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Diapause development in early and late emerging phenotypes of Delia floralis

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Insect Science 2014年第1期21卷 103-113页

作者： Tor J. Johansen Richard Meadow arctic agriculture and land use division Bioforsk - Norwegian Institute for Agricultural and Environmental Research Tromsm plant Health and Plant Protection division Bioforsk - Norwegian Institute for Agricultural and Environmental Research As Norway

The turnip fly, Delia floralis Fall6n （Diptera： Anthomyiidae） is an important insect pest of brassica vegetable crops in the holarctic region. Different populations have strongly varying temperature requirements for fly emergence, a challenge for accurate prediction of activity. This study focused on diapause development in one early and one late emerging phenotype. The physiological state after various treatments was deduced from emergence data. Our results showed a slow diapause progression at chilling conditions for both populations and diapause ended about 7 months after pupae were formed for the early population. For the late population held at 4℃ diapause did not end, no matter how long the duration of chilling. These pupae required a period with elevated temperatures above 6~C to continue development. At constant non-chilling conditions （18℃） from the time pupae were formed both populations completed diapause most rapidly. These results indicate that chilling delayed, rather than accelerated development and was not a prerequisite for diapause development. For post-diapause, results indicated a linear relationship between rate of development and temperature within the range of 6-18℃and a theoretical base temperature for development of about 2℃ for both populations. In conclusion, D. floralis pupae are in diapause throughout a long winter period, and delayed emergence of the late population appears to be caused by prolonged diapause regulated by a developmental temperature threshold. The study has added information on the biology of turnip fly populations, a prerequisite for improved pest control.

关键词： brassica chilling emergence hibernation quiescence

Managing agricultural phosphorus for water quality:Lessons from the USA and China

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Journal of Environmental Sciences 2014年第9期26卷 1770-1782页

作者： Andrew Sharpley Xiaoyan Wang Department of Crop Soil and Environmental SciencesDivision of AgricultureUniversity of ArkansasayettevilleARUSA College of Resources Environment & TourismCapital Normal University

The accelerated eutrophication of freshwaters and to a lesser extent some coastal waters is primarily driven by phosphorus （P） inputs. While efforts to identify and limit point source inputs of P to surface waters have seen some success, nonpoint sources remain difficult to identify, target, and remediate. As further improvements in wastewater treatment technologies becomes increasingly costly, attention has focused more on nonpoint source reduction, particularly the role of agriculture. This attention was heightened over the last 10 to 20 years by a number of highly visible cases of nutrient-related water quality degradation; including the Lake Taihu, Baltic Sea, Chesapeake Bay, and Gulf of Mexico. Thus, there has been a shift to targeted management of critical sources of P loss. In both the U.S. and China, there has been an intensification of agricultural production systems in certain areas concentrate large amounts of nutrients in excess of local crop and forage needs, which has increased the potential for P loss from these areas. To address this, innovative technologies are emerging that recycle water P back to land as fertilizer. For example, in the watershed of Lake Taihu, China one of the largest surface fresh waters for drinking water supply in China, local governments have encouraged innovation and various technical trials to harvest harmful algal blooms and use them for bio-gas, agricultural fertilizers, and biofuel production. In any country, however, the economics of remediation will remain a key limitation to substantial changes in agricultural production.

关键词： Beneficial management practicesEutrophicationFertilizer managementland useManure managementSoil conservationWatershed management

The use of woods-run chips in filter socks to control erosion and sedimentation during petroleum development in the Appalachian Basin

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International Journal of Sediment Research 2019年第6期34卷 608-615页

作者： Shawn T.Grushecky Louis M.McDonald Lawrence Osborn West Virginia University Davis College of Agriculture Natural Resources and Design School of Natural Resources Appalachian Hardwood Center at West Virginia University School of Natural Resources Energy Land Management 3. Division of Plant and Soil SciencesEnvironmental Soil Chemistry and Soil Fertility

