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Article

Effects of Two Management Practices on Monthly Litterfall in a Cypress Plantation

by
Yulian Yang
1,
Honglin Yang
1,
Qiang Wang
1,
Qing Dong
1,
Jiaping Yang
1,
Lijun Wu
1,
Chengming You
1,2,
Jinyao Hu
1 and
Qinggui Wu
1,*
1
Ecological Security and Protection Key Laboratory of Sichuan Province, Mianyang Normal University, Mianyang 621000, China
2
Forestry Ecological Engineering in the Upper Reaches of the Yangtze River Key Laboratory of Sichuan Province & National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River & Rainy Area of West China Plantation Ecosystem Permanent Scientific Research Base, Institute of Ecology & Forestry, Sichuan Agricultural University, Chengdu 611130, China
*
Author to whom correspondence should be addressed.
Forests 2022, 13(10), 1581; https://doi.org/10.3390/f13101581
Submission received: 30 August 2022 / Revised: 20 September 2022 / Accepted: 23 September 2022 / Published: 27 September 2022
(This article belongs to the Special Issue Carbon and Nutrient Transfer via Above and Belowground Litter in Forests)
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Abstract

:
Optimizing stand structure can enhance plantation forest ecosystem service functions by regulating litterfall patterns; however, the effects of close-to-nature management on litterfall production remain unclear. Here, we selected three cypress (Cupressus funebris) plantations, including one using the practice of strip filling (SF), one using the practice of ecological thinning (ET), and one pure cypress plantation without any artificial interference. The production of total litterfall and its components (leaf, twig, reproductive organ and miscellaneous litterfall) were investigated monthly over one year from September 2019 to August 2020. Compared with that of the pure plantation, the total annual litterfall production of the SF and ET plantations decreased significantly by 10.8% and 36.44%, respectively. The annual production of leaf and reproductive organ litter was similar to that of total litterfall, but that of twig and miscellaneous litter was higher in the SF and ET plantations than in the pure plantation. Moreover, total, leaf and reproductive organ litterfall production displayed unimodal dynamics regardless of plantation, although the peaks of reproductive organ litter production occurred in different months. In contrast, the production of twig litter showed bimodal dynamics in the pure plantation, while unimodal and irregular dynamics were observed in the plantations with ET and SF, respectively. Additionally, insignificant differences in the isometric growth index of leaf litter and total litterfall were observed. The allometric indices of twig litterfall versus total litterfall, reproductive organ litterfall versus total litterfall, and leaf litterfall versus twig litterfall were higher in the plantations with SF and ET than in the pure plantation. Redundancy analysis (RDA) revealed that diameter at breast height and air temperature were the most important factors shaping the annual and monthly production of litterfall, respectively. These results provide efficient data to support the rectification of the material circulation of cypress plantations and their future management.

1. Introduction

The global area of plantation forests exceeds 2.84 hundred million hm2, with plantation forests in China showing the largest area and fastest development worldwide [1]. Many ecological problems occur with the development of plantations [2,3]; thus, close-to-nature management (actively or passively developing planted forest communities into more diverse vegetation communities dominated by native species) has recently been used to maintain and improve ecosystem ecological function and stability [4,5,6,7]. Indeed, many previous studies have demonstrated that plantation management practices (e.g., thinning, strip-cutting, introducing tree species) have increased the diversity of forest species and improved soil properties [8,9,10,11]. However, the mechanisms driving the improvement of these ecological functions involved in management practices remain unclear.
Litterfall is one of the major pathways by which organic matter and nutrients return to soils from vegetation [12,13], and the production and patterns of litterfall significantly contribute to the maintenance of soil fertility and nutrient balance in forest ecosystems [14,15]. Its production and its temporal dynamics are strongly influenced by tree density, vegetation composition and climate factors (e.g., temperature, precipitation, wind etc.) [16,17,18], which are significantly regulated by management practices [19,20]. For instance, thinning or strip-cutting can primarily reduce stand density or canopy density. The decrease in stand density or canopy density not only directly reduces total litter production but also indirectly alters the composition of litterfall by affecting the formation and regeneration of light-loving vegetation [8,21]. In contrast, replanting or reconstruction in mixed forests could directly change the composition of litterfall as a result of adding new species. The practices mentioned above can all make the monthly production of litterfall vary. Since the production of litterfall is higher in mixed stands or species-rich forests than it is in monocultures [22,23,24], we hypothesized that forest management practices that increase species richness might be more conducive to litter production. However, although some studies have reported the characteristics of litterfall production at different levels under certain management practices [25,26], it is difficult to accurately predict litterfall among these practices, which is not conducive to comprehensively understanding the mechanism of litterfall among management practices.
In general, litterfall composed of materials from different organs exhibits allometric relationships [27,28]. The allometric relationship of litterfall production provides a new approach for estimating forest productivity because litterfall is an important contributor to the net primary productivity of forest ecosystems [29]. However, the biomass allocation in litterfall is still under debate. For instance, Ma et al. [27] found that the allometric relationships between total litterfall and litterfall components were approximately the same in evergreen forests and deciduous forests in China. However, Fu et al. [28] found that the allometric relationships of forest litterfall varied with litterfall components, functional types and vertical structures in alpine forests, e.g., evergreen versus deciduous and trees versus shrubs. Thus, additional studies on the allometric relationships of forest litterfall in different climatic zones, at different regional scales and in various forest types are needed. The management practice of plantations, as a form of human disturbance, inevitably create heterogeneous habitats and are expected to affect the allocation of litterfall from different organs.
As one of the major tree species in the Yangtze River shelter forests, cypress (Cupressus funebris) plays a critical role in regulating the regional climate and conserving water and soil. Cypress plantations have also led to a weak capacity for water storage, low biodiversity, and soil degradation, resulting in a large decrease in ecological services, although they have addressed the demand for high forest coverage. Therefore, a series of experiments implementing forms of management practices, such as strip filling (first strip-cutting and then replanting) and ecological thinning, were performed to adjust the structure of cypress plantation monocultures and improve their ecological functions. Although the water-holding capacity, plant diversity, soil microbial diversity and physicochemical properties after implementation of several management practices have been widely reported [30,31,32,33], little attention has been given to litterfall production. Here, a one-year field study, implementing the litter trap method, was carried out on three cypress plantations, including two management practices (strip filling and ecological thinning) and an unmodified pure plantation for comparison. Litter production was investigated monthly to assess the changes in annual total litterfall production and seasonal dynamics, as well as the allometric growth relationships among litter organs under different management practices. Specifically, we hypothesized that (1) the total litterfall production and its components would be higher in the plantation with management practices than in the pure cypress plantation and (2) management practices would alter the monthly dynamics of litterfall and change the allometric relationships in cypress plantations.

