habitat evolution

Habitat Evolution Mapping Project Decadal Update 2019 & 2021 Final Report

ariela — Thu, 10 Nov 2022 00:14:02 +0000

Habitat Evolution Mapping Project Decadal Update 2019 & 2021 Final Report

Field photo of marsh habitat

ariela Wed, 11/09/2022 - 16:14

Document Category

Scientific Reports

Author(s)

Date

2022-10

Summary

Despite fluctuations in acreages between years, the marshes and mudflat south of the San Mateo bridge appear relatively stable between the period 2009 – 2021, in that the relative proportions between different habitat types have not changed significantly. Within a number of restored ponds (e.g., A21, A20, E8A, and North Creek Marsh) there has been larger growth in marsh vegetation when compared to the entire study area. Although the most significant floral colonization and growth of vegetation in many of the restored ponds occurred over the eight years between the end of HEMP1 (2011) and the beginning of HEMP2 (2019), the rate of vegetative growth within some of these restored ponds significantly increased over the two years between 2019 and 2021 suggesting that areas of these ponds may have reached an elevation conducive to vegetation establishment. Marsh expansion also continues to occur outside of some restored ponds including at Calavaras Marsh, the fringe marsh above Pond A6, and at Ogilvie Island. At the same time, there is also evidence of marsh erosion in some locations, including up to 50 meters at Whale’sTail and 10 meters at the mouth of Ravenswood Slough.

Overall, the tidal mudflats directly facing the bay (i.e., not within ponds or sloughs) south of the San Mateo bridge appear to be relatively unchanged since imagery collected in 2016. Although tidal mudflats directly exposed to the bay remain relatively unchanged since 2016 there are some locations with evidence of accretion and/or erosion. There is also a decrease in the acreage of mudflats within restored ponds due to floral colonization.

There may be correlative environmental, climatic, and anthropogenic factors influencing biotic and abiotic distributions that are not accounted for in this study. These include but are not limited to: temperature, precipitation, tidal changes, sediment accretion/erosion, soil and water salinity, and the restoration itself. We encourage the use of these datasets to inform other studies and help elucidate any role these factors might have in vegetation/habitat distributions and the evolution of marshes in the South Bay.

Keywords

habitat evolution

habitat characteristics

tidal marshes

mudflats

mapping

multispectral imagery

Pond Complex

Alviso

Eden Landing

Ravenswood

Content available here

https://bfa.egnyte.com/dl/8ppJyNlBa4

South Bay Salt Ponds Restoration Project Final Data Acquisition Plan

admin — Thu, 23 Nov 2017 00:21:53 +0000

South Bay Salt Ponds Restoration Project Final Data Acquisition Plan admin Wed, 11/22/2017 - 16:21

Document Category

Scientific Reports

Author(s)

H.T. Harvey & Associates

Date

2004-03-25

Keywords

birds

fish

habitat evolution

trail use/public access

South Bay Salt Pond Restoration Project: Annual Report 2014

ariela — Thu, 23 Jun 2022 20:23:43 +0000

South Bay Salt Pond Restoration Project: Annual Report 2014

2014 Annual Report cover

ariela Thu, 06/23/2022 - 13:23

Document Category

Progress Reports

Author(s)

SBSP Project Management Team

Date

02-2015

Summary

A yearly snapshot of Project milestones and assessment of progress toward meeting restoration, public access and flood management goals

Keywords

habitat characteristics

trail use/public access

fish

mercury

South Bay Salt Pond Restoration Project: Annual Report 2013

ariela — Thu, 23 Jun 2022 20:06:07 +0000

South Bay Salt Pond Restoration Project: Annual Report 2013

2013 Annual Report cover

ariela Thu, 06/23/2022 - 13:06

Document Category

Progress Reports

Author(s)

SBSP Project Management Team

Date

03-2014

Summary

A yearly snapshot of Project milestones and assessment of progress toward meeting restoration, public access and flood management goals

