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Long-term tree productivity of a South Carolina coastal plain forest across a hydrology gradient

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Journal of Plant Ecology 2011年第1期4卷 67-76页

作者： William H.Conner Bo Song Thomas m.Williams jeffery T.Vernon Baruch Institute of Coastal Ecology and Forest Science Clemson UniversityGeorgetownSouth Carolina 29442USA

Aims In recent years,there has been an increased interest in examining changes in forest systems in response to drought,flooding,hurricanes and climate *** the southern United States,forested wetlands are of special interest because of the extent of these *** plain forested wetlands are among the most vulnerable to these climatic *** of the problems in developing management practices for these coastal areas is the difficulty in adequately describing productivity relations and predicting how the structure and function of these communities might be affected by natural or anthropogenic *** response to environmental change often occurs over a period of years,and the majority of reported studies are for 1–3 years in *** study documents long-term changes(10 years)in structure,composition and growth along a catena of high water table forested sites of an ancient beach ridge landscape in coastal South *** Aboveground net primary production(ANPP)of trees was monitored from 2000 to 2009 on three sites within a longleaf pine-swamp blackgum forest system on the southern end of theWaccamaw Neck area of Georgetown County,*** study plots(20325 m)were established across a moisture gradient(Dry,Intermediate,and Wet).Water levels were continuously monitored,litterfall was measured monthly and growth of trees>10 cm diameter at breast height was monitored on an annual *** litterfall and tree production values were summed to provide estimates of *** Findings The study site was under severe drought conditions July 2001 through late summer 2002 and again in *** growth was affected in all three sites,but with different *** seems that diameter growth in the Wet site was more sensitive to drought conditions in 2001–02 and 2007 than either Dry or Intermediate *** droughts did not seem to have a significant impact on litterfall in the Wet site,litterfall in the Intermediat

关键词： production gum-cypress forests hydrology drought effects coastal plain forests

The relationship between controllability, optimal testing resource allocation, and incubation-latent period mismatch as revealed by COVID-19

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Infectious Disease modelling 2023年第2期8卷 514-538页

作者： jeffery Demers William F.Fagan Sriya Potluri Justin m.Calabrese Center for Advanced Systems Understanding(CASUS) Helmholtz-Zentrum Dresden-Rosendorf(HZDR)G€orlitzGermany Dept.of Biology University of MarylandCollege ParkMDUSA Dept.of Ecological modelling Helmholtz Centre for Environmental Research-UFZLeipzigGermany

The severe shortfall in testing supplies during the initial COVID-19 outbreak and ensuing struggle to manage the pandemic have affirmed the critical importance of optimal supplyconstrained resource allocation strategies for controlling novel disease *** address the challenge of constrained resource optimization for managing diseases with complications like pre-and asymptomatic transmission,we develop an integro partial differential equation compartmental disease model which incorporates realistic latent,incubation,and infectious period distributions along with limited testing supplies for identifying and quarantining infected *** model overcomes the limitations of typical ordinary differential equation compartmental models by decoupling symptom status from model compartments to allow a more realistic representation of symptom onset and presymptomatic *** analyze the influence of these realistic features on disease controllability,we find optimal strategies for reducing total infection sizes that allocate limited testing resources between‘clinical’testing,which targets symptomatic individuals,and‘non-clinical’testing,which targets non-symptomatic *** apply our model not only to the original,delta,and omicron COVID-19 variants,but also to generically parameterized disease systems with varying mismatches between latent and incubation period distributions,which permit varying degrees of presymptomatic transmission or symptom onset before *** find that factors that decrease controllability generally call for reduced levels of non-clinical testing in optimal strategies,while the relationship between incubation-latent mismatch,controllability,and optimal strategies is *** particular,though greater degrees of presymptomatic transmission reduce disease controllability,they may increase or decrease the role of nonclinical testing in optimal strategies depending on other disease factors like transmissibility

关键词： Testing quarantine control Optimal resource allocation Presymptomatic transmission Latent period Incubation period Age of infection

Black soldier fly(Diptera:Stratiomyidae)larval heat generation and management

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Insect Science 2023年第4期30卷 964-974页

