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Impacts of climate variability and extremes on global net primary production in the first decade of the 21st century

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Journal of Geographical Sciences 2015年第9期25卷 1027-1044页

作者： PAN Shufen TIAN Hanqin DANGAL Shree R.S. OUYANG Zhiyun LU Chaoqun YANG Jia TAO Bo REN Wei banger kamaljit YANG Qichun ZHANG Bowen International Center for Climate and Global Change Research School of Forestry and Wildlife Sciences Auburn University AL-36849 USA State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences CAS Beijing 100085 China

A wide variety of studies have estimated the magnitude of global terrestrial net primary production （NPP）, but its variations, both spatially and temporally, still remain uncertain. By using an improved process-based terrestrial ecosystem model （DLEM, Dynamic Land Ecosystem Model）, we provide an estimate of global terrestrial NPP induced by multiple environmental factors and examine the response of terrestrial NPP to climate variability at biome and global levels and along latitudes throughout the first decade of the 21st century. The model simulation estimates an average global terrestrial NPP of 54.6 Pg C yr-1 during 2000-2009, varying from 52.8 Pg C yr-1 in the dry year of 2002 to 56.4 Pg C yr-1 in the wet year of 2008. In wet years, a large increase in terrestrial NPP compared to the decadal mean was prevalent in Amazonia, Africa and Australia. In dry years, however, we found a 3.2% reduction in global terrestrial NPP compared to the decadal mean, primarily due to limited moisture supply in tropical regions. At a global level, precipitation explained approximately 63% of the variation in terrestrial NPP, while the rest was attributed to changes in temperature and other environmental factors. Precipitation was the major factor determining inter-annual variation in terrestrial NPP in low-latitude regions. However, in midand high-latitude regions, temperature variability largely controlled the magnitude of terrestrial NPP. Our results imply that pro- jected climate warming and increasing climate extreme events would alter the magnitude and spatiotemporal patterns of global terrestrial NPP.

关键词： climate variability climate extreme drought global terrestrial ecosystem net primary production（NPP）

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Maximizing Resource Efficiency in Cloud Data Centers through Knowledge-Based Flower Pollination Algorithm (KB-FPA)

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Computers, Materials & Continua 2024年第6期79卷 3757-3782页

作者： Nidhika Chauhan Navneet Kaur kamaljit Singh Saini Sahil Verma Kavita Ruba Abu Khurma Pedro A.Castillo University Institute of Computing Department Chandigarh UniversityPunjab140413India Department of Computer Science and Engineering Chandigarh UniversityPunjab140413India Universidade Federal do Piauí TeresinaPiauí64049-550Brazil MEU Research Unit Faculty of Information TechnologyMiddle East UniversityAmman11831Jordan Applied Science Research Center Applied Science Private UniversityAmman11931Jordan Department of Computer Engineering Automatics and RoboticsUniversity of GranadaGranada18071Spain

Cloud computing is a dynamic and rapidly evolving field,where the demand for resources fluctuates continuously.This paper delves into the imperative need for adaptability in the allocation of resources to applications and services within cloud computing environments.The motivation stems from the pressing issue of accommodating fluctuating levels of user demand efficiently.By adhering to the proposed resource allocation method,we aim to achieve a substantial reduction in energy consumption.This reduction hinges on the precise and efficient allocation of resources to the tasks that require those most,aligning with the broader goal of sustainable and eco-friendly cloud computing systems.To enhance the resource allocation process,we introduce a novel knowledge-based optimization algorithm.In this study,we rigorously evaluate its efficacy by comparing it to existing algorithms,including the Flower Pollination Algorithm(FPA),Spark Lion Whale Optimization(SLWO),and Firefly Algo-rithm.Our findings reveal that our proposed algorithm,Knowledge Based Flower Pollination Algorithm(KB-FPA),consistently outperforms these conventional methods in both resource allocation efficiency and energy consumption reduction.This paper underscores the profound significance of resource allocation in the realm of cloud computing.By addressing the critical issue of adaptability and energy efficiency,it lays the groundwork for a more sustainable future in cloud computing systems.Our contribution to the field lies in the introduction of a new resource allocation strategy,offering the potential for significantly improved efficiency and sustainability within cloud computing infrastructures.