Keywords

trail use/public access

South Bay Salt Pond Restoration Project: Annual Report 2012

ariela — Thu, 23 Jun 2022 19:30:08 +0000

South Bay Salt Pond Restoration Project: Annual Report 2012

2012 Annual Report cover

ariela Thu, 06/23/2022 - 12:30

Document Category

Progress Reports

Author(s)

SBSP Project Management Team

Date

03-2013

Summary

A yearly snapshot of Project milestones and assessment of progress toward meeting restoration, public access and flood management goals

Keywords

trail use/public access

Habitat Evolution Mapping Project Decadal Update (2019 & 2021) - Preliminary Results (2019)

ariela — Thu, 27 May 2021 00:44:10 +0000

Habitat Evolution Mapping Project Decadal Update (2019 & 2021) - Preliminary Results (2019)

2019 Study Area. Credit: Brian Fulfrost & Associates

ariela Wed, 05/26/2021 - 17:44

Document Category

Scientific Reports

Author(s)

Brian Fulfrost

David Thomson

Matt Hinshaw

Date

2021-05

Summary

This report outlines the preliminary results of the 2019 update to the original Habitat Evolution Mapping Project (HEMP). HEMP mapped the marshes and mudflats south of the San Mateo bridge yearly between 2009 and 2011. This update to that project (which we refer to as “HEMP2”), is a two-year project designed to understand the current status of these habitats, and to map and quantify the changes over the last decade. Originally planned for 2019 and 2020, the second year of HEMP2, was moved to 2021 and is now underway. The goal of the update is to better inform the South Bay Salt Pond Restoration Project (SBSP), its partners and stakeholders, about the status of marsh and mudflat habitats within the study area and to assess changes to these habitats since the first study a decade ago.

The preliminary datasets produced from the HEMP2 study, and presented in this report, provide the SBSP Project Management Team (PMT) important resources for quantifying and visualizing the current distribution and extent of tidally influenced salt, brackish and freshwater marshes, as well as tidal mudflats, within the study area (See Figure 1). In combination with the results from the first phase of HEMP (Fulfrost, B., Thomson, D., 2012), they also allow the PMT and its’ partners and stakeholders to better understand how tidal marshes have evolved over the last decade (2009-2019). We cannot assess changes to mudflats for this same period since we were unable to use the mudflat data from the previous report as a good baseline. However, we do now have mudflat distribution and extent from 2016 (Fulfrost, B., 2017), and we applied these same methods to the 2019 imagery.

Overall, vegetation communities within tidal marshes have remained relatively stable, especially within fringe marshes along sloughs and marshes that already are well established. Based on our preliminary acreage tables for the entire study area (see Figure 3), there has been a small increase in the acreage of low salt marsh and a subsequent small decrease in the “mid” marsh plain. At the same time there also appears to be an overall increase in brackish marsh, especially in the Alviso area (and adjacent marshes). These overall trends could be variability across years, differences in the application of methods, or even some stochastic combination of factors.

Within the restored ponds, the trends and changes are much easier to understand (and quantify). Within several restored ponds there has been a significant increase in floral colonization (e.g. E9/E8A, A21, A20, North Creek marsh), but not as much in others (A6 & A17). The ponds with less floral colonization have changed into large mudflats, where biofilm also predominates. In some locations, such as the Alviso restoration unit, there also appears to be an in increase in brackish marsh since 2009-211. It is unclear whether this is interannual variability or a potential general shift in salinity.

Overall, the tidal mudflats directly facing the bay (i.e. not within ponds or sloughs) south of the San Mateo appear to be relatively unchanged from 2016. The contour of MLLW provided by the USGS from 2005 (Jaffee, B. & Foxgrover, A., 2006), also shows a general spatial correspondence with the current extent. Although tidal mudflats directly exposed to the bay remain relatively unchanged since 2016 (and even 2015), there are some locations with evidence of accretion and/or erosion. Although it is to be expected, there is also a decrease of mudflats within restored ponds with floral colonization.

Keywords

habitat evolution

mudflats

mapping

multispectral imagery

Pond Complex