作者： Chujun Li Nicola F.Addeo Travis W.Rusch Aaron m.Tarone jeffery K.Tomberlin Department of Entomology Texas A&M UniversityCollege StationTexas State Key Laboratory of Biocontrol School of Life ScienceSun Yat-sen UniversityGuangzhouChina Guangzhou Unique Biotechnology Co. LtdGuangzhouChina Department of Veterinary medicine and Animal Production University of Napoli Federico llNapoliItaly

mass production of black soldier fly,Hermetia illucens(L.)(Diptera:Stra-tiomyidae),larvae results in massive heat generation,which impacts facility management,waste conversion,and larval *** tested daily substrate temperatures with dif-ferent population densities(i.e.,0,500,1000,5000,and 10000 larvae/pan),different pop-ulation sizes(i.e.,166,1000,and 10000 larvae at a fixed feed ratio)and air temperatures(i.e.,20 and 30℃)on various production *** of shifting larvae from 30 to 20℃on either day 9 or 11 were also *** activity increased substrate tem-peratures significantly(i.e.,at least 10℃above air temperatures).Low air temperature favored growth with the higher population sizes while high temperature favored growth with low population *** greatest average individual larval weights(e.g.,0.126 and 0.124 g)and feed conversion ratios(e.g.,1.92 and 2.08 g/g)were recorded for either 10000 larvae reared at 20℃or 100 larvae reared at 30 *** temperatures from high(30℃)to low(20℃)in between(~10-d-old larvae)impacted larval production weights(16%increases)and feed conversion ratios(increased 14%).Facilities should consider the impact of larval density,population size,and air temperature during black soldier fly mass production as these factors impact overall larval production.

关键词： Allee effect density Hermetia illucens industry substrate heat thermal ecology

Effects of anaerobic digestion and aerobic treatment on the reduction of gaseous emissions from dairy manure storages

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International Journal of Agricultural and Biological Engineering 2008年第2期1卷 15-20页

作者： Ruihong Zhang jeffery A.mcGarvey Yanguo ma Frank m.mitloehner Biological and Agricultural Engineering Department University of CaliforniaDavisCAUSA US Department of Agriculture Agricultural Research ServiceFoodborne Contaminants Research UnitAlbanyCAUSA Animal Science Department University of CaliforniaDavisCAUSA

Effects of anaerobic digestion and aerobic treatment on the reduction of gaseous emissions from dairy manure storages were evaluated in this *** dairy manure containing 3.5%volatile solids(VS)was either anaerobically digested or aerobically treated prior to storage in air-tight *** digestion was carried out using a mesophilic anaerobic sequencing batch reactor operated at a hydraulic retention time of 20 days and an organic loading rate(OLR)of 1 gVS/L/*** treatment was achieved using an aerobic reactor operated at a hydraulic retention time(HRT)of 10 days and an OLR of 2 gVS/(L·d).The treated manure was put into the storage on a daily basis for a period of 180 *** the gases produced during this period were captured and analyzed for methane,carbon dioxide and volatile organic compounds(VOCs).Untreated manure was stored and analyzed in the same way as the treated manure and used as a control for *** results show that low amounts of gases were produced during the first 84 days of storage in both treated and untreated manure,but increased significantly after this time *** generally expected positive impacts of anaerobic and aerobic treatment on the reductions of methane and VOCs were confirmed in this ***,the effects of anaerobic and aerobic treatment varied over the time of storage,especially for *** results of this study indicate that to achieve significant reductions in VOC emission the storage time of anaerobic digester or aerobic reactor effluent should be limited to no more than 100 days.

关键词： anaerobic digestion aerobic treatment methane volatile organic compounds dairy manure

Forest protected area governance in Bangladesh:a focus on the legal and policy framework

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Chinese Journal of Population,Resources and Environment 2013年第4期11卷 345-351页

作者： A.Z.m.manzoor Rashid Donna Craig michael I.jeffery Niaz Ahmed Khan Department of Forestry and Environmental Science Shahjalal University of Science and Technology Environmental Law School of LawUniversity of Western Sydney Department of Development Studies University of Dhaka

