There is concern regarding the loss of ecosystem goods and services as a result of land use changes such as the expansion and intensification of agricultural activities. Assessments of these interactions require innovative analyses that combine qualitative and quantitative economic analyses. The Millennium Ecosystem Assessment framework was applied to a peri-urban region in British Columbia, Canada to assess the effects of the integration of agricultural programs and the maintenance of waterfowl habitat located on the Pacific Flyway. The Delta Farmland & Wildlife Trust, a non-governmental organization, has implemented several activities to enhance ecosystem goods and services by cooperative programs among the agricultural community and wildlife interests. The successful collaborative framework has resulted in enhanced soil quality, increased biodiversity, and the maintenance of valuable agriculture and waterfowl habitat.
Increased agricultural production has contributed to global and local land use changes [
Because areas experiencing gains and losses are spatially unique, proportional constancy of a particular land cover type (habitat) at broader spatial scales (nationally) may not capture the impact of habitat change on wildlife at finer scales (regionally or locally). Thus, local changes in land use and their impacts on the ecosystem cannot be analyzed independently. To assess the ecological effects on the outcome of changes in land use, a framework of ecosystem goods and services is needed to provide a relative comparison that integrates both tangible (economic and quantitative) values and intangible (social, ecological, and qualitative) values [
Some ecological benefits are recognized by traditional economic analysis, for example crop or livestock production, while others, such as wildlife habitat or water quality are not. Reference [
The Lower Fraser Valley of British Columbia, Canada, is an example of the phenomena of landscape dynamics. This region is important for agricultural production, while also subject to development pressures, including various industries, urban residential expansion, transportation arteries (road and rail) connecting to port facilities, and tourism and recreation activities. In recognition of these pressures, the provincial government introduced regulations under the Agricultural Land Commission Act to restrict non-agricultural uses on the most productive soils within the province [
Within the Lower Fraser Valley, the municipality of Delta is located on the Pacific Flyway, an internationally significant migratory route and nesting area for migratory waterfowl [
Westham Island, in the Municipality of Delta, has a long and documented history of agriculture that has had an important role in providing value to the agricultural community as well as wildlife (i.e. waterfowl) habitat. According to the Agricultural Land Use Inventory provided by the province of BC, about 95% of the land on Westham Island is within the provincially-regulated Agricultural Land Reserve [
As agricultural land on Westham Island is a significant source of ecosystem goods and services [
This study assesses the interaction of agricultural production and the provision of ecosystem goods and services on Westham Island, in Delta, BC. The assessment focuses on the contributions that intangible values (e.g., wildlife habitat, pollination, etc.) provide, both spatially and temporally, through management of the lands; it also evaluates the effects of programs initiated by DF&WT, and discusses the importance of balancing agricultural and environmental land uses in the context of the published literature.
Westham Island (49˚05’15’’N, 123˚09’29’’W) is located within the municipality of Delta, a suburb of Vancouver, in southwestern British Columbia. This small island is in a productive agricultural region in the province (
References [
eco-and agro-tourism.
By adapting the spatial analysis outlined in [
The assessment was done within the scope of the DF & WT’s agricultural land stewardship programs. Two of the major programs that focus on wildlife habitat and soil quality are: 1) the Grassland Set-aside Stewardship Program and 2) the Winter Cover Crop Stewardship Program.
Starting in 1990s, this program has fostered agreements with co-operators (farmers) for a period of 1 - 4 years to encourage them to plant a locally adapted mix of grasses and legumes on harvested fields to restore soil structure and build soil fertility [
This initiative was introduced in 1990 and helps to share the economic cost of establishing a vegetative cover on vegetable fields before the winter season, in order to protect the soil from erosion, improve soil fertility, and provide feeding habitat for herbivorous waterfowl and shorebirds [
To address any conflicts related to agricultural land management and wildlife habitat, DF&WT consults and facilitates discussions with farming and conservation stakeholders. Through research and evaluation of DF&WT programs, the organization offers solutions to challenges to both agricultural production and wildlife habitat conservation.
Summer crop survey maps supplied by DF&WT from 2005 (
The changes in crop cover on Westham Island were calculated using Geographic Information Systems (GIS) analysis [
There has been a small net change of classified land area within the last decade, amounting to a slight decrease of 2.5 ha. The category of Unknown Crops identified in 2005 is assumed to be accounted for within the other categories in 2015, and not lost to non-agricultural development. Aside from Unknown Crops, the largest change is in the area devoted to Vegetables, with a decrease of 42.6 ha. There was a relative increase in Other Land and Wild Land categories.
