A typical along-fjord DO distribution may show higher oxygen at the mouth and lower oxygen near the head

Considering that many local marine species, including wild Pacific salmon, experience adverse effects at oxygen concentrations much higher than the hypoxic threshold, we note that 50 to 100% of the upper 50 m of Herbert Inlet consistently presented low oxygen concentrations (defined here as a guideline as ≤ 4.9 mL L-1 or 6.9 mg L-1)

An important concept is the joint variation or the expected value ofthe product of the two variables, where each one is centered at the mean.

Exercise 2.6Define an RV from the outcome of soil moisture measurements in the range of 20–100% in vol-ume. Give an example of an event. Assuming that it can take values in [20,100] uniformly, plot thepdf and cdf. Calculate the mean and variance.Exercise 2.7At a site, the monthly air temperature is normally distributed. It averages to 20°C with a standarddeviation of 4°C. What is the probability that the value of the air temperature in a given monthexceeds 24°C? What is the probability that it is below 16°C or above 24°C?The exponential pdf is given byp x a ax( ) exp( )= − (2.34)and the cdf is given byF x ax( ) exp( )= − −1 (2.35)It has mean and variance equal to σX Xa a= =1 12 2/ /and , respectively.–40.00.2p(Z)0.4–2 0Z2 4–z0 z00.00.4F(Z)0.8–4 –2 0Z2 4–z0 z0FIGURE 2.13 Standard normal pdf and cdf.

As another example, consider an RV normally distributed with mean = 1 and variance = 0.25.What is the probability of obtaining a value in between 0.5 and 1.5? The standard deviation is 0.5. Thisinterval is one standard deviation away from the mean on each side. Therefore, the probability is 0.68

Another way of looking at this is to think of the pdf as a theoretical model expressing the under-lying probability structure of the RV. These functions allow for the calculation of the moments.However, the statistics are calculated from the observed data and are used to estimate the moments.

To calculate it, we need the pdf of the RV.The mean is not the same as the statistic known as the sample mean

probability density function (pdf)

This is the same as the mean of X

d dX / t aX= is a dynamic model. In this case, it is given by an ODE.• X(t) is the state variable at time t. In this case, the state could also be called the output. Inother cases, the output is a function of the state.• a is a parameter.• X(t0) is the initial condition or initial state (technically it is also a parameter

Assume that t1 = t and t0 = 0. Write the solution for the ODE of the example immediately above,using the initial condition X(0) = 1

Assume that a = b = 1 for the term in Equation 2.2. What is the area under the curve betweent = 2 and t = 6? Illustrate the area using a graph like the one given in Figure 2.6

Plot Equation 2.8 when b = −4 and a = 3. Find the values of the function and its derivative at t = b

For a = 2 and b = 4, we can see that this optimum is a minimum with a value a = 2 and it occursat b = 4 (Figure 2.5)

Assume that a = 1 and b = 2. Evaluate the derivative of X with respect to t for the X given inEquation 2.2 and plot it. Is the derivative a constant with respect to t? Is the derivative a linearfunction with respect to t

This derivative represents a rate of change of X

(2.4)

(2.1)

(2.2)

(2.3)

Use a variable X to denote human population on Earth. Explain why it varies and give an exampleof a value.

Furthermore, for those that hold thisschema, any deviation from the path(experiments that don’t work, studentsthat become depressed, etc.

t is remarkable that listening to our ownidiosyncratic voice leads to better science.It makes research self-motivated and theroutine of research more rewarding

Do not committo a problem before 3 months haveelapsed

Pareto front as a function of the life stagesof the scientist

We generally value science that venturesdeep into unknown waters.

been turned down multiple times by NIH’speer-review system

DOD’s can-do approach, its enthusiasm about partnering withpatient-advocates, and its dedication to solving the problem of breastcancer

including excessive bureau-cratic growth, interference from Congress, and long-term commitmentsto hugely expensive and troubled weapons systems with little civilianspillover potential, such as missile defense and the F-35 joint strikefighter — the Pentagon’s creativity and productivity as an innovator hassignificantly dissipated

he Boeing Company could take the jet-engine-powered aerialfuel tanker it was developing for the Air Force and use a similar designfor its 707 passenger jet,

But DOD also supported the science needed to keepinnovation going

but when it is steered to solve problems — especially thoserelated to technological innovation

but only scientists couldevaluate the research they were doing

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Another possibility is that the disturbance protocols,337 although being of standardised duration, had differing impacts on individuals due to variation338 in their size/ mass, physiological state, energy reserves and stamina. Using the same duration339 of exercise for all fish is therefore not necessarily representative of what they would340 experience in true catch and release angling, where fish with greater stamina will tend to be341 exercised for longe

the observed effects329 of the simulated C&R protocols on offspring mortality and viability in the present study were330 independent of whether the stressor was applied to the mother or father