Filter socks frequently are used for erosion and sediment perimeter control during oil and gas development activities in the Appalachian Basin of the United States.Regulations specify the use of composted wood material for sock construction.This specification,as opposed to non-composted or fresh wood chips(woods-run),has created inefficiencies during well site construction.Rather than use fresh wood chips created during site construction,composted chips must be procured and used as filter sock media for erosion and sedimentation mitigation.If woods-run chips could be used as filter sock media instead of composted chips,there could be a significant reduction in energy/capital costs,truck traffic,and disposal costs.The primary objective of this research project was to compare the effectiveness of woodsrun material versus traditionally composted wood chips in controlling sediment transport as well as other chemical and physical parameters in a laboratory setting.No significant differences in pH(5.96 versus 6.02) or conductivity(0.029 dS/m versus 0.035 dS/m) were found in sediment laden water filtered through woods-run versus composted chips,respectively.However,chip particle sizes were outside the allowable limits for composted sock media,and moisture content also was outside the specified limits for woods-run chips.Nitrate(NO) concentrations were significantly higher in woods-run,while phosphorus(P) and potassium(K) concentrations were greater in composted chips;however none of the N,P,or K concentrations were above the regulatory requirements.Finally,no difference in the filtering efficiency or time was found between woods-run and composted material.The laboratory results indicate that current regulations allowing the use of woods-run chips in all but the highest quality watersheds is justified.

关键词： BMP Filter socks Petroleum exploration Marcellus shale Wood chips

Irrigation system and land use effect on surface water quality in river, at lake Dianchi, Yunnan, China

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Journal of Environmental Sciences 2013年第6期25卷 1107-1116页

作者： Takashi Tanaka Takahiro Sato Kazuo Watanabe Ying Wang Dan Yang Hiromo Inoue Kunzhi Li Tatsuya Inamura Graduate School of agriculture Kyoto University Biotechnology Research Center Kunming University of Science and Technology Crop and Environmental Sciences division International Rice Research Institute Center for Southeast Asian Studies Kyoto University

The surface water samples were collected in river Dahe and its tributaries, which flow into severely eutrophic lake Dianchi, Yunnan Province, China, in order to elucidate factors controlling water quality fluctuations. The temporal and spatial distribution of water quality tendency was observed. The water quality of each river is dependent on the hydrology effect such water gate and circulating irrigation system. We must consider the hydrology effect to accurately understand water quality variations of river in this study field. In river without highly circulating irrigation system or water gate effect, the downstream nitrate nitrogen （NO3-N） concentration increase occurred in area dominated by open field cultivation, whereas the NO3-N concentration was constant or decreased in area dominated by greenhouse land use. This result suggests that greenhouse covers the soil from precipitation, and nitrate load of greenhouse could be less than that of open field cultivation while the rainfall event. In the upper reaches of river, where is dominated by open field cultivation, there were no sharp increase dissolved molybdate reactive phosphorus and total phosphorus concentration, but P load was accumulated in the lower reaches of river, whose predominant land use is greenhouse. Although the P sources is unclear in this study, greenhouse area may have potential of P loads due to its high P content in greenhouse soil. Considering hydrology effect is necessary to determine what the major factor is influencing the water quality variation, especially in area with highly complicated irrigation system in this studying site.

关键词： lake Dianchi eutrophication surface water quality land use plastic greenhouse circulating irrigation

Phylogenetic Diversity and Evaluation the Effectiveness of Indigenous <i>Bradyrhizobium</i>Strains for Myanmar Black Gram (<i>Vigna mungo</i>L. Hepper) Cultivars

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American Journal of Plant Sciences 2020年第2期11卷 285-306页