As crop rotation is considered to promote soil fertility and pest control, farmers are encouraged to practice crop rotation by the BC Ministry of Agriculture and Lands [
From the spatial analysis detailed in
Crop Cover | 2005 (ha) | 2015 (ha) | Changes in Area (ha) |
---|---|---|---|
Other Land | 10.7 | 47.4 | 36.7 |
Wild Land | 4.90 | 41.5 | 36.5 |
Grass/Forage | 99.0 | 131 | 32.4 |
Uncultivated | 51.1 | 75.1 | 23.9 |
Berry/Small Fruit | 42.8 | 74.3 | 31.6 |
Vegetables | 400 | 357 | -42.6 |
Grain | 62.3 | 47.1 | -15.2 |
Unknown Crops | 106 | 0.0 | -106 |
Total/Net | 777 | 773 | -2.5 |
important to note that the results are a snapshot of the land cover at the time of the survey, and may not represent the land cover throughout the year, as crop-free land may simply be in the process of replanting. However, the numbers presented in
Changes have taken place in Uncultivated Land between 2005 and 2015, which have converted to either Grass/Forage (16 ha), Grain (13 ha), or Berry/Small fruit (11 ha). With these conversions, the wildlife habitat value appears to have shifted. Meanwhile, 96% (72 out of 75 ha) of 2015 Uncultivated Land was transferred from other crops, mainly from Grain fields (36 ha) and Vegetable fields (29 ha). It should be noted that with the nature of the windshield survey, Uncultivated Land does not necessarily mean “barren” land; it may not have been planted for the season at the time of the survey.
The DF&WT Winter Cover Crop Stewardship Program has been incorporated into many farmers’ rotations on Westham Island. Through this program, farmers plant cereal grasses, clover, or annual forage grasses as a cover crop. Cover crops can be under-seeded into growing crops (e.g., cereal grains and silage corn) or planted after cash crops (e.g., beans, peas, and potatoes) have been harvested [
2005 | Vegetable | Grass/Forage | Grain | Berry/Small Fruit | Wild Land | Uncultivated | Unknown Crops | Other Land | Sum |
---|---|---|---|---|---|---|---|---|---|
2015 | |||||||||
Vegetable | 250 | 38 | 9.6 | 4.1 | 0 | 6.6 | 49 | 1.2 | 360 |
Grass/Forage | 41 | 45 | 8 | 2.3 | 3.3 | 16 | 12 | 3.8 | 130 |
Grain | 9.9 | 8.9 | 0 | 0 | 1.7 | 13 | 13 | 0 | 47 |
Berry/Small Fruit | 18 | 2.5 | 0 | 34 | 0 | 11 | 0 | 8 | 74 |
Wild Land | 17 | 0 | 0 | 0 | 0 | 0 | 24 | 0 | 42 |
Uncultivated | 29 | 3.3 | 36 | 1.5 | 0 | 2.9 | 0 | 2.5 | 75 |
Other Land | 35 | 1.9 | 8.6 | 0.6 | 0 | 0.5 | 7.8 | 0 | 55 |
Sum | 400 | 100 | 62 | 43 | 5 | 50 | 106 | 16 | 783 |
for both increasing the rate of soil fertility recovery, and providing more diverse habitats for wildlife [
As mentioned, Westham Island is located on the Pacific Flyway, in which the George C. Reifel Migratory Bird Sanctuary has been identified as a world-class
1995 | 2005 | 2015 | |
---|---|---|---|
Number of Fields | 16 | 26 | 35 |
Total Area (ha) | 242 | 209 | 292 |
Area per field (ha) | 15 | 8.0 | 8.4 |
migratory stopover for waterfowl to nest, breed and feed; it supports a large amount of wintering concentrations of migratory birds in Canada [
The value of wildlife habitat as an integrated ecosystem services provider by different land use and land cover types was presented in [
As an attempt to assess how [
In [
and with smaller areas of wild lands.
