new and interesting method to track ecological changes in marine ecosystems by measuring change with respect to a baseline state, to help define ecological recovery (station returning to the initial ecological state) and departure (station presenting increased changes over time), and to analyse trajectory similarity.
  5. According to the degradation of habitat over time, we identify the need for the implementation of knowledge-based conservation strategies, especially within Natura 2000 sites.
  相似文献   
6.
Dabrin  A.  Bégorre  C.  Bretier  M.  Dugué  V.  Masson  M.  Le Bescond  C.  Le Coz  J.  Coquery  M. 《Journal of Soils and Sediments》2021,21(2):1256-1274
Journal of Soils and Sediments - Suspended particulate matter (SPM) transport through rivers is a major vector of nutrients and pollutants to continental shelf areas. To develop efficient sediment...  相似文献   
7.
Bouteldja  M.  Malek  I.  Posta  K.  Kampfl  G.  Fóti  S.  Pintér  K.  Nagy  Z.  Balogh  J. 《Eurasian Soil Science》2021,54(8):1183-1195
Eurasian Soil Science - There is a need for long-term data on N2O emission in Central Europe to provide a thorough understanding of the variability of the emission processes as affected by...  相似文献   
8.
【目的】株高和穗部性状是影响谷子产量的关键性状。探究谷子株高及穗部性状表型变异的遗传规律,为相关性状的遗传改良与基因定位提供参考依据。【方法】以谷子优质品种豫谷18为共同父本,分别与黄软谷和红酒谷杂交,构建2个分别包含250个家系的重组自交系F7群体(YYRIL和YRRIL)。采用主基因+多基因混合遗传模型,对YYRIL和YRRIL群体在2个环境下的株高、穗长、穗下节间长、穗码数、穗粒重等5个农艺性状的表型数据进行遗传分析。【结果】5个性状在所有环境中均表现连续变异且存在超亲分离现象,峰度和偏度绝对值小于1,近似正态分布,呈现数量性状的典型遗传特点。性状间相关性分析表明株高与穗长、穗下节间长在所有环境中均呈极显著正相关,穗码数与穗粒重呈极显著正相关。遗传模型分析显示YYRIL和YRRIL群体株高的最适遗传模型分别为PG-AI和PG-A多基因模型,多基因遗传率分别为95.15%和91.27%。2个群体穗码数的最适模型均为PG-AI,多基因遗传率为70.07%—71.58%。穗下节间长在2个群体的最适遗传模型分别为4MG-CEA和3MG-CEA,均为等加性主基因模型。穗下节间长在YYRIL群体的主基因遗传率为9.69%,4对主基因加性效应值相等,均为-0.34,具有负向效应;穗下节间长在YRRIL群体的主基因遗传率为45.78%,3对主基因加性效应值相等,均为1.17,具有正向效应。穗长在YYRIL群体的最适模型为MX2-ED-A,即2对显性上位主基因+加性多基因模型,主基因遗传率为43.56%,多基因遗传率为50.56%。控制穗长的2对主基因加性效应值分别为-1.21、1.68,多基因加性效应较小,为-0.0017;穗长在YRRIL群体的最适模型为MX2-AE-A,即2对累加作用主基因,加性多基因混合遗传模型;穗长的主基因遗传率为46.40%,多基因遗传率为46.91%。控制穗长的第1对主基因加性效应值为1.53,具有正向效应,第1对主基因加性×第2对主基因加性上位性互作效应值是0.60,多基因加性效应值为-0.47,表现为较低的负向遗传效应。穗粒重在YYRIL群体的最适遗传模型为MX2-ED-A;符合2对显性上位主基因+加性多基因模型,主基因遗传率为69.09%,多基因遗传率为12.08%;控制穗粒重的2对主基因加性效应值分别为0.58、5.82,以第2对主基因的加性效应为主,多基因加性效应值为-3.81。穗粒重在YRRIL群体的最适遗传模型为3MG-PEA,即3对部分等加性主基因遗传模型;穗粒重的主基因遗传率为81.10%,3对主基因加性效应值分别为-2.68、-2.68和2.66,前2对主基因的加性效应值相同,且均为负向效应。【结论】谷子株高、穗码数的最适遗传模型相似,均服从多基因遗传,遗传率较高,受环境影响较小;穗下节间长的遗传受主基因控制,主基因遗传率偏低,受环境影响较大,在栽培中应充分考虑环境因素;穗长遗传受主基因和多基因共同控制;穗粒重在2个群体均服从主基因遗传,主基因遗传率较高,可能存在主效QTL。  相似文献   
9.
正Mating disruption(MD) is an effective environmentallyfriendly control method against the striped rice stem borer(RSB), Chilo suppressalis(Lepidoptera: Crambidae). In this study, the current MD dispensers release the pheromone exponentially, with higher initial release rates that decrease throughout the time. To adjust the timing of dispensers' deployment and evaluate the importance of controlling the early first or the second male flight,  相似文献   
10.
Li  Shu  Jaworski  Coline C.  Hatt  Séverin  Zhang  Fan  Desneux  Nicolas  Wang  Su 《Journal of pest science》2021,94(3):679-689
Journal of Pest Science - Flower strips can play an important role in agro-ecosystems by supporting populations of pests’ natural enemies, thereby enhancing biological control. However, few...  相似文献   
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