作者： Khin Myat Soe Aung Zaw Htwe Kyi Moe Tomomi Abiko Takeo Yamakawa Biofertilizer Laboratory Land Use Division Department of Agriculture Ministry of Agriculture Livestock and Irrigation Yangon Myanmar Department of Agronomy Yezin Agricultural University Yezin Myanmar Laboratory of Agroecology Department of Bioresource Sciences Faculty of Agriculture Kyushu University Harumachi Kasuya-Machi Kasuya-Gun Fukuoka Japan Laboratory of Plant Nutrition Department of Bioresource and Bioenvironmental Sciences Faculty of Agriculture Kyushu University Motooka Nishi-Ku Fukuoka Japan

Black gram (Vigna mungo L. Hepper) is one of the main leguminous crops that provide chief source of food. Several Bradyrhizobium species are able to induce effective nodules in black gram cultivars. In the present study, we characterized forty isolates of indigenous black gram bradyrhizobia from Myanmar based on the sequence analysis of the bacterial 16S rRNA gene. The sequence analysis confirmed that all isolates were categorized and identified as the genus Bradyrhizobium and they were conspecific with B. elkanii, B. sp., B. liaoningense, B. japonicum and B. yunamingense. Almost all the collected isolates from major black gram growing regions of Nyaunglebin Bago Regio, Chaungzon Mon State, Sittwe Rakhine State, Danubyu Ayeyarwady Region and Launglon Tanintharyi Region were identified as B. liaoningense. At Danubyu Ayeyarwady Region and Pyinmanar Nay Pyi Taw Region, most of the strains were identified as B. japonicum. On the other hand, more or less all the isolates from Launglon Tanintharyi Region and Hpa-an Kayin State were related to B. elkanii. However, all B. sp. strains were found in Salingyi Sagaing Region black gram growing region. This is the first report describing Bradyrhizobium strains that were isolated from soil samples of major black gram growing areas in Myanmar. Evaluation of the effectiveness of Myanmar Bradyrhizobim strains isolated from soil samples of major black gram growing areas of Myanmar for plant growth and nitrogen fixation was studied in pot experiments with completely randomized design and three replicates. The nodule dry weight, shoot dry weight and acetylene reduction activity of the plant inoculated with Bradyrhizobium elkanii LauBG38 were significantly higher in ARA per plant, nodule and shoot dry weights than the other tested isolates in both Yezin-4 and Yezin-7 black gram varieties. We expect that Myanmar Bradyrhizobium elkanii LauBG38 will be able to use as Biofertilizer for black gram cultivars.

关键词： Black Gram Myanmar 16S rRNA Gene Bradyrhizobium Nitrogen Fixation

Calculation and Simulation of Evapotranspiration of Applied Water

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Journal of Integrative agriculture 2012年第3期11卷 489-501页

作者： Richard L Snyder Shu Geng Morteza Orang Sara Sarreshteh Department of land Air and Water Resources University of California Davis CA 95616 USA School of Environment and Energy Shenzhen Graduate School Peking University Shenzhen 518055 P.R.China Department of Plant Sciences University of California Davis CA 95616 USA California Department of Water Resources Division of Statewide Integrated Water Management Water Use and Efficiency SacramentoCA 94236 USA

The University of California, Davis and the California Department of Water Resources have developed a weather generator application program “SIMETAW” to simulate weather data from climatic records and to estimate reference evapotranspiration （ETo） and crop evapotranspiration （ETc） with the generated simulation data or with observed data. A database of default soil depth and water holding characteristics, effective crop rooting depths, and crop coefficient （Kc） values to convert ETo to ETc are input into the program. After calculating daily ETc, the input and derived data are used to determine effective rainfall and to generate hypothetical irrigation schedules to estimate the seasonal and annual evapotranspiration of applied water （ETaw）, where ETaw is the net amount of irrigation water needed to produce a crop. in this paper, we will discuss the simulation model and how it determines ETaw for use in water resources planning.