A comprehensive study of bird counts was conducted by [
With the implementation of the Winter Cover Crop Stewardship Program, there is evidence that cover crops planted in late fall or winter have provided a rich food source and shelter for wildlife, especially for herbivorous waterfowl, such as lesser snow geese, American wigeon, northern pintail, mallard and trumpeter swan [
In addition to providing direct food sources and nesting habitats, indirect benefits have been also gained from cover crops. Some species of waterfowl (e.g. Dunlin and Black-bellied plover) have been observed feeding on invertebrates on grazed cover crop fields [
Since grassland set-asides mimic the grasslands that were once abundant on the Lower Fraser River Delta prior to 1890 when land clearing and drainage networks for agriculture began, the set-asides provide ideal surrogate habitat for wildlife [
Group | Month | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
Loons | 4 | 4 | 2 | 1 | 0 | 0 | 0 | 0 | 1 | 1 | 2 | 1 |
Grebs | 171 | 275 | 233 | 326 | 1 | 1 | 1 | <1 | 2 | 118 | 288 | 117 |
Cormorants | 13 | 25 | 92 | 112 | 81 | 4 | 2 | 10 | 15 | 11 | 22 | 26 |
Canada Goose | 17 | 81 | 23 | 103 | 73 | 43 | 60 | 135 | 151 | 72 | 8 | 22 |
Dabblers | 1.648 | 7.139 | 5.397 | 3.257 | 449 | 189 | 172 | 728 | 2.420 | 703 | 393 | 390 |
Divers | 603 | 633 | 676 | 373 | 90 | 2 | <1 | <1 | 4 | 16 | 193 | 233 |
Mergansers | 153 | 120 | 206 | 203 | 34 | 4 | 7 | 1 | 17 | 19 | 30 | 58 |
Raptors | 22 | 19 | 11 | 7 | 6 | 3 | 6 | 5 | 11 | 13 | 21 | 27 |
Herons | 2 | 37 | 31 | 38 | 44 | 31 | 38 | 48 | 49 | 44 | 38 | 32 |
Coots | 82 | 80 | 67 | 91 | 6 | <1 | 0 | <1 | 12 | 26 | 26 | 20 |
Shorebirds | 940 | 2.014 | 74 | 536 | 155 | 40 | 298 | 229 | 270 | 544 | 1.069 | 459 |
Gulls | 7.307 | 11.674 | 9.348 | 7.134 | 10.159 | 984 | 1.372 | 4.146 | 13.328 | 16.635 | 14.004 | 6.436 |
Passerines | 184 | 334 | 238 | 306 | 479 | 641 | 630 | 523 | 260 | 189 | 221 | 257 |
Others | 5 | 5 | 4 | 568 | 41 | 72 | 115 | 103 | 190 | 199 | 59 | 5 |
Total | 11.176 | 22.440 | 16.402 | 13.055 | 11.618 | 2.014 | 2.701 | 5.928 | 16.730 | 18.590 | 16.374 | 8.083 |
Percentage | 7.70% | 15.50% | 11.30% | 9.00% | 8.00% | 1.40% | 1.90% | 4.10% | 11.50% | 12.80% | 11.30% | 5.60% |
Species | Population | Relative | Reference |
---|---|---|---|
estimates | Abundance (%) | ||
Trumpeter Swan | 125 | <0.1 | [ |
Tundra Swan | 125 | <0.1 | [ |
Greater Goose | 25 | <0.1 | [ |
Snow Goose | 40,000 | 13 | [ |
Brant | 4 500 | 1.5 | [ |
Canada Goose | 100 | <0.1 | [ |
Green-winged Teal | 50,000 | 16.3 | [ |
Mallard | 50,000 | 16.3 | [ |
Northern Pintail | 35,000 | 11.4 | [ |
Northern Shoveler | 100 | <0.1 | [ |
American Wigeon | 62,000 | 20.2 | [ |
Canvasback | 1600 | 0.5 | [ |
Scaup | 30,000 | 9.8 | [ |
Oldsquaw | 1200 | 0.4 | [ |
Scoters | 14,000 | 4.6 | [ |
Goldeneye | 1600 | 0.5 | [ |
Bufflehead | 5900 | 1.9 | [ |
Merganser | 1000 | 0.2 | [ |
Ruddy Duck | 9200 | 3 | [ |
There is concern that conventional agriculture has negative impacts on wild pollinator populations and biodiversity, due to habitat fragmentation and application of agrichemicals, for example [
In addition, grassland set-asides and crop rotations provide habitat for a diversity of pollinators, like bumblebees [
A common characteristic of the soils on Westham Island is their poorly drained conditions with relatively high water holding capacity and high organic matter content in the cultivated surface layer [
Grassland set-asides enhance soil structure, which is very important to sustain agricultural production [
Winter cover crops provide the ecosystem services of preventing rain-induced soil erosion, increasing soil organic matter, improving soil structure, increasing the water holding capacity, increasing the infiltration of water, fixing nitrogen and offsetting the need for commercial inorganic fertilizers. While directly improving soil health, cover crops also increase yields [
Improvements in habitat capacity of farmlands through the DF&WT Winter Cover Crop and Grassland Set-Aside Stewardship Programs has aided in maintaining the biodiversity of wildlife on Westham Island. This, in turn, may provide an indirect eco-tourism benefit to the area, as more tourists visit the Island to view wildlife.
Program | Ecosystem Services | Processes/Reasons | |
---|---|---|---|
Grassland Set-aside Stewardship Program | Water retention | Increase in water holding capacity | |
Drainage | Increase in soil macropores; the roots of grasses, especially clover, can bore channels through compacted soil | ||
Soil microbial activity, macro invertebrates | Increase in aeration | ||
Nutrient retention | Replenish soil organic matter | ||
Nitrogen Fixation | Plant cover that may decrease use of fertilizers | ||
Winter Cover Crop Stewardship Program | Prevent rain-induced soil erosion | Increase soil porosity and break up compaction by the roots | |
Nutrient retention | Cereal cover crops scavenge nutrients from leaching along with the heavy winter rains | ||
Nitrogen fixation | Plant clover cover that may decrease use of fertilizers | ||
Reduction in chemical controls | Cover crops can shade weeds and some release allelopathic compounds that inhibit weed growth |
Island. The George C. Reifel Migratory Bird Sanctuary consists of nearly 300 hectares of managed wetlands, natural marshes and low dykes at the northern end of the Island and has been reported to host over 70,000 visitors annually [
There are four farms on Westham Island which operate as tourism and recreation centers: Angel Estate Winery, Emma Lea Farms, Westham Island Herb Farm and Cropthorne Farm. Direct agricultural marketing is increasing and farm-related activities have been providing additional economic benefits, as well as diversifying farm operations [
An integrated assessment of the ecosystem goods and services on Westham Island demonstrated that enhanced ecosystem goods and services may be achieved by collaborative ventures focusing on the whole system, rather than solely through an agricultural production lens. Westham Island farmers participating in programs promoted by the DF & WT that incorporate grassland set-asides and winter cover crops have decreased potential conflict between sustaining wildlife habitat services and agricultural production. The management regimes are complementary and mutually beneficial, as agricultural crop rotations contribute to habitat for wildlife, especially waterfowl, and, soil quality has been maintained, providing benefits to agricultural production in the longer term.
The increase in diversity of cover crops and flower-rich plants has improved the potential for insect pollination, and this integration of agricultural production and pollination services has had a positive effect on wildlife habitat by providing additional food sources. These ecosystem services may have had an indirect impact on cultural services, such as eco- and agro-tourism, educational and aesthetic services. The implementation of the Grassland Set-Aside and Winter Cover Crop Stewardship Programs has also improved soil quality for maintaining and improving agricultural production as initiated by the DF&WT.
In order to provide for further development and assessment of ecosystem goods and services, the application of the “willingness-to-pay” to address some of the more qualitative services should be considered. The geographical setting of the study area encompasses important groundwater resources, intensive agriculture, and is located on an international bird flyway in a peri-urban environment; these qualities provide the opportunity to extend, through appropriate data collection, the assessment of additional provisions of ecosystem goods and services that include water management strategies to minimize increased salinity from irrigation, flooding and contamination of local water resources.
By the improvement in soil quality it is likely that carbon dioxide sequestration will also increase. The integrated collaborative framework on Westham Island could address concerns regarding carbon markets and offset programs, and how carbon sequestration and storage might be adapted to different management regimes [
Sincere thanks are expressed to the Delta Farmland and Wildlife Trust, Ducks Unlimited Canada, B.C. Ministry of Agriculture, Agriculture and Agri-Food Canada, and the Canadian Wildlife Service - Pacific and Yukon Region, for providing information for the study. A special note of thanks and gratitude to Christine Terpsma, former Program Coordinator of the Delta Farmland and Wildlife Trust, Delta, British Columbia.
This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
Zhang, Y., Wilson, J.E. and Lavkulich, L.M. (2017) Integration of Agriculture and Wildlife Ecosystem Services: A Case Study of Westham Island, British Columbia, Canada. Agricultural Sci- ences, 8, 409-425. https://doi.org/10.4236/as.2017.85031