关键词： Cloud computing resource allocation energy consumption optimization algorithm flower pollination algorithm

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Global pattern and change of cropland soil organic carbon during 1901-2010: Roles of climate, atmospheric chemistry, land use and management

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Geography and Sustainability 2020年第1期1卷 59-69页

作者： Wei Ren kamaljit banger Bo Tao Jia Yang Yawen Huang Hanqin Tian Department of Plant&Soil Sciences College of AgricultureFood and EnvironmentUniversity of KentuckyLexingtonKY 40506USA Plant Agriculture-University of Guelph Ontario N1G 2W1Canada Department of Forestry Mississippi State UniversityMississippi StateMS 39762USA International Center for Climate and Global Change Research and School of Forestry and Wildlife Sciences Auburn UniversityAuburnAL 36849USA

Soil organic carbon(SOC)in croplands is a key property of soil quality for ensuring food security and agricultural sustainability,and also plays a central role in the global carbon(C)budget.When managed sustainably,soils may play a critical role in mitigating climate change by sequestering C and decreasing greenhouse gas emissions into the atmosphere.However,the magnitude and spatio-temporal patterns of global cropland SOC are far from well constrained due to high land surface heterogeneity,complicated mechanisms,and multiple influencing factors.Here,we use a process-based agroecosystem model(DLEM-Ag)in combination with diverse spatially-explicit gridded environmental data to quantify the long-term trend of SOC storage in global cropland area during 1901-2010 and identify the relative impacts of climate change,elevated CO2,nitrogen deposition,land cover change,and land management practices such as nitrogen fertilizer use and irrigation.Model results show that the total SOC and SOC density in the 2000s increased by 125%and 48.8%,respectively,compared to the early 20th century.This SOC increase was primarily attributed to cropland expansion and nitrogen fertilizer use.Factorial analysis suggests that climate change reduced approximately 3.2%(or 2,166 Tg C)of the total SOC over the past 110 years.Our results indicate that croplands have a large potential to sequester C through implementing better land use management practices,which may partially offset SOC loss caused by climate change.

关键词： Global cropland Soil organic carbon Climate change Land management Process-based modeling

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Responses of global terrestrial water use efficiency to climate change and rising atmospheric CO_(2)concentration in the twenty-first century

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International Journal of Digital Earth 2018年第6期11卷 558-582页

作者： Shufen Pan Guangsheng Chen Wei Ren Shree R.S.Dangal kamaljit banger Jia Yang Bo Tao Hanqin Tian International Center for Climate and Global Change Research School of Forestry and Wildlife SciencesAuburn UniversityAuburnALUSA State Key Laboratory of Urban and Regional Ecology Research Center for EcoEnvironmental SciencesChinese Academy of SciencesBeijingPeople’s Republic of China Department of Plant and Soil Sciences College of AgricultureFood and EnvironmentUniversity of KentuckyLexingtonKYUSA

Terrestrial ecosystems play a significant role in global carbon and water cycles because of the substantial amount of carbon assimilated through net primary production and large amount of water loss through evapotranspiration(ET).Using a process-based ecosystem model,we investigate the potential effects of climate change and rising atmospheric CO_(2)concentration on global terrestrial ecosystem water use efficiency(WUE)during the twenty-first century.Future climate change would reduce global WUE by 16.3%under high-emission climate change scenario(A2)and 2.2%under low-emission climate scenario(B1)during 2010–2099.However,the combination of rising atmospheric CO_(2)concentration and climate change would increase global WUE by 7.9%and 9.4%under A2 and B1 climate scenarios,respectively.This suggests that rising atmospheric CO_(2)concentration could ameliorate climate change-induced WUE decline.Future WUE would increase significantly at the high-latitude regions but decrease at the low-latitude regions under combined changes in climate and atmospheric CO_(2).The largest increase of WUE would occur in tundra and boreal needleleaf deciduous forest under the combined A2 climate and atmospheric CO_(2)scenario.More accurate prediction of WUE requires deeper understanding on the responses of ET to rising atmospheric CO_(2)concentrations and its interactions with climate.

关键词： Climate change evapotranspiration net primary productivity water use efficiency

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A Fuzzy Approach for an IoT-Based Automated Employee Performance Appraisal

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Computers, Materials & Continua 2017年第1期53卷 23-36页

作者： Jaideep Kaur kamaljit Kaur Guru Nanak Dev University AmritsarPunjab India

The ubiquitous Internet of Things (IoT) through RFIDs, GPS, NFC and otherwireless devices is capable of sensing the activities being carried around Industrialenvironment so as to automate industrial processes. In almost every industry, employeeperformance appraisal is done manually which may lead to favoritisms. This paperproposes a framework to perform automatic employee performance appraisal based ondata sensed from IoT. The framework classifies raw IoT data into three activities (Positive,Negative, Neutral), co-locates employee and activity in order to calculate employeeimplication and then performs cognitive decision making using fuzzy logic. From theexperiments carried out it is observed that automatic system has improved performance ofemployees. Also, the impact of the proposed system leads to motivation among employees.The simulation results show how fuzzy approach can be exploited to reward or penalizeemployees based on their performance.

