Climate change and annual rainfall depths

I want to know whether gravel formed in river by natural process is better than the gravel made in crusher from any perspective. Please, share your experience and knowledge.

I have modeled the PMF of of a particular river but the available observed discharges are too small compared to the PMF value so, how do i calibrate the model with this limitation. thak you

The differences in understory vegetation diversity and composition between monoculture and mixed plantations of hybrid poplar and spruce have significant implications for ecosystem processes. Mixed plantations, with their more diverse understory vegetation, tend to have a more complex nutrient cycle. This diversity promotes nutrient retention and reduces leaching, whereas monocultures are more likely to experience nutrient depletion. Furthermore, the varied root systems and litter inputs from diverse understory vegetation in mixed plantations enhance soil carbon sequestration. In contrast, monocultures typically have lower soil carbon storage due to reduced litter inputs and simpler root systems.

introduction and different process of hydrologic cycle

Currently doing a surface run-off analysis in a small watershed. Instead of Precipitation gage, I'm using ERA5 hourly data (Precip, Temp, Solar). But somehow my basin cells doesn't detect the precip data, all of them are missing data.

So far my workflow for importing ERA5 are:

1. Import .nc4 or .grib2 data using import wizard or HEC-Vortex

2. .dss setting are > UTM50S (match my terrain data) > override data type to PER-CUM.

3. Create grid component > Then I validate grid data which return as valid. I also opened the .dss in HEC-DSS Vue which looks pretty normal

4. With other parameters are filled (Loss, transform, discr, etc), I created run using the same Met and Basin Model.

5. The Run returned with errors that cells in subbasins cannot find the precipitation data

so far I have tried:

1. Clipped the .dss file with my subbasins.

2. Transpose the Met Model to match the clipped .dss storm center

3. Override the unit in .dss file

4. Filling Part A (grid system) and Part B (watershed name) in import wizard.

5. importing the nc4 with default setting as in SHG grid system and 2000 cell size

6. Forcing my terrain data using SHG or NAD83 / Albert Conus CRS reprojection (now somehow I can't delineate in HMS)

If anyone can kindly answer or give reference (currently dwelling on HMS manual and Tim Nelson HMS Video)

Hi all,

I have a question regarding the relationship between evaporation and groundwater fluctuations. Does evaporation cause groundwater to fall, or does rising groundwater lead to increased evaporation?

By "evaporation," I mean actual evapotranspiration from the land surface, as defined by most evapotranspiration models (e.g., GLEAM, MERRA).

I believe this process can be described using a conceptual model:

Imagine a cup of water with green beans soaking in it, covered by a lid. When the lid is opened, water evaporates, and as the water level decreases, does the evaporation (per unit of time) also decrease? The answer is yes, indicating that groundwater (represented by the cup of water) influences evaporation.

Now, imagine the cup is topped by a sponge (representing the unsaturated zone). If we measure evaporation from the top of the sponge (which should represent actual evapotranspiration at the land surface), the evaporation will still decrease as the water in the cup (groundwater) decreases. However, there should be a time lag because groundwater evaporation reaches the sponge first.

This concept is especially relevant for soils, where soil evaporation is derived from both past groundwater evaporation and past precipitation infiltration. Similarly, for vegetation transpiration, a rising water table would lead to increased water uptake by vegetation, thereby increasing transpiration. Again, a time lag would be expected in this process.

In other words, according to this conceptual model, actual evapotranspiration at the land surface tends to lag behind groundwater evaporation.

With this in mind, is it correct that groundwater recharge analysis should subtract evapotranspiration from precipitation and then calculate recharge per unit of time? In particular, in some common response analyses, recharge is considered as the net of precipitation minus evaporation, and then the groundwater time series is fitted with a gamma function or other response functions. However, doesn't this treatment implicitly assume that higher evaporation leads to lower groundwater levels in the future?

However, shouldn't evaporation be a “sink” rather than a “source” of groundwater? Shouldn't the only components of evapotranspiration that affect recharge be vegetation indicating interception losses and soil interception?

Please let me know your answer.

I am sure about the NDVI products deprived from the satellites images will provide the vegetation richness. However, I wanted to know how can estimate the Biodiversity (only Flora) richness using NDVI or any others means of method available.

Instead of a generalized explanation, I expect a detailed explanation. Any similar studies has carried out by any researchers, then please tag the research paper for references and further clarity.

Thank you

Mangroves significantly contribute to mitigating estuarine acidification through physical, chemical, and biological processes. But the exact mechanism is poorly understood. Protecting and restoring mangroves can thus be an essential strategy for maintaining the health and pH balance of estuarine ecosystems.

Hello, I am currently working on my undergraduate thesis, which focuses on modeling seepage through a dam. I am exploring the use of MODFLOW for this purpose, as it is widely recognized for simulating flow through porous media (based on information from the USGS website and my advisor's suggestion). However, I have been struggling to find relevant papers, case studies, or comprehensive tutorials to guide me in this specific application, which has left me feeling a bit overwhelmed. Additionally, the numerous add-ons and plugins available for MODFLOW make it challenging to understand their differences and how they might apply to my work. I would greatly appreciate any explanations, references, or resources that could help me better understand this topic. Thank you very much!