2. Materials and Methods

2.1. Study Area

This study was conducted in Linshan Township, Yanting County (105°45′ E, 31°27′ N), located in the hilly area of the central Sichuan Basin, China. This region has typical low hill landforms with elevations of 400 m to 650 m. The climate is a subtropical monsoon climate, and the mean annual temperature and precipitation during 2008–2019 were 17.3 °C and 826 mm, respectively. This region is rich in purple shale that is easily weathered, and the soils are primarily purple soils. The aboveground vegetation is dominated by cypress plantations which were planted at a density of 4000–6000 plants/hm2 in the 1970s. However, due to the high initial planting density and lack of necessary management, the ecological functioning of the plantation was in a degraded state, and the stand structure urgently needed adjustment.

2.2. Experimental Design

From 2005 to 2008, pure cypress plantations with similar aspects, slopes, and altitudes were selected for management experiments, including strip filling and ecological thinning practices. In the strip filling practice, after forming a series of 4–10 m bandwidths through artificial logging, native broadleaved tree species, such as Alnus cremastogyne and Camptotheca acuminata, were replanted for striping mixing. In comparison, the ecological thinning practice involved randomly cutting down part of the cypress trees with a removal of 10%–25% of the initial basal area. Meanwhile, the logging residues under both practices were removed from the experimental areas. Previous studies have found that there is a better ecological effect (e.g., high plant diversity and soil nutrient content) in the pattern of strip filling with a bandwidth of 6 m and in the pattern of ecological thinning with a thinning intensity of 20%–25% [33,34]. Accordingly, in the present study, we intended to further study the characteristics of litterfall under these two patterns.
In August 2019, five replicate plots (20 × 20 m in size and 50 m apart) were established in plantations with strip filling, ecological thinning and no artificial interference (pure forest), respectively. The stand characteristics of the three sampling plantations in 2019 are listed in Table S1. The meteorological data (wind speed, precipitation, temperature and relative humidity) from the Yanting Agro-ecological Station of Purple Soil, Chinese Academy of Sciences, from 2019 to 2020, are shown in Figure S1.

2.3. Litter Collection

Six litter traps (1 × 1 m in size and 50 cm above the ground) made of nylon materials with a mesh size of 1 mm were distributed randomly in each plot for the three plantations. Specifically, in the strip filling practice, six litter traps were placed equally within the strip cutting area and an adjacent uncut area. Litterfall was collected approximately monthly from September 2019 to August 2020. These monthly subsamples were pooled to create composite three-month samples in approximately the early dry season (January–March), late dry season (April–June), early wet season (July–September) and late wet season (October–December), according to the tropical forest division [15] and previous climatic data for the region. All litter materials were classified as leaf litter (including broad leaf and needle leaf litter), twig litter (including bark), reproductive organ litter (including flower, fruit and seed litter) and miscellaneous litter (unidentified components, such as indistinguishable detritus, dead animals and insect excrement). All litter materials were oven-dried separately at 65 °C, and the total litterfall was calculated as the sum of the dry litter mass for all litter components.

2.4. Statistical Analyses

Repeated-measures analysis of variance (ANOVA) was employed to test for effects of sampling time and plantation on litterfall production. One-way ANOVA with Tukey’s honestly significant difference (HSD) test was used to test for the effect of plantation or season on litterfall production and the proportion of each litter component relative to total litterfall. Meanwhile, to calculate the relative influence of each factor, we employed redundancy analysis (RDA), using the ”vegan” package, and hierarchical partitioning analysis using the “rdacca.hp” package in R [35]. Considering the consistency of the climate in each plantation and little within-year variation in vegetation factors, we analyzed the relative effects of vegetation factors on annual litterfall production and climate factors on monthly litterfall production. All statistical analyses were performed using R 4.0.5 (R Core Team 2021).
The allometric approach was used to analyze annual litterfall production, which was expressed as Y = β Xα or logY = α log X + log β, where X and Y represent the total litterfall production and its different components (leaf, twig and reproductive organ litterfall) of each planation, respectively; α is the regression slope (scaling exponent); and β is the regression intercept. When the 95% confidence interval contained 1, α indicated that the scaling relationship between Y and X was isometric; otherwise, the relationship was interpreted as allometric [36].
After we log10-transformed the litterfall production data, a model II regression method (i.e., reduced major axis regression, RMA) was applied to estimate the regression parameters and test whether the slopes were significantly different from 1, as well as different among the plantations [37]. When the slopes for the different plantations did not differ significantly, a common slope was first provided, and then the Wald test was performed to test whether there were intercept or coaxial drifts between plantations. The model II regression analysis was performed in SMATR Version 2.0.

3. Results

3.1. Annual Litterfall Production

The annual total litter production and its components showed significant differences among the plantations (p < 0.05). The total annual litterfall production in plantations with strip filling (3672.46 kg·ha−2, SF) and ecological thinning (2617.67 kg·ha−2, ET) was significantly decreased by 10.8% and 36.44%, respectively, compared with that in the pure cypress plantation (4118.01 kg·ha−2, PC) (Figure 1a). Similarly, both reconstruction treatments decreased the annual production of leaf and reproductive organ litter, and the greatest declines were observed in the plantation with ET (Figure 1b,d). In contrast, both reconstruction treatments increased the annual production of twig and miscellaneous litter, and a significant difference was observed only between the plantation with SF and the pure plantation (Figure 1c,e).
The proportion of each litter component relative to the annual total litterfall (except the reproductive organ litter) showed significant differences among the three plantations (p < 0.05). In general, leaves accounted for more than 80% of the annual total litterfall in the three plantations (Figure 2). Compared with the pure plantation, both reconstruction treatments significantly decreased the proportion of leaf litter relative to total litterfall and increased the proportion of twig and miscellaneous litter relative to total litterfall (Figure 2). Moreover, there were no significant differences in the proportions of leaf, twig and miscellaneous litter between the plantations with SF and ET (p > 0.05).