In the context of renewed interest in collaboration in natural resource management,the collaborative governance approach has lately been introduced to the forest Protected Areas(PAs)in *** adoption of this co-management approach is seen as an attempt to influence the governance process towards a transformation from the conventional custodian system to a more participatory management *** of rights and responsibilities,effective participation,and equitable distribution of benefits amongst the key stakeholders working under a facilitative policy and legal framework are believed to address the broader goals of sustainable development Notwithstanding the resurgence of interest in governance of forest PAs through the co-management approach,academic research on the subject remains *** article attempts to review selected key information and milestones on the forest PAs governance with special reference to the major policies and legal *** a brief introductory section,this article focuses on the genesis and selected major features of the Forest PAs in the *** discussion then dwells on the policy and legal framework and provides a critique on its relevance for promoting community *** existing institutional arrangements for community engagement in protected area governance are also analyzed in light of the national and international commitment and policy obligations on the part of the *** salient observations and key findings of the study include the following:(1)despite its limitations,comanagement as concept and practice has gradually taken roots in Bangladesh;(2)the degree and level of active community participation remain low and limited,and there is also clear weakness in conscientizing and orientating the local community on the key legal and policy issues related to PA governance in the country;and(3)policy makers,practitioners,and other local stakeholders related to PA governance need to be orien

关键词： governance protected areas participation community decision-making organizations

A New Species of Japalura(Squamata, Agamidae) from the Nu River Valley in Southern Hengduan mountains, Yunnan, China

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Asian Herpetological Research 2017年第2期18卷 86-95页

作者： Dingqi RAO Jens V.VINDUm Xiaohui mA mingxia FU jeffery A.WILKINSON Kunming Institute of Zoology Chinese Academy of Sciences Department of Herpetology California Academy of Sciences

A population of Japalura from Yunnan Province, China, previously assigned to Japalura splendida, is described as a new species. The new species has been recorded between 1 138–2 500 m in the Nu River drainage between the towns of Liuku and Binzhongluo, and on the lower western slopes of the Nushan and eastern slopes of the Goaligongshan. The new species can be distinguished from other species of Japalura, except J. dymondi, by the following combination of characters： exposed tympani, prominent dorso-lateral stripes, and small gular scales. It is very similar with but differs from J. dymondi by having smooth or feebly keeled dorsal head scales, three relatively enlarged spines on either side of the post-occiput area, strongly keeled and mucronate scales on occiput area and within the lateral stripes, back of arm and leg green, higher number of dorsal-ridge scales（DS） and fourth toe subdigital scales（T4S）. A principal component analysis of body measurements of adult male specimens of the new species and J. dymondi showed principal component 1 loading highest for upper arm length, fourth toe length and snout to eye length and principal component 2 loading highest for head width, head length and fourth toe length.

关键词： Agamidae Japalura sp.nov. Goaligongshan mountain Nujiang River Valley Hengduan mountains Yunnan China

Tolerance to Zn deficiency and P-Zn interaction in wheat seedlings cultured in chelator-buffered solutions

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Journal of Arid Land 2011年第3期3卷 206-213页

作者： WenXuan mAI XiaoHong TIAN Willam jeffery GALE XiWen YANG XinChun LU College of Resources and Environment Northwest A＆F University Yangling 712100 China Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Zinc deficiency is a common constraint for wheat production in the regions with limited precipitation,particularly in the regions with high levels of available phosphate （P） in *** experiments were conducted using chelator-buffered nutrient solutions to characterize differences in tolerance to Zn deficiency among three winter wheat （Triticum aestivum L）.genotypes and to investigate the relationship between P and Zn nutrition in wheat *** indices,Zn efficiency,relative shoot-to-root ratio,total Zn uptake in shoot,and shoot dry weight were used to compare the tolerance to Zn deficiency among three wheat *** results indicated that the four indices could be used in breeding selection for Zn uptake-efficient *** genotype H6712 was the most tolerant to Zn deficient,followed by m19,and then ***,H6712 had the highest Zn uptake efficiency among the three *** addition of P to the growth medium increased Zn uptake and translocation from roots to *** Zn content of the wheat plant was 43% higher with 0.6 mmol/L P treatment than that of control with 0 mmol /L P *** Zn translocation ratios from roots to shoots were increased by 16% and 26% with 0.6 mmol/L P treatment and 3 mmol/L P treatment,respectively,compared with 0 mmol/L P *** contrast,high Zn concentrations in the growth medium inhibited P translocation from roots to shoots,but the inhibitive effects were not ***-six percent of P taken up by wheat plants was translocated to the wheat shoots at 0 μmol/L Zn treatment,while the percent was 60% at 3 μmol/L Zn *** result may be due to the fact that the wheat plants need more P than Zn.