关键词： Employee Performance appraisal, fuzzy logic internet of things (IoT) cognitive decision making

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Global methane and nitrous oxide emissions from terrestrial ecosystems due to multiple environmental changes

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Ecosystem Health and Sustainability 2015年第1期1卷 23-43页

作者： Hanqin Tian Guangsheng Chen Chaoqun Lu Xiaofeng Xu Wei Ren Bowen Zhang kamaljit banger Bo Tao Shufen Pan Mingliang Liu Chi Zhang Lori Bruhwiler Steven Wofsy International Center for Climate and Global Change Research School of Forestry and Wildlife SciencesAuburn UniversityAuburnAlabama 36849 USA Environmental Sciences Division Oak Ridge National LaboratoryOak RidgeTennessee 37831 USA Department of Biological Sciences University of Texas at El Paso500 West University AvenueEl PasoTexas 79902 USA Department of Civil and Environmental Engineering Washington State UniversityPullmanWashington 99164 USA Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011 China NOAA Earth System Research Laboratory 325 BroadwayBoulderColorado 80305-3337 USA Department of Earth and Planetary Science Harvard University29 Oxford StreetCambridgeMassachusetts 02138 USA

Greenhouse gas(GHG)-induced climate change is among the most pressing sustainability challenges facing humanity today,posing serious risks for ecosystem health.Methane(CH_(4))and nitrous oxide(N_(2)O)are the two most important GHGs after carbon dioxide(CO_(2)),but their regional and global budgets are not well known.In this study,we applied a process-based coupled biogeochemical model to concurrently estimate the magnitude and spatial and temporal patterns of CH_(4)and N_(2)O fluxes as driven by multiple environmental changes,including climate variability,rising atmospheric CO_(2),increasing nitrogen deposition,tropospheric ozone pollution,land use change,and nitrogen fertilizer use.The estimated CH_(4)and N_(2)O emissions from global land ecosystems during 1981-2010 were 144.39±12.90 Tg C/yr(mean 62 SE;1 Tg=1012 g)and 12.52±0.74 Tg N/yr,respectively.Our simulations indicated a significant(P,0.01)annually increasing trend for CH_(4)(0.43±0.06 Tg C/yr)and N_(2)O(0.14±0.02 Tg N/yr)in the study period.CH_(4)and N_(2)O emissions increased significantly in most climatic zones and continents,especially in the tropical regions and Asia.The most rapid increase in CH_(4)emission was found in natural wetlands and rice fields due to increased rice cultivation area and climate warming.N_(2)O emission increased substantially in all the biome types and the largest increase occurred in upland crops due to increasing air temperature and nitrogen fertilizer use.Clearly,the three major GHGs(CH_(4),N_(2)O,and CO_(2))should be simultaneously considered when evaluating if a policy is effective to mitigate climate change.

关键词： coupled biogeochemical cycles global warming potential greenhouse gas methane nitrous oxide terrestrial ecosystem

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What Kind of Development We Want to Afford Sustainable Living?

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Journal of Environmental Science and Engineering(A) 2018年第1期7卷 34-48页

作者： kamaljit Kaur Sangha Darwin Centre for Bushfire Research Research Institute for the Environment and LivelihoodsCharles Darwin UniversityDarwin 0810Australia

The historical evidence is used to argue that the application of knowledge and modernization of the current economic and conservation approaches for directly relating to human dependence on nature are critical for advancing human well-being.Over the last^50 years,despite our sound understanding of various ecological impacts at local,regional and global scales,we have largely failed to prevent decline in the health of natural systems worldwide.Our current approaches continue to promote utilitarian economy,focusing on materials.This paper advocates a shift from the current paradigms of economics and resource use,by proposing an ethical approach both to nature and economics,towards holistic development.The approach is based on peoples’well-being.It outlines how by integrating ethics,economy and nature,and finding simple solutions within the reach of public,sustainable development can become achievable much more efficiently and quickly than following our current lengthy and complex processes.

关键词： Nature natural systems ecosystem services sustainable development economics human well-being

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Stem Reserve Mobilization and Sink Activity in Wheat under Drought Conditions

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American Journal of Plant Sciences 2011年第1期2卷 70-77页