3.2. Monthly Dynamics of Litterfall

Litterfall varied monthly, and this variation showed different patterns among plantations and litter components (Table S2, Figure 3). Regardless of the plantation, the production of total litter and leaf litter displayed unimodal dynamics, with the peak occurring in May (Figure 3a,b). Meanwhile, more than 70% of the total litterfall and leaf litterfall occurred during the late dry season (from April to June) and early wet season (from July to September) in each plantation, taking the rank order of pure cypress plantation > plantation with SF > plantation with ET (Figure 4a,b). However, the production of total litter and leaf litter in plantations with SF was obviously higher than that in the other two plantations during the late wet season (from October to December) and early dry season (from January to March).
The production of twig litter showed a major peak in August and a smaller peak in April in the pure plantation. In contrast, it only peaked in May in the plantation with EF and had no clear pattern in the plantation with SF (Figure 3c). Meanwhile, more than 45% of the twig litter in the pure plantation occurred during the late dry season, while litter in the plantation with EF occurred during the early wet season. However, the production of twig litter in the plantation with ET was significantly higher than that in the pure cypress plantation (Figure 4c).
Moreover, the production of reproductive organ litter in the three plantations was unimodal, with the peaks in the pure, SF and ET plantations occurring in August, June and May, respectively (Figure 3d). In addition, it was highest in the plantation with SF and in the pure plantation during the dry and wet seasons, respectively (Figure 4d).
The production of miscellaneous litter was unimodal in the pure plantation, with the peak occurring in August, while it showed a major peak in August and a smaller peak in May, regardless of whether plantations used SF or ET (Figure 3e). For all seasons, the production of miscellaneous litter in plantations with SF was obviously higher than that in the other two plantations (Figure 4e).

3.3. Allometric Scaling Relationships of Annual Litterfall

Regardless of the plantation, significant isometric relationships were observed between leaf litterfall and total litterfall, while allometric relationships were observed for annual twig litterfall versus total litterfall and reproductive organ litterfall versus total litterfall (Table 1, Figure 5). The scaling slopes of leaf litterfall versus total litterfall in the different plantations did not differ significantly, with a common slope of 1.020. According to the Wald test, however, the intercept and coaxial drifts showed significant differences among the three plantations (Figure 5). Moreover, the scaling slopes of twig litterfall versus total litterfall in the plantation with ET and reproductive organ litterfall versus total litterfall in the plantations with SF and ET were significantly higher than those in the pure plantation.
Significant allometric relationships were observed for leaf litterfall versus twig litterfall in different plantations, and the scaling slope in the plantation with ET was significantly higher than that in the pure plantation (Table 1, Figure 5). Meanwhile, significant allometric relationships were observed for leaf litterfall versus reproductive organ litterfall in the plantations with SF and ET. Moreover, for twig litterfall and reproductive organ litterfall, a significant positive allometric relationship was observed in the plantation with SF, while an isometric relationship was observed in the plantation with ET. However, the relationships of leaf litterfall versus reproductive organ litterfall and twig litterfall versus reproductive organ litterfall in the pure plantation could not be expressed by allometric equations.

3.4. Factors Driving the Changes in Litterfall Production

RDA revealed that vegetation factors explained 62.40% of the variation in annual litterfall production (Figure 6a). Annual total litter, leaf litter and reproductive organ litter all showed high production under conditions of lower diameter at breast height and tree height. Annual twig litter and miscellaneous litter showed high production under conditions of higher species richness and lower stand density and canopy density. Meanwhile, hierarchical partitioning analysis showed that diameter at breast height and tree height were the most important factors (p < 0.05), explaining 17.85% and 16.14% of the variation, respectively (Table 2).
The climate factors explained 46.84% of the variation in monthly litterfall production (Figure 6b). Monthly total litter, leaf litter and twig litter all showed high production under conditions of higher mean wind speed and lower relative humidity. Monthly reproductive organ litter and miscellaneous litter showed high production under conditions of higher precipitation and air temperature. Meanwhile, in terms of the degree of influence on monthly litterfall production (p < 0.05), the climate factors ranked as follows: air temperature (16.38%) > relative humidity (15.95%) > mean wind speed (9.09%) > precipitation (5.41%) (Table 2).

4. Discussion

4.1. Annual Litter Production

Forest litterfall is strongly influenced by stand density, plant composition and tree age for a similar climate scenario [17,38,39]. In the present study, we observed that annual total litterfall production ranged from 2617.67 to 4118.01 kg·hm−2 in different plantations (Figure 1a), which was within the range of tropical and subtropical needle-leaved evergreen forests (531–10523 kg·hm−2) [40]. Meanwhile, we observed that the annual production of total litterfall across the plantations exhibited the following order: pure plantation > plantation with SF > plantation with ET (Figure 1a). In general, for stand level, litterfall production increased with increasing stand density [18,39]. Accordingly, the decreased stand density in plantations with SF and ET may directly lead to decrease in litterfall. However, the variation pattern in total litter production among the investigated plantations was not consistent with their changes in tree density (Figure 6a). Bray and Gorham [41] first showed that litter production appears to be little affected by differences in plant density within closed-canopy forests, and some other studies exhibiting plantation management practices with the main purpose of reducing stand density also concluded that there was no change or significant increase in the production of litterfall [42,43]. Based on these findings the variation pattern may be related to differences in species richness caused by different management practices and the time lapse after management. In addition, the plantation with SF (lower stand density but higher species richness) showed higher total litterfall than the plantation with ET (higher stand density but lower species richness) in our study, which was consistent with previous studies suggesting that mixed plantations had higher litterfall production than pure plantations [24]. Although the trend of leaf litterfall was consistent with that of total litterfall, the proportion of broadleaf to total leaf litterfall in the plantation with SF (19.12%) was higher than that in the plantation with ET (4.57%) (Figure S2), which also suggested that the leaf litter produced by artificial replanting of broad-leaved species was more abundant than that produced by natural succession within the same time period after management. This result further indicated that the plantation with SF was more conducive to increasing the species diversity of litter, thus forming different carbon and nutrient cycling patterns. Similarly, the production of twig litterfall in the plantations with SF and ET was higher than that in the pure plantation. A likely explanation is that it was positively correlated with species richness (Figure 6a).
Consistent with many previous studies [17,20,28], we found that the production of litterfall in the three plantations was dominated by leaf litter, which emphasized the key role of leaf litter in material circulation and energy flow in cypress plantations. However, we also found that both management practices significantly decreased the proportion of leaf litter relative to total litterfall and increased the proportion of twig and miscellaneous litter relative to total litterfall (Figure 2). Our findings therefore suggest that the responses of production to forest management practices varied with the litter components. Additionally, although our study lasted one year, the reduction in leaf litterfall proportion provided a new approach to explore the material-related mechanisms of management practices, as the stand structure of cypress plantations is relatively stable after 11 years of management.