Egg mortality was lower in families where the experimental parent was trapped towards the314 end of the collection period. Since fish could not bypass the trap on their upstream migration,315 and the trap was emptied daily, late-trapped fish were possibly those that had entered the316 river relatively late in the migration season and so may have been feeding more recently (and317 so were in better body condition) than those captured earlier. Alternatively, the impact of318 C&R angling on subsequent reproduction may depend on the maturational state of the319 gametes at the time of the angling event, as suggested for other causes of parental stress

total offspring mortality within the first299 three months of feeding was higher when the experimental parent had been exposed to air,300 with the effect primarily arising from a greater vulnerability to the fungus Saprolegnia spp.,301 leading to a higher mortality during a 12-day fungal outbreak

there was no effect on the date of first feeding. What was affected was the size of297 the offspring: individuals from the extended air exposure group were smaller at first feeding298 compared to those from the control group

Additionally, the offspring yolk sac volume (YSV) was smaller in294 the groups where the experimental parent, again irrespective of sex, had been subjected to295 exercise and air exposure

there was292 evidence of higher egg mortality from parents (of either sex) that had been exposed to air for293 an extended period (120 s).

Table 1 Summary of the four treatment groups used in the experiment and cumulative levelsof acute disturbance they represent, indicated by the number of asterisks.

at least 5 fry were actively consuming feed

Dead eggs were removed from the trays daily, to prevent any fungal growth from spreading165 to healthy neighbouring eggs

fungus Saprolegnia spp.

its eggs were fertilised with the sperm from a randomly-selected non-136 experimental male

fish being hooked and potentially incurring129 physical damage to the mouth

but angling at this126 time of year is allowed elsewhere

storage

Direct measurements present opportunities to scale up andcompare against remotely sensed estimates

Where forests overlay shallow soils

evergreen broadleaf trees like English holly

however native madrone

Moreover, forest species composition isactively shifting due to management practices like logging, the spread of introduced (non-native,sometimes “invasive”) species, and anthropogenic climate change

the existence ofdifferent hydrological niches translates to larger patterns in forest health and environmental functionthrough space and time

soil appears thin

which fellat an earlier time out of sync with maximum atmospheric evaporative demand

Along with discharge,transpiration is balanced within the water cycle by precipitation

intense storm events

Few studies compare water relations between species in the Pacific Northwest, andthere are no known studies including introduced species despite their growing prevalence, debatablenaturalization, and concerns they may monopolize groundwater

Critical Zone

Pacific salmon recovery plans remainunderfunded relative to the magnitude of the problem, andexisting restoration plans have not been fully implementedanywhere in the region

and other elements.

perhaps establishment of a central clear-inghouse where monitoring organizations can store and sharedata and other types of information, would enhance the valueof monitoring efforts

Because organizations that conduct monitoringare often unaware of other monitoring efforts in their area ofinterest, exchange of data and other important informationoften does not occur.

Most monitoring efforts have been directedtowards estimating abundance and productivity, as discussedabove. However, monitoring of spatial structure and diver-sity are increasingly being recognized as equally importantaspects of Pacific salmon response to habitat restoration

Based on modeling, Roni et al. (2010) concludedthat, on average, 20% of floodplain and in-channel habitatwould have to be restored to produce a 25% increase in CohoSalmon and steelhead smolt production

smoltcounts are often aggregates of multiple natal populations,which means the abundance trends can be difficult or impos-sible to associate with habitat changes caused by restoring aspecific stream reach

Furthermore, the habitat andfish population measurements must be collected in a mannerthat enables habitat changes due to restoration to be linked todemographic changes in Pacific salmon

These factors suggest that monitoring over adecade or more may be required to discern any meaningfultrends in either physical or biological response to restoration

To achieve a net improvement in Pacific salmon habitat,the quantity and quality of habitat lost must be less than theamount of habitat being restored

However, the cost ofconducting these detailed analyses is usually much less thanthe cost of implementing a large, but ultimately unsuccessful,restoration program.

Coordinating measures to improve habitat condition withactions to address other factors impacting Pacific salmonabundance will be required to recover populations.

Nonetheless, available results clearly indicate that anincreased emphasis on trophic processes in limiting factorassessments, restoration planning, and project selection iswarranted.

and identification andincorporation of all relevant determinants of survival

We sug-gest five primary factors, which are discussed in detail below: