Ecosystem Monitoring for Climate Change Adaptation

Forestry Resources

Forest (Planted): The LCBCCAP measures and monitors parameters including seedling survival, condition of seedlings and growth rate. There has also been strategies to implement fire management regimes and hence number and extent of fires are recorded to see the impact of the actions. Where trees are planted on river banks, wetland and agricultural land, the project monitors update of water in order to manage the trade-off between trees and water. Portable low-cost means for measuring tree water use has been developed by ICRAF and information on the kits is available at www.ictinternationa.com.au. Because of the potential of tree planting for carbon sequestration, the project conducted baseline surveys of carbon stocks before implementing any intervention. Where communities switched land use from carbon emitting to carbon sequestering land use change, the monitoring parameters were land-use characterization and calibrated estimates of time - average carbon stock associated with each land use. In order to reduce the risk of leakage, all activities were monitored for improvement in biodiversity and livelihood benefits (food, fuel, etc).


Existing Indigenous Forests: Baseline carbon stocks were measured at the beginning of the project to establish carbon credits under REDD using the Plan VIVO Carbon Management and Rural livelihoods scheme. Monitoring used the same mensuration techniques for planted woodlots to satisfy the requirements of maintaining the stocks. Since a certain percentage of the carbon is not sold as insurance against potential risk from fire and encroachment, monitoring has been necessary to ensure that loss if any is within the risk level. Also tree planting was used to provide alternative sources of wood and livelihoods. Other livelihoods activities includes beekeeping, mushroom growing, etc as identified through PRA. Monitoring the success of alternative livelihood activities is essential to safeguard the carbon stocks in the forests.

Land

Soil Erosion: Past studies (Jamu and Chimphamba, 2001) have shown that soil erosion is one of the major problems being faced in the Lake Chilwa Basin. Soil erosion rates are most severe ((>110 t.ha-1.yr-1))on the foot hills of the Zomba Mountain and these were due to a combination of steep slopes, poor vegetation cover and high kinetic energy of runoff. High soil erosion rates reduce crop yields, increase river sedimentation and negatively impact fish breeding and ultimately may impact fish production in Lake Chilwa. High river sediment yield and runoff may also affect the effectiveness of irrigation structures and cause floods which can negatively impact productivity of irrigation schemes and destroy infrastructure such as roads and bridges.


Soil erosion are monitored in the project using the Soil Loss Estimator for Southern Africa (SLEMSA). Soil loss is estimated in soil erosion management units (SEMU’s), a mapping unit of a homogeneous area brought about by a unique combination of the three sub models, topographic factors, soil erodability, and vegetation canopy cover used in the SLEMSA. This approach has been demonstrated in the Lake Chilwa basin to be useful and convenient in estimating soil loss and communicating impacts of soil erosion to communities and development practitioners


As a strategy for creating community awareness of the effects of different land use and management practices on soil loss, sediment collection pits have been constructed in selected SEMU’s located in mini-catchments within the basin hotspots. Thirty nine (39) sedimentation pits have been constructed in five Hotspots of the Lake Chilwa Basin Project and these are used to quantify soil erosion in the different hotspots. Quantification of weight of soil lost under different management regimes and agroecosystems is done in the hotspots. Communities have been trained to monitor soil loss from mini-catchments and maintain sediment pits. Mini-catchments have been selected to cover the range of management practices and land use degradation observed in the selected hotspots. Volunteers from within each village maintains the sedimentation collection pit as a community monitoring and awareness program. Field days have been conducted where results obtained from the sediment pits were discussed and used to revise or update action plans for reducing soil loss and improving the river ecosystem health.


Increased soil erosion losses, will increase sediment yields and hence siltation rates of the lake. Since river sediment load are difficult to monitor, sediment yield is a useful indicator of impact of soil erosion on river sediment load and water quality. Catchment sediment yields are obtained by using standard procedures.


Soil organic matter: Soil organic matter is the most important soil property. Organic matter provides a friable structure that enables effective water and air movement within the soil profile. Organic matter is also a nutrient store, the equivalent of a slow release fertilizer. Continuous ploughing exposes organic matter to oxygen and results in mineralization and hence loss of CO2 to the atmosphere hence the soil loses pore space that permits rainwater to infiltrate and to recharge aquifers. Burning, a common method for clearing crop fields, and harvesting of organic matter for other off-farm uses, reduces soil organic matter. The combined effect of these practices is release of CO2 previously sequestered in the organic matter, reduced water infiltration resulting in flash floods and poor yields. The release of CO2, a greenhouse gas, could significantly contribute to global warming and climate change. As such Soil organic matter is monitored by the programme using standard methods to monitor the impact of carbon sequestration mitigation strategies such as conservation agriculture and agroforestry in comparison to existing practices that do not enhance carbon sequestration

Water

Lake Chilwa water levels were monitored at Kachulu, Mposa, Namanja and Swang’oma gauging sites that have been in operation since January 2011


River discharge: Perennial river flows are important because they sustain livelihoods through irrigation, fishing and provision of potable water to urban and rural populations. The most important rivers in Lake Chilwa basin are Sombani, Namadzi, Likangala, Thondwe, Domasi and Phalombe Rivers which discharge water to Lake Chilwa and the wetlands. These rivers are very important because they sustain livelihoods in the whole basin through small scale irrigation, fishing, and aquaculture and provide portable water to both rural and urban populations. Discharge of these rivers is monitored regularly by the programme. Deforestation of forest reserves and river courses have disturbed the hydrological cycle by increasing runoff and reducing recharge of groundwater aquifers. Similarly, bad agricultural management practices enhance runoff and reduce water infiltration. Discharge in hotspot rivers is monitored to assess impact of climate change adaptations using flow meters. Data collected from non-hotspots is used as control to compare adoption of climate change interventions versus non-adoption. To ensure sustainability, the project works with the Water Department to revamp the river flow/flood monitoring system in the basin.

Fisheries

Fish landings, sales and prices area monitored on a daily basis through beach village committees using participatory approaches. The number of fishing craft, gear owners, crew members and fishing gears are monitored annually using frame surveys. The information collected is used to monitor the impacts of adaptation strategies on fish production and marketing and will assist in the adaptation of existing area-based management plans. Changes in diversity of lake species which use rivers to breed is also monitored twice a year using established ecological procedures to determine the effectiveness of programs in hotspots to promote recovery and enhance productivity of fisheries. Data collection using the simplified fish catch data monitoring and recording system using log books by BVC members has been developed and is operational by the programme.