4.2. Litterfall Monthly Dynamics

The monthly dynamics of litterfall were unimodal and bimodal, which mainly depended on the climatic conditions and ecological characteristics of the tree species [40,44,45]. Therefore, the differences in canopy density and species composition under different forest management practices may result in different monthly variation characteristics of litterfall. However, many previous studies have suggested that these management practices (thinning, prescribed burning) did not alter the monthly dynamics of leaf litterfall [42,43]. Consistent with previous findings, we observed that the production of leaf litterfall showed unimodal dynamics, with the peak occurring in May in the three plantations, and reasonable explanations for this result might be as follows: (1) cypress was dominant in the three plantations, and the shedding time of old leaves was relatively concentrated. (2) The climate factors significantly influenced the intra-annual litterfall dynamics [16,46]. The obvious positive correlation between leaf litterfall and wind speed in Figure 6b could also confirm this; therefore, the higher wind speed in May might have led to the high production of leaf litterfall. Meanwhile, the production of total litterfall was controlled by leaf litter; therefore, the monthly dynamics of total litter and leaf litter were similar.
Unlike the leaf litter, we found different monthly dynamic patterns of twig litter, reproductive organ litter and miscellaneous litter in the three plantations. Previous studies showed that the monthly collected twig litterfall that came from dead branches was less directly affected by phenology but was sensitive to climatic factors, such as wind speed and rainfall [45,46]. Therefore, plantations with different management practices can vary in their response to such climate factors and, thus, result in distinct monthly dynamic patterns of twig litter. In general, the shedding time of reproductive organs varies among species, but temperature, wind speed and rainfall could also alter the characteristics of litterfall [46,47]. Therefore, although the production of reproductive organ litterfall showed unimodal dynamics in the three plantations, its peak of production could occur in different months. Nevertheless, there was no uniform pattern in the monthly dynamic changes in miscellaneous litter among different plantations resulting from the relatively complex components, although it was positively correlated with rainfall and air temperature (Figure 6b). Interestingly, we found that the production of leaf litter and reproductive organ litter was significantly higher in the early dry season and lower in the wet dry season than in the pure plantation (Figure 4). Since different plant species have different litterfall production rhythms (e.g., conifers and broadleaved trees) [15], plantations with the highest species richness are more likely to show opposite seasonal trends. Overall, based on the one-year study, we highlight the importance of using monthly or seasonal variations in litter input and subsequent decomposition to explore the effects of plantation management practices on material cycling and energy flows in ecosystems.

4.3. Litter Components and Allometric Scaling Relationships of Litterfall

Variations in species, environmental gradients, human disturbances and other factors would lead to the self-regulation of resource allocation in plants, which would be reflected by different survival strategies [48,49,50]. Consistent with our expectations, the effects of reconstruction management on the relationships between each litter component and the total litterfall, as well as between litter components, were related to the reconstruction treatments (Table 1, Figure 5). Leaf litterfall and total litterfall showed an isometric relationship in the three plantations, which was in agreement with the results of Ma et al. [27] and Fu et al. [28], and this might be because leaf litter was the major component (more than 80% of the total litterfall production) (Figure 2). The Wald test revealed that the differences between the intercept and coaxial drifts were significant, although there were no significant differences in scaling exponents among the three plantations, and this result indicated that the isometric growth trajectories of leaf litterfall and total litterfall were not completely consistent in the three plantations. Furthermore, the allometric scaling exponents of twig litterfall and total litterfall in the plantation with ET were significantly higher than those in the plantation with ST and the pure plantation, which suggested that within a certain range of total litterfall, the plantation with ET allocated more production to twig litter. Similarly, the plantations with reconstruction allocated more production to reproductive organ litter than the pure plantation. More reproductive organ litterfall is preferred for breeding populations [51]; therefore, this result could explain the high vegetation diversity in plantations with reconstruction treatments.
Leaves are important photosynthetic organs, and the presence of more leaves accelerates the transport of nutrients from aboveground to belowground, thus promoting plant growth [49]. In this study, the allometric scaling exponent between leaf litterfall and twig litterfall in the plantation with ET was significantly higher than that in the plantation with ST and the pure plantation (Figure 5, Table 1), which suggested that within a certain range of twig litterfall, the plantation with ET allocated less production to leaf litterfall. This result further indicated that the plantation with SF might be superior to that with ET only from the perspective of plant growth. In addition, consistent with previous studies [28], we observed that some relationships (leaf litterfall versus reproductive organ litterfall and twig litterfall versus reproductive organ litterfall) could not be expressed by allometric equations in the pure plantation (Table 1), which may be related to reproductive organ litterfall being controlled by complex micrometeorological factors [51]. Unlike in the pure plantation, significant differences in relative growth slopes between the plantations with management practices were observed. These disparate responses further emphasized that cypress plantations could modify resource allocation to organs through physiological integration after intense disturbance and that those allocations were similar to disturbance patterns.