关键词： chelator-buffered solution tolerance to Zn deficiency P and Zn interaction

Cohort contributions to trends in the incidence and mortality of intrahepatic cholangiocarcinoma

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Hepatobiliary Surgery and Nutrition 2018年第4期7卷 270-276页

作者： Eliza W.Beal Dmitry Tumin Dimitrios moris Xu-Feng Zhang jeffery Chakedis mary Dilhoff Carl m.Schmidt Timothy m.Pawlik Department of Surgery Division of Surgical OncologyThe Ohio State University Wexner Medical Center and James Cancer Hospital and Solove Research InstituteColumbusOHUSA Department of Anesthesiology and Pain medicine Nationwide Children’s HospitalColumbusOHUSA Department of Hepatobiliary Surgery and Institute of Advanced Surgical Technology and Engineering the First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710000China

Background: The incidence and mortality of intrahepatic cholangiocarcinoma (ICC) are increasing worldwide. We used age-period-cohort (APC) modeling to evaluate the contribution of cohort effects to trends in ICC incidence and mortality in the US. methods: Incidence data were acquired from the Surveillance, Epidemiology and End-Results (SEER) program. mortality data were obtained from the Centers for Disease Control and Prevention WONDER Database. APC models using restricted cubic splines were fitted to estimate change in incidence and mortality risk over age, and modification of incidence and mortality risks according to birth cohort and period of diagnosis or death. Likelihood ratio tests were used to summarize improvement in model fit with APC modeling. Results: There were 4,053 cases of ICC at SEER registry sites between 1973–2012. ICC incidence increased with older age and across all birth cohorts examined. Inclusion of cohort effects tended to improve model fit relative to an age-period model (likelihood ratio test P=0.082). The national crude ICC-related mortality rate increased from 2.9 to 5.0 per 100,000 among males and 2.7 to 4.6 per 100,000 among females. Among males, ICC mortality risk varied across birth cohorts, and inclusion of cohort effects in a model predicting ICC mortality risk improved model fit (likelihood ratio test P=0.001), but cohort effects did not alter model fit among females (P=0.223). Conclusions: ICC incidence and mortality have increased over time in the United States. Birth cohort effects influenced increased ICC incidence and ICC mortality among males, but were not evident in the trend of ICC mortality among females.

关键词： Intrahepatic cholangiocarcinoma (ICC) incidence mortality cohort effect age-period-cohort model (APC model)

Global Warming Impacts on Alpine Vegetation Dynamic in Qinghai-Tibet Plateau of China

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Journal of Geoscience and Environment Protection 2014年第3期2卷 54-59页

作者： Yan Qing Zhang jeffery m. Welker Department of Geography School of Computing Science Simon Fraser University Burnaby Canada Environment and Natural Resources Institute University of Alaska Anchorage Anchorage USA

This study is to illustrate alpine vegetation dynamics in Qinghai-Tibetan Plateau of China from simulated filed experimental climate change, vegetation community dynamic simulation integrated with scenarios of global temperature increase of 1 to 3°C, and simulated regional alpine vegetation distribution changes in responses to global warming. Our warming treatment increased air temperatures by 5°C on average and soil temperatures were elevated by 3°C at 5 cm depth. Above- ground biomass of grasses responded rapidly to the warmer conditions whereby biomass was 25% greater than that of controls after only 5 wk of experimental warming. This increase was accompanied by a simultaneous decrease in forb biomass, resulting in almost no net change in community biomass after 5 wk. Under warmed conditions, peak community bio-mass was extended into October due in part to continued growth of grasses and the postponement of senescence. The Vegetation Dynamic Simulation model calculates a probability surface for each vegetation type, and then combines all vegetation types into a composite map, determined by the maximum likelihood that each vegetation type should distribute to each raster unit. With scenarios of global temperature increase of 1°C to 3°C, the vegetation types such as Dry Kobresia meadow and Dry Potentilla Shrub that are adapted to warm and dry conditions tend to become more dominant in the study area.

关键词： Global Warming Alpine Vegetaion Qinghai-Tibet Plateau