关键词： weather generator water balance crop water requirements water resource planning crop coefficient

Coordinated development of land multi-function space: An analytical framework for matching the supply of resources and environment with the use of land space for ecological protection, agricultural production and urban construction

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Journal of Geographical Sciences 2023年第2期33卷 311-339页

作者： QU Yanbo ZHANG Yanjun WANG Shilei SHANG Ran ZONG Haining ZHAN Lingyun School of Public Management Shandong University of Finance and EconomicsJinan 250014China School of Resources and Environmental Engineering Shandong Agriculture and Engineering UniversityJinan 250100China

Based on the carrying capacity of the resources and the environment,this article defines the connotation of the land multifunctional space(LMFS)from three aspects,ecological protection,agricultural production and urban construction,in the new era of land space planning system.Moreover,a framework is constructed for the coordinated development of the multi-functional oriented space to match the use of land space(ULS)with the supply of resources and environment(SRE).Based on this,the technology and methods of comprehensive evaluation,dominance recognition,and matching relationship division functions of the use of land space(FULS)and functions of the supply of resources and environment(FSRE)are discussed.The advantageous functions of the use of land space(AFULS)and advantageous functions of the supply of resources and environment(AFSRE)are also identified in the study area.A LMFS coordinated development system integrating“function position-comprehensive partition-regulation strategy”is proposed.Through the empirical study of Shandong province,we found that,first,the FULS of ecological protection space in the province is mainly found in high value areas,and the FSRE is mainly in low value areas,which has certain complementarity in the space.The FULS of agricultural production space is mainly observed in high value areas,the FSRE is mainly in middle value areas,and the spatial distribution is balanced and staggered.The FULS of the urban construction space and the FSRE are mainly in middle values areas,and the spatial distribution is basically similar.Second,the FULS in the study area is dominated by the single advantage of agricultural production and urban construction,while the FSRE has a relatively balanced distribution of the advantages of ecological protection,single agricultural production and compound advantages of agricultural production and urban construction,and urban construction and ecological protection.The matching between the two is mainly at high and middle levels.Specifically,70%of the province’s land

关键词： land space coordinated development dominance matching relationship ecological protection agricultural production urban construction Shandong province

阿姆哈拉北Wollo地区农地可持续利用中面临的挑战与策略

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中国水土保持 2002年第7期 9-9页

作者： Nurhussen Taha Head Rural land use Planning division Ministry of AgricultureAddis Ababa

Spatio-temporal characteristics of cultivated land fragmentation in different landform areas with a case study in Northeast China

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Ecosystem Health and Sustainability 2020年第1期6卷 581-591,580页

作者： Fengkui Qian Yanru Chi Rattan Lal Klaus Lorenz College of land and Environment Shenyang Agriculture UniversityShenyangPR China National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources ShenyangPR China Carbon Management and Sequestration Center School of Environment and Natural ResourcesThe Ohio State UniversityColumbusOHUSA

Assessing the temporal and spatial characteristics of cultivated land fragmentation is necessary to identify management practices that can reduce negative environmental effects.Thus,the purpose of this study was to use principal component analysis and spatial autocorrelation to analyze the dynamic characteristics of cultivated land fragmentation in different landform areas in Liaoning Province,China,in terms of time and space.An additional objective was to match the changes with the natural and social environment to support the sustainable development of fragmented cultivated land.The results indicated that the evolutionary trends of cultivated land fragmentation in the central plain area showed a weakening trend,contrary to those observed in the western hilly and eastern mountainous areas.Moreover,the spatial distribution characteristics of cultivated land fragmentation in the western hilly area were generally“external low,internal high,”primarily because of the edge density of cultivated land patches.The spatial distribution characteristics of cultivated land fragmentation in the central plain area were generally“external high,internal low,”primarily because of the number and division of cultivated land patches.The spatial distribution characteristics of cultivated land fragmentation in the eastern mountainous area were generally“south low,north high”because of the division of cultivated land patches.These results can provide guidelines for planners,managers,decision-makers and others to formulate regulatory policies,identify land remediation areas,and promote the sustainable development of cultivated land.

关键词： Cultivated land fragmentation spatiotemporal characteristics different landforms Northeast China