5. Conclusions

In this study, we explored the effects of strip filling and ecological thinning on the litterfall production and monthly dynamics of cypress plantations. In contrast with our hypothesis, both management practices significantly reduced the annual production of total litter, leaf litter and reproductive organ litter, and only strip filling significantly increased twig litterfall and miscellaneous litterfall. Nevertheless, management practices obviously changed the monthly dynamic patterns of twig litterfall, reproductive organ litterfall and miscellaneous litterfall but had few effects on total litterfall and leaf litterfall. Furthermore, the dominant factors affecting annual and monthly litterfall production were diameter at breast height and wind speed, respectively. These results confirmed the significant responses of litterfall production to management practices in cypress plantations, but the investigation remains limited in terms of management time and study continuity. There is a high need to further integrate carbon and nutrient inputs, address their cycling processes, and accurately evaluate the effects of strip filling and ecological thinning via long-term continuous research. Even so, the results presented here provide a primary reference for exploring the material mechanism by which management practices affect cypress plantations.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/f13101581/s1, Figure S1: Monthly average wind speed, air temperature, relative humidity and total precipitation during the study period; Figure S2: The proportion of broad leaf and needle leaf to total leaf litterfall in different plantations; Table S1: General descriptions of different plantations in the study site; Table S2: Repeated-measures ANOVA results for the responses of litterfall production to sampling time and plantations.

Author Contributions

Conceptualization, Q.W. (Qinggui Wu), Y.Y., C.Y. and J.H.; investigation, L.W., H.Y. and Q.W. (Qiang Wang); formal analysis, Y.Y., H.Y. and C.Y.; visualization, H.Y., Y.Y. and C.Y.; writing—original draft preparation, L.W., H.Y. and Y.Y.; writing—review and editing, Y.Y., J.Y., Q.D. and Q.W. (Qinggui Wu); funding acquisition, Q.W. (Qinggui Wu), C.Y., Y.Y. and Q.D. All authors have read and agreed to the published version of the manuscript.

Funding

This research was supported by the National Natural Science Foundation of China (32071747), the National Natural Science Foundation of Sichuan Province (2022NSFSC0087, 2022NSFSC1173), the Open Fund of Ecological Security and Protection Key Laboratory of Sichuan Province, Mianyang Normal University (ESP2203) and the Research Fund of Mianyang Normal University (QD2020A18).

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Not applicable.

Acknowledgments

We are grateful to the Ecological Security and Protection Key Laboratory of Sichuan Province.

