|Main authors:||Susanne Klages, Claudia Heidecke|
|Source document:||»Hasler, B. et al. (2021) Identification of cost-effective and coherent management models for drinking water protection in agriculture. FAIRWAY Project Deliverable 6.4R 55 pp|
The assessment of pesticide and nitrate abatement measures used for the protection of drinking water from both surface and groundwater sources is one of FAIRWAY's research themes. For details of the methodology used for the assessment, an in-depth analysis of catch crops (a measure often used for nitrate abatement), and the general conclusion drawn from this and other case studies see »Cost-effective and coherent management models for drinking water protection.
|2. Catch crop schemes in Germany|
|3. Farmers' current perceptions of motivations and challenges for implementing catch crops|
Lower Saxony is an intensely farmed federal state in the north of Germany with 1.562.097 ha of arable land (2016). In the past, water protection was implemented by regulatory laws and activities individual water works. With the 8th amendment of the Lower Saxony Water Act (NWG)
- The Lower Saxony cooperation model was introduced in 1992. Coordination unit is the Lower Saxony Water Management, Coastal Defence and Nature Conservation Agency (NLWKN) (Quirin, 2011)
- The Cooperation model is limited to water protection and water abstraction areas as defined according to NWG. In 1994, in the cooperation area the total area with catch crops was 10,500 ha and increased until 2016 to 40,634 ha.
For the whole territory of Lower Saxony, in 1999, total area of winter catch crops amounted to 78,159 ha, while summer catch crops were grown on 71,797 ha.
Catch crop cultivation stagnated over the first decade after the millennium. In 2010 however, there was a sharp increase in winter catch crop cultivation, now amounting to 206, 927 ha, while summer catch crop cultivation further stagnated. Within the cooperation area, it is coordinated by NLWKN. A new AEM scheme named PFEIL was introduced in 2014. From 2015 onwards, there was another sharp increase of catch crop cultivation in Lower Saxony, due to the introduction of the Greening of the CAP: in 2016, 348,620 ha of winter catch crops were cultivated, the area of summer catch crops slightly decrease to 68,780 ha. In 2021, due to the recent and stricter national implementation of the Nitrates Directive with a revision of the fertilization ordinance, a further increase of the winter catch crop cultivation area is expected.
At present, there are four schemes promoting the cultivation of catch crops, which are not all coordinated with each other.
1. Ecological Focus Area (EFA) catch crops (pillar I/basic payment scheme of CAP).
If the farmer has an area (arable land) larger than 15 ha (not required for organic producers), then 5 percent of the area has to be EFA. Here catch crops are one out of many measures that farmers can use (count 1/3). (In 2016, catch crops as ecological focus area was cultivated on 223,774 ha (subsidy of 75 €/ha), additional 37,559 ha of under sown catch crops (subsidy of 120 €/ha). This is a share of ca. 75 % of all ecological priority areas in Lower.
2. AES catch crops (pillar II of CAP)
In the funding period 2014-2020, Lower Saxony (and Bremen as city state), supported via pillar II (PFEIL-program) among other AES winter hardy catch crops and under sown catch crops (implementation rate relatively small, < 10 % of the total UAA).
3. Mandatory catch crops.
Farms in NVZ are from 2020 obliged to cover the soil of arable land during the winter season (in case precipitation is > 550 mm/year), according to the latest amendment of national Fertilization Ordinance, as national implementation of the ND (implementation rate to be estimated; NVZ ca. 39% of the UAA, ca. 1 Mio. ha).
4. Voluntary schemes as part of the farmer-drinking waterworks cooperation.
Lower Saxony Water Act (NWG): It authorises water authorities to define water protection zones by decree/ordinance. Water authorities are entitled to determine protective provisions. This includes how the land in the protection zones is cultivated. The ministry in charge may adopt protective provisions for one or more protection zones. In case a protective provision narrows the agricultural/silvicultural/horticultural use of land or leads to additional costs, a financial compensation has to be paid. Exclusively for these water protection zones, a guideline for compensation payment is published yearly by LWK Lower-Saxony (and financed by the Lower Saxony Ministry of Environment from a water extraction fee) (Chamber of Agriculture Lower Saxony, 2019).. In 2016, 74 cooperation in 374 drinking water abstraction areas were organized covering 293,000 hectare land with agricultural use which equals 11 % of the total UAA, and 239,000 ha wooded land (Quirin and Hoetmer, 2019)4. This is larger than the actual water protection zones, as they are also including registered drinking water abstraction zones (152,610 ha). Current maximum subsidy in 2016 for catch crops amounts to 249 €/ha, average 100 €/ha; area with catch crops was 40.634 ha).
In arable crop production, catch crops can easily be integrated in the usual cropping patterns and practices (Hart et al. 2016). This is at least the case in the Greening-schemes were the share for mandatory catch crops is with 15% of the UAA (catch crops “count” 1/3) reasonably small.
- If total yearly precipitation is low < 550 mm (DüV, 2020), the water consumption of the catch crop and of main crop will be competing.
- Catch crops produce additional organic soil matter in autumn which will store additional water for main crop in spring; according to field trials in Austria in ca. 80 % no difference is noticed between cultures with/without catch crop (Lütke-Entrup, N. et al., 2018).
- Dry seedbed in autumn will result in low germination rate. Humid conditions in autumn will result in no soil preparation and seedbed preparation possible. Under both of these conditions only under sowing of catch crop in the main crop is possible.
- Short vegetation period after harvest results in no establishment of catch crop.
- Long vegetation period after harvest results in strong establishment of catch crop, and this might provide challenges related to seed preparation.
- No frost in winter can result in green catch crop in spring, resulting in problems with seedbed preparation.
- Strong winter hardy catch crop can result in necessity of special soil cultivation (e.g. disc harrow)
For full references to papers quoted in this article see