作者： Anil K. Gupta kamaljit Kaur Narinder Kaur 不详

The effect of water deficit on stem reserve mobilization and sink activity in wheat (Triticum aestivum L.) cultivars, viz., C306 (drought tolerant) and PBW343 (drought sensitive) was studied. Drought was maintained in pot raised plants by withholding irrigation at 95 days after sowing (DAS), i.e. just five days before the initiation of anthesis. Drought induced a significant reduction in mean biomass of all the internodes of sensitive cultivar as compared to those of tolerant one. Mobilized dry matter and mobilization efficiency were observed to be higher in the internodes of tolerant cultivar, both under control and stress conditions, which resulted in enhanced translocation of stem reserves to the grains. Water soluble carbohydrates (WSC), which mainly occur as fructans, were observed to be higher in the internodes of tolerant cultivar than those of sensitive one. When drought was applied, fructans were mobilized more effectively from the internodes of tolerant cultivar. A significantly higher sucrose synthase activity in the grains of tolerant cultivar, under drought conditions, increased the sink strength by unloading the assimilates in the sink, thereby increasing further mobilization of assimilates to the grains. Grains of sensitive cultivar attained maturity much earlier as compared to the tolerant one, both under control and stress conditions. The longer duration of grain maturation in tolerant cultivar supported enhanced mobilization of stem reserves, thus restricting heavy decrease in grain yield, under stress conditions, as compared to the sensitive cultivar. It may, therefore, be concluded that certain characteristics viz., enhanced capability of fructan storage, higher mobilization efficiency, stronger sink activity and longer duration of grain maturation might help the drought tolerant cultivar in coping the stress

关键词： Acid Invertase Fructans Water Soluble Carbohydrate Sink Activity Stem Reserve Mobilization Sucrose Synthase Triticum Aestivum

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Impacts of Land Cover Change on Conservation, a Linkage of Spatial Analysis and Anthropogenic Activities in Tanzania

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Open Journal of Forestry 2018年第3期8卷 344-361页

作者： Herman N. Nyanda Juma J. Kegamba kamaljit K. Sangha Tanzania Wildlife Authority (TAWA) Morogoro Tanzania College of African Wildlife Management Mweka Moshi Kilimanjaro Tanzania Research Institute for the Environment and Livelihoods Charles Darwin University Darwin NT Australia

We used spatial analysis to assess the Land Use Land Cover (LULC) changes, and studied the impacts of LC changes on conservation of buffer zone of the Selous Game Reserve (SGR) and their implication on community’s livelihood in Vikumbulu Ward of Kisarawe District, Tanzania. Socio-economic data from Kisarawe District and TNBS were linked to spatial data to offer an integrated perspetive of LULC change in the Ward. Three cloud free image dates of 1998, 2011 and 2015 were analysed using System for Automated Geoscientific Analyses (SAGA) GIS for three categories of land cover, i.e. forest, wooded grassland and bare land/settlements/cultivation. Vikumbulu demographic and socio-economic data were linked to spatial data applying distance as a function of LULC change. Spatial analysis has shown a decreasing trend of forest and woodland cover in Vikumbulu Ward between 1998 and 2015. The sharp decline indicates increasing social economic activities such as shifting agriculture and charcoal burning as an outcome of population growth and poverty. Rapid conversion of forest cover to wooded grassland occurred between 1998 and 2015 in Vikumbulu Ward. However, loss of forest cover was associated with a decreasing trend in wooded land in the ward between 2011 and 2015. As there was only 0.15% area under crop cultivation in Vikumbulu until 2015, it is highly likely that LC change is caused by charcoal burning and shifting cultivation. This study suggests developing integrated strategies that target LULC change, conservation and people’s livelihoods to effectively improve the current situation in rural areas of Tanzania.

关键词： Land Use and Land Cover Changes Poverty Charcoal Vikumbulu Wards SGR Buffer Zones

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印度西高止山Agastyamalai地区生物多样性层隙分析的植被学途径

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人类环境杂志 1997年第8期26卷 521-528页

作者： B.R.Ramesh Shaily Menon kamaljit S.Bawa 罗天祥 (印度)本地治里法国研究所波士顿马萨诸塞大学波士顿马萨诸塞大学生物系

在印度,历史上按某种特定方式已建立的保护区一直很少注意到某一地区的资源保护价值。这里着重研究印度西高止山(WG)Agastyamalai地区的保护区群。我们分析了该地区从本世纪初到1960年期间以及从1960年到1990年期间的森林面积减少和土... 详细信息

在印度,历史上按某种特定方式已建立的保护区一直很少注意到某一地区的资源保护价值。这里着重研究印度西高止山(WG)Agastyamalai地区的保护区群。我们分析了该地区从本世纪初到1960年期间以及从1960年到1990年期间的森林面积减少和土地利用变化。研究中采用GIS技术对该地区的保护区进行了生物多样性层隙分析,绘制了现有植被类型的详细分布图,并利用这一植被图生成了分别与植物种类丰富度、植物特有种分布区、独特的植物生境区以及典型特有动物种群栖息地分布等相对应的多层专题图。将这些专题图与保护区网络分布图相叠加,显示了资源保护价值高但未能合理保护的地区。在这一研究地区出现森林采伐率高,一些生物多样性价值高的地区未列入最高级别的保护对象。我们提出这一方法旨在进一步建立一种资源保护的利用价值指数,以确定资源保护与管理的重点。

关键词：印度西高止山植被学 Agastyamalai 生物多样性

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