Conflicts of Interest

The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

References

  1. FAO. Global Forest Resources Assessment 2020: Main Report; FAO: Rome, Italy, 2020. [Google Scholar]
  2. Liu, S.; Yang, Y.; Wang, H. Development strategy and management countermeasures of planted forests in China: Transforming from timber-centered single objective management towards multi-purpose management for enhancing quality and benefits of ecosystem services. Acta Ecol. Sin. 2018, 38, 1–10, (In Chinese with English Abstract). [Google Scholar]
  3. Zhou, Q.; Li, F.; Cai, X.; Rao, X.; Zhou, L.; Liu, Z.; Lin, Y.; Fu, S. Survivorship of plant species from soil seedbank after translocation from subtropical natural forests to plantation forests. For. Ecol. Manag. 2019, 432, 741–747. [Google Scholar] [CrossRef]
  4. Sujii, P.S.; Schwarcz, K.D.; Grando, C.; de Aguiar Silvestre, E.; Mori, G.M.; Brancalion, P.H.S.; Zucchi, M.I. Recovery of genetic diversity levels of a Neotropical tree in Atlantic Forest restoration plantations. Biol. Conserv. 2017, 211, 110–116. [Google Scholar] [CrossRef]
  5. Mohler, C.; Bataineh, M.; Bragg, D.C.; Ficklin, R.; Pelkki, M.; Olson, M. Long-term effects of group opening size and site preparation method on gap-cohort development in a temperate mixedwood forest. For. Ecol. Manag. 2021, 48, 118616. [Google Scholar] [CrossRef]
  6. Hou, L.; Zhang, Y.; Li, Z.; Shao, G.; Song, L.; Sun, Q. Comparison of soil properties, understory vegetation species diversities and soil microbial diversities between Chinese Fir plantation and close-to-natural forest. Forests 2021, 12, 632. [Google Scholar] [CrossRef]
  7. Hua, F.; Bruijnzeel, L.A.; Meli, P.; Martin, P.A.; Zhang, J.; Nakagawa, S.; Miao, X.; Wang, W.; McEvoy, C.; Peña-Arancibia, J.L.; et al. The biodiversity and ecosystem service contributions and trade-offs of forest restoration approaches. Science 2022, 376, 839–844. [Google Scholar] [CrossRef]
  8. Li, X.; Li, Y.; Zhang, J.; Peng, S.; Chen, Y.; Cao, Y. The effects of forest thinning on understory diversity in China: A meta-analysis. Land Degrad. Dev. 2020, 31, 1225–1240. [Google Scholar] [CrossRef]
  9. Felton, A.; Lindbladh, M.; Brunet, J.; Fritz, Ö. Replacing coniferous monocultures with mixed-species production stands: An assessment of the potential benefits for forest biodiversity in northern Europe. For. Ecol. Manag. 2010, 260, 939–947. [Google Scholar] [CrossRef]
  10. Bei, P.; Si, S.; Zhou, D.; Chen, J.; Zhao, R.; Mu, C. Effects of strip reform on understory plant diversity of Cupressus funebris plantations in Hilly Areas of Central Sichuan. J. Sichuan For. Sci. Technol. 2018, 39, 1–6, (In Chinese with English Abstract). [Google Scholar]
  11. Zhang, W.; Yang, K.; Lyu, Z.; Zhu, J. Microbial groups and their functions control the decomposition of coniferous litter: A comparison with broadleaved tree litters. Soil Biol. Biochem. 2019, 133, 196–207. [Google Scholar] [CrossRef]
  12. Sayer, E.J.; Tanner, E.V.J. Experimental investigation of the importance of litterfall in lowland semi-evergreen tropical forest nutrient cycling. J. Ecol. 2010, 98, 1052–1062. [Google Scholar] [CrossRef]
  13. Neumann, M.; Ukonmaanaho, L.; Johnson, J.; Benham, S.; Vesterdal, L.; Novotný, R.; Hasenauer, H. Quantifying carbon and nutrient input from litterfall in European forests using field observations and modeling. Glob. Biogeochem. Cycles 2018, 32, 784–798. [Google Scholar]
  14. Berg, B.; McClauhgerty, C.A. Plant Litter: Decomposition, Humus Formation, Carbon Sequestration, 3rd ed.; Springer: New York, NY, USA, 2014. [Google Scholar]
  15. Paudel, E.; Dossa, G.G.; Xu, J.; Harrison, R.D. Litterfall and nutrient return along a disturbance gradient in a tropical montane forest. For. Ecol. Manag. 2015, 353, 97–106. [Google Scholar]
  16. Zhang, H.; Yuan, W.; Dong, W.; Liu, S. Seasonal patterns of litterfall in forest ecosystem worldwide. Ecol. Complex. 2014, 20, 240–247. [Google Scholar]
  17. Tang, J.; Cao, M.; Zhang, J.; Li, M. Litterfall production, decomposition and nutrient use efficiency varies with tropical forest types in Xishuangbanna, SW China: A 10-year study. Plant Soil 2010, 335, 271–288. [Google Scholar]
  18. Acenolaza, P.G.; Zamboni, L.P.; Rodriguez, E.E.; Gallardo, J.F. Litterfall production in forests located at the Pre-delta area of the Parana River (Argentina). Ann. For. Sci. 2010, 67, 311. [Google Scholar] [CrossRef] [Green Version]
  19. Zhu, X.; Liu, W.; Chen, H.; Deng, Y.; Chen, C.; Zeng, H. Effects of forest transition on litterfall, standing litter and related nutrient returns: Implications for forest management in tropical China. Geoderma 2019, 333, 123–134. [Google Scholar] [CrossRef]
  20. Ni, X.; Lin, C.; Chen, G.; Xie, J.; Yang, Z.; Liu, X.; Yang, Y. Decline in nutrient inputs from litterfall following forest plantation in subtropical China. For. Ecol. Manag. 2021, 496, 119445. [Google Scholar]
  21. Lin, N.; Bartsch, N.; Heinrichs, S.; Vor, T. Long-term effects of canopy opening and liming on leaf litter production, and on leaf litter and fineroot decomposition in a European beech (Fagus sylvatica L.) forest. For. Ecol. Manag. 2015, 338, 183–190. [Google Scholar] [CrossRef]
  22. Wu, W.; Zhou, X.; Wen, Y.; Zhu, H.; You, Y.; Qin, Z.; Li, Y.; Huang, X.; Yan, L.; Li, H. Coniferous-broadleaf mixture increases soil microbial biomass and functions accompanied by improved stand biomass and litter production in subtropical China. Forests 2019, 10, 879. [Google Scholar]
  23. Vigulu, V.; Blumfield, T.J.; Reverchon, F.; Bai, S.; Xu, Z. Nitrogen and carbon cycling associated with litterfall production in monoculture teak and mixed species teak and flueggea stands. J. Soil Sediments 2019, 19, 1672–1684. [Google Scholar] [CrossRef]
  24. Tongkaemkaew, U.; Sukkul, J.; Sumkhan, N.; Panklang, P.; Brauman, A.; Ismail, R. Litterfall, litter decomposition, soil macrofauna, and nutrient contents in rubber monoculture and rubber-based agroforestry plantations. For. Soc. 2018, 2, 138–149. [Google Scholar] [CrossRef]
  25. Jimenez, M.N.; Navarro, F.B. Thinning effects on litterfall remaining after 8 years and improved stand resilience in Aleppo pine afforestation (SE Spain). J. Environ. Manag. 2016, 169, 174–183. [Google Scholar] [CrossRef] [PubMed]
  26. Blanco, J.A.; Imbert, J.B.; Castillo, F.J. Influence of site characteristics and thinning intensity on litterfall production in two Pinus sylvestris L. forests in the western Pyrenees. For. Ecol. Manag. 2006, 237, 342–352. [Google Scholar] [CrossRef]
  27. Ma, Y.; Cheng, D.; Zhong, Q.; Jin, B.; Xu, C.; Hu, B. Anisotropic ratio of different fractions of Chinese forest apoplankton. Chin. J. Plant Ecol. 2013, 37, 1071, (In Chinese with English Abstract). [Google Scholar] [CrossRef]
  28. Fu, C.; Yang, W.; Tan, B.; Xu, Z.; Zhang, Y.; Yang, J.; Wu, F. Seasonal dynamics of litterfall in a sub-alpine spruce-fir forest on the eastern Tibetan Plateau: Allometric scaling relationships based on one year of observations. Forests 2017, 8, 314. [Google Scholar] [CrossRef]
  29. Clark, D.A.; Brown, S.; Kicklighter, D.W.; Chambers, J.Q.; Thomlinson, J.R.; Ni, J. Measuring net primary production in forests: Concepts and field methods. Ecol. Appl. 2001, 11, 356–370. [Google Scholar] [CrossRef]
  30. Han, D.; Zhang, L.; Feng, M.; Wu, T.; Tie, L.; Li, W.; Wang, Y. Effects of transformation of Cypress funebrisf forest on soil microorganism, enzymatic activity and nutrient. J. Northeast For. Univ. 2016, 44, 57–62, (In Chinese with English Abstract). [Google Scholar]
  31. Wang, Y.; Chen, S.; He, W.; Ren, J.; Wen, X.; Wang, Y.; Fan, C. Shrub diversity and niche characteristics in the initial stage of reconstruction of low-efficiency Cupressus funebris stands. Forests 2021, 12, 1492. [Google Scholar] [CrossRef]
  32. Chen, J.; Niu, M.; Gong, G.; Zhou, D.; Zhu, Z.; Li, Y.; Zhen, S.; Xie, T.; Mu, C. Transformation of cypress monoculture by cutting in band and replanting in Sichuan central basin. Southwest China J. Agric. Sci. 2019, 32, 636–644, (In Chinese with English Abstract). [Google Scholar]
  33. Gong, G.; Niu, M.; Mu, C.; Chen, J.; Li, Y.; Zhu, Z.; Zhen, S. Impacts of different thinning intensities on growth of Cupressus funebris plantation and understory plants. Sci. Silvae Sin. 2015, 51, 8–15, (In Chinese with English Abstract). [Google Scholar]
  34. Li, Y.; Gong, G.; Zheng, S.; Chen, J.; Mu, C.; Zhu, Z.; Niu, M. Impact on water and soil conservation of different bandwidths in low-efficiency cypress forest transformation. Acta Ecol. Sin. 2013, 33, 934–943, (In Chinese with English Abstract). [Google Scholar]
  35. Lai, J.; Zou, Y.; Zhang, J.; Peres-Neto, P. Generalizing hierarchical and variation partitioning in multiple regression and canonical analyses using the rdacca. hp R package. Methods Ecol. Evol. 2022, 13, 782–788. [Google Scholar] [CrossRef]
  36. Rich, P.M. Plant allometry: The scaling of form and process. Ecology 1995, 76, 2342–2343. [Google Scholar] [CrossRef]
  37. Warton, D.I.; Weber, N.C. Common slope tests for bivariate errors-in-variables models. Biom. J. 2002, 44, 161–174. [Google Scholar] [CrossRef]
  38. Zhou, J.; Lang, X.; Du, B.; Zhang, H.; Liu, H.; Zhang, Y.; Shang, L. Litterfall and nutrient return in moist evergreen broad-leaved primary forest and mixed subtropical secondary deciduous broad-leaved forest in China. Eur. J. For. Res. 2016, 135, 77–86. [Google Scholar] [CrossRef]
  39. Bahru, T.; Ding, Y. Effect of stand density, canopy leaf area index and growth variables on Dendrocalamus brandisii (Munro) Kurz litter production at Simao District of Yunnan Province, southwestern China. Glob. Ecol. Conserv. 2020, 23, e01051. [Google Scholar] [CrossRef]
  40. Dai, Y.; Gong, F.; Yang, X.; Chen, X.; Su, Y.; Liu, L.; Sun, Q. Litterfall seasonality and adaptive strategies of tropical and subtropical evergreen forests in China. J. Plant Ecol. 2022, 15, 320–334. [Google Scholar] [CrossRef]
  41. Bray, J.R.; Gorham, E. Litter production in forests of the world. Adv. Ecol. Res. 1964, 2, 101–157. [Google Scholar]
  42. Roig, S.; del Río, M.; Cañellas, I.; Montero, S. Litter fall in Mediterranean Pinus pinaster Ait. stands under different thinning regimes. For. Ecol. Manag. 2005, 206, 179–190. [Google Scholar]
  43. Espinosa, J.; Madrigal, J.; Pando, V.; de la Cruz, A.C.; Guijarro, M.; Hernando, C. The effect of low-intensity prescribed burns in two seasons on litterfall biomass and nutrient content. Int. J. Wildland Fire 2020, 29, 1029–1041. [Google Scholar]
  44. Souza, S.R.; Veloso, M.D.; Espírito-Santo, M.M.; Silva, J.O.; Sánchez-Azofeifa, A.; Souza e Brito, B.G.; Fernandes, G.W. Litterfall dynamics along a successional gradient in a Brazilian tropical dry forest. For. Ecosyst. 2019, 6, 35. [Google Scholar]
  45. Morffi-Mestre, H.; Ángeles-Pérez, G.; Powers, J.S.; Andrade, J.L.; Huechacona Ruiz, A.H.; May-Pat, F.; Dupuy, J.M. Multiple factors influence seasonal and interannual litterfall production in a tropical dry forest in Mexico. Forests 2020, 11, 1241. [Google Scholar]
  46. Sun, X.; Liu, F.; Zhang, Q.; Li, Y.; Zhang, L.; Wang, J.; Wang, X. Biotic and climatic controls on the interannual variation in canopy litterfall of a deciduous broad-leaved forest. Agric. For. Meteorol. 2021, 307, 108483. [Google Scholar] [CrossRef]
  47. Liu, W.; Fox, J.E.; Xu, Z. Litterfall and nutrient dynamics in a montane moist evergreen broad-leaved forest in Ailao Mountains, SW China. Plant Ecol. 2003, 164, 157–170, (In Chinese with English Abstract). [Google Scholar] [CrossRef]
  48. Sun, J.; Niu, S.; Wang, J. Divergent biomass partitioning to aboveground and belowground across forests in China. J. Plant Ecol. 2018, 11, 484–492. [Google Scholar]
  49. Reich, P.B.; Wright, I.J.; Cavender-Bares, J.; Craine, J.M.; Oleksyn, J.; Westoby, M.; Walters, M.B. The evolution of plant functional variation: Traits, spectra, and strategies. Int. J. Plant Sci. 2003, 164, 143–164. [Google Scholar]
  50. Price, C.A.; Weitz, J.S.; Savage, V.M.; Stegen, J.; Clarke, A.; Coomes, D.A.; Dodds, P.S.; Etienne, R.S.; Kerkhoff, A.J.; McCulloh, K.; et al. Testing the metabolic theory of ecology. Ecology 2012, 15, 1465–1474. [Google Scholar]
  51. Niu, K.; Choler, P.; Zhao, B.; Du, G. The allometry of reproductive biomass in response to land use in Tibetan alpine grasslands. Funct. Ecol. 2009, 23, 274–283. [Google Scholar] [CrossRef]
Forests 13 01581 g001 550
Figure 1. Annual production of total litterfall (a) and its components ((b) leaf litter; (c) twig litter; (d) reproductive organ litter; (e) miscellaneous litter) in different plantations. PC: pure cypress; SF: strip filling; ET: ecological thinning. Different letters denote significant differences in values at the p < 0.05 level.
Figure 1. Annual production of total litterfall (a) and its components ((b) leaf litter; (c) twig litter; (d) reproductive organ litter; (e) miscellaneous litter) in different plantations. PC: pure cypress; SF: strip filling; ET: ecological thinning. Different letters denote significant differences in values at the p < 0.05 level.
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Forests 13 01581 g002 550
Figure 2. The proportions of each litter component in the total litterfall in different plantations. (a) PC: pure cypress; (b) SF: strip filling; (c) ET: ecological thinning.
Figure 2. The proportions of each litter component in the total litterfall in different plantations. (a) PC: pure cypress; (b) SF: strip filling; (c) ET: ecological thinning.
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Forests 13 01581 g003 550
Figure 3. Monthly production of total litterfall (a) and its components ((b) leaf litter; (c) twig litter; (d) reproductive organ litter; (e) miscellaneous litter) in different plantations. PC: pure cypress; SF: strip filling; ET: ecological thinning. Asterisks denote significant differences among the three plantations within the same month: * indicates p < 0.05; ** indicates p < 0.01; and *** indicates p < 0.001.
Figure 3. Monthly production of total litterfall (a) and its components ((b) leaf litter; (c) twig litter; (d) reproductive organ litter; (e) miscellaneous litter) in different plantations. PC: pure cypress; SF: strip filling; ET: ecological thinning. Asterisks denote significant differences among the three plantations within the same month: * indicates p < 0.05; ** indicates p < 0.01; and *** indicates p < 0.001.
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Forests 13 01581 g004 550
Figure 4. Seasonal production of total litterfall (a) and its components ((b) leaf litter; (c) twig litter; (d) reproductive organ litter; (e) miscellaneous litter) in different plantations. PC: pure cypress; SF: strip filling; ET: ecological thinning. Capital letters indicate differences among seasons within the same plantation, while lowercase letters indicate differences among the three plantations within the same seasons at the p < 0.05 level.
Figure 4. Seasonal production of total litterfall (a) and its components ((b) leaf litter; (c) twig litter; (d) reproductive organ litter; (e) miscellaneous litter) in different plantations. PC: pure cypress; SF: strip filling; ET: ecological thinning. Capital letters indicate differences among seasons within the same plantation, while lowercase letters indicate differences among the three plantations within the same seasons at the p < 0.05 level.
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Forests 13 01581 g005 550
Figure 5. Allometric relationships between each litter component and total litterfall (a–c) and among litter components (d–f) in different plantations. PC: pure cypress; SF: strip filling; ET: ecological thinning.
Figure 5. Allometric relationships between each litter component and total litterfall (a–c) and among litter components (d–f) in different plantations. PC: pure cypress; SF: strip filling; ET: ecological thinning.
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Figure 6. Relationships of vegetation factors with annual litterfall production (a) and of climate factors with monthly litterfall production (b) based on redundancy analysis (RDA). The data used in this analysis were the litterfall from the three plantations.
Figure 6. Relationships of vegetation factors with annual litterfall production (a) and of climate factors with monthly litterfall production (b) based on redundancy analysis (RDA). The data used in this analysis were the litterfall from the three plantations.
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Table
Table 1. Allometric scaling relationships between different litter components in different plantations (LTo: total litterfall; LL: leaf litterfall; LT: twig litterfall; LR: reproductive organ litterfall).
Table 1. Allometric scaling relationships between different litter components in different plantations (LTo: total litterfall; LL: leaf litterfall; LT: twig litterfall; LR: reproductive organ litterfall).
Parameter
(y-x)		PatternnScaling ExponentTest of Isometry
R2Slope95%CIF ValueType
LTo-LLPC300.936 ***1.080 a0.980~1.1912.633I
SF300.978 ***1.020 a0.963~1.0810.496I
ET300.962 ***0.984 a0.912~1.0620.184I
LTo-LTPC300.498 ***0.314 b0.240~0.412114.872 ***A
SF300.546 ***0.343 b0.265~0.444101.876 ***A
ET300.527 ***0.539 a0.414~0.70125.694 ***A
LTo-LRPC300.23 **0.237 b0.170~0.331143.960 ***A
SF300.316 **0.547 a0.399~0.7516.799 ***A
ET300.435 ***0.443 a0.333~0.59140.725 ***A
LL-LTPC300.431 ***0.291 b0.218~0.388121.981 ***A
SF300.444 ***0.336 b0.253~0.44787.453 ***A
ET300.362 ***0.547 a0.404~0.74217.958 ***A
LL-LRPC300.0680.220 0.152~0.316//
SF300.229 **0.536 a0.384~0.74916.017 ***A
ET300.321 ***0.450 a0.329~0.61632.312 ***A
LT-LRPC300.0780.755 0.525~1.086//
SF300.159 *1.594 a1.126~2.2577.780 **A
ET300.332 ***0.823 b0.603~1.1231.620I
Notes: PC: pure cypress; SF: strip filling; ET: ecological thinning. A indicates an allometric growth relationship, and I indicates an isometric growth relationship. Different lowercase letters indicate significant differences between the plantations (p < 0.05). * indicates p < 0.05; ** indicates p < 0.01; and *** indicates p < 0.001.
Table
Table 2. The relative influences (RI%) of vegetation factors on annual litterfall and of climate factors on monthly litterfall and their p values based on redundancy analysis and hierarchical partitioning analysis.
Table 2. The relative influences (RI%) of vegetation factors on annual litterfall and of climate factors on monthly litterfall and their p values based on redundancy analysis and hierarchical partitioning analysis.
FactorsRI (%)p Value
Annual litterfall
Stand density9.660.104
Canopy density7.110.130
Species richness11.640.063
Tree height16.140.026
Diameter at breast height17.850.024
Monthly litterfall
Mean wind speed9.090.001
Precipitation5.410.001
Air temperature16.380.001
Relative humidity15.950.001
Bold p values are significant (p < 0.05).
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Yang, Y.; Yang, H.; Wang, Q.; Dong, Q.; Yang, J.; Wu, L.; You, C.; Hu, J.; Wu, Q. Effects of Two Management Practices on Monthly Litterfall in a Cypress Plantation. Forests 2022, 13, 1581. https://doi.org/10.3390/f13101581

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Yang Y, Yang H, Wang Q, Dong Q, Yang J, Wu L, You C, Hu J, Wu Q. Effects of Two Management Practices on Monthly Litterfall in a Cypress Plantation. Forests. 2022; 13(10):1581. https://doi.org/10.3390/f13101581

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Yang, Yulian, Honglin Yang, Qiang Wang, Qing Dong, Jiaping Yang, Lijun Wu, Chengming You, Jinyao Hu, and Qinggui Wu. 2022. "Effects of Two Management Practices on Monthly Litterfall in a Cypress Plantation" Forests 13, no. 10: 1581. https://doi.org/10.3390/f13101581

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